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A range of simulations for indoor and multicarrier scenarios show that fair coexistence between LAA and WiFi can be achieved, and that deployment of LAA can provide a boost in WiFi performance.
This paper presents a crowd sensing WiFi advisory system called WiFiScout, which helps smartphone users to find good quality WiFi hotspots.
Experimental results demonstrate that deep learning models with the intelligent fusion of pervasive WiFi and magnetic field data can effectively improve smartphone indoor localization compared to existing approaches based on WiFi only.
Beginning with two Wifi scan datasets collected on two large scale smartphone testbeds, we conduct case studies that show how smartphone channel scans can be used to (1) improve AP spectrum management, and (2) predict the impact of AP failure or overload.
This paper proposes an indoor navigation technique for a smartphone using WiFi.
First, through analyzing traces collected on 3785 smartphones for at least one month, we show that poor signal strength of both 3G and WiFi is routinely experienced by smartphone users, both spatially and temporally.
In this paper, we develop a navigation algorithm which fuses the WiFi received signal strength indicator (RSSI) and smartphone inertial sensor measurements.
In this paper, we propose an effective way to detect WiFi signal in wireless sensor networks and build signal attenuation model of WiFi signal to locate WiFi nodes.
In this work, we show, through experiments, how the radar degrades the WiFi throughput by lowering the signal to noise and interference ratio at the WiFi receiver.

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About Cr's problem?
5 answers
Cognitive Radio (CR) faces various challenges and issues. One significant problem is the security aspect, which has received limited attention despite the technology's dynamic nature and exposure to wireless networks. Additionally, the implementation of CR systems can be complex due to wireless channel difficulties introduced by fading, especially affecting the spectrum sensing process. Moreover, the National Service Framework for Coronary Heart Disease highlighted challenges in providing Cardiac Rehabilitation (CR), such as lack of funding, staff, space, and sessions, as well as issues with patient referral and attendance. Furthermore, the evolving nature of Software Engineering (SE) skills necessitates frequent updates to curriculum and teaching materials, emphasizing the need for better course guidance and recommendation systems in higher education.
How the channel can be estimated in irs-assisted mmWave multiuser MIMO system?
5 answers
Channel estimation in IRS-assisted mmWave multiuser MIMO systems can be achieved through various innovative approaches. One method involves leveraging deep learning for two-stage channel estimation, where the sparsity of the mmWave massive MIMO channel in the angular domain is exploited using a convolutional neural network, followed by channel reconstruction through a least squares problem. Another technique utilizes a machine learning-based channel predictor to estimate and predict user-IRS channels efficiently, reducing training pilot signals and enhancing data rates. Additionally, a peak detection-message passing algorithm can estimate angle, delay parameters, and channel gain by exploiting the array steering vector properties, particularly effective in low SNR scenarios. These methods showcase the diverse strategies available for accurate and efficient channel estimation in IRS-assisted mmWave multiuser MIMO systems.
How to calculate the inertia of grid forming, grid following and synchoronous generators ?
5 answers
To calculate the inertia of grid forming, grid following, and synchronous generators, various methods are proposed in the literature. One approach involves utilizing the extended Kalman filter (EKF) state estimation combined with a novel method to calculate the rate-of-change of frequency (RoCoF) for accurate inertia estimation in synchronous generators. Another technique involves estimating inertia based on ambient measurements and solving an optimization problem to fit these measurements to the synchronous machine classical model, which also helps estimate the equivalent damping of the system. Additionally, adaptive inertia calculation in virtual synchronous generators (VSG) can be achieved through disturbance-based approaches using voltage, frequency, and power measurements, leading to improved grid stability and battery system life. Furthermore, the implementation of photovoltaic virtual synchronous generators (PV-VSG) with maximum power point tracking (MPPT) offers a solution by providing virtual inertia and primary frequency modulation without energy storage devices.
How does the implementation of an industrial parameter monitoring system impact overall process efficiency and cost savings?
5 answers
The implementation of an industrial parameter monitoring system significantly impacts overall process efficiency and cost savings. By utilizing sensors to measure various parameters like temperature, gas levels, and production numbers, these systems enable real-time monitoring and management, enhancing safety and preventing accidents in hazardous environments. Incorporating IoT and wireless communication technologies like ZigBee, these systems facilitate remote monitoring, reducing human intervention, improving performance, and lowering operational costs. Moreover, the use of trend recognition algorithms in semiconductor production processes enhances data efficiency and accuracy, leading to early warning prompts for potential issues. Overall, these systems streamline operations, optimize resource utilization, and ensure uninterrupted processes, ultimately driving efficiency and cost-effectiveness in industrial settings.
How does spectrum scarcity impact the development and deployment of 6G networks?
