Academic literature on the topic 'WI 000'

This study aims to investigate the relative impact of Wi-Fi on consumers’ hotel bookings. It investigates two dimensions of Wi-Fi (price and reviews) in relation to overall hotel ratings, brand, and price per night. A scenario was arranged whereby participants (n = 120) booked a hotel room online. The results (r = .991, p = .000) of a conjoint analysis show that Wi-Fi price and Wi-Fi reviews affect the consumers’ booking, but not as much as hotel ratings and price per night. When looking only at Wi-Fi, results show that previous guests’ Wi-Fi reviews have a higher impact on booking than Wi-Fi price. Further analysis shows that Wi-Fi can be a “deal breaker” in a competitive and/or undifferentiated market. We propose that the impact of Wi-Fi can be understood as rule-governed behavior. Consequently, behavioral understanding of the impact of Wi-Fi could aid hotel managers in developing more effective marketing strategies.

Measles was very common in Belgium before 1985, affecting 95% of children before they reached the age of 15 years. In 1984 the incidence of measles, calculated using data from a general practitioner surveillance system, was 823/100 000 inhabitants (2). Wi

Background and study aimsPost-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) is a complication associated with important morbidity, occasional mortality and high costs. Preventive strategies are suboptimal as PEP continues to affect 4% to 9% of patients. Spraying epinephrine on the papilla may decrease oedema and prevent PEP. This study aimed to compare rectal indomethacin plus epinephrine (EI) versus rectal indomethacin plus sterile water (WI) for the prevention of PEP.Patients and methodsThis multicentre randomised controlled trial included patients aged >18 years with an indication for ERCP and naive major papilla. All patients received 100 mg of rectal indomethacin and 10 mL of sterile water or a 1:10 000 epinephrine dilution. Patients were asked about PEP symptoms via telephone 24 hours and 7 days after the procedure. The trial was stopped half way through after a new publication reported an increased incidence of PEP among patients receiving epinephrine.ResultsOf the 3602 patients deemed eligible, 3054 were excluded after screening. The remaining 548 patients were randomised to EI group (n=275) or WI group (n=273). The EI and WI groups had similar baseline characteristics. Patients in the EI group had a similar incidence of PEP to those in the WI group (3.6% (10/275) vs 5.12% (14/273), p=0.41). Pancreatic duct guidewire insertion was identified as a risk factor for PEP (OR 4.38, 95% CI (1.44 to 13.29), p=0.009).ConclusionSpraying epinephrine on the papilla was no more effective than rectal indomethacin alone for the prevention of PEP.Trial registration numberThis study was registered with ClinicalTrials.gov (NCT02959112).

Ovarian stimulation (OS) by exogenous gonadotropin enhances the availability of mammalian oocytes but compromises their developmental competence (Combelles and Albertini 2003 Biol. Reprod. 68, 812–821). Recently, several studies have reported mitochondrial function-related abnormalities in oocytes after single and repeated OSs. Because mitochondria can directly influence fertilization outcomes (El Shourbagy et al. 2006 Reproduction 131, 233–245), this study aimed to determine the relationship between mitochondria-related parameters and developmental competence on the basis of ATP content, mitochondrial DNA (mtDNA) copy number, mitochondrial distribution, and IVF results for oocytes after repeated OSs. Ovulated oocytes were recovered from ICR female mice treated with 7.5 IU of eCG and 5 IU of hCG at an interval of 48 h in 1 (control) to 3 stimulation cycles, which were performed at intervals of either 5 or 10 d (n = 15–25 in each treatment group). The ATP content in oocytes was determined using a luminometer and commercial kits (BacTiter-Glo; Promega, WI, USA; n = 15–29 in each treatment group). The mtDNA copy number in oocytes was quantified by performing absolute quantification with real-time PCR (n = 4–8 in each treatment group). Mitochondrial distribution in oocytes stained by rhodamine123 was observed under a confocal microscope (n = 12–26 in each treatment group). These analyses were performed only for morphologically normal oocytes. The data were analyzed by one-way ANOVA, followed by Fisher’s least significant difference, or by the chi-square test. Some mice did not ovulate in the third stimulation cycle for both intervals (5-d interval, 32%; 10-d interval, 80%). The mean numbers of ovulated oocytes gradually decreased with progression of the stimulation cycles. The ATP content of the oocytes significantly decreased both in the second and third stimulation cycles, performed with a 5-d interval (control, 1.038 ± 0.117 pmol; second cycle, 0.852 ± 0.189 pmol; third cycle, 0.932 ± 0.272 pmol). The mean mtDNA copy number in oocytes did not change significantly but varied widely in the third stimulation cycle (control, 146 000 ± 21 000; 5-d interval, 135 000 ± 35 000; 10-d interval: 148 000 ± 50 000; mean ± SD). The mitochondrial staining patterns were classified into homogeneous, aggregation, and perinuclear accumulation. The rates of aggregation and perinuclear accumulation increased after repeated stimulation cycles. The blastocyst rates did not significantly differ among the treatment groups after IVF (75–82%). Repeated OSs not only decreased the number of ovulated oocytes but also caused changes related with mitochondrial function, even in the morphologically normal ovulated oocytes. Translocation of active mitochondria, which are associated with energy production, has some functional correlation with successful pre-implantation development (Suzuki et al. 2006 J. Mamm. Ova. Res. 23, 128–134). Changes in mitochondrial distribution might compensate for the negative effect of the decrease in ATP content and low mtDNA copy number after repeated OSs to help reach the blastocyst stage.

