scholarly journals Simulating Physiological Potentials of Daylight Variables in Lighting Design

2022 ◽  
Vol 14 (2) ◽  
pp. 881
Author(s):  
Mimi Ravn ◽  
Gabriela Mach ◽  
Ellen Kathrine Hansen ◽  
Georgios Triantafyllidis
Keyword(s):  
Vertical Plane ◽  
Holistic Approach ◽  
Lighting Design ◽  
Time Of Day ◽  
Physiological Effects ◽  
Smart Building ◽  
Light Levels ◽  
Orientation Time ◽  
Specific Factors ◽  
Sky Conditions

A holistic approach to daylight dynamics in our built environment can have beneficial outcomes for both physiological and visual effects on humans. Simulations of how daylight variables affect light levels on the horizontal work plane are compared to their physiological effects, measured as melanopic EDI (Melanopic Equivalent Daylight Illuminance) on a vertical plane. The melanopic EDI levels were calculated in a simulated office space in ALFA software (Adaptive Lighting for Alertness) employing the daylight variables of orientation, time of day, season, sky conditions and spatial orientation. Results were analyzed for how daylight design can contribute to the physiological effects of dynamic light in office buildings. Daylight is shown to be a sufficient light source in the majority of cases to meet the recommended values of EDI and provide the suggested horizontal lx level according to the Danish Standards. A mapping of daylight conditions, focusing on the specific factors presented here, can provide guidelines in the design process and future smart building systems. The complex interrelationship between these parameters is important to acknowledge when working with daylight dynamics as a sustainable element in architecture and lighting design.

A Practical Tool for Ambient Illumination Comparisons at Dusk/Dawn

2016 ◽  
Vol 60 (1) ◽  
pp. 470-474 ◽  
Author(s):  
Hilary Lam ◽  
Sayf Gani ◽  
Randy Mawson ◽  
Jason Young ◽  
Erin Potma
Keyword(s):  
Human Perception ◽  
Time Lapse ◽  
Time Of Day ◽  
Ambient Illumination ◽  
Adjustment Factor ◽  
Lighting Conditions ◽  
Accurate Knowledge ◽  
Ambient Lighting ◽  
Practical Tool ◽  
Sky Conditions

Nighttime visibility is an important consideration in collision reconstruction and personal injury investigation. Decreased contrast in low ambient lighting conditions can greatly affect human perception and response. Because ambient lighting levels change rapidly at dawn and dusk, forensic investigators must have an accurate knowledge of the time of day and the cloud conditions at the time of the incident before initiating a nighttime visibility assessment. Previously, human factors experts attempting re-enactments at dawn or dusk have had to wait for sky conditions that match those at the time of the incident, making the investigation of those cases extremely difficult, if not unfeasible. In this study, an ambient illumination equivalency tool has been developed based on a database of time-lapse light meter readings collected by the authors. This new tool can be used to facilitate nighttime visibility assessments on any day by providing a time adjustment factor to account for the changes in ambient illuminance due to differences in the cloud conditions between the day of the incident and the day of the re-enactment.

scholarly journals Energy Efficient Lighting Design Criteria: Cost-Effective Solutions in an Industrial Environment

2007 ◽  
Author(s):  
Frank J. Agraz ◽  
John Maneri
Keyword(s):  
Energy Consumption ◽  
Energy Efficient ◽  
Return On Investment ◽  
Energy Savings ◽  
Cost Effective ◽  
Lighting Design ◽  
Design Criteria ◽  
Lighting System ◽  
Light Levels

The continual rising cost of energy, existing outdated lighting technology, and inefficient lighting designs have given property owners the opportunity to improve their facilities by retrofitting their existing luminaires with an energy efficient lighting system. A lighting retrofit uses the existing electrical infrastructure to replace, relocate, or convert existing luminaires with the latest generation of cost-effective components. New lighting technology has emerged within the last 6 years that generates energy savings of 40% to 50% while maintaining existing light levels. These upgraded and field-tested solutions lower energy consumption, generate a healthy financial return on investment, and can improve both the quality and quantity of light in the task area. As with any other solution, a cost-effective lighting system must be designed and engineered carefully to accommodate the needs of each work space. Simply installing a new lamp into an existing luminaire will not necessarily guarantee substantial energy savings or an improved lighting environment. In any space that uses electric lighting, the lighting designer must evaluate potential solutions for energy consumption, maintenance concerns, delivered light levels, hostile environments, and the overall economic impact of installing and long-term operation of the new system. In this paper, the author will discuss energy efficient lighting design criteria and how a lighting designer properly engineers a retrofit project to deliver energy savings without sacrificing light levels. The discussion includes a summary of both traditional and emerging technologies, and the long-term impact on energy consumption, maintenance, return on investment, lighting quality, and delivered light levels. Paper published with permission.

