Saeed Nosratabadi, Amir Mosavi, Puhong Duan, Pedram Ghamisi
This paper provides the state of the art of data science in economics. Through a novel taxonomy of applications and methods advances in data science are investigated. The data science advances are investigated in three individual classes of deep learning models, ensemble models, and hybrid models. Application domains include stock market, marketing, E-commerce, corporate banking, and cryptocurrency. Prisma method, a systematic literature review methodology is used to ensure the quality of the survey. The findings revealed that the trends are on advancement of hybrid models as more than 51% of the reviewed articles applied hybrid model. On the other hand, it is found that based on the RMSE accuracy metric, hybrid models had higher prediction accuracy than other algorithms. While it is expected the trends go toward the advancements of deep learning models.
Abstract Blockchain networks have attracted tremendous attention for creating cryptocurrencies and decentralized economies built on peer-to-peer protocols. However, the complex nature of the dynamics and feedback mechanisms within these economic networks has rendered it difficult to reason about the growth and evolution of these networks. Hence, proper mathematical frameworks to model and analyze the behavior of blockchain-enabled networks are essential. To address this need, we establish a formal mathematical framework, based on dynamical systems, to model the core concepts in blockchain-enabled economies. Drawing on concepts from differential games, control engineering, and stochastic dynamical systems, this paper proposes a methodology to model, simulate, and engineer networked token economies. To illustrate our framework, a model of a generalized token economy is developed, where miners provide a commodity service to a platform in exchange for a cryptocurrency and users consume a service from the platform. We illustrate the dynamics of token economies by simulating and testing two different block reward strategies. We then conclude by outlining future research directions that will integrate additional methods from signal processing and control theory into the toolkit for designers of blockchain-enabled economic systems.
Oscar Delgado-Mohatar, Julián Fiérrez, Rubén Tolosana, Rubén Vera-Rodríguez
Blockchain technologies provide excellent architectures and practical tools for securing and managing the sensitive and private data stored in biometric templates, but at a cost. We discuss opportunities and challenges in the integration of blockchain and biometrics, with emphasis in biometric template storage and protection, a key problem in biometrics still largely unsolved. Key tradeoffs involved in that integration, namely, latency, processing time, economic cost, and biometric performance are experimentally studied through the implementation of a smart contract on the Ethereum blockchain platform, which is publicly available in github for research purposes.
Blockchain implications within the sustainability domain are rapidly arousing the interest of researchers and institutions. However, despite the avalanche of articles, papers, and recently published books, innovation in the blockchain domain is still heavily influenced by light literature, such as news, articles, opinion posts, and white papers. Lacking a homogeneous literature background, case studies often fall into storytelling, providing mere descriptions of the facts according to the writers’ impressions and opinions. We therefore investigate blockchain adoption for sustainable purposes through a case study while remaining firmly grounded in three main theoretical literature streams: knowledge management, knowledge infrastructure, and trust. Since blockchain interaction with the real world is managed by oracles, addressing the oracle problem is essential in order to evaluate the effectiveness of blockchain for sustainability issues. However, to the best of the authors’ knowledge, no other paper has efficiently addressed this subject or even mentioned it. Recognizing its scarce consideration in the literature, the oracle problem will be analyzed in both theoretical and practical terms, thereby providing a way to solve the issues related to non-fungible products in the supply chain. Choice over the selected case study was made in light of the divergence in motives for the adoption of blockchain (economic over social), which makes the results more inferable at a broader scale and offers an insight into how sustainable innovations can also be economically viable.
The limitation with smart contracts is that they cannot access external data which might be required to control the execution of business logic. Oracles can be used to provide external data to smart contracts. An oracle is an interface that delivers data from external data outside the blockchain to a smart contract to consume. Oracle can deliver different types of data depending on the industry and requirements. In this paper, we study and describe the widely used blockchain oracles. Then, we elaborate on his potential role, technical architecture, and design patterns. Finally, we discuss the human oracle and his key role in solving the truth problem by reaching a consensus about a certain inquiry and tasks.
