Multiobjective generalized extremal optimization algorithm for simulation of daylight illuminants
NASA Astrophysics Data System (ADS)
Kumar, Srividya Ravindra; Kurian, Ciji Pearl; Gomes-Borges, Marcos Eduardo
2017-10-01
Daylight illuminants are widely used as references for color quality testing and optical vision testing applications. Presently used daylight simulators make use of fluorescent bulbs that are not tunable and occupy more space inside the quality testing chambers. By designing a spectrally tunable LED light source with an optimal number of LEDs, cost, space, and energy can be saved. This paper describes an application of the generalized extremal optimization (GEO) algorithm for selection of the appropriate quantity and quality of LEDs that compose the light source. The multiobjective approach of this algorithm tries to get the best spectral simulation with minimum fitness error toward the target spectrum, correlated color temperature (CCT) the same as the target spectrum, high color rendering index (CRI), and luminous flux as required for testing applications. GEO is a global search algorithm based on phenomena of natural evolution and is especially designed to be used in complex optimization problems. Several simulations have been conducted to validate the performance of the algorithm. The methodology applied to model the LEDs, together with the theoretical basis for CCT and CRI calculation, is presented in this paper. A comparative result analysis of M-GEO evolutionary algorithm with the Levenberg-Marquardt conventional deterministic algorithm is also presented.
Reduction of lighting energy consumption in office buildings through improved daylight design
NASA Astrophysics Data System (ADS)
Papadouri, Maria Violeta Prado
This study aims to investigate the lighting energy consumption in office buildings and the options for its reduction. One way to reduce lighting energy consumption is by improving the daylight design. A better use of daylight in buildings might be an outcome from the effort made in different directions. Like the improvement of a building's fabric and layout, the materials, even the furniture in a space influences the daylight quality considerably. Also very important role in lighting energy consumption has the development of more efficient lighting technology like the electric lighting control systems, such as photo sensors and occupancy sensors. Both systems are responsible so that the electric light is not used without reason. As the focusing area of this study, is to find ways to improve the daylight use in buildings, a consequent question is which are the methods provided in order to achieve this The accuracy of the methodology used is also an important issue in order to achieve reliable results. The methodology applied in this study includes the analysis of a case study by taking field measurements and computer simulations. The first stage included gathering information about the lighting design of the building and monitoring the light levels, both from natural and from the electric lighting. The second stage involved testing with computer simulations, different parameters that were expected to improve the daylight exploitation of the specific area. The results of the field measurements showed that the main problems of the space were the low natural light levels and the poor daylight distribution. The annual electric lighting energy consumption, as it was calculated with the use of computer simulations, represented the annual energy consumption of a typical air-conditioned prestige office building (energy consumption guide 19, for energy use in offices, 2000). After several computer simulations, the results showed that initial design parameters of the building can affect the lighting energy consumption of the space significantly. On the other hand, relatively small changes, like changing the reflectance of the surfaces and the lighting control systems can make even more difference to the light quality of the space and the reduction of lighting energy consumption.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zuo, Wangda; McNeil, Andrew; Wetter, Michael
2013-05-23
Building designers are increasingly relying on complex fenestration systems to reduce energy consumed for lighting and HVAC in low energy buildings. Radiance, a lighting simulation program, has been used to conduct daylighting simulations for complex fenestration systems. Depending on the configurations, the simulation can take hours or even days using a personal computer. This paper describes how to accelerate the matrix multiplication portion of a Radiance three-phase daylight simulation by conducting parallel computing on heterogeneous hardware of a personal computer. The algorithm was optimized and the computational part was implemented in parallel using OpenCL. The speed of new approach wasmore » evaluated using various daylighting simulation cases on a multicore central processing unit and a graphics processing unit. Based on the measurements and analysis of the time usage for the Radiance daylighting simulation, further speedups can be achieved by using fast I/O devices and storing the data in a binary format.« less
Demonstration of a light-redirecting skylight system at the Palm Springs Chamber of Commerce
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, E.S.; Beltran, L.O.; Selkowitz, S.E.
1996-05-01
As part of a demonstration project to provide a comprehensive energy upgrade to a 294 m{sup 2} (3168 ft{sup 2}) commercial building, an advanced skylight design was developed using optical light control materials and geometry to provide daylight to two adjoining offices. The skylight system was developed using outdoor physical model tests and simulation tools Limited on-site measurements and occupant polls were conducted. Market issues were addressed. The skylight systems were found to improve lighting quality and to control excessive daylight illuminance levels compared to a conventional diffusing bubble skylight. Daylighting principles developed in earlier work for vertical glazing systemsmore » (light shelves and light pipes) were shown to be applicable in skylight designs at full-scale.« less
ERIC Educational Resources Information Center
Heschong, Lisa
This study examines the effect of daylighting on human performance, focusing on skylighting as a way to isolate daylight as an illumination source, and separate illumination effects from other qualities associated with daylighting from windows. It establishes a statistical connection between daylighting and student performance and between…
Artificial light sources for simulating natural daylight and skylight.
Grum, F
1968-01-01
A review of the literature reveals the need for reliable and stable artificial light sources that can be used as simulators of daylight and skylight. In quest of such simulators a first requirement is quantitative information on the average spectral distributions of natural sources such as daylight and skylight. Recent investigations of the spectral energy characteristics of natural daylight and skylight made it possible to determine such average conditions. With these conditions established, a search was undertaken for an artificial light source that would simulate these average natural distributions with a minimum of filtering. Certain fluorescent lamps and combinations of them were considered first, but, although it was possible to achieve fairly good visual matches of daylight and skylight, the spectral characteristics and the variability of such combinations are drawbacks to their use in critical scientific work. For this purpose, therefore, xenon arc lamps were found to be superior.
A Framework for Daylighting Optimization in Whole Buildings with OpenStudio
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2016-08-12
We present a toolkit and workflow for leveraging the OpenStudio (Guglielmetti et al. 2010) platform to perform daylighting analysis and optimization in a whole building energy modeling (BEM) context. We have re-implemented OpenStudio's integrated Radiance and EnergyPlus functionality as an OpenStudio Measure. The OpenStudio Radiance Measure works within the OpenStudio Application and Parametric Analysis Tool, as well as the OpenStudio Server large scale analysis framework, allowing a rigorous daylighting simulation to be performed on a single building model or potentially an entire population of programmatically generated models. The Radiance simulation results can automatically inform the broader building energy model, andmore » provide dynamic daylight metrics as a basis for decision. Through introduction and example, this paper illustrates the utility of the OpenStudio building energy modeling platform to leverage existing simulation tools for integrated building energy performance simulation, daylighting analysis, and reportage.« less
Energy and daylighting: A correlation between quality of light and energy consciousness
DOE Office of Scientific and Technical Information (OSTI.GOV)
Krug, N.
1997-12-31
Energy and Daylighting, an advanced topics graduate/professional elective has been established to help the student develop a deeper understanding of Architectural Daylighting, Energy Conserving Design, and Material/Construction/Methods through direct application. After a brief survey of the principles and applications of current and developing attitudes and techniques in energy conservation and natural lighting strategies is conducted (in order to build upon previous courses), an extensive exercise follows which allows the student the opportunity for direct applications. Both computer modeling/analysis and physical modeling (light box simulation with photographic documentation) are employed to focus attention on the interrelationships between natural lighting and passivemore » energy conserving design--all within the context of establishing environmental (interior) quality and (exterior) design direction. As a result, students broaden their understanding of natural light and energy conservation as design tools; the importance of environmental responsibility, both built and natural environments; and using computer analysis as a design tool. This presentation centers around the activities and results obtained from explorations into Energy and Daylighting. Discussion will highlight the course objectives, the methodology involved in the studies, specific requirements and means of evaluation, a slide show of befores and afters (results), and a retrospective look at the course`s value, as well as future directions and implications.« less
Simulating the energy performance of holographic glazings
NASA Astrophysics Data System (ADS)
Papamichael, K.; Beltran, L.; Furler, Reto; Lee, E. S.; Selkowitz, Steven E.; Rubin, Michael
1994-09-01
The light diffraction properties of holographic diffractive structures present an opportunity to improve the daylight performance in side-lit office spaces by redirecting and reflecting sunlight off the ceiling, providing adequate daylight illumination up to 30 ft (9.14 m) from the window wall. Prior studies of prototypical holographic glazings, installed above conventional `view' windows, have shown increased daylight levels over a deeper perimeter area than clear glass, for selected sun positions. In this study, we report on the simulation of the energy performance of prototypical holographic glazings assuming a commercial office building in the inland Los Angeles climate. The simulation of the energy performance involved determination of both luminous and thermal performance. Since the optical complexity of holographic glazings prevented the use of conventional algorithms for the simulation of their luminous performance, we used a newly developed method that combines experimentally determined directional workplane illuminance coefficients with computer-based analytical routines to determine a comprehensive set of daylight factors for many sun positions. These daylight factors were then used within the DOE-2.1D energy simulation program to determine hourly daylight and energy performance over the course of an entire year for four window orientations. Since the prototypical holographic diffractive structures considered in this study were applied on single pane clear glass, we also simulated the performance of hypothetical glazings, assuming the daylight performance of the prototype holographic glazings and the thermal performance of double-pane and low-e glazings. Finally, we addressed various design and implementation issues towards potential performance improvement.
Hybrid daylight/light-emitting diode illumination system for indoor lighting.
Ge, Aiming; Qiu, Peng; Cai, Jinlin; Wang, Wei; Wang, Junwei
2014-03-20
A hybrid illumination method using both daylight and light-emitting diodes (LEDs) for indoor lighting is presented in this study. The daylight can be introduced into the indoor space by a panel-integration system. The daylight part and LEDs are combined within a specific luminaire that can provide uniform illumination. The LEDs can be turned on and dimmed through closed-loop control when the daylight illuminance is inadequate. We simulated the illumination and calculated the indoor lighting efficiency of our hybrid daylight and LED lighting system, and compared this with that of LED and fluorescent lighting systems. Simulation results show that the efficiency of the hybrid daylight/LED illumination method is better than that of LED and traditional lighting systems, under the same lighting conditions and lighting time; the method has hybrid lighting average energy savings of T5 66.28%, and that of the LEDs is 41.62%.
ERIC Educational Resources Information Center
Kosik, Kenneth S.; Heschong, Lisa
An audiotape presents study analysis of the effect of daylighting on student performance. The study includes a focus on skylighting as a way to isolate daylight as an illumination source, and separate illumination effects from other qualities associated with daylighting from windows. Results from test scores of over 21,000 student records, along…
Effect of dividing daylight in symmetric prismatic daylight collector
NASA Astrophysics Data System (ADS)
Yeh, Shih-Chuan; Lu, Ju-Lin; Cheng, Yu-Chin
2017-04-01
This paper presented a symmetric prismatic daylight collector to collect daylight for the natural light illumination system. We analyzed the characteristics of the emerging light when the parallel light beam illuminate on the horizontally placed symmetric prismatic daylight collector. The ratio of the relative intensities of collected daylight that emerging from each surface of the daylight collector shown that the ratio is varied with the incident angle during a day. The simulation of the emerging light of the daylight collector shown that the ratio of emerging light is varied with the tilted angle when sunshine illuminated on a symmetric prismatic daylight collector which was not placed horizontally. The integration of normalized intensity is also varied with the tilted angle. The symmetric prismatic daylight collector with the benefits of reducing glare and dividing intensity of incident daylight, it is applicable to using in the natural light illumination system and hybrid system for improving the efficiency of utilizing of solar energy.
Hertog, W; Llenas, A; Carreras, J
2015-11-30
This article demonstrates the benefits of complementing a daylight-lit environment with a spectrally tunable illumination system. The spectral components of daylight present in the room are measured by a low-cost miniature spectrophotometer and processed through a number of optimization algorithms, carefully trading color fidelity for energy efficiency. Spectrally-tunable luminaires provide only those wavelengths that ensure that either the final illumination spectrum inside the room is kept constant or carefully follows the dynamic spectral pattern of natural daylight. Analyzing the measured data proves that such a hybrid illumination system brings both unprecendented illumination quality and significant energy savings.
ADASY (Active Daylighting System)
NASA Astrophysics Data System (ADS)
Vázquez-Moliní, Daniel; González-Montes, Mario; Fernández-Balbuena, Antonio Á.; Bernabéu, Eusebio; García-Botella, Ángel; García-Rodríguez, Lucas; Pohl, Wilfried
2009-08-01
The main objective of ADASY (Active Daylighting System) work is to design a façade static daylighting system oriented to office applications, mainly. The goal of the project is to save energy by guiding daylight into a building for lighting purpose. With this approach we can reduce the electrical load for artificial lighting, completing it with sustainable energy. The collector of the system is integrated on a vertical façade and its distribution guide is always horizontal inside of the false ceiling. ADASY is designed with a specific patent pending caption system, a modular light-guide and light extractor luminaire system. Special care has been put on the final cost of the system and its building integration purpose. The current ADASY configuration is able to illuminate 40 m2 area with a 300lx-400lx level in the mid time work hours; furthermore it has a good enough spatial uniformity distribution and a controlled glare. The data presented in this study are the result of simulation models and have been confirmed by a physical scaled prototype. ADASY's main advantages over regular illumination systems are: -Low maintenance; it has not mobile pieces and therefore it lasts for a long time and require little attention once installed. - No energy consumption; solar light continue working even if there has been a power outage. - High quality of light: the colour rendering of light is very high - Psychological benefits: People working with daylight get less stress and more comfort, increasing productivity. - Health benefits
Boubekri, Mohamed; Cheung, Ivy N.; Reid, Kathryn J.; Wang, Chia-Hui; Zee, Phyllis C.
2014-01-01
Study Objective: This research examined the impact of daylight exposure on the health of office workers from the perspective of subjective well-being and sleep quality as well as actigraphy measures of light exposure, activity, and sleep-wake patterns. Methods: Participants (N = 49) included 27 workers working in windowless environments and 22 comparable workers in workplaces with significantly more daylight. Windowless environment is defined as one without any windows or one where workstations were far away from windows and without any exposure to daylight. Well-being of the office workers was measured by Short Form-36 (SF-36), while sleep quality was measured by Pittsburgh Sleep Quality Index (PSQI). In addition, a subset of participants (N = 21; 10 workers in windowless environments and 11 workers in workplaces with windows) had actigraphy recordings to measure light exposure, activity, and sleep-wake patterns. Results: Workers in windowless environments reported poorer scores than their counterparts on two SF-36 dimensions—role limitation due to physical problems and vitality—as well as poorer overall sleep quality from the global PSQI score and the sleep disturbances component of the PSQI. Compared to the group without windows, workers with windows at the workplace had more light exposure during the workweek, a trend toward more physical activity, and longer sleep duration as measured by actigraphy. Conclusions: We suggest that architectural design of office environments should place more emphasis on sufficient daylight exposure of the workers in order to promote office workers' health and well-being. Citation: Boubekri M, Cheung IN, Reid KJ, Wang CH, Zee PC. Impact of windows and daylight exposure on overall health and sleep quality of office workers: a case-control pilot study. J Clin Sleep Med 2014;10(6):603-611. PMID:24932139
Daylighting Strategies Promote Healthy High Performance Buildings
ERIC Educational Resources Information Center
Gille, Steve
2010-01-01
There are many reasons to incorporate daylighting into the building or renovation of K-16 learning facilities. Benefits include increased productivity for students and staff, improved health, a better connection to the outdoors, energy savings and better quality of light. Add the role daylighting can play in LEED certification and it's clear that…
Hardware-in-the-Loop Modeling and Simulation Methods for Daylight Systems in Buildings
NASA Astrophysics Data System (ADS)
Mead, Alex Robert
This dissertation introduces hardware-in-the-loop modeling and simulation techniques to the daylighting community, with specific application to complex fenestration systems. No such application of this class of techniques, optimally combining mathematical-modeling and physical-modeling experimentation, is known to the author previously in the literature. Daylighting systems in buildings have a large impact on both the energy usage of a building as well as the occupant experience within a space. As such, a renewed interest has been placed on designing and constructing buildings with an emphasis on daylighting in recent times as part of the "green movement.''. Within daylighting systems, a specific subclass of building envelope is receiving much attention: complex fenestration systems (CFSs). CFSs are unique as compared to regular fenestration systems (e.g. glazing) in the regard that they allow for non-specular transmission of daylight into a space. This non-specular nature can be leveraged by designers to "optimize'' the times of the day and the days of the year that daylight enters a space. Examples of CFSs include: Venetian blinds, woven fabric shades, and prismatic window coatings. In order to leverage the non-specular transmission properties of CFSs, however, engineering analysis techniques capable of faithfully representing the physics of these systems are needed. Traditionally, the analysis techniques available to the daylighting community fall broadly into three classes: simplified techniques, mathematical-modeling and simulation, and physical-modeling and experimentation. Simplified techniques use "rules-of-thumb'' heuristics to provide insights for simple daylighting systems. Mathematical-modeling and simulation use complex numerical models to provide more detailed insights into system performance. Finally, physical-models can be instrumented and excited using artificial and natural light sources to provide performance insight into a daylighting system. Each class of techniques, broadly speaking however, has advantages and disadvantages with respect to the cost of execution (e.g. money, time, expertise) and the fidelity of the provided insight into the performance of the daylighting system. This varying tradeoff of cost and insight between the techniques determines which techniques are employed for which projects. Daylighting systems with CFS components, however, when considered for simulation with respect to these traditional technique classes, defy high fidelity analysis. Simplified techniques are clearly not applicable. Mathematical-models must have great complexity in order to capture the non-specular transmission accurately, which greatly limit their applicability. This leaves physical modeling, the most costly, as the preferred method for CFS. While mathematical-modeling and simulation methods do exist, they are in general costly and and still approximations of the underlying CFS behavior. Meaning in fact, measurements of CFSs are currently the only practical method to capture the behavior of CFSs. Traditional measurements of CFSs transmission and reflection properties are conducted using an instrument called a goniophotometer and produce a measurement in the form of a Bidirectional Scatter Distribution Function (BSDF) based on the Klems Basis. This measurement must be executed for each possible state of the CFS, hence only a subset of the possible behaviors can be captured for CFSs with continuously varying configurations. In the current era of rapid prototyping (e.g. 3D printing) and automated control of buildings including daylighting systems, a new analysis technique is needed which can faithfully represent these CFSs which are being designed and constructed at an increasing rate. Hardware-in-the-loop modeling and simulation is a perfect fit to the current need of analyzing daylighting systems with CFSs. In the proposed hardware-in-the-loop modeling and simulation approach of this dissertation, physical-models of real CFSs are excited using either natural or artificial light. The exiting luminance distribution from these CFSs is measured and used as inputs to a Radiance mathematical-model of the interior of the space, which is proposed to be lit by the CFS containing daylighting system. Hence, the components of the total daylighting and building system which are not mathematically-modeled well, the CFS, are physically excited and measured, while the components which are modeled properly, namely the interior building space, are mathematically-modeled. In order to excite and measure CFSs behavior, a novel parallel goniophotometer, referred to as the CUBE 2.0, is developed in this dissertation. The CUBE 2.0 measures the input illuminance distribution and the output luminance distribution with respect to a CFS under test. Further, the process is fully automated allowing for deployable experiments on proposed building sites, as well as in laboratory based experiments. In this dissertation, three CFSs, two commercially available and one novel--Twitchell's Textilene 80 Black, Twitchell's Shade View Ebony, and Translucent Concrete Panels (TCP)--are simulated on the CUBE 2.0 system for daylong deployments at one minute time steps. These CFSs are assumed to be placed in the glazing space within the Reference Office Radiance model, for which horizontal illuminance on a work plane of 0.8 m height is calculated for each time step. While Shade View Ebony and TCPs are unmeasured CFSs with respect to BSDF, Textilene 80 Black has been previously measured. As such a validation of the CUBE 2.0 using the goniophotometer measured BSDF is presented, with measurement errors of the horizontal illuminance between +3% and -10%. These error levels are considered to be valid within experimental daylighting investigations. Non-validated results are also presented in full for both Shade View Ebony as well as TCP. Concluding remarks and future directions for HWiL simulation close the dissertation.
Boubekri, Mohamed; Cheung, Ivy N; Reid, Kathryn J; Wang, Chia-Hui; Zee, Phyllis C
2014-06-15
This research examined the impact of daylight exposure on the health of office workers from the perspective of subjective well-being and sleep quality as well as actigraphy measures of light exposure, activity, and sleep-wake patterns. Participants (N = 49) included 27 workers working in windowless environments and 22 comparable workers in workplaces with significantly more daylight. Windowless environment is defined as one without any windows or one where workstations were far away from windows and without any exposure to daylight. Well-being of the office workers was measured by Short Form-36 (SF-36), while sleep quality was measured by Pittsburgh Sleep Quality Index (PSQI). In addition, a subset of participants (N = 21; 10 workers in windowless environments and 11 workers in workplaces with windows) had actigraphy recordings to measure light exposure, activity, and sleep-wake patterns. Workers in windowless environments reported poorer scores than their counterparts on two SF-36 dimensions--role limitation due to physical problems and vitality--as well as poorer overall sleep quality from the global PSQI score and the sleep disturbances component of the PSQI. Compared to the group without windows, workers with windows at the workplace had more light exposure during the workweek, a trend toward more physical activity, and longer sleep duration as measured by actigraphy. We suggest that architectural design of office environments should place more emphasis on sufficient daylight exposure of the workers in order to promote office workers' health and well-being.
Effect of extraoral aging conditions on mechanical properties of maxillofacial silicone elastomer.
Hatamleh, Muhanad M; Polyzois, Gregory L; Silikas, Nick; Watts, David C
2011-08-01
The purpose of this study was to investigate the effect of extraoral human and environmental conditions on the mechanical properties (tensile strength and modulus, elongation, tear strength hardness) of maxillofacial silicone elastomer. Specimens were fabricated using TechSil-S25 silicone elastomer (Technovent Ltd, Leeds, UK). Eight groups were prepared (21 specimens in each group; eight tensile, eight tear, five hardness) and conditioned differently as follows (groups 1 through 8): Dry storage for 24 hours; dry storage in dark for 6 months; storage in simulated sebum solution for 6 months; storage in simulated acidic perspiration for 6 months; accelerated artificial daylight aging under controlled moisture for 360 hours; outdoor weathering for 6 months; storage in antimicrobial silicone-cleaning solution for 30 hours; and mixed conditioning of sebum storage and light aging for 360 hours. The conditioning period selected simulated a prosthesis being in service for up to 12 months. Tensile and tear test specimens were fabricated and tested according to the International Standards Organization (ISO) standards no. 37 and 34, respectively. Shore A hardness test specimens were fabricated and tested according to the American Standards for Testing and Materials (ASTM) D 2240. Data were analyzed with one-way ANOVA, Bonferroni, and Dunnett's T3 post hoc tests (p < 0.05). Weibull analysis was also used for tensile strength and tear strength. Statistically significant differences were evident among all properties tested. Mixed conditioning of simulated sebum storage under accelerated artificial daylight aging significantly degraded mechanical properties of the silicone (p < 0.05). Mechanical properties of maxillofacial elastomers are adversely affected by human and environmental factors. Mixed aging of storage in simulated sebum under accelerated daylight aging was the most degrading regime. Accelerated aging of silicone specimens in simulated sebum under artificial daylight for 12 months of simulated clinical service greatly affected functional properties of silicone elastomer; however, in real practice, the effect is modest, since sebum concentration is lower, and daylight is less concentrated. © 2011 by The American College of Prosthodontists.
Minimizing lighting power density in office rooms equipped with Anidolic Daylighting Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Linhart, Friedrich; Scartezzini, Jean-Louis
2010-04-15
Electric lighting is responsible for up to one third of an office building's electricity needs. Making daylight more available in office buildings can not only contribute to significant energy savings but also enhance the occupants' performance and wellbeing. Anidolic Daylighting Systems (ADS) are one type of very effective facade-integrated daylighting systems. All south-facing office rooms within the LESO solar experimental building in Lausanne (Switzerland) are equipped with a given type of ADS. A recent study has shown that these offices' occupants are highly satisfied with their lighting environment. The most energy-efficient south-facing offices have a lighting power density of lessmore » than 5W/m{sup 2}. The lighting situation within these ''best practice''-offices has been assessed using the lighting simulation software RELUX Vision. Because this lighting situation is very much appreciated by the occupants, it was used as a starting point for developing even more energy-efficient office lighting designs. Two new lighting designs, leading to lighting power densities of 3.9W/m{sup 2} and 3W/m{sup 2}, respectively, have been suggested and simulated with RELUX Vision. Simulation results have shown that the expected performances of these new systems are comparable to that of the current lighting installation within the ''best practice''-offices or even better. These simulation results have been confirmed during experiments on 20 human subjects in a test office room recently set up within the LESO building. This article gives engineers, architects and light planers valuable information and ideas on how to design energy-efficient and comfortable electric lighting systems in office rooms with abundant access to daylight. (author)« less
Acceleration of Radiance for Lighting Simulation by Using Parallel Computing with OpenCL
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zuo, Wangda; McNeil, Andrew; Wetter, Michael
2011-09-06
We report on the acceleration of annual daylighting simulations for fenestration systems in the Radiance ray-tracing program. The algorithm was optimized to reduce both the redundant data input/output operations and the floating-point operations. To further accelerate the simulation speed, the calculation for matrix multiplications was implemented using parallel computing on a graphics processing unit. We used OpenCL, which is a cross-platform parallel programming language. Numerical experiments show that the combination of the above measures can speed up the annual daylighting simulations 101.7 times or 28.6 times when the sky vector has 146 or 2306 elements, respectively.
