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Crystallization management of CsPbI_(2)Br perovskites by PbAc_(2)-incorporated twice spin-coating process for efficient and stable CsPbI_(2)Br perovskite solar cells
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作者 Yu Liu Kun Lang +6 位作者 Huifang Han Huijing Liu Yao Fu Pengchen Zou Yinhui Lyu Jia Xu Jianxi Yao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期419-428,I0008,共11页
CsPbI_(2)Br perovskite solar cell has been extensively studied due to its exceptional thermal stability and relatively stable perovskite phase structure.However,the presence of bromine leads to a rapid crystallization... CsPbI_(2)Br perovskite solar cell has been extensively studied due to its exceptional thermal stability and relatively stable perovskite phase structure.However,the presence of bromine leads to a rapid crystallization rate of CsPbI_(2)Br films,resulting in small grain size and high defect density.Additionally,CsPbI_(2)Br demonstrates poor light absorption due to its wide bandgap.Therefore,it is crucial to control the crystallization rate and increase the film thickness to reduce defect density,enhance light absorption,and improve photovoltaic performance.In this study,we utilized a PbAc_(2)-incorporated twice spincoating(PTS) process to address these issues.Initially,PbAc_(2) was added to the CsPbI_(2)Br precursor solution to form a CsPbI_(2)Br film,which was then coated with the CsPbI_(2)Br precursor solution to produce the PTS film,Ac^(-)can delay the perovskite crystallization,leading to the formation of thicker and denser CsPbI_(2)Br films.Moreover,lone-pair electrons of the oxygen atom provided by Ac^(-)formed coordination bonds with under-coordinated Pb~(2+) ions to fill halogen ion vacancies,thereby reducing the defect density.Ultimately,the PTS CsPbI_(2)Br device achieved a peak power conversion efficiency(PCE) of 16.19% and maintained 96.7% of its initial PCE over 1500 h at room temperature under 25% relative humidity without any encapsulation. 展开更多
关键词 CsPbI_(2)Br twice spin-coating process PbAc_(2) Crystallization management Perovskite solar cells
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Obtainment of Transgenic Tobacco Harboring phbA , phbB and phbC Genes by Twice Transformation 被引量:4
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作者 张景昱 叶梁 +1 位作者 李丽 宋艳茹 《Acta Botanica Sinica》 CSCD 2001年第1期59-62,共4页
To avoid the long time required for conventional sexual crossing, transgenic tobacco (Nicotiana tabacum L.) plants harboring phbA gene (encoding 3_ketothiolase) were used as the target plant for the second transfo... To avoid the long time required for conventional sexual crossing, transgenic tobacco (Nicotiana tabacum L.) plants harboring phbA gene (encoding 3_ketothiolase) were used as the target plant for the second transformation mediated by Agrobacterium tumefaciens (Smith et Townsend) Conn LBA4404 containing pZCB which was constructed by linking phbB (encoding acetoacetyl_CoA reductase), phbC (encoding PHB synthase) and ctp sequence to pBIB_HYG under the control of CaMV 35S promoter. The hygromycin resistant transformants were morphologically normal and stable integration of phbB and phbC was confirmed by PCR and PCR_Southern. Moreover, RT_PCR_DNA hybridization analysis showed that 6.67% of the transformed tobacco plants could express both phbB and phbC at transcriptional level. 展开更多
关键词 poly (3_hydroxybutyrate) (PHB) twice transformation transgenic tobacco
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相对化One-Way函数的存在性
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作者 曹子宁 吕义忠 石纯一 《软件学报》 EI CSCD 北大核心 2001年第6期884-888,共5页
One- Way函数在计算复杂性和密码技术中均有重要的应用 .将 Grollmann和 Selman的结果推广到相对化和非一致复杂类的情形 ,证明了复杂类 UP/ poly,UP,P/ poly等之间的包含关系与强相对化 one- way函数、弱相对化 one-
关键词 计算复杂性 one-way函数 相对化 计算机
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A new group key management scheme based on keys tree, XOR operation and one-way function 被引量:1
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作者 张勇 张翼 汪为农 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期54-58,共5页
By introducing XOR operation and one-way function chains to group key management schemes based on the keys tree, a new group key management scheme based on the keys tree, XOR operation and one-way function chains is p... By introducing XOR operation and one-way function chains to group key management schemes based on the keys tree, a new group key management scheme based on the keys tree, XOR operation and one-way function chains is proposed. Initialization, member adding and member evicting operations are introduced. The new scheme is compared with three other group key management schemes which are based on the keys tree: SKDC, LKH, and OFF. As far as transmission, computation and storage costs are concerned, the performance of the new group key management scheme is the best. The security problem of the new scheme is analyzed. This new scheme provides backward and forward security, i.e.. newly admitted group members cannot read previous multicast messages and evicted members cannot read future multicast messages, even with collusion by many arbitrarily evicted members. 展开更多
关键词 secure group communication group key management keys tree one-way function
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Accuracy analysis of the optimal separable approximation method of one-way wave migration
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作者 杜淑媛 陈景波 刘洪 《Applied Geophysics》 SCIE CSCD 2011年第4期328-336,371,372,共11页
