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黄骅传统面花模子造型艺术解析
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作者 卞培 《现代装饰(理论)》 2014年第8期138-138,共1页
黄骅面花模子其独特的民俗艺术形式,广泛的题材特征、夸张的表现力与独特地造型特点反映了本土的民俗文化,展示了区域民间本原艺术体系与造型体系特征,表达了民族民众的本土文化特色和情感。
关键词 体系特征 艺术体系 花模 造型特点 民俗艺术 艺术造型 文化心理 艺术韵味 民间美术 河北省黄骅市
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横针机构的动态仿真研究(英文) 被引量:3
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作者 李瑞琴 邹慧君 郭为忠 《系统仿真学报》 CAS CSCD 2004年第2期350-352,共3页
对用于多功能缝纫机中的横针机构进行了动态仿真研究。编制的横针机构的仿真软件实现了全部结构参数的动态输入,动态仿真。并可根据对横针距的设计要求,快速反求花模凸轮的轮廓。不同的横针距与直针距相配合,可以实现任意给定的缝纫线... 对用于多功能缝纫机中的横针机构进行了动态仿真研究。编制的横针机构的仿真软件实现了全部结构参数的动态输入,动态仿真。并可根据对横针距的设计要求,快速反求花模凸轮的轮廓。不同的横针距与直针距相配合,可以实现任意给定的缝纫线迹。求出的花模凸轮的廓线数据,可作为花模电子凸轮的设计参数,为横针机构的机电一体化提供了设计基础。 展开更多
关键词 横针机构 花模凸轮 针迹 仿真
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Application of Fuzzy Comprehensive Evaluation Method Based on Entropy Weight Theory in Evaluation of Salt Tolerance of Cotton 被引量:6
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作者 张国伟 刘瑞显 +1 位作者 杨长琴 杨富强 《Agricultural Science & Technology》 CAS 2014年第9期1441-1445,1481,共6页
[Objective] The aim was to propose a new entropy weight fuzzy compre- hensive evaluation method for assessing cotton salt tolerance, realizing the objective, accurate and comprehensive evaluation of salt tolerance of ... [Objective] The aim was to propose a new entropy weight fuzzy compre- hensive evaluation method for assessing cotton salt tolerance, realizing the objective, accurate and comprehensive evaluation of salt tolerance of cotton. [Method] A sand culture experiment under salt stress of 150 mmol/L of NaCI was designed. The in- dicator weight was determined with the entropy weight fuzzy comprehensive evalu- ation method, based on the salt injury index of indicators. The salt tolerance of cotton was evaluated comprehensively. [Result] At the germination stage, the entropy and weight of salt injury index of germination energy, vigor index, hypocotyl length and fresh weight were highest, followed by germination rate and germination index, and of root length were lowest. At the seedling stage, the entropy and weight of salt injury index of plasma membrane permeability, root vigor and leaf expansion rate were highest, followed by plant height and net photosynthetic rate, and of shoot dry weight and root dry weight were lowest. The salt tolerance of cotton differed a- mong growth stages and cultivars. Among the 11 cultivars, CCRI-44 and CCRI-75 were steadily salt-tolerant at both germination and seedling stages; CCRI-17, Sumi- an 22, Sumian 15 and Dexiamianl had a stable moderate salt tolerance; while Sumian 12 and Simian 3 were steadily salt-sensitive. [Conclusion] The evaluated result was objective and exact, which indicated that this method could be used in comprehensive evaluation of salt tolerance of cotton. 展开更多
关键词 Entropy weight method Fuzzy comprehensive evaluation COTTON Salt tolerance
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五台风俗民情
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作者 郝晓丽 《五台山研究》 1986年第5期46-48,共3页
五台县地域辽阔,人口众多,县境南北长达150华里。以黄土坡为界有上下五台之分:黄土坡以北为“上五台”,以南为“下五台”。因此,五台县的风俗民情是丰富多彩的,下五台杂有原平。定襄的乡俗特点,最北部则与繁峙、代县的风俗民情有相似之... 五台县地域辽阔,人口众多,县境南北长达150华里。以黄土坡为界有上下五台之分:黄土坡以北为“上五台”,以南为“下五台”。因此,五台县的风俗民情是丰富多彩的,下五台杂有原平。定襄的乡俗特点,最北部则与繁峙、代县的风俗民情有相似之处;一般以台城一带的风俗民情作为五台县风俗民情的代表。 展开更多
关键词 风俗民情 五台 花模 定襄 六月会 黛螺顶 结婚典礼 丧葬仪式 余味无穷 英俊潇洒
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FOUR-AXIS WIRE-EDM SIMULATION OF COMPLICATED MODELS
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作者 安鲁陵 汪炜 +2 位作者 周来水 翟洪军 刘绍琼 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第4期322-328,共7页
In the verification of wire electrical discharge machining (EDM), the motion and the performance of the wire-EDM system are analyzed. The maximum inclining angle of the wire is calculated. The relevant judgment meth... In the verification of wire electrical discharge machining (EDM), the motion and the performance of the wire-EDM system are analyzed. The maximum inclining angle of the wire is calculated. The relevant judgment methods are used for the collision between the wire, the fixture, and the machining table. In the wire-EDM simulation, the generated solid model can he used to investigate programming results and to check the machining accuracy. The generation algorithm for the solid model in the simulation is solved based on Boolean operations. The wire swept volume for each cutting step is united to form the entire wire swept volume. Through Boolean subtraction between the stock model and the entire wire swept volume, the solid model in the wire-EDM simulation is generated. The method is also suitable for the wire path intersection occurred in cutting cone-shaped models. Finally, experiments are given to prove the method. 展开更多
关键词 wire electrical discharge machining solid model Boolean operation
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激光技术对家具镶嵌加工
