Raziel combines secure multi-party computation and proof-carrying code to provide privacy, correctness and verifiability guarantees for smart contracts on blockchains. Effectively solving DAO and Gyges attacks, this paper describes an implementation and presents examples to demonstrate its practical viability (e.g., private and verifiable crowdfundings and investment funds). Additionally, we show how to use Zero-Knowledge Proofs of Proofs (i.e., Proof-Carrying Code certificates) to prove the validity of smart contracts to third parties before their execution without revealing anything else. Finally, we show how miners could get rewarded for generating pre-processing data for secure multi-party computation.
As an emerging decentralized architecture and distributed computing paradigm underlying Bitcoin and other cryptocurrencies, blockchain has attracted intensive attention in both research and applications in recent years. The key advantage of this technology lies in the fact that it enables the establishment of secured, trusted, and decentralized autonomous ecosystems for various scenarios, especially for better usage of the legacy devices, infrastructure, and resources. In this paper, we presented a systematic investigation of blockchain and cryptocurrencies. Related fundamental rationales, technical advantages, existing and potential ecosystems of Bitcoin and other cryptocurrencies are discussed, and a six-layer reference model of the blockchain framework is proposed with detailed description for each of its six layers. Potential applications of blockchain and cryptocurrencies are also addressed. Our aim here is to provide guidance and reference for future research along this promising and important direction.
Regional financial management is better when government supported with capability of adequate regional financial, so itâs can impact on improving services and community welfare. The government can do it, if government spending on services and community welfare, in the form of capital expenditure should get a relatively large portion. The purpose of this study is to determine the effect of regional financial performance to the allocation of capital expenditure. This research was conducted in all regency Province of Bali for the period of 2012-2016. The results of this study indicate that local financial performance as measured by the degree of fiscal decentralization ratio, regional financial independence, SiLPA financing rate, and the degree of BUMD contribution have a positive influence significantly to the allocation of capital expenditure. Meanwhile, the regional financial performance as measured by the ratio of the effectiveness of regional revenue, the efficiency of regional finance have a negative influance not significantly to the allocation of capital expenditure. Keywords: regional financial management, regional financial performance, capital expenditure
Regulators in many countries, including India, view cryptocurrencies as a combination of a bubble and a Ponzi scheme. The Reserve Bank of India has taken steps to dissuade Indian citizens from dealing in cryptocurrencies. However, last yearâs surge in the price of cryptocurrencies has lured many taxpayers into investing or trading in it. Not only is a tussle relating to the fate of cryptocurrencies in India pending before the Indian Supreme Court, the income tax implications of cryptocurrencies are also looming. This article analyses the plausible income tax implications of dealing in cryptocurrencies in India.
This paper presents a distributed Load Balancing Trade Framework (LBTF) with focus on demand response and Advanced Metering Infrastructure (AMI) security in smart grid. This comprehensive energy market model LBTF framework can achieve good balance in demand response in two ways. First way is utility-grid contract, which introduced a simple reward policy using distributed proof-of-work (PoW) consensus algorithm in Blockchain to motivate consumer to use less energy in peak hours. Through this policy consensus algorithm reward electric units to the consumers in peak hours. And in second way scheme introduce Micro-grid contract, which is a peer to peer (P2P) trade in global market. Those consumer (prosumer) who can generate energy using renewable resources can sell their surplus energy to other consumer through this contract. Furthermore, hash functions, public key encryption and digital signatures have been used to provide privacy preserving to the consumers and integrity to the stored data.
In a country like Ghana where Tilapia is the most preferred and cheapest source of animal protein, closer attention must be paid to the supply chain of such a product. This paper examines the major issues and problems in Tilapia supply chain and logistics in Ghana, and it suggests the intervention of the new and disruptive technology of blockchain. Blockchain technology can have the potential to revolutionize the supply chain of Tilapia in Ghana and bring many advantages to the flow of Tilapia from farmers till the end consumers. Besides, it highlights the role of blockchain in ensuring food safety and in rebuilding a trustful network of Tilapia distribution between producers and customers. A model of Tilapia supply chain based on blockchain technology will be exhibited and explained to provide relative solutions to supply chain management processes of Tilapia.
With the increasing of using workflow management systems workflow improvement becomes a new emerging problem. Many issues must be considered to handle all aspects of the workflow improvement. Workflows might become quite complex, especially when we move to Web3 (ubiquitous computing web). Workflows from different domains (e.g., scientific or business) have similarities and, more important, differences between themselves. Some concepts and solutions developed in one domain may be readily applicable to the other. In ubiquitous computing, multi-domain workflow data analysis might cause Big Data challenge. This paper investigates the problem of workflow improvement having an observed behavior (i.e., event logs). It proposes a cross-domain concept extraction by similarity assessment to solve some aspects of workflow improvement problem, and it has a new research effort at the intersection of workflow domains. Besides, the proposed technique is evaluated with the benefit of using Deep learning and Transfer learning. One of the greatest assets to use these both learning methods is analyzing a massive amount of data. Our results show that our proposed technique is effectively applicable for analyzing real-life huge data in workflow improvement.
