Blockchain Papers

Joe Kilian

No abstract is available for this record.

Stefano D’Amiano, Giovanni Di Crescenzo

No abstract is available for this record.

Annemarie Wouters

New evidence on the quality of health care from public services in Niger is discussed in terms of the relationships between quality, costs, cost-effectiveness and financing. Although structural attributes of quality appeared to improve with the pilot project in Niger, significant gaps in the implementation of diagnostic and treatment protocols were observed, particularly in monitoring vital signs, diagnostic examination and provider-patient communications. Quality improvements required significant investments in both fixed and variable costs; however, many of these costs were basic input requirements for operation. It is likely that optimal cost-effectiveness of services was not achieved because of the noted deficiencies in quality. In the test district of Boboye, the revenues from the copayments alone covered about 34% of the costs of medicines or about 20% of costs of drugs and administration. In Say, user fees covered about 50-55% of the costs of medicines or 35-40% of the amount spent on medicines and cost-recovery administration. In Boboye, taxes plus the additional copayments covered 120-180% of the cost of medicines, or 75-105% of the cost of medicines plus administration of cost recovery. Decentralized management and legal conditions in the pilot districts appeared to provide the necessary structure to ensure that the revenues and taxes collected would be channelled to pay for quality improvements.

Gordon Db, Sam Marafioti, Michael Carter, Hans Kunov · 5 authors

Sunnybrook Health Science Center (Sunnybrook) is a multifacility academic teaching center. In May 1994, Sunnybrook struck an electronic patient record taskforce to develop a strategic plan for the implementation of a comprehensive, facility wide electronic patient record (EPR). The taskforce sought to create a conceptual framework which provides context and integrates decision-making related to the comprehensive electronic patient record. The EPR is very much broader in scope than the traditional paper-based record. It is not restricted to simply reporting individual patient data. By the Institute of Medicine's definition, the electronic patient record resides in a system specifically designed to support users through availability of complete and accurate data, practitioner reminders and alerts, clinical decision support systems, links to bodies of medical knowledge, and other aids [1]. It is a comprehensive resource for patient care. The taskforce proposed a three domain model for determining how the EPR affects Sunnybrook. The EPR enables Sunnybrook to have a high performance team structure (domain 1), to function as an integrated organization (domain 2), and to reach out and develop new relationships with external organizations to become an extended enterprise (domain 3) [2]. Domain 1: Sunnybrook's high performance teams or patient service units' (PSUs) are decentralized, autonomous operating units that provide care to patients grouped by 'like' diagnosis and resource needs. The EPR must provide functions and applications which promote patient focused care, such as cross functional charting and care maps, group scheduling, clinical email, and a range of enabling technologies for multiskilled workers. Domain 2: In the integrated organization domain, the EPR should facilitate closer linkages between the arrangement of PSUs into clinical teams and with other facilities within the center in order to provide a longitudinal record that covers a continuum of care. Domain 3: In the inter-enterprise domain, the EPR must allow for patient information to be exchanged with external providers including referring doctors, laboratories, and other hospitals via community health information networks (CHINs). Sunnybrook will prioritize the development of first domain functionality within the corporate constraints imposed by the integrated organization domain. Inter-enterprise computing will be less of a priority until Sunnybrook has developed a critical mass of the electronic patient record internally. The three domain description is a useful model for describing the relationship between the electronic patient record enabling technologies and the Sunnybrook organizational structures. The taskforce has used this model to determine EPR development guidelines and implementation priorities.

