Architectural Lighting Research Articles

Effects of Near Infrared Radiation in Ambient Lighting on Cognitive Performance, Emotion, and Heart Rate Variability

Although sunlight contains approximately equal amounts of near-infrared radiation (NIR) and visible light, NIR is absent from most present-day electric lighting systems and is filtered by energy-efficient windows. However, NIR is biologically active and is commonly applied in targeted photobiomodulation treatments for a range of cognitive, emotional, and physical conditions. Given the removal of NIR from indoor illumination, it is critical to understand how ambient NIR may influence psychological and physical health, and whether reduced exposure to NIR in indoor environments could be cause for concern. In a preregistered within-subjects double-blind experiment, acute effects of NIR and far-red wavelengths in ambient illumination on cognition, emotional state and cardiovascular health were examined in a sample of 151 university students (117 females, 34 males). During a 2-hour laboratory session, participants were monitored at rest and while engaged in cognitively demanding tasks across two counterbalanced lighting conditions. Both included 3500 K white light generated by a light-emitting diode (LED) system, while one additionally included LEDs with peak wavelengths in the NIR (875 nm, 960 nm) and far-red (735 nm) spectrum. The addition of NIR and far-red to the ambient lighting showed beneficial effects on resting high-frequency heart rate variability (HF-HRV), HF-HRV responses to cognitive demand, and feelings of pleasure, but reduced performance on a visual search task. These findings reveal that the absence of NIR from architectural lighting influences humans at a psychological and physiological level, with implications for health and well-being that need to be balanced with energy-saving considerations.

Tracing The Representations Of Light In The Contemporary Ch urch Architecture

Tracing The Representations Of Light In The Contemporary Ch urch Architecture

Development of preferred sizes for building-integrated lighting units (BILUs)

Building-Integrated Lighting Unit (BILU) is a new type of LED lighting product that is organically integrated with building elements and components. To promote the digital design, standardized production, and assembly construction of new lighting forms, it is necessary to establish Preferred Sizes (PSs) of BILU that are coordinated with building modules. With the aim of reduction in quantity and strength in universality, PSs were selected from BILU modular arrays in this paper. Based on the preliminary survey, a set of target sizes involving building, furniture, and home decoration elements was established to cover all application scenarios of PSs. Through a traversal search of feasible splicing methods of all PSs, the distribution of alternative PSs was analyzed with their universality quantified. Then, multidimensional metrics of alternative PSs were established, including the average feasible scheme proportion and feasible PS proportion of Line-BILU, as well as the feasible coverage-rate proportion and average coverage rate of Surface-BILU. A weighted Euclidean distance method was applied in the multi-criterion decision-making, realizing a quantitative optimization of PSs in multiple scenarios and under multiple objectives. A total of nineteen Line-BILU preferred sizes and sixty-five Surface-BILU preferred sizes were finally obtained, with their feasibility and advantages validated based on existing modular coordination standards and actual lighting project examples. These results can provide data support for establishing product specifications and design standards of BILUs, promote building industrialization from the lighting perspective, and stimulate the sustainable construction of architectural lighting.

Semantics of light as a tool for shaping the architecture of the modern era

The semantics of light is considered through the prism of a cultural phenomenon, as an object of research, as well as a tool for the formation of visual and spatial characteristics of architecture from ancient times to the architecture of the modern era. It is emphasized that light, as a tool, is semantically perceived in mythological representations, aesthetic and philosophical treatises, in the theory of architecture. An analysis of the use of light in the formation of an artistic image in the architecture of the latest era is provided from the point of view of physical-spatial, aesthetic-emotional and figurative-semantic aspects according to the levels of scale: macro-scale, meso-scale, micro-scale. The perception of architecture is revealed through the semantics of using natural light as speech, which conveys meaning through light-spatial plasticity and generates certain emotions and feelings. Spaces, objects, exhibits, parts of structures illuminated in one way or another reveal the semantic meaning of light as a powerful tool and show the external (physical) and internal (sensory) beauty and aesthetics of the object. The semantics of light in architecture affects the formation of design and general atmosphere, contributes to the creation of emotional depth and cultural significance of buildings and structures. The following semantic principles of light are highlighted in the work: the interaction of light with the urban context – the lighting design of buildings and structures is integrated into the existing urban environment to convey one or another message; conveying the symbolic meaning of light through metaphor and narrative – light is used to reinforce a key idea or theme of buildings and structures, and its meaning influences cultural identity by reflecting local features and national symbols; emotional impact and creation of an atmosphere - a variety of lighting techniques contributes to the enrichment of emotional and personal experience.

