With development of Big Data technology these years, Internet financial companies in China started trying using big data technology to do credit investigation instead of traditional methods. But there is some limitation and problem in terms of data acquisition channel, information asymmetry and data privacy protection, etc. Block chain, characterized in unalterability and decentralization comes into people's sight. This paper will introduce block chain technology, explore the use of block chain technology in Internet financial credit investigation, and put forward an internet financial credit data sharing model based on block chain, which mainly composed by the Fin-tech Federate Servers group (FFS), the user data storage structure and a distributed database system (DDBS). By combining DPoS and re-encryption technology, the model has the characteristics of non-tampering, authorized access and convenient accountability. Through this model, the user data is recorded by the trusted agent, encrypted by asymmetric encryption technology, and anchored to the chain of the block periodically.
Siti Rohaya Mat Rahim, Zam Zuriyati Mohamad, Juliana Abu Bakar, Farhana Hanim Mohsin · 5 authors
This study examines the two important aspect of latest technology issues in Islamic finance that related to artificial intelligence (AI) and smart contract. AI refers to the ability of machines to understand, think, and learn in a similar way to human beings, indicating the possibility of using computers to simulate human intelligence. Smart contract is a computer code running on top of a block-chain containing a set of rules under which the parties to that smart contract agree to interact with each other. The main objectives of this article are to evaluate the operations of AI and smart contract, to make comparison between the operations of AI and smart contract. This article concludes that AI and smart contract will have a huge impact in future for Islamic Finance industry.
Purpose The purpose of this paper is to examine the value-at-risk and related measures for the Bitcoin and to compare the findings with Standard and Poor’s SP500 Index, and the gold spot price time series. Design/methodology/approach A GJR-GARCH model has been implemented, in which the residuals follow the standardized Pearson type-IV distribution. A large variety of value-at-risk measures and backtesting criteria are implemented. Findings Bitcoin is a highly volatile currency violating the value-at-risk measures more than the other assets. With respect to the Basel Committee on Banking Supervision Accords, a Bitcoin investor is subjected to higher capital requirements and capital allocation ratio. Practical implications The risk of an investor holding Bitcoins is measured and quantified via the regulatory framework practices. Originality/value This paper is the first comprehensive approach to the risk properties of Bitcoin.
The emergence of a cryptocurrencies in the economic circulation is a challenge for legal systems. The response of a legal system depends on social, political and international determinants. The first attempts to understand cryptocurrencies usually concerns tax law, which, however, are related to the civilian understanding of the phenomenon. In the Polish legal system, we had a lack of regulation directly related to cryptocurrencies, which caused them to be strictly qualified as an instrument whose exchange for money was not exempt from VAT as Bitcoin was not classified as money. This situation has changed as a result of the case law of the Court of Justice of the European Union, which has recognized Bitcoin as an alternative means of payment. Recently, new statutory regulations have been introduced in non-European legal systems, i.e. in Japan and Arizona, which regulate cryptocurrencies in a wider way. This allows us to propose classification of legal systems based on the relationship they have towards cryptocurrencies.
This paper investigates the power of quantum statistical zero knowledge interactive proof systems in the relativized setting. We prove the existence of an oracle relative to which quantum statistical zero-knowledge does not contain UP intersect coUP, and we prove that quantum statistical zero knowledge does not contain UP relative to a random oracle with probability 1. Our proofs of these statements rely on a bound on output state discrimination for relativized quantum circuits based on the quantum adversary method of Ambainis, following a technique similar to one used by Ben-David and Kothari to prove limitations on a query complexity variant of quantum statistical zero-knowledge.
