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U ovom radu definirano je bežično upravljanje zajedno s Bluetooth tehnologijom, s fokusom na Bluetooth Low Energy (BLE) protokolu. Ukratko su objašnjeni ugradbeni sustavi, s naglaskom na Nucleo STM32WB55 pločicu i mikrokontroler STM32WB55. Također je detaljno je opisan razvoj aplikacije za bežično upravljanje ugradbenim generatorom signala temeljen na spomenutom mikrokontroleru te su prikazni rezultati i za kraj, izveden zaključak. This thesis presents an overview of wireless control, focusing on Bluetooth technology, particularly the Bluetooth Low Energy (BLE) protocol. It briefly explains embedded systems, with an emphasis on the Nucleo STM32WB55 board and the STM32WB55 microcontroller. Additionally, it provides a detailed description of the development of an application for wireless control of an embedded signal generator based on the mentioned microcontroller. The results are presented, and the thesis concludes with a summary.

User location is becoming an increasingly common and important feature for a wide range of services. Smartphone owners increasingly use location-based services, as service providers add context-enhanced functionality such as car-driving routes, COVID-19 tracking, crowdedness indicators, and suggestions for nearby points of interest. However, positioning a user indoors is still problematic due to the fading of the radio signal caused by multipath and shadowing, where both have complex dependencies on the indoor environment. Location fingerprinting is a common positioning method where Radio Signal Strength (RSS) measurements are compared to a reference database of previously stored RSS values. Due to the size of the reference databases, these are often stored in the cloud. However, server-side positioning computations make preserving the user’s privacy problematic. Given the assumption that a user does not want to communicate his/her location, we pose the question of whether a passive system with client-side computations can substitute fingerprinting-based systems, which commonly use active communication with a server. We compared two passive indoor location systems based on multilateration and sensor fusion using an Unscented Kalman Filter (UKF) with fingerprinting and show how these may provide accurate indoor positioning without compromising the user’s privacy in a busy office environment.

Location privacy poses a critical challenge as the use of mobile devices and location-based services becomes more and more widespread. Proximity-detection data can reveal sensitive information about individuals, making it essential to preserve their location data. One way to achieve privacy protection is by adding noise to ground-truth data, which can introduce uncertainty while still allowing moderate utility for proximity-detection services and Received Signal Strength (RSS)-based localization. However, it is important to carefully adjust the amount of noise added in order to balance the privacy and accuracy concerns. This paper expands our previous work on evaluating location privacy bounds based on measurement error and intentionally added noise. Our model builds upon existing work in differential privacy and introduces other techniques to estimate privacy bounds specific to proximity data. By using real-world measurement data, we measure the privacy-accuracy trade-off and suggest cases where additional noise could be added. Our framework can be utilized to inform privacy-preserving location-based applications and guide the selection of appropriate noise levels in order to achieve the desired privacy-accuracy balance.

Wearable devices are starting to gain popularity, which means that a large portion of the population is starting to acquire these products. This kind of technology comes with a lot of advantages, as it simplifies different tasks people do daily. However, as they recollect sensitive data, they are starting to be targets for cybercriminals. The number of attacks on wearable devices forces manufacturers to improve the security of these devices to protect them. Many vulnerabilities have appeared in communication protocols, specifically Bluetooth. We focus on understanding the Bluetooth protocol and what countermeasures have been applied during their updated versions to solve the most common security problems. We have performed a passive attack on six different smartwatches to discover their vulnerabilities during the pairing process. Furthermore, we have developed a proposal of requirements needed for maximum security of wearable devices, as well as the minimum requirements needed to have a secure pairing process between two devices via Bluetooth.

Energy efficiency is one of the key aspects in energy transition, especially in building construction. One of the important things is also thermal comfort of the individuals. In this article, the design and the first results for the novel sensor device used to measure skin temperature are presented at two points used for purposes of estimating thermal comfort, a subjective feeling expressing the satisfaction with the thermal environment.

Efficiently managing coexistence is crucial for achieving high-quality wireless communication in the Industrial, Scientific, and Medical (ISM) band where multiple wireless communication systems operate. Coexistence problems between Wi-Fi and Bluetooth Low Energy (BLE) signals are especially significant due to their shared frequency band, which often leads to interference and a reduced performance for both systems. Therefore, effective coexistence management strategies are essential for ensuring the optimal performance of Wi-Fi and Bluetooth signals in the ISM band. In this paper, the authors conducted a study to investigate coexistence management in the ISM band by evaluating four frequency hopping techniques: random, chaotic, adaptive, and an optimized chaotic technique proposed by the authors. The optimized chaotic technique aimed to minimize interference and ensure zero self-interference among hopping BLE nodes by optimizing the update coefficient. Simulations were conducted in an environment with existing Wi-Fi signal interference and interfering Bluetooth nodes. The authors compared several performance metrics, including the total interference rate, total successful connection rate, and trial execution time for channel selection processing time. The results indicated that the proposed optimized chaotic frequency hopping technique achieved a better balance between reducing interference with Wi-Fi signals, achieving a high success rate for connecting BLE nodes, and requiring minimal trial execution time. This makes it a suitable technique for managing interference in wireless communication systems. While the proposed technique had a higher interference than the adaptive technique for small numbers of BLE nodes, for larger numbers of nodes it had a much lower interference than the adaptive technique. The proposed optimized chaotic frequency hopping technique provides a promising solution for effectively managing coexistence in the ISM band, particularly between Wi-Fi and BLE signals. It has the potential to improve the performance and quality of wireless communication systems.

International audience; The ubiquity of mobile devices equipped with radio communication technologies has made large-scale data collection on human mobility commonplace [SSGL15]. Therefore, with the lack of datasets, data collection and publication are raising new scientific questions. In this paper, we present the PILOT dataset and its privacy-preserving data collection methodology for wireless communication technologies. The dataset is a collection of four pieces of information collected together in different mobility contexts. It includes three wireless communication technologies: WiFi beacons, Bluetooth Low Energy (BLE) beacons and Long Range Radio (LoRa) packets, as well as additional information that includes: Acceleration, Roll and Pitch, all collected at the same time. We provide the keys to replicate this data collection. The dataset is collected for about 60 hours, with a size of 150 MB using Pycom's FiPy devices and is uploaded to GitHub. We believe that the combination of the different types of information collected in different mobility scenarios constitutes a new generation of a rich dataset.; L'omniprésence des appareils mobiles équipés de technologies de communication radio a rendu courante la collecte de données à grande échelle sur la mobilité humaine [SSGL15]. Par conséquent, avec le manque d'ensembles de données, la collecte et la publication de données s'avèrent lever de nouvelles questions scientifiques. Dans cet article, nous présentons l'ensemble de données PILOT et sa méthodologie de collecte de données préservant la confidentialité des technologies de communication sans fil. L'ensemble de données est une collection de quatre éléments d'information collectés conjointement dans différents contextes de mobilité. Il comprend trois technologies de communication sans fil : balises WiFi, balises BLE (Bluetooth Low Energy) et paquets LoRa (Long Range Radio), ainsi que des informations supplémentaires qui comprennent : Accélération, Roulis et Tangage, toutes collectées en même temps. Nous fournissons les clés pour reproduire cette collecte de données. Le jeu de données est collecté pendant environ 60 heures, avec une taille de 150 Mo en utilisant les dispositifs FiPy de Pycom et il est téléchargé sur GitHub. Nous pensons que la combinaison des différents types d'informations collectées dans différents scénarios de mobilité constitue une nouvelle génération d'un riche ensemble de données.

In late 2019, a new genre of coronavirus (COVID-19) was first identified in humans in Wuhan, China. In addition to this, COVID-19 spreads through droplets, so quarantine is necessary to halt the spread and to recover physically. This modern urgency creates a critical challenge for the latest technologies to detect and monitor potential patients of this new disease. In this vein, the Internet of Things (IoT) contributes to solving such problems. This paper proposed a wearable device that utilizes real-time monitoring to detect body temperature and ambient conditions. Moreover, the system automatically alerts the concerned person using this device. The alert is transmitted when the body exceeds the allowed temperature threshold. To achieve this, we developed an algorithm that detects physical exercise named “Continuous Displacement Algorithm” based on an accelerometer to see whether a potential temperature rise can be attributed to physical activity. The people responsible for the person in quarantine can then connect via nRF Connect or a similar central application to acquire an accurate picture of the person’s condition. This experiment included an Arduino Nano BLE 33 Sense which contains several other sensors like a 9-axis IMU, several types of temperature, and ambient and other sensors equipped. This device successfully managed to measure wrist temperature at all states, ranging from 32 °C initially to 39 °C, providing better battery autonomy than other similar devices, lasting over 12 h, with fast charging capabilities (500 mA), and utilizing the BLE 5.0 protocol for data wireless data transmission and low power consumption. Furthermore, a 1D Convolutional Neural Network (CNN) was employed to classify whether the user is feverish while considering the physical activity status. The results obtained from the 1D CNN illustrated the manner in which it can be leveraged to acquire insight regarding the health of the users in the setting of the COVID-19 pandemic.