Using virtual and augmented reality to study architectural lighting

This paper presents industry stakeholder insights from the implementation of a dual modality intervention using virtual and augmented reality simulation to study complex lighting theory in architecture design. Using a design based research method the aim is to evaluate these insights and inform a pilot study to educate first year architectural design students on the complexities of lighting the built environment and methods to improve architectural workflow. The aim is to enable learners to experience natural and artificial lighting methods comparatively in real-time through multiple comparative visualisation methods. This is important to make informed evaluations regarding architectural designs in terms of spatial quality, character, performance, and user-comfort levels. This in turn allows architects to rapidly modify their designs to accommodate or mitigate the environmental effects. Outcomes from the initial usability test highlight the ability to switch back and forth between the virtual and augmented reality simulation technology, and between lighting visualisation modes as a huge step forward by the industry stakeholders. Additionally, the idea of representing the physical building where the simulation took place virtually using a detailed mapping gave a real-world anchor that made the simulations easy to navigate, leading to improved satisfaction and engagement. However, the study also highlighted improvements in the delivery of the simulation is required to improve simulation learnability and efficiency.

Visualisation in architecture – opportunities and threats

Development of computer technology, computing power of graphics cards and processors allows, with the use of appropriate software, to create extremely realistic three-dimensional images. The effects of generated visualisations can be difficult to distinguish from real photos of objects. Architects often verify the fulfilment of design goals based on a rendered digital image. Unfortunately, designers are often not fully aware of the limitations and simplifications of the tools used to create visualisations. An uncritical approach to the presented results may lead to design errors. This article presents the possibilities of visualisation in selected computer programs used by architects and cases in which correct visualisation is possible only with the use of specialised software. The article pays special attention to the possibility of errors in the visualisation of architectural lighting.

Performance comparison of different filters based on fibre optic lighting systems and evaluation of architectural lighting effects

Plastic optical fiber lighting is a feasible green lighting method for buildings. This study first derives a mathematical model for the focused light energy absorbed by optical fibers. Based on the variable relationships in the mathematical model, the cooling mechanism of plastic optical fibers was obtained. Secondly, a dual-axis automatic sun-tracking concentrating lighting equipment capable of carrying nine Fresnel lenses was designed. The equipment was used to compare the filtering and cooling effects of two types of filter devices: infrared filters and heat-insulating film. The cooling and lighting effects of these two types of filter devices were also evaluated. Subsequently, the impact of fiber loops on lighting was discussed. Finally, the b2 and b3 modules of the dual-axis automatic sun-tracking concentrating lighting equipment were applied in dark stairwells. The results indicate that the temperature of optical fibers can be reduced by using filtering devices and enhancing heat radiation and convection on the surface of optical fibers. Infrared filters exhibit better cooling and lighting effects than heat-insulating film. Looping the fiber cable reduces the effect of fiber lighting, and the higher the number of loops, the higher the loss of fiber lighting. The dual-axis automatic sun-tracking concentrating lighting equipment increased the illuminance value in the stairwells to over 50 lux, showing great application potential in architectural lighting.

Lighting design method of a football stadium considering visualization

This research is about implementation of visualization to evaluate and correct lighting state and characteristics of lighting engineering on computers in lighting design of football pitch considering shelter and tower. The visualization of architectural lighting and ornament with lamplights designs has not been studied in detail until now in the world, and the method of visualization design for achieving FIFA standards in asymmetric four-tower football stadium lighting is described in the light mode and under the brief introduction by the lighting simulation programs DIALux and Relux..