Microbiologic contamination during dental radiographic film processing.
Stanczyk, D A; Paunovich, E D; Broome, J C; Fatone, M A
1993-07-01
This study investigated microbiologic contamination of an automatic dental radiograph processor and daylight loader during a week of simulated clinical use. Pure cultures of Candida albicans, Streptococcus pneumoniae, Staphylococcus aureus, or Klebsiella pneumoniae were used to contaminate 320 vinyl intraoral radiograph packets. Each end of the films was deliberately contaminated during opening. These films and 24 uncontaminated control films were processed. Daylight loader ports, inlet and outlet rollers, fixer and developer samples, and 12 processed films were cultured daily. To simulate a weekend, the processor sites were cultured during 72 hours of inactivity after the contaminated runs. The results showed that contamination of the processor and daylight loader occurred and remained even after 48 hours of inactivity. Films remained contaminated after processing. In addition, cross-contamination of films occurred in the processor.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beltran, L.O.; Lee, E.S.; Papmichael, K.M.
1994-03-01
We present results from the design and evaluation of three advanced daylighting systems: a light shelf, a light pipe, and a skylight. These systems use optical films and an optimized geometry to passively intercept and redirect sunlight further into the building. The objectives of these designs are to increase daylighting illuminance levels at distances of 4.6-9.1 m (15--30 ft) from the window, and to improve the uniformity of the daylight distribution and the luminance gradient across the room under variable sun and sky conditions throughout the year. The designs were developed through a series of computer-assisted ray-tracing studies, photometric measurements,more » and observations using physical scale models. Comprehensive sets of laboratory measurements in combination with analytical routines were then used to simulate daylight performance for any solar position. Results show increased daylight levels and an improved luminance gradient throughout the year -- indicating that lighting energy consumption and cooling energy due of lighting can be substantially reduced with improvements to visual comfort. Future development of the designs may further improve the daylighting performance of these systems.« less
Modelling Complex Fenestration Systems using physical and virtual models
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thanachareonkit, Anothai; Scartezzini, Jean-Louis
2010-04-15
Physical or virtual models are commonly used to visualize the conceptual ideas of architects, lighting designers and researchers; they are also employed to assess the daylighting performance of buildings, particularly in cases where Complex Fenestration Systems (CFS) are considered. Recent studies have however revealed a general tendency of physical models to over-estimate this performance, compared to those of real buildings; these discrepancies can be attributed to several reasons. In order to identify the main error sources, a series of comparisons in-between a real building (a single office room within a test module) and the corresponding physical and virtual models wasmore » undertaken. The physical model was placed in outdoor conditions, which were strictly identical to those of the real building, as well as underneath a scanning sky simulator. The virtual model simulations were carried out by way of the Radiance program using the GenSky function; an alternative evaluation method, named Partial Daylight Factor method (PDF method), was also employed with the physical model together with sky luminance distributions acquired by a digital sky scanner during the monitoring of the real building. The overall daylighting performance of physical and virtual models were assessed and compared. The causes of discrepancies between the daylighting performance of the real building and the models were analysed. The main identified sources of errors are the reproduction of building details, the CFS modelling and the mocking-up of the geometrical and photometrical properties. To study the impact of these errors on daylighting performance assessment, computer simulation models created using the Radiance program were also used to carry out a sensitivity analysis of modelling errors. The study of the models showed that large discrepancies can occur in daylighting performance assessment. In case of improper mocking-up of the glazing for instance, relative divergences of 25-40% can be found in different room locations, suggesting that more light is entering than actually monitored in the real building. All these discrepancies can however be reduced by making an effort to carefully mock up the geometry and photometry of the real building. A synthesis is presented in this article which can be used as guidelines for daylighting designers to avoid or estimate errors during CFS daylighting performance assessment. (author)« less
Optimal integration of daylighting and electric lighting systems using non-imaging optics
NASA Astrophysics Data System (ADS)
Scartezzini, J.-L.; Linhart, F.; Kaegi-Kolisnychenko, E.
2007-09-01
Electric lighting is responsible for a significant fraction of electricity consumption within non-residential buildings. Making daylight more available in office and commercial buildings can lead as a consequence to important electricity savings, as well as to the improvement of occupants' visual performance and wellbeing. Over the last decades, daylighting technologies have been developed for that purpose, some of them having proven to be highly efficient such as anidolic daylighting systems. Based on non-imaging optics these optical devices were designed to achieve an efficient collection and redistribution of daylight within deep office rooms. However in order to benefit from the substantial daylight provision obtained through these systems and convert it into effective electricity savings, novel electric lighting strategies are required. An optimal integration of high efficacy light sources and efficient luminaries based on non-imaging optics with anidolic daylighting systems can lead to such novel strategies. Starting from the experience gained through the development of an Anidolic Integrated Ceiling (AIC), this paper presents an optimal integrated daylighting and electric lighting system. Computer simulations based on ray-tracing techniques were used to achieve the integration of 36W fluorescent tubes and non-imaging reflectors with an advanced daylighting system. Lighting power densities lower than 4 W/m2 can be achieved in this way within the corresponding office room. On-site monitoring of an integrated daylighting and electric lighting system carried out on a solar experimental building confirmed the energy and visual performance of such a system: it showed that low lighting power densities can be achieved by combining an anidolic daylighting system with very efficient electric light sources and luminaries.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Holder, L.M. III; Holder, L.M. IV
1999-07-01
The project was designed by the Overland Partners Architectural Firm for Riverbend Church of Austin as an Auditorium for Sunday Services and a venue for special theatrical presentations for the church and the community as well. It is an amphitheater on a hillside overlooking the Colorado River Valley. The amphitheater was selected as the building form to keep the audience closer to the speaker. A 175 ft wide by 60 ft tall arched window was installed on the north face to allow the audience to see the panorama views of the tree covered hills on the other side of themore » valley in the Texas Hill Country. Although the design is quite effective in achieving the program goals, these characteristics make it difficult to achieve effective daylighting without glare for the audience and television cameras since both face the north glazing. The design team was faced with providing quality daylighting for the audience and television cameras from the wall behind the stage. Most television studios have carefully controlled lighting systems with the major lighting component from behind the cameras. Virtually all television facilities with daylight contributing to the production lighting are in a building with high shading coefficient glass producing illumination on all areas equally or almost all glass and daylighting from skylights and clearstories above. All television networks have requirements for control of the quality of the video images to parallel those conditions for the program to be aired.« less
The integration of daylighting with artificial lighting to enhance building energy performance
NASA Astrophysics Data System (ADS)
Al-Ashwal, Najib Taher; Hassan, Ahmad Sanusi
2017-10-01
In sustainable building designs, daylight is considered as an alternative source of light to artificial lighting. Daylight is an energy-free and efficient-cost lighting source. Natural light is the best source for light due to its good quality, which matches the visual response of the human eyes. Daylight positively affects people by providing a sense of liveliness and brightness in the living space. The positive impact of daylight on the building occupants' visual comfort, health and performance is well recognized. However, daylight is not widely utilized to supplement artificial lighting, because there is a lack of information and tools to evaluate daylighting and potentials for energy savings. The efficient utilization of natural lighting will not only affect the interior environment and the occupants' health and performance but also has a direct impact on the building energy performance. Therefore, this paper reviews and discusses the effects of daylighting on the building energy performance mainly in schools and office buildings. This includes lighting energy performance, total energy consumption, cooling load. The methods, which are used to estimate the possible reduction in total energy consumption, are also reviewed in this research paper. Previous studies revealed that a clear reduction can be obtained in the energy consumed by electric lighting, as well as in the total energy end-use when a suitable lighting control system is applied to utilize the available natural light.
Daylight Saving Time Transitions and Road Traffic Accidents
Lahti, Tuuli; Nysten, Esa; Haukka, Jari; Sulander, Pekka; Partonen, Timo
2010-01-01
Circadian rhythm disruptions may have harmful impacts on health. Circadian rhythm disruptions caused by jet lag compromise the quality and amount of sleep and may lead to a variety of symptoms such as fatigue, headache, and loss of attention and alertness. Even a minor change in time schedule may cause considerable stress for the body. Transitions into and out of daylight saving time alter the social and environmental timing twice a year. According to earlier studies, this change in time-schedule leads to sleep disruption and fragmentation of the circadian rhythm. Since sleep deprivation decreases motivation, attention, and alertness, transitions into and out of daylight saving time may increase the amount of accidents during the following days after the transition. We studied the amount of road traffic accidents one week before and one week after transitions into and out of daylight saving time during years from 1981 to 2006. Our results demonstrated that transitions into and out of daylight saving time did not increase the number of traffic road accidents. PMID:20652036
Ambient air conditions and variation in urban trail use.
Holmes, Ann M; Lindsey, Greg; Qiu, Chenchen
2009-11-01
This study examines the effect of air quality and administrative policies on use of urban trails in Indianapolis, IN. Attention is focused on two policy variables: (1) issuance of air pollution advisories and (2) the adoption of Daylight Savings Time. Results suggest that while trail use varies with air quality, current public advisories regarding air pollution may be of limited effectiveness in reducing trail users' exposures to hazardous pollutants. In contrast, the adoption of Daylight Savings Time was associated with a statistically significant increase in traffic levels.
Arnold, Sarah E J; Chittka, Lars
2012-07-01
Patchy illumination presents foraging animals with a challenge, as the targets being sought may appear to vary in colour depending on the illumination, compromising target identification. We sought to explore how the bumblebee Bombus terrestris copes with tasks involving flower colour discrimination under patchy illumination. Light patches varied between unobscured daylight and leaf-shade, as a bee might encounter in and around woodland. Using a flight arena and coloured filters, as well as one or two different colours of artificial flower, we quantified how bees chose to forage when presented with foraging tasks under patchy illumination. Bees were better at discriminating a pair of similar colours under simulated unobscured daylight illumination than when foraging under leaf-shade illumination. Accordingly, we found that bees with prior experience of simulated daylight but not leaf-shade illumination initially preferred to forage in simulated daylight when all artificial flowers contained rewards as well as when only one colour was rewarding, whereas bees with prior experience of both illuminants did not exhibit this preference. Bees also switched between illuminants less than expected by chance. This means that bees prefer illumination conditions with which they are familiar, and in which rewarding flower colours are easily distinguishable from unrewarding ones. Under patchy illumination, colour discrimination performance was substantially poorer than in homogenous light. The bees' abilities at coping with patchy light may therefore impact on foraging behaviour in the wild, particularly in woodlands, where illumination can change over short spatial scales.
Light redirecting system using sine-wave based panels for dense urban areas
NASA Astrophysics Data System (ADS)
Mohamed, Mohamed W. N.; Mashaly, Islam A.; Mohamed, Osama N.; El-Henawy, Sally I.; Galal, Ola; Taha, Iman; Nassar, Khaled; Safwat, Amr M. E.
2014-09-01
Cities and towns around the world are becoming more condensed due to the shrinking amount of buildable areas, which significantly reduces the amount of light that occupants have access to. This lack of natural lighting results in health, safety and quality of life degradation. This paper presents a new technique of transmitting sunlight downward into narrow alleys and streets, by using a daylighting guiding acrylic panel that is capable of changing the direction and distribution of the incident light. The core of the proposed daylight guidance system is made up of light transmission panels with high quality. The corrugations have sine wave shaped cross-section so that the panel functions as an optical diffuser perpendicular to the direction of sunlight propagation. The day lighting system consists of the corrugated panels and a lattice frame, which supports the panel. The proposed system is to be mounted on the building roof facing the sun so as to redirect the incident sunlight downward into the narrow alleys or streets. Since building sizes and orientations are different the frame is arranged such that substantially deep light penetration and high luminance level can be achieved. Simulation results show that the proposed panel improves the illuminance values by more than 200% and 400% in autumn and winter, respectively, provides fan-out angle that exceeds 80° for certain solar altitudes and the transmitted power percentage varies from 40% to 90% as the solar altitude varies from 10° to 80°. Experimental results are in a good agreement with the simulations.
2009. Rob's areas of expertise are daylighting, physically based lighting simulation, the integration of lighting simulation with whole-building energy simulations, and high-dynamic range imaging. He has simulation, and high-dynamic range imaging. Rob is an advisory member of the Illuminating Engineering Society
Modified optical fiber daylighting system with sunlight transportation in free space.
Vu, Ngoc-Hai; Pham, Thanh-Tuan; Shin, Seoyong
2016-12-26
We present the design, optical simulation, and experiment of a modified optical fiber daylighting system (M-OFDS) for indoor lighting. The M-OFDS is comprised of three sub-systems: concentration, collimation, and distribution. The concentration part is formed by coupling a Fresnel lens with a large-core plastic optical fiber. The sunlight collected by the concentration sub-system is propagated in a plastic optical fiber and then collimated by the collimator, which is a combination of a parabolic mirror and a convex lens. The collimated beam of sunlight travels in free space and is guided to the interior by directing flat mirrors, where it is diffused uniformly by a distributor. All parameters of the system are calculated theoretically. Based on the designed system, our simulation results demonstrated a maximum optical efficiency of 71%. The simulation results also showed that sunlight could be delivered to the illumination destination at distance of 30 m. A prototype of the M-OFDS was fabricated, and preliminary experiments were performed outdoors. The simulation results and experimental results confirmed that the M-OFDS was designed effectively. A large-scale system constructed by several M-OFDSs is also proposed. The results showed that the presented optical fiber daylighting system is a strong candidate for an inexpensive and highly efficient application of solar energy in buildings.
Colorimetric analysis of outdoor illumination across varieties of atmospheric conditions.
Peyvandi, Shahram; Hernández-Andrés, Javier; Olmo, F J; Nieves, Juan Luis; Romero, Javier
2016-06-01
Solar illumination at ground level is subject to a good deal of change in spectral and colorimetric properties. With an aim of understanding the influence of atmospheric components and phases of daylight on colorimetric specifications of downward radiation, more than 5,600,000 spectral irradiance functions of daylight, sunlight, and skylight were simulated by the radiative transfer code, SBDART [Bull. Am. Meteorol. Soc.79, 2101 (1998)], under the atmospheric conditions of clear sky without aerosol particles, clear sky with aerosol particles, and overcast sky. The interquartile range of the correlated color temperatures (CCT) for daylight indicated values from 5712 to 7757 K among the three atmospheric conditions. A minimum CCT of ∼3600 K was found for daylight when aerosol particles are present in the atmosphere. Our analysis indicated that hemispheric daylight with CCT less than 3600 K may be observed in rare conditions in which the level of aerosol is high in the atmosphere. In an atmosphere with aerosol particles, we also found that the chromaticity of daylight may shift along the green-purple direction of the Planckian locus, with a magnitude depending on the spectral extinction by aerosol particles and the amount of water vapor in the atmosphere. The data analysis showed that an extremely high value of CCT, in an atmosphere without aerosol particles, for daylight and skylight at low sun, is mainly due to the effect of Chappuis absorption band of ozone at ∼600 nm. In this paper, we compare our data with well-known observations from previous research, including the ones used by the CIE to define natural daylight illuminants.
A sensor-less LED dimming system based on daylight harvesting with BIPV systems.
Yoo, Seunghwan; Kim, Jonghun; Jang, Cheol-Yong; Jeong, Hakgeun
2014-01-13
Artificial lighting in office buildings typically requires 30% of the total energy consumption of the building, providing a substantial opportunity for energy savings. To reduce the energy consumed by indoor lighting, we propose a sensor-less light-emitting diode (LED) dimming system using daylight harvesting. In this study, we used light simulation software to quantify and visualize daylight, and analyzed the correlation between photovoltaic (PV) power generation and indoor illumination in an office with an integrated PV system. In addition, we calculated the distribution of daylight illumination into the office and dimming ratios for the individual control of LED lights. Also, we were able directly to use the electric power generated by PV system. As a result, power consumption for electric lighting was reduced by 40 - 70% depending on the season and the weather conditions. Thus, the dimming system proposed in this study can be used to control electric lighting to reduce energy use cost-effectively and simply.
A spatially augmented reality sketching interface for architectural daylighting design.
Sheng, Yu; Yapo, Theodore C; Young, Christopher; Cutler, Barbara
2011-01-01
We present an application of interactive global illumination and spatially augmented reality to architectural daylight modeling that allows designers to explore alternative designs and new technologies for improving the sustainability of their buildings. Images of a model in the real world, captured by a camera above the scene, are processed to construct a virtual 3D model. To achieve interactive rendering rates, we use a hybrid rendering technique, leveraging radiosity to simulate the interreflectance between diffuse patches and shadow volumes to generate per-pixel direct illumination. The rendered images are then projected on the real model by four calibrated projectors to help users study the daylighting illumination. The virtual heliodon is a physical design environment in which multiple designers, a designer and a client, or a teacher and students can gather to experience animated visualizations of the natural illumination within a proposed design by controlling the time of day, season, and climate. Furthermore, participants may interactively redesign the geometry and materials of the space by manipulating physical design elements and see the updated lighting simulation. © 2011 IEEE Published by the IEEE Computer Society
NASA Astrophysics Data System (ADS)
Elayeb, O. K.; Alghoul, M. A.; Sopian, K.; Khrita, N. G.
2017-11-01
Despite Double skin façade (DSF) buildings are widely deployed worldwide, daylighting strategy is not commonly incorporated in these buildings compare to other strategies. Therefore, further theoretical and experimental studies would lead to adopting daylighting strategy in DSF office buildings. The aim of this study is to investigate the daylighting performance of office building at different design parameters of box window DSF using different glazing types under sub interval of intermediate sky conditions (20-40) klux using the (IES VE) simulation tool from Integrated Environmental Solutions - Virtual Environment. The implemented design parameters are window wall ratio (WWR) of internal façade (10-100) %, cavity depth (CD) of DSF (1-2.5) m and different glazing types. The glazing types were selected from the list available in the (IES VE) simulation tool. After series of evaluations, bronze tinted coating (STOPSOL) is implemented for the exterior façade while clear float, clear reflective coating (STOPSOL), grey and brown tinted coating (Anti-sun float) and blue coating tinted (SUNCOOL float) are implemented for the interior façade. In this paper, several evaluation parameters are used to quantify the optimum design parameters that would balance the daylighting requirements of a box window DSF office versus sky conditions range (20-40) klux. The optimum design parameters of DSF office building obtained under different glazing types are highlighted as follows. When using bronze tinted coating (STOPSOL) for the exterior façade, the glazing types of interior façade that showed superior daylighting performance of DSF office at (CD of 1.0m with WWR of 70%), (CD of 1.5m with WWR of 70%), (CD of 2.0m with WWR of 70%) and (CD of 2.0m with WWR of 70%) are grey tinted coating (Anti-sun float), clear reflective coating (STOPSOL), brown tinted coating (Anti-sun float), and clear float glazing respectively. Blue Coating tinted (SUNCOOL float) of interior façade glazing failed to meet outstanding daylighting performance at any cavity depth.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Geisler-Moroder, David; Lee, Eleanor S.; Ward, Gregory J.
2016-08-29
The Five-Phase Method (5-pm) for simulating complex fenestration systems with Radiance is validated against field measurements. The capability of the method to predict workplane illuminances, vertical sensor illuminances, and glare indices derived from captured and rendered high dynamic range (HDR) images is investigated. To be able to accurately represent the direct sun part of the daylight not only in sensor point simulations, but also in renderings of interior scenes, the 5-pm calculation procedure was extended. The validation shows that the 5-pm is superior to the Three-Phase Method for predicting horizontal and vertical illuminance sensor values as well as glare indicesmore » derived from rendered images. Even with input data from global and diffuse horizontal irradiance measurements only, daylight glare probability (DGP) values can be predicted within 10% error of measured values for most situations.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ward, Gregory; Mistrick, Ph.D., Richard; Lee, Eleanor
2011-01-21
We describe two methods which rely on bidirectional scattering distribution functions (BSDFs) to model the daylighting performance of complex fenestration systems (CFS), enabling greater flexibility and accuracy in evaluating arbitrary assemblies of glazing, shading, and other optically-complex coplanar window systems. Two tools within Radiance enable a) efficient annual performance evaluations of CFS, and b) accurate renderings of CFS despite the loss of spatial resolution associated with low-resolution BSDF datasets for inhomogeneous systems. Validation, accuracy, and limitations of the methods are discussed.
Building integrated semi-transparent photovoltaics: energy and daylighting performance
NASA Astrophysics Data System (ADS)
Kapsis, Konstantinos; Athienitis, Andreas K.
2011-08-01
This paper focuses on modeling and evaluation of semi-transparent photovoltaic technologies integrated into a coolingdominated office building façade by employing the concept of three-section façade. An energy simulation model is developed, using building simulation software, to investigate the effect of semi-transparent photovoltaic transmittance on the energy performance of an office in a typical office building in Montreal. The analysis is performed for five major façade orientations and two façade configurations. Using semi-transparent photovoltaic integrated into the office façade, electricity savings of up to 53.1% can be achieved compared to a typical office equipped with double glazing with Argon filling and a low emissivity coating, and lighting controlled based on occupancy and daylight levels.e.c
A Summary of Proceedings for the Advanced Deployable Day/Night Simulation Symposium
2009-07-01
initiated to design , develop, and deliver transportable visual simulations that jointly provide night-vision and high-resolution daylight capability. The...Deployable Day/Night Simulation (ADDNS) Technology Demonstration Project was initiated to design , develop, and deliver transportable visual...was Dr. Richard Wildes (York University); Mr. Vitaly Zholudev (Department of Computer Science, York University), Mr. X. Zhu (Neptec Design Group), and
NASA Astrophysics Data System (ADS)
Granderson, Jessica Ann
2007-12-01
The need for sustainable, efficient energy systems is the motivation that drove this research, which targeted the design of an intelligent commercial lighting system. Lighting in commercial buildings consumes approximately 13% of all the electricity generated in the US. Advanced lighting controls1 intended for use in commercial office spaces have proven to save up to 45% in electricity consumption. However, they currently comprise only a fraction of the market share, resulting in a missed opportunity to conserve energy. The research goals driving this dissertation relate directly to barriers hindering widespread adoption---increase user satisfaction, and provide increased energy savings through more sophisticated control. To satisfy these goals an influence diagram was developed to perform daylighting actuation. This algorithm was designed to balance the potentially conflicting lighting preferences of building occupants, with the efficiency desires of building facilities management. A supervisory control policy was designed to implement load shedding under a demand response tariff. Such tariffs offer incentives for customers to reduce their consumption during periods of peak demand, trough price reductions. In developing the value function occupant user testing was conducted to determine that computer and paper tasks require different illuminance levels, and that user preferences are sufficiently consistent to attain statistical significance. Approximately ten facilities managers were also interviewed and surveyed to isolate their lighting preferences with respect to measures of lighting quality and energy savings. Results from both simulation and physical implementation and user testing indicate that the intelligent controller can increase occupant satisfaction, efficiency, cost savings, and management satisfaction, with respect to existing commercial daylighting systems. Several important contributions were realized by satisfying the research goals. A general model of a daylighted environment was designed, and a practical means of user preference identification was defined. Further, a set of general procedures were identified for the design of human-centered sensor-based decision-analytic systems, and for the identification of the allowable uncertainty in nodes of interest. To confirm generality, a vehicle health monitoring problem was defined and solved using these two procedures. 1'Daylighting' systems use sensors to determine room occupancy and available sunlight, and automatically dim the lights in response.
What's crucial in night vision goggle simulation?
