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中、低模量碳纤维在民用工业领域的应用 被引量:1
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作者 倪如青 沈协人 《合成纤维》 CAS 1995年第4期23-29,共7页
本文综述了中、低模量碳纤维在导电、电极、医疗、技术、无线电等领域的应用,着重介绍了导电碳纤维的性能、制造工艺及作为抗静电材料和加热体的应用.
关键词 碳纤维 民用工业 应用 机械性能 中模量 模量
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高模量沥青混凝土路面的力学性能 被引量:6
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作者 欧阳伟 顾威 王连广 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第4期593-596,共4页
研究了沥青混凝土路面中面层高温动态模量与车辙的关系.结果表明:提高路面中面层高温动态模量可以有效降低沥青混合料在荷载作用下的压、剪应变,加大中面层混合料向下传递荷载的扩散角,从而抵抗路面结构车辙病害;采用沥青混凝土外掺剂... 研究了沥青混凝土路面中面层高温动态模量与车辙的关系.结果表明:提高路面中面层高温动态模量可以有效降低沥青混合料在荷载作用下的压、剪应变,加大中面层混合料向下传递荷载的扩散角,从而抵抗路面结构车辙病害;采用沥青混凝土外掺剂提高混凝土高温动态模量,性能明显优于SBS改性沥青的混合料. 展开更多
关键词 道路工程 模量沥青混凝土 车辙试验 面层模量 剪切应变
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Research on Yield and Quality of Hybrid Rice under Efficient Application Amount of Phosphorus and Potassium 被引量:3
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作者 熊洪 徐富贤 +4 位作者 朱永川 张林 郭晓艺 刘茂 周兴兵 《Agricultural Science & Technology》 CAS 2012年第2期343-350,共8页
[Objective] Application of P and K was not reasonable in southwest rice producing area, with no effective method for guiding application of P and K. This study aimed to conduct experiments with the same N application ... [Objective] Application of P and K was not reasonable in southwest rice producing area, with no effective method for guiding application of P and K. This study aimed to conduct experiments with the same N application and different P and K application in different ecological points, to explore a scientific and efficient management method of P and K nutrients and provide guidance for application of P and K in rice production. [Method] Hybrid rice Chuanxiang9838 was used as experimental material to study the relationship among application amount of P and K, utilization rates of P and K, rice yield and rice quality in seven ecological points of four provinces (municipalities) including Sichuan, Chongqing, Yunnan and Guizhou. The application amount per hectare of P was 37.5, 75, 112.5 and 150 kg, respectively; the application amount per hectare of K was 45, 135 and 180 kg, respectively. A total of 10 treatments were set for split-plot design with three replications. [Result] Yield of Chuanxiang9838 significantly varied in different experimental locations and under different levels of P and K, interaction of ecological point and different P and K treatments varied significantly. Yield had reached the maximum in ecological point of Yunnan Binchuan and in treatment with application of N 150 kg P 75 kg K 90 kg. Efficient utilization rates of P and K varied in each ecological point, efficient application amount of P and K in Sichuan Dongpo, Sichuan Luxian, Guizhou Xiaohe and Chongqing Yongchuan was the same, while that in Sichuan Guanghan, Sichuan Zhongjiang and Yunnan Binchuan was different. The main objective of high-yield rice production was to increase the number of effective panicles per hectare and seed setting rate. Rice quality was clustered into 2 categories by locations and 6 categories by treatments. [Conclusion] Prediction models of efficient application of P and K in rice production were established, which provided guidance for high-yield rice production and rational and efficient utilization of P and K in southwest rice area. 展开更多
关键词 Phosphorus and potassium nutrients Efficient application amount Mathematic model Mid-season hybrid rice
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An automatical infill shot method for uniform imaging of target layer 被引量:4
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作者 赵虎 尹成 +3 位作者 侯朋军 蒲龙川 黄勇 苑国辉 《Applied Geophysics》 SCIE CSCD 2013年第2期222-228,237,共8页
