Blockchain Papers

Joe Kilian

No abstract is available for this record.

Stefano D’Amiano, Giovanni Di Crescenzo

No abstract is available for this record.

Tsuyoshi Ueyama, Toshio Fukuda, Tsunehiko Sugiura, Akira Sakai · 5 authors

This paper deals with the self-organization of a group of multiple robotic systems consisting of several or a number of autonomous robots, such as the Cellular Robotic System (CEBOT). In paticular, in this paper, we will present the self-organization of the hierarchical structure of the CEBOT as one of the decentralized autonomous robotic systems. The structural organization is simulated based on the idea of interdependence between autonomous robots, which is derived from the model of group organization of human beings. That is, groups are organized and leaders emerge from the interdependence of the individuals. Additionaley, an evaluation method for the hierarchical architecture is also discussed to evaluate the structure of the whole system. This paper will represent simulation results of self-organization of hierarchical structure on the basis of a given task model. The sensitivity of the organization of the decentralized autonomous robotic systems is also discussed in the simulation.

Toshio Fukuda, Go Iritani, Fumihito Arai, Tsunehiko Sugiura · 6 authors

In this research, we address the organization of group behavior on decentralized autonomous robotic systems. Collective group behavior is exhibied in the natural world, such as by ants and fish, in teamwork in sports and by the human society. Therefore, research on group behavior of decentralized autonomous robotic systems can be regarded as one of the research fields of Artificial Life. Decentralized autonomous robotic systems refer to multiple robotic systems including many autonomous robots, such as the Cellular Robotic System (CEBOT). The CEBOT, which has been studied by the authors, consists of a number of robotic units called "cells". In the research on the CEBOT, it is necessary to evolve a cooperative group behavior effectively in the system, since a well-organized group behavior is required to carry out given tasks efficiently and influences its perfor-mance ability. In order to organize the behavior in a dynamic environment, we proposed a concept of "self-recognition" for decision making of the behavior in a robotic group. In this paper, in addition to the proposed concept, we will show the organization and adaptation of group behavior with the coordination of intention, and represent some simulation results with the coordination of intention.

A. A.

No abstract is available for this record.

Oded Goldreich

A proof is whatever convinces me. Shimon Even (1935–2004) The glory attached to the creativity involved in finding proofs makes us forget that it is the less glorified process of verification that gives proofs their value. Conceptually speaking, proofs are secondary to the verification process, whereas technically speaking, proof systems are defined in terms of their verification procedures. The notion of a verification procedure presumes the notion of computation and furthermore the notion of efficient computation. This implicit stipulation is made explicit in the definition of NP , where efficient computation is associated with deterministic polynomial-time algorithms. However, as argued next, we can gain a lot if we are willing to take a somewhat non-traditional step and allow probabilistic verification procedures. In this chapter, we shall study three types of probabilistic proof systems, called interactive proofs, zero-knowledge proofs , and probabilistic checkable proofs . In each of these three cases, we shall present fascinating results that cannot be obtained when considering the analogous deterministic proof systems. Summary: The association of efficient procedures with deterministic polynomial-time procedures is the basis for viewing NP-proof systems as the canonical formulation of proof systems (with efficient verification procedures). Allowing probabilistic verification procedures and, moreover, ruling by statistical evidence gives rise to various types of probabilistic proof systems. Indeed, these probabilistic proof systems carry a probability of error (which is explicitly bounded and can be reduced by successive applications of the proof system), yet they offer various advantages over the traditional (deterministic and errorless) proof systems. […]

Alfredo De Santis, Giovanni Di Crescenzo, Guiseppe Persiano

No abstract is available for this record.

José Ramos López, Isabel Rodríguez, Pilar González Navarro, José María Peiró Silla · 6 authors

Analysis of sports-related demands of potential users of an organization is a very important aspect of its functioning and helps it cover its demands and needs. In the context of sports, analysis of demands related to planning and provision for sports areas is important for various social agents and is a relevant contribution of psychology towards development and improvement of sports management. This article presents the results of a survey from 625 users of 43 facilities in the Spanish Autonomous Community of Valencia. The survey was centred on their demands respecting provision for sports facilites. Three main aspects were considered: values and function of the practice of sport for respondents, users' preferences for the type of facility that should be used, and certain preferences and opinions about facilities' management and ownership. Outstanding results are: great centrality of sport for respondents, predominant orientation towards sport as a means of leisure and recreation, a preference for state-owned facilities, even though respondents believe private ones are better managed, consideration of in-door pavilions and covered sports centres as facilities that should get priority in local building plans, and a preference for decentralization of new facilities. This analysis can be of great help in order to plan the provision for new sports services and infrastructure, and a supporting tool in the management of facilities.

