Light Switch Research Articles

Affordable energy-saving switch control system for homes with disabled persons

The need for energy conservation has become increasingly urgent in today's world, especially as energy costs continue to rise and the demand for sustainable living grows. For persons with physical disabilities, simple tasks like turning light switches on and off can be challenging, resulting in higher energy usage, increased electricity bills, and increased physical strain. Existing solutions often prioritize energy efficiency but overlook affordability and accessibility, making them impractical for low-income households. To address these issues, this paper proposes an affordable automated energy-saving lighting switch control system using Arduino Uno, ultrasonic sensors for human presence detection, and a relay to control lighting. A person-counter mechanism ensures accurate operation based on room occupancy. Experimental results shows that the proposed system achieves 100% accuracy in detecting human presence in a room, effectively reducing energy consumption from 0.4 kWh to 0.2 kWh per day, which corresponds to 50% energy savings. Additionally, it is 42.41% less expensive than the most affordable system compared in the paper. These findings underscore the system’s potential to offer an affordable, accessible, and energy-efficient solution that enhances the convenience and comfort of disabled persons while contributing to energy conservation efforts.

A Queuing Model Based Rapid Evaluation Method for Automotive Control Design

This paper evaluates the ergonomics performance of automotive driving systems through a new computational model, aiming to enhance vehicle control design more cost-effectively than traditional experimental human factors research in the automotive field. Parameters such as spatial coordinates and control dimensions were measured for different driver interaction controls (e.g., hazard light switches, steering wheel buttons) across three typical passenger vehicles. These parameters were integrated into the QN-MHP-U to simulate driver operational behaviors and predict task performance. A computational method was introduced to assess the ergonomic scores of automotive control designs based on the modeling results. The QN-MHP-U provides a systematic and universally applicable solution for evaluating and comparing vehicle control designs within automotive driving systems. This allows automotive designers to assess and improve vehicle control designs from an ergonomic perspective more efficiently in terms of time and economic costs.

Electro-optically Modulated Nonlinear Metasurfaces.

Electrically reconfigurable nonlinear metasurfaces provide dynamic control over nonlinear phenomena such as second-harmonic generation (SHG), unlocking novel applications in signal processing, light switching, and sensing. Previous methods, like electric-field-induced SHG in plasmonic metasurfaces and Stark-tuned nonlinearities in quantum well metasurfaces, face limitations due to weak SHG responses from metals and mid-infrared constraints of quantum wells, respectively. Addressing the need for efficient SHG control in the visible and near-infrared ranges, we present a novel approach using the electro-optic (EO) effect to modulate SHG. By leveraging the exceptional EO and SHG properties of lithium niobate (LN), we integrate the EO effect with SHG within a metasurface framework for the first time. Our LN metasurface achieves an 11.3% modulation depth in SHG amplitude under a ±50 V alternating voltage. These results open new avenues for reconfigurable photonic applications. including tunable nonlinear light sources, quantum optics, and nonlinear information processing.

Lead-Free CsBi3I10 Thin-Film flexible photodetectors with enhanced performance for broad spectral response

By employing a hot spin-coating method, CsBi3I10 thin-film photodetector was fabricated onto flexible PET substrate. The resulting nontoxic photodetector demonstrated exceptional optoelectronic performance, featuring an Ilight/Idark ratio of 1.8 × 103, a responsivity of 18.3 mA/W and a detectivity of 2.95 × 108Jones. It also showed a broad spectral response and maintained consistent performance after 506 light switching cycles and 1000 bending cycles. The dynamic imaging capability of the device was further validated, illustrating its potential for diverse applications. This work pioneers the application of CsBi3I10 perovskite thin-film in flexible photodetectors, offering a green, stable and high-performance solution for next-generation optoelectronic devices.