An approximation for the one-way wave operator takes the form of separated space and wave-number variables and makes it possible to use the FFT, which results in a great improvement in the computational efficiency. Fr... An approximation for the one-way wave operator takes the form of separated space and wave-number variables and makes it possible to use the FFT, which results in a great improvement in the computational efficiency. From the function approximation perspective, the OSA method shares the same separable approximation format to the one-way wave operator as other separable approximation methods but it is the only global function approximation among these methods. This leads to a difference in the phase error curve, impulse response, and migration result from other separable approximation methods. The difference is that the OSA method has higher accuracy, and the sensitivity to the velocity variation declines with increasing order. 展开更多
关键词 one-way wave operator MIGRATION separable approximation optimal separable approximation
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One-way wave equation seismic prestack forward modeling with irregular surfaces 被引量:9
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作者 Xiong Xiaojun He Zhenhua Huang Deji 《Applied Geophysics》 SCIE CSCD 2006年第1期13-17,共5页
Mathematical geophone (MG) and equal-time stacking (ETS) principles are used to implement seismic prestack forward modeling with irregular surfaces using the oneway acoustic wave-equation. This method receives sei... Mathematical geophone (MG) and equal-time stacking (ETS) principles are used to implement seismic prestack forward modeling with irregular surfaces using the oneway acoustic wave-equation. This method receives seismic primary reflections from the subsurface using a set of virtual MGs. The receivers can be located anywhere on an irregular observing surface. Moreover, the ETS method utilizes the one-way acoustic wave equation to easily and quickly image and extrapolate seismic reflection data. The method is illustrated using high single-noise ratio common shot gathers computed by numerical forward modeling of two simple models, one with a flat surface and one with an irregular surface, and a complex normal fault model. A prestack depth migration method for irregular surface topography was used to reoroduce the normal fault model with high accuracy. 展开更多
关键词 mathematical geophone equal-time stacking principle seismic prestack forward modeling irregular surfaces and one-way wave-equation.
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Design and analysis of logarithmic spiral type sprag one-way clutch 被引量:7
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作者 刘志辉 严宏志 曹煜明 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4597-4607,共11页
A complete mathematical model for logarithmic spiral type sprag one-way clutch design and analysis is given.It assumes that the motion of all clutch components can be expressed by a model of epicyclic gearing.It takes... A complete mathematical model for logarithmic spiral type sprag one-way clutch design and analysis is given.It assumes that the motion of all clutch components can be expressed by a model of epicyclic gearing.It takes advantage of Hunt-Crossley contact impact theory to calculate the contact forces between sprags and races,and it can be used for optimization of design and comparison with other types of sprag clutches.A good deal of analysis shows that the parameters of the steady windup angle,the steady contact force,the natural frequency and natural cycle of clutch have nothing to do with the initial velocity of outer race,while the parameters of the maximum transient windup angle,the maximum transient impact force and the steady engagement time increase linearly in the mode of engaging operation of clutch.It is also shown that the strut angle has great influence on the dynamic engagement performance of clutch.The parameters of the steady windup angle,the maximum transient windup angle,the steady engaging time,the steady contact force,the maximum transient impact force and the natural cycle of clutch decrease linearly nearly with the inner strut angle,while the natural frequency of the system increases linearly with the inner strut angle. 展开更多
关键词 mathematical model logarithmic spiral one-way clutch hunt-crossley windup angle steady contact force transient impact force
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Pressure-impulse diagram with multiple failure modes of one-way reinforced concrete slab under blast loading using SDOF method 被引量:9
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作者 汪维 张舵 +2 位作者 卢芳云 汤福静 王松川 《Journal of Central South University》 SCIE EI CAS 2013年第2期510-519,共10页
Two loosely coupled single degree of freedom (SDOF) systems were used to model the flexural and direct shear responses of one-way reinforced concrete slabs subjected to explosive loading. Blast test results show that ... Two loosely coupled single degree of freedom (SDOF) systems were used to model the flexural and direct shear responses of one-way reinforced concrete slabs subjected to explosive loading. Blast test results show that the SDOF systems are accurate in predicting the failure mode of the slab under blast loads by incorporating the effects of the strain rate effect caused by rapid load application. Based on different damage criteria, pressure-impulse (P-I) diagrams of the two failure modes were analyzed with the SDOF systems. The effects of span length, concrete strength, and reinforcement ratio of the slab on the P-I diagram were also investigated. Results indicate that a slab tends to fail in direct shear mode when it is of a smaller span length and tends to fail in flexure mode when it is of a larger span length. With the increase of the concrete strength or reinforced ratio, both the flexure and shear capacity increase. Based on numerical results, a simplified method and a semi analytical equation for deriving the P-I diagram are proposed for different failure modes and damage levels. 展开更多
