Search results for "ADVANTAGES"

showing 8 items of 18 documents

Rateless Codes Performance Analysis in Correlated Channel Model for GEO Free Space Optics Downlinks

2012

Settore ING-INF/03 - TelecomunicazioniFree Space Optics (FSO) technologies for satellite communications offer several advantages: wide bandwidth high rate capability immunity to electromagnetic interference and small equipment size. Thus they are suitable for inter-satellite links deep space communications and also for high data rate ground-to-satellite/satellite-to-ground communications. Nevertheless FSO links suffer impairments that cause power signal degradation at the receiver. Scattering and absorption cause power signal attenuations predictable by suitable deterministic models. Optical turbulence causes random irradiance fluctuations which can generate signal fading events and can thereby only be predicted by statistical models. Attenuation and fading events can corrupt FSO links and so it would be recommended to add mitigation error codes on the communication link. FSO channel can be described as an erasure channel: fading events can cause erasure errors. We have identified in rateless codes (RCs) a suitable solution to be employed in FSO links. RCs do not need feedback and they add a redundant coding on the source data that allows the receiver to recover the whole payload despite erasure errors. We implemented two different of rateless codes: Luby Transform (LT) and Raptor. We analyzed their performances on a simulated turbulent GEO FSO downlink (1 Gbps - OOK modulation) at a 106 μm wavelength and for different values of zenith angles. Assuming a plane-wave propagation and employing Hufnagel-Valley we modeled the downlink using: 1) a temporal correlated channel model based on Gamma-Gamma probability distribution and 2) an irradiance covariance function that we converted on a time function using Taylor frozen eddies hypothesis. Our new channel model is able to simulate irradiance fluctuations at different turbulence conditions as it will be shown in the full paper. We will also report performance results of LT and Raptor codes at overhead range varying between 0 and 50% and for different values of source packets.Settore ING-INF/01 - Elettronica
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Rapid and eco-friendly synthesis of graphene oxide-silica nanohybrids

2014

The increasing interest in Graphene oxide (GO) is due to many issues: the presence of both sp2-conjugated atoms and oxygen-containing functional groups provides a strong hydrophilicity and the possibility to further functionalize it with other molecules (i.e. π-π interactions covalent attachment etc.) [1]. Furthermore since the GO is biocompatible and noncytotoxic many studies have been recently focused on the development of GO-based nanodevices for bioimaging DNA detection drug delivery. Due to their low cytotoxicity and large internal surface area silica nanoparticles have been taken into account as promising material for biolabeling and drug loading/delivery. Particular consideration has recently been demonstrated for GO-silica composites because of the potentialities for electrical applications their chemical inertia and stability toward ions exposure. The possibility to combine the extraordinary properties of GO and silica offers several advantages for the realization of nanoprobes for biological applications and of biosensor [12]. The strategy for the fabrication of GO-nanosilica nanohybrids can be schematized as follows: (i) synthesis of GO by oxidizing graphite powder with the method described by Marcano et al. [3] (ii) Preparation of oxygen-loaded silica nanoparticles by thermal treatments in controlled atmosphere in order to induce high NIR emission at 1272 nm from high purity silica nanoparticles. (iii) preparation of GrO-silica nanohybrid films via rapid solvent casting in water. The nanohybrids were tested by XPS FTIR Raman analysis UV photoluminescence analysis TGA Zeta potential measurements electrical tests AFM and SEM. Several nanohybrids were prepared by combining two different typologies of GO and two different samples of silica.
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Biogaz - potencjalne źródło energii

2018

W artykule zaprezentowano właściwości biogazu oraz sposób jego produkcji wraz ze szczegółową charakretystyką wybranych substratów wykorzystywanych do jego wytwarzania. Przedstawiono również technologie produkcji biogazu: mokrą oraz suchą z uwzględnieniem ich najważniejszych wad i zalet. Scharakteryzowano aspekty społeczne, środowiskowe i ekonomiczne, które należy brać pod uwagę podczas planowania budowy biogazowni oraz przeanalizowano obecny rynek biogazowy w Polsce.

advantages and disadvantages of biogas productionbiogas productionwady i zalety produkcji biogazutechnologie produkcji biogazubiogasbiogas production technologies cornwytwarzanie biogazubiogaz
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Students' school‐level symptoms mediate the relationship between a school's observed moisture problems and students’ subjective perceptions of indoor…