Structural Aspects, Binding Interactions, Biological Activity of Co(II)‐ and Ni(II)‐N′‐(2‐fluorobenzoyl)benzo[d]thiazole‐2‐carbohydrazide Chelatess

ABSTRACTN′‐(2‐Fluorobenzoyl)benzo[d]thiazole‐2‐carbohydrazide (OFBBTCH, HL) and its chelates with Co(II) and Ni(II) have been synthesized and characterized by elemental analysis, liquid chromatography‐mass spectrometry (LC–MS), Fourier transform infrared spectroscopy (FT‐IR), ultra‐violet visible (UV–vis), nuclear magnetic resonance (NMR) spectroscopy, thermogravimetric analysis (TGA), and powder X‐ray diffraction. The conductance measurements reveal that the chelates are non‐electrolytic, and the spectral analysis indicates octahedral geometry of the chelates. The kinetic and thermodynamic parameters were obtained by Coats–Redfern relations, which shows positive Gibbs's free energy and negative entropy for both chelates. The equilibrium studies carried out by pH‐metry revealed the dissociation constant (pKa) of OFBBTCH as 8.13 and the formation of 1:1 and 1:2 Co(II)‐L and Ni(II)‐L complexes in solution. The CT‐DNA binding studies carried out by electron absorption, fluorescence quenching, steady state emissions and viscosity studies revealed hyperchromism and groove binding for HL and chelates. The Kb values calculated from electron absorption studies are 2.4 × 106, 4 × 106, and 9 × 106 M−1, from the fluorescence quenching studies Ksv values are 0.1722, 0.278, and 0.748 M−1, and Kapp values are 5.9 × 104, 1.3 × 105, and 2.9 × 105 M−1 for HL, Co(II)‐OFBBTCH and Ni(II)‐OFBBTCH, respectively. Bovine serum albumin (BSA) and human serum albumin (HSA) binding interactions were carried out by electron absorption and fluorescence quenching studies. The light switching properties of the chelates, the hydrolytic and oxidative cleavage of CT‐DNA, and the antioxidant properties were evaluated. Anti‐microbial studies carried out by pour plate method showed high activity for Ni(II)‐OFBBTCH chelate. Cytotoxicity of the compounds was performed for HeLa and MCF cell lines by MTT assay. Molecular docking studies revealed the docking of HL and Co(II)‐HL at the minor groove, and Ni(II)‐HL was docked at the major groove with hydrogen bonding.

Light switchable radical and non-radical periodate activation by Fe3O4/g-C3N4 for efficient organic contaminant elimination

Although the heterogeneous activation of periodate (PI) has recently garnered significant attention for organic pollutant degradation, regulating the non-radical and radical reaction pathways remains a challenge. Herein, a Z-scheme Fe3O4/g-C3N4 heterojunction (FCN) was developed to achieve controllable radical and non-radical PI activation using a light switch. In the dark, the interaction between FCN and PI gave rise to metastable surface-activated PI complexes (PI*) via the non-radical pathway, which served as the dominant reactive species for organic elimination. Upon light irradiation, FCN acted as an electron donor for PI activation via the radical pathway, forming iodate radicals (IO3•) for pollutant destruction. Consequently, the FCN/PI/VIS system achieved complete removal of acid orange 7 in 30 min, with a pseudo-first order reaction rate about 3.5 times higher than that of FCN/PI system. The involved reactive species were validated by scavenging tests, electron paramagnetic resonance (EPR) analysis, Raman spectra and electrochemical measurements. Moreover, the light switchable FCN-based PI activation system exhibited high recyclability and practicability for the treatment of various organic pollutants in water. This study provides new insights into the PI activation-mediated wastewater treatment processes.

Human activity recognition using binary sensors: A systematic review

Human activity recognition (HAR) is an emerging area of study and research field that explores the development of automated systems to identify and categorize human activities using data collected from various sensors. In the field of Human Activity Recognition (HAR), binary sensors offer a distinct approach by providing simpler on/off readings to indicate the presence of events such as door openings or light switch activations. Compared to other sensors used for HAR, binary sensors have several advantages, including lower cost, low power consumption, ease of installation, and privacy preservation. For instance, they can be effectively used in smart homes to detect when someone enters or leaves a room without user input. This study presents a systematic review of the state-of-the-art methods and techniques for HAR using binary sensors. We comprehensively consider five crucial aspects: data collection methods, preprocessing techniques, feature extraction and fusion strategies, classification algorithms, and evaluation metrics. Furthermore, we identify the gaps and limitations of the existing studies and provide directions for future research. This comprehensive and up-to-date review can serve as a valuable reference for researchers and practitioners in the field of HAR using binary sensors.

