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Chinese textile and garment exports rebounded in March
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《China Textile》 2023年第2期56-56,共1页
According to data released by the General Ad­ministration of Customs on April 13th,China's textile and garment exports stopped falling and rebounded in March,which was more than that in February this year and... According to data released by the General Ad­ministration of Customs on April 13th,China's textile and garment exports stopped falling and rebounded in March,which was more than that in February this year and the same period last year,and the overall export stabilized. 展开更多
关键词 GARMENT stopped REBOUND
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Th e main economic indicators of the chemical fi ber industry rebounded
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作者 Zhong Mengxia 《China Textile》 2022年第4期39-41,共3页
In the first half of the year,unexpected factors,such as the rebound of domestic pandemic and international geopolitical conflicts,have impacted China’s economic operation,and the risks and challenges faced by its de... In the first half of the year,unexpected factors,such as the rebound of domestic pandemic and international geopolitical conflicts,have impacted China’s economic operation,and the risks and challenges faced by its development are constant.In this context,the crude oil price fluctuates greatly,the downstream demand continues to be low,and the overall production and operation situation of chemical fiber industry is grim.However,under the support of a series of"steady growth"policies and measures of the state,the main operational indicators of the textile industry have been under pressure and rebounded.It is expected that in the second half of the year,with the further implementation of policies and measures,it will bring more positive impacts on the smooth operation and recovery of the industry. 展开更多
关键词 measures REBOUND INDUSTRY
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Changes of spring wind erosion based on wind erosion climate factor in the black soil region of Northeast China
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作者 YAN Ping JI Sheng-tai +5 位作者 LI Xiu-fen ZHU Hai-xia WANG Liang-liang ZHAI Mo WANG Ping ZHAO Hui-ying 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1712-1724,共13页
The dry and windy climate and low ground cover in spring in the black soil region of Northeast China make the soil strongly affected by wind erosion,which seriously threatens the food security and ecological security ... The dry and windy climate and low ground cover in spring in the black soil region of Northeast China make the soil strongly affected by wind erosion,which seriously threatens the food security and ecological security of this region.In this paper,based on the daily observation data of 124 meteorological stations in study area from 1961 to 2020,seasonal and monthly wind erosion climate factor(C)in spring(March to May)were calculated by using the method proposed by the Food and Agriculture Organization of the United Nations(FAO),the wind erosion characterization in spring were systematically analyzed based on C by various statistical analysis methods.The results showed that in the past 60 years,spring wind erosion climate factor(CSp)and monthly C of the whole region and each province(region)all showed highly significant decreasing trend,but they began to show rebounded trend in the middle or late 2000s.CSp of the study area showed a significant upward trend since 2008 with an increase of 4.59(10a)^(-1).The main contributors to this upward trend are the changes of C in March and in April.For the four provinces(regions),CSp in Heilongjiang,Jilin,Liaoning and eastern Inner Mongolia all showed rebounded since 2008,2011,2008 and 2009,respectively.The rebounded trend of CSp in eastern Inner Mongolia was the most obvious with a tendency rate of 11.27(10a)^(-1),and its mutation occurred after 1984.The rebound trend of CSp in Heilongjiang Province takes the second place,with a trend rate of 4.72(10a)^(-1),but there’s no obvious time mutation characteristics.The spatial characteristics of CSpand monthly C are similar,showing decreasing characteristics centered on the typical black soil belt of Northeast China.Compared with 1961-1990,in the period from 1991 to 2020,the proportion of high value areas(CSp>35,monthly C>10)has decreased to varying degrees,while the proportion of low value areas(CSp≤10,monthly C≤4)has increased.The trends of seasonal and monthly C in 82.2%~87.7%of the stations show significant decreases at 95%confidence level.CSp is closely related to wind speed at 2m height,temperature difference,minimum temperature and precipitation in the same period,of which the correlation between CSp and wind speed is the strongest,indicating that the main control factor for CSp in the study area is wind speed,but the impact of the change of temperature and precipitation on CSp cannot be ignored. 展开更多
关键词 Wind erosion climate erosivity Spatiotemporal 1characteristics Climate change rebounded trend Typical black soil region Northeast China
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July Trade Surplus Rebounded
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作者 Lily Wang 《China Chemical Reporter》 2008年第24期7-7,共4页
On August 11th,2008 the General Adminis-tration of Customs of China announced China’s foreign trade in July 2008.The to talimport and export value was US$248.