For over a decade it has been possible to externally sex monomorphic birds using PCR. A major drawback of the protocol developed by Richard Griffiths is that DNA from at least 20 000 cells is needed (Griffiths et al. 1996 Proc. Royal Soc. London B 263, 1249–1254). Our study attempted to decrease the number of cells required. A sequence within the chromobox-helicase-DNA-binding (CHD) gene, located on the sex chromosomes of all avian species, was amplified. The sequence lengths were 362 and 354 base pairs for the CHD-W and CHD-Z, respectively. The polyacrylamide gel electrophoresis (PAGE) purified primers used were 5´-TCTGCATCGCTAAATCCTTT-3´ and 5´-CTCCCAAGGATGAGRAAYTG-3´ (2.5 µm) (IDT, Inc., San Jose, CA, USA). All assays used Taq DNA polymerase (2.7 U) (M0273L, New England BioLabs, Ipswich, MA, USA) and deoxyribonucleotides (5 µm) (C01581, GenScript Corp, Piscataway, NJ, USA). Lymphocytes from chickens (Gallus domesticus) (10 cells/2 µL) were used as the DNA source for all experiments. Assays were run with positive and negative DNA controls. The DNA was replicated in a Corbett Rapid Thermocycler (Model FTS-IS, Corbett Research, Sydney, Australia) in 20 µL volumes with an annealing temperature of 48�C. All of the PCR products were separated using PAGE. An 8% gel (17:1, con- to bis-acrylamide) with 10 mm TRIS (pH 8) was formed in an agarose gel chamber (M12 Electrophoresis Unit, Edvotek, Bethesda, MD, USA) under Ar. The gel was placed in 10 mm TRIS (pH 8) in the electrophoresis apparatus and the PCR products were added to wells. The applied voltage was 200 and the duration was 2 h (PS500ST, Hoefer Scientific Instruments, San Francisco, CA, USA). The gel was stained for 30 min in 1.25 µm ethidium bromide in 100 mL of 10 mm TRIS (pH 8). Destaining was carried out over 45 min in 100 mL of H2O. The gel was viewed using a transilluminator (3–300, Fotodyne, Hartland, WI, USA) and photographed with an Olympus digital camera. An initial experiment established Griffiths' assay in our lab. Results were consistent with published data, albeit with the same troubling signal-to-noise problems. No signals were observed in assays with less than 20 000 cells. The next experiment compared the use of Griffiths' amplification buffer to a buffer we developed, Bart: 50 mm barbital, 1% dextran T-500, 50 mm KCl, 2.5 mm MgCl2, and 0.035% 2-mercaptoethanol. Signals were produced and a working assay was established with only 10 cells needed, significantly fewer cells than the 20 000 cells necessary for Griffiths' protocol. It was possible to increase the number of productive replication cycles from 35 to 45 without generation of noise. In fact, use of Bart eliminated primer-generated noise, leaving only sexing bands in the gel. Interestingly, when Bart was used with 20 000 cells, no signals were observed. Assays incorporating Bart were run in triplicate and signals were consistently observed. Reduction in the number of cells required for avian sex determination provides potential applications for the sexing of embryos or sexing from a single down feather. Our assay makes sex determination prior to hormonal treatment simple. We are currently replacing the use of the CHD gene with a conserved W-specific sequence.

