In proof-of-work (PoW)-based blockchain network, the blockchain miners publish blocks by contributing computing power to solve crypto-puzzles.Due to the weak computing power of single miner, miners tend to join a mining pool and share the profits from the mining pool according to the contribution proportions of the miners.However, some miners may initiate block withholding attack which may result in wasting computing power, even threatening the efficiency of the blockchain network.To address this problem, in this paper, we use the biform game model to optimize the miners' strategy choices.We firstly formulate the mining process as a non-cooperative-cooperative biform game model.We use the model to exhibit miners' strategy choices (non-cooperation stage) and the cooperation mining process (cooperation stage).Then we set the conditions to maintain the voluntary honest behavior of miners.After that, we employ the semi-CIS (semi-the center of imputation set value) value to compute the solutions of the cooperative games in the cooperation stage, and optimize miners' strategy choices to prevent the block withholding attack.Hence we can ensure the blockchain network is secure.Finally, the validity and applicability of the proposed model and method are verified by a numerical example.
Benedikt Betzwieser, Sebastian Franzbonenkamp, Tobias Riasanow, Markus Bรถhm ยท 6 authors
Blockchain technology is said to have a tremendous impact on business and society. As blockchain is currently on top of the famous Gartnerโs hype cycle, many organizations are beginning to experiment with the technology. However, the majority of these projects fail or are abandoned. Existing decision models that could help to counteract this problem lack important aspects. Therefore, we provide a comprehensive decision model for the implementation of blockchain solutions. Our decision model highlights prerequisites, business and technical considerations, and discusses design decisions of blockchain solutions. Besides the advantages, we show that blockchain technology has limitations that may restrict its application such as a lack of standards. Scholars can apply the decision model for future research, while practitioners can use it to assess and design a potential blockchain implementation.
The evolution of financial technology adds to the complexity of the global financial system and the underlying assets that store its value.This complexity manifests as an adverse market risk profile in assets where fintech can be considered an endogenous variable.A theoretical framework that may contribute toward an improved understanding of this relationship is established.In contrast to the adverse risk profile in these markets, however, the literature still suggests a value proposition in these fintech-endogenous markets.The suggested value proposition is investigated by means of an empirical literature review, and partial recreation of some key findings from previous literature.Subsequently, additional empirical findings are contributed through a comparative set of tests in a controlled environment, with some significant results, specifically in the case where an appropriate trading strategy is back-tested along with some neural network forecasting procedures.The implications for researchers and practitioners are emphasised by a re-contextualisation of how the findings could affect future research in forecasting-and trading methodologies as well as the status quo of portfolio management strategies that risk managers have at their disposal.They key contribution is that risk managers should be able to benefit from the erratic behaviour of fintech-endogenous markets in the form of non-negligible short-term abnormal profit, whilst not having to trade off the diversification properties consistent with the established literature.The junction of forecasting-and trading methodologies used here may result in a "best of both worlds" investment strategy where abnormal profits are possible in the short run, in a simultaneously well-hedged trading environment, which relies on (instead of mitigating) the erratic price-formation phenomena prevalent in fintech-endogenous markets.
Smart contracts are the most important feature in block chain applications, and they are also the main reason why blockchains are called disruptive technology. Traditional intelligent contracts with receipts are generated by SHA-256A UXTO (unexpended transaction output), and increasing the number of receipts slows down the speed. This paper introduces the operation of receipts in smart contracts and proposes to generate contract receipts with the VIF virtual iteration function. VIF takes advantage of the excellent features of the Hash function and the unreadable nature of the self-compiled system, so that different contract parameters generate unique and non-repudiation receipts through the virtual iterative function, providing a secure and reliable credential for smart contracts. Finally, the speeds at which the VIF receipt and traditional UXTO receipt are generated are compared.
This thesis in Industrial Engineering and Management examines which the critical success factors are for implementing blockchain technology in the context of trade finance. Blockchain is an up-and-coming technology that has yet not been implemented in many organizations. By examining which the success factors are for implementing the technology, a foundation can be provided for future implementation efforts with the hope of achieving a successful result. Furthermore, to assess if an implementation of blockchain has been successful or not, the value of it has been assessed. Through a qualitative study with interviewees from both companies acting in the trade finance industry and experts on the subject of blockchain, information could be gathered in order to confirm the theoretical framework as well asprovide for new findings. The conclusion was that the most important success factors for implementing blockchain, found in the theoretical framework were: "Managing and involving stakeholders (for instance customers and suppliers)", "Clear management support/commitment/involvement of the implementation",and "Understanding of the organization in which the implementation is to take place (its strengths, needs,etc.)". The least important factors proved to be "An in depth understanding of the technology that is to be implemented; what it is and how it works", "Keeping the change communicable and transparent within the organization", and "Extensive project definition and planning". Unexpected findings were that almost all interviewees mentioned that there has to be a real need for the technology in order for it to be successfully implemented. Also, as the very nature of blockchain requires cooperation; it is important to realize that blockchain will require a higher degree of working over organizational boundaries. Another aspect that proved to be important to take into consideration is that the trade finance industry holds legacyand therefore is prone to be resistance to change, especially to a technology of such a highly disruptive character. Lastly, it is of importance to mention that the context also has to be taken into consideration;every organization is different and require different approaches when it comes to implementing blockchain technology. When it comes to how blockchain technology generates value from an organizational perspective, the most common answers were that it enhances collaboration and trust. Many identify value in the problem-solving and more decentralized mindset that blockchain brings. An unexpected finding was that the mere use of the word blockchain will create value, as this enables collaboration and investment. Other reasons given were security, transparency, automation, traceability,and decentralization. Further analysis examined the reasons behind the importance and connection of these answers.