NASA Astrophysics Data System (ADS)
Kooi, Frank L.; Toet, Alexander
2005-05-01
Training is required to correctly interpret NVG imagery. Training night operations with simulated intensified imagery has great potential. Compared to direct viewing with the naked eye, intensified imagery is relatively easy to simulate and the cost of real NVG training is high (logistics, risk, civilian sleep deprivation, pollution). On the surface NVG imagery appears to have a structure similar to daylight imagery. However, in actuality its characteristics differ significantly from those of daylight imagery. As a result, NVG imagery frequently induces visual illusions. To achieve realistic training, simulated NVG imagery should at least reproduce the essential visual limitations of real NVG imagery caused by reduced resolution, reduced contrast, limited field-of-view, the absence of color, and the systems sensitivity to nearby infrared radiation. It is particularly important that simulated NVG imagery represents essential NVG visual characteristics, such as the high reflection of chlorophyll and halos. Current real-time simulation software falls short for training purposes because of an incorrect representation of shadow effects. We argue that the development of shading and shadowing merits priority to close the gap between real and simulated NVG flight conditions. Visual conspicuity can be deployed as an efficient metric to measure the 'perceptual distance' between the real NVG and the simulated NVG image.
Pearce, Bradley; Crichton, Stuart; Mackiewicz, Michal; Finlayson, Graham D; Hurlbert, Anya
2014-01-01
The phenomenon of colour constancy in human visual perception keeps surface colours constant, despite changes in their reflected light due to changing illumination. Although colour constancy has evolved under a constrained subset of illuminations, it is unknown whether its underlying mechanisms, thought to involve multiple components from retina to cortex, are optimised for particular environmental variations. Here we demonstrate a new method for investigating colour constancy using illumination matching in real scenes which, unlike previous methods using surface matching and simulated scenes, allows testing of multiple, real illuminations. We use real scenes consisting of solid familiar or unfamiliar objects against uniform or variegated backgrounds and compare discrimination performance for typical illuminations from the daylight chromaticity locus (approximately blue-yellow) and atypical spectra from an orthogonal locus (approximately red-green, at correlated colour temperature 6700 K), all produced in real time by a 10-channel LED illuminator. We find that discrimination of illumination changes is poorer along the daylight locus than the atypical locus, and is poorest particularly for bluer illumination changes, demonstrating conversely that surface colour constancy is best for blue daylight illuminations. Illumination discrimination is also enhanced, and therefore colour constancy diminished, for uniform backgrounds, irrespective of the object type. These results are not explained by statistical properties of the scene signal changes at the retinal level. We conclude that high-level mechanisms of colour constancy are biased for the blue daylight illuminations and variegated backgrounds to which the human visual system has typically been exposed.
Zadeh, Rana Sagha; Shepley, Mardelle McCuskey; Williams, Gary; Chung, Susan Sung Eun
2014-01-01
To investigate the physiological and psychological effects of windows and daylight on registered nurses. To date, evidence has indicated that appropriate environmental lighting with characteristics similar to natural light can improve mood, alertness, and performance. The restorative effects of windows also have been documented. Hospital workspaces generally lack windows and daylight, and the impact of the lack of windows and daylight on healthcare employees' well being has not been thoroughly investigated. Data were collected using multiple methods with a quasi-experimental approach (i.e., biological measurements, behavioral mapping, and analysis of archival data) in an acute-care nursing unit with two wards that have similar environmental and organizational conditions, and similar patient populations and acuity, but different availability of windows in the nursing stations. Findings indicated that blood pressure (p < 0.0001) decreased and body temperature increased (p = 0.03). Blood oxygen saturation increased (p = 0.02), but the difference was clinically insignificant. Communication (p < 0.0001) and laughter (p = 0.03) both increased, and the subsidiary behavior indicators of sleepiness and deteriorated mood (p = 0.02) decreased. Heart rate (p = 0.07), caffeine intake (p = 0.3), self-reported sleepiness (p = 0.09), and the frequency of medication errors (p = 0.14) also decreased, but insignificantly. The findings support evidence from laboratory and field settings of the benefits of windows and daylight. A possible micro-restorative effect of windows and daylight may result in lowered blood pressure and increased oxygen saturation and a positive effect on circadian rhythms (as suggested by body temperature) and morning sleepiness. Critical care/intensive care, lighting, nursing, quality care, work environment.
NASA Astrophysics Data System (ADS)
Cárdenas, J.; Osma, G.; Caicedo, C.; Torres, A.; Sánchez, S.; Ordóñez, G.
2016-07-01
This research shows the energy analysis of the Electrical Engineering Building, located on campus of the Industrial University of Santander in Bucaramanga - Colombia. This building is a green pilot for analysing energy saving strategies such as solar pipes, green roof, daylighting, and automation, among others. Energy analysis was performed by means of DesignBuilder software from virtual model of the building. Several variables were analysed such as air temperature, relative humidity, air velocity, daylighting, and energy consumption. According to two criteria, thermal load and energy consumption, critical areas were defined. The calibration and validation process of the virtual model was done obtaining error below 5% in comparison with measured values. The simulations show that the average indoor temperature in the critical areas of the building was 27°C, whilst relative humidity reached values near to 70% per year. The most critical discomfort conditions were found in the area of the greatest concentration of people, which has an average annual temperature of 30°C. Solar pipes can increase 33% daylight levels into the areas located on the upper floors of the building. In the case of the green roofs, the simulated results show that these reduces of nearly 31% of the internal heat gains through the roof, as well as a decrease in energy consumption related to air conditioning of 5% for some areas on the fourth and fifth floor. The estimated energy consumption of the building was 69 283 kWh per year.
ERIC Educational Resources Information Center
Kennedy, Mike
2002-01-01
Reviews ways that schools can provide effective indoor learning environments by paying attention to the following areas: daylighting, acoustics, space allocation, technology implementation, ergonomics, maintenance, indoor air quality, safety, restrooms, and roofing. (GR)
Use of Daylight and Aesthetic Image of Glass Facades in Contemporary Buildings
NASA Astrophysics Data System (ADS)
Roginska-Niesluchowska, Malgorzata
2017-10-01
The paper deals with the architecture of contemporary buildings in respect to their aesthetic image created by the use of natural light. Sustainability is regarded as a governing principle of contemporary architecture, where daylighting is an important factor as it affects energy consumption and environmental quality of the space inside a building. Environmental awareness of architecture, however, involves a much wider and more holistic view of design. The quality of sustainable architecture can be considered in its aesthetic and cultural context with regard to landscape, local tradition, and connection to the surrounding world. This approach is associated with the social mission of architecture, i.e. providing appropriate space for living, facilitating social relations and having positive impact on people. The purpose of the research is to study the use of daylight in creating an aesthetic image of contemporary buildings. The author focuses mainly on public buildings largely dedicated to art and culture which satisfy high functional and aesthetic requirements. The paper examines the genesis and current trends in the aesthetic image of modern buildings which use daylight as the main design strategy, focusing on the issues of glass facades. The main attention is given to the shaping of representative public areas which feature the glass facades. The research has been based on a case study, critical review of literature review, observation and synthesis. The study identifies and classifies different approaches to using daylight in these areas and highlights changes in the aesthetics of architecture made of glass, which uses daylight as the main design strategy. These changes are primarily caused by the development and spreading of new glazing materials and the use of digital method of design. The influence of light and its mode depends on glass materials but also on the local conditions of the site, and has a significant impact on the relationship between architecture and its natural and cultural environment. The subordination of architectural concept to the idea of natural lighting builds the relationship between form, function and the context of architecture, and is expressed in its structural, material and spatial properties, and in the resulting aesthetic order. Search for new architectural solutions is defined by local topographical, climatic, biological and cultural conditions. The architecture subordinate to the conception of contribution of light corresponds to the aesthetic aspirations of sustainability.
Nakajima, T Y; Imai, T; Uchino, O; Nagai, T
1999-08-20
The influence of daylight and noise current on cloud and aerosol observations by realistic spaceborne lidar was examined by computer simulations. The reflected solar radiations, which contaminate the daytime return signals of lidar operations, were strictly and explicitly estimated by accurate radiative transfer calculations. It was found that the model multilayer cirrus clouds and the boundary layer aerosols could be observed during the daytime and the nighttime with only a few laser shots. However, high background noise and noise current make it difficult to observe volcanic aerosols in middle and upper atmospheric layers. Optimal combinations of the laser power and receiver field of view are proposed to compensate for the negative influence that is due to these noises. For the computer simulations, we used a realistic set of lidar parameters similar to the Experimental Lidar in-Space Equipment of the National Space Development Agency of Japan.
Pearce, Bradley; Crichton, Stuart; Mackiewicz, Michal; Finlayson, Graham D.; Hurlbert, Anya
2014-01-01
The phenomenon of colour constancy in human visual perception keeps surface colours constant, despite changes in their reflected light due to changing illumination. Although colour constancy has evolved under a constrained subset of illuminations, it is unknown whether its underlying mechanisms, thought to involve multiple components from retina to cortex, are optimised for particular environmental variations. Here we demonstrate a new method for investigating colour constancy using illumination matching in real scenes which, unlike previous methods using surface matching and simulated scenes, allows testing of multiple, real illuminations. We use real scenes consisting of solid familiar or unfamiliar objects against uniform or variegated backgrounds and compare discrimination performance for typical illuminations from the daylight chromaticity locus (approximately blue-yellow) and atypical spectra from an orthogonal locus (approximately red-green, at correlated colour temperature 6700 K), all produced in real time by a 10-channel LED illuminator. We find that discrimination of illumination changes is poorer along the daylight locus than the atypical locus, and is poorest particularly for bluer illumination changes, demonstrating conversely that surface colour constancy is best for blue daylight illuminations. Illumination discrimination is also enhanced, and therefore colour constancy diminished, for uniform backgrounds, irrespective of the object type. These results are not explained by statistical properties of the scene signal changes at the retinal level. We conclude that high-level mechanisms of colour constancy are biased for the blue daylight illuminations and variegated backgrounds to which the human visual system has typically been exposed. PMID:24586299
Stapanian, Martin A.; Kocovsky, Patrick M.; Adams, Jean V.
2009-01-01
1. Non-native mussels have increased water clarity in many lakes and streams in North America and Europe. Diel variation in catchability of some fish species has been linked to visibility during survey trawls (used to measure escapement). 2. Water clarity increased in nearshore areas of western Lake Erie by the early 1990s, following passage of legislation in 1972 to improve water quality (e.g. reduce phosphorus loading) and the invasion of dreissenid mussels (Dreissena spp.) beginning in 1987. 3. We hypothesised that increased water clarity in Lake Erie resulted in decreased catchability of young-of-year (age-0) yellow perch (Perca flavescens Mitchill) during daylight compared to during night. We used a two-tiered modelling approach to test this hypothesis on the ratio (R) of catch per hour (CPH) during night to CPH during daylight in bottom trawl surveys conducted during 1961-2005. 4. First, we examined seven a priori models. The first model, the 'null' model, represented no change in R over time. Three more models tested whether the timing of the change in R was associated with passage of water quality legislation only, dreissenids only (two-period models) and both legislation and dreissenids (three-period models). Three additional models included a 3-year lag before the effects of legislation, dreissenids or both occurred. Secondly, all possible two- and three-period models with a minimum of 2 years per time period were explored a posteriori. The a posteriori procedure determined the temporal transitions to higher R that were best supported by the data, without regard to a priori hypotheses. 5. Night CPH was greater than daylight CPH in 3 of 11 years during 1961-72, in 10 of 15 years during 1973-87, and in 14 of 18 years during 1988-2005. During 1991-2005 night CPH exceeded daylight CPH in all years except one, and night CPH was more than twice daylight CPH in 10 years during this period. 6. The best a priori model had two periods, with a break between 1990 and 1991, corresponding to 3 years after the dreissenid invasion. Similarly, the best two- and three-period a posteriori models both had breaks between 1990 and 1991. The results supported our hypothesis that age-0 yellow perch exhibited a transition to lower catchability during daylight compared to night, and the timing of the transition coincided with the establishment of dreissenid mussels. 7. The most plausible mechanism for our results was increased visibility of the trawl during daylight, resulting in increased avoidance of the trawl. These results have potential applications wherever non-native mussels have increased water clarity.
78 FR 23896 - Notice of Funds Availability: Inviting Applications for the Quality Samples Program
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-23
... proposals for the 2014 Quality Samples Program (QSP). The intended effect of this notice is to solicit... (FAS). DATES: To be considered for funding, applications must be received by 5 p.m. Eastern Daylight... still available. FOR FURTHER INFORMATION CONTACT: Entities wishing to apply for funding assistance...
77 FR 24166 - Notice of Funds Availability; Inviting Applications for the Quality Samples Program
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-23
... proposals for the 2013 Quality Samples Program (QSP). The intended effect of this notice is to solicit... considered for funding, applications must be received by 5 p.m. Eastern Daylight Time, May 21, 2012. Any... INFORMATION CONTACT: Entities wishing to apply for funding assistance should contact the Program Operations...
ERIC Educational Resources Information Center
Kennedy, Mike
2003-01-01
Offers ten suggestions for schools and universities to help maintain a healthy indoor environment: proper flooring, sanitary washrooms, consistent maintenance, indoor air quality, preventing mold, daylighting, good acoustics, avoiding volatile organic compounds (VOCs), ergonomic furniture, and well-maintained roofs. (EV)
Sleep and chronobiology in cluster headache.
Barloese, M; Lund, N; Petersen, A; Rasmussen, M; Jennum, P; Jensen, R
2015-10-01
Cluster headache (CH) is the headache disorder with the strongest chronobiological traits. The severe attacks of pain occur with diurnal and annual rhythmicity but the precise rhythm and involvement of potential zeitgebers is unknown. Patients complain of poor sleep quality yet this has never been studied. We investigated triggers, rhythms, sleep quality and chronotypes in CH. Patients and controls completed questionnaires and structured interviews composed of new and previously validated parts including the Pittsburgh Sleep Quality Index (PSQI) and Morningness-Eveningness Questionnaire (MEQ). Patients were characterized by a CH index, a unified measure of headache burden. A total of 275 CH patients and 145 matched controls were included. The most common trigger was sleep (80%) and a relationship between clusters and daylight was identified. Of the patients, 82.2% reported diurnal and 56% annual rhythmicity. Patients reported impaired sleep quality (PSQI) (p < 0.0001) and an inverse relationship between time passed since last attack and sleep quality was identified (p < 0.0001). The CH index was positively related to the PSQI (p < 0.0001). Diurnally, CH exhibits a relationship with night-time and annually with daylight hours. Patients' sleep quality is reduced compared with controls. Results suggest a complex relationship as sleep quality improves between clusters, but remains pathological. © International Headache Society 2015.
Growth/reflectance model interface for wheat and corresponding model
NASA Technical Reports Server (NTRS)
Suits, G. H.; Sieron, R.; Odenweller, J.
1984-01-01
The use of modeling to explore the possibility of discovering new and useful crop condition indicators which might be available from the Thematic Mapper and to connect these symptoms to the biological causes in the crop is discussed. A crop growth model was used to predict the day to day growth features of the crop as it responds biologically to the various environmental factors. A reflectance model was used to predict the character of the interaction of daylight with the predicted growth features. An atmospheric path radiance was added to the reflected daylight to simulate the radiance appearing at the sensor. Finally, the digitized data sent to a ground station were calculated. The crop under investigation is wheat.
Moving into the Light: The AEOS Telescope in the Daytime Operating Environment
NASA Astrophysics Data System (ADS)
Mayo, J.
Abstract for Coming into the Light: The AEOS Telescope in the Daytime Operating Environment” Interest in daylight operation for the AEOS 3.67-m Telescope first surfaced during the preparation of the AEOS specification documentation in 1991. The author and Lt Rich Elder prepared, edited and combined requirements inputs from AFRL technical staff to create the final RFP document. In this released specification, AEOS daylight performance was limited to best effort, although provisions for adding secondary mirror sky light baffling were to be provided. In 1993, during the AEOS construction phase, AFRL requested that the author prepare a report on special considerations for operating AEOS in the solar illuminated daytime environment. This report was published and briefed to AFRL and Space Command at that time. Interest in this topic at AMOS was rekindled in 2007 by Dr Joe Janni and Lt Col Scott Hunt. The author updated his 1993 report and in June 2007 presented AEOS 1993 Daylight Operation Study Revisited” at AMOS. Subsequently, Dr Stacie Williams spearheaded additional work in this critical technical area. Recent efforts at Tau Technologies LLC have focused on external AEOS telescope baffling and shielding options assessment, solar irradiation effects on optical components, especially the primary mirror, and on modeling the solar illumination on the entire telescope during daylight operation. Solid Works and Illustrator simulation models have been developed and exercised.
ERIC Educational Resources Information Center
Gleed, Amy Keller
2009-01-01
Daylighting a space is both an art and a science. The impact of daylight can make a building's design come to life. Daylighting can be carried out skillfully, or it can be too casually considered or totally misunderstood. Bad daylighting is devastating to a space and costly to fix. Today, in this era of sustainable design, daylighting is given…
Energy performance and savings potentials with skylights
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arasteh, D.; Johnson, R.; Selkowitz, S.
1984-12-01
This study systematically explores the energy effects of skylight systems in a prototypical office building module and examines the savings from daylighting. For specific climates, roof/skylight characteristics are identified that minimize total energy or peak electrical demand. Simplified techniques for energy performance calculation are also presented based on a multiple regression analysis of our data base so that one may easily evaluate daylighting's effects on total and component energy loads and electrical peaks. This provides additional insights into the influence of skylight parameters on energy consumption and electrical peaks. We use the DOE-2.1B energy analysis program with newly incorporated daylightingmore » algorithms to determine hourly, monthly, and annual impacts of daylighting strategies on electrical lighting consumption, cooling, heating, fan power, peak electrical demands, and total energy use. A data base of more than 2000 parametric simulations for 14 US climates has been generated. Parameters varied include skylight-to-roof ratio, shading coefficient, visible transmittance, skylight well light loss, electric lighting power density, roof heat transfer coefficient, and electric lighting control type. 14 references, 13 figures, 4 tables.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-30
... Production Act of 1993--OpenDaylight Project, Inc. Notice is hereby given that, on November 13, 2013.... 4301 et seq. (``the Act''), OpenDaylight Project, Inc. (``OpenDaylight'') has filed written.... Membership in this group research project remains open, and OpenDaylight intends to file additional written...
Improving daylight in mosques using domes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alturki, I.; Schiler, M.; Boyajian, Y.
1996-10-01
This paper studies the possibilities for improving daylight in mosques by measuring the illumination level under various domes in an old mosque ``Mosque of Guzelce Hasan Bey in Hayrabolu`` using an architectural physical model. The illumination level under the domes were tested under three different cases: a dome without openings (the original building), a dome with a central opening, and a dome with openings around the base. It was found that a dome with openings around the base brings an evenly distributed light all over the prayer hall during the critical hours of 12:00 p.m. and 3:00 p.m. In addition,more » it improves the quality and quantity of light.« less
Daylighting as a design and energy strategy: Overview of opportunities and conflicts
NASA Astrophysics Data System (ADS)
Selkowitz, S.
1981-06-01
The potentials and problems associated with using daylight both to improve visual performance and interior aesthetics and to reduce electrical lighting energy consumption and peak electric loads are reviewed. Use of daylighting as a design strategy is not always synonymous with effective use of daylighting as an energy-saving strategy unless both approaches are jointly pursued by the design team. Criteria for visual performance, disability and discomfort glare, historical perspectives on daylight utilization, building form as a limit to daylight penetration, beam sunlighting strategies, luminous efficacy of daylight versus efficient electric light sources, comparative thermal impacts, peak load and load management potential, and nonenergy benefits are reviewed. Although the energy benefits of daylighting can be oversold, it is concluded that in most cases a solid understanding of the energy and design issues should produce energy efficiency and pleasing working environments.
Skylight energy performance and design optimization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arasteh, D.; Johnson, R.; Selkowitz, S.
1984-02-01
Proper skylight utilization can significantly lower energy requirements and peak electrical loads for space conditioning and lighting in commercial buildings. In this study we systematically explore the energy effects of skylight systems in a prototypical office building and examine the savings from daylighting. The DOE-2.1B energy analysis computer program with its newly incorporated daylighting algorithms was used to generate more than 2000 parametric simulations for seven US climates. The parameters varied include skylight-to-roof ratio, shading coefficient, visible transmittance, skylight well light loss, electric lighting power density, roof heat transfer coefficient, and type of electric lighting control. For specific climates wemore » identify roof/skylight characteristics that minimize total energy or peak electrical load requirements.« less
Essence of Daylight in the Cistercian Monastic Church of S. Bento de Cástris, Évora, Portugal
NASA Astrophysics Data System (ADS)
Martins, Ana M. T.; Carlos, Jorge S.
2017-10-01
Natural light in the Cistercian churches is closely linked not only with the liturgical requirements at the “officium” but also with the canonical hours based on the "ora et labora" dictated by the Rule of St. Benedict. The Cistercian architecture, in its beginnings (12th century forward) is characterized by austerity, simplicity and the play of light and shadow that gives value to the monastic architectural space itself, making it perfect for a contemplative experience. In the Cistercian Monastery the church is the central piece of the monastic building. Nave, transept and apse are the main architectural components to which is added the choir. This paper contextualizes the importance and close connections of natural light, within the Cistercian Monasteries architecture. Thus the essence of daylight is analysed within the Church of the Monastery of S. Bento de Cástris, in Évora, Portugal. This former Monastery (13th - 19th centuries) includes the church, at the south-eastern corner which has not only a high choir, but also a low lateral choir (within the presbytery). Its unchanged exterior walls are made of solid masonry. Although the function of the walls is primarily structural, the windows allow the daylight to penetrate the space of the church. The church has two external façades facing northeast and southeast. The combined orientation effect of the church’s main axis and the sun trajectory determines how the sunlight reaches the interior of this architectural structure. This study presents the qualitative and quantitative analysis of the luminous environment in the church of S. Bento de Cástris, being the first based on the authors’ perception of the effect of the daylight within the different areas of the enclosed space. The appreciation of the spatial experiences was supported by quantitative daylight simulations that were conducted in selected areas within the space. With this paper is intended to contribute to the debate about the specificity of daylight, in the context of Cistercian architecture.
Rosenberg, Michael; Wood, Lisa
2010-02-01
To measure the impact of the introduction of daylight saving in Western Australia in December 2006 on when during the day adults engaged in physical activity. In early December 2006, 1,300 Western Australian adults were telephoned and asked about how the introduction of daylight saving would influence when during the day they typically engaged in physical activity. At the end of the daylight saving period in March 2007, 1,083 of the baseline cohort agreed to answer questions relating to how daylight saving had affected when during the day they were physically active. Almost half the cohort (45.5%) reported that daylight saving had affected when during the day they were physically active. During daylight saving fewer people exercised in the morning and more people exercised in the evening. When analysed at the individual level, 23% of the cohort ceased to exercise in the morning during daylight saving and 22% exercised in the evening only during daylight saving. In addition, to changes in when during the day people exercised, there was also an overall reduction in the average number of daily exercise sessions, with 8% not exercising at all during daylight saving. The results suggest that the introduction of daylight saving, a relatively modest compulsory change to increase daylight by one hour had an impact on patterns of when during the day people were physically active. The study results reinforce the value of focusing on policy as an effective means of supporting population behaviour change. © 2010 The Authors. Journal Compilation © 2010 Public Health Association of Australia.
NASA Technical Reports Server (NTRS)
Kidder, Stanley Q.; Hafner, Jan
1997-01-01
The goal of Project ATLANTA is to derive a better scientific understanding of how land cover changes associated with urbanization affect local and regional climate and air quality. Clouds play a significant role in this relationship. Using GOES images, we found that in a 63-day period (5 July-5 September 1996) there were zero days which were clear for the entire daylight period. Days which are cloud-free in the morning become partly cloudy with small cumulus clouds in the afternoon in response to solar heating. This result casts doubt on the applicability of California-style air quality models which run in perpetual clear skies. Days which are clear in the morning have higher ozone than those which are cloudy in the morning. Using the RAMS model, we found that urbanization increases the skin surface temperature by about 1.0-1.5 C on average under cloudy conditions, with an extreme of +3.5 C. Clouds cool the surface due to their shading effect by 1.5-2.0 C on average, with an extreme of 5.0 C. RAMS simulates well the building stage of the cumulus cloud field, but does poorly in the decaying phase. Next year's work: doing a detailed cloud climatology and developing improved RAMS cloud simulations.
From dark to bright: novel daylighting applications in solid state lighting
NASA Astrophysics Data System (ADS)
Adler, Helmar G.