ObjectiveAssistance Publique-Hôpitaux de Paris (AP-HP), the leading university hospital in France, proposed to offer its services to candidate on a voluntary basis for a hospitality award, certifying compliance to a 240-item home-made questionnaire designed by healthcare providers and patients’ representatives. It combined an objective examination of the services and patients’ questionnaires, covering seven domains: reception and information from admission to discharge; cleanliness, comfort and environment; proposed services (eg, access to Wi-Fi); culture, relaxation and well-being; meals; linen and relationship quality with hospital staff. The procedure was completed in two steps: an initial self-evaluation to detect improvable deficiencies, followed by an awarding visit. A service received the hospitality award if at least 80% of the reference criteria were met during this second evaluation. Here, we describe the construction of this hospitality awards programme and present a comparison of the scores obtained during the two steps.Design and methodsRetrospective comparison by usual statistical tests.SettingAP-HP, grouping 39 university hospitals (21 000 beds, 8 million annual patient visits).ParticipantsThe 211 services from 29 different hospitals engaged in the procedure (2017–2019).ResultsOnly one service did not get the award (self-evaluation 83%, visit score 79%). The score was higher during the awarding visit (89.0%±5.6%) than during self-evaluation (85.5%±4.3%, n=211, p<0.00001), with increased scores for the following domains (p<0.005): patient reception and information; cleanliness, comfort and environment; proposed services; culture, relaxation and well-being.Conclusion(1) Internal self-evaluation is feasible. (2) By diffusing criteria of hospitality, the procedure had a pedagogical value leading to rapid and significant improvements. (3) This quality assessment procedure results in an award that can be posted in the departments. By appealing to pride, this procedure should promote hospitality in hospitals.

Inter-Vehicular Communication is an optimistic technology to enhance road safety. The wireless medium often used to exchange vital information. Wi-Fi is also used to share the information, but it required an access point hardware to communicate. Wi-Fi Direct enabled the device exchange information without a hardware access point. Over the last decades, the usage of wireless technology has been increased and transformed the way electronic devices interact and communicate. Wi-Fi Direct technology provides peer-to-peer communication. So, Wi-Fi is highly applicable for car-to-car communication because of its High data rate, range, standard usage. Within the framework of this thesis concept of prototyping car-to-car communication by using Wi-Fi Direct service in smartphones. Focus here to optimize resource utilization and to provide basic functionality within the programming mode.

Wireless networks are ubiquitous nowadays and play an increasingly important role in our everyday lives. Many emerging applications including augmented reality, indoor navigation and human tracking, rely heavily on Wi-Fi, thus requiring an even more sophisticated network. One key component for the success of these applications is accurate localization. While we have GPS in the outdoor environment, indoor localization at a sub-meter granularity remains challenging due to a number of factors, including the presence of strong wireless multipath reflections indoors and the burden of deploying and maintaining any additional location service infrastructure. On the other hand, Wi-Fi technology has developed significantly in the last 15 years evolving from 802.11b/a/g to the latest 802.11n and 802.11ac standards. Single user multiple-input, multiple-output (SU-MIMO) technology has been adopted in 802.11n while multi-user MIMO is introduced in 802.11ac to increase throughput. In Wi-Fi’s development, one interesting trend is the increasing number of antennas attached to a single access point (AP). Another trend is the presence of frequency-agile radios and larger bandwidths in the latest 802.11n/ac standards. These opportunities can be leveraged to increase the accuracy of indoor wireless localization significantly in the two systems proposed in this thesis: ArrayTrack employs multi-antenna APs for angle-of-arrival (AoA) information to localize clients accurately indoors. It is the first indoor Wi-Fi localization system able to achieve below half meter median accuracy. Innovative multipath identification scheme is proposed to handle the challenging multipath issue in indoor environment. ArrayTrack is robust in term of signal to noise ratio, collision and device orientation. ArrayTrack does not require any offline training and the computational load is small, making it a great candidate for real-time location services. With six 8-antenna APs, ArrayTrack is able to achieve a median error of 23 cm indoors in the presence of strong multipath reflections in a typical office environment. ToneTrack is a fine-grained indoor localization system employing time difference of arrival scheme (TDoA). ToneTrack uses a novel channel combination algorithm to increase effective bandwidth without increasing the radio’s sampling rate, for higher resolution time of arrival (ToA) information. A new spectrum identification scheme is proposed to retrieve useful information from a ToA profile even when the overall profile is mostly inaccurate. The triangle inequality property is then applied to detect and discard the APs whose direct path is 100% blocked. With a combination of only three 20 MHz channels in the 2.4 GHz band, ToneTrack is able to achieve below one meter median error, outperforming the traditional super-resolution ToA schemes significantly.