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《新疆林业》 1989年第2期29-29,共1页
苏联利用二氧化碳气体批量放出的激光具有高度可靠的照射性能,制造了一种装饰家具板面的设备。 这种设备要与磨床配套使用,只要有可调节功率(5——60瓦)的辐射源,就足以在木板上留下痕迹。他们把绘上所需花纹图案的漏花模板盖在家具板... 苏联利用二氧化碳气体批量放出的激光具有高度可靠的照射性能,制造了一种装饰家具板面的设备。 这种设备要与磨床配套使用,只要有可调节功率(5——60瓦)的辐射源,就足以在木板上留下痕迹。他们把绘上所需花纹图案的漏花模板盖在家具板面上。 展开更多
关键词 激光技术 波长范围 花纹图案 二氧化碳气体 花模 工作效率
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DF-2模具钢
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《热处理技术与装备》 2016年第3期60-60,共1页
一胜百ASSAB DF2钢材为锰-铬-钨的常用油淬工具合金钢,是高质量的冷作工具钢。加工性好;热处理尺寸稳定;优良的机械加工性;淬硬时,优良的尺寸稳定性;淬硬和回火后,表面有很高的硬度与机体韧性的良好配合;淬透性极好;耐热熔损性良好;切... 一胜百ASSAB DF2钢材为锰-铬-钨的常用油淬工具合金钢,是高质量的冷作工具钢。加工性好;热处理尺寸稳定;优良的机械加工性;淬硬时,优良的尺寸稳定性;淬硬和回火后,表面有很高的硬度与机体韧性的良好配合;淬透性极好;耐热熔损性良好;切削性较SKD61稍有降低;抗热裂性能好。 展开更多
关键词 压铸模具 冷作工具钢 机械加工性 淬硬 压印模 挤压模 DF-2 抗热裂性 疲劳开裂 花模
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Numerical modeling of seabed morphological effects from the construction of artificial islands in Danzhou, Hainan
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作者 英晓明 贾后磊 +1 位作者 曹玲珑 谢健 《Marine Science Bulletin》 CAS 2014年第2期37-45,共9页
Haihua Islands is a large artificial island in Danzhou, Hainan. The construction of Haihua Islands changes the hYdrodynamic environment of Yangpu waters, and further affects its morphological change. Delft3D is used t... Haihua Islands is a large artificial island in Danzhou, Hainan. The construction of Haihua Islands changes the hYdrodynamic environment of Yangpu waters, and further affects its morphological change. Delft3D is used to set up a two dimensional nested hydrodynamic and sediment model for Yangpu waters in this paper, and this paper focuses on simulating the velocity and morphological change due to the construction of Haihua Islands after the verification of the model. The seabed deposition is small because of low suspended sediment concentration and less sand source near Yangpu waters. The bed level erodes in the south area of Xiaochan Reef and the Yangpu channel due to the velocity increase in the area. 展开更多
关键词 Haihua Islands seabed morphological effect numerical modeling
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Effects of Spark Ignition Engine Operating Parameters on Its Cyclic Variation ——Modeling and Simulation
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作者 纪常伟 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期332-336,共5页
An engine cyclic variation model has been built by using the residual gas temperature for the n th cycle as the input of the model, through constant pressure intake process, adiabatic compression process, constan... An engine cyclic variation model has been built by using the residual gas temperature for the n th cycle as the input of the model, through constant pressure intake process, adiabatic compression process, constant volume combustion process, adiabatic expansion process, adiabatic blow down process and constant pressure exhaust process to approximate the thermodynamic processes in the cylinder, finally the residual gas temperature for the ( n+1) th cycle can be estimated. Because of the adding of engine operating parameters such as engine speed, spark advance, equivalence ratio, intake air pressure, intake air temperature to the model, effects of these parameters on cyclic variation can be estimated quantitatively. Since residual gas temperature fluctuation between cycles reflects the circumstances of engine cyclic variation, parameters to which residual gas temperature is sensitive are most likely used as the means to control cyclic variation. Model simulation shows that for the nearly stiochiometric mixture, cyclic variation is not obvious or even quite stable, but for the lean mixture, under the circumstances of partial load and larger spark advances, engine cyclic variations occur chaotically or with bifurcation. 展开更多
关键词 cyclic variation MODELING residual gas temperature spark ignition engine
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Adsorption Dynamics of Calyx Aroma onto Basic Tea in Scenting Process of Calyx-scented Tea 被引量:1
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作者 陈昌辉 《Agricultural Science & Technology》 CAS 2012年第9期2017-2020,共4页
[Objective] The paper was to study adsorption dynamics of calyx aroma onto basic tea in scenting process of calyx-scented tea, so as to increase aroma and quality of products. [Method] Adsorption experiment was carrie... [Objective] The paper was to study adsorption dynamics of calyx aroma onto basic tea in scenting process of calyx-scented tea, so as to increase aroma and quality of products. [Method] Adsorption experiment was carried out in a hermetic container, and the effect of calyx amount, contact time, moisture content of basic tea and temperature on the scenting process was studied. [Result] The optimal moisture and temperature for scenting process was 4% and 10 ℃, respectively. [Conclusion] The scenting process accorded pseudo-first-order kinetic model, and the adsorption dynamic data of total process could better fit pseudo-second-order kinetic model. 展开更多