Lev Freinkman, С А Титов

No abstract is available for this record.

Mercy Tembon

The government of Cameroon like that of many Sub-S aharan African countries is
\nfaced with dwindling revenues and cannot provide the required fmances for the education
\nsector. Since many other developing countries are facing similar fmancial constraints,
\npolicy options have been proposed for the recovery of costs as a way of revitalizing and
\nimproving the quality of education in these countries. The introduction of user charges is
\none of the more prominent options that applies to all levels of education. In light of the
\neducational financing situation in Cameroon, this study sets out to assess the possibility
\nof implementing this option. It therefore seeks to analyze how secondary schools are
\nfmanced and to measure private direct costs of secondary education so as to determine
\nparental willingness to spend on schooling.
\nA household and a school survey were conducted in Mezam Division of the North
\nWest Province of Cameroon. 335 households in urban and rural areas were involved in
\nthe household survey, while 16 principals and 750 students, selected from 16 secondary
\nschools, took part in the school survey. Results from these surveys indicate that in
\ngovernment secondary schools, although tuition is provided free, parents are obliged to
\nmeet the costs of books and uniforms. Moreover, because government funding is
\ninadequate, by default, parents are obliged to contribute further towards the provision of
\nadditional facilities in these schools through the Parent-Teacher Association (PTA). Thus
\nparents incur substantial costs for their children's education, in relation to household
\nincome and Gross National per Capita Income. The study also reveals that in the private
\neducational sector, fees and other parental contributions, including PTA levies, form an
\nimportant source of finance for secondary schools. Parents of government school students
\nvalue the education of their children highly, and therefore indicated willingness to pay
\nmore, even though they already incur substantial costs. The findings further indicate that
\nwillingness to pay will be increased if the quality of education is improved. However,
\nability to pay is related to family income and number of children, which have important
\nimplications for equity which are discussed in the thesis. Finally the study reveals that the
\nhighly centralized financing policy and practice in government secondary schools does not
\ntake into account the fmancial capacity of communities and private individuals
\nsufficiently.
\nThe thesis argues that, in order to improve access, quality and efficiency of
\neducational provision, an appropriate cost-sharing strategy needs to be developed to
\nfinance government secondary schools, with provision of scholarships or other selective
\nassistance to the most needy. The thesis suggests further that, efforts be made to explore
\nparental willingness and the inherent self help tradition of the people, by encouraging
\nlocal management and fmancing of schools. Hence support from individual users and
\ncontributions from local communities through Parent-Teacher-Associations should be
\nactively solicited. It also suggests that the decentralization of educational management of
\nschools will go a long way towards enhancing educational quality and efficiency. This
\nwill require some adjustments to the existing financing structures, and changes in the
\nregulation and management of the education system. The successful implementation of
\nthese recommendations require immense political will on the part of the policy makers.

Tony L Eng

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1994.

Jeni Klugman

No abstract is available for this record.

Jeni Klugman

Decentralization has been a popular theme in development thinking and practice due to the impact of decentralisation of government expenditures and revenues upon human development. This survey explores the extensive literature on decentralisation, revealing the lack of quantitative and rigorous studies. A detailed analysis of the various dimensions of decentralisation - participation, financing and comparative priorities - and of the relevant effects upon efficiency, resource availability and equity, enable the author to draw some interesting lessons from its theory and practice.

Joan Boyar, Carsten Lund, René Peralta

No abstract is available for this record.

Oded Goldreich

No abstract is available for this record.