Sepsis is a high mortality syndrome characterized by organ dysfunction due to a severe and dysregulated acute inflammatory response to infection. Research into therapies for this syndrome has historically ended in failure, which has largely been attributed to the elevated levels of subject heterogeneity. What may have been previously attributed to variability in sepsis may be due to mechanistic differences between patients. Endotypes are distinct subtypes of disease, where underlying causes such as mechanistic or pathway related differences manifest into phenotypes of disease. The lack of mechanistic understanding of immune mediator dynamics and the responses they trigger necessitates a mathematical modeling approach to analyze its complexities. A transfer function model is proposed to describe and cluster the dynamics of key inflammatory mediators. Five sepsis endotypes were discovered and revealed motifs of overwhelming inflammation, various levels of immunosuppression, sustained inflammation, and immunodeficiency. An accurate clinical tool was proposed to classify subjects into endotypes using six-hour trajectories of clinical data. A physiological ordinary differential equation model of sepsis is proposed that characterizes the interactions of inflammatory signaling molecules, neutrophils, and macrophages across the bone, blood, and tissue compartments of the body. This model used to generate individual subject fits against human sepsis data. Population-level parameter analysis implicated macrophage cell death and cytokine half- dynamics in endotype-level differences. Several proof-of-concept statistical models were introduced to demonstrate that it is possible to estimate the pre-hospital time of sepsis subjects and to quantify their sepsis-induced systemic tissue damage. A nearest-neighbor-based method was verified against animal and human data and revealed that identifying infection time-zero of sepsis patients can be quickly estimated with high accuracy using commonly measured clinical features. A logistic regression ensemble model demonstrated revealed early organ dysfunction were significant contributors to systemic damage and mortality. Knowledge of time-zero and systemic damage levels, in combination with an endotype classifier, provides clinicians with a clear depiction of where a subject is located on their sepsis trajectory. Such a decision support system enables therapy timing, early organ support, and targeted therapies to guide personalized treatment and shift patients towards better outcomes in sepsis.
Bitcoin is a peer-to-peer electronic currency without central bank controlling. Nowadays, increasing amount of people are engaged in the mining of Bitcoin for great profits. However, in the Bitcoin system, the more participants in the system, the greater computation power of the whole network and the less efficiency in the output of the coin, since large computational power of the whole Bitcoin system will lead to increased difficulty for a single miner to mine a new data block. At the same time, when more than 51% computing power is controlled by a single node, it could destroy the Bitcoin system. In order to reduce ineffective mining behaviors, one would wish to employ the optimal selection mechanism of different miners. This paper will mainly develop the model in which small miners (those who have relative smaller computational power in a block mining) join the major ones based on revenue, computational power cost, and other elements of the process comparing to the current model (when they work separately).
Higher education in India has expanded rapidly over the past two decades. This growth has been mainly driven by private sector initiatives. There are genuine concerns about many of them being substandard and exploitative. Due to the government’s ambivalence on the role of private sector in higher education, the growth has been chaotic and unplanned. The regulatory system has failed to maintain standards or check exploitation instead, it resulted in erecting formidable entry barriers that have generated underside results. Voluntary accreditation seems to have no takers from amongst private providers and apparently serves little purpose for any of its stakeholders. The higher education system in India grew rapidly after independence. [1] By 1980, there were 132 universities and 4738 colleges in the country enrolling around five percent of the eligible age group in higher education. Today, while in terms enrolment, India is the third largest higher education system in the world (after China and the USA) with 17973 institutions (348 universities and 17625 colleges) and is the largest higher education system in the world in terms of number of institutions [2] There are different types of universities and colleges in the higher education system in the country. They vary terms of their academic, administrative and financial arrangements. Universities can either be established by an Act of Parliament or by the state legislatures. Those established by the Act of Parliament are the central universities and the ones set up by the state legislatures are state universities. Some higher education institutions are granted the ‘deemed university’ status by the central government through gazette notifications. A few institutions are established by the Parliament / state legislatures as institutions of national importance. Universities, deemed universities and institutions of national importance are degree-granting institutions. The expansion of higher education system in India has been chaotic and unplanned. The drive to make higher education socially inclusive has led to a sudden and dramatic increase in numbers of institutions without a proportionate increase in material and intellectual resources. As a result, academic standards have been jeopardized. There are many basic problems facing higher education in India today. These include inadequate infrastructure and facilities, large vacancies in faculty positions and poor faculty outmoded teaching methods, declining research standards, unmotivated students, overcrowded classrooms and widespread geographic, income, gender and ethnic imbalances. There is an inadequate and diminishing financial support for higher education from the government and from society. Many colleges established in rural areas are non-viable, are under enrolled and have extremely poor infrastructure and facilities with just a few teachers. Apart from these, the system of higher education has met several setbacks with regard to its regulatory framework, finding and frances and the much debated and controversial move of privatization of higher educational institutions. These underlying issues will be identified and addressed in the paper. Keywords—Higher