关键词 TEA Odor and taste threshold KINETIC ADSORPTION Sensory panel Calyxcanthus
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Numerical Simulation of Typhoon Muifa(2011) Using a Coupled Ocean-Atmosphere-Wave-Sediment Transport(COAWST) Modeling System 被引量:11
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作者 LIU Na LING Tiejun +3 位作者 WANG Hui ZHANG Yunfei GAO Zhiyi WANG Yi 《Journal of Ocean University of China》 SCIE CAS 2015年第2期199-209,共11页
The newly developed Coupled Ocean-Atmosphere-Wave-Sediment Transport(COAWST) Modeling System is applied to investigate typhoon-ocean interactions in this study. The COAWST modeling system represents the state-of-the-a... The newly developed Coupled Ocean-Atmosphere-Wave-Sediment Transport(COAWST) Modeling System is applied to investigate typhoon-ocean interactions in this study. The COAWST modeling system represents the state-of-the-art numerical simulation technique comprising several coupled models to study coastal and environmental processes. The modeling system is applied to simulate Typhoon Muifa(2011), which strengthened from a tropical storm to a super typhoon in the Northwestern Pacific, to explore the heat fluxes exchanged among the processes simulated using the atmosphere model WRF, ocean model ROMS and wave model SWAN. These three models adopted the same horizontal grid. Three numerical experiments with different coupling configurations are performed in order to investigate the impact of typhoon-ocean interaction on the intensity and ocean response to typhoon. The simulated typhoon tracks and intensities agree with observations. Comparisons of the simulated variables with available atmospheric and oceanic observations show the good performance of using the coupled modeling system for simulating the ocean and atmosphere processes during a typhoon event. The fully coupled simulation that includes a ocean model identifies a decreased SST as a result of the typhoon-forced entrainment. Typhoon intensity and wind speed are reduced due to the decrease of the sea surface temperature when using a coupled ocean model. The experiments with ocean coupled to atmosphere also results in decreased sea surface heat flux and air temperature. The heat flux decreases by about 29% compared to the WRF only case. The reduction of the energy induced by SST decreases, resulting in weakening of the typhoon. Coupling of the waves to the atmosphere and ocean model induces a slight increase of SST in the typhoon center area with the ocean-atmosphere interaction increased as a result of wave feedback to atmosphere. 展开更多
关键词 COAWST modeling system typhoon Muifa WRF ROMS SWAN
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Modeling of the Dyeing Uptake Rate for Direct Dyestuff on Cotton in Batch Dyeing Process Based on Grey System Theory
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作者 张建新 田彦杰 张永兴 《Journal of Donghua University(English Edition)》 EI CAS 2013年第6期498-503,共6页
The grey system theory, with the characteristics of fewer modeling data and higher accuracy, was employed to model the batch dyeing process for the purpose of accurate online control. The GM(1, 1) and GM (0, N) mo... The grey system theory, with the characteristics of fewer modeling data and higher accuracy, was employed to model the batch dyeing process for the purpose of accurate online control. The GM(1, 1) and GM (0, N) models of the grey system theory were discussed for their feasibilities of modding for batch dyeing process. The combination of direct dyestuff Fast Red F3B on cotton was chosen as a representative of the common dyeing method for describing the modeling process. Firstly, the GM( 1, 1 ) model and the GM(1, 1) combined with GM(0, N) model were employed to model the equilibrium percentage of dyeing uptake rate. Secondly, an integrated dyeing uptake rate model with three factors ( temperature, salt concentration, and pH) was established based on the adsorption rate equation. Experimental results show that this model has higher accuracy and beetler generalization ability, which can predict the results of batch dyeing process. Due to the application of grey system theory, the model has a lot of advantages, such as being easy to determine the parameter value and small amount of calculation. So it can also be suitable for the same type of combination of dyestuff-fahric by changing the parameters value only. 展开更多
关键词 grey model adsorption rate equation integrated modeling dyeing uptake rate
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Evolution of deformation property and strength component mobilization for thermally treated Beishan granite under compression 被引量:4
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作者 CHEN Shi-wan LIANG Feng +1 位作者 ZUO Shuang-ying WU Dao-yong 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第1期219-234,共16页
