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1.
利用初等微分学比较了单参数平均与对数和指数平均的几何组合,发现了使得双向不等式Jp(a,b)1/2-3)/2]和所有a,b>0且a≠b成立的p的最大值和q的最小值,其中Jp(a,b),L(a,b)和I(a,b)分别表示a与b的p-次单参数平均、对数平均和指数平均.  相似文献   

2.
设(F)为定义在区域D内的一族亚纯函数,a(z)和b(z)为两个在D满足a(z)≠b(z)和a(z)≠b(k)(z)以及a(z)(≠)a'(z)的全纯函数,若对于任意的f∈(F),f(z)-a(z)的零点重级至少是k,f(z)和f(k)(z)分担a(z),且当f(z)=b(z)时,f(k)(z)=b(z),那么(F)在...  相似文献   

3.
目的:探讨硫化氢(H2S)对兔左心室心肌细胞电生理特性的影响.方法:用标准微电极细胞内记录技术,观测硫化氢对兔左心室心肌细胞电生理特性的影响.观测指标:静息电位(resting potential,RP)、超射值(over-shoot,OS)、动作电位幅值(amplitude of action po-tential,APA)、0相最大除极速率(maximal rate of depolarization,Vmax)、复极20%、50%和90%时间(20%、50%and 90% of duration of action potential,APD20、APD50and APD90)及复极化平均速度(average rate of repolarization).结果:(1)用50μmol/L NaHS 灌流时,和正常对照组相比,APD50、APD90缩短(P<0.01),复极化平均速度增快(P<0.05).(2)100μmol/L NaHS与对照组比较,APD50、APD90缩短(P<0.01),复极化平均速度增快(P<0.05).和50μmol/L NaHS相比APD50缩短(P<0.01)、APD90缩短(P<0.05)、复极化平均速度增快(P<0.05).(3)200μmol/L NaHS、400μmol/L、1 000μmol/L NaHS可浓度依赖性的使 APA、RP、OS减小(P<0.01),APD20、APD50、APD90缩短(P<0.01),复极化平均速度增快(P<0.01).结论:H2S可浓度依赖性的影响兔左心室心肌细胞电生理特性.  相似文献   

4.
The aim was the reconstruction of a school curriculum in reflective teaching situations within a co‐operative culture. Two working assumptions were considered: (a) teacher development was based on teacher thinking and (b) school organisation followed a co‐operative culture paradigm. The process features were: (a) university team consisted of external advisers; (b) school curriculum and classroom instruction were reviewed by school teachers; (c) case study as a research approach; (d) ethnographic techniques to collect data; (e) data analysis by a computer program; (f) teachers’ reflective cycle to reconstruct practice; and (g) teachers’ portfolios: narrative vignettes, etc. Findings showed: (a) a collaborative process school‐university; (b) teachers’ thinking and attitudinal change; (c) mobilisation of teachers’ talents and values to work together: (i) teacher dyads to reflect on teaching; (ii) advisers’ writing narrative vignettes; (Hi) collegial coaching; and (iv) curriculum materials designed by teachers. Two conclusions can be accepted: (a) teachers’ pedagogical practical knowledge showed diversity of their implicit theories to design action; and (b) teachers’ grounded theory confirmed that the educational action was based on a co‐operative and reflective culture.  相似文献   

5.
Imprinted polymers were prepared for selective removal of Cu(Ⅱ) ions from metal solutions. Three ion-imprinted polymers were synthesized with methacrylic acid (MAA), acrylamide (AA) and N,N'-methylenebisacrylamide (MBAA) respectively as the functional monomers, ethleneglycoldimethacrylate (EGDMA) as the cross-linking agent, 2,2'- azobisisobutyronitrile (AIBN) as the initiator and Cu (Ⅱ) ion as the imprint ion. The template Cu (Ⅱ) ion was removed from the polymer by leaching with a liquid of a 1:1 volumetric ratio of HCl to ethylenediaminetetraacetic acid (EDTA). The capacity and selectivity of Cu(Ⅱ) ion adsorption were investigated with the three imprinted polymers and their non-imprinted counterparts. The polymers have a maximum adsorption capacity at pH 7.0. The isotherm of their batch adsorption of Cu(Ⅱ) ions shows a Langmuir adsorption pattern. Imprinted polymers all have a much higher capacity and higher selectivity of Cu(Ⅱ) adsorption than nonimprinted ones. MAA polymer benefits the most from imprinting. Imprinted MAA polymer has the highest selectivity when used to rebind Cu (Ⅱ) ion from an aqueous solution in the presence of other metal ions. Ion imprinting can be a promising technique of preparing selective adsorbents to separate and preconcentrate metal in a medium of multiple competitive metal ions through solid phase extraction (SPE).  相似文献   

