In modern life, there are many applications where positioning plays an important role. People have developed the global positioning system (GPS) to locate world wide position with error in decameter scales, which brings people much convenience. However, the accuracy of GPS is too low for indoor localization. The signals will drop down due to the signal attenuation caused by construction materials. With the well-developed GPS being indispensable for outdoor activities, many researchers have been also devoted to seeking an indoor positioning system to realize indoor localization with acceptable error. Indoor localization can be very useful in different situations, like locating, tracking, navigation and identification. For example, in the mall, locating the exact goods for customers can provide much convenience and benefits. Locating and tracking in the airport can greatly help passengers save their time and energy in reaching the destination. In another general scenario of identification, the population of observed targets is usually larger than just one. Hence, only with small error, indoor localization system (ILS) can be able to identify the targets despite the neighbors. Due to the emerging and urging demands of increasing the accuracy of indoor localization, we propose a novel design of three dimensional (3-D). optical receiver for visible light communication (VLC) indoor positioning system. First, we model the optical wireless channel. Then we utilize modified triangulation method to obtain more robust receiver position by using at least two light-emitting diodes (LEDs) and one receiver consisting of nine photodetectors (PDs). Finally, the improved algorithm is implemented and the results are shown under our three dimensional multiple photodetectors (multi-PDs) structure receiver. In the simulation, we take the parameters of Lambertian radiation pattern, LEDs and PDs as those shown in [1] . To be noticed, our design of multi-PDs receiver is fully expanded into three dimensions compared with the pyramid receiver (PR), which allows indoor positioning with our receiver structure to be more robust to the higher or corner positions. The details will be explained in the following sections. Based on Multiple-Photodiodebased Indoor Positioning algorithm [1], the indoor positioning algorithm is improved by redefining the optimization problem of obtaining the direction from receiver to LED and using weighted triangulation method to locate receiver position. We admit the solution under the redefined problem is not optimal to the actual problem. Yet, our given solution is better to that in [1] due to the existence of noise, which is reasonable and has been verified.

RSS šaltinių kaupimo ir peržiūros sistema sukurta, norint įgyvendinti funkcijas, kurių nėra kitose panašiose sistemose: naujienų siuntimas el. paštu, automatinis naujienų archyvavimas. Kita priežastis, dėl ko sukurta sistema, tai vartotojo sąsajos paprastumas, nereikalaujantis specifinių žinių, kad nekiltų keblumų naudojantis sistemos funkcijomis. Pirmame darbo skyriuje aprašoma HTML, XML, RSS ir Atom standartai, detalizuoti paveiksliukais ir lentelėmis. Taip pat aprašoma RSS apdorojimo web sprendimai, trumpai aprašomi privalumai, trūkumai ir pateikiama palyginimų lentelė. Reikalavimų specifikacija parodo, kokias funkcijas turi atlikti sistema. Pateikiama panaudojimo atvejų diagrama, funkciniai ir nefunkciniai reikalavimai. Taip pat aprašomi reikalavimai esamų duomenų perkėlimui ir galimos sistemos kūrimo rizikos. Trečiame skyriuje, architektūros specifikacija pateikama UML diagramomis: veiklos, sekų, bendradarbiavimo, klasių, esybių ryšių ir komponentų diagramos. Iš pateiktų diagramų galima matyti kaip sistema atrodo iš architektūros pusės ir galima suprasti kaip veikia viena ar kita funkcija. Testavimo dokumentacijos paskirtis – parodyti dar neatrastas klaidas, kurios gali paveikti visos sistemos funkcionalumą. Sistemos testavimas pateikiamas lentelėse. Buvo atlikti sistemos funkcijų, našumo, suderinamumo ir saugumo testavimai. Vartotojo vadovas sukurtas, kad parodyti sistemos funkcijų galimybes. Vartotojo vadovas pateikiamas DUK formoje, integruota pačioje sistemos... [toliau žr. visą tekstą] / The "Gathering and Viewing System of RSS Sources" was developed in order to implement features that are not presented in other similar systems: send email newsletter to users and automatically archive news items. Another reason for creating a system is the simplicity of the user interface and does not require specific knowledge that avoid problems using the system. The first chapter describes the HTML, XML, RSS and Atom standards, detailed with pictures and tables. It also provides web solutions for processing RSS feeds, briefly describes the advantages and disadvantages. As a result, web solutions of the RSS feeds represents in comparison table. Requirements specification indicates what functions have to perform this system. It represents use case diagram, the functional and non-functional requirements. It also, describes the requirements of the existing data transfer and the potential risk of system development. In the third chapter of architectural specification contains UML diagrams: activity, sequence, collaboration, class, entity and component. From these diagrams you can see how the system looks like from the architecture side, this way you can understand the operation of one or the other function. Also, diagrams are represented in simple and short descriptions, and detailed tables. The purpose of testing documentation is to show undetected bugs that may affect the overall system’s functionality. The testing of system was detailed in tables. It was carried out of... [to full text]