The cohesion weakening and friction strengthening(CWFS)model for rock reveals the strength components mobilization process during progressive brittle failure process of rock,which is very helpful in understanding mech... The cohesion weakening and friction strengthening(CWFS)model for rock reveals the strength components mobilization process during progressive brittle failure process of rock,which is very helpful in understanding mechanical properties of rock.However,the used incremental cyclic loading−unloading compression test for the determination of strength components is very complicated,which limits the application of CWFS model.In this paper,incremental cyclic loading−unloading compression test was firstly carried out to study the evolution of deformation and the strength properties of Beishan granite after various temperatures treated under different confining pressures.We found the axial and lateral unloading modulus are closely related to the applied stress and damage state of rock.Based on these findings,we can accurately determine the plastic strain during the entire failure process using conventional tri-axial compression test data.Furthermore,a strength component(cohesive and frictional strength)determination method was developed using conventional triaxial compression test.Using this method,we analyzed the variation of strength mobilization and deformation properties of Beishan granite after various temperatures treated.At last,a non-simultaneous strength mobilization model for thermally treated granite was obtained and verified by numerical simulation,which demonstrated the effectiveness of the proposed strength determination method. 展开更多
关键词 strength components mobilization secant unloading modulus Beishan granite thermally treated post-failure
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Flower solid modeling based on sketches 被引量:3
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作者 Zhan DING Shu-chang XU +2 位作者 Xiu-zi YE Yin ZHANG San-yuan ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第4期481-488,共8页
In this paper we propose a method to model flowers of solid shape. Based on (Ijiri et al., 2005)’s method, we separate individual flower modeling and inflorescence modeling procedures into structure and geometry mode... In this paper we propose a method to model flowers of solid shape. Based on (Ijiri et al., 2005)’s method, we separate individual flower modeling and inflorescence modeling procedures into structure and geometry modeling. We incorporate interactive editing gestures to allow the user to edit structure parameters freely onto structure diagram. Furthermore, we use free-hand sketching techniques to allow users to create and edit 3D geometrical elements freely and easily. The final step is to automatically merge all independent 3D geometrical elements into a single waterproof mesh. Our experiments show that this solid modeling approach is promising. Using our approach, novice users can create vivid flower models easily and freely. The generated flower model is waterproof. It can have applications in visualization, animation, gaming, and toys and decorations if printed out on 3D rapid prototyping devices. 展开更多
关键词 Solid modeling Floral diagram INFLORESCENCE GESTURE Constrained Delauny triangulation (CDT) Freehand sketching
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Implications of tree species–environment relationships for the responsiveness of Himalayan krummholz treelines to climate change 被引量:3
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作者 Niels SCHWAB Udo SCHICKHOFF +5 位作者 Birgit BURZLE Michael MULLER Jurgen BOHNER Ram Prasad CHAUDHARY Thomas SCHOLTEN Jens OLDELAND 《Journal of Mountain Science》 SCIE CSCD 2017年第3期453-473,共21页
Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. ... Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths (3700-4200 m) at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions (e.g., nutrient and thermal deficits, plant interactions) across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran's eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming. 展开更多
关键词 HIMALAYA Nepal Population structure Rhododendron campanulatum Spatial patterns Species-environment relationships Stand density Variation partitioning
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Assessment of different genetic distances in constructing cotton core subset by genotypic values 被引量:7
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作者 Jian-cheng WANG Jin HU +1 位作者 Xin-xian HUANG Sheng-chun XU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第5期356-362,共7页
