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The concept of lighting is of great importance in providing the security that people need so that they can have a quality of life and in meeting their aesthetic needs. Lighting design is related to the physical structure and the environment, and thanks to the lighting design, the aesthetic and functional needs of people will be met and the quality of life will be increased. The need to reflect the historical, cultural and aesthetic values of the city has brought the issue of urban lighting to the agenda. Lighting systems, which are applied without paying attention to the necessary lighting standards and criteria, cause some problems in urban spaces. One of these problems is light pollution; It is generally defined as the use of light in the wrong place, in the wrong amount, in the wrong direction and at the wrong time. Light pollution adversely affects the natural life and daily lives of people, and it is necessary to take various measures to eliminate such negativities in human life, to detect and eliminate these problems. In this study; The standards for the lighting of the city parks obtained by the literature studies were determined, the current lighting situation of the Butterfly Valley Park and the recommended lighting design produced by the Relux software in accordance with the standards. According to the findings; In the current lighting project, the total power consumed as a result of the lighting of all the lamps of the area has been calculated as 96 005.0 W. In the proposed lighting project, the total power consumed as a result of the burning of all lamps was calculated as 27 630.0 W. The obtained energy gain was found to be 96 005.0 W – 36 700.0 W = 68 375.0 W. As a result of working in the light of this information, energy savings of 1 in 3 have been achieved.

The smart street-lighting system (SSLS) is a leading candidate in the smart city. By the time of the last 15 cycles, many meaningful improvements have been executed in the SSLS with the impact of the internet of things technologies and universal networking devices. Conventional smart street lighting systems are restricted to wireless sensor networks, mobile devices, and old lighting control systems. This article presents a comprehensive treatment of network designs, namely communication, control, and wireless sensor-based smart street lighting system by deploying based on their existing system architecture, and network topologies including leading with it a host of privileges. In addition, choosing the right lighting class, high-intensity discharge (HID) lights, and retrofitting lighting technologies have all been covered in detail. This paper's objective is to evaluate various control technologies that may support the many applications deployed on networked streetlights. Moreover, issues and recommendations, distinguished in this paper, will pave the route for future smart street lighting systems that promote a reliable and seamless driving experience and are energy-efficient for environmental sustainability. It is far anticipated that LoRa and Sigfox with additional gateways could be the best possible smart street lighting system options as these technologies are facilitated for long distances but with a limited data rate. It is way more suitable for lighting control compared to other protocols to control thousands of streetlights.

In order to optimize light distribution for promoting biomass growth rate of Chlorella pyrenoidosa, concave walls were installed in plate photobioreactors (PBR) to generate rotational flow field of microalgal solution circulated from top inlets to bottom outlets. Flow vortices in four corners of concave-wall PBR resulted in decreased mixing time and increased mass transfer coefficient. The CO2 bio-fixation by C. pyrenoidosa increased by 27% and chlorophyll-a concentration enhanced by 18.5% in concave-wall PBR compared to those in control (flat-wall) PBR. The concave walls diverge light rays to enhance frontal light exposure and supply more light photons into interior regions of PBRs. The promotion in light distribution and vortex flow field with concave walls enhanced light and nutrients utilization by microalgal cells, leading to an increased biomass growth rate by 21%.

The laboratory study of microalgae can be experimentally challenging. In addition to the cultivation requirements of non-photosynthetic microorganisms, phototrophs also require illumination. Routinely, researchers seek to provide custom light supplies, i.e., vary the light intensity and time over which it is delivered. Such flexibility is difficult with standard benchtop lights. Usually, cultivation studies also require growth comparisons between experimental treatments. Frequently, growth is assessed over an extended duration, e.g., multiple times a day over a week-long trial. Manual measurements can be time-consuming and lack data resolution. Therefore, photobioreactors (PBRs) with automatic growth monitoring and customizable light supply are useful for replicated experiments with multiple treatments. The current work presents the design, construction, and operation of laboratory PBRs. The materials are easily sourced and relatively inexpensive. The design could be duplicated with moderate skill. Each structure has a footprint of ~40 cm2 and hosts three 1 L glass bottles for triplicate replication. Bottles rest upon platforms containing magnetic stirrers and are arranged vertically within a 1 m high and 15 cm diameter polyvinyl chloride (PVC) pipe. The pipe interior is lined with light-emitting diodes (LEDs). These LEDs produce continuous light intensities from 0-2400 µmol photons m-2 s-1 of photosynthetically active radiation (PAR). Users design a custom lighting program. The light intensity can be adjusted each second or held constant for longer durations. Oxygen produced from photosynthesis exits each bottle via a one-way volumetric gas sensor. Software is used to record gas sensor data. The amount of oxygen produced can be correlated to biomass growth. If biomass samples are required, a syringe can be used to extract culture. The method is suited for microalgae grown with bicarbonate as the carbon source. These PBRs are valuable to a laboratory that requires replicated experiments, light regime flexibility, and continuous high-resolution growth data.

