Blockchain Papers

Loretta Napoleoni

This article analyzes the impact of counter-terrorism policies, e.g., the Patriot Act and the war in Iraq, on the financial structure of European terror networks and argues that such policies, far from defeating Jihadist activities, ended up boosting them. In response to such measures, terror finances have been skillfully restructured, the main changes being the decentralization of funding activity in Europe and in the Middle East and the declining cost of terrorist attacks.

Zheng Hu

While the pervasiveness of wireless technology has provided a major impetus to mobile services,challenges the mobility of mobile services much.The characteristics of personal environments:heterogeneity,short distance between devices,and group mobility,are analyzed,and a decentralized directory storage method is proposed based on them for the autonomous organization of devices.It provides proper group mobility support and saves bandwidth,so that,improves the stability of system in personal environments.

David M. Gaba

It is a fact of history that many of us who pioneered simulation in healthcare took as inspiration the experience of other intrinsically high-hazard industries such as commercial aviation. Many of us have argued forcefully that healthcare should adopt simulation comprehensively in part to follow the model set by these industries. Yet, with simulation in healthcare having some roots that go back decades, and with even aviation-inspired curricula in healthcare (like ACRM) approaching 20th anniversaries (ACRM was first offered in September 1990) one can wonder why the healthcare industry has not embraced and implemented simulation as fully as has been done by other industries including commercial aviation, the military, or nuclear power. I would like to explore this analogy a little more deeply, reviewing what I see as the meaningful similarities, as well as the profound differences, between healthcare as an industry and these other risky human endeavors, focusing especially on commercial aviation. This paper is a combination of my own personal recollections and an objective assessment of the industries. Some elements of this analysis are taken from my paper Structures and Organizational Issues in Patient Safety: A Comparison of Health Care to Other High Hazard Industries (California Management Review, Fall, 2000)1 while other aspects come from the talks I have been giving in the last 7 years. The Flight Deck as a Cognitive Parallel for Dynamic Healthcare Settings A little known point about my own laboratory's development of the mannequin-based simulator in the late 1980s was that we started with the goal of creating a tool for the understanding of cognition of anesthesiologists in the handling of adverse events. We were driven to this by our analysis of the “chain of accident evolution” in anesthesia – the ways in which inciting triggers end up as major catastrophes if not interrupted by the intervention of the anesthesiologist. We made a number of conjectures about cognition in these settings: “To recover from anesthesia incidents, the anesthesiologist must: 1) detect one or more of the manifestations of the incident in progress; 2) verify the manifestations and reject false alarms; 3) recognize that the manifestations represent an actual or potential threat; 4) assure continued maintenance of life-sustaining functions; 5) implement “generic” diagnostic or corrective strategies to provide failure compensation and allow continuation of surgery if possible; 6) achieve specific diagnosis and therapy for the underlying causes; and 7) provide follow-up of recovery to ensure adequate correction or compensation.”2 To provide empirical data to confirm these conjectures we needed a way to provide standardized adverse events to different clinicians to tease out the typical response behaviors. My own background as an avowed “aviation and space nut” stood me in good stead, giving me the knowledge of the existence of simulators in these arenas. That led us to create the CASE simulator series initially for this cognition research.3 Our experiments were described in several papers appearing in Anesthesia and Analgesia.4–6 As we looked for models in medicine of such dynamic decision making processes we didn't find them. Most of the literature on medical decision making were about quite static decisions, and concerned highly mathematical and probabilistic techniques that couldn't readily account for the behavior of anesthesiologists that we had observed. But we did find models for such cognition in other industries, particularly aviation. The flight deck of the aircraft does have a number of cognitive parallels with that of anesthesia and other medical domains, such as intensive care or emergency medicine. In all such settings most time will be spent in ordinary and routine activities. Like in the operating room, even in a busy ICU or emergency department the true crises will be rare. Hours of boredom, moments of terror is a mantra on the flight deck as well as in the operating room. A “flight” has