Seismic imaging quality is critical to describing reservoirs. There are many methods that can improve imaging quality; some rely on advanced processing means, whereas others rely on changing the field acquisition meth... Seismic imaging quality is critical to describing reservoirs. There are many methods that can improve imaging quality; some rely on advanced processing means, whereas others rely on changing the field acquisition methods. However, most of the acquisition methods focus on improving imaging by using infill shots without considering the target-layer illumination energy. Moreover, total infill shooting greatly increases the acquisition cost. In this paper, we present a new method for maximizing the contribution to the target shadow area illumination by automatic local infill shooting. Thus, we designed 2D and 3D models and obtained the depth migration section by forward modeling, infill shots, depth migration, etc. The model results also show that by choosing the most appropriate number of shot points, we can enhance the shadow area energy and improve the target-layer imaging quality at low cost. 展开更多
关键词 Infill shooting forward modeling target-layer imaging survey design
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赫氏在JEC巴黎复材展上推出最新一代碳纤维HexTow IM10
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作者 忆秋 《航空制造技术》 2010年第9期18-18,共1页
在2010JEC巴黎复合材料展上,赫氏推出了最新的中模量碳纤维产品HexTow IM10,该材料可视为中模量碳纤维的最新突破,在提供最高的抗拉强度的同时,又在所有其他性能(如剪切强度)上保持均衡,从而使设计者在强度和刚度的临界应用中达... 在2010JEC巴黎复合材料展上,赫氏推出了最新的中模量碳纤维产品HexTow IM10,该材料可视为中模量碳纤维的最新突破,在提供最高的抗拉强度的同时,又在所有其他性能(如剪切强度)上保持均衡,从而使设计者在强度和刚度的临界应用中达到较高的安全边际。 展开更多
关键词 碳纤维 巴黎 JEC 复合材料 抗拉强度 纤维产品 剪切强度 中模量
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基于中面层模量提升的路面结构性能补强技术及应用 被引量:3
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作者 陈刊 金光来 冯雯雯 《公路交通科技(应用技术版)》 CSCD 北大核心 2020年第10期39-44,共6页
为了提升路面结构的长期性能,本文从结构层模量提升角度出发,从力学机理上分析中面层模量对路面结构长期性能的影响,进一步拟定路面结构性补强方案,并与原始路面结构进行对比,然后结合实体工程,论证方案的可行性。结果表明:通过提升中... 为了提升路面结构的长期性能,本文从结构层模量提升角度出发,从力学机理上分析中面层模量对路面结构长期性能的影响,进一步拟定路面结构性补强方案,并与原始路面结构进行对比,然后结合实体工程,论证方案的可行性。结果表明:通过提升中面层模量,能够提高路面结构抗车辙和抗疲劳性能,工后检测表明,结构性补强技术实施路段路用性能良好,通过提高中面层模量来提升路面结构长期性能是可行的。 展开更多
关键词 沥青路面 结构性补强 面层模量 长期性能提升
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Current Status and Development Strategies of Chinese Cosmetic Industry
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作者 里筱竹 江滨 +1 位作者 王一涛 史录文 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第1期72-74,共3页
Current status and existing problems in the Chinese cosmetic industry areanalyzed from the aspects of industry scale, technology and management level, R&D investment andhuman resources. Strategies to promote the i... Current status and existing problems in the Chinese cosmetic industry areanalyzed from the aspects of industry scale, technology and management level, R&D investment andhuman resources. Strategies to promote the industry are also put forward, such as increasing entrybarrier to optimize industry structure, tightening regulatory controls to improve quality assurance,fostering innovation and actively exploring modes of collaboration, and training more technical andmanaging professionals. 展开更多
关键词 COSMETIC cosmetic industry development strategies
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The quantified analysis of China's GM cotton yield capacity by C-D function and stochastic frontier model
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作者 张涛 薛宝娣 《Hunan Agricultural Science & Technology Newsletter》 2004年第1期11-13,共3页
Using a modified C D function and stochastic frontier model, the paper analyzed China's cotton yield capacity and found that the yield and technical efficiency of China's cotton planting system can be increas... Using a modified C D function and stochastic frontier model, the paper analyzed China's cotton yield capacity and found that the yield and technical efficiency of China's cotton planting system can be increased by the use of genetically modified (GM) varieties. 展开更多
关键词 GM cotton yield capacity C D function stochastic frontier model
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Using ^(137)Cs Tracer Technique to Evaluate Erosion and Deposition of Black Soil in Northeast China 被引量:34
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作者 FANG Hua-Jun YANG Xue-Ming +1 位作者 ZHANG Xiao-Ping LIANG Ai-Zhen 《Pedosphere》 SCIE CAS CSCD 2006年第2期201-209,共9页