Darbe “Modeling and analysis of Wi-Max network data” supažindinama su plačiajuosčio bevielio ryšio technologija – Wi-Max. Analizuojama literatūra, kuri aprašo Wi-Max veikimo principą, nagrinėjami šios technologijos ypatumai, ji lyginama su kitomis bevielio ryšio technologijomis. Apžvelgiamos šios technologijos perspektyvos. Tinklo duomenų modelis suteikia galimybę teikti papildomas paslaugas vartotojams, leidžia stebėti ir analizuoti Wi-Max duomenų perdavimo tinklą. Rementis IEEE 802.16e standartu, sudaryta metodika tinklo duomenų modeliui kurti. Išanalizuota Wi-Max technologijos tinklo duomenų struktūra, kuri sėkmingai pritaikyta tinklo duomenų modelio metodikos kūrimui. Sudarytos tinklo duomenų modelio specifikacijos ir pagal jas sukurtas tinklo duomenų modelis. Atliktas tinklo duomenų modelio eksperimentinis tyrimas ir pateikti šio tyrimo rezultatai. Rementis eksperimento rezultatais įvertintos Wi-Max technologijos realios galimybės.
This master‘s thesis familiarizes with the wireless broadband networking technology – WiMAX. The work includes literature analysis of WiMAX performance principles, research of technological peculiarities and comparison with other wireless technologies. The perspective of this technology is also overviewed. The model of network data allows providing additional services to the customers, as well as monitoring and analyzing of WiMAX data transmission network. The methodology of creating the model is based on IEEE 802.11e standard. Structure of WiMAX data networks is analyzed and successfully applied to implementation of methodology for model of WiMAX network data. The specifications for network data model were created and the model implemented according to them. The experimental analysis of the model was performed and results presented herein. The realistic capabilities of WiMAX technology were evaluated using the results of experiment.

Darbe nagrinėjami bevieliai kompiuteriniai tinklai Wi-Fi ir jų problemos. Nustatomos kelios iš pagrindinių bevielių tinklų problemų. Radijo modulio veikimo režimas yra halfduplex, nepakankamas naudingo srauto perdavimas, srauto klasifikacijos ir prioritetizacijos nebuvimas mano manymu yra pagrindinės bevielio ryšio įrenginių problemos. Bandoma ieškoti problemų sprendimo variantus. Vienas iš galimų sprendimų yra sukurti bevielio ryšio įrenginį, kuris turės šių problemų realizaciją. Ieškoma įrenginiui sukurti būtinų detalių, tokių kaip platforma, radijo modulis, antena ir kitos būtinos detalės. Pirmiausia pasirenkama PC-based platforma dėl to kad turi didesnį produktyvumą ir yra universalesnė. Vienareikšmiškai pasirenkamas 5 GHz radijo dažnis, kadangi įrenginys bus testuojamas ir naudojamas realaus tinklo infrastruktūroje Vilniaus mieste. 2,4 GHz dažnio ruožo naudojimo buvo atsisakyta dėl stipraus užterštumo. Kaip paaiškėjo analizuojamos problemos yra susijusios viena su kita ir reikalauja kompleksinio sprendimo. Buvo nustatyta problemų prigimtis ir jos sprendimas: bendro srauto ribojimas, srautų pagal paskirtį atskyrimas ir jų ribojimas. Ieškomos standartinės ir nestandartinės problemų sprendimo priemonės, tobulinamos, tarpusavyje suderintos ir pritaikytos kuriamai sistemai. Tik realioje tinklo infrastruktūroje su realiais vartotojų generuojamais srautais pavyko nustatyti ir pašalinti trukumus.
This work is an analysis of wireless computer networks Wi-Fi and their problems. Few main wireless networks problems established. Radio module working mode is halfduplex, insufficient transfers of useful data stream, absence of stream classification and prioritisation in my opinion is a main problems of wireless devices. Attempt to search solution of the problems. One of the possible solutions is making an own wireless device witch will have realisation of this problems. Searching for necessary parts to make a device, such as platform, radio module, antenna ant other necessary parts. First of all I have chosen PC-based platform because it has a good productivity ant is more universal. Unambiguous choice was 5 GHz radio frequency, because device will be tested and used in real network infrastructure of Vilnius city. The use of 2,4 GHz radio frequency was rejected because of high radio pollution. It emerged that analysed problems are associated one with another and needs complex solution. Was found nature of this problems and its solutions: total bandwidth shaping, separation of different streams by purpose and their shaping. Searching for standard and nonstandard means to solve such problems, modifying, matching together and adjust to created system. Only in real network infrastructure with real user generated streams was able find and eliminate limitations.