many similarities to “an anesthetic.” Each has a phase of preparation – analysis of the situation (weather versus underlying diseases) – and equipment checks. Take off is like induction, cruise is like maintenance, and landing is like emergence. Certain flights, and certain surgical cases have key midstream milestones that must be anticipated and planned for. On both the flight deck and in the operating room there is a plethora of information sources, some of them mutually redundant, requiring dynamic allocation of attention but allowing cross-checking between sources. Our own research had shown that anesthesiologists did not solve acute problems by direct application of deep abstract reasoning but rather by applying “precompiled” knowledge, doing the usual things about the usual problems. Aviation does the same thing except they have codified many of the responses into an emergency procedures manual; pilots are expected to know from memory the first few items of these procedures, but to use the written protocols themselves for anything further. Both commercial flying and healthcare are conducted in crews and teams. We consider a crew to be one or more individuals each from a specific discipline, sometimes with their own hierarchy; multiple crews working together makeup a team. The flight deck crew are pilots (the days of nonpilot flight engineers in a 3 person flight deck are almost gone) with a “Captain” and “First-Officer”. The flight deck crew combine with the cabin crew to make up the aircraft team, and the team is larger still when air traffic control, airline dispatch and maintenance are included. Similarly, the OR has a surgeon crew, a nursing crew, an anesthesia crew, and sometimes specialist technicians (like cardiopulmonary bypass perfusionists). The crews work together as a team. Aviation found that intracrew and intercrew coordination was a major feature of good problem solving and that failures of coordination were at the root of many accidents.7 We also felt, by introspection, that a substantial part of expertise in anesthesiology lay in the ability to coordinate the anesthesia crew members (whenever there was more than one) and in the ability to coordinate with the other crews, especially the surgeons. Given these similarities, it is no wonder that we believed intuitively then, and still do now, that it was worth adapting many practices of aviation for use in healthcare. The use of simulation in aviation has been extensive, both for teaching practical “stick and rudder” skills but since the mid 1980s, also for the so called “nontechnical” skills known as Crew Resource Management (CRM).8,9 Having first heard about CRM possibly in an episode of the PBS show NOVA called “Why Planes Crash” we were fortunate that one key architect of early CRM worked at the nearby NASA Ames Research Center. This contact facilitated our exposure to the CRM approach allowing us to rapidly adapt many elements of CRM into a simulation-based curriculum for anesthesiology (ACRM). The wide spread of the simulation-based CRM approach within anesthesiology and across health care disciplines and domains has been gratifying to watch. Clearly, the resonance that we perceived between the cognitive and social psychologic aspects of work on the flight deck with that in the hospital has been shared by thousands of others. Nearly 20 years down the line in applying aviation concepts to health care, I still stand by the marked parallels at the level of the “sharp end” work itself. The dynamic thinking of people in dynamic fields of health care is much like that of pilots (and where it isn't yet, it probably should be closer). The 2 activities are not the same of course. Patients are not airplanes. Some aspects of health care are intrinsically different from aviation because of this fact. Other aspects are different not because of an intrinsic difference in the work but rather because of differences in the organizational structure of health care as an industry versus air transport as an industry. Let me explore some of each kind of these differences. What Does It Mean That Patients Are Not Airplanes? A major feature of the notion that “patients are not airplanes” is that people don't design and build human beings whereas they do design and build airplanes. I like that say that no one provides the instruction manual for humans. These facts mean that the level of uncertainty about human beings is enormously greater than that about airplanes. Each plane of a given type will behave in nearly the same fashion given the same small set of key characteristics (eg, thrust, weight, altitude, angle of attack) whereas the diversity between human beings is enormous. Designers instrument airplanes to give key data that can be relied on to fly the plane, whereas in health care clinicians typically obtain a smattering of data (eg, blood pressure, ECG, oxygen saturation) from noninvasive external sources. Airplanes are usually in good shape when we fly them, and there aren't mechanics in the back working on the aircraft during a flight, liable