The thrust of this paper can be straightforwardly summarized in two propositions. (1)If we accept the principle of punitive damages in tort cases, their appropriateness in at least some suits for breach of contract cannot seriously be questioned. The issue is not so much whether punitive awards should be available for breach of contract, but when. (2)Subject to one possible exception, there is no need for specific restrictions on their availability in breach of contract cases. It is true that there may be a commercial necessity to prevent every breach of contract suit from becoming a potential punitive damages claim: but this, I suggest, can be perfectly well satisfied by applying principles similar to those that already govern damages in torts.
A new efficient normative signature scheme,based on discrete logarithm assumption and factoring assumption is proposed.A zero knowledge proof protocol between the nominee and a third party to verify the signature is also constructed.This signature can be transformed into an undeniable and fail-stop signature if necessary.The efficiency of different nominative signature schemes is also compared.
Because of the possibility of collusion attack,a powerful identification scheme which can guarantee the information be interviewed and drawn by authorized persons is proposed.By using ElGamal signature scheme combined with zero-knowledge proof scheme and Shamir secret sharing technique,a group-oriented identification scheme that consists of n confirmers is designed.Its security is also proved by analysis.
An improved confirmer digital signature scheme was presented based on the analysis of the disadvantages of traditional confirmer signature algorithm and the introduction of zero-knowledge proof. In this scheme, signer need not directly provide his signature to the information, he just need to provide a zero-knowledge to prove that he has the information signature. This zero-knowledge proof includes the signer's identity information. Compared with the traditional confirmer signature algorithms, the improved scheme is simpler and more efficient, and has higher security.
Through the practical study with 132 small enterprises,it concludes that the concrete causes of financing difficulty of small enterprises come from two aspects,namely,the macroscopical financing system and the internal characteristics of small enterprises.It points out that the financing difficulty of small enterprises can be resolved from micro level by inserting incubator system between the credit suppliers and small enterprises.Because the financing services can be shared,decentralization can be changed into intensification,resources can be optimized,so the small enterprises' financing feeler can be extended and their internal defect can be made up.Furthermore,the resultful control can be realized,so the risk of the credit suppliers can be minimized.Finally it puts forward that the development of incubator should be deepened,the service of incubator should be located on the internal characteristics of small enterprises,and incubator should be developed to intelligent intermediary industry,and so on.
The usual manner of describing inequality in a population, involves income distributions. China has experienced rapid income growth, led by reforms which have exacerbated income inequalities. Other components of well-being have been affected as well. Education and health care have become less accessible due to increased costs linked to the decentralization of the financing of such services. The changing face of inequality in China is therefore not confined to income. As such this paper applies new tools to the measure of multidimensional inequalities on wages, education and health. The multidimensional aspect is critical because there may be compensating effects of one form of inequality with respect to others which can change the evolution of overall inequality. Results are submitted to the values of parameters which are included in the formulation of new indices and which translate the Chinese population's aversion to inequalities and the weight it gives to the different dimensions considered. My results show that there has been a significant increase in inequality in China between 1997 and 2000, irrespective of the dimensions one focus on, and that this increase is robust to reasonable variations in the underlying parameters.
Abstract The notion of non-interactive zero-knowledge (NIZK) is of fundamental importance incryptography. Despite the vast attention the concept of NIZK has attracted since its introduction, one question has remained very resistant: Is it possible to construct NIZK schemesfor any NP-language with statistical or even perfect ZK? Groth, Ostrovsky and Sahai recently positively answers to the question by presenting a couple of elegant constructions. However,their schemes pose a limitation on the length of the proof statement to achieve adaptive soundness against dishonest provers who may choose the target statement depending on thecommon reference string (CRS). In this work, we first present a very simple and efficient adaptively-sound perfect NIZKargument system for any NP-language. Besides being the first adaptively-sound statistical NIZK argument for all NP that does not pose any restriction on the statements to be proven,it enjoys a number of additional desirable properties: it allows to re-use the CRS, it can handle arithmetic circuits, and the CRS can be set-up very efficiently without the need foran honest party. We then show an application of our techniques in constructing efficient NIZK schemes for proving arithmetic relations among committed secrets, whereas previousmethods required expensive generic NP-reductions. The security of the proposed schemes is based on a strong non-standard assumption,an extended version of the so-called Knowledge-of-Exponent Assumption (KEA) over bilinear groups. We give some justification for using such an assumption by showing that thecommonly-used approach for proving NIZK arguments sound does not allow for adaptivelysound statistical NIZK arguments (unless NP ae P/poly). Furthermore, we show that theassumption used in our construction holds with respect to generic adversaries that do not exploit the specific representation of the group elements. We also discuss how to avoid thenon-standard assumption in a pre-processing model.