In recent years, many researchers have focused on developing a feasible solution for storing and exchanging medical images in the field of health care. Current practices are deployed on cloud-based centralized data centers, which increase maintenance costs, require massive storage space, and raise privacy concerns about sharing information over a network. Therefore, it is important to design a framework to enable sharing and storing of big medical data efficiently within a trustless environment. In the present paper, we propose a novel proof-of-concept design for a distributed patient-centric image management (PCIM) system that is aimed to ensure safety and control of patient private data without using a centralized infrastructure. In this system, we employed an emerging Ethereum blockchain and a distributed file system technology called Inter-Planetary File System (IPFS). Then, we implemented an Ethereum smart contract called the patient-centric access control protocol to enable a distributed and trustworthy access control policy. IPFS provides the means for decentralized storage of medical images with global accessibility. We describe how the PCIM system architecture facilitates the distributed and secured patient-centric data access across multiple entities such as hospitals, patients, and image requestors. Finally, we deployed a smart contract prototype on an Ethereum testnet blockchain and evaluated the proposed framework within the Windows environment. The evaluation results demonstrated that the proposed scheme is efficient and feasible.
The objective of this study is to analyse the phenomenon of flypaper effect in Aceh after the implementation of fiscal decentralization. Data used in the study were panel data covering all 23 district/municipalities in Aceh from 2011 to 2013. Pooled Least Square was utilized. The results of this study revealed that ownsource revenue, sharing revenue, special allocation funds, general allocation funds, and special autonomy funds are statistically significant variables and have a positive relation to regional spending. It was proven that flypaper effect has occured in Aceh as the coefficient of the own-source revenue variabel was smaller than that of sharing revenue variabel. This implied that Aceh has been dependent on the national government in term of regional financing. Based on descriptive analysis, provinces having dominant share of tertiary sector to their regional gross domestic products show fiscally independent. In order to achieve fiscal independence, the phenomenon of flypaper effect could be overcomed by shifting the economic structure from the primary and secondary to the tertiary sectors of the economy. In doing so, the contribution of own-source revenue to regional spending outweigh intergovernment transfer funds from national government.
Kejiao Li, Hui Li, Han Wang, Huiyao An · 7 authors
The blockchain has a great vogue in recent years, and its core consensus algorithms also become the focus of research. At present, most of the research on consensus mechanisms are oriented to the public blockchain and based on existing consensus mechanisms or sophisticated distributed algorithms. Various application scenarios have been developed based on the consortium blockchain, while few researchers pay attention to customize consistency algorithms. Moreover, there is a trade-off between security and performance in designing consensus mechanisms. We propose a novel consensus algorithm called Proof of Vote (PoV), where the distributed nodes controlled by consortium members could reach consensus and come to a decentralized arbitration by voting. PoV separates the voting rights and bookkeeping rights with the essential idea of establishing different security identities for network nodes. Contrary to the third-party intermediary or uncontrollable public awareness, the production and verification of PoV blocks are decided by the voting results among the core consortium members. We theoretically prove that PoV blocks can reach transaction finality by only one confirmation. Compared with the total traffic complexity of BFT-based consensus, PoV has just that of O( ), which is a great improvement when the number of nodes is over 100.
Multiculturalism as the coexistence in the same society of persons from different cultures poses a challenge to our contemporary societies. The role of education is basic to face the opportunities and potential problems of multiculturalism. In Spain educational system is decentralized, therefore, the different autonomous regions can establish laws related to education within their territories. The model of multicultural education in Castilla La Mancha is directly related to social cohesion and has a commitment to inclusive education. This implies the transformation of teaching practices, as well as changes in the schools' culture and organization. Intercultural education pursues equity, intercultural competence, social transformation and the fight against discrimination. An inclusive school is characterized by a high commitment of teachers and a positive attitude towards heterogeneous groups, because they are the reflection of our society. This will result into an effort to offer human, material or technical, support in the ordinary classroom. / Keywords: multiculturalism, social change, education, educational inclusion
This paper studies simple moving average trading strategies employing daily price data on the ten most-traded cryptocurrencies that exhibit the ‘privacy function’. Investigating the 2016–2018 period, our results indicate a variable moving average strategy is successful only when applied to Dash generating returns of 14.6%−18.25% p.a. in excess of the simple buy-and-hold benchmark strategy. However, when applying our technical trading rules to the entire set of ten privacy coins shows that, on an aggregate level, simple technical trading rules do not generate positive returns in excess of a buy-and-hold strategy.