Mobilieji įrenginiai tobulėja ir pateikia vis daugiau galimybių jų vartotojams. Tokie įrenginiai naudojami tiek asmeniniais, tiek darbo tikslais, kas sukelia papildomų saugos grėsmių įmonėms. Esant tokiai situacijai, reikalingos papildomos valdymo priemonės, kurios užtikrintų asmeninių įrenginių saugos konfigūravimą, atitinkantį organizacijos saugos politiką. Organizacijos saugos politika privalo atsižvelgti į dvi pagrindines sritis: organizacijos sistemų saugumą ir mobiliojo įrenginio saugumą. Magistrinio darbo tikslas – išnagrinėti mobiliesiems įrenginiams keliamas grėsmes bei sudaryti mobiliųjų įrenginių saugios konfigūracijos paramos sistemos prototipą.
The mobile industry is evolving rapidly and new mobile devices with sophisticated capabilities are released almost every day. The technical advancements in mobile industry have resulted in increase of security threats and attacks. To provide strong security mechanism a combination of solutions need to be implemented at different levels based on enterprise mobile application security requirements. Enterprise mobile security should ensure two key components: enterprise system security and device security. The aim of this paper is to create secure configuration decision support system prototype for personal devices.

Grâce à l’émergence dans la vie quotidienne des appareils de plus en plus populaires que sont les smartphones et les tablettes, la tâche de postionner l'utilisateur par le biais de son téléphone est une problématique fortement étudiée dans les domaines non seulement de la recherche mais également des communautés industrielles. Parmi ces technologies, les approches GPS sont devenues une norme et ont beaucoup de succès pour une localisation en environnement extérieur. Par contre, le Wi-Fi, les capteurs inertiels et le Bluetooth sont plutôt préférés pour les tâches de positionnement dans un environnement intérieur.Pour ce qui concerne le positionnement des smartphones, les approches basées sur les « empreintes digitales » (fingerprint) Wi-Fi sont bien établies. D'une manière générale, ces approches tentent d'apprendre la fonction de correspondance (cartographie) des caractéristiques du signal Wi-Fi par rapport à la position de l’appareil dans le monde réel. Elles nécessitent généralement une grande quantité de données pour obtenir une bonne cartographie. Lorsque ces données d'entraînement disponibles sont limitées, l'approche basée sur les empreintes digitales montre alors des taux d’erreurs élevés et devient moins stable. Dans nos travaux, nous explorons d’autres approches, différentes, pour faire face à cette problématique du manque de données d'entraînement. Toutes ces méthodes sont testées sur un ensemble de données public qui est utilisé lors d’une compétition internationale à la Conférence IPIN 2016.En plus du système de positionnement basé sur la technologie Wi-Fi, les capteurs inertiels du smartphone sont également utiles pour la tâche de suivi. Les trois types de capteurs, qui sont les accéléromètres, le gyroscope et la boussole magnétique, peuvent être utilisés pour suivre l'étape et la direction de l'utilisateur (méthode SHS). Le nombre d'étapes et la distance de déplacement de l'utilisateur sont calculés en utilisant les données de l'accéléromètre. La position de l'utilisateur est calculée par trois types de données avec trois méthodes comprenant la matrice de rotation, le filtre complémentaire et le filtre de Madgwick. Il est raisonnable de combiner les sorties SHS avec les sorties de Wi-Fi, car les deux technologies sont présentes dans les smartphones et se complètent. Deux approches combinées sont testées. La première approche consiste à utiliser directement les sorties Wi-Fi comme points de pivot pour la fixation de la partie de suivi SHS. Dans la deuxième approche, nous comptons sur le signal Wi-Fi pour construire un modèle d'observation, qui est ensuite intégré à l'étape d'approximation du filtre à particules. Ces combinaisons montrent une amélioration significative par rapport au suivi SHS ou au suivi Wi-Fi uniquement.Dans un contexte multiutilisateur, la technologie Bluetooth du smartphone pourrait fournir une distance approximative entre les utilisateurs. La distance relative est calculée à partir du processus de numérisation du périphérique Bluetooth. Elle est ensuite utilisée pour améliorer la sortie des modèles de positionnement Wi-Fi. Nous étudions deux méthodes. La première vise à créer une fonction d'erreur qui permet de modéliser le bruit dans la sortie Wi-Fi et la distance approximative produite par le Bluetooth pour chaque intervalle de temps spécifié. La seconde méthode considère par contre cette relation temporelle et la contrainte de mouvement lorsque l'utilisateur se déplace. Le modèle d'observation du filtre à particules est une combinaison entre les données Wi-Fi et les données Bluetooth. Les deux approches sont testées en fonction de données réelles, qui incluent jusqu'à quatre utilisateurs différents qui se déplacent dans un bureau. Alors que la première approche n'est applicable que dans certains scénarios spécifiques, la deuxième approche montre une amélioration significative par rapport aux résultats de position basés uniquement sur le modèle d'empreintes digitales Wi-Fi
With the popularity of smartphones and tablets in daily life, the task of finding user’s position through their phone gains much attention from both the research and industry communities. Technologies integrated in smartphones such as GPS, Wi-Fi, Bluetooth and camera are all capable for building a positioning system. Among those technologies, GPS has approaches have become a standard and achieved much success for the outdoor environment. Meanwhile, Wi-Fi, inertial sensors and Bluetooth are more preferred for positioning task in indoor environment.For smartphone positioning, Wi-Fi fingerprinting based approaches are well established within the field. Generally speaking, the approaches attempt to learn the mapping function from Wi-Fi signal characteristics to the real world position. They usually require a good amount of data for finding a good mapping. When the available training data is limited, the fingerprinting-based approach has high errors and becomes less stable. In our works, we want to explore different approaches of Wi-Fi fingerprinting methods for dealing with a lacking in training data. Based on the performance of the individual approaches, several ensemble strategies are proposed to improve the overall positioning performance. All the proposed methods are tested against a published dataset, which is used as the competition data of the IPIN 2016 Conference with offsite track (track 3).Besides the positioning system based on Wi-Fi technology, the smartphone’s inertial sensors are also useful for the tracking task. The three types of sensors, which are accelerate, gyroscope and magnetic, can be employed to create a Step-And-Heading (SHS) system. Several methods are tested in our approaches. The number of steps and user’s moving distance are calculated from the accelerometer data. The user’s heading is calculated from the three types of data with three methods, including rotation matrix, Complimentary Filter and Madgwick Filter. It is reasonable to combine SHS outputs with the outputs from Wi-Fi due to both technologies are present in the smartphone. Two combination approaches are tested. The first approach is to use directly the Wi-Fi outputs as pivot points for fixing the SHS tracking part. In the second approach, we rely on the Wi-Fi signal to build an observation model, which is then integrated into the particle filter approximation step. The combining paths have a significant improvement from the SHS tracking only and the Wi-Fi only. Although, SHS tracking with Wi-Fi fingerprinting improvement achieves promising results, it has a number of limitations such as requiring additional sensors calibration efforts and restriction on smartphone handling positions.In the context of multiple users, Bluetooth technology on the smartphone could provide the approximated distance between users. The relative distance is calculated from the Bluetooth inquiry process. It is then used to improve the output from Wi-Fi positioning models. We study two different combination methods. The first method aims to build an error function which is possible to model the noise in the Wi-Fi output and Bluetooth approximated distance for each specific time interval. It ignores the temporal relationship between successive Wi-Fi outputs. Position adjustments are then computed by minimizing the error function. The second method considers the temporal relationship and the movement constraint when the user moves around the area. The tracking step are carried out by using particle filter. The observation model of the particle filter are a combination between the Wi-Fi data and Bluetooth data. Both approaches are tested against real data, which include up to four different users moving in an office environment. While the first approach is only applicable in some specific scenarios, the second approach has a significant improvement from the position output based on Wi-Fi fingerprinting model only

