Página 1 dos resultados de 65 itens digitais encontrados em 0.003 segundos

Online Mechanism Design for Electric Vehicle Charging

Gerding, Enrico H.; Robu, Valentin; Stein, Sebastian; Parkes, David C.; Rogers, Alex; Jennings, Nicholas R.
Fonte: International Foundation for Autonomous Agents and Multiagent Systems Publicador: International Foundation for Autonomous Agents and Multiagent Systems
Tipo: Monograph or Book
EN_US
Relevância na Pesquisa
25.96%
Plug-in hybrid electric vehicles are expected to place a considerable strain on local electricity distribution networks, requiring charging to be coordinated in order to accommodate capacity constraints. We design a novel online auction protocol for this problem, wherein vehicle owners use agents to bid for power and also state time windows in which a vehicle is available for charging. This is a multi-dimensional mechanism design domain, with owners having non-increasing marginal valuations for each subsequent unit of electricity. In our design, we couple a greedy allocation algorithm with the occasional "burning" of allocated power, leaving it unallocated, in order to adjust an allocation and achieve monotonicity and thus truthfulness. We consider two variations: burning at each time step or on-departure. Both mechanisms are evaluated in depth, using data from a real-world trial of electric vehicles in the UK to simulate system dynamics and valuations. The mechanisms provide higher allocative efficiency than a fixed price system, are almost competitive with a standard scheduling heuristic which assumes non-strategic agents, and can sustain a substantially larger number of vehicles at the same per-owner fuel cost saving than a simple random scheme.; Engineering and Applied Sciences

Does Uncertainty Matter? A Stochastic Dynamic Analysis of Bankable Emission Permit Trading for Global Climate Change Policy

Zhang, Fan
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Relevância na Pesquisa
25.96%
Emission permit trading is a centerpiece of the Kyoto Protocol which allows participating nations to trade and bank greenhouse gas permits under the Framework Convention on Climate Change. When market conditions evolve stochastically, emission trading produces a dynamic problem, in which anticipation about the future economic environment affects current banking decisions. In this paper, the author explores the effect of increased uncertainty over future output prices and input costs on the temporal distribution of emissions. In a dynamic programming setting, a permit price is a convex function of stochastic prices of electricity and fuel. Increased uncertainty about future market conditions increases the expected permit price and causes a risk-neutral firm to reduce ex ante emissions so as to smooth out marginal abatement costs over time. The convexity results from the asymmetric impact of changes in counterfactual emissions on the change of marginal abatement costs. Empirical analysis corroborates the theoretical prediction. The author finds that a 1 percent increase in electricity price volatility measured by the annualized standard deviation of percentage price change is associated with an average decrease in the annual emission rate by 0.88 percent. Numerical simulation suggests that high uncertainty could induce substantially early abatements...

State and Trends of the Carbon Market 2012

Kossoy, Alexandre; Guigon, Pierre
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
25.96%

State and Trends of the Carbon Market 2003

Lecocq, Franck; Capoor, Karan
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
25.96%
The emerging carbon market encompasses both project-based emission reduction transactions, whereby a buyer participates in the financing of a project which reduces greenhouse gases (GHGs) emissions, compared with what would have happened otherwise, and gets some of the emission reductions (ERs) thus generated in return; and, trades of GHG emission allowances allocated under existing, or incoming, cap-and-trade GHG emissions control regimes. This Review of the state and trends of the carbon market as of November 2003, based on material provided by Evolution Markets LLC, Natsource LLC and PointCarbon, and on direct interviews with market participants, suggest that: volume exchanged on the carbon market has more than doubled since 2002; buyers are governments, and public-private partnerships like the Prototype Carbon Fund; in 2003, nine out of ten tones of emission reductions originate from projects located in transition economies or developing countries; prices differ depending on the segment of the market, and on the structure of the transaction; allowance markets dominate in number of transactions, but volume exchanged remains small compared with project-based transactions; and, because of long lead time between project preparation and first "yield" of emission reductions...

