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Dense Shaped Refractory Products——Test Method of Linear Changes on Reheating
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《China's Refractories》 CAS 2006年第2期36-38,共3页
This Standard specifies methods for the determination of the linear changes on reheating of a dense shaped refractory product.
关键词 TEST Test method of Linear changes on Reheating Dense Shaped Refractory Products
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Set Programming Method and Performance Improvement of Phase Change Random Access Memory Arrays
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作者 范茜 陈后鹏 +6 位作者 王倩 王月青 吕士龙 刘燕 宋志棠 冯高明 刘波 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期184-187,共4页
A novel slow-down set waveform is proposed to improve the set performance and a 1 kb phase change random access memory chip fabricated with a 13nm CMOS technology is implemented to investigate the set performance by d... A novel slow-down set waveform is proposed to improve the set performance and a 1 kb phase change random access memory chip fabricated with a 13nm CMOS technology is implemented to investigate the set performance by different set programming strategies based on this new set pulse. The amplitude difference (I1 - I2) of the set pulse is proved to be a crucial parameter for set programming. We observe and analyze the cell characteristics with different I1 - I2 by means of thermal simulations and high-resolution transmission electron microscopy, which reveal that an incomplete set programming will occur when the proposed slow-down pulse is set with an improperly high I1 - I2. This will lead to an amorphous residue in the active region. We also discuss the programming method to avoid the set performance degradations. 展开更多
关键词 PCRAM Set Programming method and Performance Improvement of Phase change Random Access Memory Arrays
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Streamflow responses to climate change and LUCC in a semi-arid watershed of Chinese Loess Plateau 被引量:9
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作者 LI Qingyun SUN Yanwei +2 位作者 YUAN Wenlin LYU Subing WAN Fang 《Journal of Arid Land》 SCIE CSCD 2017年第4期609-621,共13页
Climate change and Land Use/Cover Change(LUCC) have been identified as two primary factors affecting watershed hydrological regime. This study analyzed the trends of streamflow, precipitation, air temperature and po... Climate change and Land Use/Cover Change(LUCC) have been identified as two primary factors affecting watershed hydrological regime. This study analyzed the trends of streamflow, precipitation, air temperature and potential evapotranspiration(PET) from 1962 to 2008 in the Jihe watershed in northwestern Loess Plateau of China using the Mann-Kendall test. The streamflow responses to climate change and LUCC were quantified independently by the elasticity method. The results show that the streamflow presented a dramatic decline with a turning point occurred in 1971, while the precipitation and PET did not change significantly. The results also show that the temperature rose markedly especially since 1990 s with an approximate increase of 1.74°C over the entire research period(1962–2008). Using land use transition matrix, we found that slope cropland was significantly converted to terrace between 1970 s and 1990 s and that forest cover increased relatively significantly because of the Grain for Green Project after 2000. The streamflow reduction was predominantly caused by LUCC and its contribution reached up to 90.2%, while the contribution of climate change to streamflow decline was only 9.8%. Although the analytical results between the elasticity method and linear regression model were not satisfactorily consistent, they both indicated that LUCC(human activity) was the major factor causing streamflow decline in the Jihe watershed from 1962 to 2008. 展开更多
关键词 streamflow LUCC climate change Mann-Kendall test elasticity method Loess Plateau
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Using modified Soil Conservation Service curve number method to simulate the role of forest in flood control in the upper reach of the Tingjiang River in China 被引量:3
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作者 LIN Wei YANG Fan +2 位作者 ZHOU Liang XU Jian-gang ZHANG Xing-qi 《Journal of Mountain Science》 SCIE CSCD 2017年第1期1-14,共14页
To improve flood control efficiency and increase urban resilience to flooding,the impacts of forest type change on flood control in the upper reach of the Tingjiang River(URTR) were evaluated by a modified model based... To improve flood control efficiency and increase urban resilience to flooding,the impacts of forest type change on flood control in the upper reach of the Tingjiang River(URTR) were evaluated by a modified model based on the Soil Conservation Service curve number(SCS-CN) method. Parameters of the model were selected and determined according to the comprehensive analysis of model evaluation indexes. The first simulation of forest reconstruction scenario,namely a coniferous forest covering 59.35km^2 is replaced by a broad-leaved forest showed no significant impact on the flood reduction in the URTR. The second simulation was added with 61.75km^2 bamboo forest replaced by broad-leaved forest,the reduction of flood peak discharge and flood volume could be improved significantly. Specifically,flood peak discharge of 10-year return period event was reduced to 7-year event,and the reduction rate of small flood was 21%-28%. Moreover,the flood volume was reduced by 9%-14% and 18%-35% for moderate floods and small floods,respectively. The resultssuggest that the bamboo forest reconstruction is an effective control solution for small to moderate flood in the URTR,the effect of forest conversion on flood volume is increasingly reduced as the rainfall amount increases to more extreme magnitude. Using a hydrological model with scenarios analysis is an effective simulation approach in investigating the relationship between forest type change and flood control. This method would provide reliable support for flood control and disaster mitigation in mountainous cities. 展开更多