The Internet of Things (IoT) is opening up new services and is stimulating changes in industries. The lighting industry is also embracing this change by establishing an Internet of Lights (IoL). This article highlights the main benefits and the challenges to face while going towards IoL. To address these challenges and cater to the specific requirements of lighting networks, an IoL reference architecture, Open Architecture for Intelligent Solid State Lighting Systems (OpenAIS), has been proposed. This article provides an overview of the OpenAIS architecture and explains how one can design specific systems based on this architecture. It also zooms into the configurations and design choices made in a pilot system in a real office building showing the validity of the architecture. A comparison of the OpenAIS system with a state-of-the-art commercial solution shows that IoL systems can exceed proprietary systems in several key performance indicators, such as security, interoperability, extensibility and openness.

【Objective】Light is the most important factor affecting plant growth, development, metabolism and external phenotype. In the process of plant growth, artificial light sources are often used instead of natural light to fill the seeds and seedlings to improve the quality, yield and efficiency of fruits and vegetables. Artificial light plant is one of the important ways for standardized and efficient seedling cultivation, but its high energy consumption, accounting for 60% to 80% of the total energy consumption of plant factories, seriously hinder the promotion and application of factory seedling technology. Therefore, reducing the energy consumption of light source and improving the utilization rate of light is one of the core goals for plant seedling.【Method】Aiming at the problems of fixed height, high energy consumption and difficult to match the light demand of seed and seedling growth, this study developed a precise light cultivation platform for seedlings based on Programmable Logic Controller (PLC) technology by combining theoretical analysis, model construction and experiment. Taking cucumber seedlings as the object, the performance of the light intensity control system of the precision light cultivation platform for seedlings was verified, and its effect on the growth of cucumber seedlings was explored.【Result】The experimental results showed that the light intensity and light distribution uniformity were improved after the optimization of the lamp bead structure. The developed platform can fill the light of cucumber seedlings by manual, automatic, Human Machine Interface (HMI) and host computer. Through the platform optical radiation energy consumption model and the layer level adjustment control strategy, the LED operating power is effectively reduced, saving about 40.65% of electric energy. The maximum and minimum relative error of the optical platform radiation model are 34.37% and 3.57%, respectively, and the average relative error is 11.45%. Cultivation experiments showed that under the same light intensity treatment, there was no significant difference in seedling phenotype parameters and strong seedling index by comparing the precision light cultivation platform with the traditional high floor fixed platform.【Conclusion】The precision light cultivation platform of seedlings based on PLC technology realizes automatic lifting and intelligent dimming, and saves up to 40.65% power without affecting the growth of seedlings.

The main function of the photosynthetic process is to capture solar energy and to store it in the form of chemical 'fuels'. Increasingly, the photosynthetic machinery is being used for the production of biofuels such as bio-ethanol, biodiesel and bio-H-2. Fuel production efficiency is directly dependent on the solar photon capture and conversion efficiency of the system. Green algae (e.g. Chlamydomonas reinhardtii) have evolved genetic strategies to assemble large light-harvesting antenna complexes (LHC) to maximize light capture under low-light conditions, with the downside that under high solar irradiance, most of the absorbed photons are wasted as fluorescence and heat to protect against photodamage. This limits the production process efficiency of mass culture. We applied RNAi technology to down-regulate the entire LHC gene family simultaneously to reduce energy losses by fluorescence and heat. The mutant Stm3LR3 had significantly reduced levels of LHCI and LHCII mRNAs and proteins while chlorophyll and pigment synthesis was functional. The grana were markedly less tightly stacked, consistent with the role of LHCII. Stm3LR3 also exhibited reduced levels of fluorescence, a higher photosynthetic quantum yield and a reduced sensitivity to photoinhibition, resulting in an increased efficiency of cell cultivation under elevated light conditions. Collectively, these properties offer three advantages in terms of algal bioreactor efficiency under natural high-light levels: (i) reduced fluorescence and LHC-dependent heat losses and thus increased photosynthetic efficiencies under high-light conditions; (ii) improved light penetration properties; and (iii) potentially reduced risk of oxidative photodamage of PSII.

Proceeding of: IEEE Conference on Standards for Communications and Networking (CSCN 2022), 28-30 November 2022, Thessaloniki, Greece In the framework of Industry 4.0, visible light communications (VLC) are proposed for providing connectivity in those environments where radio-frequency (RF) transmission achieves a poor performance or it is even banned [1] . Specifically, VLC are potentially useful for providing Internet of Things (IoT) services while consuming a small portion of the transmission resources, considering a user-centric approach and subject to a low-cost implementation [2] . Recently, the European Commission warned about the need for employing low-cost and energy-efficient LEDs for future VLC systems to maintain the reduction in the energy consumption [3] . As a consequence, the VLC-IoT hardware implementations must consider commercial LEDs, which are subject to non-linearities, reduced and unknown bandwidth and other impairments for data transmission, while maintaining the energy efficiency for illumination purposes. In this work, a low-cost VLC-IoT implementation is presented based on commercial high-power LEDs. The proposed configuration is focused on providing connectivity in those environments where RF transmission is not efficient so that an external access point (AP) distributes the connectivity through a backhaul link that feeds the set of optical access points (APs). This work has received funding from the European Union Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie ETN TeamUp5G, grant agreement No. 813391, and from Spanish National Project IRENE-EARTH (PID2020-115323RB-C33) (MINECO/AEI/FEDER, UE). The work of Máximo Morales-Céspedes is also supported by the Juan de la Cierva Incorporación under Grant IJC2019-040317-I.