MEMS Micromirror Actuation Techniques: A Comprehensive Review of Trends, Innovations, and Future Prospects

Micromirrors have recently emerged as an essential component in optical scanning technology, attracting considerable attention from researchers. Their compact size and versatile capabilities, such as light steering, modulation, and switching, are leading them as potential alternatives to traditional bulky galvanometer scanners. The actuation of these mirrors is critical in determining their performance, as it contributes to factors such as response time, scanning angle, and power consumption. This article aims to provide a thorough exploration of the actuation techniques used to drive micromirrors, describing the fundamental operating principles. The four primary actuation modalities—electrostatic, electrothermal, electromagnetic, and piezoelectric—are thoroughly investigated. Each type of actuator’s operational principles, key advantages, and their limitations are discussed. Additionally, the discussion extends to hybrid micromirror designs that combine two types of actuation in a single device. A total of 208 closely related papers indexed in Web of Science were reviewed. The findings indicate ongoing advancements in the field, particularly in terms of size, controllability, and field of view, making micromirrors ideal candidates for applications in medical imaging, display projections, and optical communication. With a comprehensive overview of micromirror actuation strategies, this manuscript serves as a compelling resource for researchers and engineers aiming to utilize the appropriate type of micromirror in the field of optical scanning technology.

Phytic acid-based super antifreeze multifunctional conductive hydrogel for human motion monitoring and energy harvesting devices

Conductive hydrogels have broad application prospects in the field of self-powered sensors and energy harvesting devices due to their good electrical conductivity and flexibility. However, at low temperatures, conductive hydrogels are usually frozen, resulting in problems such as poor electrical conductivity and flexibility, which seriously hinder the application of these fields. To address these challenges, phytic acid (PA) was employed as the crosslinker and antifreezing agent in this study. Polyvinyl alcohol (PVA), 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS), chitosan (CS), and PA were used as raw materials to successfully synthesize PVA/AMPS/CS/PA (PACP) multifunctional conductive hydrogels with outstanding antifreeze and water retention properties (freezing point below −80 °C, 30-day water loss rate of 3.5%). In addition, PACP hydrogels exhibit exceptional electrical conductivity of up to 9.4 S/m, along with antibacterial and biocompatible properties, enabling their utilization as wearable sensors on human skin tissue. Notably, the PACP hydrogel-based triboelectric nanogenerator (PACP-TENG) excels in accurately monitoring human motion and powering small electronic devices, facilitating remote control of small light switches. The resulting open circuit voltage is as high as 314 V at 25 °C and about 110 V at low temperature. Therefore, PACP hydrogels with excellent properties are expected to expand their applications in these fields.

The Light Switch and the Dimmer: Qualitative Observations to Improve Diagnostic Lacrimal Irrigation

ABSTRACT Purpose To emphasise the importance of “soft” observations during lacrimal irrigation in diagnosing lacrimal outflow dysfunction and reporting outcomes of soft factors post-DCR. Methods A retrospective study of patients with ≤ 20% of regurgitation on lacrimal irrigation who underwent DCR surgery. A comparative analysis of percentage reflux of saline (RFX), initial mucus in reflux (IMR), patient-reported transit time of saline (PR-TTS), and resistance encountered (RES) during LS was performed. Validated TEARS score was used. Subjective success was defined as ≥ 2-point improvement in T subscale of TEARS score. Objective success, as a decrease in RFX, RES, PR-TTS and absence of IMR, post-operatively. Results From a total of 253 patients who underwent DCR surgery, 8 patients met the inclusion criteria. All patients were T4 (wiping >10× daily) indoors and outdoors. TEARS score improved after surgery with a mean reduction of T = 2.62, E = 1.63 and A = 1.35 (p < .05) with no significant change in R scores (p = .10). A mean reduction in RFX of 11.75 ± 6.74% and a median improvement of 1 point in PR-TTS and 2 point in RES was observed (p < .05). No significant changes of these parameters occurred in the contralateral side during this period. Subjective and objective success of DCR was 75% and 100%, respectively. Conclusions This study is the first to attempt to combine qualitative “soft” observations during lacrimal irrigation such as IMR, RES and PR-TTS for identifying nasolacrimal outflow dysfunction and reporting outcomes using these parameters of DCR in patients with epiphora and ≤ 20% of fluid regurgitation. These parameters were greater in the more symptomatic side and successfully improved after DCR, making them a valuable tool to reach a provisional diagnosis.

