Follow blockchain research across journals, conferences, and preprint repositories.
13,620 results · page 473 of 568
M S Urmila, Balaji Hariharan, Rekha Prabha
No abstract is available for this record.
Fatima Tariq, Zahoor Ali Khan, Tanzeela Sultana, Mubariz Rehman · 6 authors
No abstract is available for this record.
Cristina Pérez Solà
No abstract is available for this record.
Henri T. Heinonen, Alexander Semenov, Vladimir Boginski
No abstract is available for this record.
Abhay Goel, Abhishek Sharma, Deepak Gupta, Ashish Khanna
No abstract is available for this record.
Saurabh Kumar
The prices of cryptocurrencies are very volatile and forecasting them is a challenging task for the researchers across the world. The present study examines the accuracy of forecasted returns of the two most popular cryptocurrencies (Bitcoin and Ethereum) for the sample period spanning from October 1, 2013, to November 30, 2018. Auto-regressive integrated moving average (ARIMA) and Neural Network models have been used to forecast the returns of the cryptocurrencies. The forecasting results for different time-horizons indicate that for a shorter time-horizon, ARIMA model is better for forecasting the returns of cryptocurrencies, whereas, for a longer time-horizon, Neural Network model is better for forecasting the returns of cryptocurrencies. These results have implications for traders, investors, regulators, policymakers and academia.
Zhijie Zhang, Lejun Zhang, Waqas Rasheed, Zilong Jin · 7 authors
No abstract is available for this record.
di Angelo Monika, Salzer Gernot
No abstract is available for this record.
Jason Orender, Ravi Mukkamala, Mohammad Zubair
Cryptocurrencies are more than a decade old and several issues have been discovered since their then. One of these issues is a partial negation of the intent to “democratize” money by decentralizing control of the infrastructure that creates, transmits, and stores monetary data. The Programmatic Proof of Work (ProgPoW) algorithm is intended as a possible solution to this problem for the Ethereum cryptocurrency. This paper examines ProgPow’s claim to be Application Specific Integrated Circuit (ASIC) resistant. This is achieved by isolating the proof-of-work code from the Ethereum blockchain, inserting the ProgPoW algorithm, and measuring the performance of the new implementation as a multithread CPU program, as well as a GPU implementation. The most remarkable difference between the ProgPoW algorithm and the currently implemented Ethereum Proof-of Work is the addition of a random sequence of math operations in the main loop that require increased memory bandwidth. Analyzing and comparing the performance of the CPU and GPU implementations should provide an insight into how the ProgPoW algorithm might perform on an ASIC.
Amal Abid, Saoussen Cheikhrouhou, Mohamed Jmaïel
No abstract is available for this record.
Xiangbin Xian, Zhenguo Yang, Guipeng Zhang, Tucua Miro de Nelio S. · 5 authors
No abstract is available for this record.
Khaled Lafi AL-Naif
The purpose of this study is to investigate the relationship between the exchange rate returns of the top three cryptocurrencies (Bitcoin, Ethereum and Ripple) and eight of Arabian currencies, namely; Egyptian Pound, Iraqi dinar, Lebanese Lira, Moroccan Dirham, Omani Riyal, Qatari riyal Saudi Arabian Riyal, and Tunisian Dinar, against US dollar. Daily exchange rate closing price (against US$) data for the chosen sample in the period between 1st of Jan 2017 and 1st of Jan 2020 were obtained from different sources. To analyze these data, several statistical methods have been used, such as multiple regression analyses, unit root test, and correlations. The results indicated that, (with the exception of Lebanese Lira with Bitcoin and with Ripple, Moroccan Dirham with Ethereum, Iraqi dinar with Ripple), there were no significant relationships between the Arabian currencies and cryptocurrencies exchange rate. On the other hand, the results showed a significant positive relationship between Bitcoin, Ethereum and Ripple. Finally, the study concluded that, since there was a negative relationship between Iraqi dinar and Ripple, the former can benefit in hedging and diversification. The study also concluded that Arabian countries exchange markets do not highly affect the cryptocurrencies markets, which may be due to the absence of legal recognition by governments besides the absence of the public acceptance for such currency.
Arjun Singh
This paper examines the market efficiency of three key cryptocurrency markets namely: Bitcoin, Ethereum and Monero, before and during the COVID-19 pandemic. This research makes use of a Durbin-Watson test and a non-parametric runs test to test for weak-form efficiency, and two comprehensive event studies to test for semi-strong form and strong form efficiency. We conclude neither market can be considered efficient due to the presence of strong positive correlation, and inefficient reactions to our event studies. Despite this, each market became more efficient during the COVID-19 pandemic than before, due to the presence of weaker positive correlation during this timeframe, but inefficient, nonetheless. Thus, the study finds that of the tested cryptocurrency markets, none can be consider wholly efficient. This conclusion is consistent with the vast majority of existing literature.