Zihao Ye, Mengtian Yin, Llewellyn Tang, Jiang Haobo
Cup-of-Water Theory: A Review on the Interaction of BIM, IoT and Blockchain During the Whole Building Lifecycle Zihao Ye, Mengtian Yin, Llewellyn Tang and Haobo Jiang Pages 478-486 (2018 Proceedings of the 35th ISARC, Berlin, Germany, ISBN 978-3-00-060855-1, ISSN 2413-5844) Abstract: The Architecture Engineering and Construction/ Facility Management (AEC/FM) industry plays a significant role in the development of economy. In recent years, the wide application and development of Building Information Modelling (BIM) promote the development of informatization and digitalization of AEC/FM industry. However, due to the limitation of a one single tool and lack of understanding of single source of truth, the problems of the industry cannot be solved completely. Therefore, the revolution and innovation of industry can be stagnated. Internet of Thing (IoT) and blockchain can be considered as two technologies that can be integrated with BIM for AEC/FM industry. The aim of this paper is to understand and analyse the basic principles and the applications of these three technologies in AEC/FM industry through literature review. With the integration of these three technologies, the virtual and realistic object and data during the whole building lifecycle can be managed and stored in a security, transparency and convenient decentralized common data environment (DCDE). Finally, a theory named, Cup-of-Water theory is presented. Keywords: BIM IoT blockchain AEC/FM industry whole building lifecycle DOI: https://doi.org/10.22260/ISARC2018/0066 Download fulltext Download BibTex Download Endnote (RIS) TeX Import to Mendeley
Battleships is a well known traditional board game for two players which dates from World War I. Though, the game has several digital version implementations, they are affected by similar major drawbacks such as fairness and a trust model that relies on third party. In this paper, we demonstrate how to implement a fair, resistant to denial-of-service, where the honest winner earns the deposit money {\em immediately}. The game is built on a permissionless Blockchain that supports Turing complete smart-contract computation.
Andreas GrĂźner, Alexander MĂźhle, Christoph Meinel
The ubiquitous application of emerging blockchain technology in numerous technological projects leads to a tremendous hype. The significantly high prices of digital currencies and initial coin offerings as the new funding approach has fostered the public perception of blockchain as a cure-all and driven the hype even further. In this evolution, a clear view of the reasonable application of blockchain technology is not given and therefore, the purposeful use of traditional technologies is undermined. To clarify this situation, we derive a novel decision model for evaluating the applicability of blockchain technology that considers two key factors: the remediation of central governance and the management of digital objects. Based on these key factors, we closely analyse the domain of identity management for conscious blockchain application. Finally, we examine uPort, Sovrin, and ShoCard as distinct projects in this scope with regard to the inevitable necessity to implement a blockchain by using our decision model.
Emmanouil Platanakis, Charles Sutcliffe, Andrew Urquhart
This paper contributes to the literature on cryptocurrencies by examining the performance of naĂŻve (1/N) and optimal (Markowitz) diversification in a portfolio of four popular cryptocurrencies. We employ weekly data with weekly rebalancing and show there is very little to select between naĂŻve diversification and optimal diversification. Our results hold for different levels of risk-aversion and an alternative estimation window.
Blockchain Report 2018 Blockchain Report UG/Campus Fryslân, Data Research Centre and Globalisation Studies Groningen organised a Blockchain4SDGs interdisciplinary workshop that brought together experts from the development and humanitarian sectors with experts on blockchain technology. Participants jointly explored the implications of blockchain â both its possibilities and limitations â in the field of development and humanitarian action and discussed how the technology could be used to address the United Nationsâ Sustainable Development Goals (UN SDGs). This report presents the results of those discussions. After an introduction to blockchain technology in the fields of humanitarian and development aid, the report summarizes the individual participantsâ contributions to the Blockchain4SDGs workshop. These contributions range from practise examples to theoretical and technological developments. The report also includes summaries of the themes raised during the roundtable discussions and final remarks.
This article demonstrates the pre-eminent position which the term oikonomia (household management) occupied in the first few centuries of Christian theology, opening up avenues which have been left virtually unexplored by modern management scientists. This first level of analysis reveals that the essence of management is inevitably associated with the concepts of non-power, burden and weakness. I then pursue this line of inquiry to look at the role occupied by the notion of âweaknessâ in the postmodern theology developed by Gianni Vattimo and John Caputo, before extending the scope of this analysis to contemporary debates in the field of organization studies, revealing an entirely different vision of the figure of âmanagerâ from that championed in post-Taylorian âscientificâ management, with its emphasis on the behavioural and technical aspects of her/his role. The article concludes by looking at the theoretical and practical implications of âweakâ management.