Factors Of Accidental Falls Among In Elderly Living Alone In Phetchaburi Province Thailand

This research was to study the factors of accidental falls among elderly living alone. The researcher conducted a mixed methods research (Mixed Methods Research) to study factors affecting the incidence of falls and falls in elderly people who live alone. The research results found that Factors that result in falls and falls in elderly people who live alone. Phetchaburi Province has a total of 5 main factors and 24 sub-factors, consisting of main physical factors. Sub-factors were eye disease (p = 0.001, β =1.063), osteoarthritis (p = 0.001, β = 0.955), urinary system intelligence (p = 0.001, β =1.588), frequently going to the bathroom at night (p = 0.001, β =1.236) Congenital disease (p = 0.001, β = 1.638) Regular hospital visits (p = 0.001, β = 1.494) Main behavioral factors Sub-factors include taking medicine to treat chronic diseases (p = 0.001, β = 2.959), using alcoholic beverages (p = 0.001, β = 4.014), not exercising (p = 0.001, β = 5.350), wearing comfortable shoes. Inappropriate (p = 0.001, β = 2.723) Inappropriate clothing (p = 0.001, β = 3.574) Main environmental factors Sub-factors: regularly using stairs (p = 0.001, β = 3.354), two-story house (p = 0.001, β = 4.571), split-level house (p =0.001, β = 2.296), light switch not nearby. mattress (p = 0.001, β =2.363) main economic and social factors The sub-factor was frequently attending social events (p = 0.001, β = 6.633), missing home visits from the health service unit (p = 0.001, β = 3.916). The main factor was caregiver. The sub-factor is living with offspring (p = 0.001, β = 6.019 ) and having to live alone (p =0.001, β = 1.002 ).

Controllable dual resonances of Fano and EIT in a graphene-loaded all-dielectric GaAs metasurface and its sensing and slow-light applications

Abstract Active nanophotonic metasurfaces have attracted considerable attention for their promise to develop compact, tunable optical metadevices with advanced functions. In this work, we theoretically demonstrated the dynamically controllable dual resonances of Fano and electromagnetically induced transparency (EIT) using a graphene-loaded all-dielectric metasurface with U-shaped gallium arsenide (GaAs) nanobars operating in the near-infrared region. The destructive interference between a subradiant mode (i.e., a dark mode) supported by two vertical GaAs bars and two radiative modes (i.e., two bright modes) supported by a horizontal GaAs nanobar gives rise to a Fano resonance and an EIT window with high transmission and a large quality factor (Q-factor) in the transmission spectrum. Importantly, the transmission amplitudes can be flexibly modulated by adjusting the graphene Fermi levels without rebuilding the nanostructures. This modulation results from the controllable light absorption by the loaded graphene monolayer due to its interband losses in the near-infrared spectrum. Furthermore, the peak wavelengths of the Fano resonance and EIT window with high Q-factors are highly sensitive to variations in the refractive index (RI) of the surrounding medium, giving the proposed metasurface a relatively good sensitivity of ~700 nm/RIU and a high figure of merit (FOM) of 280, making it an effective RI sensor. Additionally, the metasurface features an adjustable slow light effect, indicated by the adjusted group delay time ranging from 0.12 ps to 0.38 ps. Therefore, the metasurface system proposed in this work offers a viable platform for advanced multi-band optical sensing, low-loss slow light devices, switches, and potential applications in nonlinear optical fields.

Revealing Enhanced Optoelectronic Performance of Sb2Se3‐Based Self‐Sustaining Heterostructures with Bi2Se3 and ZnSe: A Dual Polarity Photo Response