6.
In addition to a literature review of later-life creative activity (as a continuation of previous work or at the onset of later life), the present study provides a blueprint for a course on humanistic creativity in later life. Selected exemplars of well-known creative individuals in the humanities are provided: (1) May Sarton (literature); (2) Marcel Duchamp (painting); (3) Leo w J aná ) ek (music) (4) Martha Graham (dance), and (5) Jessica Tandy (acting). This study includes specific recommendations for the incorporation of these materials into the gerontological curriculum.  相似文献   

7.
通过对函数条件f(a x)=f(a-x),f(x a)=f(x-a)的讨论,以结论的形势给出了它们所对应的函数性质,并辅以一定例子说明它们的应用。  相似文献   

8.
The Differentiated Model of Giftedness and Talent (DMGT) presents the talent development process (P) as the transformation of outstanding natural abilities, or gifts (G), into outstanding systematically developed skills which define expertise, or talent (T) 3 in a particular occupational field. This developmental sequence constitutes the heart of the DMGT. Three types of catalysts help or hinder that process: (a) interpersonal (I) catalysts, like personal traits and self‐management processes; (b) environmental (E) catalysts, like socio‐demographic factors, psychological influences (e.g., from parents, teachers, or peers), or special talent development facilities and programs; and (c) chance (C). The DMGT includes a 5‐level metric‐based (MB) system to operationalize the prevalence of gifted or talented individuals, with a basic ‘top 10 per cent’ threshold for mild giftedness or talent, through successive 10 per cent cuts for moderate, high, exceptional and extreme levels. Complex interactions between the six components are surveyed. The text ends with a proposed answer to a fundamental question: ‘What factor(s) make(s) a difference, on average, between those who emerge among the talented and those who remain average?’  相似文献   

9.
利用初等微分学比较了对数平均与平方根平均和调和平方根平均的凸组合,发现了使得双向不等式aS(a,b)+(1-a)(H)(a,b)<L(a,b)<βS(a,b)+(1-β)(H)(a,b)对所有a,b>0且a≠b成立的a的最大值和β的最小值,其中S(a,b)=√(a2,b2)/2,(H)(a,b)=√2ab√a2+b2和L(a,b)=(a-b)/(loga-logb)分别表示二个正数a与b的平方根平均、调和平方根平均和对数平均.  相似文献   

10.
利用重合度理论,研究了一类三阶泛涵微分方程x'''(t)+a1[x”(t)]^k+a2[x'(t)]^k+a3[x(t)]^k+f(t,x(t),x(t—τ))=p(t)的周期解的存在性,得到了周期解存在的充分条件。  相似文献   

11.
文章主要证明了若图G是阶为n,n>9的连通无爪图,G中至少存在一个非局部连通点或一个单纯点,M(G)={x|x∈V(G),x局部连通}是G的一个连通控制集,则G含有两个分支的2-因子。  相似文献   

12.
谢德三《墨子虚词用法诠释》认为"而"作指示代词犹"此"、作系词犹"乃"、作准系词犹"如"、作副词犹"乃、才",并根据译义把"而"归为介词和连词。这些"而"的语法功能都是连接前后两个谓词性结构,是连词。《墨子虚词用法诠释》忽略了"而"的语法功能,用强赋实义、翻译的方法,对"而"做出的词性归类是值得商榷的。《墨子》中的"然而"大部分都不是凝固结构,"而后""而况""而已""而已矣"都是词与词的组合,《墨子虚词用法诠释》把它们都归为熟语也是有问题的。  相似文献   

13.
This study investigated how best to study a matrix. Fifty-three participants studied a matrix topically (1 column at a time), categorically (1 row at a time), or in a unified way (all at once). Results revealed that categorical and unified study produced higher: (a) performance on relationship and fact tests, (b) study material satisfaction, and (c) associative strategy use than topical study. A supplemental study examined the benefits of adding signals to the unified matrix. Results showed that signaling produced greater use of global associative strategies and greater learning of global relationships. Findings were explained with respect to cognitive load theory. Implications for studying matrices were as follows: (1) do not just study a matrix topically, (2) study a matrix categorically, and (3) study a matrix in a unified way, but do so in a way that fosters comparative associations across multiple topics and categories.  相似文献   

14.
The purpose of this study was twofold: (1) to design a system for constructing Likert attitude scales as supported by the sociopsychological and measurement literature, and (2) using the design to assemble a microcomputer attitude scale for inservice and preservice teachers (n = 281). The results of the study: (1) a 15-step flow chart for designing reliable and valid attitude scales, and (2) a 23-item microcomputer Likert attitude scale with the following characteristics: (a) coefficient alpha 0.89, (b) range of adjusted item-total correlations from 0.29 to 0.62, (c) range of interitem correlations from 0.04 to 0.60, (d) correlation of 0.20 with a mathematics attitude scale and 0.02 with a reading attitude scale, and (e) favorable factor analysis and emotional intensity data.  相似文献   