Purpose The authors develop new quantitative methods to estimate the level of speculation and long-term sustainability of Bitcoin and Blockchain. Design/methodology/approach The authors explore the practical application of speculative bubble models to cryptocurrencies. They then show how the approach can be extended to provide estimated brand values using data from Google Trends. Findings The authors confirm previous findings of speculative bubbles in cryptocurrency markets. Relatedly, Google searches for cryptocurrencies seem to be primarily driven by recent price rises. Overall results are sufficient to question the long-term sustainability of Bitcoin with the suggestion that Ethereum, Bitcoin Cash and Ripple may all enjoy technical advantages relative to Bitcoin. Our results also demonstrate that Blockchain has a distinct value and identity beyond cryptocurrencies – providing foundational support for the second generation of academic work on Blockchain. However, a relatively low estimated long-term growth rate suggests that the benefits of Blockchain may take a long time to be fully realised. Originality/value The authors contribute to an emerging academic literature on Blockchain and to a more established literature exploring the use of Google data within business analytics. Their original contribution is to quantify the business value of Blockchain and related technologies using Google Trends
Cryptocurrency telah menjadi fenomena global saat ini. Berdasarkan hasil Survei GlobalWebIndex menyebutkan bahwa ada sekitar 10% pengguna internet di Indonesia telah memiliki mata uang digital. Persentase tersebut menjadikan Indonesia peringkat 5 pengguna cryptocurrency terbanyak di dunia. Tujuan penelitian ini adalah untuk melihat risiko dan tingkat keuntungan investasi cryptocurrency. Metodologi yang digunakan dalam artikel ini adalah metode kualitatif deskriptif dengan pendekatan normatif. Data yang digunakan penulis adalah data sekunder yang bersifat publik seperti abstrak, hasil publikasi ilmiah, buku, media dan jejaring sosial yang membahas tentang cryptocurrency. Hasil dari pembahasan artikel ini dapat menunjukkan bahwa jenis investasi cryptocurrency memiliki return / tingkat keuntungan yang signifikan, karena cryptocurrency sudah masuk kedalam bursa efek, kebijakan teknologi, memiliki jumlah pasokan yang terbatas, anti-inflasi, keamanannya dilindungi oleh kriptografi dan biaya transaksinya lebih rendah . Namun demikian, investasi cryptocurrency juga memiliki risiko yang cukup tinggi. Risiko dan return dari suatu investasi memiliki hubungan yang linier. Berdasarkan hasil dari pembahasan dapat disangkal juga bahwa investasi pada cryptocurrency memiliki risiko yang cukup tinggi, karena memiliki volatilitas yang ekstrem, perubahan nilai cryptocurrency hanya merupakan bubble / antusiasme yang sewaktu-waktu, minimnya regulasi, masih menyisakan isu-isu legalitas, menjadi incaran kejahatan siber dan memiliki ketergantungan tehadap teknologi. Kata Kunci : Risiko, Tingkat Keuntungan, Investasi, Cryptocurrency
Lanfranco Zanzi, Antonio Albanese, Vincenzo Sciancalepore, Xavier Costa‐Pérez
With the advent of revolutionary technologies, such as virtualization and softwarization, a novel concept for 5G networks and beyond has been unveiled: Network Slicing. Initially driven by the research community, standardization bodies as 3GPP have embraced it as a promising solution to revolutionize the traditional mobile telecommunication market by enabling new business models opportunities. Network Slicing is envisioned to open up the telecom market to new players such as Industry Verticals, e.g., automotive, smart factories, e-health, etc. Given the large number of potential new business players, dubbed as network tenants, novel solutions are required to accommodate their needs in a cost-efficient and secure manner. In this paper, we propose NSBchain, a novel network slicing brokering (NSB) solution, which leverages on the widely adopted Blockchain technology to address the new business models needs beyond traditional network sharing agreements. NSBchain defines a new entity, the Intermediate Broker (IB), which enables Infrastructure Providers (InPs) to allocate network resources to IBs through smart contracts and IBs to assign and re-distribute their resources among tenants in a secure, automated and scalable manner. We conducted an extensive performance evaluation by means of an open-source blockchain platform that proves the feasibility of our proposed framework considering a large number of tenants and two different consensus algorithms.