关键词 blast load failure mode pressure impulse diagram one-way reinforced concrete slab single degree of freedom
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Additive Benefits of Twice Forest Bathing Trips in Elderly Patients with Chronic Heart Failure 被引量:18
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作者 MAO Gen Xiang CAO Yong Bao +8 位作者 YANG Yan CHEN Zhuo Mei DONG Jian Hua CHEN Sha Sha WU Qing LYU Xiao Ling JIA Bing Bing YAN Jing WANG Guo Fu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第2期159-162,共4页
Chronic heart failure (CHF), a clinical syndrome resulting from the consequences of various cardiovascular diseases (CVDs), is increasingly becoming a global cause of morbidity and mortality. We had earlier demons... Chronic heart failure (CHF), a clinical syndrome resulting from the consequences of various cardiovascular diseases (CVDs), is increasingly becoming a global cause of morbidity and mortality. We had earlier demonstrated that a 4-day forest bathing trip can provide an adjunctive therapeutic influence on patients with CHF. To further investigate the duration of the impact and the optimal frequency of forest bathing trips in patients with CHF, we recruited those subjects who had experienced the first forest bathing trip again after 4 weeks and randomly categorized them into two groups, namely, the urban control group (city) and the forest bathing group (forest). After a second 4-day forest bathing trip, we observed a steady decline in the brain natriuretic peptide levels, a biomarker of heart failure, and an attenuated inflammatory response as well as oxidative stress. Thus, this exploratory study demonstrated the additive benefits of twice forest bathing trips in elderly patients with CHF, which could further pave the way for analyzing the effects of such interventions in CVDs. 展开更多
关键词 CHF Additive Benefits of twice Forest Bathing Trips in Elderly Patients with Chronic Heart Failure BNP
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Application of direct computing of one-way coupling technique in seismic analysis of concrete gravity dam 被引量:4
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作者 Quoc Cong TRINH 《Water Science and Engineering》 EI CAS 2010年第1期95-101,共7页
A dam-reservoir system subjected to an earthquake is a nonlinear system, because the fluid equations are always nonlinear regardless of the linear or nonlinear model used for the dam body. Therefore, transient analysi... A dam-reservoir system subjected to an earthquake is a nonlinear system, because the fluid equations are always nonlinear regardless of the linear or nonlinear model used for the dam body. Therefore, transient analysis is necessary. In this study, dam-reservoir interaction during earthquake excitation was modeled by utilizing coupled finite element equations based on the Eulerian approach. Direct computing of the one-way coupling technique was used to solve the coupled equations. This technique is based on a simple assumption that the fluid hydrodynamic pressure is applied to the dam body while the deformation of the dam has no influence on the water field. Seismic response analysis of the Sonla concrete gravity dam constructed in Sonla Province, Vietnam was carried out as a verification example. The results of the methodology introduced are in close agreement with results of the iterative method and the solution procedure is found to be less time-consuming than that of the iterative method. This method is very convenient and can be easily implemented in finite element programs with fluid-structure interaction modules. 展开更多
关键词 dam-reservoir interaction time domain one-way coupling Sonla Dam
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A parametric bootstrap approach for one-way classification model with skew-normal random effects 被引量:3
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作者 YE Ren-dao XU Li-jun +1 位作者 LUO Kun JIANG Ling 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2019年第4期423-435,共13页
In this paper,several properties of one-way classification model with skew-normal random effects are obtained,such as moment generating function,density function and noncentral skew chi-square distribution,etc.Based o... In this paper,several properties of one-way classification model with skew-normal random effects are obtained,such as moment generating function,density function and noncentral skew chi-square distribution,etc.Based on the EM algorithm,we discuss the maximum likelihood(ML)estimation of unknown parameters.For testing problem of fixed effect,a parametric bootstrap(PB)approach is developed.Finally,some simulation results on the Type I error rates and powers of the PB approach are obtained,which show that the PB approach provides satisfactory performances on the Type I error rates and powers,even for small samples.For illustration,our main results are applied to a real data problem. 展开更多
关键词 PARAMETRIC BOOTSTRAP EM algorithm one-way classification model SKEW-NORMAL DISTRIBUTION SKEW CHI-SQUARE DISTRIBUTION
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Application of simple array method in one-way traffic synthetic asessment 被引量:2
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作者 裴玉龙 刘广萍 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第1期1-5,共5页