A genetic algorithm for solving the first price sealed bid auction in communication networks

Portilla Figueras, José Antonio; Salcedo Sanz, Sancho; García Díaz, Pilar; Hackbarth Planeta, Klaus Dietrich
Fonte: World Scientific and Engineering Academy and Society (WSEAS) Publicador: World Scientific and Engineering Academy and Society (WSEAS)
Tipo: info:eu-repo/semantics/conferenceObject; publishedVersion
ENG
Relevância na Pesquisa
36.3%
This paper shows the first result obtained in the application of economic mechanisms for the efficient assignment of resources in communication networks. The final objective is to determine which Service Provider will carry their traffic over the network of a Network Provider, which will be the most profitable route and which price the ISPs will pay for it to the Network provider. As the price is a key driver a good approach to select the ISP may be an auction mechanism. The implementation of these kind of auction mechanisms becomes a NP complete problem which is solved in this paper using novel metaheuristics, specifically a genetic algorithm.

State and Trends of the Carbon Market 2012

Kossoy, Alexandre; Guigon, Pierre
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Working Paper; Publications & Research
EN_US
Relevância na Pesquisa
25.96%

Dynamic channel allocation in satellite and wireless networks

Sun, Jun, 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 165 p.
ENG
Relevância na Pesquisa
16.51%
The objective of this thesis is to understand how to utilize wireless channels in a fair and efficient manner within a multi-users communication environment. We start by exploring the allocation of a single wireless downlink fading channel among competing users. The allocation of a single uplink multiacccess fading channel is studied as well. With multiple parallel fading channels, a MAC protocol based on pricing is proposed to allocate network resource according to users' demand. We also investigate the use of parallel transmissions and redundant packets to reduce the file transmission delay. Specifically, we develop a novel auction-based algorithm to allow users to fairly compete for a downlink wireless fading channel. We first use the second-price auction mechanism whereby user bids for the channel, during each time-slot, based on the fade state of the channel, and the user that makes the highest bid wins use of the channel by paying the second highest bid. Under the assumption that each user has a limited budget for bidding, we show the existence of a Nash equilibrium strategy. And the Nash equilibrium leads to a unique allocation for certain channel state distribution. We also show that the Nash equilibrium strategy leads to an allocation that is pareto optimal. We also investigate the use of another auction mechanism...

Coalition Formation and Combinatorial Auctions; Applications to Self-organization and Self-management in Utility Computing

Marinescu, Dan C.; Paya, Ashkan; Morrison, John P.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
16.51%
In this paper we propose a two-stage protocol for resource management in a hierarchically organized cloud. The first stage exploits spatial locality for the formation of coalitions of supply agents; the second stage, a combinatorial auction, is based on a modified proxy-based clock algorithm and has two phases, a clock phase and a proxy phase. The clock phase supports price discovery; in the second phase a proxy conducts multiple rounds of a combinatorial auction for the package of services requested by each client. The protocol strikes a balance between low-cost services for cloud clients and a decent profit for the service providers. We also report the results of an empirical investigation of the combinatorial auction stage of the protocol.; Comment: 14 pages

Privacy-Preserving English Auction Protocol with Round Efficiency

Xiong, Hu; Chen, Zhong
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 27/10/2010
Relevância na Pesquisa
46.39%
A privacy-preserving English auction protocol with round efficiency based on a modified ring signature has been proposed in this paper. The proposed protocol has three appealing characteristic: First, it offers conditional privacy-preservation: on the one hand, the bidder is anonymous to the public, on the other hand, only the collaboration of auctioneer and registration manager can reveal the true identity of a malicious bidder. Second, it does not require to maintain a black list which records the evicted malicious bidders. Finally, it is efficient: it saves the communication round complexity comparing with previously proposed solutions.

