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53,014 results · page 1831 of 2,209
Yongping Zhang, Pengyuan Zhang, Fei Tao, Yang Liu · 5 authors
No abstract is available for this record.
Ann Ogbo, Anthony Igwe, Jesse Ezeobi, Nwanneka J. Modebe · 5 authors
This paper examined the impact of social entrepreneurship on sustainability of business development in Nigeria. The objectives of the study include: to identify major evolution experienced by social enterprise in Nigeria, to identify key challenges in social entrepreneurship in Nigeria, to identify current trends in social entrepreneurship in Nigeria, and to carry out an analysis on sources of funds for financing the social entrepreneurs. Survey approach was the research design used with particular reference to selected small and medium enterprises (SME) in Nigeria. It was observed that political factors, economic factors, socio-cultural factors, cross country factors and technological factors are the major evolution experienced by social enterprise in Nigeria. It was also observed that lack of education in entrepreneurship, lack of financial assistance, comparative disadvantages to business, lack of government support and lack of skilled manpower are the key challenges in social entrepreneurship in Nigeria. The current trends in social entrepreneurship in Nigeria are social media and the role of technology, rise of decentralized micro-giving opportunities, cross-sector partnerships and government drive for an all-inclusive economic growth and development through SME. The analysis carried out on sources of funds for financing the social entrepreneurs are contributions from social entrepreneurs, subventions from government, donor supports, loans and advances and retained earnings/reserves.
Camilla Muglia, Luca Santabarbara, Stefano Grassi
The paper investigates whether Bitcoin is a good predictor of the Standard & Poor’s 500 Index. To answer this question we compare alternative models using a point and density forecast relying on Dynamic Model Averaging (DMA) and Dynamic Model Selection (DMS). According to our results, Bitcoin does not show any direct impact on the predictability of Standard & Poor’s 500 for the considered sample.
Mrs. Divya K V
I. INTODUCTION Blockchain technology was first introduced as Bitcoin's underlying technology but soon later its extendable capabilities have been recognized. The peer-to-peer cryptocurrency, Bitcoin, is a core innovation in the financial sector nowadays. Its underlying technology, blockchain, is a type of a distributed ledger especially suitable for processing time ordered data. In addition, embedded cryptography functions of blockchain technology enable integrity of ledgers, authenticity of transactions, and privacy of transactions without a centralized control actor. Those make the blockchain different from traditional distributed database systems being used in the financial sector, e.g., it is practically impossible to modify or delete records of a ledger in the blockchain. This distributed and decentralized nature of the blockchain has attracteded financial institutions over the world to replace existing backbone technologies with blockchain technology. Blockchain keeps a record of all data exchanges -this record is referred to as a "ledger" in the cryptocurrency world, and each data exchange is a "transaction". Every verified transaction is added to the ledger as a "block" It utilizes a distributed system to verify each transaction -a peer-to-peer network of nodes. Once signed and verified, the new transaction is added to the blockchain and cannot be altered In the cryptocurrency world, your wallet address represents public key and your private key is what let's you authorize transfers, withdrawals, and other actions with your digital property like cryptocurrencies. As an aside, this is why it's so important to keep your private key safe -anyone who has your private key can use it to access any of your digital assets associated with your public key and do what they want with it! Each transaction in that ledger will have the same data: a digital signature, a public key, a timestamp, and a unique ID. For instance, the logistics sector considers blockchain technology for real-time visibility, improved efficiency, transparency, verifiability, and cost reduction for logistics. The property sector is adopting blockchain technology as well for digital but unforgeable property records, few disputes, transparency, verifiability, and lower transfer fees. The food sector is also investing blockchain technology to trace the movements of foods and tackle contamination faster.
Juan Holgado Barroso
This article proposes an evolutionary study of a basic institution in regional educational administration within the boundary of the Autonomous Region of Andalusia, The Education Council, within the first stage of its coming into operation. It started with a set up which was typical of the beginning of decentralization derived from the autonomous State and it was characterized by the scarcity of attributions, by how provisional it was and by the effort to endow the Andalusian government with certain importance, until the end of a period that was marked by a reform of the Spanish educational system (LOGSE), with evident administrative and organizational consequences in all the autonomous regions. During the period studied (1982-1990) the Council is ruled by a model of functional “departmenting”, where activities are grouped according to the fundamental duties to be carried out in order to achieve the proposed objectives.
