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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Beacone : En ny BLE beacon med Wi-Fi-stöd för uppdatering av URL / Beacone : A new BLE Beacon with Wi-Fi support for URL update

Fryxelius, Jonathan, Runeson, Johannes January 2017 (has links)
Ända sedan radion uppfanns har trådlös kommunikation varit ett mål för modern teknologi. Trots över 100 års teknologisk utveckling är radiosignaler högst relevanta, och används idag både för traditionell enkelriktad radiosändning, men också som grund för Bluetoothteknologin, som stöds av allt från bilar till telefoner och högtalare. Den här avhandlingen beskriver framtagandet av en speciell typ av Bluetoothsändare, så kallad beacon, som dessutom tillämpar trådlös nätverksanslutning för att utvidga beacons klassiska funktionalitet och ge nya möjligheter. Den nya produkten kallas Beacone. Som stöd för dess funktionalitet utvecklas ett webbgränssnitt och en mobilapplikation. Resultatet utvärderas och möjliga förbättringar diskuteras. Arbetet visar att det under flera omständigheter finns fördelar med en nätverksansluten beacon, som tillhandahåller möjligheter som inte annars hade funnits. / Ever since the invention of the radio, wireless communication has been the goal for modern technology. Despite 100 years of technological development, radio waves remain highly relevant, and are today used both in traditional one-way radio transmission, but also as the foundation for Bluetooth technology, which is supported by cars, phones, speakers, and everything in between. This report describes the development of a special Bluetooth transmitter, a so-called beacon, which also features wireless network connection to expand the traditional functionality of beacons and yield new opportunities. The new product is named Beacone. Supportive software, such as a web interface and a mobile cellphone application, is also developed. The result is evaluated, and possible improvements are discussed. The work shows that there are circumstances where Wi-Fi connectivity provides benefits which would not be available without it.
132

Modeling The Spread Malware In Computer Networks

reddy, patlolla pradeep, reddy, pasam raghava January 2009 (has links)
Our research is an exploratory study on how various parameters in the attack, ranging from that of the worm (replication rate), to those of the network (number of nodes, % fire-walled computers) as well as user behaviour (frequency of checking mail) impact the spread of malware. Through the development of a simulator we have created various experiments and have studied the impact of all possible parameters
133