Comme le Wi-Fi est devenu de plus en plus important dans les réseaux actuels, ainsi que dans les réseaux du futur, de nouvelles exigences " opérateur " se sont apparues afin de supporter les attentes des utilisateurs et de fournir des réseaux Wi-Fi de haute performance. Dans ce contexte, nous étudions plusieurs problèmes liés à la conception et l'optimisation des réseaux Wi-Fi opérateur de nouvelle génération. Dans la première étape, notre objectif est d'améliorer l'expérience utilisateur Wi-Fi et de lui offrir un accès personnalisé et transparent aux réseaux et services Wi-Fi. Pour cela, nous proposons une extension des trames de gestion IEEE 802.11 pour activer la découverte des services locaux avant l'association Wi-Fi, tout en évitant la surcharge du canal. Nous définissons également un ensemble d'étiquettes de service pour identifier d'une manière standardisée les services les plus connus. Dans la deuxième étape, nous adressons les problèmes liés à l'architecture et la gestion du réseau dans un environnement Wi-Fi opérateur de nouvelle génération. Plus précisément, nous proposons, tout d'abord, une nouvelle architecture Wi-Fi qui exploite les concepts de NFV et du Edge Cloud Computing. Nous visons à travers cette architecture à apporter plus d'agilité et d'adaptabilité et d'améliorer la QoS perçue par l'utilisateur en plaçant des fonctions réseau et certains services à proximité de lui. Pour faire face à certains problèmes de gestion dans cette architecture, nous proposons ensuite des stratégies de placement et de provisionnement des fonctions de réseau virtuelles en s'appuyant sur des exigences de QoS
As Wi-Fi is gaining a lot of momentum in today’s networks as well as in future networks, new carrier-grade requirements are emerging to support future user expectations and provide high-performance Wi-Fi networks. In this context, we investigate several problems surrounding the design and optimization of carrier-grade next-generation Wi-Fi networks. In the first stage, our objective is to improve the Wi-Fi user experience and offer to him a personalized and seamless access to Wi-Fi networks and services. For this, we propose an extension to the IEEE 802.11 management frames to enable venue service discovery prior to Wi-Fi association while avoiding channel overhead. We define also a set of extensible service labels to uniquely and globally identify the most known venue-based services. In the second stage, we deal with network architecture and management issues in next-generation carrier Wi-Fi environment. More specifically, we first propose a novel carrier-managed Wi-Fi architecture that leverages NFV and Edge Cloud Computing concepts. We aim through this architecture to bring more agility and adaptability and improve user perceived QoS by placing network functions and certain services close to end-users. To address some major management issues in this proposed architecture, we then propose placement and provisioning strategies of Virtual Network Functions based on QoS requirements. These strategies can also be applied to any edge-central wireless carrier architecture, since they do not make any assumption about the underlying wireless technology