Satoshi Kurihara, Okada Michio

This paper shows study on mechanism for selforganization. A global order is organized by simple and locally coordiztnted actions of autonomous a~ents uldns only very local information, and not by their complex and globally coordinated actions which would use global me~sse pas-~ng and high level strategies. The fundamental factors for establizhing the global order by self-orSuizztion are dimdpztive structure ~ nnd zutocztMytic ~ If an environment where agents exist hun structure and those a4enta hnve some sort of autocatalytic mechanisms within themselves, it is possible to form a global order of nsent8 by their simple and locally coordinated actions. Blind Hunger (Num~okL 1994) is used an example tO dmul&te the self-orsmsisation and coordinated actions of agents and to show the validity of our approach. Behavior-Based AI is a new approach to the study of intelligence and is distinguished from the traditional Knowledge-Based AI approach in many ways. Knowledge-Based AI has traditionaUy emphasized the modeling and building of systems that know~ about some problem domain, and it has produced several successful systems when the domain is limited (e.g. chess). But, this approach seerr~s to be inadequate for systems dealing with autonomous robots, human-machine interaction, etc. Behavior-Based AI, on the other hand, has emphasized the rnodeling and building ofsysterns where there is some sort of in the problem domain. Simple interaction dynamics between agents lead to emergent structure or functionality. An agent interacts directly with the environment, and there is less of a need for modeling the problem dome3n itself. In traditional Multi-Agent Systems, the coordinated actions of agents are modeled by their adjusting with each other. But, there are no adjustment mechanisms in our approach, where agents are non-linear and coordinate by entrainment The system is decentralized, and each agent is autonomous. For example, a robot made by this approach can robustly and flexibly interact with the real-world, where unpredictable changes occur. Th/s research takes as an example for demonstrating the Behavior-Based pproach, since colonies of ants exhibit very interesting behaviors. Even if a single ant only has very few simple capabilities, the behavior fan ant colony as a whole is highly structured. This is the result of coordinated interaction. The fundamental factors for establishing the (black agent: hungry-mode agent, gray agent: normal-mode agent) An order is organized among agents. Hungry-mode agents surround the supply base except for a section to the right. This section becomes an escape route for normai-mode agents. Figure I: Simulation fthe Ant Agent Model emergent structure or functionality are dissipative structure (Nicolis ~kPrigogine 1977) and antocstaiytic mechanisms. Dissipative structure isthe order and structure which are generated ina non-linear non-equilibrium state where there is a flow of energy. The order and structure are maintained by dissipating energy outside of the environment. Theorder can occur more fficiently if each agent has an antocatalytic mechanism. This mechanism isnecessary for ~eneral chemical reactions including reactions in cells. Blind Hunger Dilemma is used for the simulation of the self-organization nd coordinated actions of agents. In this simulation, there are many agents (which model ants) which must get supplies ofenergy. However, there is only one small energy supply base. As a result of the simple habit ’ToUow an ant, an order is organized among agents and they can get energy efficiently (Figure I).

Javad Mohajeri

No abstract is available for this record.

Sigurt Vitols

This paper analyzes the contribution of the German banking system to the modernization of small and medium-sized enterprises (SMEs) in industry. The simultaneous greater relative importance of and relatively high wages in German SMEs appear to be paradoxical in terms of dual labor market theory, which claims that lower wages and greater flexibility in the use of labor are important for helping small firms compensate for their constrained access to capital, R&Dk and skills resources relative to large firms. This paper suggests that the successful modernization of the German small firm sector despite pressure from below from industry-level wage bargaining and strong job protection can be attributed to support from above in terms of an institutional infrastructure helping small firms overcome the organizational deficiencies they face relative to large firm. The decentralized provision of long-term finance and sophisticated financial services for the modernization of SMEs is enabled by a three-tiered federalist form of corporatist organization in the cooperative and savings banks sectors, in which smaller banks at the bottom tier of the organization receive access to refinancing on capital markets and specialized services -- normally only available to large banks -- through the upper tiers of the banking organization.

