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1.
In this work, we study the Asanov Finsler metric F=α(β2/α2 gβ/α 1)1/2exp{(G/2)arctan[β/(hα) G/2]}, where α=(αijyiyj)1/2 is a Riemannian metric and β=biyj is a 1-form, g∈(-2,2), h=(1-g2/4)1/2, G=g/h. We give the necessary and sufficient condition for Asanov metric to be locally projectively flat, i.e., α is projectively flat and β is parallel with respect to α. Moreover, we proved that the Douglas tensor of Asanov Finsler metric vanishes if and only if β is parallel with respect to α.  相似文献   

2.
Let R be a ring, a ,b ∈ R, ( D , α ) and (G , β ) be two generalized derivations of R . It is proved that if aD ( x ) = G ( x )b for all x ∈ R, then one of the following possibilities holds: (i) If either a or b is contained in C , then α = β= 0 and there exist p , q ∈ Qr ( RC) such that D ( x )= px and G ( x )= qx for all x ∈ R;(ii) If both a and b are contained in C , then either a = b= 0 or D and G are C-linearly dependent;(iii) If neither a nor b is contained in C , then there exist p , q ∈ Qr ( RC) and w ∈ Qr ( R) such that α ( x ) = [ q ,x] and β ( x ) = [ x ,p] for all x ∈ R, whence D ( x )= wx-xq and G ( x )= xp + avx with v ∈ C and aw-pb= 0.  相似文献   

3.
INTRODUCTION Throughout this paper, we shall work with a filtered complete probability space (?,F,(Ft),P) sat-isfying the usual conditions. Let B=(Bt)t≥0 be a stan-dard Brownian motion with B0=0. Denote by ú the set of all non-negative real numbers. Recall that a diffusion process X starting at x≥0 is called the square of a Bessel process of dimension δ>0 if d X t = δd t 2 | X t |d Bt , X 0= x, (1) Clearly, this equation has a unique non-negative strong solution X, i.e., …  相似文献   

4.
Let Γd2nbe the set of trees with a given diameter d having a perfect matching,where 2n is the number of vertex.For a tree T in Γd2n,let Pd+1be a diameter of T and q = d m,where m is the number of the edges of perfect matching inPd+1.It can be found that the trees with minimal energy in Γd2nfor four cases q = d 2,d 3,d 4,[d2],and two remarks aregiven about the trees with minimal energy in Γd2nfor2d 33q d 5 and [d2] + 1 q2d 33 1.  相似文献   

5.
1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｉｎｔｈｅｐａｓｔｄｅｃａｄｅｏｒｓｏ ,ｔｈｅｅｘｉｓｔｅｎｃｅｏｆｇｌｏｂａｌａｔ ｔｒａｃｔｏｒｓａｎｄｔｈｅｅｓｔｉｍａｔｅｓｏｆｔｈｅｉｒＨａｕｓｄｏｒｆｆａｎｄｆｒａｃｔａｌｄｉｍｅｎｓｉｏｎｓｈａｖｅｂｅｅｎｉｎｖｅｓｔｉｇａｔｅｄｆｏｒｎｕｍｅｒｏｕｓｄｉｓｓｉｐａ ｔｉｖｅｎｏｎｌｉｎｅａｒｐａｒｔｉａｌｄｉｆｆｅｒｅｎｔｉａｌｅｑｕａｔｉｏｎｓｗｈｉｃｈａｒｅａｕ ｔｏｎｏｍｏｕｓ[1～ 4 ].Ｔｈｅｎｏｎ ａｕｔｏｎｏｍｏｕｓｉｎｆｉｎｉｔｅ ｄｙｎａｍｉ…  相似文献   

6.
Consider the positive d-dimensional lattice d (d≥2) with partial ordering ≤, let {XK; K ∈ d } be i.i.d. random vari- ables taking values in a real separable Hilbert space (H, ||·||) with mean zero and covariance operator ∑, and set partial sums SN =∑K≤NXK, K , N ∈ d . Under some moment conditions, we obtain the precise asymptotics of a kind of weighted infinite series for partial sums SN as ε 0 by using the truncation and approximation methods. The results are related to the convergence rates of the law of the logarithm in Hilbert space, and they also extend the results of (Gut and Spǎtaru, 2003).  相似文献   

