Light-emitting Diode Bulbs Research Articles

Advanced Home Automation Using Light Fidelity

Light Fidelity or Li-Fi is an emerging technology that uses the visible light spectrum for communication. Home automation is one of the very useful ways to control various electronic devices used in a home for our day to day activities. This paper proposes the use of Li-Fi technology, comprising light-emitting diode (LED) bulbs, as means of connectivity. Data is sent through light spectrum on an optical wireless medium as signal propagation. This idea can be implemented as an android application connected to the cloud. All the devices in any home can be monitored and controlled using this app installed in a mobile phone. A user can change the state of any device (ON/OFF) with this app. Changes are made in the cloud, and a message is sent as a binary sequence to the hardware connected to the light source. After translation, the identity of the device that needs to be controlled is obtained along with the message to toggle it between the ON and OFF states. This message is sent across using visible light communication in a secure way as the data remains within the limits of the four walls. Hardware on the receiving end senses the blinking light source, and translates the blinks into a binary sequence thus obtaining the original message. Then the device performs the necessary action and updates the cloud after completion. This is further reflected on the android application of the user's phone. Attackers cannot break into this system easily, as the device identity and the light source is required to manipulate it.

Implications of White Light-Emitting Diode-Based Photoirradiation on Green Synthesis of Silver Nanoparticles by Methanol- and Aqueous-Based Extracts of Bergenia ciliata Leaves.

Bergenia ciliata (BC) is a perennial herb that is frequently used as a traditional medicine. Its leaves and rhizomes are reported to have significant antioxidant, metal-reducing, and chelating properties. Although the rhizomes have the potential to synthesize silver nanoparticles (AgNPs), the leaves are yet to be studied for the green synthesis of metal nanoparticles. Likewise, photoirradiation also plays a significant role in the green synthesis of metal nanoparticles. In the current study, we intended to demonstrate the implications of photoirradiation by white light-emitting diode (LED) on the aqueous and methanol extracts (AE and ME, respectively) of BC leaf-mediated green synthesis of AgNPs. In this regard, the AgNP synthesis of the two extracts was performed in the dark and under 250-lumen (lm) and 825 lm LED bulbs. The physicochemical characterization of the synthesized nanoparticles was also performed, wherein percent nanoparticles yield, morphology of the nanoparticles, shape, size, percent elemental composition, crystallinity, and nanoparticle stability were studied. The nanoparticle-synthesizing potential of the two extracts contradicted significantly in the presence and absence of light, while the AE produced a significantly high number of nanoparticles in the dark (17.26%), and increasing light intensities only attenuated the nanoparticle synthesis, whereas ME synthesized comparatively negligible silver nanoparticles in the dark (1.23%). However, increasing light intensities significantly enhanced the number of nanoparticles synthesized in 825 lms (7.41%). The GCMS analysis further gave a comparative insight into the phytochemical composition of both extracts, wherein catechol and pyrogallol were identified as major reducing agents for nanoparticle synthesis. The influence of light intensities on the physiochemical characterization of AgNPs was predominant. While the size of both the AE- and ME-mediated AgNPs increased considerably (20-50 nm diameter) with increasing light intensities, the percent of silver atoms decreased significantly with increasing light intensities in both the AE- and ME-mediated AgNPs with ranges of 13-18% and 14-24%, respectively. The nanoparticle stability studies suggested that both the AE- and ME-mediated AgNPs were stable for up to 15 days when stored at 4 °C. The stability of both nanoparticles was attributed to the presence of a wide range of phytochemicals. In conclusion, the AE of BC leaves was reported to have significantly higher AgNP-synthesizing potential as compared to the ME. However, AE-mediated AgNP synthesis is attenuated by photoirradiation, whereas ME-mediated AgNP synthesis is enhanced by photoirradiation. The photoirradiation by white LED light increases the size of the AgNPs, while the percent silver composition declines, irrespective of the extract type. Both extracts, however, have nanoparticle stabilizing potential, thereby producing stable nanoparticles.

Supramolecular Sequential Light-Harvesting Systems for Constructing White LED Device and Latent Fingerprint Imaging.