2011-10-01
The term "daylighting" is used in various ways, on one hand in a more architectural sense, i.e. using existing daylight to illuminate spaces, and on the other, more recently, for using light sources to replicate daylight. The emergence of solid state lighting (SSL) opens up a large number of new avenues for daylighting. SSL allows innovative controllability of intensity and color for artificial light sources that can be advantageously applied to daylighting. With the assistance of these new technologies the combination of natural and artificial lighting could lead to improvements in energy savings and comfort of living beings. Thus it is imperative to revisit or even improve daylighting research so that building networks of the future with their sensor, energy (e.g. HVAC) and lighting requirements can benefit from the emerging capabilities. This paper will briefly review existing daylighting concepts and technology and discuss new ideas. An example of a tunable multi-color SSL system will be shown.
Shumack, Stephen; Murrell, Dedee F; Rubel, Diana M; Fernández‐Peñas, Pablo; Salmon, Robert; Hewitt, Daniel; Foley, Peter; Spelman, Lynda
2015-01-01
Abstract Australia has the highest prevalence of actinic keratoses (AK) worldwide. Because of the risk of transformation of AK to invasive squamous cell carcinomas, consensus guidelines recommend that AK are removed using appropriate therapies to prevent progression to invasive disease. Daylight photodynamic therapy (PDT) is emerging as an efficacious treatment for AK, particularly for patients who require treatment of large areas of chronic actinic damage that can be exposed easily to daylight. Daylight PDT with methyl aminolevulinate (MAL) cream is a simple treatment for AK, almost painless, well tolerated and convenient, requiring minimal time in the clinic. Randomised controlled studies from northern Europe and Australia support the use of daylight PDT as an effective therapy for grade I and II AK on the face and scalp. There is sufficient daylight to conduct daylight PDT in Australia at any time of the year and during most weather conditions. Hence, daylight PDT with MAL can be included as an effective and well‐tolerated new treatment option for the treatment of AK in Australia. These consensus recommendations provide guidelines for Australian clinicians on the use of daylight PDT in the treatment of diagnosed AK. PMID:26033230
Katz, Erin M; Scott, Ruth M; Thomson, Christopher B; Mesa, Eileen; Evans, Richard; Conzemius, Michael G
2017-11-01
Objective To determine if environmental variables affect the average daily activity counts (AC) of dogs with osteoarthritis (OA) and/or owners' perception of their dog's clinical signs or quality of life. Methods The AC and Canine Brief Pain Inventory (CBPI) owner questionnaires of 62 dogs with OA were compared with daily environmental variables including the following: average temperature (°C), high temperature (°C), low temperature (°C), relative humidity (%), total precipitation (mm), average barometric pressure (hPa) and total daylight hours. Results Daily AC significantly correlated with average temperature and total daylight hours, but average temperature and total daylight hours accounted for less than 1% of variation in AC. No other significant relationships were found between daily AC and daily high temperature, low temperature, relative humidity, total precipitation or average barometric pressure. No statistical relationship was found between daily AC and the CBPI, nor between environmental variables and the CBPI. Canine Brief Pain Inventory scores for pain severity and pain interference decreased significantly over the test period. Clinical Significance The relationship between daily AC and average temperature and total daylight hours was significant, but unlikely to be clinically significant. Thus, environmental variables do not appear to have a clinically relevant bias on AC or owner CBPI questionnaires. The decrease over time in CBPI pain severity and pain interference values suggests owners completing the CBPI in this study were influenced by a caregiver placebo effect. Schattauer GmbH Stuttgart.
Measured daylighting potential of a static optical louver system under real sun and sky conditions
Konis, Kyle; Lee, Eleanor S.
2015-05-04
Side-by-side comparisons were made over solstice-to-solstice changes in sun and sky conditions between an optical louver system (OLS) and a conventional Venetian blind set at a horizontal slat angle and located inboard of a south-facing, small-area, clerestory window in a full-scale office testbed. Daylight autonomy (DA), window luminance, and ceiling luminance uniformity were used to assess performance. The performance of both systems was found to have significant seasonal variation, where performance under clear sky conditions improved as maximum solar altitude angles transitioned from solstice to equinox. Although the OLS produced fewer hours per day of DA on average than themore » Venetian blind, the OLS never exceeded the designated 2000 cd/m2 threshold for window glare. In contrast, the Venetian blind was found to exceed the visual discomfort threshold over a large fraction of the day during equinox conditions. Notably, these peak periods of visual discomfort occurred during the best periods of daylighting performance. Luminance uniformity was analyzed using calibrated high dynamic range luminance images. Under clear sky conditions, the OLS was found to increase the luminance of the ceiling as well as produce a more uniform distribution. Furthermore, compared to conventional venetian blinds, the static optical sunlight redirecting system studied has the potential to significantly reduce the annual electrical lighting energy demand of a daylit space and improve the quality from the perspective of building occupants by consistently transmitting useful daylight while eliminating window glare.« less
Daylighting in Schools: Improving Student Performance and Health at a Price Schools Can Afford.
ERIC Educational Resources Information Center
Plympton, Patricia; Conway, Susan; Epstein, Kyra
This document discusses evidence regarding daylighting and student performance and development, and presents four case studies of schools that have cost effectively implemented daylighting into their buildings. Case studies reveal that design and construction strategies that incorporate daylighting do not significantly increase costs over…
ERIC Educational Resources Information Center
Kennedy, Mike
2010-01-01
When the subject of buildings and daylighting arises, most people's thoughts will turn first to windows. To the uninitiated, it seems a simple formula: more windows, more daylight; fewer windows, less daylight. But designers know that effective use of daylighting in a building design involves more than just letting in light to otherwise darkened…
Diurnal trends in methylmercury concentration in a wetland adjacent to Great Salt Lake, Utah, USA
Naftz, D.L.; Cederberg, J.R.; Krabbenhoft, D.P.; Beisner, K.R.; Whitehead, J.; Gardberg, J.
2011-01-01
A 24-h field experiment was conducted during July 2008 at a wetland on the eastern shore of Great Salt Lake (GSL) to assess the diurnal cycling of methylmercury (MeHg). Dissolved (<0.45??m) MeHg showed a strong diurnal variation with consistently decreasing concentrations during daylight periods and increasing concentrations during non-daylight periods. The proportion of MeHg relative to total Hg in the water column consistently decreased with increasing sunlight duration, indicative of photodegradation. During the field experiment, measured MeHg photodegradation rates ranged from 0.02 to 0.06ngL-1h-1. Convective overturn of the water column driven by nighttime cooling of the water surface was hypothesized as the likely mechanism to replace the MeHg in the water column lost via photodegradation processes. A hydrodynamic model of the wetland successfully simulated convective overturn of the water column during the field experiment. Study results indicate that daytime monitoring of selected wetlands surrounding GSL may significantly underestimate the MeHg content in the water column. Wetland managers should consider practices that maximize the photodegradation of MeHg during daylight periods. ?? 2011.
EVALUATION OF A PROCEDURE FOR USING DAYLIGHT PROJECTION OF FILM LOOPS IN TEACHING SKILLS.
ERIC Educational Resources Information Center
HARBY, S.F.
EQUIPMENT USING A TRANSLUCENT SCREEN AND REAR PROJECTION HAS MADE IT POSSIBLE TO PROJECT MOTION PICTURES IN DAYLIGHT (DAYLIGHT PROJECTION). FILMS CAN BE SHOWN REPEATEDLY WHEN FORMED INTO A FILM LOOP (CONTINUOUS LOOP PROJECTION). DAYLIGHT PROJECTION AND CONTINUOUS LOOP PROJECTION WERE USED TO INVESTIGATE THE FOLLOWING QUESTIONS--(1) ARE FILM LOOP…
Predicting energy savings attributed to daylighting
NASA Astrophysics Data System (ADS)
Robbins, C. L.
1982-08-01
A method is described for estimating a building's energy savings attributed to daylighting by predicting the percentage of the year that the electric lighting system is not in use. This depends on the particular control strategy chosen, a standard work year, and the amount of light (as a daylight factor) reaching on daylight and sunlight availability for selected cities in the United States.
Daylighting in the workplace: Two new buildings offer a guiding light
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jackaway, A.; Littler, J.
1996-10-01
As environmental pressures intensify and energy efficiency remains paramount, there has been renewed interest in daylighting the workplace. Interestingly, daylighting`s resurgence is being furthered by mounting evidence of occupant dissatisfaction with predominantly electrically-lit offices, and two recent reports support growing concern that the lack of daylighting in these interiors has led not only to unhappy workers, but to potentially significant reductions in workplace productivity. Clearly pressure is mounting on designers to produce buildings responding to these concerns, and as the role of precedents in the evolution of design practice is unquestioned, demand has been increasing for publication of office-based daylightingmore » case studies. In an attempt to address this need, this paper examines two recently completed British buildings in which daylight has explicitly informed the architecture, and although data concerning the resulting energy savings is not yet available, these projects currently offer the design community two excellent examples of workplace daylighting where compelling visual environments are generating noteworthy occupant satisfaction.« less
Could Daylight Glare Be Defined Mathematically?Results of Testing the DGIN Method in Japan
NASA Astrophysics Data System (ADS)
Nazzal, Ali; Oki, Masato
Discomfort glare from daylight is a common problem without valid prediction methods so far. A new mathematical DGIN (New Daylight Glare Index) method tries to respond the challenge. This paper reports on experiments carried out in daylit office environment in Japan to test applicability of the method. Slight positive correlation was found between the DGIN and the subjective evaluation. Additionally, a high Ladaptation value together with the small ratio of Lwindow to Ladaptation was obviously experienced sufficient to neutralize the effect of glare discomfort. However, subjective assessments are poor glare indicators and not reliable in testing glare prediction methods. DGIN is a good indicator of daylight glare, and when the DGIN value is analyzed together with the measured illuminance ratios, discomfort glare from daylight can be analyzed in a quantitative manner. The DGIN method could serve architects and lighting designers in testing daylighting systems, and also guide the action of daylight responsive lighting controls.
Wagner, David T; Barnes, Christopher M; Lim, Vivien K G; Ferris, D Lance
2012-09-01
The Internet is a powerful tool that has changed the way people work. However, the ubiquity of the Internet has led to a new workplace threat to productivity-cyberloafing. Building on the ego depletion model of self-regulation, we examine how lost and low-quality sleep influence employee cyberloafing behaviors and how individual differences in conscientiousness moderate these effects. We also demonstrate that the shift to Daylight Saving Time (DST) results in a dramatic increase in cyberloafing behavior at the national level. We first tested the DST-cyberloafing relation through a national quasi-experiment, then directly tested the relation between sleep and cyberloafing in a closely controlled laboratory setting. We discuss the implications of our findings for theory, practice, and future research.
Designing a practical system for spectral imaging of skylight.
López-Alvarez, Miguel A; Hernández-Andrés, Javier; Romero, Javier; Lee, Raymond L
2005-09-20
In earlier work [J. Opt. Soc. Am. A 21, 13-23 (2004)], we showed that a combination of linear models and optimum Gaussian sensors obtained by an exhaustive search can recover daylight spectra reliably from broadband sensor data. Thus our algorithm and sensors could be used to design an accurate, relatively inexpensive system for spectral imaging of daylight. Here we improve our simulation of the multispectral system by (1) considering the different kinds of noise inherent in electronic devices such as change-coupled devices (CCDs) or complementary metal-oxide semiconductors (CMOS) and (2) extending our research to a different kind of natural illumination, skylight. Because exhaustive searches are expensive computationally, here we switch to a simulated annealing algorithm to define the optimum sensors for recovering skylight spectra. The annealing algorithm requires us to minimize a single cost function, and so we develop one that calculates both the spectral and colorimetric similarity of any pair of skylight spectra. We show that the simulated annealing algorithm yields results similar to the exhaustive search but with much less computational effort. Our technique lets us study the properties of optimum sensors in the presence of noise, one side effect of which is that adding more sensors may not improve the spectral recovery.
Angular selective window systems: Assessment of technical potential for energy savings
Fernandes, Luis L.; Lee, Eleanor S.; McNeil, Andrew; ...
2014-10-16
Static angular selective shading systems block direct sunlight and admit daylight within a specific range of incident solar angles. The objective of this study is to quantify their potential to reduce energy use and peak demand in commercial buildings using state-of-the art whole-building computer simulation software that allows accurate modeling of the behavior of optically-complex fenestration systems such as angular selective systems. Three commercial systems were evaluated: a micro-perforated screen, a tubular shading structure, and an expanded metal mesh. This evaluation was performed through computer simulation for multiple climates (Chicago, Illinois and Houston, Texas), window-to-wall ratios (0.15-0.60), building codes (ASHRAEmore » 90.1-2004 and 2010) and lighting control configurations (with and without). The modeling of the optical complexity of the systems took advantage of the development of state-of-the-art versions of the EnergyPlus, Radiance and Window simulation tools. Results show significant reductions in perimeter zone energy use; the best system reached 28% and 47% savings, respectively without and with daylighting controls (ASHRAE 90.1-2004, south facade, Chicago,WWR=0.45). As a result, angular selectivity and thermal conductance of the angle-selective layer, as well as spectral selectivity of low-emissivity coatings, were identified as factors with significant impact on performance.« less
Daylight characterization through vision-based sensing of lighting conditions in buildings
NASA Astrophysics Data System (ADS)
di Dio, Joseph, III
A new method for describing daylight under unknown weather conditions, as captured in images of a room, is proposed. This method considers pixel brightness information to be a linear combination of diffuse and directional light components, as received by a web cam from the walls and ceiling of an occupied office. The nature of these components in each image is determined by building orientation, room geometry, neighboring structures and the position of the sun. Considering daylight in this manner also allows for an estimation of the sky conditions at a given instant to be made, and presents a means to uncover seasonal trends in the behavior of light simply by monitoring the brightness variations of points on the walls and ceiling. Significantly, this daylight characterization method also allows for an estimation of the illumination level on a target surface to be made from image data. Currently, illumination at a target surface is estimated through the use of a ceiling-mounted photosensor, as part of a lighting control system, in the hopes of achieving a suitable balance between daylight and electrical lighting in a space. Improving the ability of a sensor to estimate the illumination is of great importance to those who wish to minimize unnecessary energy consumption, as a significant percentage of all U.S. electricity is currently consumed by light fixtures. A photosensor detects light that falls on its location, which does not necessarily correspond in a fixed manner to the light level on the target areas that the photosensor is meant to monitor. Additionally, a photosensor cannot discern variations in light distribution across a room, which often occur with daylight. By considering pixel brightness information to be a linear combination of diffuse and directional light components at selected pixels in an image, information about the light reaching these pixels can be extracted from observed patterns of brightness, under different light conditions. In this manner, each pixel provides information about the light field at its corresponding point in the room, and thus each pixel can be considered to behave as if it were a remote photosensor. By using multiple pixel readings in lieu of a single photosensor reading of a given light condition, an improved assessment of the illumination level on a target surface can been achieved. It is shown that on average, the camera-based method was approximately 25% more accurate in estimating illuminance in the test room than was a simulated ceiling-mounted photosensor. It is hoped that the methodology detailed here will aid in the eventual development of a camera-based daylight characterization sensor for use in lighting control systems, so that the potential for enhanced energy savings can be realized.
Lerche, Catharina M; Heerfordt, Ida M; Heydenreich, Jakob; Wulf, Hans Christian
2016-02-29
Daylight-mediated photodynamic therapy (daylight PDT) is a simple and pain free treatment of actinic keratoses. Weather conditions may not always allow daylight PDT outdoors. We compared the spectrum of five different lamp candidates for indoor "daylight PDT" and investigated their ability to photobleach protoporphyrin IX (PpIX). Furthermore, we measured the amount of PpIX activating daylight available in a glass greenhouse, which can be an alternative when it is uncomfortable for patients to be outdoors. The lamps investigated were: halogen lamps (overhead and slide projector), white light-emitting diode (LED) lamp, red LED panel and lamps used for conventional PDT. Four of the five light sources were able to photobleach PpIX completely. For halogen light and the red LED lamp, 5000 lux could photobleach PpIX whereas 12,000 lux were needed for the white LED lamp. Furthermore, the greenhouse was suitable for daylight PDT since the effect of solar light is lowered only by 25%. In conclusion, we found four of the five light sources and the greenhouse usable for indoor daylight PDT. The greenhouse is beneficial when the weather outside is rainy or windy. Only insignificant ultraviolet B radiation (UVB) radiation passes through the greenhouse glass, so sun protection is not needed.
Lerche, Catharina M.; Heerfordt, Ida M.; Heydenreich, Jakob; Wulf, Hans Christian
2016-01-01
Daylight-mediated photodynamic therapy (daylight PDT) is a simple and pain free treatment of actinic keratoses. Weather conditions may not always allow daylight PDT outdoors. We compared the spectrum of five different lamp candidates for indoor “daylight PDT” and investigated their ability to photobleach protoporphyrin IX (PpIX). Furthermore, we measured the amount of PpIX activating daylight available in a glass greenhouse, which can be an alternative when it is uncomfortable for patients to be outdoors. The lamps investigated were: halogen lamps (overhead and slide projector), white light-emitting diode (LED) lamp, red LED panel and lamps used for conventional PDT. Four of the five light sources were able to photobleach PpIX completely. For halogen light and the red LED lamp, 5000 lux could photobleach PpIX whereas 12,000 lux were needed for the white LED lamp. Furthermore, the greenhouse was suitable for daylight PDT since the effect of solar light is lowered only by 25%. In conclusion, we found four of the five light sources and the greenhouse usable for indoor daylight PDT. The greenhouse is beneficial when the weather outside is rainy or windy. Only insignificant ultraviolet B radiation (UVB) radiation passes through the greenhouse glass, so sun protection is not needed. PMID:26938525
76 FR 21318 - Notice of Funds Availability; Inviting Applications for the Quality Samples Program
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-15
... effect of this notice is to solicit applications from eligible applicants and to award funds in October... considered for funding, applications must be received by 5 p.m. Eastern Daylight Time, May 16, 2011. Any... INFORMATION CONTACT: Entities wishing to apply for funding assistance should contact the Program Operations...
Daylighting Makes a Difference.
ERIC Educational Resources Information Center
Heschong, Lisa; Knecht, Carey
2002-01-01
Examined the role of daylight in student achievement in three schools and found a uniformly positive and statistically significant correlation between the presence of more daylight and better student test scores. Offers guidelines on designing daylit classrooms. (EV)
Lighting system combining daylight concentrators and an artificial source
Bornstein, Jonathan G.; Friedman, Peter S.
1985-01-01
A combined lighting system for a building interior includes a stack of luminescent solar concentrators (LSC), an optical conduit made of preferably optical fibers for transmitting daylight from the LSC stack, a collimating lens set at an angle, a fixture for receiving the daylight at one end and for distributing the daylight as illumination inside the building, an artificial light source at the other end of the fixture for directing artifical light into the fixture for distribution as illumination inside the building, an automatic dimmer/brightener for the artificial light source, and a daylight sensor positioned near to the LSC stack for controlling the automatic dimmer/brightener in response to the daylight sensed. The system also has a reflector positioned behind the artificial light source and a fan for exhausting heated air out of the fixture during summer and for forcing heated air into the fixture for passage into the building interior during winter.
Indoor environmental quality (IEQ) of school classrooms: Case study in Malaysia
NASA Astrophysics Data System (ADS)
Samad, Muna Hanim Abdul; Aziz, Zalena Abdul; Isa, Mohd Hafizal Mohd
2017-10-01
Thermal Comfort is one of the key criteria for occupants' comfort and productivity in a building. In schools, it is vital for a conduciveness for teaching and learning environment. Thermal comfort is dependent on air temperature, humidity, radiation, internal lighting, air movement, activities, clothing and climatic change and is part of the Indoor Environmental Quality (IEQ) components which have has significant effects on occupants. The main concern over energy and running cost has meant that most public schools in Malaysia are designed for natural ventilation and not air-conditioning. The building envelope plays a significant role in reducing the radiant heat and keeps the interior cooler than the outdoor temperature for acceptable thermal comfort level. The requirement of Industrial Building System (IBS) as the envelope system for school building in Malaysia could affect the role of envelope as a climate moderator. This paper is based on a research conducted on two schools in Malaysia of varied construction materials as the building envelopes to ascertain the thermal comfort level of the classrooms. Elements of IEQ such as air temperature, air movement, daylighting and noise level were taken of various classrooms to fulfill the required objectives of determining the level of quality. The data collected and analysed from the study shows that in terms of air temperature which range from 28°C to 34.5°C, the schools do not achieve the recommended comfort level for tropical climate. As for daylighting element, results also show that some classrooms suffered with too much glare whilst others had insufficient daylighting. The findings also show the unsatisfactory level of air movement in the classrooms as well as an unacceptable noise level exceeding the allowable threshold. This research also concluded that the use of materials and orientation in the school design are the major determinant factors towards good IEQ levels in school buildings.
Analysis on energy use in reuse cement silo for campus building
NASA Astrophysics Data System (ADS)
Fidiya Nugrahani, Elita; Winda Murti, Izzati; Arifianti, Qurrotin M. O.
2018-03-01
Semen Gresik, the first cement factory in Indonesia owned by the government was operated since 1957 and stopped the operation around 1997. The owner, PT. Semen Indonesia (Persero) intended to reuse cement factory for the campus building, Universitas Internasional Semen Indonesia (UISI). This research proposed to analyze the future Energy Use Intensity (EUI) and recommendation energy efficiency in renovating silo through simulation. The result of future EUI in existing building was 234 kWh/m2.year. The scenarios created to reduce energy use in six sectors: window shades, window material, infiltration, daylighting, plug load, air-conditioning and operation schedule. The lowest EUI estimated at 98.27 by use 2/3 window shades, triple low emission window glass, lighting efficiency at 3.23 W/m2, maximize daylighting and occupancy control, minimize infiltration to 0.17 ACH, and 12/5 for operation schedule.
NASA Astrophysics Data System (ADS)
Sokol, Natalia; Martyniuk-Peczek, Justyna
2017-10-01
This paper reports on the partial results of the research aiming to illustrate how an integration of daylight design into an architectural planning process can help designers to create the residential buildings in respect to the environmental issues, solar and illuminance gains, as well as, the residents’ needs and comfort. It describes how changing daylight recommendations affected the design of the block of flats regarding their orientation, the spacing, the forms, and the size of the windows in the four urban residential areas. The results of this study help to determine more precise characterization of daylight indicators useful in architectural planning.
Daylighting simulation: methods, algorithms, and resources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carroll, William L.
This document presents work conducted as part of Subtask C, ''Daylighting Design Tools'', Subgroup C2, ''New Daylight Algorithms'', of the IEA SHC Task 21 and the ECBCS Program Annex 29 ''Daylight in Buildings''. The search for and collection of daylighting analysis methods and algorithms led to two important observations. First, there is a wide range of needs for different types of methods to produce a complete analysis tool. These include: Geometry; Light modeling; Characterization of the natural illumination resource; Materials and components properties, representations; and Usability issues (interfaces, interoperability, representation of analysis results, etc). Second, very advantageously, there have beenmore » rapid advances in many basic methods in these areas, due to other forces. They are in part driven by: The commercial computer graphics community (commerce, entertainment); The lighting industry; Architectural rendering and visualization for projects; and Academia: Course materials, research. This has led to a very rich set of information resources that have direct applicability to the small daylighting analysis community. Furthermore, much of this information is in fact available online. Because much of the information about methods and algorithms is now online, an innovative reporting strategy was used: the core formats are electronic, and used to produce a printed form only secondarily. The electronic forms include both online WWW pages and a downloadable .PDF file with the same appearance and content. Both electronic forms include live primary and indirect links to actual information sources on the WWW. In most cases, little additional commentary is provided regarding the information links or citations that are provided. This in turn allows the report to be very concise. The links are expected speak for themselves. The report consists of only about 10+ pages, with about 100+ primary links, but with potentially thousands of indirect links. For purposes of the printed version, a list of the links is explicitly provided. This document exists in HTML form at the URL address: http://eande.lbl.gov/Task21/dlalgorithms.html. An equivalent downloadable PDF version, also with live links, at the URL address: http://eande.lbl.gov/Task21/dlalgorithms.pdf. A printed report can be derived directly from either of the electronic versions by simply printing either of them. In addition to the live links in the electronic forms, all report forms, electronic and paper, also have explicitly listed link addresses so that they can be followed up or referenced manually.« less
DOT National Transportation Integrated Search
1975-06-01
The analyses of the effects of Year-Round Daylight Saving Time were not conslusive because they could not be reliablyseparated from other changes occuring simultaneously including fuel availability constraints, speed limit reductions, Sunday gasoline...
