18 research outputs found
A New Class of Backward Stochastic Partial Differential Equations with Jumps and Applications
We formulate a new class of stochastic partial differential equations
(SPDEs), named high-order vector backward SPDEs (B-SPDEs) with jumps, which
allow the high-order integral-partial differential operators into both drift
and diffusion coefficients. Under certain type of Lipschitz and linear growth
conditions, we develop a method to prove the existence and uniqueness of
adapted solution to these B-SPDEs with jumps. Comparing with the existing
discussions on conventional backward stochastic (ordinary) differential
equations (BSDEs), we need to handle the differentiability of adapted triplet
solution to the B-SPDEs with jumps, which is a subtle part in justifying our
main results due to the inconsistency of differential orders on two sides of
the B-SPDEs and the partial differential operator appeared in the diffusion
coefficient. In addition, we also address the issue about the B-SPDEs under
certain Markovian random environment and employ a B-SPDE with strongly
nonlinear partial differential operator in the drift coefficient to illustrate
the usage of our main results in finance.Comment: 22 pagea, 1 figur
Product-form solutions for integrated services packet networks and cloud computing systems
We iteratively derive the product-form solutions of stationary distributions
of priority multiclass queueing networks with multi-sever stations. The
networks are Markovian with exponential interarrival and service time
distributions. These solutions can be used to conduct performance analysis or
as comparison criteria for approximation and simulation studies of large scale
networks with multi-processor shared-memory switches and cloud computing
systems with parallel-server stations. Numerical comparisons with existing
Brownian approximating model are provided to indicate the effectiveness of our
algorithm.Comment: 26 pages, 3 figures, short conference version is reported at MICAI
200
Optimal Rate Scheduling via Utility-Maximization for J-User MIMO Markov Fading Wireless Channels with Cooperation
We design a dynamic rate scheduling policy of Markov type via the solution (a
social optimal Nash equilibrium point) to a utility-maximization problem over a
randomly evolving capacity set for a class of generalized processor-sharing
queues living in a random environment, whose job arrivals to each queue follow
a doubly stochastic renewal process (DSRP). Both the random environment and the
random arrival rate of each DSRP are driven by a finite state continuous time
Markov chain (FS-CTMC). Whereas the scheduling policy optimizes in a greedy
fashion with respect to each queue and environmental state and since the
closed-form solution for the performance of such a queueing system under the
policy is difficult to obtain, we establish a reflecting diffusion with
regime-switching (RDRS) model for its measures of performance and justify its
asymptotic optimality through deriving the stochastic fluid and diffusion
limits for the corresponding system under heavy traffic and identifying a cost
function related to the utility function, which is minimized through minimizing
the workload process in the diffusion limit. More importantly, our queueing
model includes both J-user multi-input multi-output (MIMO) multiple access
channel (MAC) and broadcast channel (BC) with cooperation and admission control
as special cases. In these wireless systems, data from the J users in the MAC
or data to the J users in the BC is transmitted over a common channel that is
fading according to the FS-CTMC. The J-user capacity region for the MAC or the
BC is a set-valued stochastic process that switches with the FS-CTMC fading. In
any particular channel state, we show that each of the J-user capacity regions
is a convex set bounded by a number of linear or smooth curved facets.
Therefore our queueing model can perfectly match the dynamics of these wireless
systems.Comment: 53 pages, Originally submitted on June 17, 2010; Revised version
submitted on December 24, 201
Mean-variance hedging based on an incomplete market with external risk factors of non-Gaussian OU processes
In this paper, we prove the global risk optimality of the hedging strategy of
contingent claim, which is explicitly (or called semi-explicitly) constructed
for an incomplete financial market with external risk factors of non-Gaussian
Ornstein-Uhlenbeck (NGOU) processes. Analytical and numerical examples are both
presented to illustrate the effectiveness of our optimal strategy. Our study
establishes the connection between our financial system and existing general
semimartingale based discussions by justifying required conditions. More
precisely, there are three steps involved. First, we firmly prove the
no-arbitrage condition to be true for our financial market, which is used as an
assumption in existing discussions. In doing so, we explicitly construct the
square-integrable density process of the variance-optimal martingale measure
(VOMM). Second, we derive a backward stochastic differential equation (BSDE)
with jumps for the mean-value process of a given contingent claim. The unique
existence of adapted strong solution to the BSDE is proved under suitable
terminal conditions including both European call and put options as special
cases. Third, by combining the solution of the BSDE and the VOMM, we reach the
justification of the global risk optimality for our hedging strategy.Comment: 36 page
Brownian approximations for queueing networks with finite buffers : modeling, heavy traffic analysis and numerical implementations
Ph.D.Jiangang Da