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Estimation of Daily Global Solar Radiation with Different Sunshine-Based Models for Some Burundian Stations
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作者 Mathias Bashahu Gratien Ndacayisaba 《Energy and Power Engineering》 2024年第1期1-20,共20页
Sunshine duration (S) based empirical equations have been employed in this study to estimate the daily global solar radiation on a horizontal surface (G) for six meteorological stations in Burundi. Those equations inc... Sunshine duration (S) based empirical equations have been employed in this study to estimate the daily global solar radiation on a horizontal surface (G) for six meteorological stations in Burundi. Those equations include the Ångström-Prescott linear model and four amongst its derivatives, i.e. logarithmic, exponential, power and quadratic functions. Monthly mean values of daily global solar radiation and sunshine duration data for a period of 20 to 23 years, from the Geographical Institute of Burundi (IGEBU), have been used. For any of the six stations, ten single or double linear regressions have been developed from the above-said five functions, to relate in terms of monthly mean values, the daily clearness index () to each of the next two kinds of relative sunshine duration (RSD): and . In those ratios, G<sub>0</sub>, S<sub>0 </sub>and stand for the extraterrestrial daily solar radiation on a horizontal surface, the day length and the modified day length taking into account the natural site’s horizon, respectively. According to the calculated mean values of the clearness index and the RSD, each station experiences a high number of fairly clear (or partially cloudy) days. Estimated values of the dependent variable (y) in each developed linear regression, have been compared to measured values in terms of the coefficients of correlation (R) and of determination (R<sub>2</sub>), the mean bias error (MBE), the root mean square error (RMSE) and the t-statistics. Mean values of these statistical indicators have been used to rank, according to decreasing performance level, firstly the ten developed equations per station on account of the overall six stations, secondly the six stations on account of the overall ten equations. Nevertheless, the obtained values of those indicators lay in the next ranges for all the developed sixty equations:;;;, with . These results lead to assert that any of the sixty developed linear regressions (and thus equations in terms of and ), fits very adequately measured data, and should be used to estimate monthly average daily global solar radiation with sunshine duration for the relevant station. It is also found that using as RSD, is slightly more advantageous than using for estimating the monthly average daily clearness index, . Moreover, values of statistical indicators of this study match adequately data from other works on the same kinds of empirical equations. 展开更多
关键词 Clearness Index Two kinds of Relative Sunshine Duration Ångström-Prescott Linear Model and Four Derivatives Statistical Tests Six Burundian Stations
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Convergence Phenomenon with Fourier Series of tg(x2)and Alike
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2024年第7期556-595,共40页
The Fourier series of the 2π-periodic functions tg(x2)and 1sin(x)and some of their relatives (first of their integrals) are investigated and illustrated with respect to their convergence. These functions are Generali... The Fourier series of the 2π-periodic functions tg(x2)and 1sin(x)and some of their relatives (first of their integrals) are investigated and illustrated with respect to their convergence. These functions are Generalized functions and the convergence is weak convergence in the sense of the convergence of continuous linear functionals defining them. The figures show that the approximations of the Fourier series possess oscillations around the function which they represent in a broad band embedding them. This is some analogue to the Gibbs phenomenon. A modification of Fourier series by expansion in powers cosn(x)for the symmetric part of functions and sin(x)cosn−1(x)for the antisymmetric part (analogous to Taylor series) is discussed and illustrated by examples. The Fourier series and their convergence behavior are illustrated also for some 2π-periodic delta-function-like sequences connected with the Poisson theorem showing non-vanishing oscillations around the singularities similar to the Gibbs phenomenon in the neighborhood of discontinuities of functions. . 展开更多
关键词 Gibbs Phenomenon Generalized Functions Weak Convergence Chebyshev Polynomials of First and Second Kind Even and Odd Generating Functions for Chebyshev Polynomials POLYLOGARITHMS Completeness Relations
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Three Kinds of Films Obtained from Plasma Poly-merization of Octamethylcyclotetrasioxane