yes / In this paper a comparison between two indoor localization algorithms using received signal strength is utilized the vector algorithm and the Comparative Received Signal Strength algorithm. The comparison considered the effect of the radio map resolution, the number of access points, and the operating frequency on the accuracy of the localization process. The experiments were carried out using ray tracing software, measured values and MATLAB.

Žiniatinklio srautų technologija neseniai pradėjo augti, tačiau ji sparčiai išplito ir tapo dažnai sutinkama internetiniuose puslapiuose. Dabar yra trys pagrindiniai naudojimi žiniatinklio srauto formatai ATOM 1.0, RSS 2.0 ir RSS 1.0. Šiame darbe yra parašyta nauja žiniatinklio srautų specifikacija, kuri sujungia visus ATOM 1.0, RSS 2.0 ir RSS 1.0 formatus ir pridedami atitinkamai nauji elementai. Kad tai padaryti buvi išanalizuota ATOM 1.0, RSS 2.0 ir RSS 1.0 formatų architektūra. Universalaus žiniatinklio srautų architektūra realizuota sukurtame konvertavimo į universalų žiniatinklio srauto metode, kuris gali būti naudojamas projektuose. Sukurtas metodas verčia ATOM 1.0, RSS 2.0 ir RSS 1.0 formatų dokumentus į šiame darbe aprašytą universalų žiniatinklio srauto formatą ir normalizuoja jį. Rezultatai, gauti po ATOM 1.0, RSS 2.0 ir RSS 1.0 dokumentų konvertavimo į universalų žiniatinklio srauto formatą yra palyginti ir padarytos išvados. / Feed technology has only just started growing, but it become very popular and can meet in most web pages. There is at least three major competing feed formats in ATOM 1.0, RSS 2.0 and RSS 1.0 . In this work is written new feed format specification, which joins all ATOM 1.0, RSS 2.0 and RSS 1.0 formats and includes new ones elements. To do this has been analysed ATOM 1.0, RSS 2.0 and RSS 1.0 architekture. Universal feed architekture realized in created universal feed parser method, which can be included in projects. Craeted method replaces ATOM 1.0, RSS 2.0 and RSS 1.0 documents into universal feed document and normalize them. Results got after converting ATOM 1.0, RSS 2.0 and RSS 1.0 feeds into universal feed document is compared and made conclusion.

Mémoire de recherche diplôme de conservateur des bibliothèques : Bibliothéconomie : Villeurbanne, ENSSIB : 2005. / Texte intégral.

The use of autonomous UAV’s is a progressively expanding industry. This thesisfocuses on the landing procedure with the main goal to be independent of visualaids. That means that the landing site can be hidden from the air, the landingcan be done in bad weather conditions and in the dark. In this thesis the use ofradio signals is investigated as an alternative to the visual sensor based systems.A localization system is needed to perform the landing without knowing wherethe landing site is. In this thesis an Extended Kalman Filter (EKF) is derived andused for the localization, based on the received signal strength from a radio beaconat the landing site. There are two main goals that are included in the landing,to land as accurate and as fast as possible. To combine these two goals a simultaneoustrajectory optimization and target estimation problem is set up that can bepartially solved while flying. The optimal solution to this problem produces thepath that the UAV will travel to get the best target localization while still reachingthe target. It is shown that trying to move directly towards the estimated landingsite is not the best strategy. Instead, the optimal trajectory is a spiral that jointlyoptimizes the information from the sensors and minimizes the arrival time.