The fabrication of supramolecular light-harvesting systems (LHS) with sequential energy transfer is of significance in utilizing light energy. In this study, we report the non-covalent self-assembly of a sequential LHS by pillar[5]arene-based host-guest interaction in water and its applications in white light-emitting diode (LED) device and latent fingerprint imaging. The host-guest complex WP5 G self-assembles into nanoparticles in water and shows enhanced aggregation-induced emission (AIE) effect. The nanoparticles can be further used to construct sequential LHS with fluorescent dyes 4,7-di(2-thienyl)-benzo[2,1,3]thiadiazole (DBT) and sulforhodamine 101 (SR101). Impressively, the system shows white-light emission when the molar ratio of WP5 G/DBT/SR101 is 1100/2/16. The material can be coated on a LED bulb to achieve white-light emission. In addition, the sequential LHS exhibit multicolor fluorescence including red emission, which have been successfully applied to high-resolution imaging of latent fingerprints. Therefore, we demonstrated a general strategy for the construction of sequential LHS in water based on macrocyclic host-guest interaction and explored its multi-functional applications in white-light LED device and imaging of latent fingerprints, which will promote future development and application of supramolecular LHSs.

Wireless End to End Image Transmission System using Li-Fi Technology

The first and most important objective of this project is to convey the image through the utilization of a light-emitting diode (LED). The innovative technique known as visible light communication (VLC) holds enormous promise for the implementation of high-speed, large-capacity, short-range wireless data transmission. It is gaining popularity on account of the growing use of solid-state lighting systems. Additionally, LED lights change frequency at a rate that is substantially faster than what the human eye is able to perceive. This is in addition to the fact that radio waves have a higher repetition rate than LED lights, which results in significantly greater speed than Wi-Fi. This work suggests a real-time image broadcast system prototype. Light-emitting diode (LED) lights are used in the prototype since they are widely available and reasonably priced. The scope of the work encompasses the possibility of making information and communication accessible through the utilization of LED bulbs in a manner that may be implemented in a variety of situations, such as homes, offices, organizations, and corporations. If the LED sources are positioned correctly and concentration effects are increased, it is feasible to obtain a real-time image with a maximum distance of two feet, according to the testing results. In addition to being made to last, the LI-FI (Light Fidelity) light source features a broad variety of digital settings that can be adjusted, and it is simple to operate as a result of its efficient design

Nano PDA@Tur-Modified Piezoelectric Sensors for Enhanced Sensitivity and Energy Harvesting.

Tourmaline is known for its natural negative ion effect and far-infrared radiation function, which promote human blood circulation, relieve pain, regulate the endocrine system, and enhance immunity and other functions. These functions motivate the use of this material for enhanced sensitivity of wearable sensors. In this work, taking advantage of the unique multifunctions of tourmaline nanoparticles (Tur), highly boosted piezoelectricity was achieved by incorporating polydopamine (PDA)-modified Tur in PVDF. The PDA@Tur nanofillers not only effectively increased the β-phase content of PVDF but also played a major role in significantly enhancing piezoelectricity, wettability, elasticity, air permeability, and stability of the piezoelectric sensors. Especially, the maximum output voltage of the fiber membrane with 0.5 wt % PDA@Tur reached 31.0 V, being 4 times that of the output voltage of the pure PVDF fiber membrane. Meanwhile, the sensitivity reached 0.7011 V/kPa at 1-10 N, which was 3.6 times that of pure PVDF film (0.196 V/kPa). The power intensity reached 8 μW/cm2, being 5.55 times that of the pristine PVDF PENG (1.44 μW/cm2), and the piezoelectric coefficient from d33 m/PFM is 5.5 pC/N, higher than that of pristine PVDF PENG (3.1 pC/N). Output signal graphs corresponding to flapping, finger, knee, and elbow movements were detected. The response/recovery time of the sensor device was 24/19 ms. The piezoelectric nanogenerator (PENG) was capable of charging multiple capacitors to 2 V within a short time and lighting up 15 light-emitting diodes bulbs (LEDs) simultaneously with a single beat. In addition, a 4 × 4 row-column multiplexed sensor array was made of PENGs, which showed distinct responses to different stress areas in different sensor modules. This study demonstrated high-performance PDA@Tur PVDF-based PENG being capable of energy harvesting and sensing, providing a guideline for the design and buildup of wearable self-powered devices in healthcare and human-computer interaction.