Brandt's Fully Private Auction Protocol Revisited

Dreier, Jannik; Dumas, Jean-Guillaume; Lafourcade, Pascal
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
36.17%
Auctions have a long history, having been recorded as early as 500 B.C. Nowadays, electronic auctions have been a great success and are increasingly used. Many cryptographic protocols have been proposed to address the various security requirements of these electronic transactions, in particular to ensure privacy. Brandt developed a protocol that computes the winner using homomorphic operations on a distributed ElGamal encryption of the bids. He claimed that it ensures full privacy of the bidders, i.e. no information apart from the winner and the winning price is leaked. We first show that this protocol -- when using malleable interactive zero-knowledge proofs -- is vulnerable to attacks by dishonest bidders. Such bidders can manipulate the publicly available data in a way that allows the seller to deduce all participants' bids. Additionally we discuss some issues with verifiability as well as attacks on non-repudiation, fairness and the privacy of individual bidders exploiting authentication problems.; Comment: Africacrypt 2013, Le Caire : Egypt (2013)

Quantum Auctions using Adiabatic Evolution: The Corrupt Auctioneer and Circuit Implementations

Guha, Saikat; Hogg, Tad; Fattal, David; Spiller, Timothy; Beausoleil, Raymond G.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
16.39%
We examine a proposed auction using quantum states to represent bids and distributed adiabatic search to find the winner. When the auctioneer follows the protocol, the final measurement giving the outcome of the auction also destroys the bid states, thereby preserving privacy of losing bidders. We describe how a dishonest auctioneer could alter the protocol to violate this privacy guarantee, and present methods by which bidders can counter such attacks. We also suggest possible quantum circuit implementations of the auctions protocol, and quantum circuits to perpetrate and to counter attacks by a dishonest auctioneer.; Comment: 26 pages, 10 figures, accepted for publication by International Journal of Quantum Information (IJQI)

Quantum Auctions

Hogg, Tad; Harsha, Pavithra; Chen, Kay-Yut
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/04/2007
Relevância na Pesquisa
26.62%
We present a quantum auction protocol using superpositions to represent bids and distributed search to identify the winner(s). Measuring the final quantum state gives the auction outcome while simultaneously destroying the superposition. Thus non-winning bids are never revealed. Participants can use entanglement to arrange for correlations among their bids, with the assurance that this entanglement is not observable by others. The protocol is useful for information hiding applications, such as partnership bidding with allocative externality or concerns about revealing bidding preferences. The protocol applies to a variety of auction types, e.g., first or second price, and to auctions involving either a single item or arbitrary bundles of items (i.e., combinatorial auctions). We analyze the game-theoretical behavior of the quantum protocol for the simple case of a sealed-bid quantum, and show how a suitably designed adiabatic search reduces the possibilities for bidders to game the auction. This design illustrates how incentive rather that computational constraints affect quantum algorithm choices.; Comment: 38 pages, 3 figures

Analysis of Digital Knapsack Based Sealed Bid Auction

Chodisetti, Navya
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/05/2014
Relevância na Pesquisa
36.59%
The need of totally secure online auction has led to the invention of many auction protocols. But as new attacks are developed, auction protocols also require corresponding strengthening. We analyze the auction protocol based on the well-known mathematical public-key knapsack problem for the design of asymmetric public-key knapsack trapdoor cryptosystem. Even though the knapsack system is not cryptographically secure, it can be used in certain auction situations. We describe the limitations of the protocol like detecting and solving the tie between bidders, malicious behavior of participants and also selection of price set by the seller and offer solutions.; Comment: 17, 6 figures

A Novel Approach to Fully Private and Secure Auction: A Sealed Bid Knapsack Auction

Ibrahim, Maged hamada
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/11/2012
Relevância na Pesquisa
36.56%
In an electronic auction protocol, the main participants are the seller, a set of trusted auctioneer(s) and the set of bidders. In this paper we consider the situation where there is a seller and a set of n bidders intending to come to an agreement on the selling price of a certain good. Full private or bidder-resolved auction means that this agreement is reached without the help of trusted parties or auctioneers. Therefore, only the seller and the set of bidders are involved, the role of the auctioneers becomes obsolete in this case. property.We propose a new technique for the design of a full private sealed-bid auction protocol.; Comment: 10 pages

