393 research outputs found
L'Herència Bizantina a l'Arquitectura proto-Otomana: Nicea, Prusa, Belakoma & Constantinoble al s. XIV-XV
Treballs Finals de Grau d'Història de l'Art, Facultat de Geografia i Història, Universitat de Barcelona, Curs: 2013-2014, Tutora: Rosa TerésDes del meu punt de vista, una de les bases de la nostra cultura és l'Imperi bizantí. Si cal buscar un origen, si no fos la cultura hel·lènica, seria sense cap dubte l'imperi bizantí. Però, avui en dia no podem ignorar que els turcs nòmades porten més de 1000 anys a l’Àsia Menor. Totes dues parts van crear una nova cultura, la qual és una fusió. I les fusions sempre són molt més riques, molt més especials. L’objectiu d’aquest treball és mostrar la riquesa de l’arquitectura a l’època proto-otomana, durant els seus primers moments de confrontació
Non-Orthogonal Multiple Access (NOMA) for 5G Networks
In this chapter, we explore the concept of non-orthogonal multiple access (NOMA) scheme for the future radio access for 5G. We first provide the fundamentals of the technique for both downlink and uplink channels and then discuss optimizing the network capacity under fairness constraints. We further discuss the impacts of imperfect receivers on the performance of NOMA networks. Finally, we discuss the spectral efficiency (SE) of the networks that employ NOMA with its relations with energy efficiency (EE). We demonstrate that the networks with NOMA outperform other multiple access schemes in terms of sum capacity, EE and SE
OFDM based visible light broadcasting systems
Visible light communication (VLC) involves the use of light emitting diode (LED)-
based illumination infrastructure for communication purposes [1]. Recent experimental studies on VLC
have demonstrated data speeds more than 3 Gigabits per second [2]. Although indoor spaces usually have
more than one light source, most of the existing works on VLC in the current literature consider point-topoint
communication and few efforts have been made on the scenarios with multiple transmitters. In this
work, we consider a broadcasting scenario in which multiple transmitters (light sources) simultaneously
emit the same information using orthogonal frequency division multiplexing (OFDM)
OFDM based visible light broadcasting systems
Visible light communication (VLC) involves the use of light emitting diode (LED)-
based illumination infrastructure for communication purposes [1]. Recent experimental studies on VLC
have demonstrated data speeds more than 3 Gigabits per second [2]. Although indoor spaces usually have
more than one light source, most of the existing works on VLC in the current literature consider point-topoint
communication and few efforts have been made on the scenarios with multiple transmitters. In this
work, we consider a broadcasting scenario in which multiple transmitters (light sources) simultaneously
emit the same information using orthogonal frequency division multiplexing (OFDM)
Centralized Light Access Network (C-LiAN): A Novel Paradigm for Next Generation Indoor VLC Networks
Visible light communication (VLC) builds upon the idea of using existing lighting infrastructure for wireless data transmission. In a conventional VLC network, each light fixture acts as an access point (AP) which are connected to each other through electrical grid as well as data backbone. These VLCenabled fixtures consist baseband unit (BBU) followed by the optical front-end (OFE). In this paper, we propose the so-called Centralized Light Access Network (C-LiAN) which aggregates all AP computational resources into a central pool that is managed by a centralized controller. Unlike the distributed architecture where each light fixture performs both baseband processing
and optical transmission/reception, the centralized architecture employs “dummy” fixtures with a VLC OFE. Moving the baseband processing to a central pool reduces the associated cost and complexity of each VLC-enabled LED luminary. It further enables joint processing of signals from different APs making possible an efficient implementation of joint processing, offloading, handover, interference management, scheduling and resource management algorithms. As an example to demonstrate
the virtues of C-LiAN, we further present the performance of Coordinated Multi-point Transmission (CoMP) and Enhanced ICIC (eICIC) with almost blank subframe (ABSF) techniques originally proposed for LTE-A in the context of indoor VLC networks
Problem Solving as an Encoding Task: A Special Case of the Generation Effect
Recent evidence suggests that solving problems through insight can enhance long-term memory for the problem and its solution. Previous findings have shown that generation of the solution as well as experiencing a feeling of Aha! can have a beneficial relationship to later memory. These findings lead to the question of how learning in problem-solving tasks in which a novel solution needs to be generated—such as in tasks used to study insight—differs from the classical generation effect. Because previous studies on learning from insight on one hand and the generation effect on the other hand have measured different types of memory, the present study examined two kinds of memory measures: indirect (solving old and new problems at test) and direct (recognition memory). At encoding, we manipulated whether participants had the chance to solve Compound Remote Associates Task items and compared later memory for generated solutions (generate condition) to solutions that were presented after failing to generate one (fail-to-generate condition), and to solutions that were presented without a chance at generation (read condition). Participants also reported if they had an Aha! experience for each problem. While both Aha! experiences and generated solutions were associated with more positive emotional responses, only the generation variable was associated with differences in later memory performance. While attempts to generate had an advantage over the read condition in recognition memory performance (generate \u3e fail-to-generate \u3e read), only when generation was successful did it enhance the solution rate of old items during testing (generate \u3e read \u3e fail-to-generate). Contrary to generation effects with other verbal stimuli, these results suggest that the generation effect in problem-solving tasks in which a novel solution needs to be found differs from the classical generation effect. Seeing a correct solution for a longer time (read) seems in the current case to be more helpful for solving the same problem later on, compared to being presented with the solution after a failed attempt at problem solving