关键词 Flood control Soil Conservation Service curve number method Forest type change Scenarios simulation Tingjiang River
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Trends in gravity changes from 2009 to 2013 derived from ground-based gravimetry and GRACE data in North China 被引量:3
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作者 Shen Chongyang Xuan Songbai +1 位作者 Zou Zhengbo Wu Guiju 《Geodesy and Geodynamics》 2015年第6期423-428,共6页
North China is a key region for studying geophysical progress. In this study, ground-based and Gravity Recovery and Climate Experiment(GRACE) gravity data from 2009 to 2013 are used to calculate the gravity change r... North China is a key region for studying geophysical progress. In this study, ground-based and Gravity Recovery and Climate Experiment(GRACE) gravity data from 2009 to 2013 are used to calculate the gravity change rate(GCR) using the polynomial fitting method. In general, the study area was divided into the Shanxi rift, Jing-Jin-Ji(Beijing-Tianjin-Hebei Province), and Bohai Bay Basin(BBB) regions. Results of the distribution of the GCR determined from ground-based gravimetry show that the GCR appears to be "negativepositive-negative" from west to east, which indicates that different geophysical mechanisms are involved in the tectonic activities of these regions. However, GRACE solutions are conducted over a larger spatial scale and are able to show a difference between southern and northern areas and a mass redistribution of land water storage. 展开更多
关键词 North China Ground-based gravimetry Gravity Recovery and Climate Experiment(GRACE) Polynomial fitting method Gravity changes rate Tectonic activities Geophysical mechanisms Mass redistribution
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Gravity changes and surface deformations due to faults with different geometry
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作者 白志明 王椿镛 申重阳 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第6期690-698,728,共10页
Based on the formulae of the gravity changes and surface deformations raised by the dislocation of a point source,the gravity changes and deformations caused by the dislocations of fault with arbitrary geometry are co... Based on the formulae of the gravity changes and surface deformations raised by the dislocation of a point source,the gravity changes and deformations caused by the dislocations of fault with arbitrary geometry are computed by using numerical method. The results show that both of the dislocation and the geometry of the fault plane are the basic elements that determine the gravity and deformation effects. Gravity changes, vertical deformations and apparent vertical deformations induced by the dislocation are alike in their characteristic patterns. The similarities and differences of these patterns provide us a probability in acquiring the gravity and deformation anomalies due to faulting from the observed data. Thus the geometric and kinematic features of the earthquake-generating faults can be appropriately distinguished and evaluated. 展开更多
关键词 numerical method fault dislocations arbitrary geometry gravity changes and deformations
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A one-step method for producing microencapsulated phase change materials 被引量:14
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作者 Yi Jin Waipeng Lee +1 位作者 Zenfira Musina Yulong Ding 《Particuology》 SCIE EI CAS CSCD 2010年第6期588-590,共3页
This short communication reports our recent work on the synthesis and characterisation ofmicrocapsules of phase change materials using silica as the shell material through a one-step method. The method uses no surfact... This short communication reports our recent work on the synthesis and characterisation ofmicrocapsules of phase change materials using silica as the shell material through a one-step method. The method uses no surfactants or dispersants for stabilising the capsules. The results show that the one-step method allows the tuning of the size and polydispersity of the capsules, and the use of different core materials. Analyses of the capsules show that they contain about 65% phase change materials. The results also suggest no need for a stabilising agent due to self-stabilisation by the amine groups. Further work is underway to investigate the mechanical and thermal properties of the microcapsules and the scale-up of the method. 展开更多
关键词 Microencapsulation Phase change materials One-step method Thermal energy storage
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Climate-growth relationship stability of Picea crassifolia on an elevation gradient,Qilian Mountain,Northwest China 被引量:2
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作者 LEI Jing-pin FENG Xiao-hui +2 位作者 SHI Zheng BAI Deng-zhong XIAO Wen-fa 《Journal of Mountain Science》 SCIE CSCD 2016年第4期734-743,共10页
