Performance assessment of UK's cellular network for vehicle to grid energy trading : opportunities for 5G and beyond

The proliferation of plug-in electric vehicles (PEV) and advances in high-speed low latency communication networks redefine the relationships between electricity providers and end-users. A group of PEV owners, coordinated by an aggregator, can participate in ancillary energy markets to stabilize electricity grids and, in return, receive payments for services rendered. However, PEVs are typically parked across a dispersed region possibly with diverse signal strength and data rates. Vehicle-to-Grid (V2G) applications have tight latency (e.g., 500 ms to 2 seconds) and packet-loss requirements, hence, the supporting communication infrastructure should be carefully evaluated for real-world implementations. In this paper, we assess the performance of the internet-based 4G cellular network in the United Kingdom to evaluate these key metrics. We develop a low cost and easily deployable testbed platform to collect and analyze the latency and packet loss rate of different package sizes, transport protocols, and signal strengths. Due to the availability of hardware resources and city-wide coverage of 4G networks, a single parking lot to aggregator scenario is emulated. The results show that in most cases current 4G network can deliver packets less than 500ms which is required in fast frequency response applications in the UK. On the other hand, for more complex scenarios such as multi-aggregator to distributed clients, there is a need to use 5G and beyond to meet the latency requirements. To the best of authors' knowledge, this is the first study focusing on the field testing and assessment of an actual internet-based communication network for V2G applications

Signal Processing for Trace-based Anomaly Detection in Embedded Software

Embedded operating systems generate a log of operating system function calls which we refer to as traces. Trace-based anomaly detection deals with the problem of determining whether or not an instance of traces represents a normal execution scenario. Most current approaches focus on application areas outside of the embedded systems domain and thus do not take advantage of the intrinsic properties of this domain. This work introduces Signal Processing for Trace Based Anomaly Detection (SiPTA): a novel technique for offline trace-based anomaly detection that utilizes the intrinsic feature of periodicity present in embedded systems. SiPTA uses discrete-time Fourier transform which is a crucial tool of signal processing theory as an underlying method. This Thesis describes a generic framework for mapping execution traces to channels and signals for further processing. The classification stage of SiPTA uses a comprehensive set of metrics. As this thesis demonstrates, SiPTA is particularly useful for embedded systems. More specifically, we will compare SiPTA with state-of-the-art approaches to trace-based anomaly detection based on the Markov Model and Neural Networks. This thesis also shows the technical feasibility and viability of SiPTA through multiple case studies using traces from a field-tested hexacopter, a mobile phone platform, and a car infotainment unit. In the experiments, our approach outperformed every other tested method

The Effect of the Board Characteristics and Management Entrenchment on Firm Diversification Strategy

The purpose of this paper is to examine the effect of the board characteristics and the management entrenchment on the diversification strategy at firms listed in Tehran Stock Exchange. In this regard, 110 companies were selected for the period 2008-2014. Panel data method was used to test the hypotheses. In order to examine board characteristics, board size and board independence proxies and to review the management entrenchment, CEO duality, managerial ownership and over investment risk were used. For measuring corporate diversification, Herfindahl and entropy were used. The results show that the size and independence board have negative and positive effects on corporate diversification. This means that company diversification is at high level with large boards and low independent board members. The results show that the CEO duality and the increase of over investment risk have a positive effect on corporate diversification, while managerial ownership has no effect on diversification. The results are consistent with agency theory. According to this theory, the increase in the conflict between shareholders and managers makes the internal managers motivated for opportunistic behavior in order to diversify their enterprise

Algorithms for university course scheduling problems

Rad se bavi problemom planiranja predavanja gdje postoji niz kolegija, predavača i učionica. Kolegiji se dodjeljuju i planiraju tako da se maksimalno zadovolje preferencije. Razvijamo matematički model problema u obliku linearnog programa cijelih brojeva. Manji se problem može optimalno riješiti primjenom komercijalnog softvera. Zatim razvijamo tri različite metaheuristike na temelju umjetnih imunih, genetičkih i algoritama simuliranog kaljenje. Te tri metode rješenja opremljene su novim postupcima kao što su operatori kretanja i križanja. Parametri predložene metaheuristike najprije se usklađuju, a zatim procjenjuju optimalnim rješenjima koje je model pronašao. Nadalje se procjenjuju usporedbom njihovih performansi. Eksperimenti pokazuju da je umjetni imuni algoritam uspješniji od drugih algoritama.This paper deals with the problem of course scheduling where we have a set of courses, lecturers and classrooms. Courses are assigned and scheduled in such a way that the total preference is maximized. We develop the mathematical model of the problem in form of a linear integer program. The small sized problem can be solved to optimality using commercial software. We then develop three different metaheuristics based on artificial immune, genetic and simulated annealing algorithms. These three solution methods are equipped with novel procedures such as move and crossing operators. The parameters of the proposed metaheuristics are first tuned, and then they are evaluated with optimal solutions found by the model. They are, furthermore, evaluated by comparing their performance. The experiments demonstrate that the artificial immune algorithm performs better than the other algorithms

Intracerebral atypical calcification in nongalenic pial arteriovenous fistula: a case report

Nongalenic intradural arteriovenous fistulas, although uncommon, are clinically important. Choosing the appropriate therapeutic approach has been a controversial issue within the last decade

Effect of the mechanical activation on size reduction of crystalline acetaminophen drug particles

The decrease in particle size may offer new properties to drugs. In this study, we investigated the size reduction influence of the acetaminophen (C8H9O2N) particles by mechanical activation using a dry ball mill. The activated samples with the average size of 1 μm were then investigated in different time periods with the infrared (IR), inductively coupled plasma (ICP), atomic force microscopy (AFM), and X-ray diffraction (XRD) methods. The results of the IR and XRD images showed no change in the drug structure after the mechanical activation of all samples. With the peak height at full width at half maximum from XRD and the Scherrer equation, the size of the activated crystallite samples illustrated that the AFM images were in sound agreement with the Scherrer equation. According to the peaks of the AFM images, the average size of the particles in 30 hours of activation was 24 nm with a normal particle distribution. The ICP analysis demonstrated the presence of tungsten carbide particle impurities after activation from the powder sample impacting with the ball and jar. The greatest reduction in size was after milling for 30 hours

One-pot, four-component synthesis of novel cytotoxic agents 1-(5-aryl-1,3,4-oxadiazol-2-yl)-1-(1H-pyrrol-2-yl)methanamines

A series of N-benzyl-1-(5-aryl-1,3,4-oxadiazol-2-yl)-1-(1H-pyrrol-2-yl)methanamines were synthesized via one-pot reaction of appropriate benzylamine, pyrrole-2-carbaldehyde, (N-isocyanimino)triphenylphosphorane, and a carboxylic acid. The anti-tumor potential of title compounds was tested against several cancer cell lines by using MTT assay. Some tested compounds including 5e, 5p and 5q exhibited comparable or better cytotoxic activity against A549, HT29 or HT1080 cells in comparison to the reference drug doxorubicin. Also, the cytotoxic activity of compounds 5d and 5n against MCF-7 was better than that of doxorubicin. Compound 5n with IC50 value of 4.3 mM was 4-fold more potent than doxorubicin. The structureeactivity relationship study revealed that the introduction of halogen atoms on both 5-phenyl ring and N-benzyl part improved the cytotoxic activity against all tested cell lines

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

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