关键词 CUSTOMS BILATERAL TEXTILES thousand REBOUND materi
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Bifurcations for counterintuitive post-inhibitory rebound spike related to absence epilepsy and Parkinson disease
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作者 王宪军 古华光 +2 位作者 贾雁兵 陆博 周辉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期206-219,共14页
Seizures are caused by increased neuronal firing activity resulting from reduced inhibitory effect and enhancement of inhibitory modulation to suppress this activity is used as a therapeutic tool.However,recent experi... Seizures are caused by increased neuronal firing activity resulting from reduced inhibitory effect and enhancement of inhibitory modulation to suppress this activity is used as a therapeutic tool.However,recent experiments have shown a counterintuitive phenomenon that inhibitory modulation does not suppress but elicit post-inhibitory rebound(PIR)spike along with seizure to challenge the therapeutic tool.The nonlinear mechanism to avoid the PIR spike can present theoretical guidance to seizure treatment.This paper focuses on identifying credible bifurcations that underlie PIR spike by modulating multiple parameters in multiple theoretical models.The study identifies a codimension-2 bifurcation called saddle-node homoclinic orbit(SNHOB),which is an intersection between saddle node bifurcation on invariant cycle(SNIC)and other two bifurcations.PIR spike cannot be evoked for the SNIC far from the SNHOBbut induced for the SNIC close to the SNHOB,which extends the bifurcation condition for PIR spike from the well-known Hopf to SNIC.Especially,in a thalamic neuron model,increases of conductance of T-type Ca^(2+)(TC a)channel induce SNIC bifurcation approaching to the SNHOB to elicit PIR spikes,closely matching experimental results of the absence seizure or Parkinson diseases.Such results imply that,when inhibition is employed to relieve absence seizure and Parkinson diseases related to PIR spike,modulating SNIC to get far from the SNHOBto avoid PIR spike is the principle.The study also addresses the complex roles of TCacurrent and comprehensive relationships between PIR spike and nonlinear conceptions such as bifurcation types and shapes of threshold curve. 展开更多
关键词 bifurcation threshold post-inhibitory rebound spike brain disease
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Vertical deformation before and after the 2022 Menyuan Ms6.9 earthquake and analysis of earthquake precursors
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作者 Sixin Zhang Peng Jia +1 位作者 Bowen Hou Ming Hao 《Geodesy and Geodynamics》 EI CSCD 2023年第6期582-588,共7页
This study analyzed the vertical deformation before and after the 2022 Menyuan Ms6.9 earthquake in Qinghai Province,China,using leveling profiles across faults measured from Minle County in Gansu Province to Menyuan C... This study analyzed the vertical deformation before and after the 2022 Menyuan Ms6.9 earthquake in Qinghai Province,China,using leveling profiles across faults measured from Minle County in Gansu Province to Menyuan County in Qinghai Province.Our results suggest the following:(1)The amplitude of regional vertical differential motion near the Sunna-Qilian and Lenglongling faults within the Qilian Shan increased before the 2022 Menyuan earthquake.It was accompanied by the emergence of high gradient deformation zones.Deformation at the Tongziba cross-fault leveling site near the Sunan-Qilian fault was considerable.In contrast,deformation at the Daliang cross-fault leveling site near the stepover region(adjacent to the epicenter)between the Lenglongling and Tuolaishan faults was minor.After 2018,vertical deformation at the Tongziba site notably accelerated,while that at the Daliang site was insignificant.(2)After the 2022 Menyuan earthquake,140—150 mm of subsidence deformation occurred near the Daliang site,while the Tongziba site did not experience significant deformation.(3)Vertical deformation before and after the 2022 Menyuan earthquake conforms with the elastic-rebound theory,and the evolution of pre-earthquake deformation was consistent with the strike-slip fault deformation pattern at different seismogenic stages,i.e.,the relative motion near the locked fault in the late seismogenic stage gradually weakened.The characteristics of strain accumulation and release derived from the vertical deformation before and after the Menyuan MS6.9 earthquake help understand the deformation process of earthquake preparation and earthquake precursors. 展开更多