7.
In this paper, we consider some polynomial (α,β)-metrics, and discuss the sufficient and necessary conditions for a Finsler metric in the form F=α a1β a2β2/α a4β4/α3 to be projectively flat, where ai (i=1,2,4) are constants with a1≠0, α is a Riemannian metric and β is a 1-form. By analyzing the geodesic coefficients and the divisibility of certain polynomials, we obtain that there are only five projectively flat cases for metrics of this type. This gives a classification for such kind of Finsler metrics.  相似文献   

8.
This research highlights the learning of female offenders on a 20-day tailor-made experiential adventure education course (Women in Action) delivered by Outward Bound New Zealand. The aims of the course were to increase self-awareness, to develop an understanding of the concept of choice and self responsibility, to improve communication skills and to effectively influence others. Twenty-seven women were interviewed immediately after the course and 14 of these, three months post-course. Most women indicated that their self-confidence had increased and they had become more self-aware. Key factors in facilitating learning opportunities for the women were the instructors and the course environment both physical and social. The holistic course approach provided physical, creative, emotional and reflective opportunities, enabling all the women to develop personally. The challenge of applying their learning on return to prison was highlighted by some participants.
Never did I think that

My life could be changed

In so many ways.

But the challenges I've faced

From being here Lord I Know

That I can make it.

Cos I gotta keep on

Moving on in life

Won't let my spirit fall

Walk on walk on.

Some people tell me

I'd never change.

But now I've seen the light

More clear in every kind of way

I'm alive today

No more worries on my shoulders

I'm gonna make it

Oh yes I am.

Cos I gotta keep on

Moving on in life

Won't let my spirit fall

Walk on walk on.

(Poem by T – Women in Action participant)  相似文献   

9.
In this study we examined procedures for assessing model-data fit of item response theory (IRT) models for mixed format data. The model fit indices used in this study include PARSCALE's G2 , Orlando and Thissen's S − X2 and S − G2 , and Stone's χ2* and G2* . To investigate the relative performance of the fit statistics at the item level, we conducted two simulation studies: Type I error and power studies. We evaluated the performance of the item fit indices for various conditions of test length, sample size, and IRT models. Among the competing measures, the summed score-based indices S − X2 and S − G2 were found to be the sensible and efficient choice for assessing model fit for mixed format data. These indices performed well, particularly with short tests. The pseudo-observed score indices, χ2* and G2* , showed inflated Type I error rates in some simulation conditions. Consistent with the findings of current literature, the PARSCALE's G2 index was rarely useful, although it provided reasonable results for long tests.  相似文献   

10.
The aim of this research is to characterize the development of fatigue damage by means of stress-strain hysteresis. Experiments were conducted on 14 specimens made of cold-finished unannealed AISI 1018 steel. Results demonstrate that the mechanical hysteresis loop areas, when plotted as a function of the number of loading cycles, show significant variations and demonstrate the three principal stages concerning the progress of the fatigue failure--initial accommodation, accretion of damage and terminal failure. These three stages of fatigue are marked by the transitions at cycles N2 and N3. Experimental results show that although fatigue life Nf ranges from 2644 cycles to 108 992 cycles, the ratios of N2/Nf and N3/Nf tend to be stable： N2/Nf=I 0.7%, N3/Nf=91.3%.  相似文献   

11.
Let k,m,n be positive integers,and k≥2,α∈(0,1],0＜r＜min {m,n} an integer,d=r (m-r)/(k α),and iff∈ Ck,α(Rm,R″),A =Cr(f)= {x ∈ Rm ,rank(Df(x))≤r},thenf(A)is d-null.Thus the statement posed by Arthur Sard in 1965 can be completely solved when k≥2.  相似文献   

12.
INTRODUCTION One century ago, Hilbert announced his famous 23 problems. The Hilbert’s Fourth Problem is to characterize the (not-necessarily-reversible) distance functions on an open subset in ún such that straight lines are shortest paths. Distance functions induced by a Finsler metric are regarded as smooth ones. Thus Hilbert’s Fourth Problem in the smooth case is to characterize Finsler metric on an open subset in ún whose geodesics are straight lines. Finsler metric on an ope…  相似文献   

13.
Let Bnp={x ∈ Rn‖|x ‖p≤l} be the unit ball ofp norm in the n-dimensional normed space p. The formula for the volume of Bnp was obtained and its asymptotic properties were found out as n→∞and p→∞.  相似文献   

14.
Reviews     

The Year Book of Education 1952. Pp. xii + 612. London : Evans Bros., 1952. 63s.

