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Jul 18, 2017¡Economics and Law
0 cites
ECONOMIC AND LEGAL FRAMEWORK FOR DECENTRALIZATION IN UKRAINE

V.A. Ustymenko

The article is devoted to the legal aspects of decentralization in Ukraine, the problems arising in the creation and functioning of the united territorial communities. The mechanism of solving the problems facing the united territorial commu nities with the help of public-private partnership is proposed. It is proposed to make wider use of the advantages of economic and legal experiments. REFERENCES1. The Cabinet of Ministers of Ukraine (2014), Koncepciya reformuvannya miscevogo samovryaduvannya ta terytorialnoyi organizaciyi vlady v Ukrayini, zatverdzhena Rozporyadzhennyam [The concept of local government reform and territorial organization of power in Ukraine, approved by Decree], Oficijnyj visnyk Ukrayiny, vol. 30, art. 831.2. The Verkhovna Rada of Ukraine (2014), Pro spivrobitnycztvo terytorialnyh gromad : Zakon Ukrayiny [On cooperation of local communities: The Law of Ukraine], Vidomosti Verhovnoyi Rady Ukrayiny, vol. 34, art. 1167.3. The Verkhovna Rada of Ukraine (2015), Pro dobrovilne ob’yednannya terytorialnyx gromad : Zakon Ukrayiny [On a voluntary association of local communities: The Law of Ukraine], Vidomosti Verhovnoyi Rady Ukrayiny, vol. 13, art. 91.4. Tkachuk A. (2017), O decentralizacii, uspehah, riskah i roli parlamenta [On Decentralization, Progress, Risks and the Role of Parliament], Zerkalo nedeli, available at: http://gazeta.zn.ua/internal/o-decentralizacii-uspehahriskah-i-roli-parlamenta-_.html5. The Verkhovna Rada of Ukraine (2015), Pro zasady derzhavnoyi regionalnoyi polityky : Zakon Ukrayiny [OnPrinciples of regional policy: The Law of Ukraine], Vidomosti Verhovnoyi Rady Ukrayiny, vol. 13, art. 90.6. The Verkhovna Rada of Ukraine (2010), Byudzhetnyj kodeks Ukrayiny [The Budget Code of Ukraine], Vidomosti Verhovnoyi Rady Ukrayiny, vol. 50—51, art. 572.7. Jakel’ R. (2017), Nu pochti realistichnyj bjudzhet [Well, almost a realistic budget], Zerkalo nedeli, available at: http://gazeta.zn.ua/economics_of_regions/nu-pochtirealistichnyy-byudzhet-_.html8. Slobozhan A. (2013), Mestnoe samoupravlenie i evroperspektivy [Local self-government and Euro-perspectives], Zerkalo nedeli, available at: http://gazeta.zn.ua/macrolevel/mestnoe-samoupravlenie-i-evroperspektivy-_.html9. Derkach M.I. and Lytvyn M.V. (2012), Dosvid Nimechchyny u finansuvanni ekonomichnogo rozvytku regioniv [German experience in financing economic development], BiznesInform, vol. 9, pp. 42—47.10. The Verkhovna Rada of Ukraine (1997), Pro misceve samovryaduvannya v Ukrayini : Zakon Ukrayiny [On local government in Ukraine: The Law of Ukraine], Vidomosti Verhovnoyi Rady Ukrayiny, vol. 24, art. 170.11. The Verkhovna Rada of Ukraine (2003), Hospodars’kyy kodeks Ukrayiny [Economic Code of Ukraine], Ofitsiynyy visnyk Ukrayiny, vol. 11, art. 462.12. Ruchkina G.F. and Kupyzin V.V. (2010), Social’naja otvet stvennost’ sub’ektov predprinimatel’skoj dejatel’nosti i pravovoe regulirovanie otnoshenij po raspredeleniju pribyli [Social responsibility of subjects of entrepreneurial activity and legal regulation of relations on distribution of profit], Predprinimatel’skoe pravo, vol. 1, pp. 35—40.13. The Cabinet of Ministers of Ukraine (2011), Pro zatverdzhennya Metodyky vyyavlennya ryzykiv zdijsnennya derzhavno-pryvatnogo partnerstva, yih ocinky ta vyznachennya formy upravlinnya nymy : Postanova [On approval of Methodology identify risks of public-private partnership, their evaluation and determination of management forms: Resolution], Oficijnyj visnyk Ukrayiny, vol. 18, art. 769.14. The Cabinet of Ministers of Ukraine (2015), Pro vnesennya zmin do postanovy Kabinetu Ministriv Ukrayiny vid 16 lyutogo 2011 r. № 232 : Postanova [On Amendments to Resolution of The Cabinet of Ministers of Ukraine on February 16, 2011, Number 232:],Oficijnyj visnyk Ukrayiny, vol. 76, art. 2525.