关键词 2022 Menyuan earthquake 2016 Menyuan earthquake LEVELING Vertical deformation Elastic rebound
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Eff ect of post-rewarming fever after targeted temperature management in cardiac arrest patients: a systematic review and meta-analysis
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作者 Guang-qi Guo Yan-nan Ma +2 位作者 Shuang Xu Hong-rong Zhang Peng Sun 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第3期217-223,共7页
BACKGROUND:Targeted temperature management(TTM),as a therapeutic temperature control strategy for cardiac arrest(CA),is recommended by guidelines.However,the relationship between postrewarming fever(PRF)and the progno... BACKGROUND:Targeted temperature management(TTM),as a therapeutic temperature control strategy for cardiac arrest(CA),is recommended by guidelines.However,the relationship between postrewarming fever(PRF)and the prognosis of CA patients is unclear.Therefore,we aim to summarize the studies regarding the infl uence of PRF on patients with CA.METHODS:EMBASE,PubMed,and Cochrane Central databases were searched from inception to March 13,2022.Randomized clinical trials(RCTs)and cohort studies on PRF in CA patients were included.According to the heterogeneity,the meta-analysis was performed using a random eff ects model or fi xed eff ects model to calculate the pooled odds ratios(ORs)and corresponding 95%confi dence intervals(CIs).The outcome data were unfavorable neurological outcome and mortality.RESULTS:The meta-analysis included 11 observational studies involving 3,246 patients.The results of the meta-analysis show that PRF(body temperature>38.0℃)has no eff ect on the neurological outcome of CA patients(OR 0.71,95%CI 0.43–1.17,I282%)and has a signifi cant relationship with lower mortality(OR 0.63;95%CI 0.49–0.80,I239%).However,PRF with a stricter defi nition(body temperature>38.5℃)was associated with worse neurological outcome(OR 1.44,95%CI 1.08–1.92,I245%)and higher mortality(OR 1.71,95%CI 1.25–2.35,I247%).CONCLUSION:This study suggests that PRF>38.0℃ may not affect the neurological outcome and have a lower mortality in CA patients who completed TTM.However,PRF>38.5℃ is a potential prognostic factor for worse outcomes in CA patients. 展开更多
关键词 Cardiac arrest Target temperature management Post-rewarming fever Rebound hyperthermia
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Compressive Strength of Basic Magnesium Sulfate Cement Coral Aggregate Concrete(MCAC)on Non-Destructive Testing
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作者 GUO Jianbo YU Hongfa +3 位作者 MA Haiyan CHANG Yun MEI Qiquan ZHANG Yan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1086-1095,共10页
Basic magnesium sulfate cement coral aggregate concrete(MCAC)is a new type of concrete consisting of basic magnesium sulfate cement,coarse coral aggregate,coral reef sand and seawater.The rebound hammer(RH),the ultras... Basic magnesium sulfate cement coral aggregate concrete(MCAC)is a new type of concrete consisting of basic magnesium sulfate cement,coarse coral aggregate,coral reef sand and seawater.The rebound hammer(RH),the ultrasonic pulse velocity(UPV)and the compressive strength(fcu)tests of 14 sets of cube specimens of the MCAC after 28 d of aging were conducted.The impact of the content and length of sisal fiber on the relationship between the fcu-RH and the fcu-UPV was determined.A mathematical model was established to predict the strength of the MCAC using the UPV,RH,and comprehensive UPV/RH methods and to obtain the curves of test strength.The applicability of the test strength curves of ordinary portland concrete(OPC),light-weight aggregate concrete(LAC),and coral aggregate concrete(CAC)to MCAC was assessed.The results showed that the test strength curves of OPC,LAC and CAC were inappropriate to determine the strength of MCAC using non-destructive method.The relative standard error of the curves of test strength of the RH method and the comprehensive method met the specifications,whereas that of the UPV method did not. 展开更多
关键词 non-destructive testing basic magnesium sulfate cement coral aggregate corcrete ultrasonic pulse velocity rebound hammer specific test strength curves
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Level set method for numerical simulation of a cavitation bubble,its growth, collapse and rebound near a rigid wall 被引量:6
