01923nas a2200157   4500008004100000245007300041210006900114520131600183100002101499700001801520700002201538700002401560700002201584700002601606856013301632       2020                        eng d00aGuideMe: A Networked Application for Indoor Orientation and Guidance0 aGuideMe A Networked Application for Indoor Orientation and Guida3 aToday’s indoor navigational systems are more and more in demand, commonly used for applications such as smart cities, robots and visually impaired people. As far as outdoor navigation is concerned, the Global Positioning System (GPS) technology is still one of the most (if not the most) commonly used approaches. Even though it is still considered an ideal solution for navigating in outdoor areas, challenges and problems arise when GPS is considered for navigation inside buildings due to obstacles (e.g., shopping malls, hospitals, etc.) and because signals cannot be absorbed by the building walls. To tackle the aforementioned issue, other technologies have emerged aimed at indoor navigation, such as Wireless-Fidelity (Wi-Fi), Bluetooth and sensors. This paper’s contribution is towards indoor navigation and, more specifically, it targets designing and developing a tracking and navigation system aimed at people that experience difficulties in indoor orientation using a wearable device. The user takes direction from the wearable device for the indoor orientation through voice commands helping him to avoid obstacles. The central part of the system is a device that provides the ability to navigate and find a route by voice commands, based on the device's location and orientation capabilities.1 aBouras, Christos1 aBarri, Eirini1 aGkamas, Apostolos1 aKoulouri, Christina1 aMichos, Evangelos1 aKatsampiris, Spyridon  uhttp://telematics.upatras.gr/telematics/publications/guideme-networked-application-indoor-orientation-and-guidance-0?language=el01915nas a2200157   4500008004100000245007300041210006900114520131000183100001801493700002101511700002201532700002401554700002201578700002601600856013101626       2020                        eng d00aGuideMe: A Networked Application for Indoor Orientation and Guidance0 aGuideMe A Networked Application for Indoor Orientation and Guida3 aToday’s indoor navigational systems are more and more in demand, commonly used for applications such as smart cities, robots and visually impaired people. As far as outdoor navigation is consider, the Global Positioning System (GPS) technology is still one of the most (if not the most) commonly used approaches. Even though it is still considered an ideal solution for navigating in outdoor areas, challenges and problems arise when GPS is considered for navigation inside buildings due to obstacles (e.g., shopping malls, hospitals, etc.) and because signals cannot be absorbed by the building walls. To tackle the aforementioned issue, other technologies have emerged aimed at indoor navigation, such as Wireless-Fidelity (Wi-Fi), Bluetooth and sensors. This paper’s contribution is towards indoor navigation and more specifically, it targets at designing and developing a tracking and navigation system aimed at people that experience difficulties in indoor orientation using a wearable device. The user takes direction from the wearable device for the indoor orientation through voice commands helping him to avoid obstacles. The central part of the system is a device that provides the ability to navigate and route by voice commands, based on the device's location and orientation capabilities.1 aBarri, Eirini1 aBouras, Christos1 aGkamas, Apostolos1 aKoulouri, Christina1 aMichos, Evangelos1 aKatsampiris, Spyridon  uhttp://telematics.upatras.gr/telematics/publications/guideme-networked-application-indoor-orientation-and-guidance?language=el01700nas a2200121   4500008004100000245005100041210005100092520125400143100002101397700002401418700002401442856011201466       2020                        eng d00aResource Allocation Mechanism for Massive MIMO0 aResource Allocation Mechanism for Massive MIMO3 aNowadays, mobile users need faster data speeds and more reliable service. The next generation of wireless networks 5G pledges to commit that, and much more. Multiple-Input, Multiple-Output (ΜΙΜΟ) technology in 5G networks is studied in this paper, with emphasis on the achieved performance in terms of achieved Bandwidth. Multi-antenna technologies, such as MIMO, are anticipated to play a key role in 5G systems, as they will have to handle much higher speeds than today's cellular networks and greater network traffic. Specifically, we will refer to Massive MIMO (Ma-MIMO) technology. In this paper, a resource allocation mechanism is proposed from the Base Station (BS) to the available antennas, using the Knapsack Problem (KP) algorithm. Our goal is to evaluate user access throughput to the antennas and to study the case where the BS allocates resources, according to the channel rate it receives from each User Equipment (UE). The scenario executed is about serving the maximum number of UE connected to the BS, in high quality services. Finally, we simulate the results in MATLAB, in order to be able to evaluate the Quality of Service (QoS) that is provided to the UE by the BS, with the resource allocation technique that is proposed.1 aBouras, Christos1 aKokkinos, Vasileios1 aKoulouri, Christina  uhttp://telematics.upatras.gr/telematics/publications/resource-allocation-mechanism-massive-mimo?language=el02032nas a2200157   4500008004100000245007800041210006900119520142200188100001801610700002101628700002201649700002401671700002201695700002601717856013101743       2020                        eng d00aText to Speech through Bluetooth for People with Special Needs Navigation0 aText to Speech through Bluetooth for People with Special Needs N3 aAs far as outdoor navigation is considered, the Global Positioning System (GPS) technology is still one of the most (if not the most) commonly used approaches. Even though it is still considered an ideal solution for navigating in outdoor areas, challenges and problems arise when GPS is considered for navigation inside buildings due to the fact that GPS signals cannot penetrate walls/ceilings (e.g., shopping malls, hospitals, etc.) and because signals can be absorbed by the building walls. This paper’s contribution is navigation system that assists people with special needs using an audio guidance system that incorporates input from a voice recognition system. The central part of the system is a device that is able to identify the position and orientation of the person that carries it and provide the ability to navigate and route by voice commands. The suggested voice synthesis system is used, so as to guide the user through obstacles in indoor locations. The information of the precise location and.orientation of the device is made available to the whole system, through the building’s network infrastructure, so that the user’s mobile phone, been connected to the same network and also to the user’s headset through BLE, is able to send audio commands. For the voice commands, Google Cloud Text-ToSpeech (TTS) will be used, supposed that an online connection is active on the user’s device.1 aBarri, Eirini1 aBouras, Christos1 aGkamas, Apostolos1 aKoulouri, Christina1 aMichos, Evangelos1 aKatsampiris, Spyridon  uhttp://telematics.upatras.gr/telematics/publications/text-speech-through-bluetooth-people-special-needs-navigation?language=el