Open access
Economic Issues in Ukraine
Business and Economic Development
Labor Market and Education
Original source
Jul 18, 2017¡arXiv (Cornell University)
42 cites
Teechain: Scalable Blockchain Payments using Trusted Execution Environments.

Joshua Lind, Ittay Eyal, Florian Kelbert, Oded Naor ¡ 6 authors

Blockchains such as Bitcoin and Ethereum execute payment transactions securely, but their performance is limited by the need for global consensus. Payment networks overcome this limitation through off-chain transactions. Instead of writing to the blockchain for each transaction, they only settle the final payment balances with the underlying blockchain. When executing off-chain transactions in current payment networks, parties must access the blockchain within bounded time to detect misbehaving parties that deviate from the protocol. This opens a window for attacks in which a malicious party can steal funds by deliberately delaying other parties' blockchain access and prevents parties from using payment networks when disconnected from the blockchain. We present Teechain, the first layer-two payment network that executes off-chain transactions asynchronously with respect to the underlying blockchain. To prevent parties from misbehaving, Teechain uses treasuries, protected by hardware trusted execution environments (TEEs), to establish off-chain payment channels between parties. Treasuries maintain collateral funds and can exchange transactions efficiently and securely, without interacting with the underlying blockchain. To mitigate against treasury failures and to avoid having to trust all TEEs, Teechain replicates the state of treasuries using committee chains, a new variant of chain replication with threshold secret sharing. Teechain achieves at least a 33x higher transaction throughput than the state-of-the-art Lightning payment network. A 30-machine Teechain deployment can handle over 1 million Bitcoin transactions per second.

Open access
Distributed systems and fault tolerance
Blockchain Technology Applications and Security
Security and Verification in Computing
Original source
Jul 18, 2017¡arXiv (Cornell University)
24 cites
Teechain: A Secure Payment Network with Asynchronous Blockchain Access

Joshua Lind, Oded Naor, Ittay Eyal, Florian Kelbert ¡ 6 authors

Blockchains such as Bitcoin and Ethereum execute payment transactions securely, but their performance is limited by the need for global consensus. Payment networks overcome this limitation through off-chain transactions. Instead of writing to the blockchain for each transaction, they only settle the final payment balances with the underlying blockchain. When executing off-chain transactions in current payment networks, parties must access the blockchain within bounded time to detect misbehaving parties that deviate from the protocol. This opens a window for attacks in which a malicious party can steal funds by deliberately delaying other parties' blockchain access and prevents parties from using payment networks when disconnected from the blockchain. We present Teechain, the first layer-two payment network that executes off-chain transactions asynchronously with respect to the underlying blockchain. To prevent parties from misbehaving, Teechain uses treasuries, protected by hardware trusted execution environments (TEEs), to establish off-chain payment channels between parties. Treasuries maintain collateral funds and can exchange transactions efficiently and securely, without interacting with the underlying blockchain. To mitigate against treasury failures and to avoid having to trust all TEEs, Teechain replicates the state of treasuries using committee chains, a new variant of chain replication with threshold secret sharing. Teechain achieves at least a 33x higher transaction throughput than the state-of-the-art Lightning payment network. A 30-machine Teechain deployment can handle over 1 million Bitcoin transactions per second.