One-Way Traffic synthetic assessing can not only determine the assessment method, but can also provide an opportunity for further study of road systems. Comparing three Road Traffic Planning methods, which are Value A... One-Way Traffic synthetic assessing can not only determine the assessment method, but can also provide an opportunity for further study of road systems. Comparing three Road Traffic Planning methods, which are Value Analysis method, Simple Array method and Step Analysis method, this paper concludes that Simple Array method has one prominent merit, avoiding the complicated relationship of various factors and simplifying the complex problem. Therefore Simple Array method is firstly presented in this paper to be the assessing measure to assess the One-Way Traffic Planning project. Although this assessing method cannot wholly give way to man’s will, through consistently testing on qualitative factors and with the decision-making results of a multi-program, this method is still an effective method. Using an example of Harbin One-Way Traffic planning, with seven assessing indexes including economic benefit index, Simple Array method is applied to synthetically assessing the program. This fully reflects the general function of One-Way Traffic planning program and objectively evaluates the program. It also proves that, as the method of One-Way Traffic synthetic assessing, Simple Array method is rational and practical. 展开更多
关键词 simple array method one-way traffic PROGRAM synthetic assessment
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Urban One-way Traffic Organization and Its Evaluation 被引量:2
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作者 裴玉龙 伊新苗 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第2期121-124,共4页
One-way traffic organization is a direct, efficient and economic method to solve traffic congestion and expand traffie capacity. With its evolution, advantages and disadvantages introduced its setting conditions demon... One-way traffic organization is a direct, efficient and economic method to solve traffic congestion and expand traffie capacity. With its evolution, advantages and disadvantages introduced its setting conditions demonstrated. The general method and processes are summarized in planning for urban one-way streets project, viz. investigation, drawing out and evaluation of project, selecting of project and beneficial analysis. Fuzzy synthetical evaluation other fields is employed to evaluate the project. Its evaluation system and method is introduced and Delphi method is adopted to obtain evaluation index. Finally, taking Harbin city as an example, the application process of above-mentioned method is illuminated. Accordingly, it is proved that the method is exercisable. 展开更多
关键词 one-way traffic organization traffic congestion traffic capacity
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ONE-WAY MULTIVARIATE REPEATED MEASUREMENTS ANALYSIS OF VARIANCE MODEL 被引量:2
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作者 Abdul-Hussein Saber AL-MOUEL 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第4期435-448,共14页
The one-way multivariate repeated measurements analysis of variance (1-way MRM ANOVA) model for complete data and the sphericity test are studied.
关键词 one-way multivariate repeated measurements analysis of variance likelihood ratio criterion sphericity test asymptotic expansion.
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One-way hash function based on hyper-chaotic cellular neural network 被引量:1
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作者 杨群亭 高铁杠 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第7期2388-2393,共6页
The design of an efficient one-way hash function with good performance is a hot spot in modern cryptography researches. In this paper, a hash function construction method based on cell neural network with hyper-chaos ... The design of an efficient one-way hash function with good performance is a hot spot in modern cryptography researches. In this paper, a hash function construction method based on cell neural network with hyper-chaos characteristics is proposed. First, the chaos sequence is gotten by iterating cellular neural network with Runge Kutta algorithm, and then the chaos sequence is iterated with the message. The hash code is obtained through the corre- sponding transform of the latter chaos sequence. Simulation and analysis demonstrate that the new method has the merit of convenience, high sensitivity to initial values, good hash performance, especially the strong stability. 展开更多
关键词 one-way hash function HYPER-CHAOS cellular neural network Runge Kutta formula
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On Unobservability of One-Way Speed of Light 被引量:1
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作者 Yuan Zhong ZHANG (Institute of Theoretical Physics, Academia Sinica, P. O. Box 2735, Beijing 100080, China.) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第4期253-264,共12页
In this paper we recall the different definitions of simultaneity, the coordinate time interval and the velocity. It is emphasized that the above second two definitions depend on the simultaneity. We review the test t... In this paper we recall the different definitions of simultaneity, the coordinate time interval and the velocity. It is emphasized that the above second two definitions depend on the simultaneity. We review the test theories on special relativity. It is shown that anisotropy (if possible) of one-way speed of light has not any ef- fects in the physical experiments. Therefore anisotropy of one-way speed of light cannot be determined by the experiments, except if an absolute (standard) simultaneity would be found. 展开更多
关键词 SIMULTANEITY one-way speed of light Test theory Special relativity