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作者 Juntao Huang Huisheng Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第6期645-653,共9页
A level set method of non-uniform grids is used to simulate the whole evolution of a cavitation bubble, including its growth, collapse and rebound near a rigid wall. Single-phase Navier-Stokes equation in the liquid r... A level set method of non-uniform grids is used to simulate the whole evolution of a cavitation bubble, including its growth, collapse and rebound near a rigid wall. Single-phase Navier-Stokes equation in the liquid region is solved by MAC projection algorithm combined with second-order ENO scheme for the advection terms. The moving inter-face is captured by the level set function, and the interface velocity is resolved by "one-side" velocity extension from the liquid region to the bubble region, complementing the second-order weighted least squares method across the interface and projection inside bubble. The use of non-uniform grid overcomes the difficulty caused by the large computational domain and very small bubble size. The computation is very stable without suffering from large flow-field gradients, and the results are in good agreements with other studies. The bubble interface kinematics, dynamics and its effect on the wall are highlighted, which shows that the code can effectively capture the "shock wave"-like pressure and velocity at jet impact, toroidal bubble, and complicated pressure structure with peak, plateau and valley in the later stage of bubble oscillating. 展开更多
关键词 Level set method Cavitation bubble Collapsing and rebounding Jet impact Toroidal bubble
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Influence of tectonic uplift-erosion on formation pressure 被引量:5
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作者 Xu Hao Zhang Junfeng +2 位作者 Jia Chengzao Tang Dazhen Yin Wei 《Petroleum Science》 SCIE CAS CSCD 2010年第4期477-484,共8页
The formation of abnormally low-pressure hydrocarbon reservoirs in petroliferous basins has a close relationship with tectonic uplift and the consequent erosion. In order to understand abnormally low-pressure reservoi... The formation of abnormally low-pressure hydrocarbon reservoirs in petroliferous basins has a close relationship with tectonic uplift and the consequent erosion. In order to understand abnormally low-pressure reservoirs and to provide a scientific basis for exploration and development, we established, through numerical simulation and theoretical analysis, a set of equations for the formation pressure in a closed system influenced by uplift-erosion, discussed the relationship between the genesis of abnormal pressure and uplift-erosion, and put forward the concept of balance pressure (P b ). The results showed that abnormally high pressure coefficient may form when the current formation pressure was higher than P b , and abnormally low pressure may form when the current formation pressure was lower than P b . In the Santanghu Basin, the current formation pressure of abnormally low pressure reservoirs is lower than P b , so tectonic uplift-erosion leads to the decrease of the pressure coefficient. There is a positive correlation between the pressure drop caused by the decrease of fluid temperature and the rebound of rock porosity and strata erosion. Calculation results indicated that the reservoir pressure of Jurassic strata in the Santanghu Basin was decreased by 11.6-17.1 MPa due to tectonic uplift-erosion during the Late Yanshanian period. 展开更多
关键词 Uplift-erosion formation pressure temperature decrease porosity rebound abnormally low pressure Santanghu Basin
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Impact of corneal parameters on intraocular pressure measurements in different tonometry methods 被引量:6
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作者 Aleksandra Zakrzewska Marta P.Wi?cek Anna Machalińska 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第12期1853-1858,共6页