Open access
2 source records
cs.CR
Blockchain Technology Applications and Security
Distributed systems and fault tolerance
Original source
Jul 18, 2017¡Environments
328 cites
Blockchain: The Evolutionary Next Step for ICT E-Agriculture

Yu‐Pin Lin, Joy R. Petway, Johnathen Anthony, Hussnain Mukhtar · 7 authors

Blockchain technology, while still challenged with key limitations, is a transformative Information and Communications Technology (ICT) that has changed our notion of trust. Improved efficiencies for agricultural sustainable development has been demonstrated when ICT-enabled farms have access to knowledge banks and other digital resources. UN FAO-recommended ICT e-agricultural infrastructure components are a confluence of ICT and blockchain technology requirements. When ICT e-agricultural systems with blockchain infrastructure are immutable and distributed ledger systems for record management, baseline agricultural environmental data integrity is safeguarded for those who participate in transparent data management. This paper reviewed blockchain-based concepts associated with ICT-based technology. Moreover, a model ICT e-agriculture system with a blockchain infrastructure is proposed for use at the local and regional scale. To determine context specific technical and social requirements of blockchain technology for ICT e-agriculture systems, an evaluation tool is presented. The proposed system and tool can be evaluated and applied to further developments of e-agriculture systems.

Open access
2 source records
Blockchain Technology Applications and Security
IoT and Edge/Fog Computing
Food Waste Reduction and Sustainability
Original source
Jul 14, 2017¡arXiv
0 cites
Image-based Proof of Work Algorithm for the Incentivization of Blockchain Archival of Interesting Images

Jake Billings

A new variation of blockchain proof of work algorithm is proposed to incentivize the timely execution of image processing algorithms. A sample image processing algorithm is proposed to determine interesting images using analysis of the entropy of pixel subsets within images. The efficacy of the image processing algorithm is examined using two small sets of training and test data. The interesting image algorithm is then integrated into a simplified blockchain mining proof of work algorithm based on Bitcoin. The incentive of cryptocurrency mining is theorized to incentivize the execution of the algorithm and thus the retrieval of images that satisfy a minimum requirement set forth by the interesting image algorithm. The digital storage implications of running an image- based blockchain are then examined mathematically.

Open access
cs.CR
Original source
Jul 14, 2017¡Publications
40 cites
A Proposed Currency System for Academic Peer Review Payments Using the BlockChain Technology

Michael Spearpoint

Peer review of scholarly papers is seen to be a critical step in the publication of high quality outputs in reputable journals. However, it appears that there are few incentives for researchers to agree to conduct suitable reviews in a timely fashion and in some cases unscrupulous practices are occurring as part of the production of academic research output. Innovations in internet-based technologies mean that there are ways in which some of the challenges can be addressed. In particular, this paper proposes a new currency system using the BlockChain as its basis that provides a number of solutions. Potential benefits and problems of using the technology are discussed in the paper and these will need further investigation should the idea develop further. Ultimately, the currency could be used as an alternative publication metric for authors, institutions and journals.

Open access
Flow Experience in Various Fields
Original source
Jul 13, 2017¡arXiv (Cornell University)
2 cites
RDV: An Alternative To Proof-of-Work And A Real Decentralized Consensus For Blockchain

Siamak Solat

A blockchain is a decentralized ledger where all transactions are recorded. For having a reliable blockchain and double-spending prevention, we need a decentralized consensus and agreement on a blockchain. Bitcoin uses proof-of-work (PoW). It is a cryptographic puzzle that is difficult to solve but easy to verify. However, because of significant latency of proof-of-work for transactions confirmation, this consensus mechanism is vulnerable against double-spending. On the other hand, PoW consumes a significant amount of energy that by growing the network, it becomes a major problematic of this consensus mechanism. In this paper, we introduce an alternative to PoW, because of all its major problems and security issues that may lead to collapsing decentralization of the blockchain, while a full decentralized system is the main purpose of using blockchain technology. The approach we introduce is based on a distributed voting process and called "RDV: Register, Deposit, Vote". Since in RDV algorithm, there is no mining process, so it is appropriate for low-level energy devices and Internet of Things (IoT).