Now this day we see many new innovations in Monetary System. Now at one side Digital Currency comes with a new concept called Plastic Money with great and easy ways to pay and get money to anyone. And the other side we still struggling with Fiat Currencies problems which effecting economy of any country very badly. Conventional currency has been based on gold or silver. Around the world, people are using software programs that follow a mathematical formula to produce Bitcoins but bitcoin is equally facing risks, non acceptability of central banking system in developing Nations. This paper studies the present scenario of Bitcoin, its evolution and its impact on developing Nations like India
Swathi Singh, R. Suguna, Divya Satish, M. V. Ranjith Kumar
The paper gives an insight on cryptography within digital money used in electronic commerce. The combination of digital currencies with cryptography is named as cryptocurrencies or cryptocoins. Though this technique came into existence years ago, it is bound to have a great future due to its flexibility and very less or nil transaction costs. The concept of cryptocurrency is not new in digital world and is already gaining subtle importance in electronic commerce market. This technology can bring down various risks that may have occurred in usage of physical currencies. The transaction of cryptocurrencies are protected with strong cryptographic hash functions that ensure the safe sending and receiving of assets within the transaction chain or blockchain in a Peer-to-Peer network. The paper discusses the merits and demerits of this technology with a wide range of applications that use cryptocurrency.
Just over twenty years ago, in 1998, science fiction writer and technologist David Brin warned, âOne of the scariest predictions now circulating is that we are about to leave the era of photographic proof. . . . We are fast reaching the point where expertly controlled computers can adjust an image, pixel by microscopic pixel, and not leave a clue behind.â (David Brin, The Transparent Society: Will Technology Force Us to Choose Between Privacy and Freedom? 28 (1998)). Now, many articles are reporting that a similar technological transformation is occurring in the realm of audio- and video recording. Legislators and legal scholars have begun asking what laws or technological measures can be used to protect the public from being deceived by âdeep fakeâ videos.
This symposium essay considers how First Amendment free speech protection might apply to the creation of such videos â and how such protection might differ from the protection that the Supreme Court found, in 2012, applies to false statements of fact. First, it analyzes how courts have generally adhered to a well-established dichotomy in First Amendment treatment of false claims: In the commercial marketplace, government often stands ready to intervene to protect us against being sold forgeries or other fake goods. The same is true in certain situations where security is at stake, for example, where a fake ID might give a person unwarranted access to an airplane or a building off-limits to the general public. Matters are very different, by contrast in the marketplace of ideas. Here, individuals are largely on their own. Government may not constitutionally exile certain ideas from the free trade in ideas, as it can ban harmful goods or services from the realm of buying and selling. In the realm of free expression, wrote Justice Jackson, âevery person must be his own watchman for truth, because the forefathers did not trust any government to separate the true from the false for us.â Thomas v. Collins, 323 U.S. 516 (1945) (Jackson, J concurring). The justices in the 2012 case, United States v. Alvarez, disagreed about how to classify verifiably false autobiographical statement in this dichotomy (and thus disagreed about how to analyze Alvarezâs false claim to have won a Congressional medal of honor). But they largely agreed that false statements on matters of public concern should generally be treated as contributions to the marketplace of ideas, and receive staunch First Amendment protection â unless they constitute defamation, fraud, or some other legally-cognizable harm.
Having examined the Alvarez decision and certain difficulties that confront it, the essay then asks whether this First Amendment framework requires modification when the vehicle for deception is not merely a falsity but a forgery â that is, where it is not merely the content of the speech that is intended to deceive, but also its purported source or vehicle. A deep fake video, for example, does not simply present a false description of an event. It clothes such falsity in the authority of video evidence. The essay considers some of the reasons why the First Amendment should perhaps give government greater leeway to regulate fake video- or audio-recording than verbal lies - why, for example, a false statement about war-time actions might be protected speech, whereas a fake video of an event in that war allowing people to see with their own eyes, events which never occurred - might raise more significant concerns. Or why the false content in a fake news article may be protected speech but this may not be true of the false guise it wears as a New York Times, Chicago Tribune, or Washington Post article when neither publication played any role in it. The essay also briefly considers some of the difficulties that courts would face in attempting to differentiate in this way between falsity and forgery, and providing different First Amendment rules to each category of deception.
The atomic swap protocol allows for the exchange of cryptocurrencies on different blockchains without the need to trust a third-party. However, market participants who desire to hold derivative assets such as options or futures would also benefit from trustless exchange. In this paper I propose the atomic swaption, which extends the atomic swap to allow for such exchanges. Crucially, atomic swaptions do not require the use of oracles. I also introduce the margin contract, which provides the ability to create leveraged and short positions. Lastly, I discuss how atomic swaptions may be routed on the Lightning Network.
Florentin Guth, Valentin WĂźstholz, Maria Christakis, PĂŠter MĂźller
Smart contracts are programs that manage digital assets according to a certain protocol, expressing for instance the rules of an auction. Understanding the possible behaviors of a smart contract is difficult, which complicates development, auditing, and the post-mortem analysis of attacks. This paper presents the first specification mining technique for smart contracts. Our technique extracts the possible behaviors of smart contracts from contract executions recorded on a blockchain and expresses them as finite automata. A novel dependency analysis allows us to separate independent interactions with a contract. Our technique tunes the abstractions for the automata construction automatically based on configurable metrics, for instance, to maximize readability or precision. We implemented our technique for the Ethereum blockchain and evaluated its usability on several real-world contracts.