A passive wireless tracking system for indoor assistive monitoring
This paper presents a design concept and implementation of an indoor passive tracking system that utilises an array of Wi-Fi transceivers, and without any electronic device or tag attached to the object being tracked. Such tracking is made possible by exploiting the fundamental characteristic of signal attenuation due to object blocking, i.e. shadowing, that is prevalent in a typical wireless communication system
Cooperative Visible Light Communications With Full-Duplex Relaying
In this paper, we investigate cooperative visible light communication (VLC) system where an intermediate light source acts as a relay terminal. We assume that relay terminal operates in full-duplex mode. In contrast to radio frequency counterparts, full-duplex VLC
terminal is relatively easier to implement due to directive propagation characteristic of light. We first model VLC relay terminal taking into account loop interference channel based on ray tracing simulations. Then, we investigate error rate performance of the relay-assisted VLC system. Our performance evaluations demonstrate the superiority of full-duplex relaying over half-duplex counterpart especially for high modulation sizes
Sample Efficient Interactive End-to-End Deep Learning for Self-Driving Cars with Selective Multi-Class Safe Dataset Aggregation
The objective of this paper is to develop a sample efficient end-to-end deep
learning method for self-driving cars, where we attempt to increase the value
of the information extracted from samples, through careful analysis obtained
from each call to expert driver\'s policy. End-to-end imitation learning is a
popular method for computing self-driving car policies. The standard approach
relies on collecting pairs of inputs (camera images) and outputs (steering
angle, etc.) from an expert policy and fitting a deep neural network to this
data to learn the driving policy. Although this approach had some successful
demonstrations in the past, learning a good policy might require a lot of
samples from the expert driver, which might be resource-consuming. In this
work, we develop a novel framework based on the Safe Dateset Aggregation (safe
DAgger) approach, where the current learned policy is automatically segmented
into different trajectory classes, and the algorithm identifies trajectory
segments or classes with the weak performance at each step. Once the trajectory
segments with weak performance identified, the sampling algorithm focuses on
calling the expert policy only on these segments, which improves the
convergence rate. The presented simulation results show that the proposed
approach can yield significantly better performance compared to the standard
Safe DAgger algorithm while using the same amount of samples from the expert.Comment: 6 pages, 6 figures, IROS2019 conferenc
Utjecaj zamrzavanja i metoda ambalažiranja na udjel organskih kiselina kozjeg sira tijekom skladištenja
Effects of freezing and packaging methods on organic acid content of goat cheese during 12 weeks of storage were determined. Goat cheese milk curds were divided into two batches; one of the batches was directly processed in to goat cheese while the other was frozen at -18 °C and stored for six months and processed into cheese after being thawed. Cheese samples were packed in three parts and stored at 4 °C refrigerated control sample and at -18 °C for six months frozen experimental samples. Cheese samples were packed in three different packaging methods: aerobic, vacuum or modified atmosphere. Citric, malic, fumaric, acetic, lactic, pyruvic and propionic acids were analyzed using HPLC method after 1st, 3rd, 6th, 9th and 12th week of storage period. Lactic acid was the main organic acids while pyruvic acid had the lowest content in all cheese samples. Citric and fumaric acid levels of frozen samples increased during storage whereas malic, acetic, pyruvic and propionic acid amounts were decreased compared to the beginning of storage. Packaging methods and freezing process also effected lactic acid levels statistically (p<0.05). Fumaric, acetic and lactic acid concentration of refrigerated samples were increased but citric, malic and propionic acids decreased during storage. Pyruvic acid level did not change significantly. It was determined that organic acid concentrations were effected by freezing process, storage time and packaging methods significantly (p<0.05).U istraživanju je utvrđen utjecaj zamrzavanja i metoda ambalažiranja na udjel organskih kiselina kozjeg sira tijekom 12 tjedana skladištenja. Gruš sira od kozjeg mlijeka bio je podijeljen u dva dijela - kao kontrolni uzorak pohranjen u hladnjaku na 4 °C i kao zamrznuti eksperimentalni uzorak na -18 °C tijekom šest mjeseci. Nakon toga, sirevi su pakirani trima različitim metodama pakiranja: aerobnom, vakuum ili modificiranom atmosferom. Citronska, jabučna, mravlja, octena, mliječna, pirogrožđana i propionska kiselina analizirane su HPLC metodom nakon 1., 3., 6., 9. i 12. tjedna razdoblja čuvanja. Mliječna kiselina bila je najvažnija organska kiselina, dok je pirogrožđana imala najniži udjel u svim uzorcima sira. Tijekom skladištenja došlo je do povećanja udjela citronske i mravlje kiseline smrznutih uzoraka, dok su udjeli jabučne, octene, pirogrožđane i propionske kiseline opadali u odnosu na početak pohrane. Metode pakiranja i proces zamrzavanja također su statistički utjecali na udjel mliječne kiseline (p<0,05). Koncentracije mravlje, octene i mliječne kiseline ohlađenih uzoraka bile su povećane, dok su citronske, jabučne i propionske kiseline opadale tijekom skladištenja. Razina pirogrožđane kiseline nije se značajno promijenila. Utvrđen je statistički značajan utjecaj procesa zamrzavanja, vremena pohrane i metoda pakiranja na koncentracije organskih kiselina (p <0,05)
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