As a response to the global COVID-19 surge in 2020, many countries have implemented lockdown or stay-at-home policies. If, however, the contact persons of every infected patient could be identified, the number of virus transmissions could be reduced, while the more incisive measures could be softened. For this purpose, contact tracing using smartphones is being considered as a promising technique. Here, smartphones emit and scan for Bluetooth Low Energy (BLE) signals for detecting devices in range. When a device is detected, its distance is estimated by evaluating its received signal strength. The main insight that is exploited for distance estimation is that the attenuation of a signal increases with the distance along which it has traveled. However, besides distance, there are multiple additional factors that impact the attenuation and hence disturb distance estimation. Among them, frequency-selective hardware and signal propagation belong to the most significant ones. For example, a BLE device transmits beacons on three different frequencies (channels), while the transmit power and the receiver sensitivity depend on the frequency. As a result, the received signal strength varies for each channel, even when the distance remains constant. However, the information on which wireless channel a beacon has been received is not made available to a smartphone. Hence, this error cannot be compensated, e.g., by calibration. In this paper, we for the first time provide a solution to detect the wireless channel on which a packet has been received on a smartphone. We experimentally evaluate our proposed technique on multiple different smartphone models. Our results help to make contact tracing more robust by improving the accuracy of distance estimation.

Bluetooth low energy (BLE)-based location service technology has become one of the fastest growing applications for Bluetooth. Received signal strength (RSS) is often used in localization techniques for ranging or location fingerprinting. However, RSS-based localization solutions have poor performance in multipath environments. In this paper, we present a measurement system designed using multiple ESP32 BLE modules and the Bluetooth mesh networking technology, which is capable of exploiting the space, time, and frequency diversities in measurements. To enable channel-aware multi-device RSS measurements, we also designed a communication protocol to associate channel ID information to advertising messages. Based on channel measurement and analysis, we demonstrate that with a six-receiver configuration and space-time-frequency diversity combining, we can significantly reduce the residual linear regression fitting errors in path loss models. Such a reduction leads to more accurately correlating RSS measurements to the distance between the transmitter and receiver devices and thus to achieving improved performance with the RSS-based localization techniques. More importantly, the reduction in the fitting errors is achieved without differentiating the three advertising channels, making it possible to conveniently implement the proposed six-receiver configuration using commercially available BLE devices and the standard Bluetooth mesh networking protocol stack.

Passive Human Sensing (PHS) is an approach to collecting data on human presence, motion or activities that does not require the sensed human to carry devices or participate actively in the sensing process. In the literature, PHS is generally performed by exploiting the Channel State Information variations of dedicated WiFi, affected by human bodies obstructing the WiFi signal propagation path. However, the adoption of WiFi for PHS has some drawbacks, related to power consumption, large-scale deployment costs and interference with other networks in nearby areas. Bluetooth technology and, in particular, its low-energy version Bluetooth Low Energy (BLE), represents a valid candidate solution to the drawbacks of WiFi, thanks to its Adaptive Frequency Hopping (AFH) mechanism. This work proposes the application of a Deep Convolutional Neural Network (DNN) to improve the analysis and classification of the BLE signal deformations for PHS using commercial standard BLE devices. The proposed approach was applied to reliably detect the presence of human occupants in a large and articulated room with only a few transmitters and receivers and in conditions where the occupants do not directly occlude the Line of Sight between transmitters and receivers. This paper shows that the proposed approach significantly outperforms the most accurate technique found in the literature when applied to the same experimental data.

Smart cities and smart mobility necessitate the development of newly adapted approaches and applications that ensure data connection among their particular parts; thus, the complex systems of smart technologies can be applied. Especially in the field of transport, mobility, and smart solutions, many of these applications require precise localization. Global navigation satellite system (GNSS) localization is used mainly because of its availability, reliability, and sufficient precision. However, there are also blind spots in smart cities where the GNSS is not available, e.g., in tunnels. This article presents an approach to fixing the issue of localization in road tunnels based on telecommunications with Bluetooth low energy (BLE) based infrastructure equipment. This approach enables us to ensure sufficient data resources for localization, and thus, smart applications can also be applied in the tunnels. At the same time, this approach also allows the fulfillment of individual needs according to the specifications of each tunnel or smart application. The outputs from testing and measurements are presented and discussed.

COVID-19 is highly contagious and spreads rapidly; it can be transmitted through coughing or contact with virus-contaminated hands, surfaces, or objects. The virus spreads faster indoors and in crowded places; therefore, there is a huge demand for contact tracing applications in indoor environments, such as hospitals and offices, in order to measure personnel proximity while placing as little load on them as possible. Contact tracing is a vital step in controlling and restricting pandemic spread; however, traditional contact tracing is time-consuming, exhausting, and ineffective. As a result, more research and application of smart digital contact tracing is necessary. As the Internet of Things (IoT) and wearable sensor device studies have grown in popularity, this work has been based on the practicality and successful implementation of Bluetooth low energy (BLE) and radio frequency identification (RFID) IoT based wireless systems for achieving contact tracing. Our study presents autonomous, low-cost, long-battery-life wireless sensing systems for contact tracing applications in hospital/office environments; these systems are developed with off-the-shelf components and do not rely on end user participation in order to prevent any inconvenience. Performance evaluation of the two implemented systems is carried out under various real practical settings and scenarios; these two implemented centralised IoT contact tracing devices were tested and compared demonstrating their efficiency results.

Marché passé entre l’abbé de Morimond et Jacques fort Claude boulon et Jean Rouier de Lénizeul pour faire un canal de 24 pieds de largeur qui va depuis la bonde du Grand étang, jusqu’à l’ancien réservoir derrière l’office, pour cela les troncs d’arbre de l’ancienne allée, près de la glacière seront arrachés, la terre enlevée servira à continuer les jardins, une bonde sera disposée pour vider le canal, en échange de 500 livres, du logement, de la fourniture d’un tombereau à bras, de trois brouettes.

The emergence of Bluetooth Low Energy in combination with optimized coders has made it possible to transfer digital audio at very low bitrates, paving the way for small devices with longlasting batteries. The aim of this study is to compare the audio codecs LC3 and aptX, as well as peoples’ attitude towards audio quality in different contexts. Two open source implementations of the codecs are evaluated in terms of time for execution. Furthermore, the perceived audio quality of low bitrates are subjectively compared in a listening test in combination with a questionnaire regarding peoples’ attitude towards audio quality. The results show that LC3 is capable of delivering satisfying audio quality at very low bitrates, whilst also outperforming aptX. It will be interesting to see how LC3 will affect transmission latency, battery life and overall QoS once it is established in everyday products

Edouard comte de Bar fait savoir qu’il confirme l’acquisition faite par les moines de Morimond de lui de ses hommes, du seigneur Jean de Choiseul et d’autres : -de huit fauchées de pré et trente trois journaux de terre au-dessus de la chaussée de l’étang de Vrécourt, -d’un ruisseau qui descend des étangs de Sauville pour entrer et venir audit étang de Vrécourt, -d’une rente en blé qu’on appelle « tierce » dans la ville et au finage de Sauxures, le tout pour cent livres tournois. A. Original sur parchemin jadis scellé, Arch. dép. Haute-Marne 8 H 33, Vrécourt n°24. B. Copie partielle, 'cartulaire' de Morimond, (1476-1480), Bibl. mun. Bourbonne-les-Bains, ms. 1, p. 90, n° CCC IIIIxx VI. C. Copie 1630, Arch. dép. Haute-Marne, 8 H 33, Vrécourt n° 24. ANAL : Arch. dép. Haute-Marne, 8 H 75, fol. 197 v°. a. Rouzeau (Benoit), Le patrimoine hydraulique et industriel de l'abbaye cistercienne de Morimond, 2008, …n° LXVI, p. 417.