Marschall W. Raffel, Norma K. Raffel

Before World War II, Czechoslovakia was among the most developed European countries with an excellent health care system. After the Communist coup d'etat in 1948, the country was forced to adapt its existing health care system to the Soviet model. It was planned and managed by the government, financed by general tax money, operated in a highly centralized, bureaucratic fashion, and provided service at no direct charge at the time of service. In recent years, the health care system had been deteriorating as the health of the people had also been declining. Life expectancy, infant mortality rates, and diseases of the circulatory system are higher than in Western European countries. In 1989, political changes occurred in Czechoslovakia that made health care reform possible. Now health services are being decentralized, and the ownership of hospitals is expected to be transferred to communities, municipalities, churches, charitable groups, or private entities. Almost all health leaders, including hospital directors and hospital department heads, have been replaced. Physicians will be paid according to the type and amount of work performed. Perhaps the most important reform is the establishment of an independent General Health Care Insurance Office financed directly by compulsory contributions from workers, employers, and government that will be able to negotiate with hospitals and physicians to determine payment for services.

Janet K. Wanzek, F. Larry Leistritz

In the 1980's, in the US across the board, domestic manufacturers have have faced foreign competition with an increased disadvantage with imports. Domestic businesses, including those in rural areas, have had to struggle with restructuring their businesses, decentralizing them, outsourcing, relocating overseas, go out of business altogether or to reduce their business size or workforce numbers. Economic initiatives like 'Growing North Dakota' attempted to educate North Dakota citizens to the necessity of their state increasing it's growth in manufacturing and in ways they could help these industries grow such as financing these industries at favorable terms, aiding in the transfer of technology commercialization or assisting such technologies. By aiding the manufacturing sector this was deemed as aiding in the diversification of the North Dakota economy.

Olympia Icochea

The author studies Chile's educational reforms in the eighties, and assesses their successes and failures in terms of quality of teaching. The reforms rested principally on two aspects: decentralized administration (municipal authorities assuming responsibility) and the application of market economic mechanisms for financing schools. Chile's democratic government subsequently added a number of measures that the reforms lacked, such as increasing outlay to the sector and improving educational quality in subsidized schools. However, the success of these reforms is still uncertain.

S. M. Ageev

T. It is shown that any free action of a zero-dimensional compact group G on the О·-dimensional Menger compactum Mn is О·-universal for free actions, and that the orbit space MnjG is В«-classifying. Nonexistence of equivariant mappings between Mn+m and Mn implies that the orbit space R/Ap has infinite dimension, where R is any compact ANR-space with free action of the group Ap of p-adic integers. Knowledge of such nonexistence would then permit proof of the Hilbert-Smith conjecture under the assumption of finite dimensionality for the orbit space.

Kaoru Kurosawa

No abstract is available for this record.

Jonathan Harris

In the winter of 1989-90 the unintended consequences of Mikhail S. Gorbachev's program of political and economic refonn had become obvious to all but his most optimistic spokesmen. The General Secretary's attempt to create a new ideology of perestroika by grafting "bourgeois" and "social democratic" concepts onto the conventional ideology of the Communist Party of the Soviet Union (CPSU) had divided the party, created immense ideological confusion, and led to the formation of non-Communist and anti-Communist political organizations. The attempt to shift authority from party officials to elected soviets on the union and republican levels had led to the emergence of separatist and nationalist movements in many of the USSR's republics, including the RSFSR. The decentralization of the state's administration of the economy and the encouragement of both private and cooperative economic activity had failed to reverse the deterioration of economic conditions. As anxiety swept through the CPSU, orthodox party leaders called for the establishment of an autonomous Communist Party for the RSFSR to counter Gorbachev's policies and to "save Soviet Russia" from destruction.

Serge Vaudenay

No abstract is available for this record.

William A. Wulf, Alec Yasinsac, Katie S. Oliver, Ramesh Peri

Distributed systems have long relied on shared secrets to ensure the authenticity of principals. Public key systems and zero knowledge proofs of identity have reduced this reliance. We offer a method of remote authentication that can be used with no advance shared knowledge by parties, and that allows parties to increase their confidence in the authenticity of a suspicious party to an arbitrary level. Note: Abstract extracted from PDF text

Mihir Bellare, Phillip Rogaway

We argue that the random oracle model—where all parties have access to a public random oracle—provides a bridge between cryptographic theory and cryptographic practice. In the paradigm we suggest, a practical protocol P is produced by first devising and proving correct a protocol PR for the random oracle model, and then replacing oracle accesses by the computation of an “appropriately chosen” function h. This paradigm yields protocols much more efficient than standard ones while retaining many of the advantages of provable security. We illustrate these gains for problems including encryption, signatures, and zero-knowledge proofs.