Effect of Application Factors on Efficacy of Fluazifop-P-Butyl in Flax

1991 ◽  
Vol 5 (3) ◽  
pp. 504-508 ◽  
Author(s):  
George H. Friesen ◽  
David A. Wall
Keyword(s):  
Growth Stage ◽  
Field Experiments ◽  
Time Of Day ◽  
Wild Oat ◽  
Spray Nozzle ◽  
Green Foxtail ◽  
Drought Conditions ◽  
Orientation Time ◽  
Moisture Conditions ◽  
Nozzle Orientation

Field experiments were conducted to determine the efficacy of fluazifop-P-butyl for the control of green foxtail, wild oat, barley, and wheat in flax as influenced by spray nozzle orientation, time of day, and growth stage. Under drought conditions in 1988, control of wild oat, wheat, and barley with fluazifop-P-butyl was enhanced 75%, 53% and 78%, respectively, when nozzles were oriented to spray forward 45°. Under adequate soil moisture conditions enhancement of control was minimal. Green foxtail control improved when fluazifop-P-butyl was applied from 1700 to 2100 h, but time of day had no effect on control of wild oat, barley, or wheat. Fluazifop-P-butyl effectiveness was reduced when applied 4 d after flax emergence due to late emerging grass seedlings. Green foxtail was the most tolerant to fluazifop-P-butyl, whereas wild oat, wheat, and barley were the most susceptible.

A geochemical profile of the Swan Hills Reef

1968 ◽  
Vol 5 (2) ◽  
pp. 287-309 ◽  
Author(s):  
E. M. Cameron
Keyword(s):  
Solid Solution ◽  
Vertical Plane ◽  
Emission Spectrometry ◽  
Windward Side ◽  
Direct Reading ◽  
Vertical Variation ◽  
Analysis Techniques ◽  
Geochemical Profile ◽  
Magnesian Calcite ◽  
Specific Factors

Over four hundred samples were taken from cores that form a vertical plane section through the Swan Hills Reef, an important oil-bearing reservoir in the Devonian rocks of west-central Alberta. Quantitative determinations for eight elements were made on the samples by direct-reading emission spectrometry. The resulting chemical data were treated by R-mode factor analysis techniques, including rotation to oblique solutions and the computation of factor scores. The distribution of the different factors within the reef was then determined by computing trend surfaces for the scores. Factors with low eigenvalues and even specific factors were found of considerable use for interpreting the data.Dolomite in the reef appears to be derived mainly from high-magnesian calcite of possible algal origin that was formed on the windward side of the reef. Sr held in calcite as a solid solution impurity shows a primary trend to depletion in the organic framework facies that margins the reef. This is caused by greater diagenetic leaching of these rocks. Secondary variation of Sr may indicate periods when the reef was elevated above sea level and underwent subaerial weathering. Vertical variation of Mn and Fe held in solid solution in calcite appears to be related to tectonic changes in the region.

Factors controlling the tentacle and polyp expansion behaviour of selected temperate Anthozoa

2006 ◽  
Vol 86 (5) ◽  
pp. 977-992 ◽  
Author(s):  
James J. Bell ◽  
Claire Shaw ◽  
John R. Turner
Keyword(s):  
Predator Avoidance ◽  
Current Flow ◽  
Time Of Day ◽  
High Current ◽  
Light Levels ◽  
Turbulent Flow Regime ◽  
Flow Turbulence ◽  
Predator Abundance ◽  
Expansion Behaviour ◽  
Anemonia Viridis

Although the factors influencing patterns of expansion and contraction of polyps and tentacles for tropical anthozoans has been well described there is still little information for temperate species. This study investigated the patterns of tentacle and polyp expansion behaviour of nine species of temperate Anthozoa in response to current flow, turbulence, food availability and time of day (light) at Lough Hyne Marine Nature Reserve (Ireland). In the absence of current flow, Metridium senile, Caryophyllia smithii, Alcyonium hibernicum and Corynactis viridis exhibited nocturnal expansion of polyps or tentacles with contraction occurring in the daytime, while Alcyonium digitatum, Actinia equina and Cerianthus lloydii showed no differences between light and dark periods. The symbiont containing species Anthopleura ballii and Anemonia viridis expanded or raised their tentacles during daylight hours (tentacle contraction is not possible for A. viridis), although in shallow waters (3 m) Anthopleura ballii tentacles were contracted at midday (highest light levels) presumably to prevent damage from ultraviolet radiation. The contraction of tentacles during light periods was considered a predator avoidance response since zooplankton availability did not vary between light and dark periods, while predator abundance (particularly fish) is greater during daylight. Even though M. senile, Alcyonium hibernicum and Corynactis viridis showed little expansion during daylight periods in the absence of current flow, tentacles and polyps were expanded at midday during periods of high current flow. A greater number of expanded polyps and tentacles were also recorded for A. digitatum, Anemonia viridis and Cerianthus lloydii during high flow conditions compared with periods of low/no flow (Caryophyllia smithii not examined). Actinia equina only exhibited tentacle expansion in response to the creation of a turbulent flow regime, which was determined from laboratory observations. Since species demonstrating contraction during daylight in the absence of current flow expanded their tentacles and polyps when subjected to high current flow, the need for feeding appears to be more important than predator avoidance in controlling expansion behaviour.