Dela Delen, Pudjiharjo Pudjiharjo, Susilo Susilo
Research on Local Revenue, General Allocation Fund, and Special Allocation Fund on economic growth, poverty, unemployment, and Gini ratios have often been done. However, there is no research that uses these three funding sources as latent variables that have a simultaneous influence on quality economic growth variables as a latent variable consisting of economic growth, poverty, unemployment and the Gini ratio as constructs. Similarly, capital expenditure as a moderating variable will be seen as influencing the source of funds. East Java is a province with 38 districts/cities where the level of economic growth is quite high and even exceeds the level of national economic growth. But the level of poverty, unemployment, and inequality is also very high. This study aims to look at the effect of decentralized funding sources on Quality Economic Growth in East Java. The data used comes from the Directorate General of Financial Balance of the Ministry of Finance in 2012 -2015 for realization's fund, and from the Central Bureau of Statistics for economic growth, poverty, unemployment, and Gini ratios. This study uses Partial Least Squares (PLS) in analyzing data, where quality economic growth becomes endogenous latent variables that are influenced by funding sources as exogenous latent variables and capital expenditure as a moderating variable. The results of the analysis show that the source of funds does not significantly affect quality economic growth even though the direction is positive. Likewise, capital expenditure cannot strengthen the influence of funding sources on quality economic growth. From this research, it is expected that the regional government can reanalyze the allocation of funds and the realization of regional expenditures which are prioritized for public service spending so that the triple track strategy can be implemented properly and achieve quality economic growth.
Nicolae VRANĂ
The Internet of Things paradigm enables various applications in different fields through the exponential increase of devices and sensors. Architecting systems based on Internet of Things concepts is very challenging and has focused mostly on a centralized approach. Decentralized or distributed architectures aren't straightforward concepts for IoT applications, but through the distributed ledger and Blockchain implementations that provide better identification, security and data integrity the fully distributed system architecture can become a reality. Major cloud vendors these days are using edge computing platforms to bring the cloud closer to the device, using a locally centralized system based on edge agents, which can be seen as a partially decentralized module in the full IoT cloud picture. Blockchain allows this edge IoT environment to become distributed if services or functions installed on the edge agent are used by the device to gain Blockchain capabilities. If more capable devices are deployed, then the Blockchain functionality can be embedded in the IoT and the system becomes a fully distributed peer-to-peer network.
Najneen Shaikh, Suheb Shaikh, Gyankamal J. Chhajed
Counterfeit of medicine is major problem for consumer. Though there are more conventional methods for identifying counterfeit of medicine but they lack in security so to overcome this problem we are proposing secure software for medicine manufacturing supply chain management system by using blockchain technology. Blockchain technology is specially used in bitcoin cryptocurrency. It is characterized as an open-source, decentralized, distributed database for storing medicine information. Instead of relying on centralized intermediaries, this technology allows two parties to transact directly using duplicate, linked ledger called blockchain. Supply chain management is collection of activities required to plan, control and execute a products flow, from collecting raw materials and production through distribution to the final customer, in the most smooth and cost effective way possible. Supply Chain is beneficial when consumer or the organizations who want the information about medicine manufacturing at every stage to compare its quality. Confidential information related to medicine manufacturing is not to be unveil is accessible to authorized users.
Dominic Bucerzan, Crina Anina Bejan
Today industry, economy and society is reshaped by emergent technologies like "the third web" also known like distributed ledgers technology or blockchain. It seems that the second era of digital economy begun, introducing new concepts like: blockchain, cryptocurrencies, distributed economy and cryptoeconomics. This article aims to propose an image of the actual state of cryptoeconomics, discussing its present and future implications like a research field and proposing several future trends of development.