Education, India. Research methodology A. Aims and Objectives The objectives of this paper is to identify the major issues and problems relating to the system of higher education in India. The researcher has narrowed down the scope of this paper to three main concerns relating to higher education viz., the present regulatory framework, and privatization and funding and financing. The paper examines various arguments, cases and recommendations in highlighting the issues concerned. B. Scope and Limitations The scope of this paper is limited to the identification and study of the major issues concerning the Indian higher education system. C. Mode of Citation A uniform mode of citation is used throughout the paper. D. Sources of Data This paper is based on researched complied from numerous articles, working papers, statistical data and case laws. E. Research Questions The following questions are sought to be addressed in the course of this paper : What are the major issues and problems affecting higher education in India ? Why is the existing regulatory mechanism problematic for the growth and development of higher education in the country ? How can student loans help in improving the accessibility of higher education? How can the issues discussed in the paper be addressed to resolve the existing conflicts ? F. Chapterization The paper is divided into three broad chapters : Chapter 1: The problems with the existing regulatory framework are identified along with a discussion of the recommendations of various committee. Chapter 2: This chapter deals with the issue of privatization of higher education in India. Chapter 3: The decline in public expenditure on higher education and the inextricable link between the present regulations and funding/finances of educational institutions is examined in the last chapter. II. CONCLUSION Government regulation of higher education has been the subject of an acrimonious debate across the policy spectrum. Proponents argue that regulation is essential for delivering quality education. Without regulation, they further argue, profit maximization rather than education would be the raison deter of private education institutions. In their opinion, the abysmal quality of most private institutions-despite decades of stifling regulations-justifies more government intrusion; not private institutions-despite decades of stifling regulations-justifies more government intrusion; non less, it is perceived to be State’s responsibility to protect those who avail of higher education. The inability to incentives quality in private institutions of higher learning is the key failure of India’s education regulators. Rather than improving quality, the state’s stranglehold on higher education has created an artificial shortage leading to an acute supply-demand mismatch. The demand for higher educational institutions then the growth in number of higher educational institutions. The regulatory process is thoroughly politicized; it is well documented that most private colleges are owned by politicians or well-connected business houses. The poor quality of such institutions offers a readymade excuse to impose even stronger government regulations, notwithstanding the fact that high entry barriers-ostensibly erected to improve quality of such institutions to thrive in the first place. While the regulatory bodies seek to guard the portals of higher education, and are entrusted with the responsibility of ensuring adherence to minimum guidelines by existing institutions, however, these regulations. In their current form are simply erecting entry-barriers rather than working to remove the asymmetry. Regulation, therefore, needs to be well structured and thoroughly researched to take full account of relevance, therefore, needs to be well structured and thoroughly researched to take full account of relevance, requirement, practical constraints and market realities. The objective of encouraging growth of educational institutions rather than restricting them should not be lost sight of higher education offers a wide variety of subjects and with continuing education it needs to be demand driven. Over the last few decades, higher education has been handled casually and, for the most part, is lacking in initiative or direction. In addition to this, the process of accreditation remains a strenuous bureaucratic exercise. While the bogus or poor quality colleges are a matter of concern for every regulator, the problem in India is that University Authorities do not have a proper monitoring and surveillance system for colleges. This leads to episodes of sudden de-recognition as in the case of Chattisgarh University an a large number of affiliated colleges which was very distressing for a large number of students. Another important measure to be undertaken is that of decentralization. The purpose of decentralization is to eliminate or reduce the cumbersomeness and inefficiency, to convert high costs per unit into low costs and replace diseconomies of scale. In the absence of decentralization, the introduction of new techniques becomes meaningless as the already over expanded monolithic system does not leave any room for improvement.
While cryptocurrencies and blockchain applications continue to gain popularity, their energy cost is evidently becoming unsustainable. In most instances, the main cost comes from the required amount of energy for the Proof-of-Work, and this cost is inherent to the design. In addition, useless costs from discarded work (e.g., the so-called Forks) and lack of scalability (in number of users and in rapid transactions) limit their practical effectiveness. In this paper, we present an innovative scheme which eliminates the nonce and thus the burden of the Proof-of-Work which is the main cause of the energy waste in cryptocurrencies such as Bitcoin. We prove that our scheme guarantees a tunable and bounded average number of simultaneous mining whatever the size of the population in competition, thus by making the use of nonce-based techniques unnecessary, achieves scalability without the cost of consuming a large volume of energy. The technique used in the proof of our scheme is based on the analogy of the analysis of a green leader election. The additional difference with Proof-of-Work schemes (beyond the suppression of the nonce field that is triggering most of the waste), is the introduction of (what we denote as) "empty blocks" which aim are to call regular blocks following a staircase set of values. Our scheme reduces the risk of Forks and provides tunable scalability for the number of users and the speed of block generation. We also prove using game theoretical analysis that our scheme is resilient to unfair competitive investments (e.g., "51 percent" attack) and block nursing.