Soil and water losses through erosion have been serious in the black soil region of Northeast China. Therefore, a sloping cultivated land in Songnen Plain was selected as a case study to: 1) determine the ^137Cs ref... Soil and water losses through erosion have been serious in the black soil region of Northeast China. Therefore, a sloping cultivated land in Songnen Plain was selected as a case study to: 1) determine the ^137Cs reference inventory in the study area; 2) calculate erosion and deposition rates of black soil on different slope locations; 3) conduct a sensitivity analysis of some model parameters; and 4) compare overall outputs using four different models. Three transects were set in the field with five slope locations for each transect, including summit, shoulder-slope, back-slope, foot-slope, and toe-slope. Field measurements and model simulation were used to estimate a bomb-derived ^137Cs reference inventory in the study area. Soil erosion and deposition rates were estimated using four ^137Cs models and percentage of ^137Cs loss/gain. The ^137Cs reference value in the study area was 2 232.8 Bq m^-2 with ^137Cs showing a clear topographic pattern, decreasing from the summit to shoulder-slope, then increasing again at the foot-slope and reaching a maximum at the toe-slope, Predicted soil redistribution rates for different slope locations varied. Among models, the Yang Model (YANG-M) overestimated erosion loss but underestimated deposition. However, the standard mass balance model (MBM1) gave predictions similar to a mass balance model incorporating soil movement by tillage (MBM2). Sensitivity analysis of the proportion factor and distribution pattern of ^137Cs in the surface layer demonstrated the impact of ^137Cs enrichment on calculation of the soil erosion rate. Factors influencing the redistribution of fallout ^137Cs in landscape should be fully considered as calculating soil redistribution rate using ^137Cs technique. 展开更多
关键词 black soil cesium-137 (^137Cs) Northeast China quantitative models soil erosion
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Numerical simulation of deepwater deployment for offshore structures with deploying cables 被引量:1
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作者 胡小舟 刘少军 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期922-930,共9页
Deepwater deployment of offshore structures in different sea states was investigated. The whole deployment system was modeled as a lumped mass model, and discretization scheme for cable geometry and methodology for ca... Deepwater deployment of offshore structures in different sea states was investigated. The whole deployment system was modeled as a lumped mass model, and discretization scheme for cable geometry and methodology for calculating the internal and external force acting on deploying cable were presented. The deployment model suitable for the time-varying length of deploying cable was specified. The free-surface flow fields together with the ship motions were used to calculate dynamic tension in the deploying cable during deployment of the structure. The deployment of deep sea mining system which was a typical subsea working system was employed. Based on lumped mass analysis model and parameters of deep sea mining system, numerical simulations were performed, and dynamic load and dynamic amplification factor(DAF) with different cable parameters, deploying velocities and sea states were obtained. It is shown that cable parameters and amplitudes of ocean waves can significantly influence the dynamic load and DAF, and the time-varying natural period of deploying system is a dominant factor, while the effect of deploying velocity is not obvious. 展开更多
关键词 deployment cable dynamic load dynamic amplification factor
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Modal analysis on transverse vibration of axially moving roller chain coupled with lumped mass 被引量:4
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作者 许立新 杨玉虎 +1 位作者 常宗瑜 刘建平 《Journal of Central South University》 SCIE EI CAS 2011年第1期108-115,共8页