to sever a hydraulic line or the like. A daily variable in flying is weather and in this regard has some parallel to the routine diversity of “patient acuity” that we deal with in health care. Still, in commercial flying if the weather is bad enough, the planes don't fly regardless of how badly the passengers need to get where they're going. In health care, if the surgery is important enough it must go ahead regardless of whether the underlying disease state poses a danger. Another consideration is that health care is very personal. Most people don't care who the pilot of their airliner is as long as she or he is good at the job, and we don't care if the same pilot flies us on one leg of our trip as on the next leg. But we do care a lot about our physicians and having a personal relationship with physicians is perceived to be very important. Moreover, health care is full of issues of social norms and ethics that rarely enter into the sphere of aviation. Organizational Differences Between Healthcare and Other Industries Integration and Economies of Scale: Both aviation and health care are extremely decentralized, in contrast to some other high hazard undertakings that have been studied extensively (like aircraft carriers, of which the entire world has only 20, in the hands of but a few nations' navies). Annually in the U.S. there are more than 11 million departures by large airlines and somewhat over 30 million surgical procedures (the actual number is hard to come by), a roughly comparable figure. Both endeavors are conducted at hundreds or thousands of sites scattered all across the nation, some very large, and some relatively small. In this respect the industries are comparable. But whereas only about 10 airlines are responsible for the 11 million flights, the surgical procedures are conducted at (on the order of) 4,000–6,000 hospitals and a similar number of standalone surgicenters (not to mention office-based surgery). These are owned by on the order of 1,000 – 6,000 firms (no one really knows the number of firms; there are some large hospital chains, but most hospitals are one or 2 of a kind). The small number of firms gives airlines a huge economy of scale and it greatly simplifies both official and unofficial safety regulation of the industry. A good safety idea, even if not an official “de jure” regulation, can be adopted by the industry nationwide if 10 firms think it is worth doing. In healthcare one would have to convince each one of the many thousands of firms. There are a few examples of very large integrated health care organizations in the U.S (the Veterans Affairs health system is one and Kaiser Permanente is another; both have had much publicized safety efforts). Whether safety is actually greater in such integrated systems than in any nonintegrated collection of institutions of similar size, diversity, and scope remains to be seen, but it is conceivable that a system with some of the economies of scale and integration like that of the airline industry could come into being and demonstrate safety benefits of such organization. Accidents and the Means of Production The rates of fatal accidents in these industries is markedly disparate. Between 2002 and 2006 there were on the order of 10.5 to 11.5 million departures on major airlines (Part 121– see http://www.ntsb.gov/aviation/Table5.htm) with between 0 to 3 fatal accidents killing 0–50 people (median about 20). This yields rates of fatal crashes on the order of 0.020 per 100,000 departures. In healthcare we do not know the rates of fatal accidents so clearly. An airplane is never supposed to crash, and when it does it is highly public and may harm dozens or hundreds of people. When it comes to health and disease, all humans are destined to die, and in the industrial world nearly all will die in proximity to healthcare activities. Sorting out those that were due to accidents and those that were due only to the natural course of disease is difficult. Further, healthcare accidents are hidden and usually harm only one person. Still if taking the most wildly optimistic estimates of healthcare success – say the rate of fatal accidents due only to anesthesia care for healthy patients having routine surgery, which are on the order of 0.5 deaths per 100,000 cases,10,11 healthcare is still 25 times more dangerous than flying. For healthcare as a whole the gap is probably considerably larger. In aviation and other hazardous industries accidents harm workers and often the public, are highly publicized by the media, generate lawsuits, and (cynically) of even more concern is that a catastrophic accident destroys the means of production. In such a case the airplane (or even worse in the power industry, a power plant) is removed from service and has to be replaced at great cost and disruption. This gives even the hard-hearted “bean-counters” a healthy interest in avoiding accidents. In healthcare by contrast, accidents or other episodes of suboptimal care harm a patient but do not (generally) harm workers or the means of production. When clinicians hurt a