M. M. Dolgieva
The paper considers the opinions of domestic and foreign authors on the concept of cryptocurrency, the principles of its operation and the need to establish its legal status. The author’s definition of cryptocurrency is formulated and the thesis that cryptocurrency can be classified as «other property» is justified. The author analyzes the most common court decisions in criminal cases. Based on a study of foreign experience in the fight against illegal circulation of cryptocurrency, it was found that initially, before the emergence of mass demand for cryptocurrency all over the world, demand for them was observed in the criminal environment to pay for the supply of narcotic drugs and weapons, to finance terrorism and legalize (launder) income obtained in a criminal manner, in connection with which many people subsequently mistakenly assumed that transactions with cryptocurrencies are anonymous. Meanwhile, the cryptocurrency is far from being anonymous: each transaction carried out in a distributed network is permanently recorded in a public blockchain, which helps to solve crimes in this area. The adoption in the Russian Federation of a fundamental law containing the necessary terms and concepts regarding cryptocurrency activities and regulating the status of cryptocurrency in Russia will further develop measures for the criminal law protection of objects of encroachment that are currently not regulated in any way.
José Miguel Domínguez Jurado, Ricardo García Ruiz
El objetivo de este artículo es explicar cómo un proceso informático, la blockchain o ‘cadena de bloques’, permite generar la confianza necesaria para la creación, la aceptación y el uso cada vez más generalizado de las monedas digitales, bajo un nuevo concepto o paradigma de dinero no sostenido por ningún ente estatal o supranacional: las criptomonedas. Para conocer este proceso, en primer lugar se exponen los aspectos técnicos de funcionamiento de la cadena de bloques y de cómo esta ha conseguido generar confianza en el usuario. En segundo lugar, se analiza su implementación en la más conocida de todas, bitcoin, así como los datos relacionados con la expansión y el uso de las principales criptomonedas, en un mercado que en los últimos dos años se ha multiplicado por 65, alcanzando el medio billón de dólares. El trabajo se cierra exponiendo las principales conclusiones y reflexiones.
Weigandt Consulting, Vladimirovich Toporov Mikhail, Oleg Yurievich Sabinin
This article discusses the possibility of validating the results of the work of the process mining algorithms using consensus algorithms of distributed ledger technology.
Darcy W E Allen, Chris Berg, Sinclair Davidson, Mikayla Novak · 5 authors
Abstract From the adoption of the shipping container to coordinated trade liberalization, reductions in trade costs have propelled modern globalization. In this paper, we analyse the application of blockchain to reduce the trade costs of producing and coordinating trusted information along supply chains. Consumers, producers, and governments increasingly demand information about the quality, characteristics, and provenance of traded goods. Partially due to the risks of error and fraud, this information is costly to produce and to maintain between dispersed parties. Recent efforts have sought to overcome these costs—such as paperless trade agendas—through the application of new technologies. Our focus is on how blockchain technology can form a new decentralized economic infrastructure for supply chains by governing decentralized dynamic ledgers of information about goods as they move. We outline the potential economic consequences of blockchain supply chains before examining policy. Effective adoption faces a range of policy challenges including regulatory recognition and interoperability across jurisdictions. We propose a high‐level policy forum in the Asia‐Pacific region to coordinate issues such as open standards and regulatory compatibility.
Authors unavailable
The new media occupies a wide range of different areas of our daily lives, one of that is the question of national identity and culture. If we focus on the development of the new media and the Internet, we will find that there are many questions and concerns about the Kurdish identity and its culture have come into being, with this development, ringing like bells of dangers, want to alert the media, educational and cultural institutions to do more scientific efforts to study those fears.
Weigandt Consulting, Vladimirovich Toporov Mikhail, Oleg Yurievich Sabinin
This article discusses the theoretical composition of the two consensus algorithms in order to obtain a fundamentally new solution to the problem of consensus in a distributed ledger technologies.
Esther Salmerón-Manzano, Francisco Manzano‐Agugliaro
The advent and development of digital technologies has had a significant impact on the establishment of contracts. Smart contracts are designed as computer code containing instructions for executing user agreements, offering a technologically secure solution with numerous advantages and applications. However, smart contracts are not without their problems when we try to fit them into the traditional system of contract law, and their presumed benefits can become shortcomings. Bibliometric studies can help to assess the current state of science in a specific subject and support decision making and research direction. Here, this bibliometric study is used to analyze global trend research in relation to this novel contractual methodology, the smart contract, which seems to have experienced exponential growth since 2014. Specially, this analysis was focused on the main countries involved and the institutions that lead this research worldwide. On the other hand, the indexations of these works are analyzed according to major scientific areas and the keywords of all the works, to detect the subjects to which they are grouped. Community detection has been used to establish the relationship between countries researching in this area, and six clusters have been identified, around which all the work related to this topic is grouped. This work shows the temporal evolution of research related to smart contracts, highlighting that there are two trends—e-commerce and smart power grids. From the perspective of driving sustainability, smart contracts could provide a contribution in the near future.