5 answers
Spectrum scarcity significantly impacts the development and deployment of 6G networks. The transition to 6G, with its emphasis on ultra-reliable low-latency communication (URLLC) and massive connectivity, exacerbates the spectrum scarcity issue compared to 5G. Efficient spectrum management systems are crucial to address the increased demand for cellular services in 6G networks. Coordinating the allocation of radio frequency spectrum internationally and aligning innovative capabilities with technical parameters are essential to make informed decisions regarding spectrum resources for 6G networks. Moreover, the lack of global spectrum sharing and the presence of competition hinder the smooth development and deployment of 6G technologies. Therefore, overcoming spectrum scarcity through effective spectrum-sharing algorithms and international cooperation is vital for the successful evolution of 6G networks.
How does biometric authentication prevents unauthorized access?
5 answers
Biometric authentication prevents unauthorized access by utilizing advanced techniques such as multimodal biometrics, which combine features like fingerprints and face recognition to enhance security and accuracy. Additionally, biometric verification protocols have been developed to withstand malicious attackers and prevent biometric data leakage, offering security against various types of adversaries. Biometric technologies, including facial images, fingerprints, and iris patterns, are commonly used in the financial sector to ensure data security and access control, especially in online banking and self-service devices, reducing the risk of internal fraud and unauthorized access to sensitive information. Implementing safety mechanisms like fingerprint-based authentication systems for bank lockers ensures that only authenticated individuals have access, enhancing security in shared access environments.
How do wireless sensor networks differ from traditional wired sensor networks in terms of deployment and maintenance costs?
5 answers
Wireless sensor networks (WSNs) differ from traditional wired sensor networks in deployment and maintenance costs. WSNs offer advantages like greater flexibility, scalability, and the ability to monitor multiple locations simultaneously, leading to lower installation and maintenance costs compared to wired networks. However, a significant challenge for WSNs is their limited lifetime due to battery replacements, which can be costly and time-consuming. To address this, researchers have developed energy-efficient protocols, energy harvesting techniques, and the use of renewable energy sources to improve the lifetime of WSNs. These advancements aim to reduce energy consumption, enable sensors to recharge using ambient energy sources, and provide a reliable power supply through renewable sources like solar panels, ultimately impacting deployment and maintenance costs positively.
How do CRMs assist in delivering programs to a wider audience and enhancing data management?
5 answers
CRMs, such as Cremophor EL (CRM), play a crucial role in enhancing data management and expanding program delivery reach. CRMs like CRM, Triton X-100, and Tween-80 modify lipoproteins, affecting their mobility and density. In a similar vein, cognitive radios (CRs) utilize efficient medium access control mechanisms to dynamically allocate spectrum, enhancing network throughput and reducing power consumption. Moreover, process management tools aid in visualizing data flow, identifying bottlenecks, and fostering collaborative solutions, as seen in civil registration and vital statistics systems. Additionally, the Community Radiative Transfer Model (CRTM) provides accurate satellite simulations and Jacobian outputs, improving weather predictions and data analysis. By leveraging CRMs, CRs, and process management tools, organizations can streamline data processes, optimize resource allocation, and effectively deliver programs to a broader audience.
What are x ray protection in industry?
5 answers
X-ray protection in the industry is crucial for ensuring safety and compliance with regulations. Various methods and devices are employed for X-ray protection. One approach involves the use of a protector with a sandwich structure comprising plumbous rubber and basalt fiber cloth layers, along with safety features like anti-skidding ground nails and adjustable bases. Additionally, a protection device shields X-rays emitted from X-ray tubes by utilizing shielding plates and cylindrical closing plates to prevent human exposure to external radiation. Implementing wireless sensor networks equipped with X-ray radiation sensors and body infrared sensors can create a safety monitoring system in X-ray fields, enhancing staff safety and reducing accidents in industrial settings. These measures, along with adherence to radiation protection protocols and training, contribute to maintaining a safe working environment in industrial radiography.
Kalman filter is limited to Gaussian distribution?
4 answers
The Kalman filter's optimality relies on the Gaussian distribution assumption for process and observation model errors, which can lead to performance degradation or breakdown when this assumption is not met. To address this limitation, modifications like the Gaussian integral filter (GIF) have been proposed to handle non-Gaussian noises effectively, such as Laplace distributions for process noise in tracking applications. Additionally, robust Gaussian approximate filters and smoothers have been developed to handle heavy-tailed measurement noise and unknown latency probabilities in nonlinear systems, providing more accurate estimations despite the non-Gaussian characteristics of real-world measurements. These advancements showcase efforts to extend the applicability of filtering techniques beyond Gaussian assumptions to enhance performance in diverse real-world scenarios.
Why lithium ion battery state of charge estimation is important?
5 answers
Estimating the state of charge (SOC) of lithium-ion batteries is crucial due to its impact on battery performance and longevity. Accurate SOC estimation is essential for calibrating the remaining charge in electric vehicles, ensuring efficient energy management, and preventing overcharging or deep discharging, which can damage the battery. Various methods like adaptive boosting algorithms, extended Kalman filters, and unscented Kalman filters are proposed to enhance SOC estimation accuracy. Reliable SOC estimation also aids in monitoring cell inconsistency, improving battery pack service life, and enhancing safety performance. Real-time SOC estimation is vital for battery management systems in electric locomotives and grid applications to ensure safe operation and maximize battery life.