he article presents the characteristic of the scientific genesis of public risk management in construction in Ukraine, in global and local dimen- sions. The essence of the working organization of risk management in the con- struction and operation of buildings, taking into account the transformational processes in society, is disclosed. On the basis of the analysis of risks in construc- tion and taking into account the current realities, scientifically grounded ap- proaches to the formation of the risk system in the construction and operation of facilities in the system of public administration. It is noted that the risks and crisis phenomena in the construction complex gave a powerful impetus to un- derstanding the causes of the problems of decentralization and finding mecha- nisms for their elimination, in general. The trilateral mission of the state in the conditions of decentralization is the regulation of the macroeconomic role of the construction complex, the mechanism of economic relations of its participants, and ensuring the effectiveness of design decisions in the construction sector, by extending their competences on prevention and risk reduction in the construction industry by the local self-government bodies. To form a state decentraliza- tion policy for construction is required on the basis of knowledge of objective regional macro- and microeconomic investment-construction processes in ci- ties, economic mechanism and indicators of development of investment-build- ing complex and dynamics of social and economic development of regions. The mechanism of the construction complex needs to be improved, using new sources and forms of financing, achieving the balance of the goals of decentralization and its financial support. In addition, taking into account the European integration course of the announced reforms, the European understanding of the essence of risk management in construction during decentralization becomes of paramount importance. Therefore, further research requires the study of the experience of European countries in the implementation of risk management processes in con- struction during the decentralization of power and the analysis of foreign systems of management mechanisms, in the context of their implementation in the na- tional practice of public administration.
N.I. Indera, Ahmad Ihsan Mohd Yassin, Azlee Zabidi, Zairi Ismael Rizman
This paper presents a Multi-Layer Exogeneous Inputs (NARX) Bitcoin price forecasting model using the opening, closing, minimum and maximum past prices together with Moving Average (MA) technical indicators.
As we observe a trend towards the recentralisation of the Internet, this paper raises the question of guaranteeing an everlasting decentralisation. We introduce the properties of strong and soft uncentralisability in order to describe systems in which all authorities can be untrusted at any time without affecting the system. We link the soft uncentralisability to another property called perfect forkability. Using that knowledge, we introduce a new cryptographic primitive called uncentralisable ledger and study its properties. We use those properties to analyse what an uncentralisable ledger may offer to classic electronic voting systems and how it opens up the realm of possibilities for completely new voting mechanisms. We review a list of selected projects that implement voting systems using blockchain technol- ogy. We then conclude that the true revolutionary feature enabled by uncentralisable ledgers is a self-sovereign and distributed identity provider.
Consensus protocols inherently rely on the notion of leader election, in which one or a subset of participants are temporarily elected to authorize and announce the network's latest state. While leader election is a well studied problem, the rise of distributed ledgers (i.e., blockchains) has led to a new perspective on how to perform large-scale leader elections via solving a computationally difficult puzzle (i.e., proof of work). In this paper, we present Caucus, a large-scale leader election protocol with minimal coordination costs that does not require the computational cost of proof-of-work. We evaluate Caucus in terms of its security, using a new model for blockchain-focused leader election, before testing an implementation of Caucus on an Ethereum private network. Our experiments highlight that one variant of Caucus costs only $0.10 per leader election if deployed on Ethereum.