Clean energy for a sustainable future: Analysis of a PV system and LED bulbs in a hotel

Scholars are increasingly prioritising sustainability as the driving force behind their research efforts, and many businesses are placing the customer at the centre of their agendas. Hospitality facilities, such as hotels, are also making concerted efforts to mitigate climate change. The present study proposed a sustainability analysis of the installation of a photovoltaic (PV) system and the replacement of conventional lighting with light emitting diode (LED) bulbs in a hotel, considering economic, environmental and social sustainability dimensions.The results showed that NPV varied between 967 and 3624 €/kW for the PV system, with a 100 % probability of achieving a positive NPV in a high market scenario and a 79–84 % probability of the same in a low market scenario. Concerning energy efficiency, the adoption of LED bulbs determined a NPV in the range of 105–216 €/bulb. These figures were highly dependent on the percentage of self-consumed energy and the purchase price of electricity. Environmental analyses indicated that the installation of a PV system could lead to an emissions reduction of 422 gCO2eq/kWh, translating to 61 tCO2eq/year. In addition, social analyses underscored the significance of renewable installations and energy-efficiency interventions to support the ecological transition. However, consumer choices within hotels did not consistently align with sustainable models. Notably, a green premium of 13.2 €/day was recognised for hotels using renewable systems, and 8.3 €/day for those using smart lighting. The results advocate for a pragmatic sustainability model that sees green investments enhancing a hotel's sustainability. However, a shift in consumer attitudes is necessary to fully realise this potential.

Reducing energy consumption in a factory and providing an upgraded energy system to improve energy performance

The industrial sector is a major energy consumer worldwide. Much of this consumption is due to air conditioning systems. In regions with extreme temperature conditions, the electricity consumption of these air conditioning systems increases significantly. This study was carried out with the objective of calculating the total energy consumption of the factory and identifying methods to decrease it. Furthermore, an enhanced energy system is suggested to lower energy consumption. This study was carried out with the objective of calculating the total energy consumption of the factory and identifying methods to decrease it. Furthermore, an enhanced energy system is suggested to lower energy consumption. It is also evident that the cooling load decreases by 21,661 kWh when thermal insulation is applied to the walls. Utilizing double-glazed windows for the skylight roof can lead to a reduction in the cooling load by 822 kWh. Additionally, the use of Light-Emitting Diode (LED) bulb lamps in the factory can further decrease the cooling load by up to 14,717 kWh.

Fabrication and Development of a Biomass-Based Supercapacitor with Enhanced Energy Storage Characteristics

In this work, a raw carbon waste parali biomass is collected to develop a supercapacitor. The activated carbon developed is characterized using X-ray diffraction (XRD), Field effect scanning electron microscope (FESEM), Energy dispersive spectroscope (EDS), and Brunauer–Emmett–Teller (BET) analyses. The porous and crystalline activated carbon achieved a remarkably high carbonaceous value of 99.85% carbon from 35.71% in raw state. The specific surface area obtained is 151.42 m2 g−1 and the porosity (average pore diameter) is 2–10 nm of the optimized activated carbon. The activated carbon is explored as electrode material for supercapacitor in aqueous electrolyte and the specific capacitance was found to be a maximum of 247 F g−1 at 1.2 A g−1 to a stable value of 180 F g−1 at 10 A g−1. The symmetrical supercapacitor device, featuring electrodes composed of carbon material, attains an impressive energy density of 54 Wh kg−1 along with outstanding coulombic efficiency and stability. The laboratory prototype supercapacitor has successfully powered consumer electronics, such as a DC (direct current) motor for 12.5 min and an LED (Light emitting diode) bulb for 14 min, on a single charge in each case.