La virtualisation, originalement introduite dans les réseaux pour en réduire les coûts de maintenance et de déploiement, a connu une explosion fulgurante remodelant le paysage des réseaux informatiques et télécoms. La virtualisation permet la mutualisation des ressources physiques pour instancier des machines virtuelles complétement isolées mais puisant leurs ressources du même matériel physique. Plus récemment le NFV (Network Functions Virtualisation) est apparu, et a permis de virtualiser des classes entières de fonctions de nœud de réseau dans des blocs qui peuvent se connecter pour créer des services de communication. Cette thèse s’inscrit dans ce contexte pour virtualiser les nœuds des réseaux d’accès, à savoir les points d’accès Wi-Fi. Le Wi-Fi est devenu la technologie de tous les enjeux pour les opérateurs mobile. Cette technologie leur permet notamment d’y délester une partie du trafic de données clients via des hotspots. Le problème qui se pose dans un tel mécanisme est que les normes Wi-Fi existantes ainsi que les logiciels de gestion de connexion d’un appareil mobile n’ont pas été développés dans l’optique du hotspot. A cet effet, la norme Hotspot2.0 a été créée, pour rendre l’expérience Wi-Fi similaire à celle du cellulaire en termes d’itinérance, de transparence et de sécurité. Nous avons dans nos travaux, appliqué le concept de NFV en virtualisant ces points d’accès Wi-Fi de nouvelle génération. La problématique face à laquelle nous avons été confrontés est la forte sécurité imposée par de tels dispositifs exigeants notamment l’enregistrement et l’installation de certificats de sécurité clients dans les lieux publics. Dans notre thèse nous proposons une architecture innovante permettant le rapatriement de ces éléments de sécurité à travers des bornes NFC. Ces mêmes bornes, dans une volonté d’urbanisation des points d’accès, permettront aux utilisateurs de créer leurs propres points d’accès Wi-Fi virtuels à la volée. Enfin, le dernier aspect de cette thèse touche à la problématique de gérance des entités virtualisées changeant les schémas de communication des réseaux traditionnels. Dans ce contexte, SDN (Software Defined Network) a émergé dans les datacenters pour redéfinir la façon de penser les réseaux plus en adéquation avec le contexte virtualisé. Cette thèse reprend le SDN pour l’appliquer en périphérie de réseaux sur les points d’accès Wi-Fi virtuels que nous avons créés. Plus qu’un nouveau paradigme de communications réseaux, nous verrons que l’introduction des concepts NFV/SDN aux réseaux Wi-Fi permettra dans un avenir proche de rendre les réseaux Wi-Fi plus souples, plus ouverts et plus évolutifs
Virtualization was originally introduced in networks to reduce maintenance and deployment costs. It has experienced tremendous growth and reshaped the landscape of IT and ITC networks. Virtualization permits the sharing of physical resources for instantiating isolated virtual machines despite the fact that it is drawing its resources from the same physical hardware. More recently NFV (Network Functions Virtualization) appeared, it allows to virtualize entire classes of network functions node in blocks that can connect to create communication services. In this thesis we virtualize the access network nodes, namely Wi-Fi access points. The Wi-Fi became one of the hot-topic technology for mobile operators, it allows them to offload some of the customers’ data traffic via hotspots. The problem that arises in such a mechanism is the existing wireless standards, and mobile devices connection management software have not been developed for this purpose. The Hotspot2.0 standard was created to overcome this limitation, by making the Wi-Fi experience similar to the cellular in terms of roaming, transparency and security. We have in our work, applied the concept of NFV by virtualizing these brand new Wi-Fi access points. One of the problems that we faced is the high security required by such standard, including the provisioning of client credentials in public areas. In our thesis we propose an innovative architecture for the repatriation of these credentials through NFC terminals. These same terminals will be used for access points’ urbanization by allowing users to create their own Wi-Fi virtual access point on the fly. The last aspect of this thesis is related to the management of virtualized entities changing communication patterns of legacy networks. In this context, SDN (Software Defined Network) emerged in data centers to redefine the way we think about networks, and is designed for virtualized environments. In this thesis we brought SDN to the edge of the network in our Wi-Fi virtual access points. More than a new paradigm of networks communications, we will see that NFV/SDN in Wi-Fi networks will in the near future make Wi-Fi networks more flexible, open and scalable