In The Second Theory of Cryptography Conference (TCC 2005), Boneh, Goh, and Nissim proposed a new structure of bilinear groups that have a composite order and a new cryptosystem which is intractable on a decisional problem over the subgroup in such structure [BGN05]. Their proposal, which referred to as the BGN cryptosystem by researchers, receive much attention and is quickly followed by two publications in CRYPTO'05 [BI05, OI05].
The BGN cryptosystem is a dual homomorphic public-key cryptosystem that enables the evaluation of 2-DNF (disjunctive normal form) formulas on ciphertexts. In their work, Boneh et. al. also presented three applications, namely private information retrieval with reduced computational complexity, an e-voting system without non-interactive zero knowledge proofs, and a protocol for universally verifiable computation. Few number of works also produced from the BGN public-key system, include non-interactive zero-knowledge proof (NIZK), obfuscated ciphertext mixing, and signature.
In this thesis, the author performs in-depth study of the BGN public-key cryptosystem and existing literatures on its applications. The author observes two properties of BGN, namely the indistinguishability of the BGN ciphertexts of sum and product of two messages, and the verifiability of elements from composite prime subgroups in BGN settings. The author further proposes three new applications of BGN, namely the protocols for authentication, oblivious transfer, and proof-of-visit respectively.
Progressivism and Philanthropy Lenore T. Ealy (bio) and Steven D. Ealy (bio) Toward the end of the nineteenth century America faced unfamiliar circumstances that seemed to make its traditional social institutions obsolete and threatened the hope for social stability. Steady immigration swelled the ranks and diversity of the urban poor, and headlong industrialization radically changed the ways in which people worked and lived. The growing complexity of social and economic affairs contributed to a widespread belief that a new social and political order must be created. The response of many social critics and scholars, today known broadly as "Progressives," was to forge an approach to social and institutional change rooted in evolutionary philosophy, enamored with scientific objectivism, and often infused with German ideological statism. Traditional Anglo-American common sense and the rule of common law were increasingly suspect as the new "social sciences" emerged with hopes of rationalizing social control. In the decades that followed, most American institutions were organized or re-organized according to the Progressive prescription. The flow of social responsibility was away from more primary, local, and voluntary institutions to those more centralized, professionalized, and tax-supported. This transformation was financed in part by the fledgling philanthropic foundations of Carnegie, Rockefeller, Sage and others who subscribed to some version of the new corporate liberalism. The hierarchical, corporate organization of business entities created a work force with middle-class means and proletarian status, and many of the society's major responsibilities were newly assumed by remote national organizations or assigned to some level of government. By mid-century, in the wake of the New Deal, America's institutions and practices of mutual aid were widely displaced by specialized professionals. Those in need of assistance became clients or "cases." Today, at the turn of another century, new circumstances are rendering the Progressive prescriptions largely obsolete. American society is outgrowing the institutions the Progressives designed for it. The practical virtue and utility of classical liberal principles have triumphed over the ideologies of socialism and statism. Government administration has been shown to suffer from and to reinforce significant knowledge problems. The electronic revolution has suggested and enabled a more horizontal corporate organization in which more and more working people are self-managed. In short, the centralizing thrust of the 20th century seems to be giving way to a decentralizing tendency in the 21st. The purpose of this paper is to foster better understanding of the origins and rationale of the Progressive "old order" and of its continuing impact on American philanthropy. Drawing upon dozens of readings from Progressive-era journals and popular magazines, we seek to uncover the intellectual foundations of Progressivism and to identify its strengths and vulnerabilities. Part of our exploration is also intended to understand how we might best articulate a new rationale for philanthropic enterprises that are today working to return social responsibility to local communities and to support the emergence of new forms of mutual aid and voluntary action. A more robust understanding of the promise of decentralized voluntary action is needed to facilitate the reclamation of responsibility from the outdated, bureaucratic institutions born in the Progressive era. Philanthropists who are today glimpsing the opening of new paths for human action and who wish to encourage the present transformations must understand the challenges in proceeding. A better understanding of the "old order" as well as the entrenchment of contemporary institutions in Progressive assumptions can help promote more effective action in the present. Only when we understand the old assumptions and their compelling hold on the present can we begin fruitfully to challenge these assumptions with a new vision for the future. I. What's Wrong With Charity? A hallmark of the Progressive movement was its effort to reform politics and government administration, to reclaim them from the corrupt patronage system of the party bosses and to apply new, more professional means to accomplishing the ends of government. In the name of reform the Progressives viewed the legitimate ends of the national government as more expansive and substantive than in previous eras. Ever present in the minds of many reformers was the fear of popular revolution, and "the labor question" was of central importance. In the years...