LIFETIME PREDICTION OF SINGLE-STAGE LED DRIVER CIRCUIT USING BAYESIAN BELIEF NETWORK

In light-emitting diode (LED) lighting, the driver commands the lifetime and the LED bulb. It is essential to predict the driver's lifetime during its design stage. This paper proposes a viable method to predict the lifetime of the LED driver based on its failure rate. A novel single-ended primary inductor converter (SEPIC) integrated parallel ripple cancellation circuit (PRC) topology of 30 W is considered to estimate the lifetime of the driver circuit. The failure rate model is regarded as a base to predict the lifetime of LED drivers using Bayesian belief network (BBN) analysis. The weakest links are the prime components to estimate the lifetime, and they are active devices and capacitors employed in the driver circuit. The output capacitor is considered a degree of importance as per the existing literature, and the proposed course has been designed without using any electrolytic capacitor (EC) to enhance the reliability of the driver circuit. This approach ensures an effective way to access the mean time to failure (MTTF) or the lifetime of the LED driver in a lucrative manner.

Construction of activated-CNT/carbon composite aerogel for supercapacitor electrode with ultra high cycle stability

Double layer supercapacitors are widely used for energy storage devices due to their excellent characteristics such as high stability and good cycling performance. In this work, a novel carbon aerogel doped with activated short multi-walled carbon nanotube (CA/AMWCNT composite aerogel) was constructed by sol-gel and carbonization process. The effects of the activated short multi-walled carbon nanotube (AMWCNT) addition amount on the microstructure and electrochemical properties of the composite aerogels were investigated. The composite aerogels with appropriate AMWCNT addition amount exhibited improved specific surface area, pore diameter and pore volume. In particular, the composite aerogel CA/AMWCNT-2.5, with higher specific surface area (640 m2 g−1) and pore volume (1.985 cm3 g−1), exhibited improved electrochemical performance with the equivalent series resistance and specific capacitance at a current density of 1 A g−1 being 0.36 Ω and 115.11 F g−1, respectively. Moreover, the composite aerogel CA/AMWCNT-2.5 electrode showed excellent cycle stability, with the retention rate maintaining 99.9 % even after 10,000 cycles, and three prepared symmetrical supercapacitors could supply power for a light emitting diode bulb for a long time. This work provides a new strategy for developing electric double layer supercapacitors with ultra high cycling stability, and the obtained CA/AMWCNT composite aerogels will have promising applications in the field of energy storage devices that require a long service lifetime.

Lithium storage of SnP2O7 anode coated by N-doped carbon and anchored on P-doped carbon framework

N-doped carbon-coated SnP2O7 anodes anchored on P-doped carbon framework (SPO/C-P@C-N) have been successfully synthesized via a novel and environmentally friendly method, using a green raw material of phytic acid as phosphorus and carbon sources, and dimethylimidazole as the second carbon source and nitrogen source. N-doped carbon coating and P-doped carbon framework inhibit the volume shrinkage and expansion, improve the electronic conductivity and diffusion coefficient of Li+ ions as well as capacitive contribution ratio, reduce the charge transfer resistance and the particle size, and then enhance the electrochemical performance of SPO/C-P@C-N. SPO/C-P@C-N-1.2 with the carbon content of 18.5 wt% exhibits excellent electrochemical performance. The discharge specific capacity is 416.6 mAh/g at 0.5 A/g after 200 cycles. 234.3 mAh/g is kept at 2 A/g for the 1000th cycle. In addition, the discharge specific capacity of the LiNi0.5Mn1.5O4//SPO/C-P@C-N-1.2 full cell is 206.6 mAh/g for the 200th cycle at 0.5C in 1.4–4.4 V. The full cell can power green, red, blue, and orange light-emitting diode (LED) bulbs, as well as LED small light strings and heart-shaped circuit boards. It is the first report on SnP2O7 successfully applied to full cells, demonstrating the potential application.