Joerg Evermann, Henry Kim
Blockchain technology has been proposed as a new infrastructure technology for a wide variety of novel applications. Blockchains provide an immutable record of transactions, making them useful when business actors do not trust each other. Their distributed nature makes them suitable for inter-organizational applications. However, proof-of-work based blockchains are computationally inefficient and do not provide final consensus, although they scale well to large networks. In contrast, blockchains built around Byzantine Fault Tolerance (BFT) algorithms are more efficient and provide immediate and final consensus, but do not scale well to large networks. We argue that this makes them well-suited for workflow management applications that typically include no more than a few dozen participants but require final consensus. In this paper, we discuss architectural options and present a prototype implementation of a BFT-blockchain-based workflow management system (WfMS).
Victor Cook, Zachary Painter, Christina Peterson, Damian Dechev
Smart contract transactions demonstrate issues of performance and correctness that application programmers must work around. Although the blockchain consensus mechanism approaches ACID compliance, use cases that rely on frequent state changes are impractical due to the block publishing interval of $O(10^1)$ seconds. The effective isolation level is Read-Committed, only revealing state transitions at the end of the block interval. Values read may be stale and not match program order, causing many transactions to fail when a block is committed. This paper perceives the blockchain as a transactional data structure, using this analogy in the development of a new algorithm, Hash-Mark-Set (HMS), that improves transaction throughput by providing a Read-Uncommitted view of state variables. HMS creates a directed acyclic graph (DAG) from the pending transaction pool. The transaction order derived from the DAG is used to provide a Read-Uncommitted view of the data for new transactions, which enter the DAG as they are received. An implementation of HMS is provided, interoperable with Ethereum and ready for use in smart contracts. Over a wide range of transaction mixes, HMS is demonstrated to improve throughput. A side product of the implementation is a new technique, Runtime Argument Augmentation (RAA), that allows smart contracts to communicate with external data services before submitting a transaction. RAA has use cases beyond HMS and can serve as a lightweight replacement for blockchain oracles.
Paolo Giudici, Gloria Polinesi
No abstract is available for this record.
Lyudmila Kovalchuk, Dmytro Kaidalov, Andrii Nastenko, Oleksii Shevtsov · 6 authors
A specific number of transaction confirmation blocks determines average time of receiving and accepting payments at cryptocurrencies, and the shortest confirmation time for the same level of blockchain security provides the best user properties. Existing papers on transaction confirmation blocks for Bitcoin use implicit assumption of prompt spreading of Bitcoin blocks over the network (that is not always the case for the real world conditions). The newer publications with rigorous analysis and proofs of Bitcoin blockchain properties that take into account network delays provide asymptotic estimates, with no specific numbers for transaction confirmation blocks. We propose three methods for determination of required number of confirmation blocks for Bitcoin and GHOST on networks with delayed message delivery with different models that take into account the possibility of faster adversarial node syncronization. For the GHOST we propose the first (to our knowledge) strict theoretical method that allows to get required number of confirmation blocks for a given attacker’s hashrate and attack success probability.