Daylight strategies for architectural studio facilities: the literature review
NASA Astrophysics Data System (ADS)
Othman, Muhammad Anas Bin; Azfahani Ahmad, Nur; Ajis, Azizah Md
2017-05-01
The implementation of daylighting strategies in buildings is a common aspect in architecture. However, due to the availability of inexpensive electricity, natural lighting strategies became insignificant, and been overlooked by designers. With the current concern over rapid increment on electricity cost, many designers now try to revitalized daylighting strategies in buildings. This includes educational buildings. In Malaysian cases, it is a norm that universities; especially during lecture and studio sessions, used artificial lighting throughout the day. Definitely, this is not parallel with the “green” aim made by the Government in the Malaysian Plan. Therefore, this paper aims to explore the impact of daylight strategies for educational studios in universities, by maximising the penetration of natural daylight into the space towards creating a more green-conducive studio. The paper review literature about the types, criteria and benefits of daylight strategies. This paper also presented a pilot study that has been performed in one university in Perak, Malaysia, by selecting architectural studios as the main subject.
Røislien, Jo; Søvik, Signe; Eken, Torsten
2018-01-01
Trauma is a leading global cause of death, and predicting the burden of trauma admissions is vital for good planning of trauma care. Seasonality in trauma admissions has been found in several studies. Seasonal fluctuations in daylight hours, temperature and weather affect social and cultural practices but also individual neuroendocrine rhythms that may ultimately modify behaviour and potentially predispose to trauma. The aim of the present study was to explore to what extent the observed seasonality in daily trauma admissions could be explained by changes in daylight and weather variables throughout the year. Retrospective registry study on trauma admissions in the 10-year period 2001-2010 at Oslo University Hospital, Ullevål, Norway, where the amount of daylight varies from less than 6 hours to almost 19 hours per day throughout the year. Daily number of admissions was analysed by fitting non-linear Poisson time series regression models, simultaneously adjusting for several layers of temporal patterns, including a non-linear long-term trend and both seasonal and weekly cyclic effects. Five daylight and weather variables were explored, including hours of daylight and amount of precipitation. Models were compared using Akaike's Information Criterion (AIC). A regression model including daylight and weather variables significantly outperformed a traditional seasonality model in terms of AIC. A cyclic week effect was significant in all models. Daylight and weather variables are better predictors of seasonality in daily trauma admissions than mere information on day-of-year.
Project Lateday : The Level of Accidents Under the Effect of Daylight Saving All Year
DOT National Transportation Integrated Search
1975-10-01
Year-round daylight saving time (YRDST) has recently been observed in the United States. The observance of double daylight saving time (DDST) is under some consideration. One of the principal expected effects of the adoption of these time systems is ...
Impact of Extended Daylight Saving Time on National Energy Consumption Report to Congress
DOE Office of Scientific and Technical Information (OSTI.GOV)
Belzer, D. B.; Hadley, S. W.; Chin, S-M.
2008-10-01
The Energy Policy Act of 2005 (Pub. L. No. 109-58; EPAct 2005) amended the Uniform Time Act of 1966 (Pub. L. No. 89-387) to increase the portion of the year that is subject to Daylight Saving Time. (15 U.S.C. 260a note) EPAct 2005 extended the duration of Daylight Saving Time in the spring by changing its start date from the first Sunday in April to the second Sunday in March, and in the fall by changing its end date from the last Sunday in October to the first Sunday in November. (15 U.S.C. 260a note) EPAct 2005 also called formore » the Department of Energy to evaluate the impact of Extended Daylight Saving Time on energy consumption in the United States and to submit a report to Congress. (15 U.S.C. 260a note) This report presents the results of impacts of Extended Daylight Saving Time on the national energy consumption in the United States. The key findings are: (1) The total electricity savings of Extended Daylight Saving Time were about 1.3 Tera Watt-hour (TWh). This corresponds to 0.5 percent per each day of Extended Daylight Saving Time, or 0.03 percent of electricity consumption over the year. In reference, the total 2007 electricity consumption in the United States was 3,900 TWh. (2) In terms of national primary energy consumption, the electricity savings translate to a reduction of 17 Trillion Btu (TBtu) over the spring and fall Extended Daylight Saving Time periods, or roughly 0.02 percent of total U.S. energy consumption during 2007 of 101,000 TBtu. (3) During Extended Daylight Saving Time, electricity savings generally occurred over a three- to five-hour period in the evening with small increases in usage during the early-morning hours. On a daily percentage basis, electricity savings were slightly greater during the March (spring) extension of Extended Daylight Saving Time than the November (fall) extension. On a regional basis, some southern portions of the United States exhibited slightly smaller impacts of Extended Daylight Saving Time on energy savings compared to the northern regions, a result possibly due to a small, offsetting increase in household air conditioning usage. (4) Changes in national traffic volume and motor gasoline consumption for passenger vehicles in 2007 were determined to be statistically insignificant and therefore, could not be attributed to Extended Daylight Saving Time.« less
Daylighting Concepts for University Libraries and Their Influences on Users' Satisfaction
ERIC Educational Resources Information Center
Kilic, Didem Kan; Hasirci, Deniz
2011-01-01
Daylighting, a controlled architectural tool that influences users' perception and behavior, in university libraries and their influences on users' preference and satisfaction was examined in this study. The effects of daylighting in coordination with visual comfort, on university library users were measured in relation to four environmental…
Effects of daylight savings time changes on stock market volatility.
Berument, M Hakan; Dogan, Nukhet; Onar, Bahar
2010-04-01
The presence of daylight savings time effects on stock returns and on stock volatility was investigated using an EGARCH specification to model the conditional variance. The evidence gathered from the major United States stock markets for the period between 1967 and 2007 did not support the existence of the daylight savings time effect on stock returns or on volatility. Returns on the first business day following daylight savings time changes were not lower nor was the volatility higher, as would be expected if there were an effect.
NASA Astrophysics Data System (ADS)
Zastrow, Armin; Wittwer, Volker
1986-09-01
The interest in efficient daylighting systems has grown recently, due to their potential for saving a considerable amount of electrical energy used for lighting purposes. In this paper we discuss the properties of daylighting systems based on either fluorescent planar concentrators and transparent light guiding plates or light pipes coated with highly reflective silver coated plastic films. Finally we give first results from a demonstration project, daylighting systems in the students' living quarters in Stuttgart-Hohenheim, which is supported by the Commission of the European Communities.
Heliostat design for the daylighting system.
Chang, Chih-Hung; Hsiso, Horng-Ching; Chang, Cheng-Ming; Wang, Chen-You; Lin, Tzung-Han; Chen, Yi-Yung; Lai, Yi-Lung; Yen, Cho-Jung; Chen, Kuan-Yu; Whang, Allen Jong-Woei
2014-10-10
The daylighting system is designed to guide sunlight into buildings for illumination. It has the best illumination performance when sunlight vertically impinges on the collector of the daylighting system, while it has low performance when sunlight impinges obliquely. To overcome the problem, this paper investigates the design of a heliostat that reflects sunlight vertically onto a daylighting system. This study proposes a 3×3 mirror matrix heliostat, which is different from the traditional heliostat with one single mirror. With the heliostat, the system efficiency increases as high as 3.32 times.
Adaptive chromogenic materials and devices
NASA Astrophysics Data System (ADS)
Sixou, Pierre; Guillard, H.; Labonne, L.; Gandolfo, V.
2003-03-01
Electrically controllable glasses can be used to control daylight and solar energy in buildings and in automotives in order to improve quality of life and to save energy spent on lighting, cooling and heating. The paper discusses the case of switchable glazings using liquid crystal/polymer micro-composites. A comparison with other technologies (like inorganic electrochromics, thermotropic gels and dispersed particles) is drawn.
Large aperture segmented optics for space-to-ground communications.
Lucy, R F
1968-08-01
A large aperture, moderate quality segmented optical array for use in noncoherent space-to-ground laser communications is determined as a function of resolution, diameter, focal length, and number of segments in the array. Secondary optics and construction tolerances are also discussed. Performance predictions show a typical receiver to be capable of megahertz communications at Mars distances during daylight operation.
Light Moves: Integrating Daylight into School Design from the Start
ERIC Educational Resources Information Center
Brossy de Dios, Eric; Rogic, Tinka; Vaughn, Wendell
2010-01-01
Numerous studies have demonstrated the benefits of daylight on the learning environment. Enhanced student performance and mood, increased teacher and student attendance, reduced energy costs, as well as a positive effect on the environment are some of the improvements seen in school buildings that use well-planned daylighting concepts. Looking at…
17 CFR 232.13 - Date of filing; adjustment of filing date.
Code of Federal Regulations, 2013 CFR
2013-04-01
... Standard Time or Eastern Daylight Saving Time, whichever is currently in effect, shall be deemed filed on.... Eastern Standard Time or Eastern Daylight Saving Time, whichever is currently in effect, shall be deemed... Daylight Savings Time, whichever is currently in effect, shall be deemed filed on the same business day. (4...
17 CFR 232.13 - Date of filing; adjustment of filing date.
Code of Federal Regulations, 2014 CFR
2014-04-01
... Standard Time or Eastern Daylight Saving Time, whichever is currently in effect, shall be deemed filed on.... Eastern Standard Time or Eastern Daylight Saving Time, whichever is currently in effect, shall be deemed... Daylight Savings Time, whichever is currently in effect, shall be deemed filed on the same business day. (4...
17 CFR 232.13 - Date of filing; adjustment of filing date.
Code of Federal Regulations, 2012 CFR
2012-04-01
... Standard Time or Eastern Daylight Saving Time, whichever is currently in effect, shall be deemed filed on.... Eastern Standard Time or Eastern Daylight Saving Time, whichever is currently in effect, shall be deemed... Daylight Savings Time, whichever is currently in effect, shall be deemed filed on the same business day. (4...
17 CFR 232.13 - Date of filing; adjustment of filing date.
Code of Federal Regulations, 2011 CFR
2011-04-01
... Standard Time or Eastern Daylight Saving Time, whichever is currently in effect, shall be deemed filed on.... Eastern Standard Time or Eastern Daylight Saving Time, whichever is currently in effect, shall be deemed... Daylight Savings Time, whichever is currently in effect, shall be deemed filed on the same business day. (4...
None
2018-02-14
Daylightingâthe use of windows or skylights for natural lighting and temperature regulationâis one building strategy that can save money for homeowners and businesses. Highly efficient, strategically placed windows maximize the use of natural daylight in a building, lowering the need for artificial lighting without causing heating or cooling problems.
Testing simulation and structural models with applications to energy demand
NASA Astrophysics Data System (ADS)
Wolff, Hendrik
2007-12-01
This dissertation deals with energy demand and consists of two parts. Part one proposes a unified econometric framework for modeling energy demand and examples illustrate the benefits of the technique by estimating the elasticity of substitution between energy and capital. Part two assesses the energy conservation policy of Daylight Saving Time and empirically tests the performance of electricity simulation. In particular, the chapter "Imposing Monotonicity and Curvature on Flexible Functional Forms" proposes an estimator for inference using structural models derived from economic theory. This is motivated by the fact that in many areas of economic analysis theory restricts the shape as well as other characteristics of functions used to represent economic constructs. Specific contributions are (a) to increase the computational speed and tractability of imposing regularity conditions, (b) to provide regularity preserving point estimates, (c) to avoid biases existent in previous applications, and (d) to illustrate the benefits of our approach via numerical simulation results. The chapter "Can We Close the Gap between the Empirical Model and Economic Theory" discusses the more fundamental question of whether the imposition of a particular theory to a dataset is justified. I propose a hypothesis test to examine whether the estimated empirical model is consistent with the assumed economic theory. Although the proposed methodology could be applied to a wide set of economic models, this is particularly relevant for estimating policy parameters that affect energy markets. This is demonstrated by estimating the Slutsky matrix and the elasticity of substitution between energy and capital, which are crucial parameters used in computable general equilibrium models analyzing energy demand and the impacts of environmental regulations. Using the Berndt and Wood dataset, I find that capital and energy are complements and that the data are significantly consistent with duality theory. Both results would not necessarily be achieved using standard econometric methods. The final chapter "Daylight Time and Energy" uses a quasi-experiment to evaluate a popular energy conservation policy: we challenge the conventional wisdom that extending Daylight Saving Time (DST) reduces energy demand. Using detailed panel data on half-hourly electricity consumption, prices, and weather conditions from four Australian states we employ a novel 'triple-difference' technique to test the electricity-saving hypothesis. We show that the extension failed to reduce electricity demand and instead increased electricity prices. We also apply the most sophisticated electricity simulation model available in the literature to the Australian data. We find that prior simulation models significantly overstate electricity savings. Our results suggest that extending DST will fail as an instrument to save energy resources.
Daylight and absenteeism--evidence from Norway.
Markussen, Simen; Røed, Knut
2015-01-01
Based on administrative register data from Norway, we examine the impact of hours of daylight on sick-leave absences among workers. Our preferred estimates imply that an additional hour of daylight increases the daily entry rate to absenteeism by 0.5 percent and the corresponding recovery rate by 0.8 percent, ceteris paribus. The overall relationship between absenteeism and daylight hours is negative. Absenteeism is also sensitive to weather conditions. Heavy snowfall raises the incidence of absence during the winter, while warm weather reduces the probability of returning to work during the summer. Copyright © 2014 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Zastrow, Armin; Wittwer, Volker
1987-02-01
Efficient daylighting systems have recently attracted increasing interest due to their potential for saving a condiderable amount of electrical energy used for lighting purposes. In this paper we discuss the properties of daylighting systems based on either fluorescent planar concentrators (FPC's) and transparent light guiding plates or light pipes coated with a highly reflective silver coated plastic film (3M Silverlux film). First results on daylighting systems in the students' living quarters in Stuttgart-Hohenheim will be presented. This is a demonstration project which is supported by the Commission of the European Communities.
17 CFR 240.0-2 - Business hours of the Commission.
Code of Federal Regulations, 2012 CFR
2012-04-01
... Eastern Daylight Saving Time, whichever currently is in effect in Washington, DC, provided that hours for... 8 a.m. to 10 p.m., Eastern Standard Time or Eastern Daylight Saving Time, whichever is currently in... Saturdays, Sundays and federal holidays, from 8 a.m. to 5:30 p.m., Eastern Standard Time or Eastern Daylight...
17 CFR 240.0-2 - Business hours of the Commission.
Code of Federal Regulations, 2011 CFR
2011-04-01
... Eastern Daylight Saving Time, whichever currently is in effect in Washington, DC, provided that hours for... 8 a.m. to 10 p.m., Eastern Standard Time or Eastern Daylight Saving Time, whichever is currently in... Saturdays, Sundays and federal holidays, from 8 a.m. to 5:30 p.m., Eastern Standard Time or Eastern Daylight...
Predicting energy savings attributed to daylighting
NASA Astrophysics Data System (ADS)
Robbins, C. L.
1983-11-01
A method for estimating a building's energy savings attributable to daylighting by predicting the percentage of the year that the electric lighting system is not in use is described. This method depends upon the particular control stragegy chosen, a standard work year, and the amount of light (as a daylight factor, DF) reaching any given station in the building.
Development of a Persistent Chemical Agent Simulator System (PCASS)
NASA Technical Reports Server (NTRS)
Mcginness, W. G.
1983-01-01
The development of a persistent chemical agent simulation system (PCASS) is described. This PCASS is to be used for the military training of troops to simulate actual chemical warfare. The purpose of this system is to facilitate in the determination of chemical contamination and effectiveness of decontamination for training purposes. The fluorescent tracer employed has no daylight activation, but yet is easily removed with a decontaminate solution or water and surfactants. Also employed is a time delayed color developing system. When an individual is subjected to the PCASS and does not decontaminate adequately, red blotches or red coloration will develop as a function of time and temperature. The intent of this is to simulate the delayed chemical reaction of mustard contaminates.
NASA Technical Reports Server (NTRS)
Griffin, Brand Norman
2010-01-01
With 1 rover, 2 astronauts and 3 days, the Apollo 17 Mission covered over 30 km, setup 10 scientific experiments and returned 110 kg of samples. This is a lot of science in a short time and the inspiration for a barebones, return-to-the-Moon strategy called Daylight Exploration. The Daylight Exploration approach poses an answer to the question, What could the Apollo crew have done with more time and today s robotics? In contrast to more ambitious and expensive strategies that create outposts then rely on pressurized rovers to drive to the science sites, Daylight Exploration is a low-overhead approach conceived to land near the scientific site, conduct Apollo-like exploration then leave before the sun goes down. A key motivation behind Daylight Exploration is cost reduction, but it does not come at the expense of scientific exploration. As a goal, Daylight Exploration provides access to the top 10 science sites by using the best capabilities of human and robotic exploration. Most science sites are within an equatorial band of 26 degrees latitude and on the Moon, at the equator, the day is 14 Earth days long; even more important, the lunar night is 14 days long. Human missions are constrained to 12 days because the energy storage systems required to operate during the lunar night adds mass, complexity and cost. In addition, short missions are beneficial because they require fewer consumables, do not require an airlock, reduce radiation exposure, minimize the dwell-time for the ascent and orbiting propulsion systems and allow a low-mass, campout accommodations. Key to Daylight Exploration is the use of piloted rovers used as tele-operated science platforms. Rovers are launched before or with the crew, and continue to operate between crew visits analyzing and collecting samples during the lunar daylight
Light field and water clarity simulation of natural environments in laboratory conditions
NASA Astrophysics Data System (ADS)
Pe'eri, Shachak; Shwaery, Glenn
2012-06-01
Simulation of natural oceanic conditions in a laboratory setting is a challenging task, especially when that environment can be miles away. We present an attempt to replicate the solar radiation expected at different latitudes with varying water clarity conditions up to 30 m in depth using a 2.5 m deep engineering tank at the University of New Hampshire. The goals of the study were: 1) to configure an underwater light source that produced an irradiance spectrum similar to natural daylight with the sun at zenith and at 60° under clear atmospheric conditions, and 2) to monitor water clarity as a function of depth. Irradiance was measured using a spectra-radiometer with a cosine receiver to analyze the output spectrum of submersed lamps as a function of distance. In addition, an underwater reflection method was developed to measure the diffuse attenuation coefficient in real time. Two water clarity types were characterized, clear waters representing deep, open-ocean conditions, and murky waters representing littoral environments. Results showed good correlation between the irradiance measured at 400 nm to 600 nm and the natural daylight spectrum at 3 m from the light source. This can be considered the water surface conditions reference. Using these methodologies in a controlled laboratory setting, we are able to replicate illumination and water conditions to study the physical, chemical and biological processes on natural and man-made objects and/or systems in simulated, varied geographic locations and environments.
ERIC Educational Resources Information Center
Hill, Alva L.; Lawrence, Jerry
In recent years one of the most prevalent requests directed to design architects by teachers and administrative personnel is to include in the architectural program for their new school provisions for admitting more daylight into their classrooms. This guide by the American Institute of Architects National Committee on Architecture for Education…
Hicks, G J; Davis, J W; Hicks, R A
1998-06-01
On the hypothesis that sleepiness and alcohol interact to increase the risk of alcohol-related traffic fatalities, the percentages of alcohol-related fatal traffic crashes were assessed for the entire state of New Mexico for the years 1989-1992, for each of the seven days that preceded the changes to and from Daylight Savings Time and for each of the 14 days which followed the changes to and from Daylight Savings Time. Consistent with our hypothesis the percentage of alcohol-related fatal crashes increased significantly during the first seven days after these changes in Daylight Savings Time.
Colour Model for Outdoor Machine Vision for Tropical Regions and its Comparison with the CIE Model
NASA Astrophysics Data System (ADS)
Sahragard, Nasrolah; Ramli, Abdul Rahman B.; Hamiruce Marhaban, Mohammad; Mansor, Shattri B.
2011-02-01
Accurate modeling of daylight and surface reflectance are very useful for most outdoor machine vision applications specifically those which are based on color recognition. Existing daylight CIE model has drawbacks that limit its ability to predict the color of incident light. These limitations include lack of considering ambient light, effects of light reflected off the ground, and context specific information. Previously developed color model is only tested for a few geographical places in North America and its accountability is under question for other places in the world. Besides, existing surface reflectance models are not easily applied to outdoor images. A reflectance model with combined diffuse and specular reflection in normalized HSV color space could be used to predict color. In this paper, a new daylight color model showing the color of daylight for a broad range of sky conditions is developed which will suit weather conditions of tropical places such as Malaysia. A comparison of this daylight color model and daylight CIE model will be discussed. The colors of matte and specular surfaces have been estimated by use of the developed color model and surface reflection function in this paper. The results are shown to be highly reliable.
Daylight saving time transitions and hospital treatments due to accidents or manic episodes
Lahti, Tuuli A; Haukka, Jari; Lönnqvist, Jouko; Partonen, Timo
2008-01-01
Background Daylight saving time affects millions of people annually but its impacts are still widely unknown. Sleep deprivation and the change of circadian rhythm can trigger mental illness and cause higher accident rates. Transitions into and out of daylight saving time changes the circadian rhythm and may cause sleep deprivation. Thus it seems plausible that the prevalence of accidents and/or manic episodes may be higher after transition into and out of daylight saving time. The aim of this study was to explore the effects of transitions into and out of daylight saving time on the incidence of accidents and manic episodes in the Finnish population during the years of 1987 to 2003. Methods The nationwide data were derived from the Finnish Hospital Discharge Register. From the register we obtained the information about the hospital-treated accidents and manic episodes during two weeks before and two weeks after the transitions in 1987–2003. Results The results were negative, as the transitions into or out of daylight saving time had no significant effect on the incidence of accidents or manic episodes. Conclusion One-hour transitions do not increase the incidence of manic episodes or accidents which require hospital treatment. PMID:18302734
The Role of Daylighting in Skilled Nursing Short-Term Rehabilitation Facilities.
Gharaveis, Arsalan; Shepley, Mardelle McCuskey; Gaines, Kristi
2016-01-01
The aim of this study is to investigate the best placement of windows in short-term rehabilitation facilities in terms of daylighting and outdoor views by exploring the impact of windows on resident perception of stress, mood, activities, and satisfaction. The physiological and psychological benefits of daylighting have made it an increasingly important topic in multidisciplinary research. Although multiple studies have been written about the impact of daylight on physiological responses, few investigations have been made into the nonvisual effects related to resident mood, satisfaction, and stress level. In addition, researchers typically propose recommendations for quantitative aspects of illuminance, rather than addressing the behavioural outcomes. A combination of qualitative and quantitative methodologies were used to address the research questions. Thirty-four participants, who were living temporarily in the inpatient rehabilitation units of two skilled nursing facilities, were subjects in semistructured interviews and a 7-question 5-scale survey. While residents expressed the need to have direct visual access to the outdoors, they indicated that daylight was of even higher benefit. Additionally, they noted that size and location of windows impacted their stress levels, moods, and activities. More than half of the facility residents reported changing their postures for either better outdoor views or less light disturbance while sleeping. The results of this study emphasize the importance of daylighting for residents in rehabilitation units. Architects should acknowledge the role of daylighting and window views in the design of rehabilitation facilities. © The Author(s) 2015.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thayer, B.M.
A daylight office building built for Lockheed Martin near San Francisco has saved half a million dollars on energy bills and several times more due to reduced absenteeism and improved employee productivity. The building design incorporates soft daylight throughout the interior of the building. This article discusses the following topics in relationship to the building design: design for the climate; deep daylighting; integrated electric lighting; mechanical system; energy performance; the productivity story.