Carbon-coated SnOx anchored on phosphorus-doped carbon framework as high performance anode of lithium-ion batteries

SnO2 has been recognized as one of the most potential anodes of lithium-ion batteries due to its high theoretical specific capacity, low cost, simple synthetic method, and environmental friendliness. However, the application of SnO2 is hindered owing to its huge volume expansion (∼300 %) and poor electronic conductivity. In this work, carbon-coated SnOx containing some SnO anchored on the phosphorus-doped carbon framework (SnOx/C–P@C) has been fabricated via a novel, simple and green precipitation route using phytic acid as the complexing agent, carbon and phosphorus sources, and glucose as the second carbon source. Phosphorus-doped carbon framework in situ forms via calcining phytic acid at a high temperature. Phosphorus doping can further enhance the electronic conductivity of carbon. The carbon framework can provide sufficient buffer space to make the SnOx particles have good dispersion. The carbon layer from glucose can prevent the direct contact between SnOx and the electrolyte to decrease the side reactions and then reinforce the structure of SnOx/C–P@C. The synergistic effect of the double carbon effectively controls the volume expansion, enhances the electronic conductivity and diffusion coefficient of Li+ ions as well as capacitive contribution ratio, and reduces the charge transfer resistance of SnOx/C–P@C. The SnOx/C–P@C-0.5 sample with the carbon content of 25.8 wt% exhibits outstanding electrochemical performance. At 0.1 A g−1, the discharge specific capacity of 776.2 mAh g−1 can be reached after 100 cycles. At 0.5 A g−1, 555.5 mAh g−1 is still delivered after 200 cycles. Moreover, the sample shows good potential practical applications in the LiNi0.5Mn1.5O4//SnOx/C–P@C-0.5 full cell. 687.9, 597.1, 510.1, 434.8 and 595.6 mAh g−1 are retained for the full cell at 0.1, 0.2, 0.5, 1 and 0.1 C, respectively. The full cell cycling for 200 cycles at 0.5 C can still light up the light-emitting diode (LED) bulbs.

Indoor tracking for smart hospital by a hybrid visible light positioning system

<p class="Abstract">Modern hospital operations and management, i.e., smart hospitals, require pervasive system-wide wireless communication and positioning capabilities. Unfortunately, this cannot be entirely facilitated by existing radio frequency (RF) wireless technologies due to interference concerns in hospitals. We design and implemented a novel hybrid RF-free wireless tracking system utilizing combined visible light communication (VLC) and positioning (VLP), and powerline communication (PLC) technologies to enable future smart hospital operations. This VLC/VLP/PLC tracking system consists of host optical transceivers embedded in light-emitting diode (LED) bulbs and user-end photodetector (PD) optical tags, as well as backbone powerline interface, to form a ubiquitous wireless tracking and communication network connecting all people and equipment throughout all hospital buildings. The new indoor optical-based tracking system was validated via simulation and experiments. Being embedded into the existing LED lighting infrastructure, this hybrid VLC/VLP/PLC tracking system technology is accurate, ultralow cost and environment friendly. Smart hospitals will lead to efficient and affordable healthcare, a revolutionary solution in the human society.</p>

Image and Text Transmission using Li-Fi Technology

This research paper focuses on the use of LiFi (Light Fidelity) technology for the transmission of image and text data. LiFi technology is an emerging technology that uses visible light communication (VLC) for data transmission, providing a high-speed and secure wireless communication system. In this project, a LiFi system is developed using an LED (Light Emitting Diode) bulb and a photodiode receiver to transmit and receive data. The system is tested for its ability to transmit image and text data at a high speed and with minimal interference. The results show that LiFi technology can provide a viable alternative to traditional wireless communication systems for certain applications, such as indoor communication and data transfer, where security and high-speed data transfer are essential. Overall, this research demonstrates the potential of LiFi technology as a reliable and secure means of wireless data transmission

Light emitting diode bulb aspiration in children: a rare entity

Foreign body aspiration is a life threatening emergency in children. Different types of foreign bodies are aspirated and reported in literature but light emitting diode (LED) bulb is an unusual cause of foreign body aspiration. Rigid bronchoscopy is gold standard for treatment of foreign body aspiration. We wish to present a case of 9 years old male child with LED bulb aspiration which was retrieved with rigid bronchoscopy.