Marché passé entre Nicolas Aubertain de Mauveignan prieur de l’abbaye de Morimond et Nicolas Briot, Nicolas Léveque entrepreneurs à Ligny en Barrois pour faire les lieux communs entre le grand réfectoire et le bâtiment joignant le canal ou passe les eaux du moulin, refaire les voûtes du canal en simple berceau sous le chauffoir, sous le grand réfectoire, jusqu’au pont de la basse court et le refaire dans le chapitre et la sacristie pour 575 livres payables en quatre fois, les ouvriers seront logés et nourris par le prieur, qui se charge des démolition, de fournir tous les matériaux sur place sauf la pierre de taille que les entrepreneurs tireront de la pierrière de Morimond.

Jean de Veulay sergent au baillage du Bassigny fait savoir qu’il met a exécution des sanctions sur les biens de Nicolas Bourel au profit de l’abbaye de Morimond. Le bail a été passé devant Nicolas Rolin clerc juré de la Mothe le 8 janvier 1524 Il doit quarante émines de blé mesure de Choiseul pour chaque année d’amodiation de cinq moulins, deux dans la clôture et trois en aval de l’abbaye, le moulin neuf, sous la chaussée de l’étang du portier, le moulin foulon et le moulin de Bonne Encontre, pour douze année commençant à la saint Martin d’hiver 1522 en quatre terme de dix émines plus six livres de cire, le jour de la saint Hilaire, octave des rois et d’entretenir le moulin, l’abbé fournissant tuiles, bois et ce qui est nécessaire aux réparations. Nicolas Rolin constate que rien n’a été payé le 30 janvier 1528. Le 28 février 1528, il se transporte à Damblain pour saisir des biens de Nicolas Maille. La saisie est faite le quatre mars et la maison et ses appartenances sont mises en vente sur la place publique le même jour sans succès, une quinzaine passe et le 14 avril 1529 nouvelle séance de vente sans plus de succès. A. Original sur parchemin, jadis scellé, Arch. dép. Haute-Marne 8 H 21, Morimond n° 37. a. Rouzeau (Benoit), Le patrimoine hydraulique et industriel de l'abbaye cistercienne de Morimond, 2008…, n° LXXVII, p. 428, d’après A.

Rockfall, which is the detachment of rocks from a mountain, is a major hazard in the mining industry. To help combat this issue, this thesis aims to develop a sensor platform that is able to detect both the potential risk for rockfall and if any rocks do hit the ground. The platform requires wireless communication in order to output relevant information and in order to be part of an IoT-network of sensors.The design of the platform used three different sensors, a geophone, an accelerometer and a microphone. The main focus of the design process was to keep the platform low power, enabling long operation times. The final design had data output from both the microphone and accelerometer, with the accelerometer able to pick up the impact from a falling barbell. Wireless transmission of data is possible for up to 7.5 meters using Bluetooth Low Energy. The low power design was met, with an average current consumption of 26 milliamperes during transmission using Bluetooth Low Energy. That gives a theoretical operation time of 27 days with the battery used. As the accelerometer can pick up a falling object and with a theoretical lifetime of 27 days for the platform, it can be argued that the goals, except for detecting potential risk for rockfall, were met. In order to properly function, however, the platform needs more development, but the most important conclusion of the work is that it seems possible to build this type of platform. Further research and development outside the scope of the thesis is connecting several platforms together.

Dissertação de mestrado em Physics Engineering (specialization in Devices, Microsystems and Nanotechnologies), The increasing demand for rapid testing stimulates the development of new techniques in clinical diagnosis. When compared to other conventional methods, lateral flow immunoassay has many advantages such as low cost, easy operation, friendly use and quick response. However, it can only give a qualitative or semi quantitative result. Improving the sensibility of the test result and make it quantifiable is a very challenging field of research. Recently, luminescent nanoparticles have been used, and low detection limits have been obtained. One example is quantum dots, which are ideal fluorescent labels and can improve widely the detection sensitivity thanks to their narrow emission spectra, broad excitation range and excellent brightness. This work was focused on making a reader that could read strips targeting biomarkers of COPD (Chronic Obstructive Pulmonary Disease). The new reader was created without a motor dependency, which generally takes a great part of the battery power and the reader’s size. It consists of an acquisition board, a system board and an optical filter. Several simulations and practical tests were made to complete its instrumentation circuit. In order to get dynamic results, a Python Graphic User Interface was made, making it easier for the user to analyse. At last, the reader could perform a 563 ms read, sending the information wirelessly to the computer using a BLE protocol. The device has a changeable sensitivity through programming and a directly proportional response to light intensity., A crescente necessidade para testes rápidos estimulou o desenvolvimento de novas técnicas na área clínica. Quando comparado com outros métodos convencionais, o imunoensaio de fluxo lateral possui muitas vantagens tais como baixo custo, fácil operação, uso amigável e resposta rápida. No entanto, só pode dar um resultado qualitativo ou semi quantitativo. Melhorar a sensibilidade do resultado do teste e torná-lo quantificável é uma área de investigação desafiante. Recentemente, nanopartículas luminescentes têm sido utilizadas, e foram alcançados limites mínimos de deteção. Um exemplo são pontos quânticos, que são marcadores fluorescentes ideais e podem melhorar amplamente a sensibilidade de deteção graças aos seus espectros de emissão estreitos, ampla faixa de excitação e excelente brilho. Este trabalho teve como foco fazer um leitor que pudesse ler tiras direcionadas aos biomarcadores de DPOC (Doença Pulmonar Obstrutiva Crónica). O novo leitor foi criado sem dependência motora, o que geralmente consome grande parte da energia da bateria e do tamanho do leitor. É constituído por uma placa de aquisição, uma placa de sistema e um filtro ótico. Várias simulações e testes práticos foram realizados para completar o seu circuito de instrumentação. Para obter resultados dinâmicos, foi feita uma Interface Gráfica de Utilizador em Python, facilitando a análise do utilizador. Por fim, o leitor conseguia realizar uma leitura em 563 ms, enviando as informações por ligação sem fio BLE para o computador. O dispositivo tem uma sensibilidade variável por meio de programação e uma resposta diretamente proporcional à intensidade da luz.

Dissertação de mestrado integrado em Engenharia Biomédica, A perturbação obsessivo-compulsiva (POC) é uma perturbação neuropsiquiátrica prevalente caracterizada por pensamentos intrusivos recorrentes (obsessões) que podem levar a comportamentos repetitivos (compulsões), que podem causar perturbações significativas no quotidiano. Para estudar simultaneamente os circuitos neuronais envolvidos na POC e testar novas terapias num ambiente pré-clínico, é fundamental desenvolver metodologias que possam automaticamente detetar e/ou prever o comportamento compulsivo e permitir uma modulação eficaz dos circuitos cerebrais relevantes com precisão temporal. Assim, desenvolvemos um sistema de circuito fechado que combina a visão por computador e aprendizagem por máquina para a deteção eficaz em tempo real de comportamentos compulsivos no modelo de ratinho Sapap3 KO da POC, com um estimulador cerebral optogenético controlado sem fios. A deteção exata em tempo real comportamentos repetitivos, tais como o face groom, foi conseguida através da combinação do DeepLabCut para o rastreio em tempo real de partes do corpo animal com a extração supervisionada de características comportamentais cinemáticas e classificação de estados comportamentais com árvores de decisão e Máquinas Vectoriais de Apoio (SVM). A maior sensibilidade e especificidade de classificação foram alcançadas com árvores de decisão, com 85.1% e 98.3%, respetivamente. Foi também desenvolvido e programado um estimulador cerebral ótico alimentado por bateria numa PCB leve (1.43 g) com comunicação Bluetooth de Baixa Energia (BLE). A deteção online de comportamento repetitivo desencadeia o transmissor BLE a enviar um pedido de escrita, com uma latência inferior a 6.67 ms. O sistema completo de ciclo fechado atinge uma latência mínima de apenas 29.9 ms entre o momento em que um sinal BLE é enviado, e o estimulador cerebral ótico responde com parâmetros de estimulação definidos pelo utilizador. Este novo sistema de circuito fechado permite uma avaliação direta do impacto das manipulações dos circuitos cerebrais no comportamento compulsivo, contribuindo para a elucidação dos circuitos cerebrais envolvidos na POC e para o desenvolvimento de novas terapias., Obsessive-compulsive disorder (OCD) is a prevalent neuropsychiatric disorder characterized by recurrent intrusive thoughts (obsessions) that can lead to repetitive behaviors (compulsions), which can cause significant disruption of daily activities. To simultaneously study the neuronal circuits involved in OCD and test novel therapies in a pre-clinical setting, it is critical to develop methodologies that can automatically detect and/or predict compulsive behavior and allow effective modulation of relevant brain circuits with temporal precision. Thus, we developed a closed-loop system that combines computer vision and machine learning approaches for effective real-time detection of compulsive/repetitive behaviors in the Sapap3 KO mouse model of OCD, with a wirelessly controlled optogenetic brain stimulator. Accurate online detection of repetitive behavioral motifs, such as face grooming, was achieved by combining DeepLabCut for real-time animal body part tracking with supervised extraction of kinematic behavioral features and classification of behavioral states with Decisions trees and Support Vector Machines (SVM). The highest classification sensitivity and specificity were achieved with decision trees, with 85.1% and 98.3%, respectively. A battery-powered optical brain stimulator in a lightweight PCB (1.43 g) with Bluetooth Low Energy (BLE) communication was also developed and programmed. Online detection of repetitive behavior triggers the BLE transmitter to send a writing request, with a latency inferior to 6.67 ms. The complete closed-loop system achieves a minimum latency of only 29.9 ms between the moment a BLE signal is sent, and the optical brain stimulator responds with user defined stimulation parameters. This new closed-loop system allows a direct assessment of the impact of brain circuit manipulations in compulsive behavior, contributing to the elucidation of the brain circuits involved in OCD and novel therapies developments., The work included in this dissertation was performed at the Life and Health Sciences Research Institute (ICVS), University of Minho. Financial support was provided by "la Caixa" Banking Foundation under grant agreement LCF/PR/HR21-00410; and national funds through FCT — projects UIDB/50026/2020 and UIDP/50026/2020.