Advanced Lighting Controls for Reducing Energy Use and Cost in DoD Installations
2013-03-01
of advanced lighting control strategies including occupancy sensing, light tuning, daylight harvesting and proper lighting design is an effective way...details of this project and the results obtained. 15. SUBJECT TERMS Integrated lighting controls, occupancy sensing, daylight harvesting , personalized...provide energy savings through occupancy sensing, dimming and daylight harvesting . II. Dynalite is a distributed control-based, wired networked building
Empirical assessment of a prismatic daylight-redirecting window film in a full-scale office testbed
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thanachareonkit, Anothai; Lee, Eleanor S.; McNeil, Andrew
2013-08-31
Daylight redirecting systems with vertical windows have the potential to offset lighting energy use in deep perimeter zones. Microstructured prismatic window films can be manufactured using low-cost, roll-to-roll fabrication methods and adhered to the inside surface of existing windows as a retrofit measure or installed as a replacement insulating glass unit in the clerestory portion of the window wall. A clear film patterned with linear, 50-250 micrometer high, four-sided asymmetrical prisms was fabricated and installed in the south-facing, clerestory low-e, clear glazed windows of a full-scale testbed facility. Views through the film were distorted. The film was evaluated in amore » sunny climate over a two-year period to gauge daylighting and visual comfort performance. The daylighting aperture was small (window-towall ratio of 0.18) and the lower windows were blocked off to isolate the evaluation to the window film. Workplane illuminance measurements were made in the 4.6 m (15 ft) deep room furnished as a private office. Analysis of discomfort glare was conducted using high dynamic range imaging coupled with the evalglare software tool, which computes the daylight glare probability and other metrics used to evaluate visual discomfort. The window film was found to result in perceptible levels of discomfort glare on clear sunny days from the most conservative view point in the rear of the room looking toward the window. Daylight illuminance levels at the rear of the room were significantly increased above the reference window condition, which was defined as the same glazed clerestory window but with an interior Venetian blind (slat angle set to the cut-off angle), for the equinox to winter solstice period on clear sunny days. For partly cloudy and overcast sky conditions, daylight levels were improved slightly. To reduce glare, the daylighting film was coupled with a diffusing film in an insulating glazing unit. The diffusing film retained the directionality of the redirected light spreading it within a small range of outgoing angles. This solution was found to reduce glare to imperceptible levels while retaining for the most part the illuminance levels achieved solely by the daylighting film.« less
Robust colour constancy in red-green dichromats
Linhares, João M. M.; Moreira, Humberto; Lillo, Julio; Nascimento, Sérgio M. C.
2017-01-01
Colour discrimination has been widely studied in red-green (R-G) dichromats but the extent to which their colour constancy is affected remains unclear. This work estimated the extent of colour constancy for four normal trichromatic observers and seven R-G dichromats when viewing natural scenes under simulated daylight illuminants. Hyperspectral imaging data from natural scenes were used to generate the stimuli on a calibrated CRT display. In experiment 1, observers viewed a reference scene illuminated by daylight with a correlated colour temperature (CCT) of 6700K; observers then viewed sequentially two versions of the same scene, one illuminated by either a higher or lower CCT (condition 1, pure CCT change with constant luminance) or a higher or lower average luminance (condition 2, pure luminance change with a constant CCT). The observers’ task was to identify the version of the scene that looked different from the reference scene. Thresholds for detecting a pure CCT change or a pure luminance change were estimated, and it was found that those for R-G dichromats were marginally higher than for normal trichromats regarding CCT. In experiment 2, observers viewed sequentially a reference scene and a comparison scene with a CCT change or a luminance change above threshold for each observer. The observers’ task was to identify whether or not the change was an intensity change. No significant differences were found between the responses of normal trichromats and dichromats. These data suggest robust colour constancy mechanisms along daylight locus in R-G dichromacy. PMID:28662218
Robust colour constancy in red-green dichromats.
Álvaro, Leticia; Linhares, João M M; Moreira, Humberto; Lillo, Julio; Nascimento, Sérgio M C
2017-01-01
Colour discrimination has been widely studied in red-green (R-G) dichromats but the extent to which their colour constancy is affected remains unclear. This work estimated the extent of colour constancy for four normal trichromatic observers and seven R-G dichromats when viewing natural scenes under simulated daylight illuminants. Hyperspectral imaging data from natural scenes were used to generate the stimuli on a calibrated CRT display. In experiment 1, observers viewed a reference scene illuminated by daylight with a correlated colour temperature (CCT) of 6700K; observers then viewed sequentially two versions of the same scene, one illuminated by either a higher or lower CCT (condition 1, pure CCT change with constant luminance) or a higher or lower average luminance (condition 2, pure luminance change with a constant CCT). The observers' task was to identify the version of the scene that looked different from the reference scene. Thresholds for detecting a pure CCT change or a pure luminance change were estimated, and it was found that those for R-G dichromats were marginally higher than for normal trichromats regarding CCT. In experiment 2, observers viewed sequentially a reference scene and a comparison scene with a CCT change or a luminance change above threshold for each observer. The observers' task was to identify whether or not the change was an intensity change. No significant differences were found between the responses of normal trichromats and dichromats. These data suggest robust colour constancy mechanisms along daylight locus in R-G dichromacy.
Lee, Eleanor S.; Geisler-Moroder, David; Ward, Gregory
2017-12-23
Simulation tools that enable annual energy performance analysis of optically-complex fenestration systems have been widely adopted by the building industry for use in building design, code development, and the development of rating and certification programs for commercially-available shading and daylighting products. The tools rely on a three-phase matrix operation to compute solar heat gains, using as input low-resolution bidirectional scattering distribution function (BSDF) data (10–15° angular resolution; BSDF data define the angle-dependent behavior of light-scattering materials and systems). Measurement standards and product libraries for BSDF data are undergoing development to support solar heat gain calculations. Simulation of other metrics suchmore » as discomfort glare, annual solar exposure, and potentially thermal discomfort, however, require algorithms and BSDF input data that more accurately model the spatial distribution of transmitted and reflected irradiance or illuminance from the sun (0.5° resolution). This study describes such algorithms and input data, then validates the tools (i.e., an interpolation tool for measured BSDF data and the five-phase method) through comparisons with ray-tracing simulations and field monitored data from a full-scale testbed. Simulations of daylight-redirecting films, a micro-louvered screen, and venetian blinds using variable resolution, tensor tree BSDF input data derived from interpolated scanning goniophotometer measurements were shown to agree with field monitored data to within 20% for greater than 75% of the measurement period for illuminance-based performance parameters. The three-phase method delivered significantly less accurate results. We discuss the ramifications of these findings on industry and provide recommendations to increase end user awareness of the current limitations of existing software tools and BSDF product libraries.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Eleanor S.; Geisler-Moroder, David; Ward, Gregory
Simulation tools that enable annual energy performance analysis of optically-complex fenestration systems have been widely adopted by the building industry for use in building design, code development, and the development of rating and certification programs for commercially-available shading and daylighting products. The tools rely on a three-phase matrix operation to compute solar heat gains, using as input low-resolution bidirectional scattering distribution function (BSDF) data (10–15° angular resolution; BSDF data define the angle-dependent behavior of light-scattering materials and systems). Measurement standards and product libraries for BSDF data are undergoing development to support solar heat gain calculations. Simulation of other metrics suchmore » as discomfort glare, annual solar exposure, and potentially thermal discomfort, however, require algorithms and BSDF input data that more accurately model the spatial distribution of transmitted and reflected irradiance or illuminance from the sun (0.5° resolution). This study describes such algorithms and input data, then validates the tools (i.e., an interpolation tool for measured BSDF data and the five-phase method) through comparisons with ray-tracing simulations and field monitored data from a full-scale testbed. Simulations of daylight-redirecting films, a micro-louvered screen, and venetian blinds using variable resolution, tensor tree BSDF input data derived from interpolated scanning goniophotometer measurements were shown to agree with field monitored data to within 20% for greater than 75% of the measurement period for illuminance-based performance parameters. The three-phase method delivered significantly less accurate results. We discuss the ramifications of these findings on industry and provide recommendations to increase end user awareness of the current limitations of existing software tools and BSDF product libraries.« less
NASA Astrophysics Data System (ADS)
Linhart, Friedrich; Wittkopf, Stephen K.; Münch, Mirjam; Scartezzini, Jean-Louis
2009-08-01
Making daylight more available in buildings is highly desirable for reasons of energy efficiency, visual comfort, occupant well-being and health. The Anidolic Integrated Ceiling (AIC) is a highly efficient daylighting system, designed to gather and redirect daylight from the outside of a building into its interior with minimal losses. The reflective coating materials used within AICs have a major impact on the optical efficiency of such systems. The first part of our article presents a new computer model of an AIC consisting of more than 30 distinct components. We discuss on which of them the use of expensive, highly reflective coatings makes the most sense. We conclude that coating the component "Anidolic element 1" is always a good choice and that considerable financial savings can be obtained by following an appropriate optimization sequence.The second part of our article discusses chronobiological properties of Anidolic Daylighting Systems (ADS). We recorded daytime irradiance values for several weeks from March to May 2009 in an experimental office setup in our laboratory using a portable digital spectroradiometer. Our results showed to which extent different sky conditions influenced daylight exposure of office workers in an ADS-equipped office room. We conclude that for the tested ADS-equipped office room, daylight supply can be considered largely sufficient during long periods on most working days. However, complementary artificial lighting with blue-enriched polychromatic fluorescent tubes might be useful on days with predominantly overcast skies as well as before 09:00 and after 16:30 on all days.
Highlighting High Performance: Michael E. Capuano Early Childhood Center; Somerville, Massachusetts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
2006-03-01
This brochure describes the key high-performance building features of the Michael E. Capuano Early Childhood Center. The brochure was paid for by the Massachusetts Technology Collaborative as part of their Green Schools Initiative. High-performance features described are daylighting and energy-efficient lighting, indoor air quality, solar and wind energy, building envelope, heating and cooling systems, water conservation, and acoustics. Energy cost savings are also discussed.
On Target: Organizing and Executing the Strategic Air Campaign Against Iraq
2002-01-01
possession, use, sale, creation or display of any porno graphic photograph, videotape, movie, drawing, book, or magazine or similar represen- tations. This...forward-looking infrared (FLIR) sensor to create daylight-quality video images of terrain and utilized terrain-following radar to enable the aircraft to...The Black Hole Planners had pleaded with CENTAF Intel to provide them with photos of targets, provide additional personnel to analyze PGM video
PHYSICAL INFRASTRUCTURE: Crosscutting Issues Planning Conference Report
2001-10-01
critical for reducing water use. As soon as you shift to increasing block tariffs, this will result in changing cropping patterns that reduce...because, as we manage our load, we can also manage our costs. I wanted to give you an idea of the context of energy use in the federal...Energy Management Program, Department of EnergyNext, to enhance indoor environmental quality, think about things, such as whether you have daylighting
Laike, Thorbjörn; Morita, Takeshi
2018-01-01
The purpose of the study was to investigate seasonal variation in mood and behavior among a group of office workers in Sweden (56°N). Thirty subjects participated in this longitudinal study. The subjects kept a weekly log that included questionnaires for ratings of psychological wellbeing and daily sleep-activity diaries where they also noted time spent outdoors. The lighting conditions in the offices were subjectively evaluated during one day, five times over the year. There was a seasonal variation in positive affect and in sleep-activity behavior. Across the year, there was a large variation in the total time spent outdoors in daylight. The subjects reported seasonal variation concerning the pleasantness, variation and strength of the light in the offices and regarding the visibility in the rooms. Finally, the subjects spent most of their time indoors, relying on artificial lighting, which demonstrates the importance of the lighting quality in indoor environments.
Melbye, Sigurd; Hotvedt, Martin; Bolle, Stein Roald
2014-06-02
Videoconferencing on mobile phones may enhance communication, but knowledge on its quality in various situations is needed before it can be used in medical emergencies. Mobile phones automatically activate loudspeaker functionality during videoconferencing, making calls particularly vulnerable to background noise. The aim of this study was to investigate if videoconferencing can be used between lay bystanders and Emergency Medical Dispatch (EMD) operators for initial emergency calls during medical emergencies, under suboptimal sound and light conditions. Videoconferencing was tested between 90 volunteers and an emergency medical dispatcher in a standardized scenario of a medical emergency. Three different environments were used for the trials: indoors with moderate background noise, outdoors with daylight and much background noise, and outdoors during nighttime with little background noise. Thirty participants were recruited for each of the three locations. After informed consent, each participant was asked to use a video mobile phone to communicate with an EMD operator. During the video call the EMD operator gave instructions for tasks to be performed by the participant. The video quality from the caller to the EMD was evaluated by the EMD operator and rated on a five step scale ranging from "not able to see" to "good video quality". Sound quality between participants and EMD operators was assessed by a method developed for this trial. Kruskal - Wallis and Chi-square tests were used for statistical analysis. Video quality was significantly different between the groups (p <0.001), and the nighttime group had lower video quality. For most sessions in the nighttime group it was still possible to see actions done at the simulated emergency site. All participants were able to perform their tasks according to the instructions given by dispatchers, although with a need for more repetitions during sessions with much background noise. No calls were rated by dispatchers as incomprehensible due to low sound quality and only 3% of the calls were considered somewhat difficult or very difficult to understand. Videoconferencing on mobile phones can be used for the initial emergency call during medical emergencies also in suboptimal conditions.
Variation of outdoor illumination as a function of solar elevation and light pollution
NASA Astrophysics Data System (ADS)
Spitschan, Manuel; Aguirre, Geoffrey K.; Brainard, David H.; Sweeney, Alison M.
2016-06-01
The illumination of the environment undergoes both intensity and spectral changes during the 24 h cycle of a day. Daylight spectral power distributions are well described by low-dimensional models such as the CIE (Commission Internationale de l’Éclairage) daylight model, but the performance of this model in non-daylight regimes is not characterised. We measured downwelling spectral irradiance across multiple days in two locations in North America: One rural location (Cherry Springs State Park, PA) with minimal anthropogenic light sources, and one city location (Philadelphia, PA). We characterise the spectral, intensity and colour changes and extend the existing CIE model for daylight to capture twilight components and the spectrum of the night sky.
Variation of outdoor illumination as a function of solar elevation and light pollution
Spitschan, Manuel; Aguirre, Geoffrey K.; Brainard, David H.; Sweeney, Alison M.
2016-01-01
The illumination of the environment undergoes both intensity and spectral changes during the 24 h cycle of a day. Daylight spectral power distributions are well described by low-dimensional models such as the CIE (Commission Internationale de l’Éclairage) daylight model, but the performance of this model in non-daylight regimes is not characterised. We measured downwelling spectral irradiance across multiple days in two locations in North America: One rural location (Cherry Springs State Park, PA) with minimal anthropogenic light sources, and one city location (Philadelphia, PA). We characterise the spectral, intensity and colour changes and extend the existing CIE model for daylight to capture twilight components and the spectrum of the night sky. PMID:27272736
Daylighting in the Springfield (Ohio) Museum of Art
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moore, F.
This paper describes daylighting strategies used in the addition to the Springfield Museum of Art, Springfield, Ohio. The interior daylighting illuminances and luminances have been measured and these data are presented. The original museum was built in 1958. This original portion is approximately 18,000 ft{sup 2} (1,674 m{sup 2}) floor area and was remodeled as part of the 1995 addition to house and art school, cataloging, preparation, and administrative functions. The new addition is approximately 10,000 ft{sup 2} (930 m{sup 2}) and is primarily exhibit galleries with some additional administrative offices. Glaser Associated were the architects (Michael Moose, project architect)more » and the author was the daylighting consultant on the project.« less
Variation of outdoor illumination as a function of solar elevation and light pollution.
Spitschan, Manuel; Aguirre, Geoffrey K; Brainard, David H; Sweeney, Alison M
2016-06-07
The illumination of the environment undergoes both intensity and spectral changes during the 24 h cycle of a day. Daylight spectral power distributions are well described by low-dimensional models such as the CIE (Commission Internationale de l'Éclairage) daylight model, but the performance of this model in non-daylight regimes is not characterised. We measured downwelling spectral irradiance across multiple days in two locations in North America: One rural location (Cherry Springs State Park, PA) with minimal anthropogenic light sources, and one city location (Philadelphia, PA). We characterise the spectral, intensity and colour changes and extend the existing CIE model for daylight to capture twilight components and the spectrum of the night sky.
Gilaberte, Y; Aguilar, M; Almagro, M; Correia, O; Guillén, C; Harto, A; Pérez-García, B; Pérez-Pérez, L; Redondo, P; Sánchez-Carpintero, I; Serra-Guillén, C; Valladares, L M
2015-10-01
Daylight-mediated photodynamic therapy (PDT) is a new type of PDT that is as effective as conventional PDT in grade 1 and 2 actinic keratosis but with fewer adverse effects, resulting in greater efficiency. The climatic conditions in the Iberian Peninsula require an appropriately adapted consensus protocol. We describe a protocol for the treatment of grade 1 and 2 actinic keratosis with daylight-mediated PDT and methyl aminolevulinate (MAL) adapted to the epidemiological and clinical characteristics of Spanish and Portuguese patients and the climatic conditions of both countries. Twelve dermatologists from different parts of Spain and Portugal with experience in the treatment of actinic keratosis with PDT convened to draft a consensus statement for daylight-mediated PDT with MAL in these countries. Based on a literature review and their own clinical experience, the group developed a recommended protocol. According to the recommendations adopted, patients with multiple grade 1 and 2 lesions, particularly those at risk of developing cancer, are candidates for this type of therapy. Daylight-mediated PDT can be administered throughout the year, although it is not indicated at temperatures below 10°C or at excessively high temperatures. Likewise, therapy should not be administered when it is raining, snowing, or foggy. The procedure is simple, requiring application of a sunscreen with a protection factor of at least 30 based exclusively on organic filters, appropriate preparation of the lesions, application of MAL without occlusion, and activation in daylight for 2hours. This consensus statement represents a practical and detailed guideline to achieve maximum effectiveness of daylight-mediated PDT with MAL in Spain and Portugal with minimal adverse effects. Copyright © 2015 Elsevier España, S.L.U. and AEDV. All rights reserved.
Energy performance of semi-transparent PV modules for applications in buildings
NASA Astrophysics Data System (ADS)
Fung, Yu Yan
Owing to the increasing awareness on energy conservation and environmental protection, building-integrated photovoltaic (BIPV) has been developed rapidly in the past decade. A number of research studies have been conducted on the energy performance of BIPV systems. However, most of the previous studies focused on the systems that incorporated with opaque type PV modules, little attention has been devoted to semi-transparent type PV modules, which have been commonly integrated in modern architectures. This thesis aims at evaluating the energy performance of the semi-transparent BIPV modules, including heat gains to the indoor environment, power generation from the PV modules and daylight utilization. Solar radiation intensity on PV module's surfaces is an essential parameter for assessing energy performance of the PV modules. Different slope solar radiation models are analyzed and compared. The model that best suits Hong Kong situations is selected for the further development of the energy performance of the BIPV modules. The optimum orientation and tilted angle are determined in the analysis. In addition to the solar radiation models, a detailed investigation on the heat gain through the semi-transparent BIPV modules is carried out in this study. A one-dimensional transient heat transfer model, the SPVHG model, for evaluating the thermal performance of the semi-transparent BIPV modules is developed. The SPVHG model considers in detail the energy that is transmitted, absorbed and reflected in each element of the BIPV modules such as solar cells and glass layers. A computer program of the model is written accordingly. By applying the SPVHG model, the heat gain through the semi-transparent BIPV module of any thickness can be determined for any solar irradiance level. The annual performance can also be assessed by inputting annual weather data to the model. In order to verify the SPVHG model, laboratory tests have been carried out on semi-transparent BIPV modules. A well-insulated calorimeter box and an adjustable steady-state type solar simulator which can provide up to 1600 W/m2 have been used in the tests. Energy that transmitted through the semi-transparent BIPV modules and entered the calorimeter box was evaluated. It was found that the experimental results and the simulated results support each other. The SPVHG model is validated and can be used for further studies. Other than heat transfer, power production and the daylight utilization are also the vital parts in the energy performance assessment of the semi-transparent BIPV module for applications in building facades. Power generation models of both opaque and semi-transparent BIPV modules are investigated in this study. In order to test the validity of the power generation model, measurements on a BIPV system of an existing building are carried out. The measurement results reveal a good validity of the power generation model. Only a minor modification to the model is required. The daylight utilization is evaluated by using an indoor illuminance model. The model estimates the mean internal illuminance on the working plane of a room when there is both sunlight and skylight. Consequently, the power saving due to the daylight utilization can be determined. By using the SPVHG model together with the power generation model and the indoor illuminance model, the energy performance, in terms of electricity benefit, of building facades that incorporated with semi-transparent BIPV modules is evaluated. Different scenarios are studied by changing various parameters such as the window to wall ratios, thickness and efficiency of the solar cells. The results show that the solar cells within the semi-transparent BIPV modules significantly reduce the solar heat gain and thus reduce the power consumption of air-conditioning systems. Taking into account the impacts of PV electricity generation and daylight utilization, the optimum solar cell area ratio in the PV modules varies from 0.7 to 0.9 for different window-to-wall ratios of the building facade. The largest net electricity benefit of the BIPV facade under the simulation conditions is around 120 kWh/m 2. The SPVHG model developed in this study is a precise model for calculating the amount of heat gains through the semi-transparent BIPV modules. By considering also the power generation and daylight utilization, the electricity benefit of different BIPV facade configurations can be simulated. This information should help engineers predict the cooling load due to the BIPV facade and thus review their designs for energy efficiency optimization. On the whole, the results of this study provide valuable reference to local engineers, designers and professionals for efficient BIPV facade applications.
Autonomous physics-based color learning under daylight
NASA Astrophysics Data System (ADS)
Berube Lauziere, Yves; Gingras, Denis J.; Ferrie, Frank P.
1999-09-01
An autonomous approach for learning the colors of specific objects assumed to have known body spectral reflectances is developed for daylight illumination conditions. The main issue is to be able to find these objects autonomously in a set of training images captured under a wide variety of daylight illumination conditions, and to extract their colors to determine color space regions that are representative of the objects' colors and their variations. The work begins by modeling color formation under daylight using the color formation equations and the semi-empirical model of Judd, MacAdam and Wyszecki (CIE daylight model) for representing the typical spectral distributions of daylight. This results in color space regions that serve as prior information in the initial phase of learning which consists in detecting small reliable clusters of pixels having the appropriate colors. These clusters are then expanded by a region growing technique using broader color space regions than those predicted by the model. This is to detect objects in a way that is able to account for color variations which the model cannot due to its limitations. Validation on the detected objects is performed to filter out those that are not of interest and to eliminate unreliable pixel color values extracted from the remaining ones. Detection results using the color space regions determined from color values obtained by this procedure are discussed.
The energy performance of prototype holographic glazings
NASA Astrophysics Data System (ADS)
Papamichael, K.; Beltran, L.; Furler, R.; Lee, E. S.; Selkowitz, S.; Rubin, M.
1993-02-01
We report on the simulation of the energy performance of prototype holographic glazings in commercial office buildings in a California climate. These prototype glazings, installed above conventional side windows, are designed to diffract the transmitted solar radiation and reflect it off the ceiling, providing adequate daylight illumination for typical office tasks up to 10m from the window. In this study, we experimentally determined a comprehensive set of solar-optical properties and characterized the contribution of the prototype holographic glazings to workplane illuminance in a scale model of a typical office space. We then used the scale model measurements to simulate the energy performance of the holographic glazings over the course of an entire year for four window orientations (North, East, South and West) for the inland Los Angeles climate, using the DOE-2.lD building energy analysis computer program. The results of our experimental analyses indicate that these prototype holographic glazings diffract only a small fraction of the incident light. The results of this study indicate that these prototype holographic glazings will not save energy in commercial office buildings. Their performance is very similar to that of clear glass, which, through side windows, cannot efficiently illuminate more than a 4-6 m depth of a building's perimeter, because the cooling penalties due to solar heat gain are greater than the electric lighting savings due to daylighting.
Tomás-Velázquez, A; Redondo, P
2017-05-01
Actinic keratosis is a precursor lesion to the most common nonmelanoma skin cancer. Conventional photodynamic therapy (PDT) has been shown to be effective, but the procedure is time-consuming, can be very painful, and requires infrastructure. These shortcomings led to the emergence of daylight PDT. To obtain a global estimate of efficacy, we undertook a systematic literature review and performed a meta-analysis of the available evidence on the efficacy and safety of daylight PDT as compared to conventional PDT in the treatment of actinic keratosis and/or field cancerization. The conclusion is that the difference in efficacy is clinically negligible (global estimate of the mean response rate difference, -3.69%; 95% CI, -6.54% to -0.84%). The adverse effects of daylight PDT are mild and localized (79% of patients report no discomfort), and patients report less pain (P<.001). Daylight PDT gives good to excellent cosmetic results in more than 90% of patients, and patient satisfaction is greater (P<.001). Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.
Literature Review of the Effects of Natural Light on Building Occupants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Edwards, L.; Torcellini, P.