Effect of Electrolytic Cations on a 3D Cd-MOF for Supercapacitive Electrodes

A cadmium-based metal-organic framework (Cd-MOF) is synthesized in a facile manner at ambient temperature by an easy slow diffusion process. The three-dimensional (3D) structure of Cd-MOF is authenticated by single-crystal X-ray diffraction studies and exhibits a cuboid-shaped morphology with an average edge length of ∼1.13 μm. The prepared Cd-MOF was found to be electroactive in nature, which resulted in a specific capacitance of 647 F g-1 at 4 A g-1 by maintaining a retention of ∼78% over 10,000 successive cycles in the absence of any binder. Further, to distinguish the efficiency of Cd-MOF electrodes, different electrolytes (NaOH, KOH, and LiOH) were explored, wherein NaOH revealed a higher capacitive response due to its combined effect of ionic and hydrated ionic radii. To investigate the practical applicability, an asymmetric supercapacitor (ASC) device is fabricated by employing Cd-MOF as the positive electrode and activated carbon (AC) as the negative electrode, enabling it to light a commercial light-emitting diode (LED) bulb (∼1.8 V). The as-fabricated ASC device delivers comparable energy density and power density.

From sodium-vapour to LEDs: how an outdoor lighting retrofit affects insects in Singapore

Abstract In the Anthropocene, the planet is warming and global biodiversity, including of insects, is being lost at an unprecedented rate. One largely urban sustainability solution, shifting to energy-efficient, light-emitting diode (LED) bulbs on outdoor lighting, has impacts on insects that are inadequately understood, especially in the tropics and brightly lit cities. Working in Singapore—a highly urbanised and light-polluted tropical city-state—we performed a field experiment to test the hypothesis that newly retrofitted LED lights are more attractive (i.e., detrimental) to insects compared to the high-pressure sodium (HPS) lamps they replace. Instead, our sticky traps, which we mounted on both light types, caught statistically equal numbers of arthropods (individuals and families). Traps on LED lamps also attracted proportionally fewer dipterans and more hemipterans and hymenopterans, but these effects were site-specific. Overall, we found no support for our hypothesis—our findings may reflect differential emissions of ultraviolet wavelengths by both light types and/or the possibility that urban insect assemblages with historic exposure to light pollution may not respond as expected to the retrofit. We caution against extrapolating findings from impact studies to untested contexts and highlight the need for (1) more studies in the rapidly urbanising tropics and (2) field tests of the effectiveness of measures to limit any negative ecological impacts of LED lighting, including other lethal and sublethal effects that we did not assess. We also discuss possible implications for ecosystem services and insect conservation.

Co-containing metal-organic framework for high-performance asymmetric supercapacitors with functionalized reduced graphene oxide.

Nowadays, supercapacitors are the most coveted eco-friendly and sustainable next-generation energy storage devices. In this regard, developing supercapacitors with high energy density and power density has always been a challenge for researchers. Herein, we have exploited an electroactive Co-containing metal-organic framework (Co-MOF) using cheap and commercially available starting materials under refluxing conditions and explored its energy storage properties in three- and two-electrode methods. The Co-MOF exhibited a specific capacitance of 425 F g-1 at 2 A g-1, maintaining a capacitance of ∼78% over 2200 successive charge-discharge cycles in a three-electrode system. The two-electrode asymmetric supercapacitor (ASC) using Co-MOF as the working electrode and as-synthesized p-phenylenediamine (PPD)-functionalized reduced graphene oxide (PPD-rGO) as the counter electrode divulged a specific capacitance of 72.5 F g-1 at 2 A g-1 current density with ∼70% capacitive retention after 2200 successive charge-discharge cycles over a broad potential window of 0-1.6 V. Moreover, the ASC demonstrated a maximum power density of 11.9 kW kg-1 at 10 A g-1 and a maximum energy density of 25.8 W h kg-1 at 2 A g-1 current density. Owing to the stable electrochemical redox (Co2+/Co3+)-mediated pseudocapacitive behavior of the Co-MOF and the high surface area and electrical conductivity of in situ generated PPD-intercalated rGO, the fabricated ASC unveiled high-performance supercapacitive behaviors. To investigate the practical applicability of this material, solid-state (ASC) devices were fabricated by employing the Co-MOF as the positive electrode and PPD-rGO as the negative electrode in a KOH-based gel electrolyte, which could power a commercially available light-emitting diode bulb (∼1.8 V) for several seconds. Therefore, the elucidated high electrochemical energy storage performance of the prepared Co-MOF makes it a very promising electrode material for supercapacitors.