Open access
3 source records
cs.CR
Blockchain Technology Applications and Security
Cryptography and Data Security
Original source
Jul 12, 2017¡arXiv (Cornell University)
0 cites
Modeling the price of Bitcoin with fractional Brownian motion: a Monte Carlo approach

Mariusz Tarnopolski

The long-term dependence of Bitcoin (BTC), manifesting itself through a Hurst exponent $H>0.5$, is exploited in order to predict future BTC/USD price. A Monte Carlo simulation with $10^4$ geometric fractional Brownian motion realisations is performed as extensions of historical data. The accuracy of statistical inferences is 10\%. The most probable Bitcoin price at the beginning of 2018 is 6358 USD.

Open access
Complex Systems and Time Series Analysis
Original source
Jul 12, 2017¡Spiral (Imperial College London)
97 cites
Glamdring: automatic application partitioning for intel SGX

Joshua Lind, Christian Priebe, Divya Muthukumaran, Dan O’Keeffe · 12 authors

Trusted execution support in modern CPUs, as offered by Intel SGX enclaves , can protect applications in untrusted environments. While prior work has shown that legacy applications can run in their entirety inside enclaves, this results in a large trusted computing base (TCB). Instead, we explore an approach in which we partition an applica- tion and use an enclave to protect only security-sensitive data and functions, thus obtaining a smaller TCB. We describe Glamdring , the first source-level parti- tioning framework that secures applications written in C using Intel SGX. A developer first annotates security- sensitive application data. Glamdring then automatically partitions the application into untrusted and enclave parts: (i) to preserve data confidentiality, Glamdring uses dataflow analysis to identify functions that may be ex- posed to sensitive data; (ii) for data integrity, it uses back- ward slicing to identify functions that may affect sensitive data. Glamdring then places security-sensitive functions inside the enclave, and adds runtime checks and crypto- graphic operations at the enclave boundary to protect it from attack. Our evaluation of Glamdring with the Mem- cached store, the LibreSSL library, and the Digital Bitbox bitcoin wallet shows that it achieves small TCB sizes and has acceptable performance overheads.

Open access
Security and Verification in Computing
Cloud Data Security Solutions
Distributed systems and fault tolerance
Original source
Jul 12, 2017¡arXiv (Cornell University)
6 cites
Modeling the price of Bitcoin with geometric fractional Brownian motion: a Monte Carlo approach

Mariusz Tarnopolski

The long-term dependence of Bitcoin (BTC), manifesting itself through a Hurst\nexponent $H>0.5$, is exploited in order to predict future BTC/USD price. A\nMonte Carlo simulation with $10^4$ geometric fractional Brownian motion\nrealisations is performed as extensions of historical data. The accuracy of\nstatistical inferences is 10\\%. The most probable Bitcoin price at the\nbeginning of 2018 is 6358 USD.\n

Open access
3 source records
q-fin.CP
econ.GN
q-fin.ST
Original source
Jul 11, 2017¡Journal of Cancer Policy
19 cites
A comprehensive assessment of breast and cervical cancer control infrastructure in Zambia

Carla J. Chibwesha, Leeya F. Pinder, Agnes Musonda, Kombatende Sikombe ¡ 11 authors

Introduction: By 2030 cancer will kill one million Africans each year. Women will bear the heaviest burden, as cancers of the breast and cervix are the most common malignancies and causes of cancer-related death in the African region. National-level data that map the status of women's cancer control services are needed to inform strategies for implementing platforms for the early detection and treatment of these “priority” cancers. Methods: Using mixed-methods, we assessed available services for breast and cervical cancer detection and treatment at all provincial hospitals, the national referral hospital, and the national cancer treatment center in Zambia. Results: A system for cervical cancer prevention using visual inspection with acetic acid (VIA) and ablation/excision of precancerous lesions has been established at the provincial level. The potential for mammography, clinical breast examination, diagnostic ultrasound and biopsy exist at the provincial level, albeit on a much smaller scale. Breast wedge resections and mastectomy can be performed in provinces where general surgeons are located; however, breast conserving and reconstructive surgery are not available. Invasive cancers are generally referred to University Teaching Hospital in Lusaka, where services for radiation, chemotherapy and hormonal therapy are available but overburdened. Pathology services nationwide are woefully inadequate. Discussion: The assessment revealed a critical need for centrally coordinated, but decentralized, public service platforms for women's cancer control. Efforts are underway, through multiple stakeholders, to implement recommendations related to training healthcare workers who can provide advanced diagnostic and therapeutic services, improving pathology services, and innovative financing for these initiatives.

