126 research outputs found
Environmental analysis for application layer networks
Die zunehmende Vernetzung von Rechnern über das Internet lies die Vision von Application Layer Netzwerken aufkommen. Sie umfassen Overlay Netzwerke wie beispielsweise Peer-to-Peer Netzwerke und Grid Infrastrukturen unter Verwendung des TCP/IP Protokolls. Ihre gemeinsame Eigenschaft ist die redundante, verteilte Bereitstellung und der Zugang zu Daten-, Rechen- und Anwendungsdiensten, während sie die Heterogenität der Infrastruktur vor dem Nutzer verbergen. In dieser Arbeit werden die Anforderungen, die diese Netzwerke an ökonomische Allokationsmechanismen stellen, untersucht. Die Analyse erfolgt anhand eines Marktanalyseprozesses für einen zentralen Auktionsmechanismus und einen katallaktischen Markt. --Grid Computing
Distributed Task Management in Cyber-Physical Systems: How to Cooperate under Uncertainty?
We consider the problem of task allocation in a network of cyber-physical
systems (CPSs). The network can have different states, and the tasks are of
different types. The task arrival is stochastic and state-dependent. Every CPS
is capable of performing each type of task with some specific state-dependent
efficiency. The CPSs have to agree on task allocation prior to knowing about
the realized network's state and/or the arrived tasks. We model the problem as
a multi-state stochastic cooperative game with state uncertainty. We then use
the concept of deterministic equivalence and sequential core to solve the
problem. We establish the non-emptiness of the strong sequential core in our
designed task allocation game and investigate its characteristics including
uniqueness and optimality. Moreover, we prove that in the task allocation game,
the strong sequential core is equivalent to Walrasian equilibrium under state
uncertainty; consequently, it can be implemented by using the Walras'
tatonnement process
Optimizing Wirelessly Powered Crowd Sensing: Trading energy for data
To overcome the limited coverage in traditional wireless sensor networks,
\emph{mobile crowd sensing} (MCS) has emerged as a new sensing paradigm. To
achieve longer battery lives of user devices and incentive human involvement,
this paper presents a novel approach that seamlessly integrates MCS with
wireless power transfer, called \emph{wirelessly powered crowd sensing} (WPCS),
for supporting crowd sensing with energy consumption and offering rewards as
incentives. The optimization problem is formulated to simultaneously maximize
the data utility and minimize the energy consumption for service operator, by
jointly controlling wireless-power allocation at the \emph{access point} (AP)
as well as sensing-data size, compression ratio, and sensor-transmission
duration at \emph{mobile sensor} (MS). Given the fixed compression ratios, the
optimal power allocation policy is shown to have a \emph{threshold}-based
structure with respect to a defined \emph{crowd-sensing priority} function for
each MS. Given fixed sensing-data utilities, the compression policy achieves
the optimal compression ratio. Extensive simulations are also presented to
verify the efficiency of the contributed mechanisms.Comment: arXiv admin note: text overlap with arXiv:1711.0206
Market-based Risk Allocation for Multi-agent Systems
This paper proposes Market-based Iterative Risk Allocation
(MIRA), a new market-based distributed planning
algorithm for multi-agent systems under uncertainty.
In large coordination problems, from power grid
management to multi-vehicle missions, multiple agents
act collectively in order to optimize the performance of
the system, while satisfying mission constraints. These
optimal plans are particularly susceptible to risk when
uncertainty is introduced. We present a distributed planning
algorithm that minimizes the system cost while
ensuring that the probability of violating mission constraints
is below a user-specified level. We build upon the paradigm of risk allocation (Ono
& Williams 2008), in which the planner optimizes not
only the sequence of actions, but also its allocation of
risk among each constraint at each time step. We extend
the concept of risk allocation to multi-agent systems
by highlighting risk as a commodity that is traded
in a computational market. The equilibrium price of
risk that balances the supply and demand is found by
an iterative price adjustment process called tˆatonnement
(also known as Walrasian auction). Our work is distinct
from the classical tˆatonnement approach in that we use
Brent’s method to provide fast guaranteed convergence
to the equilibrium price. The simulation results demonstrate
the efficiency of the proposed distributed planner
The application of variational inequality theory to the study of spatial equilibrium and disequilibrium
Includes bibliographical references (p. 26-29).Supported by the National Science Foundation VPW Program. RII-880361by A. Nagurney
Is economic planning hypercomputational? The argument from Cantor diagonalisation
Murphy [26] argues that the diagonal argument of the number theorist Cantor can be used to elucidate issues that arose in the socialist calculation debate of the 1930s. In particular he contends that the diagonal argument buttresses the claims of the Austrian economists regarding the impossibility of rational planning.We challenge Murphy’s argument, both at the number theoretic level and from the standpoint of economic realism
Nash Social Welfare Approximation for Strategic Agents
The fair division of resources is an important age-old problem that has led
to a rich body of literature. At the center of this literature lies the
question of whether there exist fair mechanisms despite strategic behavior of
the agents. A fundamental objective function used for measuring fair outcomes
is the Nash social welfare, defined as the geometric mean of the agent
utilities. This objective function is maximized by widely known solution
concepts such as Nash bargaining and the competitive equilibrium with equal
incomes. In this work we focus on the question of (approximately) implementing
the Nash social welfare. The starting point of our analysis is the Fisher
market, a fundamental model of an economy, whose benchmark is precisely the
(weighted) Nash social welfare. We begin by studying two extreme classes of
valuations functions, namely perfect substitutes and perfect complements, and
find that for perfect substitutes, the Fisher market mechanism has a constant
approximation: at most 2 and at least e1e. However, for perfect complements,
the Fisher market does not work well, its bound degrading linearly with the
number of players.
Strikingly, the Trading Post mechanism---an indirect market mechanism also
known as the Shapley-Shubik game---has significantly better performance than
the Fisher market on its own benchmark. Not only does Trading Post achieve an
approximation of 2 for perfect substitutes, but this bound holds for all
concave utilities and becomes arbitrarily close to optimal for Leontief
utilities (perfect complements), where it reaches for every
. Moreover, all the Nash equilibria of the Trading Post mechanism
are pure for all concave utilities and satisfy an important notion of fairness
known as proportionality
Reaching an equilibrium of prices and holdings of goods through direct buying and selling
The Walras approach to equilibrium focuses on the existence of market prices
at which the total demands for goods are matched by the total supplies. Trading
activities that might identify such prices by bringing agents together as
potential buyers and sellers of a good are characteristically absent, however.
Anyway, there is no money to pass from one to the other as ordinarily
envisioned in buying and selling. Here a different approach to equilibrium --
what it should mean and how it may be achieved -- is offered as a constructive
alternative.
Agents operate in an economic environment where adjustments to holdings have
been needed in the past, will be needed again in a changed future, and money is
familiar for its role in facilitating that. Marginal utility provides relative
values of goods for guidance in making incremental adjustments, and with money
incorporated into utility and taken as num\`eraire, those values give money
price thresholds at which an agent will be willing to buy or sell. Agents in
pairs can then look at such individualized thresholds to see whether a trade of
some amount of a good for some amount of money may be mutually advantageous in
leading to higher levels of utility. Iterative bilateral trades in this most
basic sense, if they keep bringing all goods and agents into play, are
guaranteed in the limit to reach an equilibrium state in which the agents all
agree on prices and, under those prices, have no interest in further adjusting
their holdings. The results of computer simulations are provided to illustrate
how this works
- …