Preface

The 9th Light Symposium, December 4-6, 2023 · Stockholm, Sweden Light Symposium 2023: Architecture Lighting Environments - Space With(Out) Light Daylight and electric light are an integral part of our built environment, and the sustainable design of lighting in this context, its presence, absence, and variability over time, requires research and practice that is both trans- and interdisciplinary.Although the presence of light is intimately linked to the life of humans, flora, and fauna, research and practice have not yet fully explored how light and dark can shape the built environment in a sustainable and holistic way.Research and practice into the affects and effects of light combine lighting design with other fields, including, for example, architecture, engineering, computer science, visualization, arts, humanities, social sciences, environmental psychology, health sciences, cognitive sciences, and more. The Light Symposium is an annual, international event to facilitate discussions and the exchanging of ideas; currently, it is coordinated by four academic partners; the Lighting Design Division at KTH in Sweden, Hochschule Wismar in Germany, AAU Copenhagen in Denmark, and SNU Kongsberg in Norway.The 9th Light Symposium, LS2023, was held in Stockholm from the 4th-6th of December 2023; it was hosted by the Architectural Lighting Design Division of KTH Royal Institute of Technology, in collaboration with the Perception Studio of Konstfack, the University of Arts, Crafts, and Design. During the 2,5 days of the symposium, more than 200 participants came together to share and learn about current research and design across different fields within architectural and urban lighting.In addition to invited keynote lectures, the conference program consisted of sessions with talks, panel discussions and poster presentations from researchers and practitioners worldwide, selected through a two-step peer-review process. The conference topics included daylight and electric light in architecture, art, and urban design, organized into four broad categories: Light and Health for all Species, Designing for Darkness, Sensory and Spatial Perceptions, Variability and Rhythmicity.These proceedings include 32 conference papers that were presented either as talks or posters during LS2023. All papers were reviewed by an international panel of reviewers. We thank all reviewers and our partner organizations for their time and help.We also thank the following organizations for their support of LS2023, and for enabling documentation through recordings and proceedings: The Swedish Energy Agency, Bertil & Britt Svenssons Stiftelse för Belysningsteknik, as well as Helvar, Selux, Fergin, Nordic LED, Stockholm Lighting, Annell, Fox Belysning, Optoga.The LS2023 Local Organizing Committee and Proceedings Editorial Team: Ute Besenecker, Foteini Kyriakidou, Gerhard Rehm, Hamidreza Eizadi, Federico Favero, Rodrigo Muro, Johanna Enger, Stavroula Angelaki, Seren DincelList of Reviewers are available in this Pdf.

Light and Emotional Architecture: An Embodied Experience

The presented explorative research focuses on the phenomenological relationship and emotional impact of light within architectural spaces, grounded in a pilot study and literature review. Serving as the foundational framework for a Ph.D., this study aspires to decipher the role of light in Emotional Architecture—a term introduced by the German artist Mathias Goeritz in his 1953 architectural manifesto crafted in Mexico. This multidimensional pilot study employs experiential observation and structured interviews, complemented with qualitative and quantitative documentation, all anchored by literature-based insights. Set in the Barragán House, which served as both the studio and residence for the renowned Mexican architect Luis Barragán since 1948, the study endeavours to elucidate how architectural nuances—like form, materials, colours, and arrangements—affect lighting conditions, subsequently shaping human emotions and experiences. Through twenty-two interviews, the research captured perceived atmospheres and the inherent intentionality of affordances in architecture, revealing a strong correlation between spatial impact on observers and light-related experiences. The interplay between these elements suggests a compelling avenue for implementing Emotional Architecture conducive to both individual and societal sustainable development.

Regulation of chromatin architecture by transcription factor binding.

Transcription factors (TF) bind to chromatin and regulate the expression of genes. The pair Myc:Max binds to E-box regulatory DNA elements throughout the genome to control the transcription of a large group of specific genes. We introduce an implicit modeling protocol for Myc:Max binding to mesoscale chromatin fibers at nucleosome resolution to determine TF effect on chromatin architecture and shed light into its mechanism of gene regulation. We first bind Myc:Max to different chromatin locations and show how it can direct fiber folding and formation of microdomains, and how this depends on the linker DNA length. Second, by simulating increasing concentrations of Myc:Max binding to fibers that differ in the DNA linker length, linker histone density, and acetylation levels, we assess the interplay between Myc:Max and other chromatin internal parameters. Third, we study the mechanism of gene silencing by Myc:Max binding to the Eed gene loci. Overall, our results show how chromatin architecture can be regulated by TF binding. The position of TF binding dictates the formation of microdomains that appear visible only at the ensemble level. At the same time, the level of linker histone and tail acetylation, or different linker DNA lengths, regulates the concentration-dependent effect of TF binding. Furthermore, we show how TF binding can repress gene expression by increasing fiber folding motifs that help compact and occlude the promoter region. Importantly, this effect can be reversed by increasing linker histone density. Overall, these results shed light on the epigenetic control of the genome dictated by TF binding.