A Survey of Rewards and Punishments in Schools : A Report based on Researches carried out by M. E. Highfield and A. Pinsent. National Foundation for Educational Research in England and Wales Publication No. 3. Pp. xxiv+432. London: Newnes Educational Publishing Co., 1952. 42s.

Leisure the Basis of Culture. By Josef Pieper. Pp. 169. London: Faber &; Faber, 1952. 10s. 6d.

Philosophy of Education. By William Heard Kilpatrick. Pp. x+465. New York: Macmillan, 1951. 36s.

A Select Bibliography of Adult Education in Great Britain. Edited by T. Kelly. Pp. xii+84. London: National Institute of Adult Education, 1952. 12s. 6d.

The English Universities and Adult Education. By S. G. Raybould. Pp. xiii +169. London: W.E.A., 1951. 7s 6d.  相似文献   

15.
A discriminant method for optimizing activity in nuclear medicine studies is validated by comparison with ROC （received operating characteristic）-curves. The method is tested in 21 single photon emission computerized tomography （SPECT）, performed with a cardiac phantom. Three different lesions （Lb L2 and L3） were placed in the myocardium-wall by pairs fbr each SPECT. Three activities （84, 37 or 18.5 MBq） of 99mTc were used as background. Linear discriminant analysis was used to select the parameters that characterize image quality among the measured variables in the images [（Background-to-Lesion （B/Li） and Signal-to-Noise （S/N） ratios）]. Two clusters with different image quality （P=0.021 ） were obtained. The ratios B/Lj, B/L2 and B/L3 are the parameters used to construct the function with 100% of cases correctly classified into the clusters. The value of 37 MBq was the lowest tested activity for which good results for the B/Li ratios were obtained. The result coincides with the applied ROC-analysis （r=0.89）.  相似文献   

16.
1 Introduction We consider the finite digraphs that do not havemultiple arcs or loops , but pairs of opposite arcs areallowed.LetD=(V,A) be a digraph , whereVisthe set of vertices andAis the set of arcs .If there isan arc (x,y) fromxtoy,thenthe vertexxis …  相似文献   

17.
Abstract

The effectiveness of a peer review process for online graduate students is predicated on a balance between social- and task-directed communications. The defining criteria of learning communities are presented to illustrate the operational meaning of social and the criteria for Critical Thinking used to illustrate the operational meaning of task response types. The social responses were further categorized as an opinion/evaluative or anecdotal/reflective comment and task responses subcategorized as either a content or style comment. The hypothesis that a significant difference would be found between the social and task responses was accepted as was the second hypothesis that there would be a significant difference between the content and style responses.  相似文献   

18.
Short notices     

Sources for the History of Education. Edited by G. W. J. Higson. Pp. x, 196. London: The Library Association, 1967. 96s. (72s. to L.A. members).

Philosophy and Education. International Seminar Proceedings, March 23–25, 1966. Pp. iv, 157. Toronto: Ontario Institute for Studies in Education (Monograph Series No. 3), 1967. No price.

Disciplines of Education. By Ivor Morrish. Pp. 336. London: Allen &; Unwin, 1967. 40s.

Principles of Psychological Measurement. By G. C. Helmstadter. Pp. xx, 248, London: Methuen, 1966. 36s.

Human Learning and Memory: Selected Readings. Edited by N. J. Slamecka. Pp. ×, 543. Oxford University Press, 1967, 46s.

Education, Interaction and Social Change. By H. L. Hodgkinson. Pp. xxii, 228. London: Prentice‐Hall, 1967. 48s.

The Social Context of the School. By S. John Eggleston. Pp. xii, 116. London: Routledge and Kegan Paul, 1967. 15J. Paperback 75. 6d.

A Critical Approach to Children's Literature. Edited by Sara Innis Fenwick. Pp. 129. London: University of Chicago Press, 1967. 33s. 6d.

The Educationally Retarded and Disadvantaged. Edited by Paul A. Witty. Pp. xiii, 384. London: Chicago University Press, 1967. 41 s.

Group Study for Teachers. By Elizabeth Richardson. Pp. 130. London: Routledge and Kegan Paul (Students Library of Education), 1967. 15s.

Advances in the Teaching of Modern Languages. Volume 2. Edited by G. Mathieu. Pp. ix, 214. Oxford and London: Pergamon Press, 1967. 35s.

John Locke. By M. V. G. Jeffreys. Pp. 120. London: Methuen, 1967. 25s. Paperback 12s. 6d.

The Foundations of 20th Century Education in England. By E. J. R. Eaglesham. Pp. xi, 115. London: Routledge and Kegan Paul, 1967. 15s. Paperback 7s. 6d.