This paper presents summary findings from a literature search of the term ''daylighting''-using natural light in a building to offset or replace electric lighting. According to the Department of Energy's Office of Building Technology, State and Community Programs 2000 BTS Core Databook, in 1998, commercial buildings consumed 32% of the total electricity in the United States, of which more than one-third went to lighting. Using daylighting systems and turning off the lights will help reduce this energy load. Electrical lighting adds to both the electrical and cooling loads in a commercial building. Utility costs can be decreased when daylighting ismore » properly designed to replace electrical lighting. Along with the importance of energy savings, studies have demonstrated the non-energy-related benefits of daylighting. We compiled the data from books, periodicals, Internet articles, and interviews. The books, periodicals, and Internet articles provided the background information used to identify the main subjects of the paper. The interviews provided us with details related to specific buildings and companies that have integrated daylighting into their buildings.« less
1999-09-20
c o i b f t c c c c w n c s p t s Calculating correlated color temperatures across the entire gamut of daylight and skylight chromaticities Javier...temperature ~CCT!, yet existing equations for calculating CCT from chromaticity coordinates span only part of this range. To improve both the gamut and accuracy...00-1999 to 00-00-1999 4. TITLE AND SUBTITLE Calculating correlated color temperatures across the entire gamut of daylight and skylight
47 CFR 73.99 - Presunrise service authorization (PSRA) and postsunset service authorization (PSSA).
Code of Federal Regulations, 2013 CFR
2013-10-01
... authorization. (c) Extended Daylight Saving Time Pre-Sunrise Authorizations: (1) Between the first Sunday in... presunrise operations during extended daylight saving time and shall issue conforming authorizations. These...
47 CFR 73.99 - Presunrise service authorization (PSRA) and postsunset service authorization (PSSA).
Code of Federal Regulations, 2011 CFR
2011-10-01
... authorization. (c) Extended Daylight Saving Time Pre-Sunrise Authorizations: (1) Between the first Sunday in... presunrise operations during extended daylight saving time and shall issue conforming authorizations. These...
Mountain Retail Stores Become Showcase for Solar Energy
-seam metal roof, a transpired solar collector (solar wall), daylighting, energy efficient windows and during daytime hours. The Bighorn Center's final design includes clerestory windows for daylighting and a
A Study on the Optimal Duration of Daylight Saving Time (DST) in Korea
NASA Astrophysics Data System (ADS)
Mihn, Byeong-Hee; Ahn, Young Sook; Kim, Dong-Bin; Yang, Hong-Jin
2009-09-01
Daylight saving time aims at spending effective daylight in summer season. Korea had enforced daylight saving time twelve times from 1948 to 1988. Since 1988, it is not executed, but it is recently discussed the resumption of DST. In this paper, we investigate the trend of DST in other countries, review the history of DST in Korea, and suggest the optimal DST duration in terms of astronomical aspects (times of sunrise and sunset). We find that the starting day of DST in Korea is apt for the second Sunday in May or the second Sunday in April according to the time of sunrise or to the difference between Korean standard meridian and observer's, respectively. We also discuss time friction that might be caused by time difference between DST and Korea Standard Time (KST).
Super Blood Moon Lunar Eclipse
2017-12-08
What time will you be able to view the Super Moon Eclipse? The images below show times to view it for Eastern Daylight Time (EDT), Central Daylight Time (CDT), Mountain Daylight Time (MDT) and Pacific Daylight Time (PDT). All of South America and most of North and Central America will see the entire eclipse, while those west of roughly 120°W will see it in progress at moonrise. You won’t need special equipment to see it. Just go outside and look up! NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
The impact of translucent fabric shades and control strategies on energy savings and visual quality
NASA Astrophysics Data System (ADS)
Wankanapon, Pimonmart
Translucent fabric shades provide opportunities for building occupants to control sunlight penetration for heat reduction, thermal comfort, and visual quality. Regulating shades affects building energy and can potentially reduce the size of mechanical cooling systems. Shades are not normally included in energy model studies during the design process, even though shades potential impact energy use. This is because the occupants normally leave shades closed a large fraction of the time, but models are generally performed with no shades. Automatic shade control is now available, so it is necessary to understand the impact of shades on visual quality and their energy saving potential in order to optimize their overall performance. There are very limited studies that have address shades and their integrated performance on energy consumption and visual quality. Most of these do not reflected modern shade types and their application. The goals of this study are: First, to determine the impact of shades on total, heating, cooling and lighting energy savings with different design and operation parameters. Second, to study and develop different automatic shade control strategies to promote and optimize energy savings and visual quality. A simulation-based approach using EnergyPlus in a parametric study provide better understanding energy savings under different shade conditions. The parametric runs addressed various building parameters such as geometry, orientation, site climate, glazing/shade properties, and shade control strategies with integrated lighting control. The impact of shades was determined for total building and space heating, cooling and lighting energy savings. The effect of shades on visual quality was studied using EnergyPlus, AGI32 and DAYSIM for several indices such as daylight glare index (DGI), work plane illuminance, luminance ratios and view. Different shade control strategies and integrated lighting control were considered with two translucent fabric shade colors. The results clearly show the benefit of automatic shade control strategies with integrated lighting control over a condition when shades are closed all day. The main contributor to the total energy savings is from lighting energy savings, followed by cooling energy savings. Shades provide greater benefit in a hot climate and in a moderate climate than in a cold climate. Different control strategies provide savings in the range of 7-35% for annual total space energy with higher savings with light colored shades. Control strategies of shades should be selected and optimized based on climate, orientation, window area, and window/shade properties. High performance glazings, when equipped with shades, show lower energy savings when compared to standard glazings. High transmittance/reflectance shades, such as white shades, perform better than dark shades in most of the cases due to higher lighting energy savings obtained with the automatic electric lighting control and the resulting cooling energy savings from rejection of some solar energy and a reduction in the heat from lights. A South orientation showed the least benefit of automatic control of shades when compare to other orientations due to the large fraction of time shades are required to provide visual comfort. Under automatic shade control, energy savings are higher the more often the shades can be raised. The different automatic control strategies present tradeoffs between energy savings and comfort. With regard to visual quality, daylight quality assessments on view, glare, luminance ratios, and UDI can be used to assess shade control strategies. Automatic shade control can increase the number of view hours while controlling sunlight penetration. With automatic shade control, more daylight hours can be provided within the beneficial range of 100-2000 lux compared to shades that are closed all day. For a person facing the window, discomfort glare is likely to increase the more often the shades are raised. Keeping the shades down ensures an acceptable glare condition, but limits energy savings. Luminance ratios are another metric that can be used to assess shade performance. With white shades, the luminance ratios between the task and proximate surfaces are improved. Dark shades help improve the luminance ratios between the task and distant surfaces. When the shades are left open, even with no direct sunlight in the space, task to window luminance ratios will often exceed 1:10.
2012-09-01
pier and are exposed to salt water, wind , and adverse weather conditions. Utilities include electricity, potable water, and communication. Other...the NPTU Charleston piers (NOAA 2010). Daylight-only ship traffic extends upstream as far as the Nucor Steel Plant, accessing a slip for ocean-going...produced by the reactor plant is transmitted through the ship’s main engine turbine to a water break which simulates the action of a propeller without
Effective Energy Simulation and Optimal Design of Side-lit Buildings with Venetian Blinds
NASA Astrophysics Data System (ADS)
Cheng, Tian
Venetian blinds are popularly used in buildings to control the amount of incoming daylight for improving visual comfort and reducing heat gains in air-conditioning systems. Studies have shown that the proper design and operation of window systems could result in significant energy savings in both lighting and cooling. However, there is no convenient computer tool that allows effective and efficient optimization of the envelope of side-lit buildings with blinds now. Three computer tools, Adeline, DOE2 and EnergyPlus widely used for the above-mentioned purpose have been experimentally examined in this study. Results indicate that the two former tools give unacceptable accuracy due to unrealistic assumptions adopted while the last one may generate large errors in certain conditions. Moreover, current computer tools have to conduct hourly energy simulations, which are not necessary for life-cycle energy analysis and optimal design, to provide annual cooling loads. This is not computationally efficient, particularly not suitable for optimal designing a building at initial stage because the impacts of many design variations and optional features have to be evaluated. A methodology is therefore developed for efficient and effective thermal and daylighting simulations and optimal design of buildings with blinds. Based on geometric optics and radiosity method, a mathematical model is developed to reasonably simulate the daylighting behaviors of venetian blinds. Indoor illuminance at any reference point can be directly and efficiently computed. They have been validated with both experiments and simulations with Radiance. Validation results show that indoor illuminances computed by the new models agree well with the measured data, and the accuracy provided by them is equivalent to that of Radiance. The computational efficiency of the new models is much higher than that of Radiance as well as EnergyPlus. Two new methods are developed for the thermal simulation of buildings. A fast Fourier transform (FFT) method is presented to avoid the root-searching process in the inverse Laplace transform of multilayered walls. Generalized explicit FFT formulae for calculating the discrete Fourier transform (DFT) are developed for the first time. They can largely facilitate the implementation of FFT. The new method also provides a basis for generating the symbolic response factors. Validation simulations show that it can generate the response factors as accurate as the analytical solutions. The second method is for direct estimation of annual or seasonal cooling loads without the need for tedious hourly energy simulations. It is validated by hourly simulation results with DOE2. Then symbolic long-term cooling load can be created by combining the two methods with thermal network analysis. The symbolic long-term cooling load can keep the design parameters of interest as symbols, which is particularly useful for the optimal design and sensitivity analysis. The methodology is applied to an office building in Hong Kong for the optimal design of building envelope. Design variables such as window-to-wall ratio, building orientation, and glazing optical and thermal properties are included in the study. Results show that the selected design values could significantly impact the energy performance of windows, and the optimal design of side-lit buildings could greatly enhance energy savings. The application example also demonstrates that the developed methodology significantly facilitates the optimal building design and sensitivity analysis, and leads to high computational efficiency.
Teaching Science: Beats the Daylight Out of Me.
ERIC Educational Resources Information Center
Leyden, Michael B.
1995-01-01
Presents activities for observing, measuring, collecting, and graphing data about times of sunrise and sunset to teach an understanding about arrival of Daylight Savings Time in April. Also discusses seasonal affective disorder (SAD). (TM)
Bogers, Jan P.A.M.; Bostoen, Tijmen; Broekman, Theo G.
2016-01-01
Low vitamin D levels are associated with schizophrenia, but the possible association between vitamin D levels and illness severity or duration of exposure to daylight has barely been investigated. To compare vitamin D levels in therapy-refractory severely ill schizophrenia patients and members of staff. To investigate the influence of daylight exposure on vitamin D levels in patients. Vitamin D was measured in patients with therapy-resistant schizophrenia in April, after the winter, and in patients and staff members in June, after an exceptionally sunny spring. Vitamin D levels in April and June were compared in patients, and levels in June were compared in patients and staff. The influence of daylight was taken into account by comparing the time patients spent outdoors during the day with the recommended minimum time for adequate vitamin D synthesis, and by comparing time spent outdoors in patients and staff. Patients had high rates of vitamin D deficiency (79-90%) and lower levels of vitamin D than staff members (p < 0.001), independent of skin pigmentation. In patients, vitamin D levels did not normalize, despite the considerably longer than recommended exposure of the skin to daylight (p < 0.001) and the longer exposure in patients than in staff members (p = 0.003). The vitamin D deficiency of therapy-resistant schizophrenia patients is pronounced and cannot be explained by differences in skin pigmentation or by an inactive, indoor lifestyle on the ward. Even theoretically sufficient exposure of the patients to daylight did not ameliorate the low vitamin D levels. While vitamin D deficiency probably plays a role in somatic health problems, it may also play a role in schizophrenia. Interestingly, exposure to daylight during an unusually sunny spring was not sufficient to correct the vitamin D deficiency seen in the patients. This emphasizes the need to measure and correct vitamin D levels in these patients.
Variable area light reflecting assembly
Howard, T.C.
1986-12-23
Device is described for tracking daylight and projecting it into a building. The device tracks the sun and automatically adjusts both the orientation and area of the reflecting surface. The device may be mounted in either a wall or roof of a building. Additionally, multiple devices may be employed in a light shaft in a building, providing daylight to several different floors. The preferred embodiment employs a thin reflective film as the reflecting device. One edge of the reflective film is fixed, and the opposite end is attached to a spring-loaded take-up roller. As the sun moves across the sky, the take-up roller automatically adjusts the angle and surface area of the film. Additionally, louvers may be mounted at the light entrance to the device to reflect incoming daylight in an angle perpendicular to the device to provide maximum reflective capability when daylight enters the device at non-perpendicular angles. 9 figs.
Variable area light reflecting assembly
Howard, Thomas C.
1986-01-01
Device for tracking daylight and projecting it into a building. The device tracks the sun and automatically adjusts both the orientation and area of the reflecting surface. The device may be mounted in either a wall or roof of a building. Additionally, multiple devices may be employed in a light shaft in a building, providing daylight to several different floors. The preferred embodiment employs a thin reflective film as the reflecting device. One edge of the reflective film is fixed, and the opposite end is attached to a spring-loaded take-up roller. As the sun moves across the sky, the take-up roller automatically adjusts the angle and surface area of the film. Additionally, louvers may be mounted at the light entrance to the device to reflect incoming daylight in an angle perpendicular to the device to provide maximum reflective capability when daylight enters the device at non-perpendicular angles.
Daylight levels during the solar eclipse of 11 August 1999
NASA Astrophysics Data System (ADS)
Darula, S.; Kambezidis, H. D.; Kittler, R.
Solar eclipses are unique phenomena not only for astronomical and space observations but also for terrestrial; they create unique conditions of sunbeam blockage which cause not only the reduction of direct sunlight but also the dimming of skylight from the whole sky vault. Very favorable conditions were met during the recent August 1999 solar eclipse in Athens, Greece and Bratislava, Slovakia. General class daylight stations operate within the International Daylight Measurements Program in the two cities. One-minute data of global/diffuse illuminance and zenith luminance from those stations have been used to provide information about their levels and the daylight reduction rate during the eclipse. An approximate formula for the estimation of sunlight and skylight illuminance levels as well as zenith luminance using relative luminance sky patterns is also presented in this work. To achieve this, recently developed sky standards together with their parameterizations are utilized.
Designed To Maximize Learning and Minimize Costs.
ERIC Educational Resources Information Center
Dolan, Thomas G.
2002-01-01
Describes how the Durant Road Middle School in Raleigh, North Carolina sets a new standard in environmental school design. "Daylighting," bringing daylight into the building for psychological, health, and energy-saving benefits, plays a central role in the design. (EV)
Jin, Zhenong; Zhuang, Qianlai; Tan, Zeli; Dukes, Jeffrey S; Zheng, Bangyou; Melillo, Jerry M
2016-09-01
Stresses from heat and drought are expected to increasingly suppress crop yields, but the degree to which current models can represent these effects is uncertain. Here we evaluate the algorithms that determine impacts of heat and drought stress on maize in 16 major maize models by incorporating these algorithms into a standard model, the Agricultural Production Systems sIMulator (APSIM), and running an ensemble of simulations. Although both daily mean temperature and daylight temperature are common choice of forcing heat stress algorithms, current parameterizations in most models favor the use of daylight temperature even though the algorithm was designed for daily mean temperature. Different drought algorithms (i.e., a function of soil water content, of soil water supply to demand ratio, and of actual to potential transpiration ratio) simulated considerably different patterns of water shortage over the growing season, but nonetheless predicted similar decreases in annual yield. Using the selected combination of algorithms, our simulations show that maize yield reduction was more sensitive to drought stress than to heat stress for the US Midwest since the 1980s, and this pattern will continue under future scenarios; the influence of excessive heat will become increasingly prominent by the late 21st century. Our review of algorithms in 16 crop models suggests that the impacts of heat and drought stress on plant yield can be best described by crop models that: (i) incorporate event-based descriptions of heat and drought stress, (ii) consider the effects of nighttime warming, and (iii) coordinate the interactions among multiple stresses. Our study identifies the proficiency with which different model formulations capture the impacts of heat and drought stress on maize biomass and yield production. The framework presented here can be applied to other modeled processes and used to improve yield predictions of other crops with a wide variety of crop models. © 2016 John Wiley & Sons Ltd.
Year-Round Daylight Saving Time Study : Volume 2. Supporting Studies
DOT National Transportation Integrated Search
1975-06-01
This volume contains detailed background material in support of findings of the Interim Report. It includes the findings of a survey of attifudes towards daylight saving conducted by the National Opinion Research Center; description of sunrise and su...
The Effects of Primary Light Sources on Worker Performance and Alertness
NASA Technical Reports Server (NTRS)
Wong, Lily; Caddick, Zachary; Kuriyagawa, Yukiyo; Flynn-Evans, Erin
2017-01-01
Traditional office buildings use a variety of primary light sources (e.g., LED/fluorescent lights). As interest in LEED certified office buildings increase and research has shown that enhanced lighting design improves human performance and alertness (Viola et al., 2008; Juslén & Tenner, 2005; Edwards & Torcellini, 2002), more office buildings are incorporating a daylighting design. We investigated the differences between employee performance and alertness in two different building types (daylight vs. artificial light). We hypothesized that employee performance and sleep duration would be improved in a building designed to increase exposure to natural daylight compared to traditional office settings.
NASA Astrophysics Data System (ADS)
Ludman, Jacques E.; Riccobono, Juanita R.; Savant, Gajendra D.; Jannson, Joanna L.; Campbell, Eugene W.; Hall, Robyn
1995-09-01
Daylighting techniques are an effective means of reducing both lighting and cooling costs; however, many of the standard techniques have flaws which reduce their effectiveness. Daylighting holograms are an efficient and effective method for diffracting sunlight up onto the ceiling, deep in a room, without diffracting the light at eye-level. They need only cover the top half of a window to produce significant energy savings. They may be used as part of a new glazing system or as a retrofit to existing windows. These holograms are broadband and are able to passively track the movement of the sun across the sky, throughout the day and year.
Daylight exposure and the other predictors of burnout among nurses in a University Hospital.
Alimoglu, Mustafa Kemal; Donmez, Levent
2005-07-01
The purpose of the study was to investigate if daylight exposure in work setting could be placed among the predictors of job burnout. The sample was composed of 141 nurses who work in Akdeniz University Hospital in Antalya, Turkey. All participants were asked to complete a personal data collection form, the Maslach Burnout Inventory, the Work Related Strain Inventory and the Work Satisfaction Questionnaire to collect data about their burnout, work-related stress (WRS) and job satisfaction (JS) levels in addition to personal characteristics. Descriptive statistics, parametric and non-parametric tests and correlation analysis were used in statistical analyses. Daylight exposure showed no direct effect on burnout but it was indirectly effective via WRS and JS. Exposure to daylight at least 3h a day was found to cause less stress and higher satisfaction at work. Suffering from sleep disorders, younger age, job-related health problems and educational level were found to have total or partial direct effects on burnout. Night shifts may lead to burnout via work related strain and working in inpatient services and dissatisfaction with annual income may be effective via job dissatisfaction. This study confirmed some established predictors of burnout and provided data on an unexplored area. Daylight exposure may be effective on job burnout.
Developing a Telescope Simulator Towards a Global Autonomous Robotic Telescope Network
NASA Astrophysics Data System (ADS)
Giakoumidis, N.; Ioannou, Z.; Dong, H.; Mavridis, N.
2013-05-01
A robotic telescope network is a system that integrates a number of telescopes to observe a variety of astronomical targets without being operated by a human. This system autonomously selects and observes targets in accordance to an optimized target. It dynamically allocates telescope resources depending on the observation requests, specifications of the telescopes, target visibility, meteorological conditions, daylight, location restrictions and availability and many other factors. In this paper, we introduce a telescope simulator, which can control a telescope to a desired position in order to observe a specific object. The system includes a Client Module, a Server Module, and a Dynamic Scheduler module. We make use and integrate a number of open source software to simulate the movement of a robotic telescope, the telescope characteristics, the observational data and weather conditions in order to test and optimize our system.
ERIC Educational Resources Information Center
Kennedy, Mike
2007-01-01
In recent years, more education administrators and designers have embraced the potential benefits of daylighting. They have been persuaded that using natural light to illuminate facilities enables schools and universities to conserve energy and provide a learning environment in which students perform better. For daylighting advocates, the…
So, Rita; Teakles, Andrew; Baik, Jonathan; Vingarzan, Roxanne; Jones, Keith
2018-05-01
Visibility degradation, one of the most noticeable indicators of poor air quality, can occur despite relatively low levels of particulate matter when the risk to human health is low. The availability of timely and reliable visibility forecasts can provide a more comprehensive understanding of the anticipated air quality conditions to better inform local jurisdictions and the public. This paper describes the development of a visibility forecasting modeling framework, which leverages the existing air quality and meteorological forecasts from Canada's operational Regional Air Quality Deterministic Prediction System (RAQDPS) for the Lower Fraser Valley of British Columbia. A baseline model (GM-IMPROVE) was constructed using the revised IMPROVE algorithm based on unprocessed forecasts from the RAQDPS. Three additional prototypes (UMOS-HYB, GM-MLR, GM-RF) were also developed and assessed for forecast performance of up to 48 hr lead time during various air quality and meteorological conditions. Forecast performance was assessed by examining their ability to provide both numerical and categorical forecasts in the form of 1-hr total extinction and Visual Air Quality Ratings (VAQR), respectively. While GM-IMPROVE generally overestimated extinction more than twofold, it had skill in forecasting the relative species contribution to visibility impairment, including ammonium sulfate and ammonium nitrate. Both statistical prototypes, GM-MLR and GM-RF, performed well in forecasting 1-hr extinction during daylight hours, with correlation coefficients (R) ranging from 0.59 to 0.77. UMOS-HYB, a prototype based on postprocessed air quality forecasts without additional statistical modeling, provided reasonable forecasts during most daylight hours. In terms of categorical forecasts, the best prototype was approximately 75 to 87% correct, when forecasting for a condensed three-category VAQR. A case study, focusing on a poor visual air quality yet low Air Quality Health Index episode, illustrated that the statistical prototypes were able to provide timely and skillful visibility forecasts with lead time up to 48 hr. This study describes the development of a visibility forecasting modeling framework, which leverages the existing air quality and meteorological forecasts from Canada's operational Regional Air Quality Deterministic Prediction System. The main applications include tourism and recreation planning, input into air quality management programs, and educational outreach. Visibility forecasts, when supplemented with the existing air quality and health based forecasts, can assist jurisdictions to anticipate the visual air quality impacts as perceived by the public, which can potentially assist in formulating the appropriate air quality bulletins and recommendations.
Sanclemente, G; Mancilla, G A; Hernandez, G
2016-04-01
Daylight PDT (dPDT) is easy to use and does not require light equipment. Such therapy has been exhaustively proved to be successful in the treatment of actinic keratosis, but its use in skin photodamage remains unclear. To evaluate dPDT's efficacy in skin facial photodamage. This was a parallel-group double-blind, randomized placebo-controlled trial. Sixty participants with symmetric facial photodamage were allocated to topical methyl aminolevulinate (MAL) and daylight vs. matching placebo and daylight. Primary outcome was global photodamage improvement/failure 1 month after the third session. Secondary outcomes included: pain evaluation; specific photodamage severity scores; sun irradiance quantification and Skindex-29 scores. Adverse events were also investigated. Primary analysis included all randomized patients. All patients sun-exposed for 120min in 3 sessions. The risk of failure was lower in the MAL-dPDT group than in the placebo plus daylight group (RR: 0.18; 95% CI: 0.08-0.41). Mean solar irradiance (W/m(2)) during the first, second and third sessions was 480.82, 430.07 and 435.84, respectively. Items 5 and 14 of Skindex-29 in the MAL-dPDT group showed statistical significant differences. Two patients in the MAL-dPDT group had serious and non-serious events not directly related to the product. dPDT with MAL was un-painful, effective and safe for the treatment of facial photodamage. Herpes simplex prophylaxis should be considered before sessions. Copyright © 2015 AEDV. Published by Elsevier España, S.L.U. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hoffmann, Sabine; Lee, Eleanor
Exterior shades are highly efficient for reducing solar load in commercial buildings. Their impact on net energy use depends on the annual energy balance of heating, cooling, fan and lighting energy. This paper discusses the overall energy use intensity of various external shading systems for a prototypical large office building split into the different types of energy use and for different orientations and window sizes. Lighting energy was calculated for a constant lighting power as well as for dimmed lighting fixtures (daylighting control). In Section 3, slat angles and solar cut-off angles were varied for fixed exterior slat shading systems.more » While the most light-blocking shades performed best for the case without daylighting controls, the optimum cut-off angle with daylighting controls was found to be 30 deg for the office building prototype used in Chicago and Houston. For large window-to-wall (WWR) ratios, window related annual energy use could be reduced by at least 70 % without daylighting control and by a minimum of 86 % with daylighting control in average over all orientations. The occurrence of discomfort glare was is considered in Section 4 of the paper, which looks at the performance of commercially available exterior shading systems when an interior shade is used in addition to the exterior shade during hours when occupants would experience discomfort glare. Glare control impacts overall energy use intensity significantly for exterior shades with high transmittance, especially when daylighting controls are used. In these cases, exterior shades are only beneficial for window-to-wall areas ≥ 45% in the hot Houston climate. For smaller windows and in a heating/cooling climate like Chicago, exterior shades can increase energy consumption« less
Energy efficiency buildings program
NASA Astrophysics Data System (ADS)
1981-05-01
Progress is reported in developing techniques for auditing the energy performance of buildings. The ventilation of buildings and indoor air quality is discussed from the viewpoint of (1) combustion generated pollutants; (2) organic contaminants; (3) radon emanation, measurements, and control; (4) strategies for the field monitoring of indoor air quality; and (5) mechanical ventilation systems using air-to-air heat exchanges. The development of energy efficient windows to provide optimum daylight with minimal thermal losses in cold weather and minimum thermal gain in hot weather is considered as well as the production of high frequency solid state ballasts for fluorescent lights to provide more efficient lighting at a 25% savings over conventional core ballasts. Data compilation, analysis, and demonstration activities are summarized.