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作者 刘益民 张广秋 葛袁静 《Plasma Science and Technology》 SCIE EI CAS CSCD 2002年第2期1253-1259,共7页
Three kinds of 'films' i.e. cross-linked film, grainy film and transparent film, wereobtained in the process of plasma polymerization of Octamethylcyclotetrasioxane(D4) under dif-ferent conditions. From SEM ph... Three kinds of 'films' i.e. cross-linked film, grainy film and transparent film, wereobtained in the process of plasma polymerization of Octamethylcyclotetrasioxane(D4) under dif-ferent conditions. From SEM photos, we can see that the cross-linked film has a network form.From XPS spectra, we can see that the content of Si-C bond of the cross-linked film is lower thanthat of the transparent film, and this result agrees well with the test results of FTIR spectra. Thisproves that the c1eavage of the Si-C bond and C-H bond are the main cleavage in the formationof cross-linked film, whereas the cleavage of the Si-O is the main cleavage in the formation oftransparent film. In order to enhance the collision of the reactive particles and investigate theinfluence of magnetic field on the plasma polymerization, we introduced the magnetic field, as aresult, we got the grainy film. 展开更多
关键词 three kinds of Films Obtained from Plasma Poly-merization of Octamethylcyclotetrasioxane SIO
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The Certification Labels of Alcoholic Drinks Products Will Be Classified into Three Kinds
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《China Standardization》 2006年第2期3-,共1页
关键词 HACCP The Certification Labels of Alcoholic Drinks Products Will Be Classified into three kinds BE
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Comparison of three kinds of treatment for pediatric closed femoral shaft fracture
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作者 毛吉刚 《外科研究与新技术》 2005年第3期175-175,共1页
To compare and evaluate 3 kinds of treatments of pediatric closed femoral shaft fractures.Methods Seventy-nine patients were divided into 3 groups and treated using hip spica casting after skeletal traction,unilateral... To compare and evaluate 3 kinds of treatments of pediatric closed femoral shaft fractures.Methods Seventy-nine patients were divided into 3 groups and treated using hip spica casting after skeletal traction,unilateral multifunctional fixation and plate fixation.The result were evaluated according to clinical function,time to union,complications,radiology examination and the economic cost.Results Both time to union and economic cost of the external fixation group were shorter than that of the skeletal traction group and plate fixation group.Conclusion The unilateral multi-functional external fixation is an ideal solution to pediatric close femoral shaft fractures.7 refs,3 tabs. 展开更多
关键词 Comparison of three kinds of treatment for pediatric closed femoral shaft fracture
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ON THE COEFFICIENTS OF DIFFERENTIATED EXPANSIONS AND DERIVATIVES OF CHEBYSHEV POLYNOMIALS OF THE THIRD AND FOURTH KINDS 被引量:3
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作者 Eid H.DOHA Waleed M.ABD-ELHAMEED Mahmoud A.BASSUONY 《Acta Mathematica Scientia》 SCIE CSCD 2015年第2期326-338,共13页
Two new analytical formulae expressing explicitly the derivatives of Chebyshev polynomials of the third and fourth kinds of any degree and of any order in terms of Chebyshev polynomials of the third and fourth kinds t... Two new analytical formulae expressing explicitly the derivatives of Chebyshev polynomials of the third and fourth kinds of any degree and of any order in terms of Chebyshev polynomials of the third and fourth kinds themselves are proved. Two other explicit formulae which express the third and fourth kinds Chebyshev expansion coefficients of a general-order derivative of an infinitely differentiable function in terms of their original expansion coefficients are also given. Two new reduction formulae for summing some terminating hypergeometric functions of unit argument are deduced. As an application of how to use Chebyshev polynomials of the third and fourth kinds for solving high-order boundary value problems, two spectral Galerkin numerical solutions of a special linear twelfth-order boundary value problem are given. 展开更多
关键词 Chebyshev polynomials of the third and fourth kinds expansion coefficients generalized hypergeometric functions boundary value problems
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ANALYSIS OF COEXISTENCE OF TWO KINDS OF MACRO-DEFECTS IN CUP-CUP AXISYMMETRIC COMBINED EXTRUSION
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作者 Li Miaoquan and Wu Shichun Northwestern Polytechnical University 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1990年第1期58-66,共9页