AIM: To evaluate the impact of central corneal thickness(CCT) and corneal curvature on intraocular pressure(IOP) measurements performed by three different tonometers. METHODS: IOP in 132 healthy eyes of 66 participant... AIM: To evaluate the impact of central corneal thickness(CCT) and corneal curvature on intraocular pressure(IOP) measurements performed by three different tonometers. METHODS: IOP in 132 healthy eyes of 66 participants was measured using three different tonometry techniques: Goldmann applanation tonometer(GAT), Pascal dynamic contour tonometer(DCT), and ICare rebound tonometer(RT). CCT and corneal curvature were assessed. RESULTS: In healthy eyes, DCT presents significantly higher values of IOP than GAT(17.34±3.69 and 15.27±4.06 mm Hg, P<0.0001). RT measurements are significantly lower than GAT(13.56±4.33 mm Hg, P<0.0001). Compared with GAT, DCT presented on average 2.51 mm Hg higher values in eyes with CCT<600 μm and 0.99 mm Hg higher results in eyes with CCT≥600 μm. The RT results were lower on average by 1.61 and 1.95 mm Hg than those obtained by GAT, respectively. Positive correlations between CCT in eyes with CCT<600 μm were detected for all IOP measurement techniques, whereas a similar relationship was not observed in eyes with thicker corneas. A correlation between IOP values and keratometry in the group with CCT<600 μm was not detected with any of the tonometry methods. In thicker corneas, a positive correlation was found for GAT and mean keratometry values(R=0.369, P=0.005). CONCLUSION: The same method should always be chosen for routine IOP control, and measurements obtained by different methods cannot be compared. All analysed tonometry methods are dependent on CCT;thus, CCT should be taken into consideration for both diagnostics and monitoring. 展开更多
关键词 intraocular pressure Goldmann applanation tonometer Pascal dynamic contour tonometer ICare rebound tonometer central corneal thickness corneal curvature healthy individuals
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The Testing Strength Curves of Lightweight Aggregate Concrete by Rebound Method and Ultrasonic-rebound Combined Method 被引量:3
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作者 荣辉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第5期1010-1017,共8页
The strength curves of lightweight aggregate concrete (LWAC) were tested based on detecting LWAC with density of 1 400-1 900 kg/m3 and LWAC with strength grade of LC15-LC50 by rebound method and ultrasonic-rebound c... The strength curves of lightweight aggregate concrete (LWAC) were tested based on detecting LWAC with density of 1 400-1 900 kg/m3 and LWAC with strength grade of LC15-LC50 by rebound method and ultrasonic-rebound combined method.The results show that the common measured strength curves tested by above two methods can not satisfy the required accuracy of LWAC strength test.In addition,specified compressive strength curves of testing LWAC by rebound method and ultrasonic-rebound combined method are obtained,respectively. 展开更多
关键词 lightweight aggregate concrete compressive strength rebound method testing-strength curve ultrasonic-rebound combined method
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Characterization of Surface Hardness and Microstructure of High Performance Concrete 被引量:3
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作者 杨永敢 张云升 SHE Wei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第1期124-132,共9页
The relationship between compressive strength obtained by universal testing machine and rebound value obtained by the hammer of high performance concrete was systematically investigated at the macro level. And a model... The relationship between compressive strength obtained by universal testing machine and rebound value obtained by the hammer of high performance concrete was systematically investigated at the macro level. And a model of high performance concrete strength curve was established from them. At the micro level, the microstructure, hydration products and pore structure of concrete surface were analyzed by scanning electron microscopy(SEM), comprehensive thermal analysis(TG-DSC) and mercury intrusion porosimetry(MIP), respectively. The effect of carbonation on surface strength was also investigated. The results showed that the concrete surface hardness layer grew rapidly at early stage and then stabilized at last with ongoing curing age; the rebound value and compressive strength of concrete with slag were higher than those of concrete with the same content of fly ash. In addition, the strength curve obtained by the least square method can satisfy the local standard requirements with an average relative error of 8.9% and a relative standard deviation of 11.3%. When the carbonation depth was 6 mm, the compressive strength calculated by national uniform strength curve was 25 PMa higher than that by high performance concrete. 展开更多
关键词 high performance concrete rebound test parameter analysis strength curve