Regulation of chromatin architecture by transcription factor binding

Transcription factors (TF) bind to chromatin and regulate the expression of genes. The pair Myc:Max binds to E-box regulatory DNA elements throughout the genome to control the transcription of a large group of specific genes. We introduce an implicit modeling protocol for Myc:Max binding to mesoscale chromatin fibers at nucleosome resolution to determine TF effect on chromatin architecture and shed light into its mechanism of gene regulation. We first bind Myc:Max to different chromatin locations and show how it can direct fiber folding and formation of microdomains, and how this depends on the linker DNA length. Second, by simulating increasing concentrations of Myc:Max binding to fibers that differ in the DNA linker length, linker histone density, and acetylation levels, we assess the interplay between Myc:Max and other chromatin internal parameters. Third, we study the mechanism of gene silencing by Myc:Max binding to the Eed gene loci. Overall, our results show how chromatin architecture can be regulated by TF binding. The position of TF binding dictates the formation of microdomains that appear visible only at the ensemble level. At the same time, the level of linker histone and tail acetylation, or different linker DNA lengths, regulates the concentration-dependent effect of TF binding. Furthermore, we show how TF binding can repress gene expression by increasing fiber folding motifs that help compact and occlude the promoter region. Importantly, this effect can be reversed by increasing linker histone density. Overall, these results shed light on the epigenetic control of the genome dictated by TF binding.

Light as a Tool of Emphasis in the Interior of Residential Buildings

This paper examines the interaction between architecture and lighting, highlighting their cooperative connection in creating captivating experiences within interior spaces. The study is based on a qualitative research approach and explores three interconnected themes, which are ‘Light as a Tool of Emphasis, the Dynamic Emphasis of Daylight, and the Appeal of the Flexibility of Lighting in Emphasis’. When examining the various aspects of lighting in architecture, the initial theme is its significant influence on the way users perceive and behave. Examining both qualitative and quantitative elements, this theme explores the factors of visibility, colour rendering, and emotional reactions elicited by various lighting designs. This theme also emphasizes the use of modern lighting design in homes, with fixtures that fulfil both practical and visual purposes. In addition to its traditional relationship with energy efficiency, the second theme looks into the dynamic role of daylight in architectural spaces. With this theme, architects can evaluate the qualitative characteristics of daylight by utilizing a matrix consisting of 10 shades, which provides them with a conceptual framework. This theme also highlights the interaction between natural and artificial lighting, demonstrating how they collectively impact visibility, aesthetics, and energy efficiency. The third theme emphasizes the importance of the flexibility of lighting design, enabling it to adapt to various spatial roles. Lighting that is focused on human needs can be adjusted in intensity and colour temperature to promote flexibility in the use of space, enhance the well-being of inhabitants, and utilise for a range of aesthetic possibilities. Integration of smart lighting augments adaptability and intelligence in architectural lighting. Synthesizing these concepts, the discussion section of this paper highlights lighting's dynamic narrative role, transcending utilitarian approaches. It presents architects and designers as storytellers constructing experiences through sophisticated light utilization, resonating with the human condition. Acknowledging its qualitative nature, the study recommends further research avenues. It suggests quantitative investigations into the psychological and physiological implications of distinct lighting schemes and advocates refining typologies for diverse architectural situations. In conclusion, this paper improves lighting design's status as a dynamic, integrated architectural story component. Architects are taught to embrace their position as architects of engaging stories through the skilful instrumentation of light.

A Connection Through Stucco Technique with Early Medieval Natural Lighting Systems in Rome and Emphasis on the Role of Light in Islamic Architecture Focusing on Khirbat al-Mafiar 7CE.

