One-Pot Hydrothermal-Derived NiS2 -CoMo2 S4 with Vertically Aligned Nanorods as a Binder-Free Electrode for Coin-Cell-Type Hybrid Supercapacitor

Transition bimetallic sulfides are exploited as high-capacity electrode materials in energy storage devices owing to their abundant electroactive sites and relatively high electrical conductivity compared with metal oxides. Here, an in situ conversion of metal ions into NiS₂ -CoMo₂ S₄ vertically aligned nanorod arrays on nickel foam (NS-CMS NRAs@NF) using a one-step hydrothermal technique to address the "dead-mass" limitation and multi-step preparation methods is reported. An in situ-converted NS-CMS NRAs obtained for 12 h of reaction time (NS-CMS NRAs-12 h@NF) delivers a superior areal capacity of 780 μAh cm^-2 to the other NS-CMS electrodes synthesized for 6 h (543.1 μAh cm^-2 ) and 18 h (636.7 μAh cm^-2 ) at 7 mA cm^-2 . A coin-cell-type hybrid supercapacitor (HSC) is also fabricated to unveil the practical adaptability of NS-CMS NRAs-12 h@NF electrode. Utilizing its structural and active material intriguing features, assembled coin-cell-type HSC achieves a high areal capacitance of 246.2 mF cm^-2 (5 mA cm^-2 ) along with maximum areal energy density (147 μWh cm^-2 ) and power density (21.3 mW cm^-2 ), respectively. Furthermore, the capability of coin-cell-type HSC in real-time applications is also inspected. This work promotes in situ deposition strategy to fabricate metal sulfide-based nanostructures for high-performance electrochemical capacitors.

Machine Learning Applied to Reference Signal-Less Detection of Motion Artifacts in Photoplethysmographic Signals: A Review

Machine learning algorithms have brought remarkable advancements in detecting motion artifacts (MAs) from the photoplethysmogram (PPG) with no measured or synthetic reference data. However, no study has provided a synthesis of these methods, let alone an in-depth discussion to aid in deciding which one is more suitable for a specific purpose. This narrative review examines the application of machine learning techniques for the reference signal-less detection of MAs in PPG signals. We did not consider articles introducing signal filtering or decomposition algorithms without previous identification of corrupted segments. Studies on MA-detecting approaches utilizing multiple channels and additional sensors such as accelerometers were also excluded. Despite its promising results, the literature on this topic shows several limitations and inconsistencies, particularly those regarding the model development and testing process and the measures used by authors to support the method's suitability for real-time applications. Moreover, there is a need for broader exploration and validation across different body parts and a standardized set of experiments specifically designed to test and validate MA detection approaches. It is essential to provide enough elements to enable researchers and developers to objectively assess the reliability and applicability of these methods and, therefore, obtain the most out of them.

Towards a Smart Environment: Optimization of WLAN Technologies to Enable Concurrent Smart Services

In this research paper, the spatial distributions of five different services-Voice over Internet Protocol (VoIP), Video Conferencing (VC), Hypertext Transfer Protocol (HTTP), and Electronic Mail-are investigated using three different approaches: circular, random, and uniform approaches. The amount of each service varies from one to another. In certain distinct settings, which are collectively referred to as mixed applications, a variety of services are activated and configured at predetermined percentages. These services run simultaneously. Furthermore, this paper has established a new algorithm to assess both the real-time and best-effort services of the various IEEE 802.11 technologies, describing the best networking architecture as either a Basic Service Set (BSS), an Extended Service Set (ESS), or an Independent Basic Service Set (IBSS). Due to this fact, the purpose of our research is to provide the user or client with an analysis that suggests a suitable technology and network configuration without wasting resources on unnecessary technologies or requiring a complete re-setup. In this context, this paper presents a network prioritization framework for enabling smart environments to determine an appropriate WLAN standard or a combination of standards that best supports a specific set of smart network applications in a specified environment. A network QoS modeling technique for smart services has been derived for assessing best-effort HTTP and FTP, and the real-time performance of VoIP and VC services enabled via IEEE 802.11 protocols in order to discover more optimal network architecture. A number of IEEE 802.11 technologies have been ranked by using the proposed network optimization technique with separate case studies for the circular, random, and uniform geographical distributions of smart services. The performance of the proposed framework is validated using a realistic smart environment simulation setting, considering both real-time and best-effort services as case studies with a range of metrics related to smart environments.