The Laplace equation and the related p-Laplace equation are closely associated with Sobolev spaces. During the last 15 years people have been exploring the possibility of solving partial differential equations in general metric spaces by generalizing the concept of Sobolev spaces. One such generalization is the Newtonian space where one uses upper gradients to compensate for the lack of a derivative. All papers on this topic are written for an audience of fellow researchers and people with graduate level mathematical skills. In this thesis we give an introduction to the Newtonian spaces accessible also for senior undergraduate students with only basic knowledge of functional analysis. We also give an introduction to the tools needed to deal with the Newtonian spaces. This includes measure theory and curves in general metric spaces. Many of the properties of ordinary Sobolev spaces also apply in the generalized setting of the Newtonian spaces. This thesis includes proofs of the fact that the Newtonian spaces are Banach spaces and that under mild additional assumptions Lipschitz functions are dense there. To make them more accessible, the proofs have been extended with comments and details previously omitted. Examples are given to illustrate new concepts. This thesis also includes my own result on the capacity associated with Newtonian spaces. This is the theorem that if a set has p-capacity zero, then the capacity of that set is zero for all smaller values of p.
Local public finance in Korea substantially and significantly has changed for the efficient public provision after 1991 local autonomy. Policy makers are trying to find out the effect of devolution. This paper attempts to examine how local share out of national expenditure (decentralization) affects the growth of regional income. This empirical paper shows the relationship between the increase of local share out of national expenditure and the growth of regional income in Korea. The significant results confirm the connection between them. These findings indicate the transfer effect of central government may cause the regional economy to municipal level rather than province level. For the province level of governments, the finding explains the taxbenefit ratio may not affect the regional income growth.
Abstract. Secure protocols for complicated tasks are usually constructed in two phases. Initially, one designs a protocol that is secure in a semihonest model. Second, zero-knowledge correctness proofs are added to assure correctness and privacy against malicious adversaries. Often the corresponding communication and computational overhead makes this approach intractable in practice. Therefore, we define an intermediate notion of security—consistency. In a consistent protocol, participants always learn if their opponent cheats but cannot complain without violating their own privacy. Thus, a potential victim has to choose between the utility of the correct output and a potential privacy breach. In many contexts, where the long-term reputation of a service provider is more important than the privacy of an individual query, such security notion provides adequate protection with a minimal overhead. Private inference control and adaptive oblivious transfer are the most straightforward examples of such protocols.
This dissertation studies three cryptographic tools: identification schemes---collections of algorithms that enable a party to identify itself to another without revealing information that would facilitate impersonation; zero-knowledge proofs---interactive protocols that efficiently demonstrate the validity of an assertion without conveying any additional knowledge; and plaintext-aware encryption schemes---public-key encryption protocols with the property that the only way to efficiently produce valid ciphertext is to encrypt a message; hence the creator of a ciphertext must know the corresponding plaintext.
We first consider two of the most efficient and best-known identification schemes: GQ and Schnorr. The question of whether they can be proved secure against impersonation under active attack had remained open for over ten years. This dissertation provides such a proof for GQ based on the one-more-RSA-inversion assumption, an extension of the usual one-wayness assumption. It also provides such a proof for Schnorr based on a corresponding discrete-logarithm-related assumption. Both results extend to establish security against impersonation under concurrent attack.