Data Transfer Using Li-fi

Light-based wireless communication, abbreviated as Li-Fi or Li-Fi, uses light rather than radio waves to send data from one device to another. This technology relies on visible light communication (VLC) to transmit information through light-emitting diodes (LEDs). By modulating the intensity of the light, Li-Fi enables high-speed data transfer and can be used in various applications such as indoor positioning systems and internet connectivity in areas with high radio frequency interference. This concept was first presented by Harald Haas at a TED Global event in Edinburgh in 2011. Li-Fi, short for light-fidelity, is a light communication system that can send and receive data rapidly across the visible, ultraviolet, and infrared light spectrums. Only light-emitting diode (LED) bulbs are currently capable of transmitting data in the visible spectrum. Similar to Wi-Fi from the perspective of the end user, the technology differs primarily in that Wi-Fi transmits data by inducing a voltage in an antenna through radio waves, whereas Li-Fi does so through the modulation of light intensity. Li-Fi can operate in environments where other wireless technologies would be disrupted by electromagnetic noise (e.g.aircraft cabins, hospitals, or the military).

Intensity of Supplemental Greenhouse Lighting Affects Strawberry Plant Growth, Anthracnose Infection Response, and Colletotrichum Pathogen Development in Culture

The effect of supplemental lighting on strawberry growth and anthracnose disease response of three strawberry (Fragaria ×ananassa) cultivars was evaluated in two greenhouse trials, and the effect on strawberry anthracnose pathogens (Colletotrichum sp.) was evaluated in the laboratory. The objective of the greenhouse trials was to determine the effect of various intensities of the red and blue light emitting diode (LED) light treatment on strawberry plant vigor, injury, and disease development. In these trials, the duration of supplemental light treatments was split into two 4-hour periods: dawn and dusk. The intensity of the red and blue LED bulbs was set using an adjustable dial at 1 or 3 in trial 1 and at 1, 5, or 10 in trial 2. Illuminance and photosynthetic photon flux densities of the light treatments ranged from lows of 402 lx and 5 μmol⋅m–2⋅s–1 (blue LED 1) to highs of 575 lx and 25 μmol⋅m–2⋅s–1 (red LED 1 + blue LED 3) in trial 1, and from lows of 4213 lx and 81 μmol⋅m–2⋅s–1 (red LED 1) to highs of 7051 lx (red LED 5) and 194 μmol⋅m–2⋅s–1 (red LED 10) in trial 2. Lower light intensities in trial 1 resulted in no significant differences as a result of light treatments in relative chlorophyll content, plant vigor ratings, or disease severity ratings (DSRs). However, plant injury ratings were significantly greater in plants in the wide-spectrum fluorescent (WSF) plus ultraviolet B (UVB) light treatment compared with the other treatments. Under the higher light intensities in trial 2, there were more significant effects among light treatments. Relative chlorophyll content of plants in the WSF + UVB, WSF, and red LED 1 treatments was significantly greater than that of plants in the red LED 10 treatment; however, plants in the red LED 10 treatment had the greatest injury ratings. Detached leaves from plants in the red 5 LED and red 10 LED treatments inoculated with Colletotrichum gloeosporioides received the greatest DSRs, and leaves from plants in the red LED 1 and WSF treatments received the lowest DSRs. In the laboratory, five days of exposure to supplemental lights did not prevent the growth of isolates of three species of Colletotrichum pathogens even though the intensity of the LED lights was set at their highest intensity. However, growth of isolates exposed to the WSF + UVB light treatment was slowed.