The Vulnerability of the Blockchain Network From the Consensus Perspective

2022 ◽  
pp. 1-20
Author(s):  
Mohamed Ikbal Nacer ◽  
Simant Prakoonwit

The blockchain is a registry shared among different participants intending to eliminate the need for a central authority to maintain information. The first proposal of this technology was to eliminate financial authorities in transactions of value. However, the application of the same technique for the transaction of information could facilitate trades and offer traceability and diamond tracking around the world. The consensus is at the core of the network because it orchestrates nodes to accept new information, but it operates over a data structure in an open network, consequently leading to many complex behaviours that introduce different vulnerabilities. This work aims to highlight the vulnerability within the blockchain network based on the different participant behaviours that dominate the shared registry. Moreover, different malicious behaviour can appear on the networking layer by taking advantage of the network topology.

Author(s):  
Ricardo Giglio ◽  
Thomas Lux

AbstractWe investigate the network topology of a comprehensive data set of the world-wide population of corporate entities. In particular, we have extracted information on the boards of all companies listed in Bloomberg’s archive of company profiles in October, 2015, a total of almost 100,000 firms. We provide information on board membership overlaps at various levels, and, in particular, show that there exists a core of directors who accumulate a large number of seats and are highly connected among themselves both at the level of national networks and at the worldwide aggregated level.


Author(s):  
Oxana Karnaukhova

Transnational communication is a natural effect escorting activities of research teams throughout the world. We understand this phenomenon not as a new-born process mediated by technologies, but the process of cross-border dissemination of opinions, information, ideas, and toolkits. We also recognize that while so-called “new” information and communications technologies (ICTs) have created their own specific problems and concerns, it should be remembered that all forms of communication are capable of causing tensions and latent conflicts (Cupach, 1997; Ribeiro, 1998). The study concerns networking and ICT-mediated collaboration in transnational research teams with Russian participation affected by cultural differences. The core interest lies in investigation of communicative strategies and effects of visual and interactive techniques, including video-conferencing, participatory social media, podcasting, and others--and, to collaboratively construct, interpret, and theorize participants’ accounts of cooperation.


2020 ◽  
Vol 2 (1) ◽  
pp. 23-37
Author(s):  
Syarifudin Syarifudin

Each religious sect has its own characteristics, whether fundamental, radical, or religious. One of them is Insan Al-Kamil Congregation, which is in Cijati, South Cikareo Village, Wado District, Sumedang Regency. This congregation is Sufism with the concept of self-purification as the subject of its teachings. So, the purpose of this study is to reveal how the origin of Insan Al-Kamil Congregation, the concept of its purification, and the procedures of achieving its purification. This research uses a descriptive qualitative method with a normative theological approach as the blade of analysis. In addition, the data generated is the result of observation, interviews, and document studies. From the collected data, Jamaah Insan Al-Kamil adheres to the core teachings of Islam and is the tenth regeneration of Islam Teachings, which refers to the Prophet Muhammad SAW. According to this congregation, self-perfection becomes an obligation that must be achieved by human beings in order to remember Allah when life is done. The process of self-purification is done when human beings still live in the world by knowing His God. Therefore, the peak of self-purification is called Insan Kamil. 


Edupedia ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 45-53
Author(s):  
Ilzam Dhaifi

The world has been surprised by the emergence of a COVID 19 pandemic, was born in China, and widespread to various countries in the world. In Indonesia, the government issued several policies to break the COVID 19 pandemic chain, which also triggered some pro-cons in the midst of society. One of the policies government takes is the closure of learning access directly at school and moving the learning process from physical class to a virtual classroom or known as online learning. In the economic sector also affects the parents’ financial ability to provide sufficient funds to support the implementation of distance learning applied by the government. The implications of the distance education policy are of course the quality of learning, including the subjects of Islamic religious education, which is essentially aimed at planting knowledge, skills, and religious consciousness to form the character of the students. Online education must certainly be precise, in order to provide equal education services to all students, prepare teachers to master the technology, and seek the core learning of Islamic religious education can still be done well.


Author(s):  
Roy Livermore

Despite the dumbing-down of education in recent years, it would be unusual to find a ten-year-old who could not name the major continents on a map of the world. Yet how many adults have the faintest idea of the structures that exist within the Earth? Understandably, knowledge is limited by the fact that the Earth’s interior is less accessible than the surface of Pluto, mapped in 2016 by the NASA New Horizons spacecraft. Indeed, Pluto, 7.5 billion kilometres from Earth, was discovered six years earlier than the similar-sized inner core of our planet. Fortunately, modern seismic techniques enable us to image the mantle right down to the core, while laboratory experiments simulating the pressures and temperatures at great depth, combined with computer modelling of mantle convection, help identify its mineral and chemical composition. The results are providing the most rapid advances in our understanding of how this planet works since the great revolution of the 1960s.


Author(s):  
Michael Thompson ◽  
M. Bruce Beck ◽  
Dipak Gyawali

Food chains interact with the vast, complex, and tangled webs of material flows —nitrogen, phosphorus, carbon, water, energy—circling the globe. Cities and households are where those material flows interact with the greatest intensity. At every point within these webs and chains, technologies enable them to function: from bullock-drawn ploughs, to mobile phones, to container ships, to wastewater treatment plants. Drawing on the theory of plural rationality, we show how the production and consumption of food and water in households and societies can be understood as occurring according to four institutionally induced styles: four basic ways of understanding the world and acting within it; four ways of living with one another and with nature. That there are four is due to the theory of plural rationality at the core of this chapter.