patient they may feel bad about it but then they send for the next patient scheduled for that site. The recent announcement by the major U.S. government payer for healthcare (Centers for Medicare and Medicaid Services) that it will no longer pay for certain preventable conditions, mistakes or infections resulting from a hospital stay is a slight step in the direction of greater “business reasons” to avoid accidents, but even so the means of production are left intact. Imagine how much more seriously this would be taken if every time there was a serious problem in care in the OR or ICU that site had to be taken out of service for a year. Regulation In the U.S. a single federal agency regulates air transport, and comprehensively oversees nearly every level of equipment, personnel, and detailed operations all the way down to some flight crew processes. Beyond the official regulator there is a national independent agency (the National Transportation Safety Board) that investigates accidents and makes safety recommendations to the regulatory body. The firms themselves exert strong control over the pilots with standard operating procedures and company policies that are strongly adhered to. In health care, while a federal agency regulates drugs and devices, it does not regulate the practice of medicine. Each of 50 states and 3 federal jurisdictions (Department of of Veterans and the Health regulates the practice of medicine. The level of government regulatory control is and in it is very (or at the level of actual firms only over the practices of There is no independent official safety for health care. There is regulation by like the a level of regulation such is to for for as from government the some healthcare institutions not to be by the and even the of this agency has been in the as being relatively The has more assessment procedures, especially in relatively the hospitals often know in that is in the level of control by such regulation is still rather In some have with somewhat from the perceived by many or to the model of work for The of In this model the hospital like a in which the independent members to do their The did not any level of control over the the have done some hospitals do to safety that to I have been in several such are but the level of organizational and control are and at Many of the organizational in health care come from more than years and some are But the of health care work has greatly in this there was often little harm physicians could do to patients and other of were probably but rarely in and of in many settings the per is quite The of and high medical care may not well to organizational from over the years there has been some of and the of how healthcare is for has the work of physicians is one of the most activities of intrinsically risky human A substantial of and is in the system because human beings are not airplanes or nuclear power Healthcare does not need to achieve the same level of and control that these industries. But the in in my is quite to the other and to a is an important goal on the to safety and and Differences between the industries on the structure and of and are also The major airlines in the U.S. on other systems to flight airlines in the world flight taking pilot from experience and doing all the In the many pilots from the is – pilots working their way up in the then airlines to the in both systems is but it is not so much on the of of underlying knowledge but rather more on the of actual and The airlines have highly to and to their own and is by the and by the government – it can be done in a airliner or in a the simulator is a and On of this is a of assessment of pilots by the government both during and during actual Healthcare at the level of on and but not on for the by a long of of concepts and then by an of or taking care of patients of) What one on which patients in the during and the of the specific members as When very or crises the are out of the way so that can the There is little with of with a (and of for physicians the can be by a wide diversity of few of them or on issues of or patient These differences, like most of the other organizational differences are not intrinsic to the fact that patients are not airplanes. Healthcare could use the same of and to assure the and of The is a of and not the or consideration of how to achieve the by some the healthcare system could be from it would probably be and it much more like some of the other high-hazard industries. In I sometimes wonder – thinking about my own of anesthesiology – whether things would have been different had flight been in and anesthesia only in rather than the other way it isn't to the healthcare system from first must be made while the and organizational elements of the system intact. This is one of the key to the processes of simulation-based and assessment we in aviation. has been made in the last years from such industries, but it will the of this approach are fully in healthcare. of this will be in this but I have over more than 20 years that we had have a lot of and a long in