AbstractThrough precise band engineering, Van der Waals heterostructures integration holds great promise for advancing high‐performance optoelectronic devices, especially photodetectors. This study presents self‐sustaining, dual‐polarity, high photo‐responsive heterostrutures (HS) photodetectors based on Sb2Se3, specifically Bi2Se3/Sb2Se3 and ZnSe/Sb2Se3. The Bi2Se3 (ZnSe) layer functions as a channel in a reconfigurable HS phototransistor configuration. These HS devices demonstrate a negative photoconductive response with bias‐modulated polarity switching of the photocurrent. The Bi2Se3/Sb2Se3 device exhibits a responsivity switch from −4 mA W−1 to 0.14 A W−1, while the ZnSe/Sb2Se3 device shows a substantially enhanced responsivity switch from ‐400 mA W−1 to 12 A W−1. This negative photo response results from a photoinduced carrier trapping mechanism at the interface of the channel layer and photosensitizer material. The bias modulation enables the switching from negative to positive responsivity. A comprehensive investigation of photoconductivity modulation provides a deeper understanding of the impact of the photogating effect and trap states under applied bias conditions. Ultrafast transient spectroscopy supports these findings, offering insights into the dynamics of charge carrier relaxation mechanisms and the trapping of photoexcited carriers in defect states, crucial for explaining the dual polarity photo response. These devices present significant advantages for switchable light imaging, optical communication, memory devices, convolution processing, and logic circuits.

QACDes: QoS-aware context-sensitive design of cyber-physical systems

There is a lot of confusion and ambiguity regarding the quantification of the Quality of Service (QoS) of a system, especially for cyber-physical systems (CPS) involved in automating or controlling the operations in built environments and critical urban infrastructures, such as office buildings, factories, transportation systems, smart cities, etc. In these cases, the QoS, as experienced by human users, depends on the context in which they (i.e., humans) interact with these systems. Traditionally, the QoS of a CPS has been defined in terms of absolute metrics. Such measures are unable to take into account the variations in performance due to contextual factors arising out of different kinds of human interactions. Further, the QoS of a CPS has typically been evaluated by comparing the performance of the actual, fully realized system with the given QoS constraints only after the actual system has been completely developed. In the case of faults in the design exposed by observed deviations from the QoS constraints due to unpredicted variations in the contextual factors, the system needs to be re-designed and re-developed from scratch. Due to the above-mentioned reason, the validation approach associated with the traditional QoS makes the design of CPS systems prohibitively expensive, impractical, as well as infeasible in numerous application areas, such as civil and engineering works, since it may not be possible to modify the system once developed beyond a certain extent. To that end, we propose a context-aware definition of QoS of a CPS which facilitates the design of robust systems as elaborated below. In this paper, we define QoS as a function of contextual factors. A CPS designed according to our QoS specifications would always satisfy the QoS irrespective of any possible changes in contextual factors resulting from many different human interactions that may occur during operation of the system. We also present QACDes - a novel framework that provides a formal mechanism for validating the design of a CPS with respect to the specified QoS constraints at the design phase as well as after the realization of the actual system. QACDes can validate any given CPS, irrespective of its application domain, against a QoS guarantee: (A) as early as even before the design phase by comparing the proposed model with a baseline model, or (B) after the realization of the actual system based on logs collected from running the actual system. We consider a lighting control system that manages the light switches - switching it on/off depending on contextual factors, such as the presence of occupants and time of the day. Using the lighting control system in a building as a use case, we analyze and demonstrate the effectiveness of our QoS definition as well as the QACDes framework against the performance metric measured in an actual fully-realized CPS.

Guiding Light with Programmable Wall Defects

AbstractExternal‐field controllable light‐guiding structures are critical in the field of optical circuits and optical integration, and many well‐designed solid‐state waveguides have good performance but are weakly controllable. Although there have been attempts at liquid light guiding, liquid‐filled waveguides cannot completely break the constraints of the solid structure, and in liquid crystal (LC), the smaller tuning angle of the optical soliton limits its further application. So designing a soft tunable light‐guiding structure becomes an urgent but challenging task. In this work, a novel electrically switchable light‐guiding structure with LC programmable wall defect is designed and verified. Wide‐angle recyclable switching of light guiding under an electric field and optical erasure and rewriting of the structure are realized, unleashing the potential of soft‐matter defect structures, and paving the way for soft optical devices and optoelectronic integration.

The light control resistance switch characteristics and conduction mechanism of BaTiO3/MoS2 structure

The light control resistance switch characteristics and conduction mechanism of BaTiO3/MoS2 structure

CVD-Grown Monolayer MoS2 and GaN Thin Film Heterostructure for a Self-Powered and Bidirectional Photodetector with an Extended Active Spectrum.

