Lead-free PEA₂SnI₄-based perovskite LEDs are successfully inkjet-printed on rigid and flexible substrates. Red-emitting devices (λ_max = 633 nm) exhibit, under ambient conditions, a maximum external quantum efficiency (EQE_max) of 1% with a related brightness of 30 cd/m² at 10 mA/cm².

In this work, we report the digital and analog resistive-switching (RS) characteristics in a memristor based on silicon nanocrystals (Si-NCs) integrated into a complementary metal-oxide-semiconductor (MOS) structure. Si-NCs with a diameter of 5.48 ± 1.24 nm embedded in a SiO₂/Si-NCs/SiO₂ multilayer structure acts as an RS layer. These devices exhibit bipolar RS with an intermediate resistance step during SET and RESET processes, which is believed to lie in the Si-NCs layer acting as charge-trapping nodes. The endurance studies of about 70 DC cycles indicate an ON/OFF ratio of ~10⁶ and a retention time larger than 10⁴ s. Long-term potentiation (LTP, −2 V) and long-term depression (LTD, +4 V) are obtained by applying consecutive identical pulse voltages of 150 ms duration. The current value gradually increases/decreases (LTP/LTD) as the pulse number increases. Three consecutive identical pulses of −2 V/150 ms (LTP) separated by 5 and 15 min show that the last current value obtained at the end of each pulse train is kept, confirming an analog RS behavior. These characteristics provide a possible way to mimic biological synapse functions for applications in neuromorphic computing in Si-NCs-based CMOS structures.

The objective of this study is to find out if it is possible to achieve the circadian levels recommended by different published lighting guidelines using different color configurations in a text editor. By measuring 25 monitors of different sizes, the circadian impact is evaluated at a standard distance using two different parameters: Circadian Stimulus and Melanopic Equivalent Daylight Illuminance. After analyzing the results, we see that during the night Circadian Stimulus is, in most cases, within the recommended range, but the same is not true for Melanopic Equivalent Daylight Illuminance. In addition, the circadian impact of the f.lux software has been analyzed and compared with two different cases of color configurations in a text editor.

The continuous expansion of the Internet of Things (IoT) has intensified the need to evaluate and guarantee the quality of entropy sources used in random number generation, an essential element in securing communications used in IoT ecosystems. This work presents an automated and web-based framework designed to execute and analyze the results of statistical tests defined in the NIST SP 800-22 standard, enabling systematic assessment of entropy sources and random numbers generators in IoT devices and environments. The proposed system integrates a Python-based backend built upon an optimized implementation of the original NIST suite, along with an intuitive web interface that facilitates configuration, monitoring, and parallel execution of tests through Representational State Transfer (REST) endpoints. Session management based on Redis ensures reliable and concurrent operation of multiple users or devices while maintaining isolation and data integrity. To demonstrate its applicability, an emulated IoT ecosystem was implemented in which multiple virtual devices periodically and asynchronously request real-time validation of their local random numbers generators. The obtained results confirm the system’s capability to detect deficiencies in pseudo random generators and validate true random number sources, highlighting its potential as a diagnostic and verification tool for distributed IoT security systems. The tool developed in this work is fully accessible to the public, allowing researchers, engineers, and practitioners to evaluate random number generators without requiring specialized hardware or proprietary software.