One hundred and sixty-eight genotypes of cotton from the same growing region were used as a germplasm group to study the validity of different genetic distances in constructing cotton core subset. Mixed linear model a... One hundred and sixty-eight genotypes of cotton from the same growing region were used as a germplasm group to study the validity of different genetic distances in constructing cotton core subset. Mixed linear model approach was employed to unbiasedly predict genotypic values of 20 traits for eliminating the environmental effect. Six commonly used genetic distances(Euclidean,standardized Euclidean,Mahalanobis,city block,cosine and correlation distances) combining four commonly used hierarchical cluster methods(single distance,complete distance,unweighted pair-group average and Ward's methods) were used in the least distance stepwise sampling(LDSS) method for constructing different core subsets. The analyses of variance(ANOVA) of different evaluating parameters showed that the validities of cosine and correlation distances were inferior to those of Euclidean,standardized Euclidean,Mahalanobis and city block distances. Standardized Euclidean distance was slightly more effective than Euclidean,Mahalanobis and city block distances. The principal analysis validated standardized Euclidean distance in the course of constructing practical core subsets. The covariance matrix of accessions might be ill-conditioned when Mahalanobis distance was used to calculate genetic distance at low sampling percentages,which led to bias in small-sized core subset construction. The standardized Euclidean distance is recommended in core subset construction with LDSS method. 展开更多
关键词 Core subset Mixed linear model Least distance stepwise sampling (LDSS) method Standardized Euclidean distance Mahalanobis distance
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Experiments of Brittle-Plastic Transition and Instability Modes of Juyongguan Granite at Different Temperatures and Pressures 被引量:3
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作者 Zhou Yongsheng, Jiang Haikun and He ChangrongInstitute of Geology, Open Tectonophysics Laboratory, CSB, Beijing 100029, China 《Earthquake Research in China》 2003年第2期169-182,共14页
Three groups of experiments on brittle-plastic transition and instability modes of granite were performed in a triaxial vessel with solid pressure medium at high temperature and high pressure. The results of experimen... Three groups of experiments on brittle-plastic transition and instability modes of granite were performed in a triaxial vessel with solid pressure medium at high temperature and high pressure. The results of experiments show that brittle faulting is the major failure mode at temperature <300℃, but crystal-plastic deformation is dominate at temperature >800℃, and there is a transition with increasing temperature from semi-brittle faulting to cataclastic flow and semi-brittle flow at temperatures of 300~800℃. So, temperature is the most influential factor in brittle-plastic transition of granite and confining pressure is the second factor. The results also show that progressive failure of granite occurs at lower pressure or high temperature where there is crystal plasticity, and sudden instability occurs at room temperature and high pressure (>300MPa) or high temperature and great pressure(550℃600MPa ~650℃700MPa), and a broad regime of quasi-sudden instability exists between the T-P condition of progressive failure and sudden instability. So, instability modes of granite depend simultaneously on the pressure and temperature. 展开更多
关键词 Deformation and failure Instability modes Brittle-plastic transition High temperature and great pressure GRANITE
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Computational Simulation of Complex Structure Fancy Yarns
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作者 马建伟 周奉磊 +1 位作者 陈韶娟 许文娜 《Journal of Donghua University(English Edition)》 EI CAS 2007年第2期244-247,共4页
A study is reported for mathematical model and simulative of complex structure fancy yams. The investigated complex structure fancy yams have a multithread structure composed of three components core, effect, and bind... A study is reported for mathematical model and simulative of complex structure fancy yams. The investigated complex structure fancy yams have a multithread structure composed of three components core, effect, and binder yams. In current research the precondition was accepted that the cross-sections of the both two yams of the effect intermediate product in the complex structure fancy yam remain the circles shaped, and this shape does not change during manufacturing of the fancy yam. Mathematical model of complex structure fancy yarn is established based on parameter equation of space helix line and computer simulative is further carried out using the computational mathematical tool Matlab 6.5. Theoretical structure of fancy yam is compared with an experimental sample. The simulative system would help for further the set of informative in designing of new assortment of the complex structure fancy yarns and prediction of visual effects of fancy yams in end-use fabrics. 展开更多