Location estimation when deployed on wireless networks supports a range of services including user tracking and monitoring, health care support and push and pull marketing. The main subject of this thesis is improving indoor and outdoor location estimation accuracy using received signal strength (RSS) from neighbouring base stations (BSs) or access points (APs), without using the global positioning system (GPS) or triangulation methods. For the outdoor environment, state-of-the-art deterministic and probabilistic algorithms are adapted to exploit principal components (PCs) and clustering. The accuracy is compared with K-nearest neighbour (KNN) algorithms using different partitioning models. The proposed scheme clusters the RSS tuples based on deviations from an estimated RSS attenuation model and then transforms the raw RSS in each cluster into new uncorrelated dimensions, using PCs. As well as simple global dimensionality reduction using PCs, the data reduction and rotation within each cluster improves estimation accuracy because a) each cluster can model the different local RSS distributions and b) it efficiently preserves the RSS correlations that are observed (some of which are substantial) in local regions and which independence approximations ignore. Different simulated and real environments are used for the comparisons. Experimental results show that positioning accuracy is significantly improved and fewer training samples are needed compared with traditional methods. Furthermore, a technique to adjust RSS data so that radio maps collected in different environmental conditions can be used together to enhance accuracy is also demonstrated. Additionally, in the radio coverage domain, a non-parametric probability approach is used for the radio reliability estimation and a semi-supervised learning model is proposed for the monitoring model training and evolution according to real-time mobile users’ RSS feedback. For the indoor environment, an approach for a large multi-story indoor location estimaiii tion using clustering and rank order matching is described. The accuracies using WiFi RSS alone, cellular GSM RSS alone and integrated WiFi and GSM RSS are presented. The methods were tested on real indoor environments. A hierarchical clustering method is used to partition the RSS space, where a cluster is defined as a set of mobile users who share exactly the same strongest RSS ranking set of transmitters. The experimental results show that while integrating of WiFi RSS with GSM RSS creates a marginal improvement, the GSM data can be used to ameliorate the loss of accuracy when APs fail.

The major problems encountered in wireless location are the effects caused by non-line of sight (NLOS) propagation and multipath interference. In the thesis, we propose an approach to mitigate NLOS error. First of all, we use improved biased Kalman filter (IBKF) based on time of arrival (TOA) measurement to identify and mitigate NLOS error. Applying the statistic characteristic that the standard deviation of the NLOS propagation errors is generally much larger than that of measurement noises in the LOS condition, we combine hypothesis test and sliding window to identify NLOS error. According to the feedback identification and the calculated standard deviation, IBKF switches biased or unbiased to process TOA measurement. Nevertheless, the performance of IBKF-TOA is still affected slightly by NLOS error. Since extended Kalman filter (EKF) based on received signal strength (RSS) measurement is designed for prespecified environments, the effect of NLOS mitigation is more obvious. Moreover, EKF-RSS not only exists higher error probability in NLOS identification, but also needs longer time to converge in the cases that start with NLOS. Comparing IBKF-TOA with EKF-RSS, we adopt interacting multiple model (IMM) in the proposed data fusion structure for processing TOA and RSS measurements. In the proposed scheme, we reserve the basic IMM structure and add the step of NLOS identification into basic IMM structure. By accurate NLOS identification results and soft decision of IMM, the proposed scheme will switch to adequate filter mode and obtain better estimation. With simulation in UWB channel, the analysis and performance evaluation show advantages and disadvantages of using IBKF-TOA, EKF-RSS, and proposed scheme. Simulation results reveal that NLOS error can be mitigated effectively by data fusion of TOA and RSS measurements and can achieve high accuracy in positioning and tracking.

The demand of Indoor Location Based Services LBS has increased over the past years as smart phone market expands. As a result, there's a growing interest in developing efficient and reliable indoor positioning systems for mobile devices. Wi-Fi signal strength fingerprint-based approaches attract more and more attention due to the wide deployment of Wi-Fi access points. Indoor positioning problem using Wi-Fi signal fingerprints can be viewed as a machine learning task to be solved mathematically. This thesis proposes an efficient and reliable Wi-Fi real-time indoor positioning system using machine learning algorithms. The proposed positioning system, together with a location server equipped with the same algorithms, are tested and evaluated in several indoor scenarios. Simulation and testing results show that the proposed system is a feasible LBS solution.

The demand of Indoor Location Based Services LBS has increased over the past years as smart phone market expands. As a result, there's a growing interest in developing efficient and reliable indoor positioning systems for mobile devices. Wi-Fi signal strength fingerprint-based approaches attract more and more attention due to the wide deployment of Wi-Fi access points. Indoor positioning problem using Wi-Fi signal fingerprints can be viewed as a machine learning task to be solved mathematically. This thesis proposes an efficient and reliable Wi-Fi real-time indoor positioning system using machine learning algorithms. The proposed positioning system, together with a location server equipped with the same algorithms, are tested and evaluated in several indoor scenarios. Simulation and testing results show that the proposed system is a feasible LBS solution.