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91.
Richard P. Kent IV 《Geometriae Dedicata》2004,106(1):145-159
We answer a question of J. Anderson's by producing infinitely many commensurability classes of fibered hyperbolic 3-manifolds whose fundamental groups contain subgroups that are locally free and not free. These manifolds are obtained by performing 0–surgery on a collection of knots with the same properties. 相似文献
92.
Wing-Keung Wong Jack Penm Richard Deane Terrell Karen Yann Ching 《Journal of Applied Mathematics and Decision Sciences》2004,8(4):201-218
With the emergence of new capital markets and liberalization of stock markets in recent years, there has been an increase in investors' interest in international diversification. This is so because international diversification allows investors to have a larger basket of foreign securities to choose from as part of their portfolio assets, so as to enhance the reward-to-volatility ratio. This benefit would be limited if national equity markets tend to move together in the long run. This paper thus studies the issue of co-movement between stock markets in major developed countries and those in Asian emerging markets using the concept of cointegration. We find that there is co-movement between some of the developed and emerging markets, but some emerging markets do differ from the developed markets with which they share a long-run equilibrium relationship. Furthermore, it has been observed that there has been increasing interdependence between most of the developed and emerging markets since the 1987 Stock Market Crash. This interdependence intensified after the 1997 Asian Financial Crisis. With this phenomenon of increasing co-movement between developed and emerging stock markets, the benefits of international diversification become limited. 相似文献
93.
94.
95.
We study the stability and the properties of the ground state of neutral systems containing up to four positively charged
bosons and their antiparticles. Examples are the di-pionium molecule (π
+
π
−)2, which is almost identical to the positronium molecule (e
+
e
−)2, the tri-pionium (π
+
π
−)3, and the quadri-pionium (π
+
π
−)4 molecules. We briefly compare our results on the energy to those on the large-N limit of (π
+
π
−)
N
. We also show that the annihilation probability can be calculated accurately with simple wave functions when one uses the
generalized Schwinger rule.
Received September 5, 1994; accepted for publication October 15, 1994 相似文献
96.
97.
Richard Valenta 《Czechoslovak Journal of Physics》1998,48(9):1035-1048
The purpose of this paper is to solve the coupled non-homogeneous equations derived from the basic classical theory of the
acoustic propagation in visco-thermal fluid. The 1D radial distribution of pressure and temperature inside a spherical object
was found. It is supposed that both acoustic and thermal conditions on a surface of the object are known. The starting equations
are considered in the time domain and their solution was found without initial conditions for steady harmonic motion. 相似文献
98.
99.
100.