This article investigates how, since ancient times, building windows have had grids of stucco, stone, wood, or iron, as well as slabs of glass or other materials. They also appeared as simple apertures in the wall, the arrangement of which frequently served decorative functions. Following a classical tradition, the usage of shuttered windows with glass fixed on timber frames was known in late antiquity. The search for a peculiar architectural taste of the late antique and early mediaeval times is particularly appealing due to the light effects produced by shuttered windows made of translucent material, which provides a mystical and suggestive appearance.
 The light that transforms the decoration, using color combinations, sometimes occur in unexpected contexts or in an adjacent architectural form, such as the floor and vault of the royal apse in the bathroom of Khirbat al-Mafjar. The architectural element that includes the lozenges, closer to Khirbat al-Mafjar as a drawing and scheme, to create a particular visual effect, could be seen in three barriers of stucco windows found in situ in the windows of the central nave during the 1930 restorations to Bovino Cathedral. Presence of light during history and in various architectural oeuvres, in addition to functional aspect, as factor for illumination and life conferring to daily activities, it has been abundantly addressed from spiritual aspect and in doctrinal discussions of religions.

The Angular Use of Light in Architecture and the Concept of Space

In this study, the analysis of the understanding of space under the influence of light was made. The content of the study touched on the effect of light and space on human perception, both architecturally and computationally. The identity that the light adds to the space, the interaction of the material with the light, and the illusory properties of the light are explained. While examining these abstract concepts, the illumination area of the light was calculated with a computational application. The fact that light is one of the most effective elements used in space has revealed the necessity of designing form, material, and lighting together. It is understood that the effect of basic elements that make up space, such as form and material color, can be increased with angular lighting. It has been understood that if a textured surface is illuminated with a directional light, the visual effect of the surface will increase. However, it has been understood that a material with a smooth structure and a material with a rough structure cannot be illuminated with the same lighting method, and this visual effect will create negativity. For original lighting designs, it is necessary to make accented or homogeneous lighting according to the need, and it is possible to provide this with designed-planned lighting.

Daylight Analysis in Terms of Building Direction and One-Way Roof

The location of the buildings in the residential area is very important in protecting or benefiting from sunlight. The dynamic structure of the sun, which constantly changes according to time and seasons, directly affects the building's architecture and urban formation. Ignoring the sun's use of the structures during the construction of the buildings can cause significant disturbances to the residents. Daylight strategies, which are also influenced by climate, depend on the availability of natural light, determined by the latitude of the building site and the instantaneous conditions around the building. High latitudes have different summer and winter conditions, with lower daylight levels in winter. At these latitudes, designers often aim to maximize daylight penetration in buildings. In the tropics, where daylight levels are high throughout the year, the design emphasis is often on preventing overheating by limiting the amount of sunlight entering the building. Daylight availability depends not only on latitude, but also on the orientation of a building, and each facade and material of the building requires a different design importance. Therefore, daylight and architectural design strategies are two inseparable phenomena. In this respect, examining traditional architecture and successful natural lighting designs in the past is very useful for understanding climate-balanced building design. For this purpose, determining the roof slope according to the sun angle in architectural structures by calculating according to the location provides efficiency in many issues from energy efficiency to human health.

Describe Fashion Products via Local Sparse Self-Attention Mechanism and Attribute-Based Re-Sampling Strategy

In this paper, we convert conventional image captioning task into a new paradigm in the fashion domain, fashion item captioning. This task requires the ability of associating a group of item angles and generating a longer and more fine-grained description. To link several images in a more efficient way, we propose a local sparse self-attention mechanism(LSAM), which only enables one region to interact with those in the adjacent area and allows a lighter architecture with fewer layers. To capture more subtle details of the item, an attribute-based re-sampling strategy(ARS) is introduced to enhance the learning on those low-frequency but content-related attribute words. Besides, existing fashion datasets are limited in the quality of annotations and single fashion style. To bridge this gap, we propose a novel dataset for fashion item captioning, termed Fashion Item Captioning Dataset(FICD). FICD provides a meaningful complement to the existing fashion datasets, which comprises 294K images, 62K real-world product descriptions with diverse linguistic styles, rich attributes and categories. It is worth mentioning that we also annotate an attribute-level sentence for each item, which enables the FICD to be used not only for fashion item captioning but also for other fashion-related tasks. Moreover, the complex structure is even more restrictive for application to real-world scenarios. Without bells and whistles, our framework is simply designed with an end-to-end manner. Extensive experiments demonstrate the effectiveness of our LSAM-ARS. More remarkably, LSAM-ARS achieves state-of-the-art performance on FACAD and FICD datasets, with the CIDEr-D score being increased from 65.4% to 81.8%, 69.8% to 77.4%, respectively.

