69,450 research outputs found
Determinants of emerging market bond spread : do economic fundamentals matter?
In the 1990s international bond issues from developing countries surged dramatically, becoming one of the fastest-growing devices for financing external development. Their terms have improved as institutional investors have become more interested in emerging market securities and better economic prospects in a number of developing countries. But little is known about what determines the pricing and thus the yield spreads of new emerging market bond issues. The author investigates what determines bond spreads in emerging markets in the 1990s. He finds that strong macroeconomic fundamentals in a country -- such as low domestic inflation rates, improved terms of trade, and increased foreign assets -- are associated with lower yield spreads. By contrast, higher yield spreads are associated with weak liquidity variables in a country, such as a high debt-to-GDP (Gross Domestic Product) ratio, a low ratio of foreign reserves to GDP, a low (high) export (import) growth rate, and a high debt-service ratio. At the same time, external shocks -- as measured by the international interest rate -- matter little in the determination of bond spreads. In the aggregate, Latin America countries have a negative yield curve.Environmental Economics&Policies,Economic Theory&Research,Banks&Banking Reform,Payment Systems&Infrastructure,International Terrorism&Counterterrorism,International Terrorism&Counterterrorism,Economic Theory&Research,Macroeconomic Management,Environmental Economics&Policies,Banks&Banking Reform
A version of the Glimm method based on generalized Riemann problems
We introduce a generalization of Glimm's random choice method, which provides
us with an approximation of entropy solutions to quasilinear hyperbolic system
of balance laws. The flux-function and the source term of the equations may
depend on the unknown as well as on the time and space variables. The method is
based on local approximate solutions of the generalized Riemann problem, which
form building blocks in our scheme and allow us to take into account naturally
the effects of the flux and source terms. To establish the nonlinear stability
of these approximations, we investigate nonlinear interactions between
generalized wave patterns. This analysis leads us to a global existence result
for quasilinear hyperbolic systems with source-term, and applies, for instance,
to the compressible Euler equations in general geometries and to hyperbolic
systems posed on a Lorentzian manifold.Comment: 34 page
Multi-level Turbo Decoding Assisted Soft Combining Aided Hybrid ARQ
Hybrid Automatic Repeat reQuest (ARQ) plays an essential role in error control. Combining the incorrectly received packet replicas in hybrid ARQ has been shown to reduce the resultant error probability, while improving the achievable throughput. Hence, in this contribution, multi-level turbo codes have been amalgamated both with hybrid ARQ and efficient soft combining techniques for taking into account the Log- Likelihood Ratios (LLRs) of retransmitted packet replicas. In this paper, we present a soft combining aided hybrid ARQ scheme based on multi-level turbo codes, which avoid the capacity loss of the twin-level turbo codes that are typically employed in hybrid ARQ schemes. More specifically, the proposed receiver dynamically appends an additional parallel concatenated Bahl, Cocke, Jelinek and Raviv (BCJR) algorithm based decoder in order to fully exploit each retransmission, thereby forming a multi-level turbo decoder. Therefore, all the extrinsic information acquired during the previous BCJR operations will be used as a priori information by the additional BCJR decoders, whilst their soft output iteratively enhances the a posteriori information generated by the previous decoding stages. We also present link- level Packet Loss Ratio (PLR) and throughput results, which demonstrate that our scheme outperforms some of the previously proposed benchmarks
Observing the Dark Scalar Doublet and its Impact on the Standard-Model Higgs Boson at Colliders
If the Standard Model of particle interactions is extended to include a
second scalar doublet , which is odd under an
unbroken Z_{2} discrete symmetry, it may be called the scalar doublet,
because its lightest neutral member, say H^{0}, is one posssible component for
the dark matter of the Universe. We discuss the general phenomenology of the
four particles of this doublet, without assuming that H^{0} is the dominant
source of dark matter. We also consider the impact of this scalar
doublet on the phenomenology of the SM Higgs boson h.Comment: PRD versio
Multi-Cell Massive MIMO in LoS
We consider a multi-cell Massive MIMO system in a line-of-sight (LoS)
propagation environment, for which each user is served by one base station,
with no cooperation among the base stations. Each base station knows the
channel between its service antennas and its users, and uses these channels for
precoding and decoding. Under these assumptions we derive explicit downlink and
uplink effective SINR formulas for maximum-ratio (MR) processing and
zero-forcing (ZF) processing. We also derive formulas for power control to meet
pre-determined SINR targets. A numerical example demonstrating the usage of the
derived formulas is provided.Comment: IEEE Global Communications Conference (GLOBECOM) 201
Goal-directed therapy in intraoperative fluid and hemodynamic management.
Intraoperative fluid management is pivotal to the outcome and success of surgery, especially in high-risk procedures. Empirical formula and invasive static monitoring have been traditionally used to guide intraoperative fluid management and assess volume status. With the awareness of the potential complications of invasive procedures and the poor reliability of these methods as indicators of volume status, we present a case scenario of a patient who underwent major abdominal surgery as an example to discuss how the use of minimally invasive dynamic monitoring may guide intraoperative fluid therapy
- …