Radar-based millimeter-Wave sensing for accurate 3D Indoor Positioning - Potentials and Challenges

The 3D nature of modern smart applications has imposed significant 3D positioning accuracy requirements, especially in indoor environments. However, a major limitation of most existing indoor localization systems is their focus on estimating positions mainly in the horizontal plane, overlooking the crucial vertical dimension. This neglect presents considerable challenges in accurately determining the 3D position of devices such as drones and individuals across multiple floors of a building let alone the cm-level accuracy that might be required in many of these applications. To tackle this issue, millimeter-wave (mmWave) positioning systems have emerged as a promising technology offering high accuracy and robustness even in complex indoor environments. This paper aims to leverage the potential of mmWave radar technology to achieve precise ranging and angling measurements presenting a comprehensive methodology for evaluating the performance of mmWave sensors in terms of measurement precision while demonstrating the 3D positioning accuracy that can be achieved. The main challenges and the respective solutions associated with the use of mmWave sensors for indoor positioning are highlighted, providing valuable insights into their potentials and suitability for practical applications

3D millimeter-Wave Indoor Localization

The 3D nature of modern smart applications has imposed significant 3D positioning accuracy requirements, especially in indoor environments. However, a major limitation of most existing indoor localization systems is their focus on estimating positions mainly in the horizontal plane, overlooking the crucial vertical dimension. This neglect presents considerable challenges in accurately determining the 3D position of devices such as drones and individuals across multiple floors of a building let alone the cm-level accuracy that might be required in many of these applications. To tackle this issue, millimeter-wave (mmWave) positioning systems have emerged as a promising technology offering high accuracy and robustness even in complex indoor environments. This paper aims to leverage the potential of mmWave technology to achieve precise ranging and angling measurements presenting a comprehensive methodology for evaluating the performance of mmWave sensors in terms of measurement precision while demonstrating the 3D positioning accuracy that can be achieved. The main challenges and the respective solutions associated with the use of mmWave sensors for indoor positioning are highlighted, providing valuable insights into their potential and suitability for practical applications

A Survey of 3D Indoor Localization Systems and Technologies

Indoor localization has recently and significantly attracted the interest of the research community mainly due to the fact that Global Navigation Satellite Systems (GNSSs) typically fail in indoor environments. In the last couple of decades, there have been several works reported in the literature that attempt to tackle the indoor localization problem. However, most of this work is focused solely on two-dimensional (2D) localization, while very few papers consider three dimensions (3D). There is also a noticeable lack of survey papers focusing on 3D indoor localization; hence, in this paper, we aim to carry out a survey and provide a detailed critical review of the current state of the art concerning 3D indoor localization including geometric approaches such as angle of arrival (AoA), time of arrival (ToA), time difference of arrival (TDoA), fingerprinting approaches based on Received Signal Strength (RSS), Channel State Information (CSI), Magnetic Field (MF) and Fine Time Measurement (FTM), as well as fusion-based and hybrid-positioning techniques. We provide a variety of technologies, with a focus on wireless technologies that may be utilized for 3D indoor localization such as WiFi, Bluetooth, UWB, mmWave, visible light and sound-based technologies. We critically analyze the advantages and disadvantages of each approach/technology in 3D localization

CNN based Real-time Forest Fire Detection System for Low-power Embedded Devices

This paper proposes a system architecture that uses deep learning image processing techniques to automatically identify forest fires in real-time using neural network models for small UAV applications. Considering the strict power and payload constraints of small UAVs, the proposed model runs on a compact, lightweight Raspberry Pi4B (RPi4B) and its performance is comparable to the state-of-the-art metrics (accuracy and real-time response) while achieving significant reduction in CPU usage and power consumption. The proposed YOLOv5 optimization approach used in this paper includes: 1) Replacing the backbone network to ShuffleNetV2, 2) Pruning the Head and Neck network following the backbone baseline, 3) Sparse training to implement the model-pruning method, 4) Fine-tuning of the pruned network to recover the detection accuracy and 5) Hardware acceleration by overclocking the RPi4B to improve the inference speed of the algorithm. Experimental results of the proposed forest fire detection system show that the proposed algorithm compared to the state-of-the-art that run on RPi single board computer, achieves 50% higher inference speed (9 FPS), reduction in CPU usage and temperature by 35% and 25% respectively and 10% reduced power consumption while the accuracy (92.5%) is only compromised by 2%. Finally, it is worth noting that the accuracy of the proposed algorithm is not affected by deviations in the bird-eye view angle

Multicell Power Supplies for Improved Energy Efficiency in the Information and Communications Technology Infrastructures