Heba Kurdi, Shada Alsalamah, Asma Alatawi, Sara Alfaraj · 6 authors
Delivering electronic health care (eHealth) services across multi-cloud providers to implement patient-centric care demands a trustworthy brokering architecture. Specifically, such an architecture should aggregate relevant medical information to allow informed decision-making. It should also ensure that this information is complete and authentic and that no one has tampered with it. Brokers deployed in eHealth services may fall short of meeting such criteria due to two key behaviors. The first involves violating international health-data protection laws by allowing user anonymity and limiting user access rights. Second, brokers claiming to provide trustworthy transactions between interested parties usually rely on user feedback, an approach vulnerable to manipulation by malicious users. This paper addresses these data security and trust challenges by proposing HealthyBroker, a novel, trust-building brokering architecture for multiple cloud environments. This architecture is designed specifically for patient-centric cloud eHealth services. It enables care-team members to complete eHealth transactions securely and access relevant patient data on a “need-to-know” basis in compliance with data-protection laws. HealthyBroker also protects against potential malicious behavior by assessing the trust relationship and tracking it using a neutral, tamper-proof, distributed blockchain ledger. Trust is assessed based on two strategies. First, all transactions and user feedback are tracked and audited in a distributed ledger for transparency. Second, only feedback coming from trustworthy parties is taken into consideration. HealthyBroker was tested in a simulated eHealth multi-cloud environment. The test produced better results than a benchmark algorithm in terms of data accuracy, service time, and the reliability of feedback received as measured by three malicious behavior models (naïve, feedback isolated, and feedback collective). These results demonstrate that HealthyBroker can provide care teams with a trustworthy, transparent ecosystem that can facilitate information sharing and well-informed decisions for patient-centric care.
İbrahim Korkmaz Kahraman, Habib Küçükşahin, Emin ÇAĞLAK
Forecasting models based on the assumption that returns are normally distributed do not perform sufficiently on shallow markets. These models are more likely to fail in the estimation of the extreme points that can be reached especially at high volatility markets, and this situation is led to investors in predicting volatility. In the volatility forecasting of crypto money, which is seen as an alternative investment tool for the financial investors, single volatility models such as, ARCH, GARCH, T-GARCH, GARCH-M, E-GARCH, and I-GARCH and long memory models (AP-GARCH and C-GARCH) was utilized. In addition, the most suitable model was tried to be tested among the models used for volatility estimation. In this context, the price data of Bitcoin, Ethereum and Ripple cryptocurrency with the highest market value in the crypto money market have been utilized between 24/08/2016-07/05/2018. According to the results of the research, for Bitcoin and Ethereum, the volatility effect of the shocks is permanent and the effect of the positive shocks is more than that of the negative shocks, whereas for Ripple, the volatility effect of the shocks is transient and the passivity of the volatility is short.
Boyu Wang, Morteza Dabbaghjamanesh, Abdollah Kavousi‐Fard, Shahab Mehraeen
Power grid resilience, reliability, and sustainability can be improved significantly by decomposing the large grids into networked microgrids (NMGs). However, the optimal energy management problem and preserving the security in NMGs are more complicated and challenging. This paper aims to propose a secured stochastic energy management framework for NMGs based on the modified blockchain approach, utilizing the directed acyclic graph (DAG). Using the decentralized and transparent blockchain technology will help to have higher security and lower risks within the network, thus eliminating the financial fraud and cutting down the total operational cost. In order to address the issues arising in the traditional blockchain models, mainly due to the storage and high complexities of hash address calculations, this paper proposes a new modified blockchain technology based on the DAG method. Also, a novel data restoration technique is developed to provide a way to restore the data with appropriate accuracy. The unscented transform (UT) approach is employed to model the uncertainties of forecast error in hourly load demand, solar power output, and wind turbines power output. Finally, the proposed model is tested on an NMG system with four MGs, including two residential MGs (as the noncrucial loads), a commercial MG (as the intermediate level loads), and a hospital MG (as the crucial loads).
Muhammad Owais Qarni, Saqib Gulzar, Syeda Tamkeen Fatima, Majid Jamal Khan · 5 authors
This paper investigates the volatility spillover dynamics between U.S. Bitcoin and financial markets from July 19, 2010 to December 29, 2017. Diebold and Yilmaz (2012) volatility spillover index, Barunik, Kocenda, and Vacha (2017) Spillover Asymmetry Measure, and Barunik and Krehlik (2018) frequency connectedness methodologies are applied to investigate the time varying dynamics of volatility spillover among U.S. Bitcoin and financial markets. The findings of the study indicate the presence of low level of integration and contagion between U.S. Bitcoin and financial markets. Asymmetric nature of volatility spillover is also detected. The connectedness among the U.S. Bitcoin and financial markets is found to be concentrated at high frequency, suggesting that markets process information rapidly. Moreover, the turbulence in Bitcoin market will have insignificant effect on U.S. financial markets. This non-contagion nature of Bitcoin markets provides significant risk hedging and diversification benefits for domestic and foreign investors in the U.S.