Light Management Strategies Research Articles

Balancing artificial light at night with turtle conservation? Coastal community engagement with light-glow reduction

SUMMARYArtificial lighting is a significant threat to biodiversity. Although efforts to reduce lighting are crucial for species’ conservation efforts, management is challenging because light at night is integral to modern society and light use is increasing with population and economic growth. The development and evaluation of appropriate light management strategies will require positive public support, and a comprehensive understanding of public engagement with light pollution. This is the first study to examine public engagement with reducing light at night for the protection of a threatened species. A community campaign to reduce artificial light use was initiated in 2008 to protect marine turtles at a globally significant nesting beach. Semi-structured questionnaires assessed community engagement with light-glow reduction, using an existing theoretical constraints framework. Despite high levels of cognitive and affective engagement (knowledge and concern), behavioural engagement (action) with light reduction in this community was limited. Community perceptions of light reduction were dominated by ‘uncertainty and scepticism’ and ‘externalizing responsibility/blame’, implying that behavioural engagement in this community may be increased by addressing these widely-held perceptions using modified campaign materials and/or strategic legislation. Further refinement of the theoretical constraints framework would better guide future empirical and conceptual research to improve understanding of public engagement with critical environmental issues.

Recent advances in transition metal complexes and light-management engineering in organic optoelectronic devices.

Two of the recent major research topics in optoelectronic devices are discussed: the development of new organic materials (both molecular and polymeric) for the active layer of organic optoelectronic devices (particularly organic light-emitting diodes (OLEDs)), and light management, including light extraction for OLEDs and light trapping for organic solar cells (OSCs). In the first section, recent developments of phosphorescent transition metal complexes for OLEDs in the past 3-4 years are reviewed. The discussion is focused on the development of metal complexes based on iridium, platinum, and a few other transition metals. In the second part, different light-management strategies in the design of OLEDs with improved light extraction, and of OSCs with improved light trapping is discussed.

Light Environmental Management for Artificial Protected Horticulture

Light is a vital environmental factor that affects plant growth and development by acting on plants not only as the sole energy source of photosynthesis, but also as the kind of external signal. Light requirements of plants are subjected to species, cultivar, growth and developmental stages of plant, environmental conditions and manipulation target of yield & quality. Therefore, detailed studies on light formula (LF) based on physiological requirement are urgently needed for getting high yield and good quality in plants. With the development of semiconductor solid light sources, light-emitting diodes (LEDs), light quality physiology and light formula in plants have been gradually and extensively conducted worldwide by taking advantage of LED providing precise light spectrum and close illumination. LF defined as optimized and integrated assembly of spectral component emitting from light sources (particularly LEDs) that is suitable for plant productivity and nutritional quality formation. Based on published literatures, red, blue, and compound white light are macro-necessary light spectrum, and purple, green, yellow and orange light are micro-beneficial light spectrum, while far-red light and ultraviolet light are beneficial light spectrum. However, other light spectrum except photosynthetic active radiation, far-red and ultraviolet light is invalid for plant cultivation. Our hypothesis is that one or two kinds of necessary light quality, special micro-beneficial and beneficial light quality can make up a light formula for a kind of plant during certain period and certain environmental conditions. LF is a crucial scientific issue that should be established for protected cultivation plants with artificial light or plants that needed supplemental light. More importantly, LF is an important part of light environment management strategy (LEMS), referring to management of light intensity, LF and photoperiod. LEMS should be established for plant cultivation with artificial light sources. In this project, the application of LF and LEMS will be used in the plant factory for the advantages of entire artificial light source, cultivation with nutrient solution and intelligentized environmental control. Furthermore, vegetables, particularly leafy vegetables, will be preferentially used for the project. To sum up, the study will focus on LF which will provide technique parameters for potential efficiency (high yield and good quality) during plant growth and development.

Visual and energy management of electrochromic windows in Mediterranean climate

Industries have developed different types of transparent materials and light control systems to improve the design and the operation of buildings to take full advantage of daylight. This paper analyses energy, thermal and visual aspects connected to the integration of electrochromic windows as a part of a light control system. Energy saving and environmental control optimizations for non-residential buildings are analyzed by the advanced simulation package Integrated ENergy Use Simulation (IENUS), that can integrate thermal and visual aspects. Different double-glazed electrochromic windows and light management strategies are taken up for Mediterranean climate using Typical Meteorological Years (TMY).