Ling Cheung, Sayan Mitra, Olivier Pereira

Abstract. Statistical zero-knowledge (SZK) properties play an important role in designing cryptographic protocols that enforce honest behavior while maintaining privacy. This paper presents a novel approach for verifying SZK properties, using recently developed techniques based on approximate simulation relations. We formulate statistical indistinguishability as an implementation relation in the Task-PIOA framework, which allows us to express computational restrictions. The implementation relation is then proven using approximate simulation relations. This technique separates proof obligations into two categories: those requiring probabilistic reasoning, as well as those that do not. The latter is a good candidate for mechanization. We illustrate the general method by verifying the SZK property of the well-known identification protocol proposed by Girault, Poupard and Stern. ⋆ Supported by the MURI project:DARPA/AFOSR MURI F49620-02-1-0325 grant. 1

Qiao Tong-xu

This paper first analyzes risks of current business related to bank cards,the proposes a new scheme for designing bank card based on zero-knowledge proof and-finally technical system,security and possible applications of the scheme are discussed.

Pingshui Wang

Zero-knowledge proof has been one of the key technologies to be applied in identity authentication in the fields of information security.To avoid the use of the graph isomorphism problem in the known zero-knowledge proof systems,an efficient computational zero-knowledge proof of knowledge whose security relies on the NP-Completeness of the independent set problem is presented here.The proposed logarithm is constructed from a bit commitment scheme based on the hardness of the discrete logarithm problem,which guarantees the fulfillment of soundness,completeness and computational zero-knowledge properties.The system and its logarithm parameter choice were analyzed from two aspects of computational complexity and communication complexity.It was proved theoretically that the system is feasible and effective.

Zhu Hongwu

By imitating the zero-knowledge proof protocol of RSA digital signature,we get a faulty zero-knowledge proof protocol of EIGamal digital signature.And this paper will analyze it.

Douglas R. Stinson, Jiang Wu

In this paper, we propose a zero-knowledge authenticated key agreement protocol with key confirmation (AKC) in asymmetric setting. The protocol has several desirable security attributes like some classical AKCs such as STS [7] and MQV [13]. One highlight of our protocol is its zero-knowledge property, which enables succinct proofs of the claimed security attributes, while the overhead in communication and computation resulting from the special design to achieve zero-knowledge is insignificant.

Mireille Hildebrandt

This article explores the complex relationship between law and (scientific) expertise. The author first discusses the difference between scientific knowledge and scientific expertise, tracing the historical roots of the concept of proof in a legal rather than a mathematical context. Second, the historical roots of the fair trial are discussed in terms of the premodern épreuve and the modern preuve, demonstrating the relationship with coordinate and subordinate types of justice. Third, Foucault's analysis of épreuve, enquête, and examèn is extended to clarify how preuve and épreuve have been integrated into the fair trial, which is explained in relation to the formal and the substantive notions of the "Rechtsstaat." This analysis finally allows the author to discuss the difference between two approaches of scientific expertise in court: one claiming that judges should defer to science and another claiming that a court of law is one of the spaces in which such expertise can be contested. The article concludes that the integration of subordinate and coordinate justice exemplified in the fair trial, opens new perspectives for the testing of scientific expertise, taking into account whose interests are at stake.

Alia Ahmad, M Bose, Therése Persson

Bangladesh has made significant progress in health indicators in recent years in spite of her low level of income. This is mainly due to the commitment of the state supported by donors in providing preventive care with respect to child health and family planning. However, there are serious problems related to both access and quality of curative care that hurt the poor most. Infrastructures for service delivery exist at local level in rural areas but they function inefficiently. This paper deals with the systemic weaknesses of decentralized service provision of primary healthcare in Bangladesh and focuses on accountability links between different actors and functions of delegation, finance, performance, information and enforcement. The study is based on facility- and household-based data collected during 2005 in Khulna Division. The main findings of the study are: the health system in rural areas represents deconcentration rather than decentralization of central government functions where inter-sectoral discipline works poorly; local health providers are not accountable to local government, and poor citizens/clients are neither aware of their rights nor are capable of expressing their needs as effective channels do not exist.