Yaşam koşulları, ihtiyaçların değişimi, teknolojik gelişmeler ve finansal krizler paranın gelişiminde önemli rol oynamıştır. Literatürde, özellikle 2008 yılında yaşanan finansal kriz sonrasında Bitcoin kripto parasının doğduğu ifade edilmektedir. Satoshi Nakamoto tarafından geliştirilen eşler arası nakit sistemi, Bitcoin ile birlikte, kripto varlık, blokzincir ve dağıtılmış defter teknolojisi kavramlarının da gündeme gelmesine neden olmuştur. Günümüzde çok sayıda kripto varlığın mevcut olduğu, kripto varlıkların sayısında, türünde ve işlem hacimlerinde artış olduğu gözlenmektedir. Bu genişleme beraberinde Bitcoin ve diğer kripto varlıkların muhasebeleştirilmesi konusunu da gündeme getirmiştir. Bu çalışmada kripto varlıklar, kripto varlıkların çeşitleri, temini ve mevcut durumu hakkında bilgi verilmeye, IASB tarafından kamuoyunun görüşüne sunulan kripto paraların muhasebeleştirilmesine ilişkin geçici gündem kararı incelenmeye, kripto para dışındaki diğer kripto varlıkların muhasebeleştirilmesi incelenmeye çalışılmıştır. IASB kripto paraların satılmak için elde tutulması durumunda IAS 2 Stoklar Standardı kapsamında, diğer hallerde IAS 38 Maddi Olmayan Duran Varlık Standardı kapsamında değerlendireceğine dair geçici karar bildirmiştir. Diğer taraftan, kripto para dışındaki kripto varlıkların muhasebeleştirilmesi için gerekli düzenlemelerin yapılması da önerilebilir.
Security of payment (SOP) issues still persist in the construction industry despite numerous investigations and incremental reforms. Various solutions and policies have been proposed and analysed in-depth in previous studies. However, limited studies have focused on the integration of advanced technologies to address SOP issues. The aim of this research is to develop a comprehensive framework that integrates practical advanced technologies to address SOP issues in the construction industry. A concurrent mixed-method design was adopted to (a) identify the industry's perspective on what advanced technologies can be accepted to address SOP issues through a questionnaire survey, and (b) identify the use of advanced technologies through a live construction project as a case study. Subsequently, a data flow diagram framework was developed to articulate the whole process flow of how the system delivers automatic payments to subcontractors upon the completion of their contractual obligations and work done. This research contributes new and practical insights into the application and integration of smart sensors, oracles, BIM, blockchain technology and smart contracts in addressing SOP issues in the construction industry.
Blockchain technology has become a paradigm shift to digital transactions. It has brought massive potentials in many fields, such as financial services, energy, healthcare and Internet of Things. As often occurs with innovative technologies, it has suffered from several critical Cybersecurity threats and vulnerabilities.
Younghun Lee, Shailendra Rathore, Jin Ho Park, Jong Hyuk Park · 6 authors
Abstract With the advancement of Information and Communication Technology (ICT) and the proliferation of sensor technologies, the Internet of Things (IoT) is now being widely used in smart home for the purposes of efficient resource management and pervasive sensing. In smart homes, various IoT devices are connected to each other, and these connections are centered on gateways. The role of gateways in the smart homes is significant, however, its centralized structure presents multiple security vulnerabilities such as integrity, certification, and availability. To address these security vulnerabilities, in this paper, we propose a blockchain-based smart home gateway network that counters possible attacks on the gateway of smart homes. The network consists of three layers including device, gateway, and cloud layers. The blockchain technology is employed at the gateway layer wherein data is stored and exchanged in the form blocks of blockchain to support decentralization and overcome the problem from traditional centralized architecture. The blockchain ensures the integrity of the data inside and outside of the smart home and provides availability through authentication and efficient communication between network members. We implemented the proposed network on the Ethereum blockchain technology and evaluated in terms of standard security measures including security response time and accuracy. The evaluation results demonstrate that the proposed security solutions outperforms over the existing solutions.