Local History and the Teacher. By R. Douch. Pp. ix, 214. London: Routledge and Kegan Paul, 1967. 21s. Limp edition, 125. 6d.

Adult Education in India. By W. E. Styler. Pp. vii, 114. Oxford University Press, 1967. 8s. 6d.

Malaysia and Its Neighbours. By J. M. Gullick. Pp. xiii, 194. London: Rout‐ledge and Kegan Paul, 1967. 25s. (Paperback 12s. 6d.).

Other Schools and Ours. By Edmund J. King. Pp. vii, 360. (Third Edition). New York and London: Holt, Rinehart and Winston, 1967. 35s.

The Necessary Revolution in American Education. By Francis Keppel. Pp. xiv, 201. New York and London: Harper and Row, 1966. $5.95.

The American Influence on English Education. By W. H. G. Armytage. Pp. x, 118. London: Routledge and Kegan Paul, 1967. 15J. Paperback 7s. 6d.

The Education of Man : The Educational Philosophy of Jacques Maritain. Edited, with an Introduction, by Donald and Idella Gallagher. Pp. 191. University of Notre Dame Press. London: American University Publishers Group, 1967 17s.

Cicero on Moral Obligation. A New Translation of Cicero's De Officiis. With Introduction by John Higginbotham. Pp. 214. London: Faber and Faber, 1967. 30s.

Social Change and the Schools: 1Q18–1944. By Gerald Bernbaum. Pp. viii, 120. London: Routledge and Regan Paul, 1967. 155. Paperback ys. 6d.

A History of Greece to 322 B.C. By N. G. L. Hammond. Pp. xxi, 691. Clarendon Press: Oxford University Press. 1967. 50s.

County and Voluntary Schools. By Sir William Alexander and F. Barraclough. Pp. ix, log. London: Councils and Education Press, 1967. 30J.

Educational Administration in England and Wales: A Bibliographical Guide. By P. H. J. H. Gosden. Pp. 55. Leeds: University of Leeds Institute of Education, 1967. 6s.

Catholic Education in the Western World. Edited by James Michael Lee. Pp. xiv, 324. University of Notre Dame Press. London: American University Publishers Group, 1967. 60s.  相似文献   

19.
Acoustic wave propagation in piezoelectric crystals of classes?43m and 23 is studied. The crystals Tl3VS4 and Tl3TaSe4 (43m) of the Chalcogenide family and the crystal Bi12TiO20 (23) possess strong piezoelectric effect. Because the surface Bleustein-Gulyaev waves cannot exist in piezoelectric cubic crystals, it was concluded that new solutions for shear-horizontal surface acoustic waves (SH-SAWs) are found in the monocrystals using different electrical boundary conditions such as electri- cally “short” and “open” free-surfaces for the unique [101] direction of wave propagation. For the crystal Tl3TaSe4 with coefficient of electromechanical coupling (CEMC) Ke2=e2/(C×g)～1/3, the phase velocity Vph for the new SH-SAWs can be calculated with the following formula: Vph=(Va Vt)/2, where Vt is the speed of bulk SH-wave, Vt=Vt4(1 Ke2)1/2, Va=aKVt4, aK=2[Ke(1 Ke2)1/2-Ke2]1/2, and Vt4=(C44/ρ)1/2. It was found that the CEMC K2 evaluation for Tl3TaSe4 gave the value of K2=2(Vf–Vm)/Vf～0.047 (～4.7%), where Vf～848 m/s and Vm~828 m/s are the new-SAW velocities for the free and metallized surfaces, respectively. This high value of K2(Tl3TaSe4) is significantly greater than K2(Tl3VS4)～3% and about five times that of K2(Bi12TiO20).  相似文献   

20.
Congruences for finite triple harmonic sums   总被引：1，自引：0，他引：1  
Zhao (2003a) first established a congruence for any odd prime p>3, S(1,1,1;p)≡-2Bp-3 (mod p), which holds when p=3 evidently. In this paper, we consider finite triple harmonic sum S(α,β,γ;p) (mod p) is considered for all positive integers α,β,γ. We refer to w=α β γ as the weight of the sum, and show that if w is even, S(α,β,γ;p)≡0 (mod p) for p≥w 3; if w is odd, S(α,β,γ;p)≡rBp≥w (mod p) for p≥w, here r is an explicit rational number independent of p. A congruence of Catalan number is obtained as a special case.  相似文献   

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