2020

Moisture damage can influence the subjective assessment of indoor air quality (subjective IAQ) in various ways. We studied whether the frequency of symptoms reported across students at school level mediates the relationship between observed mold and dampness in a school building and students' subjective IAQ. To answer this research question, we tested a multilevel path model. The analyzed data were created by merging two nationwide data sets: (a) survey data from students, including information on subjective IAQ (N = 24,786 students); (b) data from schools, including information on mold and dampness in a school building (N = 222). After the background variables were adjusted, schools' obser…

dampnessEnvironmental Engineering010504 meteorology & atmospheric sciencesKansanterveystiede ympäristö ja työterveys - Public health care science environmental and occupational healthschoolSubjective perceptioneducationAir MicrobiologyCHILDRENschools010501 environmental sciences01 natural sciencesSick building syndromeIndoor air qualitySurveys and QuestionnairesHumansEXPOSURESchool levelStudents0105 earth and related environmental sciencesENVIRONMENTAL-QUALITYSchools4. EducationMultilevel modelFungitechnology industry and agriculturePublic Health Environmental and Occupational HealthBuilding and ConstructionFRAMEWORK3142 Public health care science environmental and occupational healthSICK-BUILDING SYNDROMEADVANTAGESAir Pollution IndoorODORindoor environmental problemsMultilevel AnalysisASTHMAsymptomsmultilevel analysisPerceptionHEALTHMoisture DamagePsychologyindoor air qualityClinical psychologyIndoor Air
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The adoption of the Euro by Romania

2013

As Romania has joined the European Union, the European currency must be adopted even though it may raise some problems regarding conversion, the impact on goods and services expenses on the interior market having a direct effect on the population and the national economy because we don’t know which the trajectory of the Euro will be. This paper takes a look at the advantages and disadvantages of the adoption of the unique currency in our country taking into account the time factor and the behaviour we must have regarding the Euro, establishing the issues we must take a close look at when the initial term of adoption must be respected.

jel:G18time conversion evaluation advantages disadvantages impact economy.Sibiu Alma Mater University Journals ? Series A. Economic Sciences
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Dictamen profesional sobre la fusión y escisión como extrategias alternativas en un grupo de sociedades

2021

This work is a professional, legal opinion which sets out two alternative strategies (merger by absorption and partial demerger) in order to bring together the different areas of activity of the various companies in a group of companies. The aim is to provide solutions to the questions raised by customers and, therefore, to set out clearly and simply the procedure to be followed in each of the strategies, weighing up the advantages and disadvantages from each of them

legal opinion which sets out two alternative strategies (merger by absorption and partial demerger) in order to bring together the different areas of activity of the various companies in a group of companies. The aim is to provide solutions to the questions raised by customers and:CIENCIAS JURÍDICAS [UNESCO]Proyecto de fusión.MergerExchange rateweighing up the advantages and disadvantages from each of them : Modificaciones estructuralesEscisiónUNESCO::CIENCIAS JURÍDICASModificaciones estructurales [weighing up the advantages and disadvantages from each of them]Merger plan 676 747Fusiónto set out clearly and simply the procedure to be followed in each of the strategies2070-8157 22082 Revista Boliviana de Derecho 565487 2021 31 7730075 Dictamen profesional sobre la fusión y escisión como extrategias alternativas en un grupo de sociedades Bueno BiotthereforeStructural modificationsAlvaro This work is a professionalTipo de canjeGroup of companiesDemerger
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Elektroniczny system przeprowadzania egzaminu zawodowego

2017

Rosnąca rola nowych technologii spowodowała zmiany w sposobie przeprowadzania egzaminu zawodowego. Jedną z nich jest możliwość przeprowadzania egzaminu teoretycznego w wersji elektronicznej. W opracowaniu przedstawione zostały procedury związane z tą formą zewnętrznego oceniania uczestników kształcenia zawodowego. Zamieszczone zostały również dane statystyczne obrazujące odsetek szkół korzystających z tego rozwiązania.

operator egzaminuvocational examadvantages and disadvantages of the electronic examexam structureexam operatorvocational educationegzamin zawodowystruktura egzaminu zawodowegowady i zalety egzaminu elektronicznegokształcenie zawodoweEdukacja -Technika - Informatyka
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Vārdu krājumu novērtējums ar dažādu testēšanu paņēmienu izmantošanu

2016

Darbā tika pētītas vārdu krājuma testēšanas paņēmienu priekšrocības un trūkumi un visefektīvākais un drošākais paņēmiens vārdu krājuma pārbaudei mācību apstākļos. Pētījuma rezultāti spēj veicināt izvēli par labu konkrētam testēšanas paņēmienam, saskaņā ar novērtēšanas veidu un mērķi, tēmu, mērķauditoriju un vidi. Darba teorētiskā daļa ir balstīta uz Arthur Hughes (2003), Scott Thornbury (2002), John Read (2000) un Penny Ur (1999) teorijas. Gadījuma metodes ietvaros tika vadīta mācību nodarbība, pēc kuras studentu zināšanas tika novērtētas ar autores izstrādāto testa palīdzību. Kvantitatīva analīze tika pielietota testa rezultātu noteikšanā un uzticamības mērīšanā, turklāt kvalitatīva analīz…

vocabulary assessmentValodniecībamatchingadvantages and drawbackstesting techniquesvocabulary
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