Architectural Design Qualities of an Adolescent Psychiatric Hospital to Benefit Patients and Staff.

This study is focused on how architectural design of adolescent psychiatric hospitals could positively affect not only patients but also staff members working at the hospitals. Adolescents between the ages of 12 and 18 are among the young population with the highest percentage of mental illness. However, there are limited number of intentionally designed psychiatric hospitals for adolescents. Staff who work in adolescent psychiatric hospitals may face workplace violence. Studies on environmental impacts suggest that the built environment affects patients' well-being and safety as well as staff's satisfaction, working condition, safety, and health. However, there are very few studies that focus on adolescent psychiatric hospitals and the impact of the built environment on both staff and patients. Data were collected through literature analysis and semi-structured interviews with staff of three psychiatric state hospitals with adolescent patient units. The triangulation of multiple data sources informed a set of environmental design conditions that captures the complexity and connectedness of architectural design and the occupants of an adolescent psychiatric hospital. The results present architectural composition, atmosphere, lighting, natural environment, safety, and security as indispensable design conditions to create an enclosed and city-like campus that provides a serene, secure, and structured environment that benefit staff and adolescent patients. The specific design strategies that need to be incorporated in the architectural design of a safe and secure adolescent psychiatric hospital include an open floor plan that respects patients' autonomy and offers privacy while always providing staff with full visibility of patients.

Choosing a Method for Approximating the Spectral Distribution of Colour LEDs and Comparing their Parameters and Characteristics in Nominal Mode

New technologies and new light sources make it possible to create fundamentally new approaches in the design and construction of lighting devices. Light emitting diodes (LEDs) are a relatively new, promising and energy-efficient light source with a few unique properties: long lifetime, high luminous efficiency, aesthetics, environmental friendliness, reliability, high durability, and possibility to create a variety of spectra easily. During the lighting devices development, it is convenient to use mathematical approximations of the spectral distributions of the used LEDs in the composition of the product to calculate the final spectrum of the device in the visible range. These calculation methods are particularly interesting in architectural lighting. They are also applicable to the development of modern LED greenhouse irradiators. The article considers two main methods for approximating the emission spectra of colour LEDs: via symmetric and asymmetric distribution. The spectral distributions of four main types of LEDs that are used in the lighting devices design based on colour LEDs were measured in a wide range of currents from 100 mA to 1000 mA: red, amber, green, and blue. The results were also compared with a model that considers the two-dimensional density of states and potential fluctuations in the active region of the heterostructure of LED. Based on the carried-out measurements and calculations, the optimal approximation method via the asymmetric spectral distribution of LED radiation was determined.

A New Principle for Building Simulation of Radiative Heat Transfer in the Presence of Spherical Surfaces

Radiant heat interchanges are pivotal to assessing the energy use of buildings and facilities that channel some sort of solar radiation. Form factor integrals are needed for an accurate simulation of the main features of the envelope of such buildings. However, the expressions required when the space under analysis is curved, for instance, in domes and vaults, are not feasible. The calculation process of algorithms is usually addressed by cumbersome analytical deductions or else by rough statistical approximations included in the simulations, such as ray-tracing methods. Neither of which works properly under curved geometries. The following article deals with an innovative methodology for employing an exact property that solves any spherical configuration of the radiant surfaces. The newly found relationship is validated by comparison with other solutions previously deducted by the author and by numerical simulations when available. Since there is no other exact method of calculating radiation exchanges within spherical fragments, we consider that this finding represents an advance which contributes to overcoming a variety of unexplained and practical problems of radiative heat transfer applicable to architectural developments, lighting elements and aircraft components.