Trådlös styrning av larmsystem : Kandidatuppsats

Green, Jonas, Delén, Johan January 2010 (has links)
Lansen Technology develops and sells alarm systems. The communication between the system devices are wireless. The radio protocol used by the system is developed by Lansen with the purpose to be energy efficient. The alarm systems target groups are individuals, businesses and government agencies. The current system is installed, configured and controlled from a control panel for all audiences. Some operations are also available using a mobile phone via a GSM network. Lansen Technology has a request to move more of the functionality to a mobile device and avoid the cost of using the GSM network used today. The target group for the application is primarily users that want instant access to information within the network. The project has mainly consisted of two parts. The first part of the project was to investigate two different wireless technologies that were relevant to the project. The investigation showed that Bluetooth was the best choice based on the requirements of the alarm system. Bluetooth was then integrated to the existing alarm system. The second part consisted of developing software to operate the alarm system from a PDA running Windows Mobile. An application was developed successfully and it can perform the majority of the functions specified by Lansen. The idea of remote controlling an alarm system from a mobile device has resulted in a successful project. Lansen Technology develops and sells alarm systems. The communication between the system devices are wireless. The radio protocol used by the system is developed by Lansen with the purpose to be energy efficient. The alarm systems target groups are individuals, businesses and government agencies. The current system is installed, configured and controlled from a control panel for all audiences. Some operations are also available using a mobile phone via a GSM network. Lansen Technology has a request to move more of the functionality to a mobile device and avoid the cost of using the GSM network used today. The target group for the application is primarily users that want instant access to information within the network. The project has mainly consisted of two parts. The first part of the project was to investigate two different wireless technologies that were relevant to the project. The investigation showed that Bluetooth was the best choice based on the requirements of the alarm system. Bluetooth was then integrated to the existing alarm system. The second part consisted of developing software to operate the alarm system from a PDA running Windows Mobile. An application was developed successfully and it can perform the majority of the functions specified by Lansen. The idea of remote controlling an alarm system from a mobile device has resulted in a successful project. / Lansen Technology utvecklar och säljer larmsystem. Kommunikationen mellan systemets enheter sker trådlöst. Det trådlösa radioprotokoll som används är utvecklat av Lansen med målet att vara energisnål. Larmsystemets målgrupp är privatpersoner, företag och myndigheter. Nuvarande system installeras, konfigureras och styrs från en manöverpanel. Viss manövrering kan också ske med hjälp av mobiltelefon via GSM-nätet. Önskemål från Lansen Technology finns att flytta funktionalitet till en mobil enhet och att komma ifrån trafikkostnaden på GSM-nätet. Målgruppen för applikationen är i första hand användare som omgående kräver tillgång till information från larmsystemet. Projektet har i huvudsak bestått av två delar. Första delen av projektet bestod av att utreda de två olika trådlösa tekniker som var aktuella för projektet. Utvärderingen visade att Bluetooth var det bästa valet med de krav larmsystemet ställde på uppkopplingen. Bluetooth integrerades därefter i nuvarande larmsystem. Den andra delen bestod av att utveckla en mjukvara  för att kunna manövrera larmsystemet från en handdator med Windows Mobile. Applikationen utvecklades framgångsrikt och kan utföra majoriteten av de funktioner som specificerats inför projektet. Idén med att fjärrstyra larmsystemet från en mobil enhet har resulterat i ett lyckosamt projekt. Lansen Technology utvecklar och säljer larmsystem. Kommunikationen mellan systemets enheter sker trådlöst. Det trådlösa radioprotokoll som används är utvecklat av Lansen med målet att vara energisnål. Larmsystemets målgrupp är privatpersoner, företag och myndigheter. Nuvarande system installeras, konfigureras och styrs från en manöverpanel. Viss manövrering kan också ske med hjälp av mobiltelefon via GSM-nätet. Önskemål från Lansen Technology finns att flytta funktionalitet till en mobil enhet och att komma ifrån trafikkostnaden på GSM-nätet. Målgruppen för applikationen är i första hand användare som omgående kräver tillgång till information från larmsystemet. Projektet har i huvudsak bestått av två delar. Första delen av projektet bestod av att utreda de två olika trådlösa tekniker som var aktuella för projektet. Utvärderingen visade att Bluetooth var det bästa valet med de krav larmsystemet ställde på uppkopplingen. Bluetooth integrerades därefter i nuvarande larmsystem. Den andra delen bestod av att utveckla en mjukvara  för att kunna manövrera larmsystemet från en handdator med Windows Mobile. Applikationen utvecklades framgångsrikt och kan utföra majoriteten av de funktioner som specificerats inför projektet. Idén med att fjärrstyra larmsystemet från en mobil enhet har resulterat i ett lyckosamt projekt.
134

Kartbaserad inomhuspositionering med virtuella accesspunkter / Map-aided indoor positioning using virtual access points

