Blockchain Papers

Martin P. Grochulla

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Tsz Hon Yuen, Qiong Huang, Yi Mu, Willy Susilo · 6 authors

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Hendrik Tews, Bart Jacobs

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Anguraj Baskar, R. Ramanujam, S. P. Suresh

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Daoshun Wang

Polynomial functions are frequently used in mathematics and computer science. The zero-knowledge proof of the roots of a polynomial function is an important application of zero-knowledge, with both theoretical and practical significance. The zero-knowledge proof of the roots of a polynomial function based on the intractablity of computing the discrete logarithm to solve the multi discrete logarithm problem. The solution to the multi discrete logarithm problem is used as a building block to construct the zero-knowledge proof protocol for the roots of polynomial functions. A theoretical analysis shows that the protocol is secure and reliable.

Authors unavailable

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Aleksander Berentsen, Mariana Rojas Breu, Shouyong Shi

Many countries simultaneously suffer from high inflation, low growth and poorly developed financial sectors. In this paper, we integrate a microfounded model of money and finance into a model of endogenous growth to examine the effects of inflation on welfare, growth and the size of the financial sector. A novel feature is that the innovation sector is decentralized. Financial intermediaries arise endogenously to provide liquidity to this sector. Consistent with the data but in contrast to previous work, reducing inflation generates large growth gains. These large gains cannot be easily reproduced by imposing a cash-in-advance constraint in the innovation sector.

Benjamin Olken, Monica Singhal

Informal payments are a frequently overlooked source of local public finance in developing countries. We use microdata from ten countries to establish stylized facts on the magnitude, form, and distributional implications of this "informal taxation." Informal taxation is widespread, particularly in rural areas, with substantial in-kind labor payments. The wealthy pay more, but pay less in percentage terms, and informal taxes are more regressive than formal taxes. Failing to include informal taxation underestimates household tax burdens and revenue decentralization in developing countries. We propose a simple model of information and enforcement constraints that parsimoniously explains the patterns in the data.

Mira Belenkiy, Melissa Chase, Markulf Kohlweiss, Anna Lysyanskaya

Abstract. Efficient non-interactive zero-knowledge proofs are a powerful tool for solving many cryptographic problems. We apply the recent Groth-Sahai (GS) proof system for pairing product equations (Eurocrypt 2008) to two related cryptographic problems: compact e-cash (Eurocrypt 2005) and simulatable verifiable random functions (CRYPTO 2007). We present the first efficient compact e-cash scheme that does not rely on a random oracle. To this end we construct efficient GS proofs for signature possession, pseudo randomness and set membership. The GS proofs for pseudorandom functions give rise to a much cleaner and substantially faster construction of simulatable verifiable random functions (sVRF) under a weaker number theoretic assumption. We obtain the first efficient fully simulatable sVRF with a polynomial sized output domain (in the security parameter). 1

T. Kleiberg, Piet Van Mieghem

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Sarah Meiklejohn

Non-interactive zero-knowledge proofs, particularly those constructed on top of bilinear groups, have been significantly studied in cryptography and used in a wide variety of applications in recent years. One very powerful suite of techniques for proofs over bilinear groups is the Groth-Sahai proof system, which provides efficient non-interactive witnessindistinguishable and zero-knowledge proofs without relying on any one assumption or language. The Groth-Sahai suite of proofs has already been used in a number of applications, including group signature schemes, anonymous voting, and anonymous credentials. In this paper, we describe a technique that allows us to prove that two GS commitments open to the same value. We then use this technique to create a non-interactive zero-knowledge protocol that satisfies a stronger version of zero-knowledge than the original GS protocol. Finally, we use both these techniques to provide a new extension of the proof system that makes it into a non-interactive zero-knowledge proof of knowledge of an exponent. We then outline new building blocks based on this technique that can be used in a variety of applications. The main application of our technique will involve using it to construct a fully

Michel Abdalla⋆, Céline Chevalier, David Pointcheval

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MA Shi-hua

Flexibility value of enterprise's logistics capability is one of the key factors which influence the quick response to customers in decentralized supply chain.This article analyzed the characteristics of enterprise's logistics capability in decentralized supply chain,defined the flexibility of enterprise's logistics capability and its value,and analyzed the way of calculating the uncertain investment benefits.Then we constructed the model of flexibility value of enterprise's logistics capability based on multistage stochastic mix integer programming and real option through investment.The surpassing sample technology of Latin super cube and Monte Carlo were put forward to solve this problem.This model solved the problem that anomalous value calculation of logistics capability investment was ignored by traditional finance method.Finally a case explained that this model was effective on calculating flexibility value of enterprise's logistics capability.