In this paper, the relationships between the region of the two coexisting kinds of macro-defects and the reduction in area, as well as between the region and the relative residual thickness of the billet are studied f... In this paper, the relationships between the region of the two coexisting kinds of macro-defects and the reduction in area, as well as between the region and the relative residual thickness of the billet are studied for the cup-cup axisymmetric combined extrusion, on the basis of the analytical expression obtained by the upper-bound approach. The presented model and conclusions are confirmed by the experimental results in this paper. 展开更多
关键词 CUP ANALYSIS of COEXISTENCE of TWO kinds of MACRO-DEFECTS IN CUP-CUP AXISYMMETRIC COMBINED EXTRUSION
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Comparison between Two Kinds of Methods of Locating Acupoints 
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作者 Ding Yidan,Li Jingming(Medical College of Jinan University) 《中国针灸》 CAS CSCD 北大核心 1995年第S2期375-375,共1页
ComparisonbetweenTwoKindsofMethodsofLocatingAcupoints¥DingYidan,LiJingming(MedicalCollegeofJinanUniversity)T... ComparisonbetweenTwoKindsofMethodsofLocatingAcupoints¥DingYidan,LiJingming(MedicalCollegeofJinanUniversity)Theproportionalmea... 展开更多
关键词 Comparison between Two kinds of Methods of Locating Acupoints
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Comparison of four kinds of hla genotyping kits
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《中国输血杂志》 CAS CSCD 2001年第S1期367-,共1页
关键词 Comparison of four kinds of hla genotyping kits
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The description of a new kind and three new types of medusae nematocysts in the Xiamen Harbour, China
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作者 Xu Zhenzu and Wang Wenqiao Department of Oceanography, Xiamen University, Xiamen, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1991年第3期441-445,共5页
A new kind of nematocyst, heteromorphore, and three new types of nematocysts, microbasic spino-mastigophore, microbasic undulata-mastigophore, microbasic laevis-mastigophore, are described from medusae of the Xiamen H... A new kind of nematocyst, heteromorphore, and three new types of nematocysts, microbasic spino-mastigophore, microbasic undulata-mastigophore, microbasic laevis-mastigophore, are described from medusae of the Xiamen Harbour and discussed by comparison with the results of other research workers. 展开更多
关键词 China The description of a new kind and three new types of medusae nematocysts in the Xiamen Harbour
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Seven Kinds of Animals in Imminent Danger
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《China's Foreign Trade》 1995年第9期19-19,共1页
To protect the ecological balance and the environment for our existence, China has organized the projects to Rescue Seven Kinds of Animals, the panda, ibis, Yangtze crocodile, Hainan deer, David’s deer, big nosed ant... To protect the ecological balance and the environment for our existence, China has organized the projects to Rescue Seven Kinds of Animals, the panda, ibis, Yangtze crocodile, Hainan deer, David’s deer, big nosed antelop, and wild horse which are in imminent danger. Panda protection project. From 1992 to the year 2000, 14 panda reserves will be established, covering 4,242 sq km, including 2,479 sq km for the habitation of pandas. The construction and management of the. 13 existing panda reserves will be improved, covering 5,380 sq kin. And 17 new reserve corridors will be set up and 32 stations will be built in 展开更多
关键词 Seven kinds of Animals in Imminent Danger
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Some Kinds of New Composite Solutions of a Kind of Coupled Schrodinger Equation
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作者 Yili Na Baojun Dong Taogetusang 《Journal of Applied Mathematics and Physics》 2015年第11期1376-1385,共10页
With the help of the method that combines the first kind of elliptic equation with the function transformation, some kinds of new composite solutions of a kind of coupled Schr?dinger equation are constructed. First, a... With the help of the method that combines the first kind of elliptic equation with the function transformation, some kinds of new composite solutions of a kind of coupled Schr?dinger equation are constructed. First, a kind of function transformation is presented, and then the problem of solving solutions of a kind of coupled Schr?dinger equation can be changed to the problem of solving solutions of the first kind of elliptic equation. Then, with the help of the conclusions of the B?cklund transformation and so on of the first kind of elliptic equation, the new infinite sequence composite solutions of a kind of coupled Schr?dinger equation are constructed. These solutions are consisting of two-soliton solutions and two-period solutions and so on. 展开更多
关键词 A Kind of Coupled Schrodinger Equation Function Transformation Backlund Transformation New Composite Solutions