scholarly journals Simple Nomographs for Assessing Lighting in Urban Environments

2021 ◽  
Author(s):  
◽  
Tomas Sandoval-Calderon
Keyword(s):  
Energy Management ◽  
Large Scale ◽  
Early Stage ◽  
Lighting Design ◽  
Urban Environments ◽  
Design Parameters ◽  
Light Levels ◽  
Occupant Comfort ◽  
Good Energy ◽  
Selection Of

<p>Incorporating different technologies and lighting techniques in the illumination of structures has allowed us to portray fantastic night time vistas of our cities. However, the success of the selected technique or technology is frequently assessed based on what the lighting does to the overall environment. At present, it is a common practice for the client or architect to require an illuminated night view of the building. These views are often used as part of the marketing strategy to promote building facilities. Alternatively, on a large scale, they can help promote buildings as city icons.  The illumination of building facades requires an appropriate selection of one or more floodlighting techniques and light sources to achieve the desired lighting effect. This selection, often driven by lighting standards and design considerations, will heavily influence the way in which that the overall lit environment will be portrayed at the end of the lighting project. Currently, tables and floodlighting techniques exist to select the recommended quantity of light and the most suitable luminaire arrangement to illuminate a façade. There is however, no direct indication of how the surrounding area will be affected when the recommended light levels are achieved on the façade.  Despite the increased importance of the floodlighting technique, the design of a good illuminated façade does not have a tradition on which to base parameters for the lighting design. This is often individually approached based on the knowledge, understanding, experience and proficiency of the lighting designer. Considering the diversity of buildings in urban environments, the selection of uncoordinated design parameters could have a significant impact on the area where the building is located. This could affect the occupant comfort and good energy management.  In light of the considerations presented above, it is only with a methodological approach that the lighting designer will be able to provide predictable and consistent results in any number of different situations. This presents an opportunity to develop a methodology to identify whether a façade is over-lit or if the proposed lighting solution is adequate for the area where it is situated.  The proposed methodology will provide a tool to estimate the potential lighting results while considering the effect on the overall environment where the building is located. When a façade is illuminated, the degree of the light experienced at street level is very much dependent upon the reflected light from the primary lit surface. This allows for a relationship based on light levels received at the surrounding street and the average illuminance level achieved on the façade.  Considering that lighting parameters such as lamp lumen output, the reflective qualities of the surface and the luminaire position are intrinsically connected to light reflections, a mathematical expression is formulated to link the relationship mentioned above with lighting design parameters through a set of nomographs. This method provides a good foundation to systematically approach lighting designs with a comprehensive procedure to link the practical lighting considerations with the lighting requirements that will provide occupant comfort and good energy management. This method will help designers to compare different lighting alternatives by analysing the lighting impact of different lit facade options at the very early stage of the lighting design process.</p>

scholarly journals Local build-up of sleep pressure could trigger mind wandering: evidence from sleep, circadian and mind wandering research

2020 ◽  
Author(s):  
Esperanza Jubera-Garcia ◽  
wim gevers ◽  
Filip Van Opstal
Keyword(s):  
Task Performance ◽  
Mind Wandering ◽  
Time Of Day ◽  
Quality Of Sleep ◽  
Brain Areas ◽  
Brain States ◽  
Specific Factors ◽  
The Individual ◽  
The Brain

Mind wandering (MW) or having thoughts unrelated to the task at hand is a very pervasive phenomenon. Although research on MW has exponentially grown during the last decade and a half, the mechanisms behind this omnipresent phenomenon remain largely unknown. In this review, we will discuss some factors that have been shown to contribute to the occurrence of MW: the quality of sleep, the time of day when the task is performed, the chronotype of the individual and the duration of the task. The intriguing commonality between these specific factors is that they all suggest a relation between MW and “fatigued” brain states. This suggestion nicely fits a recent proposal that related MW to local “fatigued” brain areas involved in task performance. We will argue that one of the mechanisms underlying the pervasiveness of MW might be the local build-up of homeostatic sleep pressure that inevitably occurs during task performance in the brain areas related to the task.

scholarly journals Roadway Lighting’s Effect on Pedestrian Safety at Intersection and Midblock Crosswalks