Ivana Batarelo Kokić, Željka Podrug, Tome Apostoloski

In 2001, Croatia started the process of decentralization of the educational system. The decentralization started in the area of finances, and should be continued in other relevant areas (i.e., decentralization of management, curriculum, and human resources). The decentralization of primary and secondary school finances is based on the transfer of the founding rights to the primary and secondary schools. The founding rights include the obligation for partial financing of educational programs. Due to financial decentralization efforts, significant changes occurred in terms of resource allocation in the last three years. Education financing experts recognize that the main advantages of decentralization are related to the fact that management of expenditures is in the vicinity of schools and it is easier to recognize real needs of the schools. Expenditure norms for primary and secondary education are determined at the level of municipalities and towns. Future development of educational financing in Croatia should focus on clearer educational financing policies that would include: structuring the allocation formula, improvement of the financial status of teachers, and strengthening the leadership and managerial knowledge of teachers and school directors.

Paulo Leitão

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Zaki Brahmi, Mohamed Mohsen Gammoudi

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Rafael Pass, Wei-Lung Dustin Tseng, Douglas Wikström

We show that only languages in BPP have public-coin black-box zero-knowledge protocols that are secure under an unbounded (polynomial) number of parallel repetitions. This result holds both in the plain model (without any setup) and in the bare public key model (where the prover and the verifier have registered public keys). We complement this result by constructing a public-coin black-box zero-knowledge proof based on one-way functions that remains secure under any a priori bounded number of concurrent executions. A key step (of independent interest) in the analysis of our lower bound shows that any public-coin protocol, when repeated sufficiently in parallel, satisfies a notion of “resettable soundness” if the verifier picks its random coins using a pseudorandom function.

Ronald Cramer, Ivan Damgård, Marcel Keller

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Jan Camenisch, Aggelos Kiayias, Moti Yung

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Jolanta Urbanovič

The article probes into factors that determine processes of decentralization in managing the general education system. The study entails a review of pertinent literature and an analysis of the distribution of powers among entities managing the general education system in Lithuania. The study concludes that the education management system in Lithuania is gradually being decentralized and de-concentrated on the basis of the subsidiarity principle. A successful implementation of the decentralization reform requires the following two conditions: political support for proposed changes and the ability of those charged with carrying out the reform. An analysis of literature confirms that decentralization as a process is also a function of factors other than political will and capacity. These factors include trust (the extent of decentralization depends on the central government’s trust in the local government, and vice versa), financial troubles, path dependencies, international developments, etc. An analysis of the distribution of decision making powers in areas of financing and human resources demonstrates that there is a trend towards decentralization, albeit inconsistent due to obstacles on the level of centralized management. The article maintains that there has to be an adequate balance between centralization, which is necessary for the implementation of general national educational objectives, and decentralization, which allows teachers, schoolchildren, parents and the representatives of local communities to participate in education management.

Cristiano Castelfranchi

This chapter presents organizations as a macro-micro notion and device; they presuppose autonomous proactive entities (agents) playing the organizational roles. Agents may have their own powers, goals, relationships (of dependence, trust, etc.). This opens important issues to be discussed: Does cooperation require mentally shared plans? Which is the relationship between individual powers and role powers; personal dependencies and role dependencies; personal goals and assigned goals; personal beliefs and what we have to assume when playing our role; individual actions and organizational actions? What about possible conflicts, deviations, power abuse, given the agents’ autonomy? MultiAgentSystems discipline should both aim at scientifically modeling human organizations, and at designing effective artificial organizations. Our claim is that for both those aims, one should model a high (risky) degree of flexibility, exploiting autonomy and pro-activity, intelligence and decentralized knowledge of roleplayers, allowing for functional violations of requests and even of rules.Request access from your librarian to read this chapter's full text.

Chengming Qi, Shoumei Cui

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Daoshun Wang

The multi discrete logarithm problem and the zero-knowledge proolf protocol were proposed to efficiently solve the zero-knowledge proof of the roots of polynomials,based on the hardness of computing the discrete logarithms.In the protocol,the prover computes the discrete logarithms of each term of the polynomial and obtains A1,A2,…,An,which are sent to the verifier.Based on the value of(A1A2…An)modp,the verifier verifies the prover's ownership of the root.The protocol needs to be executed several rounds to reduce the possibility of cheating.Theoretical analyses show that the chance of successfully cheating decays exponentially with increasing number of rounds,so the protocol is secure and reliable.

圭介 田中, Keisuke Tanaka, 恵太 草川, Keita Xagawa

No abstract is available for this record.