Lagerhult, Christopher January 2014 (has links)
Det har gjorts mycket forskning kring Positioneringssystem för inomhusbruk då många applikationer och tjänster ärberoende eller kan förbättras av det. Trots detta finns idag ingen standard för hur positionering inomhus ska fungera.För de flesta utomhusmiljöer kan en modern mobiltelefons position erhållas med ett par meters precision via GPS. I eninomhusmiljö sjunker signalen drastiskt och en precis position är svår att uppskatta. En väl etablerad teknik är Wi-Fioch kan med fördel användas då de flesta inomhusmiljöer idag redan har Wi-Fi accesspunkter installerade. Då enmottagare erhåller en signal från en accesspunkt kan distansen dem emellan uppskattas för att sedan uppskattapositionen med den matematiska tillämpningen trilateration. Då de flesta idag äger en mobiltelefon kan mobilen ageramottagare och tekniken kan således vara tillgänglig för alla.Bidraget med examensarbetet är en undersökning av den effekt virtuella accesspunkter har på ett positioneringssystemdär en trilaterationsbaserad lösning använts på Wi-Fi-signaler över både 2.4Ghz samt 5Ghz bandet i kombination med ett partikelfilter. Vidare kommer en karta nyttjas i ett försök att öka precisionen genom att skapa restriktioner för hurpositioneringen får röra sig. Resultatet visade att nyttjandet av virtuella accesspunkter ökade precisionen med drygt 10 procent och den valda kartlösningen med nästan 20 procent. / A lot of research has been made regarding indoor positioning since many applications and services are dependent or canbe improved by it. Despite this, no standard has been set for indoor positioning system concerning the best approach. Inoutdoor environments most modern smart phones can be used to estimate their position using the GPS. Indoors this isnot the case since the received signal strength is decreased drastically. A well-established technique is however Wi-Fiwhich promotes the use of it. When a receiver acquires a signal from a Wi-Fi access point the distance between them canbe estimated. Three or more known distances enables the receiver to calculate its position using a mathematicalapproach called trilateration. With the smart phone acting as the receiver, the approach is enabled for everyone.The contribution of this thesis is an investigation of the effect of using virtual access points. This will be tested in atrilateration based positioning system using both the 2.4Ghz and 5Ghz frequency band in combination with a particlefilter. In an attempt to increase the precision a map will be added into the algorithm with the intention of restricting usermovements. The attained result shows that the use of virtual access points decreased the position estimation error by approximately 10 percent, and the implemented map solution by merely 20 percent.
135

An integrated approach to the analysis of environmental factors that influence male reproductive health

Adams, Jessica Alice January 2016 (has links)
At least 30 million men are infertile around the world, identifying male factor infertility as a global health issue. In the past 70 years, evidence of a significant general decline in sperm quality has been reported, prompting concerns about the implications for reproductive health. Over the same period, there have been substantial changes in human lifestyles. New technologies, such as mobile phones and wi-fi, have been proposed to have a negative impact on a range of health outcomes, from an increased risk of cancer to a decrease in fertility. However, these links remain controversial. Over the last 30 years, the introduction of assisted reproductive technologies (ART) has offered infertile patients, particularly men with severe male factor infertility, a successful treatment option. However, miscarriage rates associated with fertility treatment can be as high as 30% and how this risk had changed over time was unclear. In addition, there are natural fluctuations in human health, including seasonal changes to birth rates. However, the clinical implications of these fluctuations need to be established. In this thesis, using an integrated approach that combined epidemiological research with laboratory investigations, I show that sperm quality is negatively affected by exposure to RF-EMR from mobile phones and wi-fi. I also identified a seasonal summer increase in sperm motility and morphology that followed patterns of seasonality in birth rates and in the success of assisted conception cycles. I showed that although the number of successful conceptions from ART has increased over time, there has been an equal increase in miscarriage rates. Male reproductive health continues to be under-researched when compared with the female, this inequality needs to be addressed in order to understand the causes of the decline in male fertility and the relationship this has with subsequent reproductive success.
136

Radiobaserad spårning av rörlig utrustning inomhus

Davodi, Rashed, Högberg, Jonatan January 2017 (has links)
No description available.
137