The modal characteristics of the transverse vibration of an axially moving roller chain coupled with lumped mass were analyzed.The chain system was modeled by using the multi-body dynamics theory and the governing equ... The modal characteristics of the transverse vibration of an axially moving roller chain coupled with lumped mass were analyzed.The chain system was modeled by using the multi-body dynamics theory and the governing equations were derived by means of Lagrange's equations.The effects of the parameters,such as the axially moving velocity of the chain,the tension force,the weight of lumped mass and its time-variable assign position in chain span,on the modal characteristics of transverse vibration for roller chain were investigated.The numerical examples were given.It is found that the natural frequencies and the corresponding mode shapes of the transverse vibration for roller chain coupled with lumped mass change significantly when the variations of above parameters are considered.With the movement of the chain strand,the natural frequencies present a fluctuating phenomenon,which is different from the uniform chain.The higher the order of mode is,the greater the fluctuating magnitude and frequency are. 展开更多
关键词 roller chain modal analysis transverse vibration lumped mass
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Effects of continuous casting mould fluxes on reducing longitudinal and star cracks on a slab surface 被引量:1
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作者 WANGQian WANGYu +4 位作者 CHIJinghao XIEBing HEYuming ZHUBing CHENWenman 《Journal of Chongqing University》 CAS 2004年第1期65-68,共4页
In the continuous casting production of medium carbon steel (whose mass fraction of carbon is 0.09 % to 0.16 %) and high strength low alloy steel (whose mass fraction of Mn is 0.90 % to 1.40 %), flecks occurring the m... In the continuous casting production of medium carbon steel (whose mass fraction of carbon is 0.09 % to 0.16 %) and high strength low alloy steel (whose mass fraction of Mn is 0.90 % to 1.40 %), flecks occurring the most often are usually longitudinal and star cracks. In additional to the employment of a galvanized plate mould, two kinds of fluxes with special properties were studied and used to harmonize the conflicts between the function of heat transfer and lubrication. An industrial application revealed that the crystallizing temperature (Tc) and crystal ratio (R) of fluxes have a crucible effect on impeding the occurrence of above defects on a slab surface. In the case of slab section (180 to 240) mm(1000 to 1400) mm and casting speed Vc of (0.7 to 1.2) m/min, the optimized parameters of fluxes are Tc of (1170 to 1190) ℃, R of 80 % to 95 % for medium carbon steel, and Tc of (1100 to 1150) ℃, plus R of 40 % to 60 % for high strength low alloy steel. 展开更多
关键词 continuous casting mould flux star crack longitudinal crack
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A Modified Groundwater Module in SWAT for Improved Streamflow Simulation in a Large, Arid Endorheic River Watershed in Northwest China 被引量:6
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作者 JIN Xin HE Chansheng +1 位作者 ZHANG Lanhui ZHANG Baoqing 《Chinese Geographical Science》 SCIE CSCD 2018年第1期47-60,共14页
Interactions between surface water and groundwater are dynamic and complex in large endorheic river watersheds in Northwest China due to the influence of both irrigation practices and the local terrain. These interact... Interactions between surface water and groundwater are dynamic and complex in large endorheic river watersheds in Northwest China due to the influence of both irrigation practices and the local terrain. These interactions interchange numerous times throughout the middle reaches, making streamflow simulation a challenge in endorheic river watersheds. In this study, we modified the linear-reservoir groundwater module in SWAT(Soil and Water Assessment Tools, a widely used hydrological model) with a new nonlinear relationship to better represent groundwater processes; we then applied the original SWAT and modified SWAT to the Heihe River Watershed, the second largest endorheic river watershed in Northwest China, to simulate streamflow. After calibrating both the original SWAT model and the modified SWAT model, we analyzed model performance during two periods: an irrigation period and a non-irrigation period. Our results show that the modified SWAT model with the nonlinear groundwater module performed