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China Having Developed 3001 Kinds of RMs of A and B Grade
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《China Standardization》 2005年第3期7-,共1页
It is reported from NRCCRM (the National Research Center for CRMs) that, China has presently developed 1262 kinds of grade A reference materials and 1739 grade B reference materials, involving the fields of the steel,... It is reported from NRCCRM (the National Research Center for CRMs) that, China has presently developed 1262 kinds of grade A reference materials and 1739 grade B reference materials, involving the fields of the steel, the geology, the petroleum, the nuclear material, the environment, the food and the clinical inspection,and etc. The reference materials play an important role in controlling the production quality, maintaining the market order and promoting the scientific and technological advancement. 展开更多
关键词 China Having Developed 3001 kinds of RMs of A and B Grade
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A comparative evaluation of 3 kinds of cecocolon urinary reservoir
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作者 张心男 《外科研究与新技术》 2003年第2期117-118,共2页
Objective To evaluate and compare 3 kinds of cecocloln urinary reservoir. Methods Perm pouch, indiana pouch or detenial cecocolon reservoir has been performed for 37 patients. The outcome was evaluated by urodynamic a... Objective To evaluate and compare 3 kinds of cecocloln urinary reservoir. Methods Perm pouch, indiana pouch or detenial cecocolon reservoir has been performed for 37 patients. The outcome was evaluated by urodynamic and clinically. Results Good continence has been achieved in all patients with an appendiceal continence mechanism. The capacity and intrareservoir pressure of detenial cecocolon was significantly different from penn or indiana pouch 3 months postoperatively (P【0.01) whereas the difference became in no significant 12 months postoperativelly (P】0. 05). The intrareservoir pressure on contraction was lower with penn pouch. Conclusion The penn or modified indiana pouch is better and more ideal as a urinary reservoir whereas the detenial cecocolon pouch is technically simpler. 6 refs,1 tab. 展开更多
关键词 of A comparative evaluation of 3 kinds of cecocolon urinary reservoir
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On Laozi’s View of Desire
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作者 QIN Xiao 《Cultural and Religious Studies》 2023年第8期368-375,共8页
Laozi’s concept of desire has rich ideological connotations,not only referring to reducing personal desires.Laozi’s concept of desire is based on“desire”as human nature,acknowledging the legitimacy and necessity o... Laozi’s concept of desire has rich ideological connotations,not only referring to reducing personal desires.Laozi’s concept of desire is based on“desire”as human nature,acknowledging the legitimacy and necessity of desire and demand.The rational criticism of“having desire”formed by“no desire”is the value pursuit of Laozi’s concept of desire.From both personal physical and mental aspects and social order,“no desire”plays an important guiding role.Nature is the essence of Laozi’s concept of desire,and being in harmony with nature is the best state of desire.Laozi’s concept of desire reveals a deep spirit of love,and the“ethics of love”highlights Laozi’s strong sense of care for the“other”and ethical attitude towards responsibility.Laozi’s contemplation of desire contains a strong humanistic spirit,with the aim of promoting the healthy and sustainable development of life and society. 展开更多
关键词 LAOZI desire view having desires having no desire NATURE KINDNESS
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The Research of the Relationship Between Yangming’s Yixue and His Xinxue
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作者 LIAO Yiming 《Cultural and Religious Studies》 2023年第4期174-182,共9页
Yangming’s Yixue had been developed several times in his life since originated in Longchang.Yangming’s Yixue and his Xinxue are both sides of the same corn.The Yangming’s Yixue can be roughly divided into two perio... Yangming’s Yixue had been developed several times in his life since originated in Longchang.Yangming’s Yixue and his Xinxue are both sides of the same corn.The Yangming’s Yixue can be roughly divided into two periods.There were the early and middle period of Yangming’s Yixue,which is intended to explain the principles of Yi Zhuan(《易传》)with the theory of Xinxue.The finish of Yangming’s Yixue was a second stage in Yangming’s later years.From the perspective of form and content,there are differences that cannot be ignored between Yangming’s early and middle period and his later years.In the first stage of Yangming’s study,the“Virtuousness”(贞)in Book of Changes is the principle and nature in university.In the later period,Yangming had not focused on interpreting the“Yi Zhuan”,but on the interpretation of ZhouYi’s(《周易》)principles to supplement the connotation of the propositions of Xinxue.This article intends to understand the relationship between Yangming’s Yixue and his Xinxue by dividing the different stages of Yangming’s Yixue firstly.Then by focusing on the influence of Yangming’s later years’Yixue on his Xinxue,we can observe the relation between his Yixue and Xinxue. 展开更多