关键词 fancy yarn mathematical model space helix computer simulation
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Development and Validation of National Cotton Cultivar Registration Index Model in Yangtze River Valley 被引量:1
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作者 Naiyin XU Jian LI 《Agricultural Science & Technology》 CAS 2014年第9期1530-1533,1537,共5页
[Objective] Based on the cotton variety high yielding potential, fiber quality traits, disease resistance, and early maturity characters, a cultivar registration index model was developed to simplify the tedious calcu... [Objective] Based on the cotton variety high yielding potential, fiber quality traits, disease resistance, and early maturity characters, a cultivar registration index model was developed to simplify the tedious calculation process in national cotton registration procedure, and thus to enhance the practical application of cultivar regis- tration index in cotton breeding ancl cotton recommending. [Method] By means of correlation analysis, partial correlation analysis and path analysis methods, the cor- relation of cotton main properties and their effects on cultivar registration index were explored using the dataset of national cotton regional trials in Yangtze River Valley during 1996-2013. The cultivar registration index model was constructed with step- wise regression statistical technique to ascertain the quantitative relationship of main characters with cultivar registration index, and the regional cotton trial dataset in 2013 was used to validate the model. [Result] Several characters with larger deter- minants to cultivar registration index were screened out,ie. lint yield increase ratio, pro-frost yield ratio, verticillium wilt index, fiber strength, fusarium wilt index and mi- cronaire value. The cultivar registration index model defined the functional relation- ship of cultivar registration index with the selected main characters, among which lint yield increase ratio, fiber strength and micronaire value contributed most to culti- var registration index. The model validation with regional cotton trials in 2013 indi- cated the root mean square error, RMSE was only 2.77, and the variation coeffi- cient was 6.77%, which confirmed the model prediction effect was quite perfect. [Conclusion] The developed cultivar registration index model was reliable enough to simulate the complicated scoring system in cultivar registration procedure, also sim- plified cotton registration process, and enhanced the practicability of the cultivar reg- istration index. 展开更多
关键词 Cotton (Gossypium hirsutum L.) Cultivar registration index Model de- velopment Yangtze River Valley Regional crop trials
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Assessment of Point and Nonpoint Sources Pollution in Songhua River Basin,Northeast China by Using Revised Water Quality Model 被引量:14
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作者 YANG Yuhong YAN Baixing SHEN Wanbin 《Chinese Geographical Science》 SCIE CSCD 2010年第1期30-36,共7页
Individual participation of pollutants in the pollution load should be estimated even if roughly for the appropriate environmental management of a river basin.It is difficult to identify the sources and to quantify th... Individual participation of pollutants in the pollution load should be estimated even if roughly for the appropriate environmental management of a river basin.It is difficult to identify the sources and to quantify the load, especially in modeling nonpoint source.In this study a revised model was established by integrating point and nonpoint sources into one-dimensional Streeter-Phelps(S-P) model on the basis of real-time hydrologic data and surface water quality monitoring data in the Jilin Reach of the Songhua River Basin.Chemical oxygen demand(COD) and ammonia nitrogen(NH 3-N) loads were estimated.Results showed that COD loads of point source and nonpoint source were 134 958 t/yr and 86 209 t/yr, accounting for 61.02% and 38.98% of total loads, respectively.NH 3-N loads of point source and nonpoint source were 16 739 t/yr and 14 272 t/yr, accounting for 53.98% and 46.02%, respectively.Point source pollution was stronger than nonpoint source pollution in the study area at present.The water quality of upstream was better than that of downstream of the rivers and cities.It is indispensable to treat industrial wastewater and municipal sewage out of point sources, to adopt the best management practices to control diffuse pollutants from agricultural land and urban surface runoff in improving water quality of the Songhua River Basin.The revised S-P model can be successfully used to identify pollution source and quantify point source and nonpoint source loads by calibrating and validating. 展开更多
关键词 ammonia nitrogen chemical oxygen demand nonpoint source pollution point source pollution revised water quality model Songhua River Basin
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