The Battery Management System (BMS) is in charge of monitoring and ensuring the correct operation of the Electric Vehicle (EV) battery. The BMS uses a master slave architecture with a wired daisy chain link. Lately, the industry has seen interest in replacing the wired bus with a wireless network. Wireless BMS (WBMS) brings multiple advantages but at the same time several challenges. In this thesis, we present a complete solution to enable robust wireless communications inside the battery pack of EVs. We propose an enhanced version of the IEEE Std 802.15.4 Time Slotted Channel Hopping (TSCH) Medium Access Control (MAC) mode running over the physical layer of Bluetooth Low Energy(BLE). The network is managed by a reliable and predictable scheduling function based on the Group Acknowledgement (GACK) method. For the parking state of the vehicle, we propose a WBMS sleep mode that reconfigures the network architecture allowing the central node to switch off, preventing the discharge of the small 12 V battery of the EV. We also discuss the new opportunities that the inclusion of a computing capacity in the slaves brings to BMS software development. The laboratory and vehicle test results show that our system provides high reliability, bounded latency, and low power consumption.; Le système de gestion de la batterie (BMS) est chargé de surveiller et garantir le bon fonctionnement de la batterie dans un Véhicule Électrique (VE). Le BMS utilise une architecture maître-esclave avec une liaison filaire entre les capteurs et l’unité de calcul. Dernièrement, l’industrie a vu l’intérêt de remplacer ce bus filaire par une liaison sans fil. Le BMS sans fil (WBMS) peut apporter de nombreux avantages, mais aussi plusieurs défis. Dans cette thèse, nous présentons une solution complète qui rend possible la communication sans fil robuste dans le BMS. Nous proposons une amélioration du protocole d’accès au milieu « Time Slotted Channel Hopping » (TSCH) en conjonction avec la couche physique de Bluetooth Low Energy (BLE). Ce réseau est géré par une fonction d’ordonnancement fiable et prévisible basée sur la méthode d’accusé de réception de groupe (GACK). Nous proposons aussi un mode endormi pour le WBMS qui reconfigure l’architecture du réseau permettant au nœud central de s’éteindre à fin d’éviter la décharge de la petite batterie 12V du VE. Nous discutons également des nouvelles opportunités que l’inclusion d’une capacité de calcul dans les esclaves apporte au développement logiciel du BMS. Les résultats des tests en laboratoire et sur véhicule montrent que notre système offre une haute fiabilité, une latence spécifique et une faible consommation d’énergie.

This paper presents the development of a system able to estimate the 2D relative position of nodes in a wireless network, based on distance measurements between the nodes. The system uses ultra wide band ranging technology and the Bluetooth Low Energy protocol to acquire data. Furthermore, a nonlinear least squares problem is formulated and solved numerically for estimating the relative positions of the nodes. The localization performance of the system is validated by experimental tests, demonstrating the capability of measuring the relative position of a network comprised of 4 nodes with an accuracy of the order of 3 cm and an update rate of 10 Hz. This shows the feasibility of applying the proposed system for multi-robot cooperative localization and formation control scenarios., 6 pages, 12 figures, 2022 IEEE International Symposium on Measurements & Networking (M&N)

In the automotive field, the introduction of keyless access systems is revolutionizing car entry techniques currently dominated by a physical key. In this context, this paper investigates the possible use of smartphones to create a PEPS (Passive Entry Passive Start) system using the BLE (Bluetooth Low-Energy) Fingerprinting technique that allows, along with a connection to a low-cost BLE micro-controllers network, determining the driver’s position, either inside or outside the vehicle. Several issues have been taken into account to assure the reliability of the proposal; in particular, (i) spatial orientation of each microcontroller-based BLE node which ensures the best performance at 180° and 90° referred to as the BLE scanner and the advertiser, respectively; (ii) data filtering techniques based on Kalman Filter; and (iii) definition of new network topology, resulting from the merger of two standard network topologies. Particular attention has been paid to the selection of the appropriate measurement method capable of assuring the most reliable positioning results by means of the adoption of only six embedded BLE devices. This way, the global accuracy of the system reaches 98.5%, while minimum and maximum accuracy values relative to the individual zones equal, respectively, to 97.3% and 99.4% have been observed, thus confirming the capability of the proposed method of recognizing whether the driver is inside or outside the vehicle.

The Internet of Things (IoT) interconnects massive cyber-physical devices (CPD) to provide various applications, such as smart home and smart building. Bluetooth Mesh is an emerging networking technology, which can be used to organize a massive network with Bluetooth Low Energy (BLE) devices. Managed-flooding protocol is used in Bluetooth Mesh to route the data packets. Although it is a highly desirable option when data transmission is urgent, it is inefficient in a larger and denser mesh network due to the collisions of broadcast data packets. In this paper, we introduce ACE: a Routing Algorithm based on Autonomous Channel Scheduling for Bluetooth Mesh Network. ACE relies on the existing Bluetooth Mesh messages to distribute routes without additional traffic overhead and conducts a beacon-aware routing update adaptively as the topology evolves. In ACE, BLE channel resources can be efficiently utilized by a channel scheduling scheme for each node locally and autonomously without any neighborly negotiation. We implement ACE on the nRF52840 from Nordic Semiconductor and evaluate its effectiveness on our testbed. Compared to the Bluetooth Mesh, our experiments proved that ACE could reduce the end-to-end latency by 16%, alleviate packets collisions issues, and increase the packet delivery ratio (PDR) by 30% under heavy traffic. Moreover, simulation results verified that ACE has better scalability when the size and density of networks become larger and denser.