Ashish Sharma, Yogesh Sharma, Radhika Bansal, Sushant Kumar Verma
The paper aims at creating ERC-20 Token and crowd sale step-by-step with Ethereum smart contracts. In the process, it focuses on testing the smart contracts, deploying the smart contracts to the Ethereum blockchain, and building an ICO website deployed to the web for the buying and selling of the tokens. The Ethereum blockchain provides a platform for creating our cryptocurrency, or tokens that can be purchased via Ether which is the native cryptocurrency of the Ethereum blockchain. ERC-20 is a standard document that specifies the behavior of the tokens so that they are compatible with other platforms like cryptocurrency exchanges. We used Ethereum which is a blockchain like Bitcoin. We created a token called ;Token ; and there are 100,000,000 such tokens. Firstly, the token smart contract keeps track of some token attributes which are basic. It also keeps track of who owns ;My Token ; and how much. ERC-20 tokens can be used as a payment just, just like any other cryptocurrency, from one account to another. They can also be purchased in a crowd sale, like an ICO.
Armando Ruggeri, Maria Fazio, Antonio Celesti, Massimo Villari
No abstract is available for this record.
Naoya Okanami, Ryuya Nakamura, Takashi Nishide
Sharding is an approach to designing a highly scalable blockchain. A sharded blockchain achieves parallelism by dividing consensus nodes (validators) into groups called shards and making them process different transactions in each shard. In this paper, we economically analyze users’ behavior on sharded blockchains and identify a phenomenon that users’ accounts and smart contracts eventually get concentrated in a few shards, making shard loads unfair. This phenomenon leads to bad user experiences, such as delays in transaction inclusions and increased transaction fees. To solve the above problem, we propose a load balancing ramework in sharded blockchains in which accounts and contracts are frequently reassigned into shards to reduce the difference of loads between shards. We formulate the contract reassignment as an optimization problem and present the algorithm to solve it. Further, we apply the framework to an existing sharding design (Ethereum 2.0) and modify the protocol to do load balancing. Finally, we simulate the protocol and observe smaller transaction delays and fees.
Naipeng Dong, Guangdong Bai, Lung-Chen Huang, Edmund Kok Heng Lim · 5 authors
Abstract Blockchain technology has rapidly emerged as a decentralized trusted network to replace the traditional centralized intermediator. Especially, the smart contracts that are based on blockchain allow users to define the agreed behaviour among them, the execution of which will be enforced by the smart contracts. Based on this, we propose a decentralized booking system that uses the blockchain as the intermediator between hoteliers and travellers. The system enjoys the trustworthiness of blockchain, improves efficiency and reduces the cost of the traditional booking agencies. The design of the system has been formally modelled using the CSP# language and verified using the model checker Process Analysis Toolkit. We have implemented a prototype decentralized booking system based on the Ethereum ecosystem.
Mahmoud El-Gayyar, Hany F. ElYamany, Katarina Grolinger, Miriam A. M. Capretz · 5 authors
A federated identity is a single identity that enables users to access multiple services across a network of business parties. Such identities are subject to various threats and attacks and face diverse challenges including identity leaks, centralised management, auditing limitations, and long breach investigation processes. This paper proposes a framework aimed at automating and decentralising the generation and auditing of a robust and secured blockchain-based federated identity in a marketplace. Business parties participating in the marketplace form the nodes of a distributed blockchain network and participate in the creation of federated identities. Users of this network can access services provided by any one of the participating parties using a single federated identity. All transactions are fully audited in the blockchain, meaning that participating parties can monitor access to their service and users can trace the use of their identities. The proposed framework has been evaluated using two blockchain technologies (Ethereum and Hyperledger Fabric) to measure its performance in public and permissioned blockchain environments.
Lukáš Pichl, Zheng Nan, Taisei Kaizoji
No abstract is available for this record.
James P. Howard, Maria E. Vachino
Under current Federal Information Security Management Act of 2002 (FISMA) requirements, all new federal IT programs and modernization efforts using blockchain must meet National Institute of Standards and Technology (NIST) cryptographic standards. This article evaluates four major blockchain technologies-Ethereum, Hyperledger Fabric, R3's Corda, and Multichain-to determine their level of NIST compliance.
Beltrán Borja Fiz Pontiveros, Christof Ferreira Torres, Radu State
No abstract is available for this record.
Niclas Kullig, Philipp Lämmel, Nikolay Tcholtchev
With the greater availability and reduced dimensions of complex electronics, an Internet of Things (IoT) will emerge in the future, in which machines use sensors to collect and evaluate information about the physical world and share it with other machines without having to rely on human interaction. Blockchain technology encompasses features such as trustworthiness and decentralization and these features can be advantageous in the IoT context, as they can help to ensure data integrity in an Internet of Things unmonitored by humans. In the course of this paper, we investigate to what extent the use of blockchain technology is feasible for autonomous devices in IoT. For this purpose, a prototypical client blockchain component is built using the single-board computer Raspberry Pi and a simulated Ethereum blockchain. This prototype will be examined for aspects like proper functionality, response times and performance.
Bikram Shrestha, Malka N. Halgamuge, Horst Treiblmaier
No abstract is available for this record.
Mehtab Alam, Ihtiram Raza Khan, Safdar Tanweer
No abstract is available for this record.