Hrvoje Šimović

Development of the European integration through the European Union (EU) considers not only strengthening integration from the economic aspect (internal market). It also considers the political aspect of the integration i.e. strengthening political integration of member states and their citizens. Political segment of integration considers strengthening of the internal policies of the EU in which fiscal system, i.e. public finances have extremely important role. The EU fiscal system presents reflection of the extremely strong and often confronted interests between the economic and the political integration. These issues are closely related to the second component of the European politic and economic integration, that are the fiscal relations between the EU “central” level and the national “lower” levels which bring the all important decisions in the EU. According to the theory of public finance (fiscal federalism) and the criteria of economic efficiency, fiscal functions (allocation, redistribution, stabilization) and activities are assigned to the different levels of government, as well as certain resources for their financing. On the basis of fiscal functions carried out by national levels in the EU, and the manner of their financing, the EU is a prominently fiscally decentralized complex community. The traditional approach to the fiscal federalism that fiscal authorities are transferred from central to lover levels means that this is a process of decentralization, while in the case of the EU this means centralization of fiscal authorities from the level on national states to the EU as a supra-national level. The main goal of this paper is to analyze fiscal relations in the EU according to basic fiscal functions: allocation, redistribution and stabilization. Methodology would include analysis and comparison of positive EU aspect with normative aspect of public finances in multi-level community. Induction of gained results will confirm thesis that, because of political restraints, development of common (central) system of the EU public finances is based on alternative approaches of harmonization and cooperation.

Rudolf Barczi

No abstract is available for this record.

Pingshui Wang

Digital signature has been a basal means of identity authentication in era of network information.To improve the security of the digital signature schemes based on zero-knowledge proof technology,the problem of signature forgery by the signer in digital signature schemes based on the zero-knowledge concept is studied,the potential problem of these schemes are analyzed,a modified scheme for obtaining against such forgery without any increase of computation complexity is proposed,the feasibility,security and computation complexity of the modified scheme is concretely analyzed.

Yun Shi

No abstract is available for this record.

Salil Vadhan, Shien Jin Ong

Zero-knowledge protocols enable one party, called the prover, to another party, called the verifier, the validity of a mathematical statement such that the verifier other than the fact that the proven statement is true. The different ways of formulating the terms convince and learns nothing give rise to four classes of languages having zero-knowledge protocols, which are: statistical zero-knowledge proof systems, computational zero-knowledge proof systems, statistical zero-knowledge argument systems, and computational zero-knowledge argument systems. We establish complexity-theoretic characterizations of these four zero-knowledge complexity classes, of which our characterizations for argument systems are novel. Using these characterizations, we show that for languages in NP, the following hold. (1) Instance-dependent commitment schemes are necessary and sufficient for zero-knowledge protocols. Instance-dependent commitment schemes for a given language are commitment schemes that can depend on the instance of the language, and where the hiding and binding properties are required to hold only on the YES and NO instances of the language, respectively. (2) Computational zero knowledge and computational soundness (a property held by argument systems) are symmetric properties. Namely, we show that the class of languages in NP ∩ co-NP having zero-knowledge arguments is closed under complement, and that a language in NP has a statistical zero-knowledge argument system if and only if its complement has a computational zero-knowledge proof system. (3) Any zero-knowledge argument system that is only guaranteed to be secure against the honest verifier that follows the prescribed protocol can be transformed into one that is secure against malicious verifiers that can deviate from the protocol. In addition, our transformation gives us zero-knowledge argument systems with desirable properties like public coins, perfect completeness, a black-box simulator, and an efficient prover. The novelty of our results above is that they are unconditional, meaning that they do not rely on any unproven complexity assumptions such as the existence of one-way functions. Moreover, in establishing our complexity-theoretic characterizations, we give the first construction of statistical zero-knowledge argument systems for all of NP based on any one-way function.

Gao Ji-zhong

Zero-knowledge proof is a protocol, and ElGamal's digital signature is widely applied. Gives a GMR module of zero-knowledge proof about ElGamal's digital signature which has little computation, high reliability, and easy to implement.