Utilizando apenas uma gateway Pinnacle 100 e dispositivos Air Quality Sensor (AQS) de pequena dimensão, esta dissertação demonstra como é possível implementar uma rede Bluetooth Low Energy, entre os AQS e a gateway, para troca dos valores dos sensores neles integrados, bem como uma ligação LTE-M para envio dos mesmos da Pinnacle 100 para a cloud, Amazon Web Services (AWS). Com o passar dos anos, desenvolvimento da tecnologia e procura incessante, por parte de todo o tipo de indústrias e empresas, por uma redução geral de custos, manifesta-se a necessidade e oferta para a solução desenvolvida nesta dissertação. Esta surge com o objetivo de reduzir o custo da monitorização e controlo de diversos ambientes e situações, ao eliminar a necessidade de mão de obra humana e os custos associados aos erros que essa possa causar. Em parceria com a WiseWare Solutions, não só foram estudadas as tecnologias existentes como também desenvolvida a presente solução. Por fim, quando já completa, esta foi testada em diferentes locais e situações para se conseguir tirar conclusões e comprovar o seu funcionamento. Por último, a solução foi capaz de receber os dados dos sensores integrados nos AQS, processá-los e enviar para a cloud AWS, onde aí ficam disponíveis para situações de monitorização, em tempo real, onde quer que haja ligação à Internet. Using only the Pinnacle 100 gateway and AQS devices, this dissertation demonstrates how it is possible to implement a Bluetooth Low Energy network, between the gateway and AQS, to allow the exchange of values read by the sensors integrated in them, along with a LTE-M connection to send the data to the AWS cloud. Along the years, with the development of technology and the insatiable desire, in all kinds of industries and companies, to lower overall costs, the need for the solution described in this dissertation arises. The solution aims for reducing costs and be able to monitor and control diverse environments and situations, by passing the need for human labor and the expenses that it brings in case of its mistakes and errors. In partnership with WiseWare Solutions, not only were the existing technologies studied, but also was the present solution developed. When complete, the latter was tested in a number of situations and environments to extract conclusions and to check its functioning. In the end, the solution was able to receive the data from the integrated sensors in the AQS, process and send them to the cloud, with the opportunity to be monitored, in real time, anywhere with a Internet connection. Mestrado em Engenharia Eletrónica e Telecomunicações

ilustraciones, fotografias, graficas, mapas La navegación en ambientes cerrados puede llegar a ser compleja, especialmente para personas con discapacidad visual. Para asistir la navegación en ambientes cerrados se han propuesto sistemas de navegación interior (SNIs) que involucran tecnologías como WiFi, Bluetooth, RFID entre otras, las cuales son diferentes a los habituales Sistemas Globales de Navegación por Satélite (GNSS) porque estos son ineficientes por la pérdida de la señal que provoca la estructura de los edificios. Por otra parte, para asistir la navegación de personas con discapacidad se han propuesto soluciones que involucran el reconocimiento de obstáculos y espacios por medio de cámaras y sensores, lo cual resulta costoso de implementar. Por lo mencionado, se requiere la exploración de metodologías para el desarrollo de SNIs que logren un equilibrio entre costo de implementación, rendimiento, exactitud en la ubicación y sobre todo que proporcione información útil a las personas con discapacidad. El propósito de esta investigación fue proponer un sistema de navegación interior (SNI) orientado a usuarios con discapacidad visual, integrando los estándares del OGC IndoorGML y CityGML, para la construcción de los modelos semánticos y de representación 3D; en conjunto con el uso de la tecnología BLE, el valor de pérdida de señal RSSI y la técnica Weighted Path Loss (WPL) para calcular la ubicación del usuario. El desarrollo del SNI se inició con la definición de los requerimientos, posteriormente se desarrolló cada componente hasta obtener como resultado tangible el prototipo funcional de una aplicación web móvil, con la cual se desarrollaron diferentes pruebas para determinar la precisión y exactitud de la ubicación calculada. Los resultados indican que se logró un error de 0.63m en un escenario sin obstáculos y sin diferencias de altura; un error de 0.86m en un escenario con obstáculos y sin diferencia de altura y un error de 1.06m en un escenario con obstáculos y con diferencia de altura. Dichos resultados confirman el potencial del prototipo desarrollado para evolucionar en un sistema operacional. (Texto tomado de la fuente) Indoor navigation can become complex, especially for visually impaired people. To assist indoor navigation, systems have been proposed that involve technologies such as WiFi, Bluetooth, RFID, among others, which are different from the usual Global Navigation Satellite Systems (GNSS) because they are inefficient due to the loss of signal caused by the structure of buildings. On the other hand, to assist the navigation of people with disabilities, solutions have been proposed that involve the recognition of obstacles and spaces by means of cameras and sensors, which is costly to implement. Therefore, it is required the exploration of methodologies for the development of indoor navigation systems that achieve a balance between implementation cost, performance, location accuracy and above all that provide useful information to people with disabilities. The purpose of this research was to propose an indoor navigation system oriented to visually impaired users, integrating the OGC IndoorGML and CityGML standards, for the construction of semantic models and 3D representation; together with the use of BLE technology, the RSSI signal loss value and the Weighted Path Loss (WPL) technique to calculate the user's location. The development of the system started with the definition of the requirements, then each component was developed until obtaining as a tangible result the functional prototype of a mobile web application, with which different tests were developed to determine the precision and accuracy of the calculated location. The results indicate that an error of 0.63m was achieved in a scenario without obstacles and without height difference; an error of 0.86m in a scenario with obstacles and without height difference and an error of 1.06m in a scenario with obstacles and with height difference. These results confirm the potential of the developed prototype to evolve into an operational system. Maestría Magíster en Geomática Tecnologías Geoespaciales

– The problems regarding prisons are almost endless. The government should pay attention to this. The problems that arise today, almost all correctional institutions in Indonesia exceed (over) capacity, including those in the East Kotawaringin district . Indoor Positioning System IPS is a technology that can be used to locate people or objects in a building, usually through a mobile device such as a smartphone or tablet. Although this technology is newer than GPS, services utilizing IPS are quickly gaining ground in indoor locations such as shopping malls, hospitals, airports and other indoor venues. By utilizing an iBeacon mounted on a prisoner's wristband, the iBeacon will always transmit a signal that can be picked up by the receiver. Devices that can become receivers are bluetooth repeaters (signal boosters) and prison officers' android phones. To be able to know the estimated position of the receiver on the iBeacon, a map is needed locally, which is to determine a certain location, then map it in the form of coordinates. By placing several iBeacons at certain coordinates, it can be used to determine the estimated position of the receiver to the iBeacon., Persoalan mengenai lapas hampir tidak ada habisnya. Seharusnya hal ini perlu diperhatikan oleh pihak pemerintah. Permasalahan yang timbul saat ini, hampir di semua Lembaga Pemasyarakatan yang ada di Indonesia melebihi (over) kapasitas termasuk yang ada di kabupaten Kotawaringin Timur. Indoor Positioning System IPS merupakan sebuah teknologi yang dapat digunakan untuk menemukan orang atau benda di dalam gedung, biasanya melalui perangkat seluler seperti ponsel pintar atau tablet. Meskipun teknologi ini lebih baru daripada GPS, layanan yang memanfaatkan IPS dengan cepat mendapatkan tempat di lokasi-lokasi indoor seperti pusat perbelanjaan, rumah sakit, bandara dan tempat-tempat dalam ruangan lainnya. Dengan memanfaatkan iBeacon yang dipasang pada gelang narapidana maka iBeacon akan selalu memancarkan sinyal yang dapat ditangkap oleh receiver. Perangkat yang dapat menjadi reiver yaitu bluetooth repeater (penguat sinyal) maupun HP android petugas lapas. Untuk bisa mengetahui estimasi posisi receiver terhadap iBeacon secara pasti diperlukan peta secara lokal, yaitu menentukan sebuah lokasi tertentu, kemudian dipetakan dalam bentuk koordinat. Dengan meletakkan beberapa iBeacon pada koordinat tertentu akan dapat digunakan untuk mengetahui estimasi posisi receiver terhadap iBeacon.

La Tunisie connaît au début des années 1920 une série de mauvaises récoltes de blé tendre, principalement dues à la sécheresse. Alors que la production annuelle était supérieure à 550 000 quintaux en 1918, quatre années de baisse de production s’ensuivent, dans une colonie déjà affaiblie par la Première Guerre mondiale. Cette faiblesse des récoltes a des conséquences sur le prix des blés, de la farine et du pain. À partir de la correspondance de la haute administration (secrétariat général du gouvernement, cheikh el Medina, contrôle civil) et de la presse, cet article vise à comprendre le passage d’une crise environnementale à une crise sociale dans un contexte colonial. Il s’agit de cerner les arbitrages effectués pour gérer les augmentations des prix, face aux pressions des populations comme des professionnels du pain. Tunisia experienced a series of poor wheat harvests in the early 1920s, mainly due to drought. While annual production was over 550,000 quintals in 1918, four years of declining production ensued, in a colony already weakened by the First World War. This low harvest had consequences for the price of wheat, flour and bread. Based on correspondence between senior members of the administration (from the General Secretariat of the Government, the Sheikh el Medina, and civilian oversight roles) and the press, this article seeks to understand the transition from an environmental crisis to a social crisis in a colonial context by identifying the negotiations made to manage price increases in the face of pressure from the population, as well as bread professionals.