2021 ◽  
Author(s):  
Rajaram Bhagavathula ◽  
◽  
Ronald Gibbons ◽  
Andrew Kassing ◽  
◽  
...  
Keyword(s):  
Pedestrian Detection ◽  
Positive Contrast ◽  
Pedestrian Safety ◽  
Light Level ◽  
Lighting Design ◽  
Visual Performance ◽  
Light Levels ◽  
Disability Glare ◽  
Safety Countermeasures ◽  
Pedestrian Crossing

This study evaluates the visual performance of four intersection lighting designs and five midblock crosswalk lighting designs along with two pedestrian safety countermeasures (rectangular rapid flashing beacons and flashing signs) at three light levels. The study involved a pedestrian detection task, which was completed at night on a realistic roadway intersection and a midblock crosswalk. The results from the study showed that driver nighttime visual performance at intersection and midblock crosswalks was influenced by the lighting design and light level. Intersections should be illuminated to an average horizontal illuminance of 14 lux (1.3 fc). This light level ensures optimal visibility of pedestrians regardless of the lighting design (or luminaire layout) of the intersection. The average horizontal illuminance of 14 lux (1.3 fc) also increases the visibility of pedestrians when glare from oncoming vehicles is present. The 14 lux (1.3 fc) average horizontal illuminance is valid for all lighting designs evaluated except the lighting design that illuminated the exits of the intersection. When the exits of the intersection are illuminated, an average horizontal illuminance of 24 lux (2.2 fc) is needed to offset the disability glare from opposing vehicles. Midblock crosswalks should be illuminated to an average vertical illuminance of 10 lux (0.9 fc) to ensure optimal pedestrian visibility. Where overhead lighting is available, midblock crosswalk lighting designs that render the pedestrian in positive contrast are recommended. Where overhead lighting is not available, crosswalk illuminators can be used to illuminate midblock crosswalks. At night, pedestrian crossing treatments such as rectangular rapid flashing beacons and flashing signs should not be used for pedestrian visibility at midblock crosswalks. Pedestrians crossing treatments should be used in conjunction with overhead lighting or crosswalk illuminators at the established vertical illuminance to ensure optimal pedestrian visibility at midblock crosswalks.

Time- and place-dependent experiences of loneliness in assisted living facilities

2019 ◽  
pp. 1-17 ◽  
Author(s):  
Anu H. Jansson ◽  
Antti Karisto ◽  
Kaisu H. Pitkälä
Keyword(s):  
Assisted Living ◽  
Mixed Method ◽  
Time Of Day ◽  
Abductive Reasoning ◽  
Assisted Living Facilities ◽  
Focus Group Interviews ◽  
Specific Factors ◽  
Care Practices ◽  
Group Interviews ◽  
Method Approach

AbstractThe purpose of the study is to explore feelings of loneliness among residents in assisted living facilities in terms of how loneliness is experienced and articulated, and what specific factors are related to the experiences. The study used a mixed-method approach. We individually interviewed 13 residents twice over six months. We conducted two focus group interviews and noted our observations each time we met the respondents. Data analysis leaned on abductive reasoning. The respondents described loneliness in versatile, rich ways. It proved to be time and place dependent. It was dependent on the time of day, days of the week and seasons. Lonely time was meaningless and filled with a feeling of waiting. Loneliness was also intertwined with place. None of the respondents called their apartment home; instead they called it a hospital, even a prison. They had to spend long periods of time in their apartments against their will, and their desire to interact with other residents was not met. The respondents felt invisible. Residents’ experiences of loneliness in assisted living facilities are unique and distinctive. Time- and place-dependent experiences of loneliness act as important signals for reflection on how care practices in these facilities could be more satisfying. Loneliness should therefore be a key topic and the target of prevention and interventions.

Conflicts and Consistencies in Creativity Research and Teaching

2018 ◽  
Vol 45 (4) ◽  
pp. 363-370 ◽  
Author(s):  
Mareike B. Wieth ◽  
Andrea P. Francis
Keyword(s):  
Domain Knowledge ◽  
Time Of Day ◽  
Research And Teaching ◽  
Creativity Research ◽  
Specific Factors ◽  
Everyday Creativity ◽  
The Difference ◽  
The Many ◽  
The Impact

The interdisciplinary topic of creativity is both fascinating and controversial. In this review, we begin by highlighting the many ways that researchers conceptualize and define creativity, focusing in particular on the difference between everyday creativity and creativity associated with exceptional breakthroughs in thinking. In addition, we discuss the role of divergent and convergent creativity and the role that domain knowledge plays in creativity. Furthermore, we highlight how specific factors such as individual differences and time of day influence creativity. We conclude by discussing the impact of current educational practices on creativity in psychology classrooms.

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