The application of mobile commerce to healthcare—namely, m-health—appears to offer a way for healthcare delivery to revolutionize itself and simultaneously address the critical areas of access, quality, and value. Integral to such an approach is the need for a robust wireless model. We propose the Wi-INET (wireless Internet, intranet, extranet) model as the way to deliver m-health excellence.

During the past few years, several location systems have been proposed that use multiple technologies simultaneously in order to locate a user. One such system is described in this article. It relies on multiple sensor readings from Wi-Fi access points, IR beacons, RFID tags, and so forth to estimate the location of a user. This technique is known better as sensor information fusion, which aims to improve accuracy and precision by integrating heterogeneous sensor observations. The proposed location system uses a fusion engine that is based on dynamic Bayesian networks (DBNs), thus substantially improving the accuracy and precision.

The use of an innovative, intelligent control algorithm applied to the Siemens SGT-300 DLE engine is described. The algorithm ensures stable operation and minimises emissions over a wide variation in fuel composition. The Siemens 8MW class SGT-300 gas turbine has been in operation at the University of New Hampshire (USA) since 2006. As well as operating on natural gas or diesel, the engine also operates on a gas processed from a landfill. These gases have a variable Wobbe Index (WI) covering the range 29.7 to 49 MJ/m3. No modifications have been required to the standard DLE combustion hardware. Introduction of the intelligent control algorithm has been instrumental in achieving this tri-fuel capability. Accumulation of more than 10 000 hours running on non-standard fuel has been achieved. The intelligent control algorithm exploits knowledge of the stable operating window through continual modification of the fuel schedule to avoid both lean blow out and high metal temperatures. Operationally, this results in a reduction in the NOx emissions, through controlling the unmixedness, and higher engine reliability, through the response of the algorithm to flame stability. Combining these advantages the control algorithm can deliver reliable engine operation on variable composition fuels when using standard combustion hardware achieving single digit NOx emissions not only on natural gas but also on processed landfill gas. This paper describes the control algorithm and presents results of the development from high pressure combustion rig and engine development test to field operation with both natural gas and processed landfill gas.

It was shown platelet antiplasmin activity which is released by col 1anen(Col)and thrombin, probably associated with a-oran u 1 es . Lys i s area produced by eunl obul i ns (eun) of PPP and PRP whether or not previously treated with ADP(5uM), Col(20ug/ml) and aspirin(ASA)(00up/nl)in plas-mi nooen- f ree-f i bri n plates were s tudi ed. Res u 1 ts (mm2 ) were:eunPPP:151.3±39.8;+ADP:155.7±47;+Co1: 155.5±150.8; + ASA: 160±142. -EugPRP: 142*42;+ADP: 145*72;+Col : 136*43 ; -⋋ASA: 138+47.-EugPRP produced slightly lower lysis area than euaPPP(p:ns).ADP , Co 1 and ASA neither modify the lysis area of eugPPP nor of eugPRP.Washed piatelets(WP)whether or not treated with ASA were resuspended in eu^PPP and then treated with Co 1 ( 2 and 20ug/ml ). Resul ts (mm2 )were : euoPPP:109.8+35;+3xl05WP/ul:66.4±24;+106WP/u1:63±17;+2x lO WP/ul:58.4±13.- Wi th Col(20ug/ml):euoPPP:101.3±28; + 3xl05WP/ul:48.4±14; + 10cWP/ul :46.2±16;+2xl06WP/ul :44.5± i2;+ 2x106WP/u1+ ASA:45.2±8.-With Col(2ug/nl):eugPPP:10 3± 25;+2xl06WP/ul : 49±10 ;+2x1 Of>WP/ul+AS A: 50 . 9±13 . WP in eug PPPshowed lower lysis area than eugPPP(d<0.00 1). The higher number of piatelets ,the lower lysis area.Col-treated WP showed greater inhibition of lysis area than non-treated WP.ASA could not inhibit this effectConclusion:In euoPRP there was a slioht antiplasmin activity related with platelets not comoletely eliminated from eug fractionation.WP in euoPPP showed hioher antiplasmin activity.High and low doses of Col produced antiplasmin release.ASA could not inhibit its release with both doses of Col.We must consider the possibility that platelet antiplasmins could be released by different metabolic pathways other than cycl oox.ygenase way or they are not stored in the a-granules.