Climate affects Picea crassifolia growth and climate change will lead to changes in the climate–growth relationship(i.e., the "divergence" phenomenon). However, standardization methods can also change the u... Climate affects Picea crassifolia growth and climate change will lead to changes in the climate–growth relationship(i.e., the "divergence" phenomenon). However, standardization methods can also change the understanding of such a relationship. We tested the stability of this relationship by considering several variables: 1) two periods(1952–1980 and 1981–2009), 2) three elevations(2700, 3000, and 3300 m), and 3) chronologies detrended using cubic splines with two different flexibilities. With increasing elevation, the climatic factor limiting the radial growth of Picea crassifolia shifted from precipitation to temperature. At the elevation of 2700 m, the relationship between radial growth and mean temperature of the previous December changed so that the more flexible spline had a greater precipitation signal. At the elevation of 3000 m, positive correlation of radial growth with mean temperature and precipitation in September of the previous year became more significant. At the elevation of 3300 m, positive correlation between radial growth and precipitation of the currentsummer and the previous spring and autumn was no longer significant, whereas the positive correlation between radial growth and temperature of the current spring and summer strengthened. The detrending with the most flexible spline enhanced the precipitation signal at 2700 m, while that with the least flexible spline enhanced the temperature signal at 3300 m. All results indicated that the divergence phenomenon was affected by the climatic signals in the chronologies and that it was most dependent on the detrending method. This suggests it is necessary to select a suitable spline bootstrap for studies of growth divergence phenomena. 展开更多
关键词 Climate change Detrending method Divergence problem Tree ring
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Research on Optimize Prediction Model and Algorithm about Chaotic Time Series
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作者 JIANGWei-jin XUYu-sheng 《Wuhan University Journal of Natural Sciences》 CAS 2004年第5期735-739,共5页
We put forward a chaotic estimating model, by using the parameter of the chaotic system, sensitivity of the parameter to inching and control the disturbance of the system, and estimated the parameter of the model by u... We put forward a chaotic estimating model, by using the parameter of the chaotic system, sensitivity of the parameter to inching and control the disturbance of the system, and estimated the parameter of the model by using the best update option. In the end, we forecast the intending series value in its mutually space. The example shows that it can increase the precision in the estimated process by selecting the best model steps. It not only conquer the abuse of using detention inlay technology alone, but also decrease blindness of using forecast error to decide the input model directly, and the result of it is better than the method of statistics and other series means. Key words chaotic time series - parameter identification - optimal prediction model - improved change ruler method CLC number TP 273 Foundation item: Supported by the National Natural Science Foundation of China (60373062)Biography: JIANG Wei-jin (1964-), male, Professor, research direction: intelligent compute and the theory methods of distributed data processing in complex system, and the theory of software. 展开更多
关键词 chaotic time series parameter identification optimal prediction model improved change ruler method
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Baring the Pain——The government and NGOs work to change outdated and cruel bear bile extraction methods
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作者 YIN PUMIN 《Beijing Review》 2006年第24期26-29,共4页
It's a subject that gets not only animal rights activists hot under the collar, but also the vast majority of caring people concerned about cruelty to animals. At a press conference in early 2006, the world's ... It's a subject that gets not only animal rights activists hot under the collar, but also the vast majority of caring people concerned about cruelty to animals. At a press conference in early 2006, the world's attention was once again drawn to the fate of Asiatic black bears (or moon bears) in China, so long tortured in the cruel practice of bile extraction. Only this 展开更多
关键词 Baring the Pain The government and NGOs work to change outdated and cruel bear bile extraction methods
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Impact of Climate Change on Maize Potential Productivity and the Potential Productivity Gap in Southwest China 被引量:8
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作者 赫迪 王靖 +4 位作者 戴彤 冯利平 张建平 潘学标 潘志华 《Journal of Meteorological Research》 SCIE 2014年第6期1155-1167,共13页
The impact of climate change on maize potential productivity and the potential productivity gap in Southwest China(SWC) are investigated in this paper.We analyze the impact of climate change on the photosynthetic,li... The impact of climate change on maize potential productivity and the potential productivity gap in Southwest China(SWC) are investigated in this paper.We analyze the impact of climate change on the photosynthetic,light-temperature,and climatic potential productivity of maize and their gaps in SWC,by using a crop growth dynamics statistical method.During the maize growing season from 1961 to 2010,minimum temperature increased by 0.20℃ per decade(p 〈 0.01) across SWC.The largest increases in average and minimum temperatures were observed mostly in areas of Yunnan Province.Growing season average sunshine hours decreased by 0.2 