Open access
2 source records
Cervical Cancer and HPV Research
Global Cancer Incidence and Screening
Colorectal Cancer Screening and Detection
Original source
Jul 11, 2017¡Open Repository of the University of Porto (University of Porto)
1 cites
Peer to Peer Insurance over Blockchain

Ricardo Jorge Matos Figueiredo

General Insurance occupies a strong position in today's market. It has a centralized way of operation, which makes it inefficient, less transparent, with trust problems and creates conflicts of interest between insurance companies and policyholders. Furthermore, it's an industry with relative difficulty in innovation, which contrasts with today's services powered by new technologies. New disruptive technologies have the capacity to compromise the value chain of traditional insurance, creating a big problem in its stability and future. Associated to this new kind of technologies, comes a new way of thinking perpetuated by the new generations based on the new trend of sharing economy. They give priority to new technology based services, which are decentralized, more convenient, more price competitive, transparent, and efficient and they prefer services which put the user more in control instead of the current less personalized options. New business models such as Social Insurance, are being developed and powered by new technologies and this new way of thinking. Social Insurance enables people in need of insurance to connect and pool their money and risks. It offers coverage that is cheaper, more transparent, and more relevant to the customer. Members of this type of insurance are both policyholders and underwriters. All these factors compromise the future of traditional insurance companies and their business model. The main goal is to create a new business model in order to adapt insurance companies to the new trend of shared economy. This new business model is going to be focused on health insurance, based in peer to peer communication and is going to be backed up by a business case and a prototype powered by a blockchain database. Blockchain is a decentralized transaction ledger shared amongst all nodes participating in the system. Every node has an updated copy of the database and cannot update it without the consensus of the network, removing the need for having a central authority or trusted third party to monitor the system. Each Blockchain implementation may have its own consensus mechanism (e.g. Proof-of-Work and Proof-of-Stake) to ensure that one node on its own cannot change the database without being validated by the network. Bitcoin is the world's most well-known Blockchain implementation, a public ledger for all transactions made in with a digital currency. However, Blockchain technology can be applied to multiple use cases and industries using Smart Contracts (a collection of code that runs on the network) to define the rules of the business. It fits the purpose for this business model, because it has peer to peer communication by default and has no central authority, making the service more efficient and transparent.

Open access
Blockchain Technology Applications and Security
FinTech, Crowdfunding, Digital Finance
Original source
Jul 10, 2017¡DergiPark (Istanbul University)
0 cites
REFORM AND DECENTRALIZATION IN FRANCE: AN EVALUATION THROUGH THE LENS OF TURKISH SYSTEM

Yeşeren ELİÇİN

France undergoes a decentralization process since the early 1980s. French local administrations experienced significant transformations during this process, embracing three action periods. The decentralization acts enacted in 1982 mark disengagement with administrative uniformity. The second period of decentralization starting the first years of 2000s witnessed important constitutional modifications. Regional administrations gained Constitutional recognition, local referendum has been established, the amendments concerning right to petition, experimentation, local finance and local autonomy has been passed. The third phase of decentralization started since 2010s. The reorganization of metropolitan governance, the transfer of competence to inter-communal cooperation structures concerning urban planification, roles assigned to regions in economic development and employment (economical issues, apprenticeship, European aides and aides destined to private sector), territorial solidarity and reinforcement of democracy were the main themes of this phase. The present article tries to analyze the foremost futures of French decentralization and to underline the main discussions emerged during the ongoing third phase of decentralization process concerning future of departments, regional administration and newly created metropolitan cities. In the last part of the article, the probable influences of French reforms on Turkey are discussed taking into account that Turkey has taken this country as a model in its administrative organization.