Na bazi ESP32 mikrokontrolerja je bil izdelan sistem avtomatskega zalivanja z beleženjem podatkov v spletni podatkovni bazi. Sistem je sestavljen iz glavnega mikrokontrolerja, ki skrbi za komunikacijo med ostalimi mikrokontrolerji in spletno podatkovno bazo. Komunikacija med glavnim mikrokontrolerjem in ostalimi poteka v času seznanjanja preko protokola BLE, nato pa se vsa komunikacija vrši preko protokola esp-now. Izdelana je bila tudi spletna stran, preko katere uporabnik spremlja podatke mikrokontrolerjev, dodaja nove mikrokontrolerje v omrežje in spreminja nastavitve. Based on the ESP32 microcontroller, an automatic watering system was created with data recording in an online database. The system consists of the main microcontroller, which takes care of the communication between other microcontrollers and the online database. Communication between the main microcontroller and others uses BLE protocol during pairing, after that all communication is done with the esp-now protocol. A website was also created, through which the user can monitor microcontroller data, add new microcontrollers to the network and change settings.

Bluetooth Low Energy (BLE) and IEEE 802.15.4 Time-Slotted Channel Hopping (TSCH) are widely used low-power standard technologies developed for short-range communications in the internet-of-things. In many applications, BLE and TSCH networks may be deployed in the vicinity of one another, which may lead to Cross Technology Interference (CTI) influencing each other's performance. Both technologies utilize channel hopping to alleviate the impact of external interferences. However, having a model to quantitatively estimate the performance of coexisting TSCH and BLE networks and analyze the role of networks' configuration settings is still an open problem. To address this, we provide a probabilistic analysis of collision-free communication of coexisting BLE and TSCH networks. Moreover, a fast coexistence simulation model is developed that computes the ratio of collision-free transmissions. This model is used to investigate how the performance of the coexisting networks may deviate from the results of the probabilistic analysis. It gives the designers a proper estimation of the worst case performance degradation due to such coexistence. It is shown that severity of the impact of coexisting BLE-TSCH networks on one another depends on the setup configurations and the relative timing of the two networks. The results show that these two technologies can coexist well with collision-free ratios of more than 92.58% and 96.29% in the tested configurations for TSCH and BLE, respectively.

Drones are widely known for their mobility and ease of use and represent a significant technological breakthrough with various applications. In this paper, a novel inexpensive Search and Rescue (SAR)-based approach for application in indoor environments is presented. The usage of Bluetooth Low Energy (BLE) has been evaluated with respect to other technologies and a conceptual view of the complete setup has been presented. Besides the cost of the drone and the locator devices, the other hardware is relatively inexpensive costing only a fraction of a US dollar. The system is believed to cover a wide area in a small-time frame ranging a few minutes, for instance, a 3600m2 surface area could be scanned in less than 5 minutes. The system is tested by attaching a BLE device in the payload to evaluate the presence of target beacons. Potential upgrades in the system are also proposed, including design modifications for outdoor use and the application in locating missing objects. This system can confidently replace search parties dealing with missing children in public places or venues, with minimal human interaction while bearing the potential for complete automation.

The growth of Internet of Things in recent years has led to the use and dissemination of various technologies to achieve the concept of connected life. Some of the most common technologies that enable the implementation of the IoT concept are ZigBee, 6LoWPAN, and BLE. The main obstacle to the realization of this is the provision of quality service. The study of parameters affecting the Quality of Service can be used as a means to improve the service of objects and select a more appropriate wireless technology to communicate with them. This paper constructs an IoT network with Texas Instruments CC2650STK sensors that can be monitored and controlled with each of these technologies. The research was performed on a different sensor, at different distances from the network servicing device and for each of the technologies, the following parameters characterizing QoS were measured – End_to_End Delay, Throughput, and Packet Loss Ratio. A comparative analysis for the impact of each of the considered wireless technologies on studied parameters is presented to formulate recommendations for selecting the most appropriate technology for the respective type of IoT application.

Bluetooth Low Energy (BLE) is a positioning technology that is commonly used in indoor positioning systems (IPS) such as shopping malls or underground parking lots, because of its low power consumption and the low cost of Bluetooth devices. It also maintains high positioning accuracy. Since the cost of BLE itself is low, it has now been used in larger environments such as parking lots or shopping malls for a long time. However, it is necessary to configure a large number of devices in the environment to obtain accurate positioning results. The most accurate method of using signal strength for positioning is the signal pattern-matching method. The positioning result is compared through a database with the overheads of time and labor costs, since the amount of data will be proportional to the size of the environment for BLE-IPS. A planar model that conforms to the signal strength in the environment was generated, wherein the database comparison method is replaced by an equation solution, to improve various costs but diminish the positioning accuracy. In this paper, we propose to further replace the planar model with a cost-effective fitting model to both save costs and improve positioning accuracy. The experimental results demonstrate that this model can effectively reduce the average positioning error in distance by 31%.

Obstacle avoidance is a key aspect for any autonomous vehicles, and their usage in agriculture must overcome additional challenges such as handling interactions with agricultural workers and other tractors in order to avoid severe accidents. The simultaneous presence of autonomous vehicles and workers on foot definitely calls for safer designs, vehicle management systems and major developments in personal protective equipment (PPE). To cope with these present and future challenges, the “SMARTGRID” project described in this paper deploys an integrated wireless safety network infrastructure based on the integration of Bluetooth Low Energy (BLE) devices and passive radio frequency identification (RFID) tags designed to identify obstacles, workers, nearby vehicles and check if the right PPE is in use. With the aim of detecting workers at risk by scanning for passive RFID-integrated into PPE in danger areas, transmitting alerts to workers who wear them, tracking of near-misses and activating emergency stops, a deep analysis of the safety requirements of the obstacle detection system is shown in this study. Test programs have also been carried out on an experimental farm with detection ranging from 8 to 12 meters, proving that the system might represent a good solution for collision avoidance between autonomous vehicles and workers on foot.

Kot del relativno novega področja je komunikacija z napravami IoT še vedno odprta tema. Glavna pomanjkljivost dosedanjih rešitev je fragmentacija in kompleksnost uporabe. Za projekte manjšega obsega zato postane problem odkrivanja naprav in komunikacije med napravami precej velika ovira. Da bi jo presegli, smo razvili protokol MultiCom in množico knjižnic, ki omogočajo celovito in preprosto rešitev za komunikacijo mobilne naprave z napravami IoT. Rešitev smo preizkusili tudi z vključitvijo v obstoječi projekt izdelave mobilne aplikacije za upravljanje pametnih infrardečih grelcev. As part of a relatively new field, the problem of communication with IoT devices remains an open question. The main disadvantage of current solutions is the fragmentation and complex usage. For smaller projects, the problem of device discovery and communication between devices becomes a relatively big burden. To overcome it, we have developed the protocol MultiCom and a set of libraries, enabling a complete and simple solution for a mobile device to communicate with IoT devices. We have set ourselves a goal of solving this problem with a protocol and a set of libraries that simplify the communication of a mobile device with an IoT device. We tested the solution by including it in an existing project of developing an application to manage smart infrared heaters.

The growing interest in Internet of Things technologies in modern life requires their active research. This can be done most easily by using a simulation product for the technology in consideration. This article presents the most famous existing simulation products of Bluetooth Low Energy technology, as well as the one developed by the authors, and presents a comparison between the considered solutions.

Ovaj diplomski rad bavi se temom upravljanja pametnom utičnicom pomoću mikroprocesora ESP32 i prateće Android aplikacije koja komunicira s utičnicom pomoću Bluetooth-a. Na početku rada opisana je situacija gdje se može naći primjena i zašto bi itko radio ovakvu utičnicu. Dalje vidimo po kojem principu će taj sustav raditi, te nakon toga je opisano koje fizičke komponente i koje programske komponente se koriste. Slijedno tome vide se funkcionalnosti sustava sa njihovim pojedinačnim ispisima zaslona. Na kraju se nalaze korištene tehnologije za takav sustav. This thesis deals with the Smart Plug system using the ESP32 microprocessor and Android application which communicate via Bluetooth Low Energy. At the beginning of the paper, a situation is described where application can be found and why anyone would work with such system. Next we see on what principle this system will work, and after that it is described which physical components and which program components are used. Consequently, the functionalities of the system are seen with their individual screen prints, and at the end there are the technologies used for that system.