Photodetector technology has evolved significantly over the years with the emergence of new active materials. However, there remain trade-offs between spectral sensitivity, operating energy, and, more recently, an ability to harbor additional features such as persistent photoconductivity and bidirectional photocurrents for new emerging application areas such as switchable light imaging and filter-less color discrimination. Here, we demonstrate a self-powered bidirectional photodetector based on molybdenum disulfide/gallium nitride (MoS2/GaN) epitaxial heterostructure. This fabricated detector exhibits self-powered functionality and achieves detection in two discrete wavelength bands: ultraviolet and visible. Notably, it attains a peak responsivity of 631 mAW-1 at a bias of 0V. The device's response to illumination at these two wavelengths is governed by distinct mechanisms, activated under applied bias conditions, thereby inducing a reversal in the polarity of the photocurrent. This work underscores the feasibility of self-powered and bidirectional photocurrent detection but also opens new vistas for technological advancements for future optoelectronic, neuromorphic, and sensing applications.

42‐2: Self‐Scalable UV Blocking Artificial Iris Operated by Radially Controlled Crosslinking Density with Fast Switching Dynamics

In the anatomy of human eye, the role of iris is crucial since it controls the light level entering the eye and enhances the visibility. Here, we propose a soft contact lens type artificial iris actuated by eternal UV (ultra‐violet) light source, self‐regulating its effective aperture size by varying the crosslinking density of bio‐compatible polymer matrix doped with photochromic dye. For its self‐regulating characteristic, we cured HEMA‐based polymer matrix gradually from center to edge. Since the polymer matrix is polymerized by heat, we utilized NIR (near infra‐red) lamp and gradient grayscale patterned photomask for its gradual characteristic. Thereby, the crosslinking density of central position is higher compared to that of peripheral, causing slow switching dynamics. The gradient difference in switching dynamics leads to artificial iris gaining self‐regulation dynamics of effective aperture. The manufactured artificial iris shows advantage in blocking UV light, self‐regulating, and fast switching dynamics. The switching dynamics of artificial iris under bright and dim light adaptation are less than 50 seconds and 120 seconds, showing similar property with human iris.

Superior performance of ZnGaO solar-blind photodetectors by Implementing TFT structure and tunable ZnO cycle ratio

In this study, plasma enhanced atomic layer deposition was used to prepare ZnGaO thin films with different ZnO cycle ratios from 0 % to 50 %, which were employed to fabricate the MSM-type and TFT-type solar-blind photodetector. The properties of the films and the performance of the solar blind photodetector are greatly affected by the ZnO cycle ratio. Appropriate Zn doping content decreases the ratio of oxygen vacancies and Zn interstitials in Ga2O3, while excessive Zn doping degrades the quality of the film. Compared to MSM-type photodetector, an obviously improved performance of ZnGaO TFT-type photodetector has been observed due to its self-amplified photocurrent and the reduced dark current controlled by gate voltage. At a ZnO cycle ratio of 40 %, a superior performance of TFT-type solar-blind photodetector with an ultra-low dark current ∼4.5 × 10−13 A, an excellent light switching ratio ∼2.2 × 107, and an outstandingly high sensitivity ∼34.31 A/W has been obtained. These results demonstrate that the incorporation of Zn dopants can effectively modulate the performance of Ga2O3 TFT-type photodetector providing a great perspective for cost-effective and high-performance solar-blind PDs.

Opto-magnonic reservoir computing coupling nonlinear interfered spin wave and visible light switching

Physical reservoir computing is a promising approach to realize high-performance artificial intelligence systems utilizing physical devices. Recently, it has been experimentally found that nonlinear interfered spin wave multi-detection shows excellent performance for processing nonlinear time-series data due to its outstanding features: nonlinearity, short-term memory, and the ability to map in high dimensional space. However, said performance is considerably inferior to reservoir computing utilizing an optical circuit with a large volume. Herein, we develop reservoir computing with nonlinear interfered spin wave coupled with light switching, namely opto-magnonic reservoir computing. The spin wave was modulated through a crystal field transition that occurred in two different Fe3+ sites of Y3Fe5O12 by visible light switching, and it was found that the spin wave modulated by visible light switching dramatically reduced normalized mean square errors to 4.96 × 10−3, 0.163, and 3.66 × 10−5 for NARMA2, NARMA10, and second-order nonlinear dynamical equation tasks. Said excellent performance results from the strong nonlinearity caused by chaos and large memory capacity induced by reservoir states diversified by visible light switching.