关键词 Yangming’s Yixue Conscience is Yi nothing kind outside the mind the four-sentence teaching
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Experimental observation of rat's early-stage fracture healing with different kinds of nerve injuries
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作者 马昕 《外科研究与新技术》 2005年第3期182-182,共1页
To investigate the impact of different kinds of nerve injuries of early-stage fracture healing.Methods Three groups of rats were included in the experiment among which group 1 was inflicted with femoral fracture and T... To investigate the impact of different kinds of nerve injuries of early-stage fracture healing.Methods Three groups of rats were included in the experiment among which group 1 was inflicted with femoral fracture and T10 spinal cord transsection (SCI),group 2 was inflicted with femoral and peripheral nerve resection (PNR),and group 3 with simple femoral fracture as control group.Two weeks after operation the femoral bones were collected for X-ray checking and 2 more weeks later X-ray checking was performed again followed by pathomorphologic exams.Results X-ray result showed no massive calluses in the bones in the 2nd week postoperatively,while in the 4th week,callus appeared with larger size in group 3 than that of group 1 and with smaller size than that of group 2.It was the same with the result of pathomorphologic examining.Cortical bone bridges between fracture point and osteiod were also found in group 2 and there were less normal blood vessels and worse bone remodeling than that of group 3.There were relatively immature calluses with more fibroblast-like cells and disordered bone structure in group 2.Group 3 showed normal healing process and callus structure.Conclusion Early-stage bone fracture healing can be influenced significantly by different kinds of nerve injuries.6 refs,6 figs. 展开更多
关键词 Experimental observation of rat’s early-stage fracture healing with different kinds of nerve injuries
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Research on Fuzzy Decision of Resources Selection in Job-sh op Scheduling for a One-of-a-Kind and Order-Oriented Production System
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作者 L1Jian-jun OUYANGHong-qun X1AOXiang-zhi 《International Journal of Plant Engineering and Management》 2004年第4期222-229,共8页
In a one-of-a-kind and order-orient ed production corporation, job shop scheduling plays an important role in the prod uction planning system and production process control. Since resource selection in job shop sche... In a one-of-a-kind and order-orient ed production corporation, job shop scheduling plays an important role in the prod uction planning system and production process control. Since resource selection in job shop scheduling directly influences the qualities and due dates of produc ts and production cost, it is indispensable to take resource selection into acco unt during job shop scheduling. By analyzing the relative characteristics of res ources, an approach of fuzzy decision is proposed for resource selection. Finall y, issues in the application of the approach are discussed. 展开更多
关键词 one-of-a-kind and order-oriented produ ction job-shop scheduling resource selection fuzzy decision
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行为经济学视角下担保型以物抵债的界定 被引量:2
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作者 汪洋 刘冲 《云南社会科学》 北大核心 2024年第1期13-23,共11页
《合同编通则司法解释》所采取的“债务履行期届满前/后”之标准无法清楚界定担保型以物抵债。界定担保型以物抵债的意义在于准确适用流担保禁止规则,无法清楚界定的深层次原因在于对流担保禁止规则的正当性基础存在认识偏差。从行为经... 《合同编通则司法解释》所采取的“债务履行期届满前/后”之标准无法清楚界定担保型以物抵债。界定担保型以物抵债的意义在于准确适用流担保禁止规则,无法清楚界定的深层次原因在于对流担保禁止规则的正当性基础存在认识偏差。从行为经济学和心理学的研究来看,流担保禁止规则的正当性基础应当是避免债务人因过度自信和盲目乐观而受损。从这个角度出发,可以对以物抵债协议进行再类型化:若债务人最终给付内容不是由其的履行能力决定,或债务人最终给付内容的不确定不会对其造成损失,则以物抵债协议不需要被限制;在其他情况下,有必要对以物抵债协议的效力予以限制。若当事人存在担保的意思,则应通过流担保禁止规则限制以物抵债协议的效力,否则就适用违约金酌减规则。 展开更多
关键词 《合同编通则司法解释》 行为经济学 担保型以物抵债 流担保禁止规则 违约金酌减规则
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一本万殊的智慧:《周易》贲卦悖而不悖的发掘与阐释
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作者 黄金枝 谢永珍 《科学与管理》 2024年第3期30-35,共6页
对贲卦美学思想的研究尚属《周易·贲》的小用,而呈现《周易·贲》之大用的悖而不悖的智慧尚未发掘。通过对《周易·贲》基本意涵的探究,发现同属于《易传》的贲卦在《序卦》和《杂卦》中呈现相悖,即:“贲者,饰也”与“贲,... 对贲卦美学思想的研究尚属《周易·贲》的小用,而呈现《周易·贲》之大用的悖而不悖的智慧尚未发掘。通过对《周易·贲》基本意涵的探究,发现同属于《易传》的贲卦在《序卦》和《杂卦》中呈现相悖,即:“贲者,饰也”与“贲,无色也”,其映现了中国哲学“一本化万殊,万殊归一本”的圆融通贯理念。本文借鉴物理学的三棱镜原理,揭示并科学诠释了《周易·贲》“悖而不悖”的哲学意涵,丰富了《周易·贲》的奥义,打破了《周易·贲》仅仅用在文饰美学“小用”的研究局限,开拓了《周易·贲》悖而不悖智慧的大用,彰显了中国哲学圆融一贯的智慧。 展开更多
关键词 周易 贲卦 文饰 悖而不悖 一本万殊
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