Charlie Kaufman, Radia Perlman, Mike Speciner

Acknowledgments. 1. Introduction. Roadmap to the Book. What Type of Book Is This? Terminology. Notation. Primer on Networking. Active vs. Passive Attackc. Layers and Cryptography. Authorization. Tempest. Key Escrow for Law Enforcement. Key Escrow for Careless Users. Viruses, Worms, Trojan Horses. The Multi-level Model of Security. Legal Issues. I. CRYPTOGRAPHY. 2. Introduction to Cryptography. What Is Cryptography? Breaking an Encryption Scheme. Types of Cryptographic Functions. Secret Key Cryptography. Public Key Cryptography. Hash Algorithms. Homework. 3. Secret Key Cryptography. Introduction. Generic Block Encryption. Data Encryption Standard (DES). International Data Encryption Algorithm (IDEA). Advanced Encryption Standard (AES). RC4. Homework. 4. Modes of Operation. Introduction. Encrypting a Large Message. Generating MACs. Multiple Encryption DES. CBC Outside vs. Inside. Homework. 5. Hashes and Message Digests. Introduction. Nifty Things to Do with a Hash. MD2. MD4. MD5. SHA-1. HMAC. Homework. 6. Public Key Algorithms. Introduction. Modular Arithmetic. RSA. Diffie-Hellman. Digital Signature Standard (DSS). How Secure Are RSA and Diffie-Hellman? Elliptic Curve Cryptography (ECC). Zero Knowledge Proof Systems. Homework Problems. 7. Number Theory. Introduction. Modular Arithmetic. Primes. Euclid's Algorithm. Chinese Remainder Theorem. Zn. Euler's Totient Function. Euler's Theorem. Homework Problems. 8. Math with AES and Elliptic Curves. Introduction. Notation. Groups. Fields. Mathematics of Rijndael. Elliptic Curve Cryptography. Homework. II. AUTHENTICATION. 9. Overview of Authentication Systems. Password-Based Authentication. Address-Based Authentication. Cryptographic Authentication Protocols. Who Is Being Authenticated? Passwords as Cryptographic Keys. Eavesdropping and Server Database Reading. Trusted Intermediaries. Session Key Establishment. Delegation. Homework. 10. Authentication of People. Passwords. On-Line Password Guessing. Off-Line Password Guessing. How Big Should a Secret Be? Eavesdropping. Passwords and Careless Users. Initial Password Distribution. Authentication Tokens. Physical Access. Biometrics. Homework. 11. Security Handshake Pitfalls. Login Only. Mutual Authentication. Integrity/Encryption for Data. Mediated Authentication (with KDC). Nonce Types. Picking Random Numbers. Performance Considerations. Authentication Protocol Checklist. Homework. 12. Strong Password Protocols. Introduction. Lamport's Hash. Strong Password Protocols. Strong Password Credentials. Strong Password Credentials Download Protocols. Homework. III. STANDARDS. 13. Kerberos V4. Introduction. Tickets and Ticket-Granting Tickets. Configuration. Logging Into the Network. Replicated KDC's. Realms. Interrealm Authentication. Key Version Numbers. Encryption for Privacy and Integrity. Encryption for Integrity Only. Network Layer Addresses in Tickets. Message Formats. Homework. 14. Kerberos V5. ASN.1. Names. Delegation of Rights. Ticket Lifetimes. Key Versions. Making Master Keys in Different Realms Different. Optimizations. Cryptographic Algorithms. Hierarchy of Realms. Evading Password-Guessing Attacks. Key Inside Authenticator. Double TGT Authentication. PKINIT-Public Keys for Users. KDC Database. Kerberos V5 Messages. Homework. 15. PKI (Public Key Infrastructure). Introduction. Some Terminology. PKI Trust Models. Revocation. Directories and PKI. PKIX and X.509. X.509 and PKIX Certificates. Authorization Futures. Homework. 16. Real-time Communication Security. What Layer? Session Key Establishment. Perfect Forward Secrecy. PFS-Foilage. Denial-of-Service/Clogging Protection. Endpoint Identifier Hiding. Live Partner Reassurance. Arranging for Parallel Computation. Session Resumption. Plausible Deniability. Data Stream Protection. Negotiating Crypto Parameters. Easy Homework. Homework. 17. IPsec: AH and ESP. Overview of Ipsec. IP and Ipv6. AH (Authentication Header). ESP (Encapsulating Security Payload). So, Do We Need AH? Comparison of Encodings. Easy Homework. Homework. 18. IPsec: IKE. Photuris. SKIP. History of IKE. IKE Phases. Phase 1 IKE. Phase - 2 IKE: Setting up Ipsec Sas. ISAKMP/IKE Encoding. Homework. 19. SSL/TLS. Introduction. Using TCP. Quick TCP. Quick History. SSL/TLS Basic Protocol. Session Resumption. Computing the Keys. Client Authentication. PKI as Deployed by SSL. Version Numbers. Negotiating Cipher Suites. Negotiating Compression Method. Attacks Fixed in v3. Exportability. Encoding. Further Reading. Easy Homework. Homework. IV. ELECTRONIC MAIL. 20. Electronic Mail Security. Distribution Lists. Store and Forward. Security Services for Electronic Mail. Establishing Keys. Privacy. Authentication of the Source. Message Integrity. Non-Repudiation. Proof of Submission. Proof of Delivery. Message Flow Confidentiality. Anonymity. Containment. Annoying Text Format Issues. Names and Addresses. Verifying When a Message Was Really Sent. Homework. 21. PEM & S/MIME. Introduction. Structure of a PEM Message. Establishing Keys. Some PEM History. PEM Certificate Hierarchy. Certificate Revocation Lists (CRLs). Reformatting Data to Get Through Mailers. General Structure of a PEM Message. Encryption. Source Authentication and Integrity Protection. Multiple Recipients. Bracketing PEM Messages. Forwarding and Enclosures. Unprotected Information. Message Formats. DES-CBC as MIC Doesn't Work. Differences in S/MIME. S/MIME Certificate Hierarchy. Homework. 22. PGP (Pretty Good Privacy). Introduction. Overview. Key Distribution. Efficient Encoding. Certificate and Key Revocation. Signature Types. Your Private Key. Key Rings. Anomalies. Object Formats. V. LEFTOVERS. 23. Firewalls. Packet Filters. Application Level Gateway. Encrypted Tunnels. Comparisons. Why Firewalls Don't Work. Denial-of-Service Attacks. Should Firewalls Go Away? 24. More Security Systems. NetWare V3. NetWare V4. KryptoKnight. DASS/SPX. Lotus Notes Security. DCE Security. Microsoft Windows Security. Network Denial of Service. Clipper. Homework. 25. Web Issues. Introduction. URLs/URIs. HTTP. HTTP Digest Authentication. Cookies. Other Web Security Problems. Homework. 26. Folklore. Perfect Forward Secrecy. Change Keys Periodically. Multiplexing Flows over a Single SA. Use Different Keys in the Two Directions. Use Different Secret Keys for Encryption vs. Integrity Protection. Use Different Keys for Different Purposes. Use Different Keys for Signing vs. Encryption. Have Both Sides Contribute to the Master Key. Don't Let One Side Determine the Key. Hash in a Constant When Hashing a Password. HMAC Rather than Simple MD. Key Expansion. Randomly Chosen Ivs. Use of Nonces in Protocols. Don't Let Encrypted Data Begin with a Constant. Don't Let Encrypted Data Begin with a Predictable Value. Compress Data Before Encrypting It. Don't Do Encryption Only. Avoiding Weak Keys. Minimal vs. Redundant Designs. Overestimate the Size of Key. Hardware Random Number Generators. Timing Attacks. Put Checksums at the End of Data. Forward Compatibility. Negotiating Parameters. Homework. Bibliography. Glossary. Index.