Next, we falsify an assumption, here called KEA2, underlying the Hada-Tanaka 3-round negligible-error zero-knowledge protocol for NP . Providing such a protocol is a challenging problem that has attracted considerable research effort. The fact that KEA2 is false means that we lose one of the few positive results on this subject. To recover the result, we propose a modification of KEA2. After removing a small bug in the Hada-Tanaka protocol that renders it unsound, we obtain a 3-round, negligible-error zero-knowledge protocol for NP under the discrete-logarithm assumption and our new, suitably modified, assumption.
Finally, we address the problem of defining and achieving plaintext-aware encryption in the standard public-key setting. We provide definitions for three notions of increasing strength: PA0, PA1, PA2, chosen so that security against chosen-plaintext attack (IND-CPA1) coupled with PA1 implies security against non-adaptive chosen-ciphertext attack (IND-CCA1), and IND-CPA coupled with PA2 implies security against adaptive chosen-ciphertext attack (IND-CCA2). Towards achieving the new notions, we show that a scheme due to Damgard, denoted DEG, and Cramer-Shoup lite are both PAO under Damgard's DHK0 assumption, and PAI under an extension of DHK0. DEG is thus the most efficient scheme proved IND-CCA1-secure.
ACILITATING urban infrastructure development and promoting the growth of local capital markets are among the most important development objectives for Latin America.For the most part, however, multilateral development organizations such as the World Bank and the Inter-American Development Bank (IDB) have addressed these two development issues separately.Multilateral-sponsored infrastructure development initiatives have focused primarily on providing technical assistance, equity grants, and subsidized bank loans, while capital markets development initiatives have consisted largely of policy-based advising and advocacy of structural reforms.'This Note proposes the use of multilateral-sponsored, local-currency municipal bond insurance to the most credit-worthy Latin American municipalities as a more leveraged, holistic approach to promoting development.Of the few multilateral-sponsored credit guarantee programs that have been implemented, most are designed for private capital investments and, in limited circumstances, sovereign debt securities. 2 A multilateral-sponsored municipal bond insurance program could reduce municipalities' financing costs for specific projects and encourage decentralization within the region, while simultaneously promoting the growth of domestic capital markets by encouraging greater reliance on these markets by Latin *J.D.
In the beginning of the 1980s, Cameroon witnessed a sustained rate of growth, associated essentially with the boom in the oil sector. Increased budgetary and extra-budgetary resources generated by this sector helped to raise the investment rate in the economy, and to maintain a reasonable level of external indebtedness. But after this period of expansion, the country experienced unfavourable economic development caused by a successive decline in the terms of trade, leading to profound imbalances, notably in public finance and the external account. The government subsequently initiated a series of measures to reform its tax system and to adapt it to national economic realities. An efficient and equitable taxation encourages production and the accumulation of national wealth stimulates saving and investments and hence job creation. Such a tax system could, therefore, ensure sustainable growth and development in Cameroon. The study aims to contribute to a better understanding of the evolution of the tax system in Cameroon. In particular, the paper reviews the chronology of the main tax reforms and the evidence on the distributional aspect of taxation. Investigating the issues involved with tax administration and decentralization in the country and local government finances, it also attempts to explore the problems and successes associated with the implementation of tax reforms.
Omar Khadeer Hussain, Elizabeth Chang, Farookh Khadeer Hussain, Tharam S. Dillon
Risk is present in almost every activity. Alternately speaking, almost every activity may have some undesired outcomes which the person doing the activity hopes that they do not occur when it undertakes that particular activity. The quantification of those undesired outcomes can be termed as Risk. Risk is associated with Trust, Security and Privacy. Risk is also associated with transactions, businesses, information systems, environments, networks, partnerships, etc. Generally speaking, Risk signifies the likelihood of financial loss, human casualties, business destruction and environmental damages. It is important to define Risk according to the context of the transaction in order to understand and analyse it better. In the literature Risk has been defined and discussed in areas such as security, health, finance, environment and social life, but there is no systematic study of Risk in decentralized communications, which involves e-business, computer networks and service oriented environments. Hence in this paper, a particular attention is given to define and analyse Risk in the area of Peer-to-Peer business communications, where Risk is every individual and organization?s concern. Also in this paper we develop a risk indicator scale and develop a methodology by which the Riskiness of the peer can be rated according to its behaviour in an interaction. Risk indicator gives an early warning to the party involved and helps avoid disasters.