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Anisotropy effect on strengths of metamorphic rocks 被引量:2
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作者 Ahmet ?zbek Murat Gül +1 位作者 Ergun Karacan Ovünc Alca 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2018年第1期164-175,共12页
This paper aims to study the effect of anisotropy on strengths of several metamorphic rocks of southern(Cine) submassif of Menderes metamorphic massif in southwest Turkey. Four different metamorphic rocks including fo... This paper aims to study the effect of anisotropy on strengths of several metamorphic rocks of southern(Cine) submassif of Menderes metamorphic massif in southwest Turkey. Four different metamorphic rocks including foliated phyllite, schist, gneiss and marble(calcschist) were selected and examined.Discontinuity surveys were made along lines for each rock and evaluated with DIPS program. L-type Schmidt hammer was applied in the directions parallel and perpendicular to foliation during the field study. Several hand samples and rock blocks were collected during the field study for measurements of dry and saturated densities, dry and saturated unit weights and porosity, and for petrographic analysis and strength determination in laboratory. L-and N-type Schmidt hammers were applied in the directions perpendicular(anisotropy angle of 0°) and parallel(anisotropy angle of 90) to the foliation on selected blocks of phyllite, schist, gneiss and marble(calcschist). The phyllite and schist have higher porosity and lower density values than the other rocks. However, coarse crystalline gneiss and marble(calcschist) have higher rebound values and strengths, and they are classified as strong-very strong rocks. Generally, the rebound values in the direction perpendicular to the foliation are slightly higher than that in the direction parallel to foliation. Rebound values of N-type Schmidt hammer are higher than the L-type values except for phyllite. Sometimes, the rebound values of laboratory and field applications gave different results. This may result from variable local conditions such as minerals differentiation,discontinuities, water content, weathering degree and thickness of foliated structure. 展开更多
关键词 Rock anisotropy Field survey Schmidt hammer rebound values Southwest Turkey
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EFFECTS OF DESENSITIZATION AND REBOUND TO ADENOSINE ON ACTION POTENTIAL AND CONTRACTILITY IN ATRIAL CELLS IN GUINEA-PIGS 被引量:1
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作者 张凤杰 臧伟进 +4 位作者 于晓江 胡浩 张春虹 孙强 吕军 《Academic Journal of Xi'an Jiaotong University》 CAS 2002年第2期151-154,共4页
Objective To investigate the effects of desensitization and rebound to adenosine(Ado) on action potential duration(APD) and contractility in guinea-pig atrial cells. Methods Electrical activity was recorded using stan... Objective To investigate the effects of desensitization and rebound to adenosine(Ado) on action potential duration(APD) and contractility in guinea-pig atrial cells. Methods Electrical activity was recorded using standard intracellular microelectrode technique and contractility was recorded using. We studied the effects of adenosine on the action potential and desensitization of contractility and rebound of contractility. Results The results showed that action potential duration were shortened by 1,10, 100μ mol·L -1Ado, the ratio of shortened APD was ( 9.58± 1.40)%,(13.80±2.26)%,(24.80±3.19)%, respectively. 1 μ mol·L -1Ado had no desensitization ( P >0.05), but the time of desensitization of 10μ mol·L -1 Ado and 100μ mol·L -1 Ado was 1 minute( P <0.05) and 5 minutes( P < 0.05), respectively. The desensitization of contractility of 10?μ mol·L -1 Ado was obvious in atrial cells, the decrease of contractility of 10?μ mol·L -1 Ado was obvious in atrial cells, the decrease of contractility was changed from (31.4± 16.04)%(2 minutes) to (50.60±15.87)% (4 minutes), compared with control. After washing out Ado, contractility was shown to rebound, the ratio of increase of contractility by 1,10,100 μ mol·L -1 Ado was (12.38±7.50)%,(19.00± 8.14)% and (27.60±13.44)%, respectively. Conclusion Ado can abbreviate APD in atrial cells. The desensitization of Ado on APD is characterized by concentration-dependent and time-dependent in atrial cells, and the desensitization of contractility of Ado is obvious and contractility was shown to rebound after washing out Ado. 展开更多
关键词 ADENOSINE DESENSITIZATION REBOUND ATRIAL CELLS APD CONTRACTILITY