U ovom radu implementiran je sustav za prijam, prikaz i obradu audio signala korištenjem razvojnog sustava STM32WB5MM-DK. Korištene su biblioteke koje omogućavaju snimanje zvuka MEMS mikrofonom na razvojnom sustavu. Korišteno je BLE sučelje za prijenos audio signala s razvojnog sustava na računalo. Razvijeno je grafičko korisničko sučelje za snimanje zvuka i vizualizaciju ranije snimljenih podataka korištenjem razvojnog alata PyQt. Aplikacija se izvodi na operacijskom sustavu Linux. Provedena je analiza zvučnih zapisa hrkanja snimljenih razvijenim sustavom. This thesis describes an implementation of a system for receiving, displaying and analysis of audio signal using STM32WB5MM-DK development board. Libraries that enable audio recording with a MEMS microphone on the development board have been used. BLE interface is used for signal transfer from the STM32WB5MM-DK to the computer. A graphical user interface has been developed for audio recording and audio signal visualization, using PyQt development tools. The application runs on the Linux operating system. Analysis of snoring audio recorded with the developed system has been performed.

Sustavi Interneta stvari imaju široku primjenu u današnjici, te se ona neprestano povećava. Budući da navedeni sustavi koriste IoT uređaje koji se napajaju putem nekog izvora električne energije (baterije, solarne ćelije i sl.), u cilju je da ta potrošnja bude minimalna kako bi sustav samostalno funkcionirao što dulje. Upravo zato su osmišljeni komunikacijski protokoli kao što su Bluetooth Low Energy i MQTT čija je implementacija objašnjena i demonstrirana u ovome radu. Koncept interneta stvari također sadrži uređaje koji dohvaćaju podatke i međusobno komuniciraju, te poslužitelje koji prikupljaju podatke i kasnije manipuliraju njima. ESP32 mikroupravljač jednostavan je IoT uređaj koji ima podržanu BLE tehnologiju i pruža mogućnost jednostavnog programiranja putem Arduino IDE, stoga je on korišten u radu. Poslužitelj koji je također korišten u radu jest MQTT Broker, koji se nalazi na IoT platformi Home Assistant podignute na virtualnom stroju. Home Assistant platforma pruža puno veće mogućnosti nego što su prikazane u radu, no zbog zahtjeva demonstrativnog sustava Interneta stvari on se koristi samo kao MQTT poslužitelj s mogućnošću prikaza dolaznih MQTT poruka. U cjelini, IoT sustav korišten u petljaradu imitira sustav koji bi dohvaćao podatke o temperaturi s krajnjeg uređaja, te kojim bi se moglo upravljati samo putem MQTT poruka. Završno, sustav je pogodan za daljnju nadogradnju, te bi se u budućnosti mogao integrirati protokol HTTP i spremati podatke u bazu podataka kako bi se putem web aplikacija moglo dohvaćati podatke i upravljati uređajima ili bi se moglo dodati još IoT uređaja u sustav i isprobati BLE „mesh“ tehnologiju. Internet of Things systems are widely used today and they are constantly increasing. Since these systems use IoT devices that are powered by some source of electricity (batteries, solar cells, etc.), the aim is to keep this consumption to a minimum so the system can operate independently for as long as possible. That is why communication protocols such as Bluetooth Low Energy and MQTT were designed and implementation of which is explained and demonstrated in this work. The concept of the Internet of Things also includes devices that retrieve data and communicate with each other and servers that collect data and later manipulate it. The ESP32 microcontroller is a simple IoT device that has BLE technology supported and provides easy programming via the Arduino IDE, so it has been used in this work. The server that was also used in the work is MQTT Broker, which is located on the IoT platform Home Assistant, built on a virtual machine. The Home Assistant platform provides much greater capabilities than shown in the paper, but due to the requirements of the Internet of Things demonstration system, it is only used as an MQTT server with the ability to display incoming MQTT messages. On the whole, the IoT system used in the paper mimics a system that would retrieve temperature data from the end device, and which could only be controlled via MQTT messages. Finally, the system is suitable for further upgrades, and in the future the HTTP protocol could be integrated and data stored in a database so that data could be retrieved and managed via web applications or more IoT devices could be added to the system and BLE tested, mesh technology.

Bluetooth ha sido una tecnología muy utilizada para la transferencia de información. Sin embargo, con el auge de los dispositivos IoT como wearables se puso de manifiesto la necesidad de perfeccionar esta tecnología. Esta mejora estuvo enfocada al bajo consumo y potencia, y tuvo como resultado el Bluetooth Low Energy. Este proyecto se centra en la implementación de dos subsistemas de comunicación BLE. Cada subsistema se centrará en un rol del SoC BLE (central/periférico) que reciba/envíe datos mediante BLE. El primer subsistema adquiere los datos de un sensor de nivel de agua en un móvil. El sensor es el encargado de enviar los datos captados hacia el microcontrolador el cual los envía hacia el SoC y este mediante BLE al teléfono móvil. El segundo adquiere los datos de un sensor en un ordenador. El sensor está integrado en una plataforma junto con el SoC BLE (que actuará como periférico) que enviará los datos hacia otro SoC BLE el cual mostrará los datos en el ordenador. Primero se ha llevado a cabo un estudio de diferentes dispositivos a usar para cada uno de los subsistemas eligiendo el óptimo en cada caso. Posteriormente se realizado el diseño hardware y la programación firmware. Obtendremos dos prototipos sobre los que se realizarán las pruebas pertinentes que permitan corroborar su funcionamiento correcto y que se ha logrado un diseño de bajo consumo, potencia y coste. Las conclusiones versarán sobre los resultados obtenidos y las líneas futuras que optimizarían el diseño realizado. Bluetooth has been a widely used technology for information transfer. However, with the rise of IoT devices such as wearables, the need to improve this technology became apparent. This improvement was focused on low power consumption and low power, and resulted in Bluetooth Low Energy. This project focuses on the implementation of two BLE communication subsystems. Each subsystem will focus on one role of the BLE SoC (central/peripheral) that receives/sends data via BLE. The first subsystem acquires data from a water level sensor in a mobile phone. The sensor sends the captured data to the microcontroller, which sends it to the SoC and the SoC sends it via BLE to the mobile phone. The second one acquires the data from a sensor in a computer. The sensor is integrated in a platform together with the BLE SoC (which will act as a peripheral) which will send the data to another BLE SoC which will display the data on the computer. First, a study of different devices to be used for each of the subsystems has been carried out, choosing the optimal one in each case. Subsequently, the hardware design and firmware programming were carried out. We will obtain two prototypes on which the relevant tests will be carried out to corroborate that they work correctly and that a low consumption, power and cost design has been achieved. The conclusions will be based on the results obtained and the future lines that would optimise the design carried out. Bluetooth ha estat una tecnologia àmpliament utilitzada per a la transferència d'informació. Tanmateix, amb l'augment dels dispositius IoT com a portables, es va revelar la necessitat de millorar aquesta tecnologia. Aquesta millora es va centrar en un baix consum i energia i va donar lloc a la baixa energia Bluetooth. Aquest projecte se centra en la implementació de dos subsistemes de comunicació BLE. Cada subsistema se centrarà en un paper del SOC (central/perifèric) que rep/envia dades de BLE. El primer subsistema adquireix les dades d'un sensor de nivell d¿aigua en un mòbil. El sensor s¿encarrega d¿enviar les dades capturades al microcontrolador que les envia al SOC i això per MOBA al telèfon mòbil. El segon adquireix les dades d'un sensor en un ordinador. El sensor s'integra en una plataforma juntament amb el SOC BLE (que actuarà com a perifèric) que enviarà les dades a un altre SOC BLE que mostrarà les dades de l'ordinador. En primer lloc, s'ha realitzat un estudi de diferents dispositius que s'han d'utilitzar per a cadascun dels subsistemes escollint òptims en cada cas. Posteriorment, disseny de maquinari i programació de firmware. Obtindrem dos prototips sobre els quals les proves rellevants que permeten corroborar la seva operació correcta i que es realitzarà un baix consum, potència i disseny de costos. Les conclusions tractaran els resultats obtinguts i les línies futures que optimitzessin el disseny realitzat.

