A Necessary and Sufficient Condition for the Existence of an (n,r)-arc in PG(2,q) and Its Applications

ACM Computing Classification System (1998): E.4.Let q be a prime or a prime power ≥ 3. The purpose of this paper is to give a necessary and sufficient condition for the existence of an (n, r)-arc in PG(2, q ) for given integers n, r and q using the geometric structure of points and lines in PG(2, q ) for n > r ≥ 3. Using the geometric method and a computer, it is shown that there exists no (34, 3) arc in PG(2, 17), equivalently, there exists no [34, 3, 31] 17 code.This research was partially supported by Grant-in-Aid for Scientific Research of Japan Society for the Promotion of Science under Contract Number 24540138

Damped Topological Magnons in the Kagom\'{e}-Lattice Ferromagnets

We demonstrate that interactions can substantially undermine the free-particle description of magnons in ferromagnets on geometrically frustrated lattices. The anharmonic coupling, facilitated by the Dzyaloshinskii-Moriya interaction, and a highly-degenerate two-magnon continuum yield a strong, non-perturbative damping of the high-energy magnon modes. We provide a detailed account of the effect for the $S=1/2$ ferromagnet on the kagom\'e lattice and propose further experiments.Comment: 4.5 p + 4 figs main, 8 p + 16 figs supplemental, typos correcte

A uniqueness and regularity criterion for Q-tensor models with Neumann boundary conditions

We give a regularity criterion for a $Q$-tensor system modeling a nematic Liquid Crystal, under homogeneous Neumann boundary conditions for the tensor $Q$. Starting of a criterion only imposed on the velocity field ${\bf u}$ two results are proved; the uniqueness of weak solutions and the global in time weak regularity for the time derivative $(\partial_t {\bf u},\partial_t Q)$. This paper extends the work done in [F. Guill\'en-Gonz\'alez, M.A. Rodr\'iguez-Bellido \& M.A. Rojas-Medar, Sufficient conditions for regularity and uniqueness of a 3D nematic liquid crystal model, Math. Nachr. 282 (2009), no. 6, 846-867] for a nematic Liquid Crystal model formulated in $({\bf u},{\bf d})$, where ${\bf d}$ denotes the orientation vector of the liquid crystal molecules.Comment: 13 page

Inscapes, 1985-01-28

Newsletter published by Governors State University between 1984-1988

On The Expected Values of Distribution of the Sample Range of Order Statistics from the Geometric Distribution

The expected values of the distribution of the sample range of order statistics from the geometric distribution are presented. For n up to 10, algebraic expressions for the expected values are obtained. Using the algebraic expressions, expected values based on the p and n values can be easily computed

Komparativna analiza determinanti inozemnih izravnih ulaganja u Hrvatsku i odabrane zemlje EU

U posljednja dva desetljeća, usporedno s povećanom liberalizacijom i stabiliziranjem tržišta zemalja u razvoju, bilježe se sve veći tokovi inozemnih izravnih ulaganja na globalnoj razini. Konkurencija među zemljama za privlačenjem stranog kapitala sve je veća, te osim zadovoljavanja osnovnih ekonomskih preduvjeta, zemlje moraju osmišljavati i posebne mjere poticaja inozemnim ulagačima. U radu je provedena komparativna analiza determinanti inozemnih izravnih ulaganja u Hrvatsku i dvanaest novih članica Europske unije (EU-12) s ciljem usporedbe odabranih indikatora gospodarskog razvoja te uočavanja prednosti i slabosti Hrvatske u odnosu na odabrane zemlj

The Impact of Inflation on Budgetary Discipline

This paper investigates budgetary rules for an economy characterized by inflation and volatile relative prices. We view the budgetary process as a limited contingencies contract between the treasury and the ministers. The budgetary process allows a minister, whose realized real budget falls short of a threshold, to ask for a treasury, the minister obtains the extra funds needed to meet the expenditure threshold level. The contract sets both the projected budget and the threshold real expenditure that justifies budget revisions. We identify the efficient contract and show that for significant state verification costs and for low volatility, the contract is non contingent (i.e., a nominal contract). For volatility significant enough the contract becomes state contingent -- it reduces the initial allocation [i.e., the projected budget,] and reduces the threshold associated with budgetary revisions. Both adjustments imply that in volatile economies the projected revenue understates the realized budget hence the average budget error is positive. As volatility increases, the contract converges to a full ex-post indexation. Hence, one of the costs of inflation is that nominal contracts lose their disciplining role in determining the real allocation. Instead, the economy shifts towards more costly arrangements like ex-post indexation, where discipline is accomplished by constant monitoring The last part of the paper uses the data from 12 Latin American countries to test the model's predictions. Our tests confirm that in an inflationary environment the planned budget is under-predicting the realized one -- higher inflation increases the budget error and the average budget error is positive.

A Research on an Extensive Reading Class at Kyoto Sangyo University

　本稿は、2003年に京都産業大学において行った多読の授業をもとに、日本の学生の英語力向上に、多読がどの程度効果的であるかを検証したものである。このクラスは再履修クラスで、大半の学生は、英語の授業としては、一週間に一度行われるこのクラスしか履修していない。したがって、このタームの最初と最後に行ったクローズテストに見られる学生の読解能力の推移は、この授業の結果を正確に反映するものとなっていると思われる。実際、この授業を通して、学生の英語を読むスピードは向上し、クローズテストの結果は、読解力向上を示した。更に、事後のアンケートによると、多くの学生が、伝統的教授方法である精読方式よりも、多読形式を好むという結果もでた。この調査は、日本の大学生においても、多読が相当程度、効果的であることを示した

Critical frontier for the Potts and percolation models on triangular-type and kagome-type lattices II: Numerical analysis

In a recent paper (arXiv:0911.2514), one of us (FYW) considered the Potts model and bond and site percolation on two general classes of two-dimensional lattices, the triangular-type and kagome-type lattices, and obtained closed-form expressions for the critical frontier with applications to various lattice models. For the triangular-type lattices Wu's result is exact, and for the kagome-type lattices Wu's expression is under a homogeneity assumption. The purpose of the present paper is two-fold: First, an essential step in Wu's analysis is the derivation of lattice-dependent constants $A, B, C$ for various lattice models, a process which can be tedious. We present here a derivation of these constants for subnet networks using a computer algorithm. Secondly, by means of a finite-size scaling analysis based on numerical transfer matrix calculations, we deduce critical properties and critical thresholds of various models and assess the accuracy of the homogeneity assumption. Specifically, we analyze the $q$-state Potts model and the bond percolation on the 3-12 and kagome-type subnet lattices $(n\times n):(n\times n)$, $n\leq 4$, for which the exact solution is not known. To calibrate the accuracy of the finite-size procedure, we apply the same numerical analysis to models for which the exact critical frontiers are known. The comparison of numerical and exact results shows that our numerical determination of critical thresholds is accurate to 7 or 8 significant digits. This in turn infers that the homogeneity assumption determines critical frontiers with an accuracy of 5 decimal places or higher. Finally, we also obtained the exact percolation thresholds for site percolation on kagome-type subnet lattices $(1\times 1):(n\times n)$ for $1\leq n \leq 6$.Comment: 31 pages,8 figure