Positional Quality of Service using Dynamic Collection Fingerprinting

Grönlund, Fredrik January 2017 (has links)
Positioning in environments where GPS is absent is a field currently under intensive research.Systems are currently being researched or designed for indoor use, often relying on ultra-wideband radio, ultrasound, fingerprinting or Wi-Fi.For underground mining, the problem is magnified, as installation of new equipment is expensive.Mobilaris Mining and Civil Engineering AB supplies a service, Mobilaris Mining Intelligence, using existing Wi-Fi infrastructure present in many mines for communication, and has developed two Wi-Fi-based positioning methods and one hybrid system, using dead reckoning and gyroscope.The first positioning method, Positioning Method 1, positions resources at the location of the strongest access point.The other positioning method, Positioning Method 4, uses signal strength values to construct an area where the tag is likely to be, similar to a Venn diagram. This thesis proposes a Quality of Positioning system to dynamically and select the best of all available positioning systems for every object to be positioned.This should be trained automatically by ``light vehicles'', such as service pickup trucks, equipped with the hybrid positioning system acting as reference values.Testing was done at the Kristineberg Mine in Västerbotten, Sweden, using a pickup truck equipped with the hybrid positioning system and Wi-Fi personnel positioning tags.It was found that the difference between the two positioning methods was not statistically significant, and that the hybrid positioning system was insufficiently accurate to act as a reference value. This thesis further revealed that the architecture of Mobilaris Mining Intelligence makes implementing a dynamic system impractical.Although planned for, the dynamic Quality of Positioning system was not implemented due to being deemed too impractical, complex and time-consuming compared to the benefit it would have provided.A high-level description of such an implementation is however presented, should it be motivated by future studies.
138

Real-time, Location-based Hand Hygiene Monitoring and Notification System

Baslyman, Malak January 2014 (has links)
Rising infection rates in healthcare is a global issue that causes complications for the patient, extended hospital stay, financial difficulties, and even death. One of the crucial factors that reduce those infections is better hand hygiene. Due to the lack of automated systems that can help monitoring hand hygiene compliance and reporting on collected data, some hospitals use direct observations, surveys, dispensers usage measurements and other such methods to monitor the compliance of care providers. This thesis proposes an alternative system that takes advantage of emerging off-the-shelf infrastructures in hospitals, and in particular of Real-Time Location Systems (RTLS) and intelligent hand sanitizer dispensers. Our RTLS-based system improves upon the current methods by enabling interactions with care providers through notifications when they do not execute expected hand hygiene actions during care processes, even for fine-grained location situations and by introducing the concept of intelligent dispensers. RHMNS (RTLS-based Hand Hygiene Monitoring and Notification System) has two approaches (time-based and activation-based) that are sharing the same structure but they are different in their way of deciding on taken or missed hand hygiene opportunities. RHMNS also provides informative reports about hand hygiene compliance and trends.
139

Smartphone Based Indoor Positioning Using Wi-Fi Round Trip Time and IMU Sensors / Smartphone-baserad inomhuspositionering med Wi-Fi Round-Trip Time och IMU-sensorer

Aaro, Gustav January 2020 (has links)
While GPS long has been an industry standard for localization of an entity or person anywhere in the world, it loses much of its accuracy and value when used indoors. To enable services such as indoor navigation, other methods must be used. A new standard of the Wi-Fi protocol, IEEE 802.11mc (Wi-Fi RTT), enables distance estimation between the transmitter and the receiver based on the Round-Trip Time (RTT) delay of the signal. Using these distance estimations and the known locations of the transmitting Access Points (APs), an estimation of the receiver’s location can be determined. In this thesis, a smartphone Wi-Fi RTT based Indoor Positioning System (IPS) is presented using an Unscented Kalman Filter (UKF). The UKF using only RTT based distance estimations as input, is established as a baseline implementation. Two extensions are then presented to improve the positioning performance; 1) a dead reckoning algorithm using smartphone sensors part of the Inertial Measurement Unit (IMU) as an additional input to the UKF, and 2) a method to detect and adjust distance measurements that have been made in Non-Line-of-Sight (NLoS) conditions. The implemented IPS is evaluated in an office environment in both favorable situations (plenty of Line-of-Sight conditions) and sub-optimal situations (dominant NLoS conditions). Using both extensions, meter level accuracy is achieved in both cases as well as a 90th percentile error of less than 2 meters.
140

Estimation of Tourist Travel Patterns with Recursive Logit Models based on Wi-Fi Data with Kyoto City Case Study / Wi-Fiデータを用いた再帰的ロジットモデルによる観光行動パターンの推定に関する研究-京都市を例として-

Gao, Yuhan 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23178号 / 工博第4822号 / 新制||工||1753(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 山田 忠史, 教授 藤井 聡, 准教授 SCHMOECKER Jan-Dirk / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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