2020 ◽  
Vol 100 (1) ◽  
pp. 40-55 ◽  
Author(s):  
Robert L. Conner ◽  
Greg J. Boland ◽  
Chris L. Gillard ◽  
Yongyan Chen ◽  
Xuechan Shan ◽  
...  

Anthracnose, caused by the fungus Colletotrichum lindemuthianum (Sacc. & Magnus) Briosi & Cavara, is one of the most destructive diseases of dry bean (Phaseolus vulgaris L.) in the world. Between 2005 and 2015, commercial fields of dry beans in Manitoba and Ontario were surveyed to determine the frequency of occurrence of races of the anthracnose fungus. Throughout the study, race 73 was most prevalent in Manitoba and Ontario. However, three anthracnose races not previously reported in Canada also were identified. These three new races and four previously identified anthracnose races were used to screen 52 dry bean cultivars, as well as a mung bean and azuki bean cultivar from Ontario, for their seedling reactions to determine their patterns of race resistance. The dry bean cultivars were classified into a total of 19 resistance spectra based on the pattern of seedling reactions to the seven anthracnose races. The most common resistance spectrum was susceptible to the majority of the anthracnose races and no cultivar was resistant to all of the races. Many bean cultivars produced intermediate anthracnose ratings to races 31 and 105 and tests of 16 dry bean cultivars against those races indicated that all cultivars with intermediate ratings to a specific race were segregating in their seedling reactions and none of the cultivars produced plants with only intermediate anthracnose severity ratings. This study provides new information on the anthracnose reactions of common bean cultivars in Canada, which should be useful for the development of new bean cultivars with durable resistance.


Author(s):  
Paul Marty ◽  
Jacopo Romoli

AbstractMaximize Presupposition! (MP), as originally proposed in Heim (Semantik: Ein internationales Handbuch der zeitgenössischen Forschung, pp. 487–535, 1991) and developed in subsequent works, offers an account of the otherwise mysterious unassertability of a variety of sentences. At the core of MP is the idea that speakers are urged to use a sentence ψ over a sentence ϕ if ψ contributes the same new information as ϕ, yet carries a stronger presupposition. While MP has been refined in many ways throughout the years, most (if not all) of its formulations have retained this characterisation of the MP-competition. Recently, however, the empirical adequacy of this characterisation has been questioned in light of certain newly discovered cases that are infelicitous, despite meeting MP-competition conditions. This has led some researchers to broaden the scope of MP, extending it to competition between sentences which are not contextually equivalent (Spector and Sudo in Linguistics and Philosophy 40(5):473–517, 2017) and whose presuppositions are not satisfied in the context (Anvari in Proceedings of Semantics and Linguistic Theory 28, pp. 711–726, 2018; Manuscript, IJN-ENS, 2019). In this paper, we present a body of evidence showing that these formulations of MP are sometimes too liberal, sometimes too restrictive: they overgenerate infelicity for a variety of felicitous cases while leaving the infelicity of minimally different cases unaccounted for. We propose an alternative, implicature-based approach stemming from Magri (PhD dissertation, MIT, 2009), Meyer (PhD dissertation, MIT, 2013), and Marty (PhD dissertation, MIT, 2017), which reintroduces contextual equivalence and presupposition satisfaction in some form through the notion of relevance. This approach is shown to account for the classical and most of the novel cases. Yet some of the latter remain problematic for this approach as well. We end the paper with a systematic comparison of the different approaches to MP and MP-like phenomena, covering both the classical and the novel cases. All in all, the issue of how to properly restrict the competition for MP-like phenomena remains an important challenge for all accounts in the literature.


2015 ◽  
Vol 7 (1) ◽  
pp. 80-97
Author(s):  
Siaw-Fong Chung

The analysis in this paper was based on five Malay narratives of the “frog story”. In these narratives, the types of lexical arguments and their relations with information flow and topic continuity were analyzed. It was found that most narrators used one lexical argument in telling the frog story (e.g., sarang itu jatuh “the nest fell”). About 60% of the verbs in the narratives contained one lexical argument only. Some transitive verbs that usually require the presence of both lexical arguments were used with one lexical argument only when produced in speech (e.g., dia mencari ø di merata tempat “he searched (for) ø everywhere”). Objects were sometimes omitted, as their meanings could be predicted from previous context. Despite the omission of objects, transitive constructions still prevailed in the stories. The most frequently occurring lexical arguments were objects (O) (37%), followed by intransitive subjects (S) (29%) and transitive subjects (A) (27%). In addition, our results showed that new information in Malay was usually allocated to the core argument of the object and to locative expressions, indicating that most of the new information appeared at the end of a clause. On the other hand, topic continuity was held between the subjects in two continuous intonation units. This clear-cut division of discourse functions in the heads and tails of constructions was consistently found in the five pieces of narration. This observation not only showed how ideas could be continued in Malay oral narratives, but also contributes to the study of discourse structure in Malay.


Author(s):  
Ned Augenblick ◽  
Matthew Rabin

Abstract When a Bayesian learns new information and changes her beliefs, she must on average become concomitantly more certain about the state of the world. Consequently, it is rare for a Bayesian to frequently shift beliefs substantially while remaining relatively uncertain, or, conversely, become very confident with relatively little belief movement. We formalize this intuition by developing specific measures of movement and uncertainty reduction given a Bayesian’s changing beliefs over time, showing that these measures are equal in expectation and creating consequent statistical tests for Bayesianess. We then show connections between these two core concepts and four common psychological biases, suggesting that the test might be particularly good at detecting these biases. We provide support for this conclusion by simulating the performance of our test and other martingale tests. Finally, we apply our test to data sets of individual, algorithmic, and market beliefs.


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