In this article, I shall examine the compatibility of Bitcoin and other cryptocurrencies within the context of Islamic law. I shall begin by an introduction of Bitcoin and other cryptocurrencies. I will then discuss the history of money in Islamic history, with an emphasis on the importance ethical financial dealings. I will then argue that Bitcoin and other cryptocurrencies are highly compatible within Islamic finance, and in many cases, actually provide solutions to problems of government institution controlled currencies, arguing that Bitcoin and other cryptocurrencies better address several problems that early Islamic finance scholars were concerned with. Unlike traditional fiat, the supply of Bitcoin and many other digital currencies are fixed, thereby eliminating potential for gharar (deception), and also inflation. In addition, unlike fiat and precious metal coins, digital currencies cannot be altered, forged, or manipulated. Moreover, cryptocurrencies’ peer-to-peer transactions remove the need for any banking institution, thereby eliminating any risk with a third party controlling one’s money. I shall then conclude with a summary of the main points of the article, and examine future possibilities with regards to the role of digital and cryptocurrencies.
Hélder Sebastião, António Portugal Duarte, Gabriel Guerreiro
This paper analyses the price discovery in the USD/Bitcoin market since Mar‑2014 to Nov‑2016. The results show a positive relationship between the informational relevance of exchanges and their market shares. Information is mostly transmitted between exchanges within an hour, at least for the main exchanges, although lagged feedbacks occur from the major exchanges. Minor exchanges are merely satellite ones and react to price information with some delay. Bitfinex is the most important exchange: the lagged feedback from this exchange to the market is 18.3%, while the reverse feedback accounts only for 0.6% of the total feedback. Volatility in the major exchanges is the main factor explaining the feedback measures, which sustains the claim that the relative importance of the information-based component of volatility increases with the relative dimension of the exchange.
Husam Al Jawaheri, Mashael Al Sabah, Yazan Boshmaf, Aiman Erbad
With the rapid increase of threats on the Internet, people are continuously seeking privacy and anonymity. Services such as Bitcoin and Tor were introduced to provide anonymity for online transactions and Web browsing. Due to its pseudonymity model, Bitcoin lacks retroactive operational security, which means historical pieces of information could be used to identify a certain user. We investigate the feasibility of deanonymizing users of Tor hidden services who rely on Bitcoin as a payment method by exploiting public information leaked from online social networks, the Blockchain, and onion websites. This, for example, allows an adversary to link a user with @alice Twitter address to a Tor hidden service with private.onion address by finding at least one past transaction in the Blockchain that involves their publicly declared Bitcoin addresses.
To demonstrate the feasibility of this deanonymization attack, we carried out a real-world experiment simulating a passive, limited adversary. We crawled 1.5K hidden services and collected 88 unique Bitcoin addresses. We then crawled 5B tweets and 1M BitcoinTalk forum pages and collected 4.2K and 41K unique Bitcoin addresses, respectively. Each user address was associated with an online identity along with its public profile information. By analyzing the transactions in the Blockchain, we were able to link 125 unique users to 20 Tor hidden services, including sensitive ones, such as The Pirate Bay and Silk Road. We also analyzed two case studies in detail to demonstrate the implications of the resulting information leakage on user anonymity. In particular, we confirm that Bitcoin addresses should always be considered exploitable, as they can be used to deanonymize users retroactively. This is especially important for Tor hidden service users who actively seek and expect privacy and anonymity.
Blockchains enables tamper-proof, ordered logging for transactional data in a decentralized manner over open-access, overlay peer-to-peer networks. In this paper, we propose a decentralized framework of proactive caching in a hierarchical wireless network based on blockchains. We employ the blockchain-based smart contracts to construct an autonomous content caching market. In the market, the cache helpers are able to autonomously adapt their caching strategies according to the market statistics obtained from the blockchain, and the truthfulness of trustless nodes are financially enforced by smart contract terms. Further, we propose an incentive-compatible consensus mechanism based on proof-of-stake to financially encourage the cache helpers to stay active in service. We model the interaction between the cache helpers and the content providers as a Chinese restaurant game. Based on the theoretical analysis regarding the Nash equilibrium of the game, we propose a decentralized strategy-searching algorithm using sequential best response. The simulation results demonstrate both the efficiency and reliability of the proposed equilibrium searching algorithm.