significantly better during both the irrigation and non-irrigation periods. Moreover, after comparing different runoff components simulated by the two models, the results show that, after the implementation of the new nonlinear groundwater module in SWAT, proportions of runoff components changed-and the groundwater flow had significantly increased, dominating the discharge season. Therefore, SWAT coupled with the non-linear groundwater module represents the complex hydrological process in the study area more realistically. Moreover, the results for various runoff components simulated by the modified SWAT models can be used to describe the hydrological characteristics of lowland areas. This indicates that the modified SWAT model is applicable to simulate complex hydrological process of arid endorheic rivers. 展开更多
关键词 Soil and Water Assessment Tools (SWAT) GROUNDWATER irrigation streamflow Heihe River
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Effects of China's OFDI on Host Countries' Environmental Quality 被引量:1
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作者 刘玉博 吴万宗 《China Economist》 2017年第5期110-123,共14页
From a FDI source country perspective, this paper reveals the effect of Chinas OFDI on host countries' environmental quality. Based on the Copeland-Taylor model, this paper creates a theoretical mechanism to demon... From a FDI source country perspective, this paper reveals the effect of Chinas OFDI on host countries' environmental quality. Based on the Copeland-Taylor model, this paper creates a theoretical mechanism to demonstrate how Chinas OFDI affects host countries' pollution intensity and environmental quality and carries out an empirical analysis based on Chinas OFDI data of 2003-2014 and the economic development index data of 168 host countries. Since Chinas OFDI is differentiated for countries of various income levels, this paper f Urther conducts a sub-sample empirical test on the income level of host countries. The result shows that Chinas OFDI growth generally induces an increase in total pollution emissions in host countries but significantly reduces per capita emissions and thus improves local environmental quality. Sub-sample regression result shows that whether in terms of total or per capita emissions, Chinas OFDI has a much more significant effect in improving the environmental quality of high-income countries. 展开更多
关键词 OFDI environmental quality Copeland-Taylor model
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Kinetic Energy Budget Equations of Rotational and Divergent Flow in Terrain-following Coordinates 被引量:1
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作者 CAO Jie SUN Ji-Song +1 位作者 GAO Shou-Ting CUI Xiao-Peng 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第3期149-153,共5页
In this study, kinetic energy budget equations of rotational and divergent flow in pressure coordinates are derived on terrain-following coordinates. The new formulation explicitly shows the terrain effects and can be... In this study, kinetic energy budget equations of rotational and divergent flow in pressure coordinates are derived on terrain-following coordinates. The new formulation explicitly shows the terrain effects and can be applied directly to model-simulated dynamic and thermodynamic fields on the model's original vertical grid. Such application eliminates interpolation error and avoids errors in virtual weather systems in mountainous areas. These advantages and their significance are demonstrated by a numerical study in terrain-following coordinates of a developing vortex after it moves over the Tibetan Plateau in China. 展开更多
关键词 terrain-following coordinates kinetic energy southwest vortex streamfunction velocity potential
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Development of neutron moisture gauge in China 被引量:1
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作者 Zhao Jingwu Liu Shengkang Zhang Zhiping 《Engineering Sciences》 EI 2009年第4期45-50,共6页
According to measuring mode (in-hopper,surface,transmitted and scattered neutron moisture gauge),this paper introduced the development and application of neutron moisture gauge in China since 1970s.
