БЛОКЧЕЙН бИТКОИН: Типология участников

The paper describes the classification and criteria for blockchain environment participants. The overview of the main types of blockchain participants is essential for the understanding of blockchain social and economic behaviour. It structured in the description of the several patterns which is often generated inside the Bitcoin blockchain and the list of the economic entities with the criteria of their behaviour. The paper gives the view on the different types of blockchain entities both from outside and inside the blockchain. Also, the paper lists the possible risks of criminal behaviour corresponding to every entity.El artículo describe la clasificación y los criterios para los participantes del entorno de blockchain. La descripción general de los principales tipos de participantes de blockchain es esencial para la comprensión del comportamiento social y económico de blockchain. Se estructura en la descripción de los diversos patrones que a menudo se generan dentro de la cadena de bloques de Bitcoin y la lista de las entidades económicas con los criterios de su comportamiento. El documento ofrece una vista de los diferentes tipos de entidades de blockchain tanto desde fuera como desde dentro de blockchain. Además, el documento enumera los posibles riesgos de comportamiento criminal que corresponden a cada entidad.В статье описывается классификация и критерии классификации участников блокчейн среды. Обзор основных видов блокчейн участников имеет важное значение для понимания социального и экономического поведения в блокчейн. Статья структурирована как описание нескольких моделей, которые часто возникают внутри блокчейн Биткоин и перечень хозяйствующих субъектов с критериями их поведения. В статье дается представление о различных типах блокчейн структур со взглядом как снаружи, так и внутри блокчейн. Кроме того, в документе перечислены возможные риски преступного поведения, соответствующего каждому объект

Accuracy assessment and cross-validation of LPWAN propagation models in urban scenarios

Abstract With the proliferation of machine-to-machine (M2M) communication in the course of the last decade, the importance of low-power wide-area network (LPWAN) technologies intensifies. However, the abundance of accurate propagation models proposed for these systems by standardization bodies, vendors, and research community hampers the deployment planning. In this paper, we question the selection of accurate propagation models for Narrowband IoT (NB-IoT), LoRaWAN, and Sigfox LPWAN technologies, based on extensive measurement campaign in two mid-size European cities. Our results demonstrate that none of the state-of-the-art models can accurately describe the propagation of LPWAN radio signals in an urban environment. For this reason, we propose enhancements to the selected models based on our experimental measurements. Performing the fine-tuning of the propagation models for one of the cities, we select Ericsson Urban (NB-IoT, LoRaWAN) and 3GPP (Sigfox) models as the ones providing the closest match. Finally, we proceed to perform cross-validation of the propagation models using the data set for another city. The tuned models demonstrate an excellent match with the real data in the cross-validation phase. They outperform their competitors by at least 20–80% in terms of relative deviation from the measured signal levels presenting the accurate option for NB-IoT, LoRaWAN, and Sigfox deployments planning in mid-size cities

LPWAN coverage assessment planning without explicit knowledge of base station locations

Abstract An assessment of radio network coverage, usually in the form of a measurement campaign, is essential for multi-base-station (multi-BS) network deployment and maintenance. It can be conducted by a network operator or its served consumers. However, the number of measurement points and their locations may not be known in advance for an efficient and accurate evaluation. The main goal of this study is to propose a new methodology for understanding the selection of measurement points during coverage and signal quality assessment. It is particularly tailored to multi-BS low-power wide-area network (LPWAN) deployments without explicit knowledge of BS locations. To this aim, we first conduct a large-scale measurement campaign for three popular LPWAN technologies, namely, NB-IoT, Sigfox, and LoRaWAN. Utilizing this baseline data, we develop a procedure for identifying the minimum set of measurement points for the coverage assessment with a given accuracy as well as study which interpolation algorithms produce the lowest approximation error. Our results demonstrate that a random choice of measurement points is on par with their deterministic selection. Out of the candidate interpolation algorithms, Kriging method offers attractive performance in terms of the absolute error for NB-IoT deployments. By contrast, for Sigfox and LoRaWAN infrastructures, less complex techniques, such as Natural-neighbor, Linear interpolation, or Inverse-Distance Weighting, can achieve comparable (and occasionally even better) accuracy levels

Probing electrochemical reactivity in an Sb2S3-containing potassium-ion battery anode: Observation of an increased capacity

Potassium-ion batteries are attracting considerable attention as a viable type of high voltage battery. Among available anode materials, composites containing Sb2S3are some of the most interesting high capacity candidates. A nanostructured Sb2S3-reduced graphene oxide composite anode material is evaluated in this study and compared with a structurally similar SnS2-reduced graphene oxide material reported previously by this team. The behaviour of the Sb2S3-based electrodes is assessed in both 1 M KPF6in ethylene carbonate-diethyl carbonate and 1 M KPF6in 1,2-dimethoxyethane electrolytes. Depotassiation capacities in excess of 650 mA h g−1are recorded for the composite electrodes, superior not only to SnS2-based electrodes but also to all previously reported Sb2S3-containing electrode materials for potassium-ion batteries. In order to establish insights into the reaction mechanism of the Sb2S3phase with potassium, post-cycling X-ray diffraction andin situtransmission electron microscopy are utilised. The recorded data suggest the presence of antimony alloys and potassium polysulphides as reaction products and intermediates; a possible conversion-alloying reaction mechanism is discussed. The results indicate that a capacity higher than previously believed is achievable in the Sb2S3active component of potassium-ion battery electrodes.</p

Pseudorapidity densities of charged particles with transverse momentum thresholds in pp collisions at √ s = 5.02 and 13 TeV

The pseudorapidity density of charged particles with minimum transverse momentum (pT) thresholds of 0.15, 0.5, 1, and 2 GeV/c is measured in pp collisions at the center of mass energies of √s=5.02 and 13 TeV with the ALICE detector. The study is carried out for inelastic collisions with at least one primary charged particle having a pseudorapidity (η) within 0.8pT larger than the corresponding threshold. In addition, measurements without pT-thresholds are performed for inelastic and nonsingle-diffractive events as well as for inelastic events with at least one charged particle having |η|2GeV/c), highlighting the importance of such measurements for tuning event generators. The new measurements agree within uncertainties with results from the ATLAS and CMS experiments obtained at √s=13TeV.