The rapid growth of the Information and Communications Technology (ICT) sector requires additional infrastructure, such as more micro-datacenters and telecom stations, to support the higher internet speeds and low latency requirements of 5G networks. The increased power requirements of the new ICT technologies necessitate the proposal of new power supplies, in an attempt to support the increase in energy demand and running costs. This work provides an in-depth theoretical analysis on the losses of the individual stages of commercially available PSU and proposes a new multicell PSU, the buck PFC converter, which offers a higher overall efficiency at varying load levels. The theoretical results are verified using simulation results, via a PSIM Thermal Module, and using experimental data. The results indicate that multicell structures can improve the overall PSU efficiency by 1.2% at 50% rated power and more than 2.1% at full power. Finally, taking into consideration the economic implications of this study, it is shown that the proposed multicell structure may increase the PSU costs by 10.78%, but the payback period is in the order of just 3.3 years

Types of Corruption in Small and Micro Enterprises (SMEs) in Ibadan, Nigeria

Corruption is a phenomenon that manifests in various types and forms especially among operators of Small and Micro Enterprises (SMEs). Many actions of the operators which constitute corrupt practices often tend to be overlooked in spite of their grave consequences for the success SMEs in Nigeria. The fight against corruption in Nigeria is more concentrated in the formal sector. This study was, therefore, designed to investigate various forms in which corrupt practices are carried out among Small and Micro Enterprises in Ibadan, Nigeria. Business owners, their employees, apprentices and consumers constituted the study population. Primary data were collected using questionnaire administered on 200 business owners, 150 employees and 150 apprentices randomly chosen in five business districts in Ibadan; and the conduct of 10 in-depth interviews with purposively selected participants. Quantitative data were analysed at uni-variate level using simple percentages and frequencies while qualitative data were content analysed. Findings from the study revealed that corrupt practices were rampant among actors in SMEs and the common types of corrupt practices included stealing (60%), deception of customers (78.4%), tax evasion (62%), sale of fake products (76%), sale of expired products (65.2%), tampering with measurement scales (69.6%), bribery (82.4%), and poor service delivery (73%). The study concludes that the level of corruption in SMEs calls for concern and government should extend the fight against corruption to the informal sector in Nigeria

The effect of parental style on bullying and cyber bullying behaviors and the mediating role of peer attachment relationships: A longitudinal study

The purpose of the present study was the examination of the longitudinal effect of parental style on short-term changes in conventional and cyber forms of bullying/victimization, and the investigation of the mediating role of peer attachment relationships on this effect. The participants were 861 children and adolescents (52% girls, M  = 11.72 years) attending Cyprus public institutions. Students provided information during three measurement points. There was a six and a 12 week interval among the three measurement points, respectively. The findings of the study indicated that parenting seems to be a significant predictor of all forms of bullying/victimization, conventional and cyber, in early adolescents, even when accounting for bullying/victimization levels eighteen weeks back. More importantly, results showed that the effect of parental style on bullying forms was mediated by peer attachment relationships. Results are discussed in the light of theoretical and practical implications. [Abstract copyright: Copyright © 2018 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Will climate mitigation ambitions lead to carbon neutrality? An analysis of the local-level plans of 327 cities in the EU

Cities across the globe recognise their role in climate mitigation and are acting to reduce carbon emissions. Knowing whether cities set ambitious climate and energy targets is critical for determining their contribution towards the global 1.5 °C target, partly because it helps to identify areas where further action is necessary. This paper presents a comparative analysis of the mitigation targets of 327 European cities, as declared in their local climate plans. The sample encompasses over 25% of the EU population and includes cities of all sizes across all Member States, plus the UK. The study analyses whether the type of plan, city size, membership of climate networks, and its regional location are associated with different levels of mitigation ambition. Results reveal that 78% of the cities have a GHG emissions reduction target. However, with an average target of 47%, European cities are not on track to reach the Paris Agreement: they need to roughly double their ambitions and efforts. Some cities are ambitious, e.g. 25% of our sample (81) aim to reach carbon neutrality, with the earliest target date being 2020.90% of these cities are members of the Climate Alliance and 75% of the Covenant of Mayors. City size is the strongest predictor for carbon neutrality, whilst climate network(s) membership, combining adaptation and mitigation into a single strategy, and local motivation also play a role. The methods, data, results and analysis of this study can serve as a reference and baseline for tracking climate mitigation ambitions across European and global cities

Impact of the GATT and WTO on international trade

A dolgozat célja az Általános Kereskedelmi és Vámtarifa Egyezmény (General Agreement on Tariffs and Trade, GATT) és a Kereskedelmi Világszervezet (World Trade Organization, WTO) történelmi és gazdasági szempontból történő bemutatása. Emellett nagyító alá kerül e két intézmény elmúlt száz évre gyakorolt hatása, működésük eredményei, nehézségeik, sikereik és kudarcaik. A két intézmény bemutatása mellett természetesen szükség van néhány kérdés megválaszolására is: − Milyen tényezők álltak a GATT megszűnése és a WTO létrejötte hátterében? − Mire képes a WTO, amire a GATT előtte nem volt? − Milyen eredményeket értek el működésük alatt? S ami a legfontosabb: − Milyen hatással voltak az elmúlt évszázad világkereskedelmének fejlődésére?BSc/BAnemzetközi gazdálkodá