关键词 neutron moisture gauge neutron detector neutron source moisture content density compensation
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A Novel Feature-based Method for Sentiment Analysis of Chinese Product Reviews 被引量:5
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作者 LIU Lizhen SONG Wei +2 位作者 WANG Hanshi LI Chuchu LU Jingli 《China Communications》 SCIE CSCD 2014年第3期154-164,共11页
Sentiment analysis of online reviews and other user generated content is an important research problem for its wide range of applications.In this paper,we propose a feature-based vector model and a novel weighting alg... Sentiment analysis of online reviews and other user generated content is an important research problem for its wide range of applications.In this paper,we propose a feature-based vector model and a novel weighting algorithm for sentiment analysis of Chinese product reviews.Specifically,an opinionated document is modeled by a set of feature-based vectors and corresponding weights.Different from previous work,our model considers modifying relationships between words and contains rich sentiment strength descriptions which are represented by adverbs of degree and punctuations.Dependency parsing is applied to construct the feature vectors.A novel feature weighting algorithm is proposed for supervised sentiment classification based on rich sentiment strength related information.The experimental results demonstrate the effectiveness of the proposed method compared with a state of the art method using term level weighting algorithms. 展开更多
关键词 sentiment analysis sentimentstrength opinion mining dependency parsing
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Coordinate-Momentum Intermediate Representation and Marginal Distributions of Quantum Mechanical Bivariate Normal Distribution
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作者 FAN Hong-Yi LOU Sen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第3期613-616,共4页
We introduce bivariate normal distribution operator for state vector [ψ) and find that its marginal distribution leads to one-dimensional normal distribution corresponding to the measurement probability |λ,v〈x|... We introduce bivariate normal distribution operator for state vector [ψ) and find that its marginal distribution leads to one-dimensional normal distribution corresponding to the measurement probability |λ,v〈x|.ψ〉|^2, where |x〉λ,v is the coordinate-momentum intermediate representation. As a by-product, the one-dimensional normal distribution in statistics can be explained as a Radon transform of two-dimensional Gaussian function. 展开更多
关键词 coordinate-momentum intermediate representation bivariate normal distribution
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Preliminary Evaluation of Cloud Fraction Simulations by GAMIL2 Using COSP 被引量:4
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作者 DONG Li LI Li-Juan +2 位作者 HUANG Wen-Yu WANG Yong WANG Bin 《Atmospheric and Oceanic Science Letters》 2012年第3期258-263,共6页
The Cloud Feedback Model Intercomparisons Project (CFMIP) Observation Simulator Package (COSP) is adopted in the Grid-point Atmospheric Model of IAP LASG (GAMIL2) during CFMIP at Phase II to evaluate the model cloud f... The Cloud Feedback Model Intercomparisons Project (CFMIP) Observation Simulator Package (COSP) is adopted in the Grid-point Atmospheric Model of IAP LASG (GAMIL2) during CFMIP at Phase II to evaluate the model cloud fractions in a consistent way with satellite observations. The cloud simulation results embedded in the Atmospheric Model Intercomparison Project (AMIP) control experiment are presented using three satellite simulators: International Satellite Cloud Climatology Project (ISCCP), Moderate Resolution Imaging Spectroradiometer (MODIS), and Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) lidar onboard the Cloud- Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). Overall, GAMIL2 can produce horizontal distributions of the low cloud fraction that are similar to the satellite observations, and its similarities to the observations on different levels are shown in Taylor diagrams. The discrepancies among satellite observations are also shown, which should be considered during evaluation. 展开更多
关键词 COSP GAMIL cloud fraction satellite simu- lator
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Global Convergence of a New Restarting Three Terms Conjugate Gradient Method for Non-linear Optimizations 被引量:1
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作者 SUN Qing-ying SANG Zhao-yang TIAN Feng-ting 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第1期69-76,共8页
In this note,by combining the nice numerical performance of PR and HS methods with the global convergence property of FR method,a class of new restarting three terms conjugate gradient methods is presented.Global conv... In this note,by combining the nice numerical performance of PR and HS methods with the global convergence property of FR method,a class of new restarting three terms conjugate gradient methods is presented.Global convergence properties of the new method with two kinds of common line searches are proved. 展开更多
关键词 nonlinear programming restarting three terms conjugate gradient method forcing function reverse modulus of continuity function convergence
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