Bluetooth has solidified its status as one of the most prominent and versatile wireless communication technologies alongside Wi-Fi. In spite of its widespread usage, contemporary Bluetooth testing technology still has many unaddressed shortcomings and issues. Hardware limitations, computational complexity, and the lack of standardization are some of these longstanding problems. Furthermore, very few systems possess a proven and reliable capability to test both Wi-Fi and Bluetooth. This paper presents the development of an adaptive Bluetooth test-bed framework that can not only overcome limitations with existing systems but can accommodate other technologies and protocols as well. The work presented in this paper includes: a packet processing and logging utility, a promiscuous packet capture subsystem built around a production test engine, and a complementary subsystem that handles encryption and other security mechanisms.

The global navigation satellite system (GNSS) is widely used in smartphone positioning, but its performance can be degraded in urban environments because of signal reflections or blockages. To address these GNSS outages, pedestrian dead reckoning (PDR) is commonly used due to its significant improvements in both the stability and continuity of positioning, which are dependent on three key factors: continuous absolute position, heading and step information. Signals of opportunity are commonly used in positioning, whereas the installation of Bluetooth low energy (BLE) sensors on lampposts can provide an opportunity for positioning and heading estimation in urban canyons. In this article, a system integrating the GNSS, PDR, and BLE techniques is implemented in smartphones to provide a real-time positioning solution for pedestrians, which includes a new position correction method based on BLE heading, a reliable heading estimation integrating BLE and inertial sensors, an unconstrained step detection method with high accuracy, and an extended Kalman filter (EKF) to integrate multiple sensors and techniques. In several field experiments, with improvements in availability and robustness, the heading accuracy of the proposed fusion approach could reach approximately 3 degrees; the positioning accuracy achieved between 2.7 m and 4.2 m, compared with a 30 m error from the GNSS alone. Simultaneously, this system could achieve a high positioning accuracy of 2.4 m with unconstrained smartphones in a mixed environment. The proposed system has been demonstrated to perform well in urban canyons.

The beta regression model has become a popular tool for assessing the relationships among chemical characteristics. In the BRM, when the explanatory variables are highly correlated, then the maximum likelihood estimator (MLE) does not provide reliable results. So, in this study, we propose a new modified beta ridge-type (MBRT) estimator for the BRM to reduce the effect of multicollinearity and improve the estimation. Initially, we show analytically that the new estimator outperforms the MLE as well as the other two well-known biased estimators i.e., beta ridge regression estimator (BRRE) and beta Liu estimator (BLE) using the matrix mean squared error (MMSE) and mean squared error (MSE) criteria. The performance of the MBRT estimator is assessed using a simulation study and an empirical application. Findings demonstrate that our proposed MBRT estimator outperforms the MLE, BRRE and BLE in fitting the BRM with correlated explanatory variables.

Due to the popularity of short-range communications and the ultra-dense deployment of the Internet of Things (IoT), the occurrence of severe signal collision in crowded nodes is becoming increasingly critical. We propose a scheme called anti-collision voting based on Bluetooth low energy improvement for the ultra-dense edge, in which one topic can be identified and separated from the others to enable intensive voting. The scheme alleviates the exponential growth of advertising collisions and achieves efficient consensus between the devices and humans by localized the message advertising. The previous proposals focused on enhancing the hardware and optimizing the parameters to establish a connection for interaction. Considering the limitation of connective devices, our scheme adopts a novel advertising model in which the nodes can promptly exit the advertising state by actively responding. In addition, the scheme merges active responses into a group to notify the advertising nodes and randomly chooses a channel to reduce redundancy and save energy. The simulations demonstrate that the scheme can reduce the collisions by more than 90% and channel occupancy by half, while doubling the capacity and efficiently supporting intensive voting within edge networks.

A wireless self-powered temperature sensor node is presented. This sensor node is powered by a commercially available indoor photovoltaic energy harvester module. The sensor node uses Bluetooth® Low Energy as wireless connection. Both the hardware and firmware have been optimized to obtain a very low power consumption. An auto adaptive energy management routine has been implemented to extend the autonomy of the sensor node. The system consumption and photovoltaic generation have been characterized at different conditions, obtaining a tool to estimate the autonomy of the system. The system has also been tested in a climatic chamber to study the effect of the temperature, a key factor that affects the power consumption, and hence the autonomy of the sensor.

The risk of COVID-19 transmission increases when an uninfected person is less than 6 ft from an infected person for longer than 15 minutes. Infectious disease experts working on the COVID-19 pandemic call this high-risk situation being Too Close for Too Long (TCTL). Consequently, the problem of detecting the TCTL situation in order to maintain appropriate social distance has attracted considerable attention recently. One of the most prominent TCTL detection ideas being explored involves utilizing the Bluetooth Low-Energy (BLE) Received Signal Strength Indicator (RSSI) to determine whether the owners of two smartphones are observing the acceptable social distance of 6 ft. However, using RSSI measurements to detect the TCTL situation is extremely challenging due to the significant signal variance caused by multipath fading in indoor radio channel, carrying the smartphone in different pockets or positions, and differences in smartphone manufacturer and type of the device. In this study we utilize the Mitre Range Angle Structured (MRAS) Private Automated Contact Tracing (PACT) dataset to extensively evaluate the effectiveness of Machine Learning (ML) algorithms in comparison to classical estimation theory techniques to solve the TCTL problem. We provide a comparative performance evaluation of proximity classification accuracy and the corresponding confidence levels using classical estimation theory and a variety of ML algorithms. As the classical estimation method utilizes RSSI characteristics models, it is faster to compute, is more explainable, and drives an analytical solution for the precision bounds proximity estimation. The ML algorithms, Support Vector Machines (SVM), Random Forest, and Gradient Boosted Machines (GBM) utilized thirteen spatial, time-domain, frequency-domain, and statistical features extracted from the BLE RSSI data to generate the same results as classical estimation algorithms. We show that ML algorithms can achieve 3.60%~19.98% better precision, getting closer to achievable bounds for estimation.

Introduction. Localization of objects position in closed space plays an important role in many areas of human activity, including medicine. Using indoor-positioning technologies as a part of telemedicine systems allows one to improve the quality of medical care and to reduce mortality of patients. Therefore, indoor-positioning technologies contribute to achieve the goals outlined in the Russian Federation government`s program "Healthcare development". Aim. To study the applicability of modern radiofrequency technologies for localization of patients inside a hospital building. Materials and methods. Scientific sources devoted to indoor-positioning based on radiofrequency technologies were analyzed. The methods used included: - bibliographic retrieval; - selection and verification of sources based on their relevance; - analysis of sources by methods of deconstruction and comparative analysis . Results. The result of the analysis indicated that radiofrequency positioning technologies allow one to locate objects using radio waves properties. The disadvantage of the technology is the penetration of radio signal through walls and floors. Given this, it is necessary to use complex algorithms to detect an object with accuracy to a specific room. Despite this disadvantage, radiofrequency technologies can be used for positioning in medical facilities since they are easy in deployment and service. Also, they are used in ready-made commercial solutions. ZigBee technology is an exception because it does not allow one to track moving objects in real-time. Conclusion. Based on the study it was concluded that BLE technology is the most suitable for indoor-positioning in medical facilities. It is energy-efficient, it has sufficiently fast data transfer rate, good communication radius and a large range of ready-made communication equipment. It is also worth noting that most wireless medical sensors exchange data via the BLE interface.

Taking care of students is effective work to avoid repeating a year or dropping out in education institutes. As taking care process, human relations among students is a related factor to find a care-required student. Additionally, dynamic changes in human relations require continuous recognition of students to taking care. As the recognition scheme of students, indoor positioning methods are candidate technology to track students with cheap wireless devices. Bluetooth, WiFi, and IEEE 802.1.5.4 are usually used for conventional service according to the decreasing costs of the devices. Bluetooth Low Energy (BLE) is the low energy standard of Bluetooth and is suitable for long operation with a battery. Since the authors have been proposed a concept design of an estimation scheme for social graph based on occupancy time in space, this paper extends the proposed position estimation scheme. It evaluates the estimation performance of the grid position as the fundamental location information for the social graph estimation. The proposed scheme uses a BLE beacon to track each student and recognizes a student share time in the same space. It also estimates social relations among students. We have developed a prototype system for tracking BLE beacon and estimating a location according to RSS values from the BLE beacon. In the evaluation, we have developed a special classifier to estimate a grid position according to the received RSS values. The classifier is trained by actual measurement data. The evaluation results show that the classifier can estimate a correct grid position with more than 90% by receiving one set of RSS values.