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.

Giovanni Di Crescenzo

No abstract is available for this record.

Claude Crépeau, Jeroen van de Graaf, Alain Tapp

No abstract is available for this record.

Lidong Chen, Ivan Damgård, Torben Pryds Pedersen

No abstract is available for this record.

David Chaum

No abstract is available for this record.

James R. Miller, Ron Goldman

No abstract is available for this record.

James F. Smith

Using the state agencies that regulate wastewater discharges to surface waters, this quantitative study examined the validity of three theories about the effects of decentralization on organizational outcomes. It also used qualitative analysis to probe the internal adjustments to optimize outcomes. Theoretical advantages to decentralized organizations can be summarized as greater effectiveness or greater efficiency. Effectiveness here is the rate of compliance with legal and permit requirements for dischargers adjusted for enforcement actions. The model used consists of decentralization independent variables, exogenous independent variables (e.g., population, funding), efficiency dependent variables, and compliance (or effectiveness) dependent variables. Model calibration applied principal component analysis and multiple regression analysis to questionnaire and other data for FY93 from 39 states. Key intervening variables -- information costs, innovation, and strategic planning -- characteristic of the theoretical effects of decentralization received special attention. Case studies based on interviews and document studies in five states illustrate key points. The large survey sample (78%) of the 50 states reduced threats to external validity. A significant relationship to decentralization was found for major permit processing time and percentage of expired permits. When controlled for exogenous variables, no compliance common factor related to decentralization, but medium-term compliance unit-cost did. Time is essential to all compliance common factors. Innovation, information cost, and strategic planning were not found to be intervening variables. Highly decentralized states were found to be trending towards increased centralization, and vice versa. All states make internal adjustments to optimize their programs, and some adjustments are powerful enough to make highly dissimilar organizations converge; strong basin planning is one such adjustment. Neither decentralization nor centralization is automatically the best way to organize a complex system. Devolution, where transfer of functions goes with significant delegation of authority to autonomous local units, would probably give superior environmental, economic, and administrative outcomes over a uniform approach.

Alfredo De Santis, Tatsuaki Okamoto, Giuseppe Persiano

No abstract is available for this record.