15.
This study evaluated the use of Interpersonal Process Recall (IPR) with videotape (as opposed to more traditional methods) in improving the effectiveness of practicum students. The practicum students were randomly assigned to one of three treatment groups: (a) a video-IPR, (b) an audio-IPR, and (c) supervision using an audiotape of a regular counseling session. Three judges were asked to rate videotapes of 54 practicum students conducting their final counseling session with a coached client. The judges rated two time-samplings of the final session by means of a scale consisting of three parts: (a) 33 behavioral and feeling items, (b) a single global evaluation representing the normal curve with the baseline divided into eight equal segments, and (c) a request for the judges to write any adjectives or phases that they felt described the practicum student. The results were not as convincing as had been anticipated. This article discusses possible reasons that the results were not convincing and implications the results have for future research within this area of counselor education.  相似文献   

16.
基于柔度测试方法,提出了J积分增量算式;对CT试样,提出了裂纹嘴张开位移V0和加载线裂纹张开位移VLL之间的V0~VLL转换算式,裂纹长度a与弹性模量E计算的简化算式。基于适合同时测试V0和VLL的CT试样设计,对45#钢CT试样进行了多级加-卸载,对CT试样的V0~VLL转换算式进行了试验验证。计算与试验结果表明,新公式具有良好精度。  相似文献   

17.
利用变分法研究非线性奇异微分方程(g(t)|u′(t)|p-2u′(t))′-|u(t)|p-2u(t)=λF(t,u(t)),a.e.t∈[0,T]u(0)-u(T)=gq-1(0)u′(0)-gq-1(T)u′(T)=0(P)周期解的存在性和多重性问题,其中T>0,λ>0,g∈L∞(0,T;R+),ess.infg>0,p2,1p+1q=1,F:[0,T]×RN→R满足下面的假设:(A)对任意的u∈RN,F(t,u)关于t可测;对几乎所有的t∈[0,T],F(t,u)关于u连续可微.并且存在a∈C(R+,R+),b∈L1(0,T;R+),使得对一切的u∈RN,几乎所有的t∈[0,T],有|F(t,u)|a(|u|)b(t),|F(t,u)|a(|u|)b(t).  相似文献   

18.
Concern has been expressed about the vulnerability of the ‘academic profession’ as a consequence of threats from productivism, managerialism and the like (Beck and Young, Br J Sociol Educ 26(2):183–197, 2005). I question the apparent self-understanding of academe as a profession. Referring to thinking from higher education (Barnett, High Educ 40:409–422, 2000a; Educ Phil Theor 32(3):319–326, 2000b; Realizing the University in an age of supercomplexity, 2000c; Stud High Educ 25(3):255–265, 2000d; Lond Rev Educ 2(1):61–73, 2004a; Piper, Are professors professional? The organisation of University examinations, 1994; Taylor 1999), and from the sociology of the professions (in particular Evetts, Int J Sociol Soc Policy 23(4/5):22–35, 2003a; Int Sociol 18(2):395–415 2003b; Curr Sociol 54(1):133–143 2006a; Curr Sociol 54(4):515–531, 2006b), I propose that significant shifts in self-understanding and practice are needed for academe to claim a social role as a ‘profession’.  相似文献   

19.
k-平衡标号是关于顶点数为p,边数为q的图G的一个映射f:V(G)∪E(G)→[p+q],使得在这个映射下,存在一个整数k满足uv∈E(G)都有f(u)+f(v)=k+f(uv)成立.本文提出了可生长标号的概念,主要介绍了对枝树及一类特殊的二级分叉树上的k-平衡标号,猜想任何一个(p,q)-图,若其存在k-平衡称号,则存在可生长k-平衡称号.  相似文献   

20.
In human infancy, 2 criteria for intentional communication are (a) persistence in and (b) elaboration of communication when initial attempts to communicate fail. Twenty-nine chimpanzees (Pan troglodytes) were presented with both desirable (a banana) and undesirable food (commercial primate chow). Three conditions were administered: (a) the banana was delivered (successful communication), (b) half of the banana was delivered (partially successful communication), and (c) the chow was delivered (failed communication). The chimpanzees exhibited persistence in and elaboration of their communication in every condition except when the banana was delivered. Thus, their communication was about a specific item, demonstrating that both intentionality and nonverbal reference are capacities shared by humans with our nearest living relatives, the great apes.  相似文献   

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