Jean-Philippe Fontenelle, François Molle, Hugh Turral

The political changes which induced the technical and institutional evolution of the Red River Delta's (Vietnam) water control systems are described. The management framework and financial organization of the delta's water control systems are also described. The financing of the different operators, the amount and use of the water fees paid by farmers, and the process of water management decentralization and privatization in the delta, are analysed.

James W. Fossett

Managing Reproductive Pluralism: The Case for Decentralized Governance James W. Fossett (bio) When bioethicists look for solutions to complex problems, they tend to look for single standards and national institutions. Both liberal and conservative bioethicists have pressed for national standards administered by federal agencies across a wide variety of issues ranging from research ethics and assisted reproduction to the governance and financing of stem cell research. Nowhere is this bias clearer than in discussions of reproductive issues, broadly defined. Fukuyama and Furger’s report is only the latest in a long series of proposals that call for a national reproductive policy similar to that managed in the United Kingdom by the British Human Fertilization and Embryology Authority (HFEA). A single set of national rules governing reproductive matters, it has been widely argued, would provide for greater administrative efficiency, consistency, and quality of services, and avoid the “patchwork” of oversight by professional groups, sporadic state regulation, and significant deference to individual consumer choice that typifies current governance of reproduction. In fact, any attempt to set national reproductive policy, no matter how reasonable its bioethical premises, is both politically unachievable and substantively unwise. The inability of the national government to establish a coherent reproductive policy is not the result of “political failure,” as Fukuyama and Furger would have it, but rather of profound disagreement among members of the general public, advocacy groups, policy-makers, and bioethicists about the moral status of the embryo, the right of women to control their own bodies, the appropriateness [End Page 20] of selling oocytes and of federal funding for stem cell research, the utility of state regulation of medical practice, and a variety of other complex and controversial issues that a national reproductive policy would have to address. Given the extreme diversity of views about these issues, enactment of any coherent national reproductive policy seems unlikely. Attempts to force a national consensus where none now exists are almost certain to fail; worse, they will waste precious time on the national agenda without resolving the ethical dilemmas that currently divide us. The existing decentralized decision-making structure for public bioethical issues allows for multiple outcomes and better represents our conflicting and diverse views about reproduction. Federal Deadlock A national regulatory scheme for reproductive matters is likelier to succeed in countries that, like the United Kingdom, view health care as a public commodity and have a tradition of national control over it. Patients and providers in these countries accept government regulation of virtually every kind of health care issue. In the United States, however, health care is a market commodity, and self-regulation of the practice of medicine is a longstanding tradition. With the exception of quality control regulation (which bears on the licensing of providers and oversight of drugs, devices, and research), the market and professional societies regulate medical practice. Both public and professional groups have issued guidelines for the treatment of particular conditions, but adherence to these guidelines is not compulsory. Against this status quo, the creation of an “ethics police” to regulate any part of medicine—but especially reproductive medicine, which inherently raises controversial and divisive issues—would be such a dramatic change that it would probably fail politically. Such a proposal would attract considerable opposition, and not only from those who provide reproductive medicine. Organized medical groups outside reproductive medicine but fearful of any precedent for federal control over the details of medical practice would join the opposition. So, too, would patients who fear that their access to services would be limited. Even if passed, federal rules restricting such practices as the purchase of eggs for reproductive purposes, the number of embryos that can be implanted in each reproductive cycle, or the use of preimplantation genetic diagnosis would almost certainly be subject to repeated legal challenges. The American constitutional and administrative law frameworks are more favorable to such challenges than those of other countries, making it at least possible, if not likely, that significant features of a reproductive regulatory scheme would be overturned or substantially modified by judicial action. Some of the specific features of such a regulatory scheme are also likely to attract controversy. Pro-life and prochoice groups alike are certain to...