Randall Crane

Abstract Renewed interest by the Indonesian government in decentralization and cost‐recovery practices has led to both real and illusory reforms, though the distinction between the two is often not clear. This is particularly true with respect to infrastructure planning and finance. Recently, the allocation criteria for capital grants to local governments have been substantially revised, nearly every year, to reflect long lasting concerns regarding differences in interregional development needs and resources. In addition, the level of funding for local government investment has risen dramatically to support increased local responsibility in planning. Most development spending does not pass through local budgets, however. In either case, the project planning process has remained firmly under the direction of the central government's technical ministries. Infrastructure investment thus tends to be segmented, not only by sector, but also by funding source. The rate at which these two factors balance off in current practice does not indicate a strong commitment to effective decentralization. The article suggests that greater regional government participation in the national planning process would be beneficial. To deal with the fragmented nature of sectoral planning is more problematic, as a more integrated approach would in the long term require either a new layer of bureaucracy or a substantial reorganization of the technical ministries. In the shorter term, a gradual shift toward general purpose grants would also generate regional development plans more consistent with the goals of decentralization while maintaining substantial central control and oversight.

Ivan Damgård, Oded Goldreich, Tatsuaki Okamoto, Avi Wigderson

No abstract is available for this record.

Linsu Kim Nugent, B Jeffrey

The authors evaluate the effectiveness of private and collective technical, marketing, and financial support systems for the Republic of Korea's small and medium-size enterprises (SMEs) and entrepreneurs. Their report draws on a survey of 122 SMEs that make woven textiles (42 firms), auto parts (20 firms), electronic parts (20 firms), and factory-automation products (40 firms). Although Korea has a dense network of public technology-support institutions, Korean SMEs tend to turn to private sources of technical support (especially from buyers, suppliers, and moonlighting engineers) more often than in public institutions. Even so, some collective support was used often and valued highly, especially in technologically dynamic sectors. For technical assistance to be timely and relevant, its delivery must increasingly be decentralized - to industry-specific institutes and to geographic clusters of SMEs in the same industry. Among various collective providers of technical support for Korean SMEs, at least one was used by more than half of the SMEs surveyed. Collective marketing support was used much less than private sources and was not considered very useful - except by firms in the initial stages of exporting or in the pioneer stage of a new export industry. Generally, networks of local agents and foreign traders developed as firms gained in export experience. Financial assistance is the most critical form of support for SMEs. The Korean government has made extensive use of parastatal finance institutions, target credit, and credit guarantee schemes. Government intervention in finance was so pervasive that the line between private and collective support blurred. Most SMEs sampled used at least one collective institution of financial support, and rated them very positively.

Anthony Grafton, Suzanne Marchand

No abstract is available for this record.

Bobuin John Gemandze

Even though the concept of decentralization has received extensive treatment in the literature, (Maddick,1962; Fesler, 1965; Kaufman, 1969; Laubadere, 1973; Kochen & Deutsch, 1980; Cohen et ale ,1981; Rondinelli,1981; onyers,1983; Smith,1985; Gonidec,1985; Adamolekun et al.1990), there is as yet no consensus as to its precise meaning and content either within academic or professional circles. Rondinelli, (1981), asserts that decentralization is often discussed and proposed by government officials and staffs of international aid agencies without a concise conception of its meaning and without a real understanding of the alternative forms that decentralization can take. According to Cohen et al., (1981), there are a number of activities which parade under the banner of decentralization viz; devolution, deconcentration, delegation to autonomous agencies, delegation to parallel organizations, worker's self-management. On the other hand, Sherwood (1969), argues that devolution is not decentralization. For him, decentralization refers to an intraorganizational pattern of power relationships, whereas devolution involves an interorganizational pattern of power relationships (Sherwood,1969).

Oded Goldreich, Yair Oren

No abstract is available for this record.

Joseph L. Scarpaci, Ignacio Irarrázaval

A major issue in Latin. America is the decentralization of public finances and the autonomy of local government. This article begins with a brief review of the ongoing decentralization debate. We then discuss key features of local government finance and autonomy among unitary and federal governments in Latin America. Against that backdrop, we focus on the Chilean case, which has been a widely celebrated success story in the economic development literature. We argue that despite major gains by municipal governments over the past two decades, financial decision making powers still rest with the national government. This creates financial complacency among local governments. To remedy this, we conclude with six proposals for promoting effective decentralization.