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Autonomous optical navigation of Mars probe aided by one-way Doppler measurements in capture stage 被引量:1
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作者 ZHANG Zhibin JI Haibo YANG Jie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第3期602-611,共10页
The optical navigation errors of Mars probe in the capture stage depend closely on which targets are selected to be observed in the Mars system.As for this problem,an integrated navigation scheme is proposed wherein t... The optical navigation errors of Mars probe in the capture stage depend closely on which targets are selected to be observed in the Mars system.As for this problem,an integrated navigation scheme is proposed wherein the optical observation is aided by one-way Doppler measurements.The errors are then analyzed respectively for the optical observation and one-way Doppler measurements.The real-time calculating scheme which exploits the extended Kalman filter(EKF)framework is designed for the integrated navigation.The simulation tests demonstrate that the errors of optical navigation,which select the Mars moon as the observation target,are relatively smaller than those in the Mars-orientation optical navigation case.On one hand,the integrated navigation errors do not depend on the selecting pattern of optical observation targets.On the other hand,the integrated navigation errors are significantly reduced as compared with those in the optical-alone autonomous navigation mode. 展开更多
关键词 Mars probe autonomous navigation one-way Doppler measurement optical observation capture stage
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The Normal Meromorphic Functions Family Concerning Higher Order Derivative and Shared Set by One-Way 被引量:1
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作者 Yi Li 《Advances in Pure Mathematics》 2011年第6期322-324,共3页
Let F be a meromorphic functions family on the unit disc Δ, If for every (the zeros of f is a multiplicity of at least k) and if then and ( ), then F is normal on Δ.
关键词 MEROMORPHIC Function NORMALITY Criterion SHARED Set by one-way Higher Order DERIVATIVE
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A novel twice-interpolation finite element method for solid mechanics problems 被引量:3
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作者 C. Zheng S. C. Wu +1 位作者 X. H. Tang J. H. Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第2期265-278,共14页
Formulation and numerical evaluation of a novel twice-interpolation finite element method (TFEM) is presented for solid mechanics problems. In this method, the trial function for Galerkin weak form is constructed th... Formulation and numerical evaluation of a novel twice-interpolation finite element method (TFEM) is presented for solid mechanics problems. In this method, the trial function for Galerkin weak form is constructed through two stages of consecutive interpolation. The primary interpolation follows exactly the same procedure of standard FEM and is further reproduced according to both nodal values and averaged nodal gradients obtained from primary interpolation. The trial functions thus constructed have continuous nodal gradients and contain higher order polynomial without increasing total freedoms. Several benchmark examples and a real dam problem are used to examine the TFEM in terms of accuracy and convergence. Compared with standard FEM, TFEM can achieve significantly better accuracy and higher convergence rate, and the continuous nodal stress can be obtained without any smoothing operation. It is also found that TFEM is insensitive to the quality of the elemental mesh. In addition, the present TFEM can treat the incompressible material without any modification. 展开更多
关键词 twice-interpolation finite element method·Stress smoothing Volumetric locking Mesh distortion
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Analysis on Chinese Regional Differences in International Tourism Foreign Exchange Earnings with Method of One-way Variance Analysis 被引量:1
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作者 Zhang Liuchen 《新丝路(下旬)》 2016年第20期58-61,共4页
Based on data over 31 provinces and cities in China from2006 to 2013,this thesis first divides those 31 provinces and cities into four economic regions including northeastern region,central region,eastern region and w... Based on data over 31 provinces and cities in China from2006 to 2013,this thesis first divides those 31 provinces and cities into four economic regions including northeastern region,central region,eastern region and western region.Based on data over 31 provinces and cities in China from 2006 to 2013,those 31 provinces and cities were devided into four economic regions in this thesis,including northeastern region,central region,eastern region and western region.Then,it takes international tourism foreign exchange earnings as the dependent variable,the four economic regions as the factor to measure the difference of international tourism foreign exchange earnings in different regions,and finds out the main reasons of it.Through the one-way variance analysis on international tourism foreign exchange earnings,we can know that international tourism foreign exchange earnings have differences in different regions apparently.Besides,significant differences can be found between northeastern and central regions as well as eastern and western regions,while it is not the same case between the central and western regions. 展开更多
关键词 international tourism foreign exchange earnings one-way variance analysis regional differences
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