Adaptive and Robust Fault-Tolerant Tracking Control of Contact force of Pantograph-Catenary for High-Speed Trains

Abstract This paper presents a modified multi-body dynamic model and a linear time-invariant model with actuator faults (loss of effectiveness faults, bias faults) and matched and unmatched uncertainties. Based on the fault model, a class of adaptive and robust tracking controllers are proposed which are adjusted online to tolerate the time-varying loss of effectiveness faults and bias faults, and compensate matched disturbances without the knowledge of bounds. For unmatched uncertainties, optimal control theory is added to the controller design processes. Simulations on a pantograph are shown to verify the efficiency of the proposed fault-tolerant design approach

When Mobile Blockchain Meets Edge Computing

Blockchain, as the backbone technology of the current popular Bitcoin digital currency, has become a promising decentralized data management framework. Although blockchain has been widely adopted in many applications, e.g., finance, healthcare, and logistics, its application in mobile services is still limited. This is due to the fact that blockchain users need to solve preset proof-of-work puzzles to add new data, i.e., a block, to the blockchain. Solving the proof-of-work, however, consumes substantial resources in terms of CPU time and energy, which is not suitable for resource-limited mobile devices. To facilitate blockchain applications in future mobile Internet of Things systems, multiple access mobile edge computing appears to be an auspicious solution to solve the proof-of-work puzzles for mobile users. We first introduce a novel concept of edge computing for mobile blockchain. Then, we introduce an economic approach for edge computing resource management. Moreover, a prototype of mobile edge computing enabled blockchain systems is presented with experimental results to justify the proposed concept.Comment: Accepted by IEEE Communications Magazin

Competition and Cooperation Analysis for Data Sponsored Market: A Network Effects Model

The data sponsored scheme allows the content provider to cover parts of the cellular data costs for mobile users. Thus the content service becomes appealing to more users and potentially generates more profit gain to the content provider. In this paper, we consider a sponsored data market with a monopoly network service provider, a single content provider, and multiple users. In particular, we model the interactions of three entities as a two-stage Stackelberg game, where the service provider and content provider act as the leaders determining the pricing and sponsoring strategies, respectively, in the first stage, and the users act as the followers deciding on their data demand in the second stage. We investigate the mutual interaction of the service provider and content provider in two cases: (i) competitive case, where the content provider and service provider optimize their strategies separately and competitively, each aiming at maximizing the profit and revenue, respectively; and (ii) cooperative case, where the two providers jointly optimize their strategies, with the purpose of maximizing their aggregate profits. We analyze the sub-game perfect equilibrium in both cases. Via extensive simulations, we demonstrate that the network effects significantly improve the payoff of three entities in this market, i.e., utilities of users, the profit of content provider and the revenue of service provider. In addition, it is revealed that the cooperation between the two providers is the best choice for all three entities.Comment: 7 pages, submitted to one conferenc

Reflexões sobre a tradução jurídica português-chinês: a tradução do Código Civil de Macau sob a influência de factores sociais

A tradução jurídica chinês-português desempenha um papel crítico no processo de aprofundamento e expansão do uso comum do chinês juntamente com o do português em Macau e em intercâmbios e comunicações entre a China e os países lusófonos. Esta dissertação visa analisar as influências de factores sociais na tradução jurídica de Macau e explorar as estratégias para lidar com elas. Para este efeito, é examinado em especial o Código Civil de Macau como objecto de investigação. O Código Civil de Macau é, por um lado, uma declaração de protecção dos legítimos direitos e interesses das pessoas, estando intimamente relacionado com as pessoas na sociedade, e, por outro, estabelece as normas de comportamento e cumprimento básico para diversas actividades civis dos sujeitos civis. Através da comparação e análise crítica da actual versão bilingue do Código Civil de Macau, a dissertação estuda vários factores sociais, nomeadamente políticos e relativos ao ambiente linguístico e a perspectiva de pensamento moldada por cultura, que afectam as decisões tomadas durante a tradução jurídica, assim como as teorias, métodos e estratégias de tradução aplicadas, a fim de lidar com os problemas suscitados. Por meio da análise acima mencionada, chega-se à conclusão de que, no processo de tradução jurídica, os factores sociais são de grande relevância para a tradução, o que se reflecte principalmente na escolha de palavras e terminologia na língua de chegada e na forma de construção de frases. Nesse processo, além de se explorar a conversão equivalente ao nível das palavras e das frases, é feita uma análise sobre a intenção legislativa e os efeitos jurídicos que a tradução correspondente pode produzir. No final desta dissertação, com base nas características especiais formada em Macau durante o processo de tradução jurídica, explora-se os métodos e as estratégias mais adequadas para a tradução jurídica português-chinês.Portuguese-Chinese legal translation plays a critical role in the process of deepening and expanding the common use of Chinese together with that of Portuguese in Macau and in interchanges and communications between China and Portuguese-speaking countries. This dissertation aims to analyze the influence of social factors in the legal translation of Macao and to explore the strategies to deal with them. For this purpose, the Civil Code of Macau is studied. The Civil Code of Macau, on the one hand, is a declaration of protection of the legitimate rights and interests of people, being closely related to people in society, and, on the other, it establishes the rules of behavior and basic compliance for various civil activities of the civilian subjects. Through the comparison and critical analysis of the current bilingual versions of the Civil Code of Macau, this dissertation studies several social factors, namely political and related to the linguistic environment and the perspective of thinking shaped by culture, which affect decisions taken during the process of legal translation, as well as the theories, methods and translation strategies applied in order to deal with the problems raised. Through the aforementioned analysis, it is concluded that, in the process of legal translation, social factors are of great relevance to the translation, which is mainly reflected in the choice of words and terminology in the language of arrival and in the form of sentence construction. In this process, in addition to an exploration of the equivalent conversion at the level of words and phrases, an analysis is carried out about the intention and the legal effects which the corresponding translation can produce. At the end of this dissertation, based on the special characteristics formed in Macau during the legal translation process, appropriate methods and strategies for Portuguese-Chinese legal translation are explored

FPTN: Fast Pure Transformer Network for Traffic Flow Forecasting

Traffic flow forecasting is challenging due to the intricate spatio-temporal correlations in traffic flow data. Existing Transformer-based methods usually treat traffic flow forecasting as multivariate time series (MTS) forecasting. However, too many sensors can cause a vector with a dimension greater than 800, which is difficult to process without information loss. In addition, these methods design complex mechanisms to capture spatial dependencies in MTS, resulting in slow forecasting speed. To solve the abovementioned problems, we propose a Fast Pure Transformer Network (FPTN) in this paper. First, the traffic flow data are divided into sequences along the sensor dimension instead of the time dimension. Then, to adequately represent complex spatio-temporal correlations, Three types of embeddings are proposed for projecting these vectors into a suitable vector space. After that, to capture the complex spatio-temporal correlations simultaneously in these vectors, we utilize Transformer encoder and stack it with several layers. Extensive experiments are conducted with 4 real-world datasets and 13 baselines, which demonstrate that FPTN outperforms the state-of-the-art on two metrics. Meanwhile, the computational time of FPTN spent is less than a quarter of other state-of-the-art Transformer-based models spent, and the requirements for computing resources are significantly reduced