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Dynamics and rebound behavior analysis of flexible tethered satellite system in deployment and station-keeping phases 被引量:1
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作者 Yue Zhang Xin Jiang +2 位作者 Zheng-feng Bai Jia-wen Guo Cheng Wei 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第3期509-523,共15页
The tether deployment of a tethered satellite system involves the consideration of complex dynamic properties of the tether,such as large deformation,slack,and even rebound,and therefore,the dynamic modelling of the t... The tether deployment of a tethered satellite system involves the consideration of complex dynamic properties of the tether,such as large deformation,slack,and even rebound,and therefore,the dynamic modelling of the tether is necessary for performing a dynamic analysis of the system.For a variablelength tether element,the absolute nodal coordinate formulation(ANCF)in the framework of the arbitrary Lagrange-Euler(ALE)description was used to develop a precise dynamic model of a tethered satellite.The model considered the gravitational gradient force and Coriolis force in the orbital coordinate frame,and it was validated through numerical simulation.In the presence of dynamic constraints,a deployment velocity of the tether was obtained by an optimal procedure.In the simulation,rebound behavior of the tethered satellite system was observed when the ANCF-ALE model was employed.Notably,the rebound behavior cannot be predicted by the traditional dumbbell model.Furthermore,an improved optimal deployment velocity was developed.Simulation results indicated that the rebound phenomenon was eliminated,and smooth deployment as well as a stable state of the station-keeping process were achieved.Additionally,the swing amplitude in the station-keeping phase decreased when a deployment strategy based on the improved optimal deployment velocity was used. 展开更多
关键词 Tethered satellite system Dynamic model REBOUND DEPLOYMENT ANCF-ALE
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Extension Model of Crustal Uplifting in Western Shandong 被引量:1
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作者 Yan Shouxun, Institute of Remote Sensing Applications, Chinese Academy of Sciences, BeijingWang Guiliang, Shao Zhenjie, China University of Mining and Technology, Xuzhou, Jiangsuand Meng Xiangang Institute ofGeomechanics, Ministry of Geology and Mineral Resources of China, Beijing Fei Zhenbi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1996年第3期219-232,共14页
Block faults, as the -dominant tectonic framwork of western Shandong, were formed by the linked extensional fault system through two extensional movements during the Meso-Cenozoic. Both of the extensional movements ex... Block faults, as the -dominant tectonic framwork of western Shandong, were formed by the linked extensional fault system through two extensional movements during the Meso-Cenozoic. Both of the extensional movements experienced the same evloutional process: first, the upper crust was pulled apart to form faults; then the Tai-Lu-Yi (Taishan-Lushan-Yishan) fault block occurring in the footwall of the extensional fault was uplifted, which induced the shallow-level detachment movement along the early Precambrian and Palaeozoic unconformity; the ' branching' fault in the upper part of the deep-level detachment layer propagated. As the shallow detachment moved towards the north and the deep one towards the south, the Tai-Lu-Yi fault block acted as the common footwall of both the southern and northern detachment systems. The Tai-Lu-Yi fault block rebounded and uplifted as the overlying material was pulled apart to cause an unloading. Sialic material of the mid-crust below the deep detachment flowed to and accumulated in the free space below the rebounding uplifted body and thickened the body; whereas the mid-crust thinned under the graben systems. The rebounding uplifted body cooled, and then the graben system was occluded, which resulted in the crust-mantle isostatic adjustment and asthenospheric convection. As a result of the two extensional movements, the uplifted central Shandong block with the Tai-Lu-Yi area as the core stands highly above the surrounding plain characterized by graben systems. The present Mount Taishan forms the climax of the uplift. 展开更多
关键词 extensional linked system extensional cycle mantle-derived magma rebounding uplift crustal fluid layer crust-mantle isostatic adjustment.