Currently, a large range of opinions exists regarding the appropriate classification and regulation of cryptocurrency. From the legal perspective, some suggest that cryptocurrency investments are too speculative. As a result of this, it is suggested that cryptocurrency should be more heavily regulated. This would be done to prevent speculators from losing vast wealth. Other legal analysts suggest that an increasing cryptocurrency regulation would have a detrimental effect on the state of cryptocurrency, and its use would cause long-term problems. From the accounting perspective, opinions vary. Some suggest an accounting classification that would make cryptocurrency cash equivalents; others suggest an accounting classification that would render cryptocurrency an intangible asset with an indefinite useful life. The โbig 4โ accounting firms that include Deloitte, PricewaterhouseCoopers, Ernst and Young, and KPMG recommend that cryptocurrency should be classified as an intangible asset with an indefinite useful life. However, other companies currently using cryptocurrency through the general operations of the business have decided to classify it differently. The legal perspectives and the accounting perspectives will be analyzed to determine appropriate regulations for cryptocurrency and an appropriate classification for cryptocurrency. The results will show that cryptocurrency should be classified as an intangible asset with an indefinite useful life for accounting purposes and as property for tax purposes.
Since its inception, bitcoin has occupied a prominent role in the cryptocurrency market. As bitcoin received increased attention, researchers have examined popular sentiment as a predictor of bitcoin price fluctuation. However, the popular sentiment may differ from the sentiment of financial professionals. We ask whether the presence and news sentiment from prestigious business journals would affect the bitcoin return. We collected the daily bitcoin price data from 01/01/2017 to 03/31/2018 from the third-party cryptocurrency exchange website CoinMarketCap. The headlines of news mentioning bitcoin on Wall Street Journal and Financial Times are collected from LexisNexis Database. We calculated the sentiment embedded in the news headlines using a bag-of-words model and a dictionary-based approach. We estimate a regression of financial news sentiment on bitcoin daily return. Our main findings are that positive sentiment contributes significantly negatively to bitcoin return on the same day; negative sentiment day contributes positively, although not significantly. We interpret these findings through the disposition effect that, investors tend to sell high-performed assets and hold underperformed assets. The findings extend our understanding of disposition effect to the cryptocurrency market, and we plan to further examine if there is evidence of the disposition effect.
After the 4th industrial revolution, the healthcare industry is striving to find new business models through new technologies. Among them, blockchain technology is one of the technologies that have great interest in the healthcare industry. Most providers of personal health record systems have difficulty in securing marketability due to various problems. Therefore, they try to integrate blockchain technology to develop new systems and gain marketability. However, blockchain has limitations in solving the problems of the personal health record system. In this study, we have designed a personalized health data management framework that enables information subjects to acquire full ownership rights of individualโs health data, based on distributed ledger technology. For the framework design, we refer to the structure of R3 Corda. It was designed with a different network structure than the existing blockchain systems so that the node can be operated on the personal user's mobile device. This allows information subjects to directly store and manage their own data and share data with authorized network members. Through the proposed system, the information utilization of the healthcare industry can be improved and the public health promotion and medical technology development can be realized.
Blockchain has become another new information revolution after the Internet, and to a certain extent, like the Internet, will change the existing production relations and business logic. With the advent of blockchain, smart contracts have become one of the most sought-after technologies. Its high customizability becomes the key to implement blockchain technology in multiple fields ranging from financial services, life sciences and healthcare to energy resources and voting. However, due to the infancy, challenges are put forward as smart contracts widespread deployment. This study aims to contribute a comprehensive overview on smart contract within blockchain technology. Based on systematic mapping study, we offer a broad perspective of current academic research and application areas of smart contracts. First, by using bibliometric mining on 158 smart contract-related papers, we identified publication profiles, research hot trends and research topic clustering. Then, we provide a summary of the areas where smart contracts are used and analyze the pain points, they address. Finally, we identify the bottlenecks that need to be broken and propose research outlook for the future development of this topic. This paper is aimed at providing helpful guidance and reference for future research efforts.
Ubiquitous sensing enabled by Wireless Sensor Network (WSN) technologies cuts across many areas of modern day living.This offers the ability to measure, infer and understand environmental indicators, from delicate ecologies and natural resources to urban environments.The proliferation of these devices in a communicating-actuating network creates the Internet of Things (IoT), wherein, sensors and actuators blend seamlessly with the environment around us, and the information is shared across platforms in order to develop a common operating picture (COP).Fuelled by the recent adaptation of a variety of enabling device technologies such as RFID tags and readers, near field communication (NFC) devices and embedded sensor and actuator nodes, the IoT has stepped out of its infancy and is the next revolutionary technology in transforming the Internet into a fully integrated Future Internet.As we move from www (static pages web) to web2 (social networking web) to web3 (ubiquitous computing web), the need for data-on-demand using sophisticated intuitive queries increases significantly.This paper gives very interesting understanding with IoT discussed with making as simple as possible not with the intention to reach concept only up to readers but to become understandable and friendly at students level with some text and basic models.