Open access
European Union Policy and Governance
Original source
Jul 10, 2017¡International Journal of Scientific Research and Management (IJSRM)
1 cites
Necessity and Implementation of BlockChain Technology

Waseem Akram Mir

Transactions between individuals have always been a part and parcel of human society for the division of labour made people interdependent. The medium of transaction has also been evolving along with the evolution of society and human consciousness from barter system to commodity money to fiat currency and now to digital currency or cryptocurrency. But since evolution is a form of error correction, the problem of double spending in digital currency was solved by a distributed ledger system called Blockchain. Since 2008 onwards the blockchain technology has been separated from bitcoins to be injected to many other problems related especially to banking transactions. Blockchain technology enables the creation of decentralized currencies, smart contracts and intelligent assets that can be controlled over the Internet

Open access
Blockchain Technology Applications and Security
FinTech, Crowdfunding, Digital Finance
IoT and Edge/Fog Computing
Original source
Jul 10, 2017¡edoc Publication server (Humboldt University of Berlin)
1 cites
Investing with cryptocurrencies

Simon Trimborn, Mingyang Li, Wolfgang Karl Härdle

Cryptocurrencies have left the dark side of the finance universe and become an object of study for asset and portfolio management. Since they have a low liquidity compared to traditional assets, one needs to take into account liquidity issues when one puts them into the same portfolio. We propose use a LIquidity Bounded Risk-return Optimization (LIBRO) approach, which is a combination of the Markowitz framework under the liquidity constraints. The results show that cryptocurrencies add value to a portfolio and the optimization approach is even able to increase the return of a portfolio and lower the volatility risk. The codes used to obtain the results in this paper are available via www.quantlet.de

Open access
FinTech, Crowdfunding, Digital Finance
Original source
Jul 10, 2017¡Frontiers in Energy Research
45 cites
Promoting Decentralized Sustainable Energy Systems in Different Supply Scenarios: The Role of Autarky Aspiration

Franz Ecker, Ulf J.J. Hahnel, Hans Spada

The development of decentralized renewable energy systems is of crucial importance for the decarbonization of energy generation worldwide. Purchase decisions regarding innovative energy systems depend to some extent on consumers' perception of the systems' degree of autarky. We assumed that, in addition to the energetic perspective, consumers associate other non-energetic facets such as independence, autonomy, self-sufficiency or control with the concept of autarky. These psychological facets of autarky were expected to contribute to purchase decisions. In Study 1, participants (\textit{N}=168) evaluated three future energy supply scenarios. The scenarios varied regarding their range of autarky (household/ neighborhood/ small town), but the individually realized degree of energetic autarky did not vary. Participants reported a higher willingness to pay in connection with a higher perceived psychological autarky for the Household Scenario. Study 1's findings were confirmed by Study 2, in which qualitative interviews (\textit{N}=13) also revealed that participants favored the Household Scenario on several points. These evaluations were driven by the anticipated psychological facets of autarky, that is the subjective perception of being independent, autonomous, self-sufficient, energy secure and of control. To promote an adoption of renewable energy systems, these psychological autarky facets need to be addressed. Enabling the people to self-determine, control and secure their energy provision even in complex organizational settings in such a manner is likely to increase their acceptance and therefore foster the required social transition as a whole.

Open access
Environmental Education and Sustainability
Climate Change Communication and Perception
Social Acceptance of Renewable Energy
Original source
Jul 7, 2017¡RePEc: Research Papers in Economics
4 cites
Securities Regulation in Canada at a Crossroads

Pierre Lortie

On May 26, 2010, Canada’s Minister of Finance tabled in the House of Commons a draft Securities Act. The purpose of the Act is to establish Federal government jurisdiction over securities legislation and create a Federal Securities Regulatory Authority. With this initiative, the Federal government proposes to centralize the regulatory apparatus to ensure uniformity of policies and regulations across Canada and meet international standards of quality and comprehensiveness. But this initiative also raises significant constitutional and economic policy issues. In a comprehensive paper examining the main arguments supporting a centralized securities apparatus, Pierre Lortie, Senior Business Advisor at Fraser Milner Casgrain LLP, argues that sound public policy should move ahead only if there is a strong body of empirical evidence demonstrating that the performance of the current regime is significantly inferior to that of other countries — particularly the United States — and that a centralization of the regulatory apparatus is necessary to correct the situation. The paper demonstrates that Canada’s decentralized securities regulatory regime has in fact shown flexibility, a great capacity to adapt to changing circumstances and an unrelenting ability to respond to particular industry or regional needs. It has also provided strong assurances against the hasty adoption of disruptive and costly regulations because it is less susceptible to the imposition of politically expedient or faddish requirements or the influence of a dominant industry or interest groups. In contrast, a centralized system runs the risk of turning into a disruptive, costly and regrettable initiative that will not give Canadians what they expect, while erasing many of the benefits achieved so far.