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Rebound effect and its decomposition-an analysis based on energy types in China 被引量:1
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作者 Yu Liu Meifang Zhou +1 位作者 Shenghao Feng Yi Wang 《Chinese Journal of Population,Resources and Environment》 2016年第4期245-252,共8页
Rebound effect derived from energy efficiency improvement has been widely invested.However,most of studies focus on the rebound effect of the energy composite level and neither distinguish nor compare different energy... Rebound effect derived from energy efficiency improvement has been widely invested.However,most of studies focus on the rebound effect of the energy composite level and neither distinguish nor compare different energy types.We compare the differences in energy saving and energy rebound between primary and secondary energy sources,and further decompose the rebound effect into production rebound part and final demand component.To do so,we add a module for rebound into a comparative state China-CGE model.We design and test two simulation scenarios using the model.In Scenario 1,all production sectors' energy efficiency of using primary energy increases by 5%.In Scenario 2,all production sectors' energy efficiency of using secondary energy increases by 5%.The results show that Scenario 2 leads to more GDP growth and more energy saving.Our scenarios show rebound effects range between 9.6% and 27.9%,and in general are higher when energy efficiency of using primary energy sources is improved.Our decomposition analysis shows that improving energy efficiency in production sectors would stimulates energy use of final demand.Indeed,the consumption side has significant contribution to rebound in secondary energy use,especially in crude oil and gas.This study reveals that improving efficiency of using secondary energy is better than improving that of primary energy,both in terms of economic impact and energy rebound.And complementary policies that prevent energy services prices from falling too much can be adopted to reduce rebound.Controlling residential energy use could also be effective in reducing rebound,this has particular implication to economies in which residential energy consumption are far from saturation. 展开更多
关键词 Rebound effects energy efficiency energy type CGE model
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Intraocular pressure measurement over soft contact lens by rebound tonometer: a comparative study 被引量:1
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作者 Senay Asik Nacaroglu Emine Seker Un +1 位作者 Mehmet Giray Ersoz Yelda Tasci 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第3期540-543,共4页
AIM: To evaluate the intraocular pressure(IOP)measurements by Icare rebound tonometer over a contact lens in comparison with Goldmann applanation tonometry(GAT). METHODS: Fifty patients using contact lens were include... AIM: To evaluate the intraocular pressure(IOP)measurements by Icare rebound tonometer over a contact lens in comparison with Goldmann applanation tonometry(GAT). METHODS: Fifty patients using contact lens were included in this study. One of the eyes of the patients was selected randomly and their IOP were measured by rebound tonometer with and without contact lens(RTCL,RT respectively) and by GAT, as well as their central corneal thickness(CCT) by optical pachymeter. The results of both methods were compared by correlation analysis, general linear method repeated measure and Bland-Altman analysis.RESULTS: Mean IOP values measured by RTCL, RT and GAT were 15.68 ±3.7, 14.50 ±3.4 and 14.16 ±2.8(P 【0.001), respectively. Mean IOP by RTCL was significantly higher than the measurements implemented by RT and GAT(P 【0.001), while there was no difference between the measurements by GAT and RT(P =0.629). There was a good level of positive correlation between GAT and RTCL as well as RT(r =0.786 P 【0.001, r =0.833 P 【0.001, respectively). We have observed that CCT increase did not show any correlation with the differences of the measurements between RTCL and RT(P =0.329), RTCL and GAT(P =0.07) as well as RT and GAT(P =0.189) in linear regression model.CONCLUSION: The average of the measurements over contact lens by rebound tonometer was found to be higher than what was measured by GAT. Although this difference is statistically significant, it may be clinically negligible in the normal population. 展开更多
关键词 contact lens intraocular pressure rebound tonometer
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Study of Mechanical and Physical Properties of Palm Fiber Reinforced Acrylonitrile Butadiene Styrene Composite 被引量:2
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作者 Budrun Neher Md. Mahbubur Rahman Bhuiyan +3 位作者 Humayun Kabir Md. Rakibul Qadir Md. Abdul Gafur Farid Ahmed 《Materials Sciences and Applications》 2014年第1期39-45,共7页
Palm fiber (PF) reinforced acrylonitrile butadiene styrene (ABS) composite matrix was prepared by employing Injection Moulding Machine (IMM). Palm fiber was collected from ten different trees of different age group fr... Palm fiber (PF) reinforced acrylonitrile butadiene styrene (ABS) composite matrix was prepared by employing Injection Moulding Machine (IMM). Palm fiber was collected from ten different trees of different age group from Comilla region in Bangladesh. Three sets of samples were prepared for three different wt% (5%, 10% and 20%) of fiber contents. The mechanical (tensile strength, flexural stress, micro hardness, Leeb’s rebound hardness) and physical (bulk density and water absorption) properties were measured. The observed result reveals that the tensile strength (TS) and flexural stress (FS) were decreased with increasing fiber contents in the PF-ABS composites except 10% fiber content. 展开更多
关键词 Acrylonitrile BUTADIENE Styrene COMPOSITE Tensile STRESS Flexural STRESS Vicker’s HARDNESS and Leeb’s REBOUND HARDNESS
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