James A. Reggia, Alejandro Rodríguez

In recent years researchers have shown increasing interest in swarm intelligence as a promising approach to adaptive distributed problem solving. Swarm intelligence consists of techniques inspired by nature, especially social insects and aggregations of animals, and even human interactions. They are based on self-organization (a system's overall behavior emerges from the local interactions among its relatively simple components) and are often decentralized and massively distributed. Particle systems are an approach to swarm intelligence that focus on collective movements, and have been used successfully for applications such as computer animation in graphics and control of movements of autonomous robotic vehicle teams. However, particle system techniques have not been applied substantially to problem solving beyond merely collective navigational tasks. In this dissertation, I present an extension to particle systems that incorporates top-down, high-level control to self-organizing mobile agents, thereby guiding the self-organizing process and making it possible for particle systems to undertake problem solving directed by goal-oriented behavior while retaining their decentralized, local nature. This extended particle system approach is critically evaluated through three experimental studies that are adapted from well-known problems in multi-agent systems: search and collect, cooperative transport and logistics. The results provide evidence that extended particle systems are capable of exhibiting behavior important for distributed problem solving, such as cooperative sensing, division of labor, sharing of information, and developing global strategies through local interactions. They also show that aggregated movements can be utilized to create coordination at different levels and phases of the performance of a task, whether those include navigation or not, making extended particle systems a useful tool in the construction of adaptive distributed systems.

Jeanne W. Ross, Cynthia Mathis Beath

No abstract is available for this record.

Dragos Florin Ciocan, Salil Vadhan

We show that a problem in AM has a interactive zero-knowledge proof system if and only if it has a noninteractive zero knowledge proof system in the ‘help model’ of Ben-Or and Gutfreund (J. Cryptology, 2003). In this model, the shared reference string is generated by a probabilistic polynomial-time dealer who is given access to the statement to be proven. Our result holds for both computational zero knowledge and statistical zero knowledge, and does not rely on any unproven complexity assumptions. We also show that help does not add power to interactive computational zero-knowledge proofs, paralleling a result of Ben-Or and Gutfreund for the case of statistical zero knowledge.

Omrane Guedhami, Jeffrey Pittman

No abstract is available for this record.

Jochen Gläser

This chapter contributes to the sociological understanding of open source software (OSS) production by identifying the social mechanism that creates social order in OSS communities. OSS communities are identified as production communities whose mode of production employs autonomous decentralized decision making on contributions and autonomous production of contributions while maintaining the necessary order by adjustment to the common subject matter of work. Thus, OSS communities belong to the same type of collective production system as scientific communities. Both consist of members who not only work on a common product, but are also aware of this collective work and adjust their actions accordingly. Membership is based on the self-perception of working with the community’s subject matter (software or respectively scientific knowledge). The major differences between the two are due to the different subject matters of work. Production communities are compared to the previously known collective production systems, namely, markets, organizations, and networks. They have a competitive advantage in the production under complete uncertainty, that is, when neither the nature of a problem, nor the way in which it can be solved, nor the skills required for its solution are known in advance.Request access from your librarian to read this chapter's full text.

Oluwafemi Ajayi, Richard Sinnott, Anthony Stell

Access control in decentralised collaborative systems present huge challenges especially where many autonomous entities including organizations, humans, software agents from different security domains seek to access and share resources in a secure and controlled way. Automated trust negotiation (ATN) is one approach that has been proposed for trust discovery and realisation, which enables entities viz. strangers to access resources across autonomous boundaries through iterative exchange of credentials. Various negotiation strategies have been proposed to protect credential disclosure during trust negotiations. However in some domains such as e-health, not all entities are willing to negotiate credentials or disclose access policies directly to strangers regardless of negotiation strategies and instead prefer to negotiate and disclose sensitive information only to strangers within what we refer to as a circle of trust. In this paper, we introduce a formal model to describe how locally trusted intermediary parties can provide multiple negotiation and delegations hops to protect credentials and access policies. We propose a dynamic trust negotiations (DTN) model that not only protects sensitive information from disclosure but also reduces semantic issues that exist with credentials in decentralized systems. This work is currently being explored and implemented within the e-health domain: specifically in the MRC-funded Virtual Organisation for Trials of Epidemiological Studies (VOTES) project