h day^(-1) per decade(p 〈 0.01) and total precipitation showed an insignificant decreasing trend across SWC.Photosynthetic potential productivity decreased by 298 kg ha^(-1)per decade(p 〈 0.05).Both light-temperature and climatic potential productivity decreased(p 〈 0.05) in the northeast of SWC,whereas they increased(p 〈 0.05) in the southwest of SWC.The gap between lighttemperature and climatic potential productivity varied from 12 to 2729 kg ha^(-1),with the high value areas centered in northern and southwestern SWC.Climatic productivity of these areas reached only 10%-24%of the light-temperature potential productivity,suggesting that there is great potential to increase the maize potential yield by improving water management in these areas.In particular,the gap has become larger in the most recent 10 years.Sensitivity analysis shows that the climatic potential productivity of maize is most sensitive to changes in temperature in SWC.The findings of this study are helpful for quantification of irrigation water requirements so as to achieve maximum yield potentials in SWC. 展开更多
关键词 climate change crop growth dynamics statistical method potential productivity sensitivity coefficient
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Impact localization of composite laminates based on weight function compensation localization algorithm of thin film sensors
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作者 Ying Wang Hongmei Li +5 位作者 Shaowei Lu Xingmin Liu Wei Li Xiaoqiang Wang Lu Zhang Qingxuan Wang 《International Journal of Smart and Nano Materials》 SCIE EI 2023年第2期139-154,共16页
Composite structures are sensitive to impact damage in practical engineering.Electric resistance change method(ERCM)is an ideal technique for damage monitoring of composite structures.Due to the anisotropy of fiber-re... Composite structures are sensitive to impact damage in practical engineering.Electric resistance change method(ERCM)is an ideal technique for damage monitoring of composite structures.Due to the anisotropy of fiber-resin matrix composites,impact location monitoring is difficult,and research on impact location of fiber composite laminates(FRPs)is limited.A preparation method of MXene/CNT/CuNps thin film sensor is proposed.According to the modeling simulation and theoretical calculation,the resistance change characteristics of the thin film sensor are obtained,the relationship between the impact distance and the resistance change is established,and the sensor array is designed.A three-point localization algorithm and a weight function compensation localization algorithm are proposed,which can improve the imaging accuracy of the impact position.The impact point location was observed and analyzed using ultrasonic C-scan technology.The results show that the weight function compensation positioning algorithm can accurately locate the impact of the composite structure,and the error in the X direction is 7.1%,the error in the Y direction is 0.03%,which verifies the effectiveness of the method. 展开更多
关键词 Electric resistance change method Mxene/CNT/CuNps film sensor damage localization Weighting function
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Evaluation of a multi-site weather generator in simulating precipitation in the Qiantang River Basin, East China
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作者 Yue-ping XU Chong MA Su-li PAN Qian ZHU Qi-hua RAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2014年第3期219-230,共12页
Recent years have seen a surge in assessment of potential impacts of climate change. As one of the most important tools for generating synthetic hydrological model inputs, weather generators have played an important r... Recent years have seen a surge in assessment of potential impacts of climate change. As one of the most important tools for generating synthetic hydrological model inputs, weather generators have played an important role in climate change impact analysis of water management. However, most weather generators like statistical downscaling model (SDSM) and long Ashton research station weather generator (LARS-WG) are designed for single site data generation. Considering the significance of spatial correlations of hydro-meteorological data, multi-site weather data generation becomes a necessity. In this study we aim to evaluate the performance of a new multi-site stochastic model, geo-spatial temporal weather generator (GIST), in simulating precipitation in the Qiantang River Basin, East China. The correlation matrix, precipitation amount and occurrence of observed and GiST-generated data are first compared for the evaluation process. Then we use the GiST model combined with the change factor method (CFM) to investigate future changes of precipitation (2071 2100) in the study area using one global climate model, Hadgem2 ES, and an extreme emission scenario RCP 8.5, The final results show that the simulated precipitation amount and occurrence by GiST matched their historical counterparts reasonably. The correlation coefficients between simulated and his- torical precipitations show good consistence as well. Compared with the baseline period (1961 1990), precipitation in the future time period (2071-2100) at high elevation stations will probably increase while at other stations decreases will occur. This study implies potential application of the GiST stochastic model in investigating the impact of climate change on hydrology and water resources. 展开更多
关键词 Climate change change factor method (CFM) Multi-site weather generator Qiantang River Basin
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