Security-related data collection is an essential part for attack detection and security measurement in Mobile Ad Hoc Networks (MANETs). Due to no fixed infrastructure of MANETs, a detection node playing as a collector should discover available routes to a collection node for data collection. Notably, route discovery suffers from many attacks (e.g., wormhole attack), thus the detection node should also collect securityrelated data during route discovery and analyze these data for determining reliable routes. However, few literatures provide incentives for security-related data collection in MANETs, and thus the detection node might not collect sufficient data, which greatly impacts the accuracy of attack detection and security measurement. In this paper, we propose B4SDC, a blockchain system for security-related data collection in MANETs. Through controlling the scale of RREQ forwarding in route discovery, the collector can constrain its payment and simultaneously make each forwarder of control information (namely RREQs and RREPs) obtain rewards as much as possible to ensure fairness. At the same time, B4SDC avoids collusion attacks with cooperative receipt reporting, and spoofing attacks by adopting a secure digital signature. Based on a novel Proof-of-Stake consensus mechanism by accumulating stakes through message forwarding, B4SDC not only provides incentives for all participating nodes, but also avoids forking and ensures high efficiency and real decentralization at the same time. We analyze B4SDC in terms of incentives and security, and evaluate its performance through simulations. The thorough analysis and experimental results show the efficacy and effectiveness of B4SDC.
Although blockchain-based smart contracts promise a ``trustless'' way of enforcing agreements even with monetary consequences, they suffer from multiple security issues. Many of these issues could be mitigated via an effective access control system, however, its realization is challenging due to the properties of current blockchain platforms (like lack of privacy, costly on-chain resources, or latency). To address this problem, we propose the SMACS framework, where updatable and sophisticated Access Control Rules (ACRs)} for smart contracts can be realized with low cost. SMACS shifts the burden of expensive ACRs validation and management operations to an off-chain infrastructure, while implementing on-chain only lightweight token-based access control. SMACS is flexible and in addition to simple access control lists can easily implement rules enhancing the runtime security of smart contracts. With dedicated ACRs backed by vulnerability-detection tools, SMACS can protect vulnerable contracts after deployment. We fully implement SMACS and evaluate it.
Cryptocurrencies in recent years, have emerged as an innovative means of carrying out online financial transactions, but concerns have been raised among experts about their impact on our environmental. Cryptocurrencies place enormous demand on the energy system, and this increases carbon emissions which sequentially adds up to the overall effects of global warming. However, the technology that powers bitcoin (blockchain) should be considered for future adoption. The environmental hazard regarding cryptocurrency usage stems from the large carbon footprint left by such small share of global cashless transactions, and its potential to be broadly integrated into current technologies. This study examines the impact of cryptocurrency on the environment with its focus on climate change (Global warming). Although the fate of bitcoin is currently unpredictable, it can be projected that if its rate of adoption is accelerated, its electricity demand is capable of producing sufficient emissions to surpass 2C of global warming in a few decades. The study recommends that further development in cryptocurrencies should analytically aim to reduce power demand so as to avoid the potentially demoralizing consequences of 2 O C of global warming.
Vyper has been proposed as a new high-level language for Ethereum smart contract development due to numerous security vulnerabilities and attacks witnessed on contracts written in Solidity since the system's inception. Vyper aims to address these vulnerabilities by providing a language that focuses on simplicity, auditability and security. We present a survey where we study how well-known and commonly-encountered vulnerabilities in Solidity feature in Vyper's development environment. We analyze all such vulnerabilities individually and classify them into five groups based on their status in Vyper. To the best of our knowledge, our survey is the first attempt to study security vulnerabilities in Vyper.