Open access
Canadian Policy and Governance
Global Financial Regulation and Crises
Law, logistics, and international trade
Original source
Jul 6, 2017¡Lecture notes in computer science
12 cites
A Logic of Blockchain Updates

Kai BrĂźnnler, Dandolo Flumini, Thomas Studer

Abstract Blockchains are distributed data structures that are used to achieve consensus in systems for cryptocurrencies (like Bitcoin) or smart contracts (like Ethereum). Although blockchains gained a lot of popularity recently, there are only few logic-based models for blockchains available. We introduce $\mathsf{BCL}$, a dynamic logic to reason about blockchain updates, and show that $\mathsf{BCL}$ is sound and complete with respect to a simple blockchain model.

Open access
3 source records
cs.LO
Logic, Reasoning, and Knowledge
Distributed systems and fault tolerance
Original source
Jul 6, 2017¡arXiv (Cornell University)
257 cites
Blockchain Consensus Protocols in the Wild

Christian Cachin, Marko Vukolić

A blockchain is a distributed ledger for recording transactions, maintained by many nodes without central authority through a distributed cryptographic protocol. All nodes validate the information to be appended to the blockchain, and a consensus protocol ensures that the nodes agree on a unique order in which entries are appended. Consensus protocols for tolerating Byzantine faults have received renewed attention because they also address blockchain systems. This work discusses the process of assessing and gaining confidence in the resilience of a consensus protocols exposed to faults and adversarial nodes. We advocate to follow the established practice in cryptography and computer security, relying on public reviews, detailed models, and formal proofs; the designers of several practical systems appear to be unaware of this. Moreover, we review the consensus protocols in some prominent permissioned blockchain platforms with respect to their fault models and resilience against attacks. The protocol comparison covers Hyperledger Fabric, Tendermint, Symbiont, R3~Corda, Iroha, Kadena, Chain, Quorum, MultiChain, Sawtooth Lake, Ripple, Stellar, and IOTA.

Open access
2 source records
Blockchain Technology Applications and Security
Distributed systems and fault tolerance
Cryptography and Data Security
Original source
Jul 5, 2017¡Preprints.org
1 cites
Delphi Expert Survey on Climate Policies, Plans/Strategies in Nepal

Shree Kumar Maharjan, Keshav Lall Maharjan

The government of Nepal (GoN) has developed and implemented climate policies, plans and frameworks such as NAPA, National Climate Change Policy, LAPA and currently in the process of developing National Adaptation Plans (NAPs). These policies and plans are in different states of its implementation with diverse opinions and perceptions of the stakeholders. The paper has explored these opinions and experiences of climate experts in Nepal on state of climate policies, inter-linkages, roles and responsibilities of ministries/departments, important factors and subjective indicators for effective implementation of the policies. Altogether 30 experts responded the questionnaire sent via the email, LinkedIn and Skype Interview in the 1st phase of Delphi research technique. The experiences of these experts range from 2-30 years representing government, non-government sectors, media and independent experts. As per most of the experts interviewed, the policies and plans are progressing in strategic direction with national and local priorities. The LAPA is the pioneer framework to address the local climatic issues, originated in Nepal. However, lack of clarity on roles/responsibilities and coordination among the ministries/departments; clear mechanisms for implementation of these policies; lack of sensitization, decentralization and delegation of finance and technologies; capacity of the stakeholders are the major challenges identified.