Husam Al Jawaheri, Mashael Al Sabah, Yazan Boshmaf, Aiman Erbad
With the rapid increase of threats on the Internet, people are continuously seeking privacy and anonymity. Services such as Bitcoin and Tor were introduced to provide anonymity for online transactions and Web browsing. Due to its pseudonymity model, Bitcoin lacks retroactive operational security, which means historical pieces of information could be used to identify a certain user. We investigate the feasibility of deanonymizing users of Tor hidden services who rely on Bitcoin as a payment method by exploiting public information leaked from online social networks, the Blockchain, and onion websites. This, for example, allows an adversary to link a user with @alice Twitter address to a Tor hidden service with private.onion address by finding at least one past transaction in the Blockchain that involves their publicly declared Bitcoin addresses. To demonstrate the feasibility of this deanonymization attack, we carried out a real-world experiment simulating a passive, limited adversary. We crawled 1.5K hidden services and collected 88 unique Bitcoin addresses. We then crawled 5B tweets and 1M BitcoinTalk forum pages and collected 4.2K and 41K unique Bitcoin addresses, respectively. Each user address was associated with an online identity along with its public profile information. By analyzing the transactions in the Blockchain, we were able to link 125 unique users to 20 Tor hidden services, including sensitive ones, such as The Pirate Bay and Silk Road. We also analyzed two case studies in detail to demonstrate the implications of the resulting information leakage on user anonymity. In particular, we confirm that Bitcoin addresses should always be considered exploitable, as they can be used to deanonymize users retroactively. This is especially important for Tor hidden service users who actively seek and expect privacy and anonymity.
Rhys Bowden, Paul Keeler, A. E. Krzesinski, Peter Taylor
Bitcoin is a electronic payment system where payment transactions are verified and stored in a data structure called the blockchain. Bitcoin miners work individually to solve a computationally intensive problem, and with each solution a Bitcoin block is generated, resulting in a new arrival to the blockchain. The difficulty of the computational problem is updated every 2,016 blocks in order to control the rate at which blocks are generated. In the original Bitcoin paper, it was suggested that the blockchain arrivals occur according to a homogeneous Poisson process. Based on blockchain block arrival data and stochastic analysis of the block arrival process, we demonstrate that this is not the case. We present a refined mathematical model for block arrivals, focusing on both the block arrivals during a period of constant difficulty and how the difficulty level evolves over time.
Vehicular Ad Hoc Networks (VANETs) play a vital role in enabling smart transportation systems by facilitating communication between vehicles. However, existing vehicular announcement systems face two major challenges: preserving user privacy and motivating users to share reliable traffic information. In this paper, we propose CreditCoin, a privacy-presing blockchain-based incentive announcement network. The system utilizes an anonymous vehicular announcement aggregation protocol combined with blockchain technology to ensure secure, tamper-resistant, and decentralized communication. Users can broadcast traffic updates anonymously while earning incentives for participation, thereby improving network reliability. A Trace Manager enables conditional privacy by identifying malicious users without compromising honest participants. The proposed system is implemented using Python, Web3, and a simulated VANET environment. Experimental results demonstrate improved efficiency, reduced computation time, and enhanced data reliability compared to traditional approaches. This work contributes toward secure and incentive-driven communication in smart transportation systems. In this paper, we propose CreditCoin, a privacy-preserving blockchain-based incentive announcement network. The system utilizes an anonymous vehicular announcement aggregation protocol combined with blockchain technology to ensure secure, tamper-resistant, and decentralized communication. Users can broadcast traffic updates anonymously while earning incentives for participation, thereby improving network reliability. A Trace Manager enables conditional privacy by identifying malicious users without compromising honest participants. Keywords— VANET; Blockchain; Privacy Preservation; Incentive Mechanism; Smart Vehicles; CreditCoin
Bitcoin and other similar digital currencies on blockchains are not ideal means for payment, because their prices tend to go up in the long term (thus people are incentivized to hoard those currencies), and to fluctuate widely in the short term (thus people would want to avoid risks of losing values). The reason why those blockchain currencies based on proof of work are unstable may be found in their designs that the supplies of currencies do not respond to their positive and negative demand shocks, as the authors have formulated in our past work. Continuing from our past work, this paper proposes minimal changes to the design of blockchain currencies so that their market prices are automatically stabilized, absorbing both positive and negative demand shocks of the currencies by autonomously controlling their supplies. Those changes are: 1) limiting re-adjustment of proof-of-work targets, 2) making mining rewards variable according to the observed over-threshold changes of block intervals, and 3) enforcing negative interests to remove old coins in circulation. We have made basic design checks and evaluations of these measures through simple simulations. In addition to stabilization of prices, the proposed measures may have effects of making those currencies preferred means for payment by disincentivizing hoarding, and improving sustainability of the currency systems by making rewards to miners perpetual.