The literature on knowledge sharing is extensive but organization design received little attention in this literature. A few useful exceptions are Birkinshaw e.a. (2002), Hansen (2002) and Tsai (2002). However, these attempts are yet too limited to fully understand the relationship between organization design choices and knowledge sharing. To contribute in filling this gap, we look at the fundamental organization design dimensions, specialization centralization, formalization, and coordination, in their relationship to the concepts of knowledge and knowledge sharing. While specialization creates firm-specific boundaries to knowledge sharing, coordination is the firm-specific mechanism to overcome these boundaries (Grant, 1996). A multiple case study approach was followed to collect our data, using a questionnaire in the Belgian divisions of two European companies active in the energy and finance sector. Based on a reassessment of the classic organization design literature, we assumed more inter-unit knowledge sharing when: decentralized and informal coordination is used, interdependency between units is low and specialization, reflected in knowledge complexity and unit differences, is low. Our findings indicated that interdependency and
Quality assurance (QA) in the horticultural industry has become well established in Australia; on-farm hazard analysis critical control point (HACCP)-based plans have been adopted due to pressures from supermarkets and other buyers, including fresh markets. Supermarkets' own systems and more general QA systems have been used by growers to meet these new requirements. Two QA systems, Freshcare and Safe Quality Food, have been introduced across the country with moderate success. A review of quality assurance parameters such as chemical residues and microbiological contaminants suggest that these QA systems have achieved some level of assurance. Local pressures, however, are not the only concern when it comes to QA. International demand for safe quality fruit and vegetables has meant that QA systems now need to be designed to satisfy export requirements. In addition to food safety, international demands must also address the environment and workers' health and safety. Many Southeast Asian governments have taken the initiative and developed country-specific QA systems to satisfy export markets and that are suitable for their farmers to use. Countries with schemes in place include Malaysia, Thailand, Indonesia, and Singapore, with other countries, such as the Philippines and Brunei Darussalam, in the process of introducing schemes. This presentation will discuss the status of QA systems in Australia and Southeast Asia, including the pressures behind their establishment, and the major differences between them. The presentation will also focus on the attempt by Southeast Asian governments to address a uniform standard through the development of the Association of Southeast Asian Nations (ASEAN) good agricultural practice (GAP), a GAP standard suitable for use by all 10 ASEAN member countries.
This dissertation presents new constructions and security definitions related to three areas: authentication, cascadable and commutative crytpography, and private set operations. Existing works relevant to each of these areas fall into one of two categories: efficient solutions lacking formal proofs of security or provably-secure, but highly inefficient solutions. This work will bridge this gap by presenting new constructions and definitions that are both practical and provably-secure.
The first contribution in the area of efficient authentication is a provably-secure authentication protocol named HB+. The HB+ protocol is efficient enough to be implemented on extremely low-cost devices, or even by a patient human with a coin to flip. The security of HB+ is based on the hardness of a long-standing learning problem that is closely related to coding theory. HB+ is the first authentication protocol that is both practical for low-cost devices, like radio frequency identification (RFID) tags, and provably secure against active adversaries.
The second contribution of this work is a new framework for defining and proving the security of cascadable crypt osystems, specifically commutative cryptosystems. This new framework addresses a gap in existing security definitions that fail to handle cryptosystems where ciphertexts produced by cascadable encryption and decryption operations may contain some message-independent history. Several cryptosystems, including a new, practical commutative cryptosystem, are proven secure under this new framework.
Finally, a new and efficient private disjointness testing construction named HW is offered. Unlike previous constructions, HW is secure in the face of malicious parties, but without the need for random oracles or expensive zero-knowledge protocols. HW is as efficient as previous constructions and may be implemented using standard software libraries. The security of HW is based on a novel use of subgroup assumptions. These assumptions may prove useful in solving many other private set operation problems. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)