Open access
Sustainability and Climate Change Governance
Original source
Jul 4, 2017¡International Journal for Court Administration
9 cites
Integrated Justice: An Information Systems Approach to Justice Sector Case Management and Information Sharing

Adam Watson, Regis Rukundakuvaga, Khachatur Matevosyan

Automated Case Management Systems are still at an early stage of adoption in many developing countries. These are frequently standalone systems implemented with donor financing, and they often fail due to capacity constraints or as a consequence of short-term, project-based funding. But there are examples of developing countries overcoming these pitfalls and producing innovative solutions that surpass government practices in more developed countries. The Integrated Electronic Case Management System (IECMS), developed and implemented by the Ministry of Justice of Rwanda from 2015-2016, is one such innovation. This system has progressed rapidly in its level of adoption and integration between law enforcement, the prosecutor’s office, courts, and corrections. This paper will discuss the key system functionalities and the implementation methodology, including both the benefits and shortcomings of this approach, with the goal of applying lessons learned in future installations. Foremost among the successes of this project were the integrated Sector Wide Approach, the thorough business process re-engineering, and strong ownership by the Rwandan Justice Sector staff. Particularly instructive will be the analysis of the integrated approach, covering five institutions with a single system in less than two years. However, the particular success in this case may not be replicable for governments with a more decentralized approach.

Open access
Business Process Modeling and Analysis
Artificial Intelligence in Law
Big Data and Business Intelligence
Original source
Jul 3, 2017¡Law Innovation and Technology
43 cites
Bitcoins and other cryptocurrencies as property?

Kelvin Fatt Kin Low, Ernie G. S. Teo

The hype over bitcoins has been compared to the tulip mania in 17th century Netherlands and it has spawned a host of similar cryptocurrencies. As it has gained in popularity, the law has approached the subject warily, mostly from a regulatory perspective. However, no comprehensive consideration of the fundamental nature of a bitcoin owner’s private law relation to his/her/its bitcoins has been properly conducted. Whether or not bitcoins or other cryptocurrencies achieve mainstream adoption or remain of interest to only a niche audience, this question will inevitably have to be properly addressed. This paper proposes to consider if bitcoins might be recognised as the subject of property rights by Commonwealth courts and if so, what such rights ought to entail. It will begin with a careful consideration of the controversial question of the scope of the law of property before considering bitcoin’s place within the law of property (if any). What is the meaning of property in the common law? What fundamental differences exist between tangible and intangible property? If ownership of bitcoins is worthy of protection, what shape should it take? It suggests that the common law adopts a more expansive view of property than civilian systems and that it is thus able to accommodate bitcoins and other cryptocurrencies within its law of property. However, owing to their unusual nature, legal rights to them must take on a unique and unorthodox form. The code underlying Bitcoin also poses particular challenges to the law which this paper also addresses.

Open access
2 source records
Blockchain Technology Applications and Security
European and International Contract Law
Legal principles and applications
Original source
Jul 1, 2017¡Proceedings on Privacy Enhancing Technologies
22 cites
PathShuffle: Credit Mixing and Anonymous Payments for Ripple

Pedro Moreno-SĂĄnchez, Tim Ruffing, Aniket Kate

Abstract The I owe you (IOU) credit network Ripple is one of the most prominent alternatives in the burgeoning field of decentralized payment systems. Ripple’s path-based transactions set it apart from cryptocurrencies such as Bitcoin. Its pseudonymous nature, while still maintaining some regulatory capabilities, has motivated several financial institutions across the world to use Ripple for processing their daily transactions. Nevertheless, with its public ledger, a credit network such as Ripple is no different from a cryptocurrency in terms of weak privacy; recent demonstrative deanonymization attacks raise important concerns regarding the privacy of the Ripple users and their transactions. However, unlike for cryptocurrencies, there is no known privacy solution compatible with the existing credit networks such as Ripple. In this paper, we present PathShuffle, the first path mixing protocol for credit networks. PathShuffle is fully compatible with the current credit networks. As its essential building block, we propose PathJoin, a novel protocol to perform atomic transactions in credit networks. Using PathJoin and the P2P mixing protocol DiceMix, PathShuffle is a decentralized solution for anonymizing path-based transactions. We demonstrate the practicality of PathShuffle by performing path mixing in Ripple.

Open access
Blockchain Technology Applications and Security
Privacy-Preserving Technologies in Data
Cryptography and Data Security
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