On Communication Protocols that Compute Almost Privately

Comi, Marco; DasGupta, Bhaskar; Schapira, Michael; Srinivasan, Venkatakumar
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
16.51%
A traditionally desired goal when designing auction mechanisms is incentive compatibility, i.e., ensuring that bidders fare best by truthfully reporting their preferences. A complementary goal, which has, thus far, received significantly less attention, is to preserve privacy, i.e., to ensure that bidders reveal no more information than necessary. We further investigate and generalize the approximate privacy model for two-party communication recently introduced by Feigenbaum et al.[8]. We explore the privacy properties of a natural class of communication protocols that we refer to as "dissection protocols". Dissection protocols include, among others, the bisection auction in [9,10] and the bisection protocol for the millionaires problem in [8]. Informally, in a dissection protocol the communicating parties are restricted to answering simple questions of the form "Is your input between the values \alpha and \beta (under a predefined order over the possible inputs)?". We prove that for a large class of functions, called tiling functions, which include the 2nd-price Vickrey auction, there always exists a dissection protocol that provides a constant average-case privacy approximation ratio for uniform or "almost uniform" probability distributions over inputs. To establish this result we present an interesting connection between the approximate privacy framework and basic concepts in computational geometry. We show that such a good privacy approximation ratio for tiling functions does not...

An Alloy Verification Model for Consensus-Based Auction Protocols

Mirzaei, Saber; Esposito, Flavio
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.44%
Max Consensus-based Auction (MCA) protocols are an elegant approach to establish conflict-free distributed allocations in a wide range of network utility maximization problems. A set of agents independently bid on a set of items, and exchange their bids with their first hop-neighbors for a distributed (max-consensus) winner determination. The use of MCA protocols was proposed, $e.g.$, to solve the task allocation problem for a fleet of unmanned aerial vehicles, in smart grids, or in distributed virtual network management applications. Misconfigured or malicious agents participating in a MCA, or an incorrect instantiation of policies can lead to oscillations of the protocol, causing, $e.g.$, Service Level Agreement (SLA) violations. In this paper, we propose a formal, machine-readable, Max-Consensus Auction model, encoded in the Alloy lightweight modeling language. The model consists of a network of agents applying the MCA mechanisms, instantiated with potentially different policies, and a set of predicates to analyze its convergence properties. We were able to verify that MCA is not resilient against rebidding attacks, and that the protocol fails (to achieve a conflict-free resource allocation) for some specific combinations of policies. Our model can be used to verify...

A Cryptographic Moving-Knife Cake-Cutting Protocol

Manabe, Yoshifumi; Okamoto, Tatsuaki
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/02/2012
Relevância na Pesquisa
36.29%
This paper proposes a cake-cutting protocol using cryptography when the cake is a heterogeneous good that is represented by an interval on a real line. Although the Dubins-Spanier moving-knife protocol with one knife achieves simple fairness, all players must execute the protocol synchronously. Thus, the protocol cannot be executed on asynchronous networks such as the Internet. We show that the moving-knife protocol can be executed asynchronously by a discrete protocol using a secure auction protocol. The number of cuts is n-1 where n is the number of players, which is the minimum.; Comment: In Proceedings IWIGP 2012, arXiv:1202.4229

Mathematical Models of Coordination Mechanisms in Multi-Agent Systems

Terán,Juan; Aguilar,José L; Cerrada,Mariela
Fonte: CLEI Electronic Journal Publicador: CLEI Electronic Journal
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2013 EN
Relevância na Pesquisa
36.51%
The good performance of a set of computer systems based on agents depends on the coherence degree and coordination between their activities. The study of coordination problem is an important topic for designers and researchers in the multi-agents systems field. There are several coordination mechanisms in the current literature, being the auction and the contract net the most popular ones. These mechanisms allow the agents to allocate resources and tasks to achieve their objectives. This paper aims to present formal models of the auction and the contract net as coordination mechanisms in multi-agents systems based on FIPA (Foundation for Intelligent Physical Agents) Protocols. Mathematical equations describe the different parameters characterizing the auction and the contract net mechanisms; they allow define a generic structure of each mechanism and groups of agents can create several instances of them to coordinate their needs