HORIZONTAL HYBRID SOLAR LIGHT PIPE: AN INTEGRATED SYSTEM OF DAYLIGHT AND ELECTRIC LIGHT
This project will test the feasibility of an advanced energy efficient perimeter lighting system that integrates daylighting, electric lighting, and lighting controls to reduce electricity consumption. The system is designed to provide adequate illuminance levels in deep-floor...
NASA Technical Reports Server (NTRS)
Brook, M.
1986-01-01
An optical lightning detector was constructed and flown, along with Vinton cameras and a Fairchild Line Scan Spectrometer, on a U-2 during the summer of 1979. The U-2 lightning data was obtained in daylight, and was supplemented with ground truth taken at Langmuir Laboratory. Simulations were prepared as required to establish experiment operating procedures and science training for the astronauts who would operate the Night/Day Optical Survey of Thunderstorm Lightning (NOSL) equipment during the STS-2 NOSL experiment on the Space Shuttle. Data was analyzed and papers were prepared for publication.
Spectral Analysis of the Effects of Daylight Saving Time on Motor Vehicle Fatal Traffic Accidents
DOT National Transportation Integrated Search
1977-04-01
This report shows that Daylight Saving Time (DST) reduces the number of persons killed in motor vehicle fatal traffic accidents by about one percent. This estimate is based on a spectral (Fourier) analysis of these fatalities which utilizes a filteri...
ERIC Educational Resources Information Center
Willi, John G.
2003-01-01
Describes how one elementary school was designed to be a flexible, innovative campus that connects learning and the learning environment. The celebration of nature is carried out in many ways within the building. Students are exposed to great vistas from every interior location. Daylighting is infused throughout the school to reinforce the desire…
Field Commissioning of a Daylight-Dimming Lighting System.
ERIC Educational Resources Information Center
Floyd, David B.; Parker, Danny S.
A Florida elementary school cafeteria, retrofitted with a fluorescent lighting system that dims in response to available daylight, was evaluated through real time measurement of lighting and air conditioning power, work plane illumination, and interior/exterior site conditions. The new system produced a 27 percent reduction in lighting power due…
75 FR 36089 - Payment System Risk Policy; Daylight Overdraft Posting Rules
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-24
... and includes only Accounts Receivable Entry (ARC), Back Office Conversion Entry (BOC), Point-of... account balance and daylight overdraft balance in Account Management Information (AMI), which is a service... under the authority delegated to the Board by the Office of Management and Budget. No collections of...
78 FR 64026 - Investigative Hearing
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-25
... Investigative Hearing. On Friday, May 17, 2013, at 6:01 p.m. eastern daylight time, eastbound Metro-North... $18.5 million. On Tuesday, May 28, 2013, at 11:57 a.m. eastern daylight time, Metro-North Railroad...; and Metro-North's organizational safety culture. Parties to the hearing include the Federal Railroad...
Brawley, Elizabeth C
2009-01-01
Good lighting is perhaps the most important and least understood element in designing healthcare environments. Both physically and mentally challenged individuals become more vulnerable and dependent on their environment to compensate for sensory impairments, including dimming eyesight, which interferes to some degree with daily activities as well as social and leisure activities - the things that provide emotional and social well-being. Too few building designs today result in lighting that meets the needs of these individuals, regardless of age. Typical lighting in most care environments is inadequate to meet lighting needs affecting both vision and the photobiological (non-visual) needs of synchronization of circadian rhythm, which impacts sleep and depression. Well-designed lighting is one of the most important design elements that will support an individual's ability to perform normal daily activities and decrease the level of disability associated with these impairments. Daylight contains the spectrum to which the circadian clock is most sensitive and provides higher light levels during the day. Easily accessible outdoor gardens encourage individuals outside, providing the necessary regular exposure to direct bright light that sunlight provides. The combination good interior lighting and regular daylight exposure contributes to regaining and maintaining an active and fulfilling lifestyle - greatly improving quality of life.
Window performance and building energy use: Some technical options for increasing energy efficiency
NASA Astrophysics Data System (ADS)
Selkowitz, Stephen
1985-11-01
Window system design and operation has a major impact on energy use in buildings as well as on occupants' thermal and visual comfort. Window performance will be a function of optical and thermal properties, window management strategies, climate and orientation, and building type and occupancy. In residences, heat loss control is a primary concern, followed by sun control in more southerly climates. In commercial buildings, the daylight provided by windows may be the major energy benefits but solar gain must be controlled so that increased cooling loads do not exceed daylighting savings. Reductions in peak electrical demand and HVAC system size may also be possible in well-designed daylighted buildings.
Automatic target detection using binary template matching
NASA Astrophysics Data System (ADS)
Jun, Dong-San; Sun, Sun-Gu; Park, HyunWook
2005-03-01
This paper presents a new automatic target detection (ATD) algorithm to detect targets such as battle tanks and armored personal carriers in ground-to-ground scenarios. Whereas most ATD algorithms were developed for forward-looking infrared (FLIR) images, we have developed an ATD algorithm for charge-coupled device (CCD) images, which have superior quality to FLIR images in daylight. The proposed algorithm uses fast binary template matching with an adaptive binarization, which is robust to various light conditions in CCD images and saves computation time. Experimental results show that the proposed method has good detection performance.
Colour Mixing Based on Daylight
ERIC Educational Resources Information Center
Meyn, Jan-Peter
2008-01-01
Colour science is based on the sensation of monochromatic light. In contrast to that, surface colours are caused by reflection of wide sections of the daylight spectrum. Non-spectral colours like magenta and purple appear homologous to colours with spectral hue, if the approach of mixing monochromatic light is abandoned. It is shown that a large…
Luminescent Solar Concentrator Daylighting
NASA Astrophysics Data System (ADS)
Bornstein, Jonathan G.
1984-11-01
Various systems that offer potential solutions to the problem of interior daylighting have been discussed in the literature. Virtually all of these systems rely on some method of tracking the sun along its azimuth and elevation, i.e., direct imaging of the solar disk. A simpler approach, however, involves a nontracking nonimaging device that effectively eliminates moving parts and accepts both the diffuse and direct components of solar radiation. Such an approach is based on a system that combines in a common luminaire the light emitted by luminescent solar concentrators (LSC), of the three primary colors, with a highly efficient artificial point source (HID metal halide) that automatically compensates for fluctuations in the LSC array via a daylight sensor and dimming ballast. A preliminary analysis suggests that this system could supply 90% of the lighting requirement, over the course of an 8 hour day, strictly from the daylight component under typical insolation con-ditions in the Southwest United States. In office buildings alone, the total aggregate energy savings may approach a half a quad annually. This indicates a very good potential for the realization of substantial savings in building electric energy consumption.
NASA Astrophysics Data System (ADS)
Murray, Patrick L.
Government programs designed to decrease resource consumption, improve productivity and capitalize on extended daylight hours in the summer have been developed and implemented throughout the world for nearly three hundred years. In 2005, The United States government adopted an extended daylight savings program that increases the number of weeks where the country observes Daylight Saving Time (DST) from 31 to 35 weeks. The program took effect in March 2007. Arguments in support of DST programs highlight the portion of electricity consumption attributed to residential lighting in the evening hours. Adjusting clocks forward by one hour in summer months is believed to reduce electricity consumption due to lighting and therefore significantly reduce residential energy consumption during the period of DST. This paper evaluates the efficacy of the changes to DST resulting from the Energy Policy Act of 2005. The study focuses on changes to household electricity consumption during the extended four weeks of DST. Arizona, one of two states that continue to opt out of DST serves as the study's control for a comparison with neighboring states, Colorado, Nebraska, Nevada, New Mexico, Oklahoma, Texas and Utah. Results from the regression analysis of a Difference in Difference model indicate that contrary to evaluations by Congress and the Department of Energy, the four week period of Extended Daylight Saving Time does not produce a significant decrease in per capita electricity consumption in Southwestern states.
NASA Astrophysics Data System (ADS)
Ekasiwi, S. N. N.; Antaryama, I. G. N.; Krisdianto, J.; Ulum, M. S.
2018-03-01
Classrooms in educational buildings require certain lighting requirements to serve teaching and learning activities during daytime. The most typical design is double sided opening in order to get good daylight distribution in the classroom. Using artificial light is essential to contribute the worse daylight condition. A short observation indicates that during the lecture time the light turned on, even in the daytime. That might result in wasting electrical energy. The aim of the study is to examine the type of classroom, which perform comfortable lighting environment as well as saving energy. This paper reports preliminary results of the study obtained from field observation and measurements. The use of energy and usage pattern of artificial lighting during the lecture is recorded and then the data evaluated to see the suitability of existing energy use to building energy standards. The daylighting design aspects have to be the first consideration. However, the similarity in WWR of the classroom, the Daylight Factor (DF) may differ. It depends on the room depth. The similarity of the increase of WWR and Ratio of openings to floor area do not directly correspond to the increase of DF. The outdoor condition of larger daylight access and the room depth are the influencing factors. Despite the similarity of physical type, usage pattern of the classroom imply the use of electrical energy for lighting. The results indicate the factors influencing lighting energy performance in correlation to their typologies
Goodman, Anna; Page, Angie S; Cooper, Ashley R
2014-10-23
It has been proposed that introducing daylight saving measures could increase children's physical activity, but there exists little research on this issue. This study therefore examined associations between time of sunset and activity levels, including using the bi-annual 'changing of the clocks' as a natural experiment. 23,188 children aged 5-16 years from 15 studies in nine countries were brought together in the International Children's Accelerometry Database. 439 of these children were of particular interest for our analyses as they contributed data both immediately before and after the clocks changed. All children provided objectively-measured physical activity data from Actigraph accelerometers, and we used their average physical activity level (accelerometer counts per minute) as our primary outcome. Date of accelerometer data collection was matched to time of sunset, and to weather characteristics including daily precipitation, humidity, wind speed and temperature. Adjusting for child and weather covariates, we found that longer evening daylight was independently associated with a small increase in daily physical activity. Consistent with a causal interpretation, the magnitude of these associations was largest in the late afternoon and early evening and these associations were also evident when comparing the same child just before and just after the clocks changed. These associations were, however, only consistently observed in the five mainland European, four English and two Australian samples (adjusted, pooled effect sizes 0.03-0.07 standard deviations per hour of additional evening daylight). In some settings there was some evidence of larger associations between daylength and physical activity in boys. There was no evidence of interactions with weight status or maternal education, and inconsistent findings for interactions with age. In Europe and Australia, evening daylight seems to play a causal role in increasing children's activity in a relatively equitable manner. Although the average increase in activity is small in absolute terms, these increases apply across all children in a population. Moreover, these small effect sizes actually compare relatively favourably with the typical effect of intensive, individual-level interventions. We therefore conclude that, by shifting the physical activity mean of the entire population, the introduction of additional daylight saving measures could yield worthwhile public health benefits.
Re-Analysis Report: Daylighting in Schools, Additional Analysis. Tasks 2.2.1 through 2.2.5.
ERIC Educational Resources Information Center
Heschong, Lisa; Elzeyadi, Ihab; Knecht, Carey
This study expands and validates previous research that found a statistical correlation between the amount of daylight in elementary school classrooms and the performance of students on standardized math and reading tests. The researchers reanalyzed the 19971998 school year student performance data from the Capistrano Unified School District…
ERIC Educational Resources Information Center
Grocoff, Paul N.
This report examines both electric lighting and daylighting, listing criteria to determine the correct equipment for a school renovation or building project. Specific topics examine use of prismatic lenses; parabolic louvers; and indirect lighting, including the cost savings of using indirect lighting. The report indicates there is no clear answer…
Change in the Classroom Deportment of Children Following Change From Daylight Saving Time.
ERIC Educational Resources Information Center
Hicks, Robert A.; And Others
1980-01-01
The deportment of each student in a third-grade classroom was rated by the teacher before and after the fall change from daylight savings time, to see if this disruption in circadian rhythms alters behavior. The deportment of boys improved significantly while the deportment of girls was significantly disrupted. (Author/SJL)
Effects of cardiothoracic physiotherapy on intrapulmonary shunt in abdominal surgical patients.
Ntoumenopoulos, George; Greenwood, Kenneth
1996-01-01
This study investigated the provision of additional evening physiotherapy on pulmonary complications and intrapulmonary shunt (Qs/Qt) after abdominal surgery. Thirty-one elderly patients received either daylight only or daylight plus evening physiotherapy for up to 48 hours. Physiotherapy included combinations of positioning, gravity assisted drainage, breathing exercises, manual techniques, coughing and airway suctioning. Measurements included Qs/Qt and post-operative pulmonary complications. While no significant difference in atelectasis was found, the post-operative Qs/Qt data averaged into six-hour time frames demonstrated significantly lower mean Qs/Qt for the daylight plus evening physiotherapy group between 18 and 24 hours post-surgery. Additional evening physiotherapy may reduce post-operative deterioration in gas exchange after major abdominal surgery.
Marionnet, Claire; Tricaud, Caroline; Bernerd, Françoise
2014-01-01
The link between chronic sun exposure of human skin and harmful clinical consequences such as photo-aging and skin cancers is now indisputable. These effects are mostly due to ultraviolet (UV) rays (UVA, 320–400 nm and UVB, 280–320 nm). The UVA/UVB ratio can vary with latitude, season, hour, meteorology and ozone layer, leading to different exposure conditions. Zenithal sun exposure (for example on a beach around noon under a clear sky) can rapidly induce visible and well-characterized clinical consequences such as sunburn, predominantly induced by UVB. However, a limited part of the global population is exposed daily to such intense irradiance and until recently little attention has been paid to solar exposure that does not induce any short term clinical impact. This paper will review different studies on non-extreme daily UV exposures with: (1) the characterization and the definition of the standard UV daylight and its simulation in the laboratory; (2) description of the biological and clinical effects of such UV exposure in an in vitro reconstructed human skin model and in human skin in vivo, emphasizing the contribution of UVA rays and (3) analysis of photoprotection approaches dedicated to prevent the harmful impact of such UV exposure. PMID:25546388
Marionnet, Claire; Tricaud, Caroline; Bernerd, Françoise
2014-12-23
The link between chronic sun exposure of human skin and harmful clinical consequences such as photo-aging and skin cancers is now indisputable. These effects are mostly due to ultraviolet (UV) rays (UVA, 320-400 nm and UVB, 280-320 nm). The UVA/UVB ratio can vary with latitude, season, hour, meteorology and ozone layer, leading to different exposure conditions. Zenithal sun exposure (for example on a beach around noon under a clear sky) can rapidly induce visible and well-characterized clinical consequences such as sunburn, predominantly induced by UVB. However, a limited part of the global population is exposed daily to such intense irradiance and until recently little attention has been paid to solar exposure that does not induce any short term clinical impact. This paper will review different studies on non-extreme daily UV exposures with: (1) the characterization and the definition of the standard UV daylight and its simulation in the laboratory; (2) description of the biological and clinical effects of such UV exposure in an in vitro reconstructed human skin model and in human skin in vivo, emphasizing the contribution of UVA rays and (3) analysis of photoprotection approaches dedicated to prevent the harmful impact of such UV exposure.
Zhou, Minghua; Yu, Jiaguo
2008-04-15
A simple method for preparing highly daylight-induced photoactive nanocrystalline C,N,S-tridoped TiO2 powders was developed by a solid-phase reaction. The as-prepared TiO2 powders were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectra, N2 adsorption-desorption measurements and transmission electron microscopy (TEM). The photocatalytic activity was evaluated by the photocatalytic oxidation of formaldehyde under daylight irradiation in air. The results show that daylight-induced photocatalytic activities of the as-prepared TiO2 powders were improved by C,N,S-tridoping. The C,N,S-tridoped TiO2 powders exhibited stronger absorption in the near UV and visible-light region with red shift in the band-gap transition. When the molar ratio of CS(NH2)2 to xerogel TiO2 powders (prepared by hydrolysis of Ti(OC4H9)4 in distilled water) (R) was kept in 3, the daylight-induced photocatalytic activities of the as-prepared C,N,S-tridoped TiO2 powders were about more than six times greater than that of Degussa P25 and un-doped TiO2 powders. The high activities of the C,N,S-tridoped TiO2 can be attributed to the results of the synergetic effects of strong absorption in the near UV and visible-light region, red shift in adsorption edge and two phase structures of un-doped TiO2 and C,N,S-tridoped TiO2.
NASA Astrophysics Data System (ADS)
Wadsworth, Adam J.
A method for passively detecting and imaging underwater targets using ambient noise as the sole source of illumination (named acoustic daylight) was successfully implemented in the form of the Acoustic Daylight Ocean Noise Imaging System (ADONIS). In a series of imaging experiments conducted in San Diego Bay, where the dominant source of high-frequency ambient noise is snapping shrimp, a large quantity of ambient noise intensity data was collected with the ADONIS (Epifanio, 1997). In a subset of the experimental data sets, fluctuations of time-averaged ambient noise intensity exhibited a diurnal pattern consistent with the increase in frequency of shrimp snapping near dawn and dusk. The same subset of experimental data is revisited here and the correlation time is estimated and analysed for sequences of ambient noise data several minutes in length, with the aim of detecting possible periodicities or other trends in the fluctuation of the shrimp-dominated ambient noise field. Using videos formed from sequences of acoustic daylight images along with other experimental information, candidate segments of static-configuration ADONIS raw ambient noise data were isolated. For each segment, the normalized intensity auto-correlation closely resembled the delta function, the auto-correlation of white noise. No intensity fluctuation patterns at timescales smaller than a few minutes were discernible, suggesting that the shrimp do not communicate, synchronise, or exhibit any periodicities in their snapping. Also presented here is a ADONIS-specific target recognition algorithm based on principal component analysis, along with basic experimental results using a database of acoustic daylight images.
Daylight Savings Time Transitions and the Incidence Rate of Unipolar Depressive Episodes.
Hansen, Bertel T; Sønderskov, Kim M; Hageman, Ida; Dinesen, Peter T; Østergaard, Søren D
2017-05-01
Daylight savings time transitions affect approximately 1.6 billion people worldwide. Prior studies have documented associations between daylight savings time transitions and adverse health outcomes, but it remains unknown whether they also cause an increase in the incidence rate of depressive episodes. This seems likely because daylight savings time transitions affect circadian rhythms, which are implicated in the etiology of depressive disorder. Therefore, we investigated the effects of daylight savings time transitions on the incidence rate of unipolar depressive episodes. Using time series intervention analysis of nationwide data from the Danish Psychiatric Central Research Register from 1995 to 2012, we compared the observed trend in the incidence rate of hospital contacts for unipolar depressive episodes after the transitions to and from summer time to the predicted trend in the incidence rate. The analyses were based on 185,419 hospital contacts for unipolar depression and showed that the transition from summer time to standard time were associated with an 11% increase (95% CI = 7%, 15%) in the incidence rate of unipolar depressive episodes that dissipated over approximately 10 weeks. The transition from standard time to summer time was not associated with a parallel change in the incidence rate of unipolar depressive episodes. This study shows that the transition from summer time to standard time was associated with an increase in the incidence rate of unipolar depressive episodes. Distress associated with the sudden advancement of sunset, marking the coming of a long period of short days, may explain this finding. See video abstract at, http://links.lww.com/EDE/B179.
11 CFR 100.19 - File, filed or filing (2 U.S.C. 434(a)).
Code of Federal Regulations, 2014 CFR
2014-01-01
... Time on the filing date, except that pre-election reports must have a postmark dated no later than 11:59 p.m. Eastern Standard/Daylight Time on the fifteenth day before the date of the election. (2... Standard/Daylight Time on the filing date. (d) 48-hour and 24-hour reports of independent expenditures—(1...
ERIC Educational Resources Information Center
Amasuomo, Japo Oweikeye Morto; Alio, Abigail Ngozi
2013-01-01
The study investigated daylight illumination in the school workshop as a determinant for effective students' task performance in workshop practice. 183 NCE Technical students in 300 Level which comprised of 73 and 112 students from Federal Colleges of Education (Technical), Asaba and Omoku, Nigeria respectively during the 2008/2009 academic…
Differences in geometry of pedestrian crashes in daylight and darkness.
Sullivan, John M; Flannagan, Michael J
2011-02-01
Previous studies have shown that increased risk in darkness is particularly great for pedestrian crashes, suggesting that attempts to improve headlighting should focus on factors that likely influence those crashes. The current analysis was designed to provide information about how details of pedestrian crashes may differ between daylight and darkness. All pedestrian crashes that occurred in daylight or dark conditions in Michigan during 2004 were analyzed in terms of the variables included in the State of Michigan crash database. Additional analysis of the narratives and diagrams in police accident reports was performed for a subset of 400 of those crashes-200 sampled from daylight and 200 sampled from darkness. Several differences were found that appear to be related to the characteristic asymmetry of low-beam headlamps, which (in the United States) distributes more light on the passenger's side than the driver's side of the vehicle. These results provide preliminary quantification of the how the photometric differences between the right and left sides of typical headlamps may affect pedestrian crash risk. The results suggest that efforts to provide supplemental forward vehicle lighting in turns may have safety benefits for pedestrians. Copyright © 2011 Elsevier Ltd. All rights reserved.
Kriszbacher, Ildikó; Bódis, József; Boncz, Imre; Koppan, Agnes; Koppan, Miklós
2010-04-01
We investigated whether the time of sunrise and the number of daylight hours have an effect on the seasonality, or the daily rhythm of heart attack mortality. We analyzed retrospectively data of patients admitted to hospitals with the diagnosis of heart attack (n=32,329) and patients who deceased of a heart attack (n=5142) between January 1, 2004 and December 31, 2005 in Hungary. Heart attack mortality was highest during winter, while lowest number of events was recorded during summer . The daily peak of diurnality was between 6:00 am and 12:00 pm (33.77%). A positive correlation was found between the time of sunrise, time of sunset and the mortality caused by myocardial infarction (p<0,01). In the analysis of the number of daylight hours and the heart attack mortality we found a negative correlation (r=-0.105, p<0.05). No significant difference was found between sexes and different age-groups in heart attack mortality. Our data suggest, that the occurrence and the mortality of heart attack may be related to the time of sunrise and the number of daylight hours. Copyright 2008 Elsevier Ireland Ltd. All rights reserved.
High-power lightweight external-cavity quantum cascade lasers
NASA Astrophysics Data System (ADS)
Day, Timothy; Takeuchi, Eric B.; Weida, Miles; Arnone, David; Pushkarsky, Michael; Boyden, David; Caffey, David
2009-05-01
Commercially available quantum cascade gain media has been integrated with advanced coating and die attach technologies, mid-IR micro-optics and telecom-style assembly and packaging to yield cutting edge performance. When combined into Daylight's external-cavity quantum cascade laser (ECqcL) platform, multi-Watt output power has been obtained. Daylight will describe their most recent results obtained from this platform, including high cw power from compact hermetically sealed packages and narrow spectral linewidth devices. Fiber-coupling and direct amplitude modulation from such multi-Watt lasers will also be described. In addition, Daylight will present the most recent results from their compact, portable, battery-operated "thermal laser pointers" that are being used for illumination and aiming applications. When combined with thermal imaging technology, such devices provide significant benefits in contrast and identification.
Psychological Effect of Daylighting on Behavior
NASA Astrophysics Data System (ADS)
Oyama, Yoshie
In order to facilitate use of daylighting in architectural design, we tried to measure the suitability of luminous environment for various behavior, including not only visual work but also refreshing and rest. An experiment was conducted with 7 luminous conditions including daylighting. The suitability of a luminous environment was measured by asking the subjects to select suitable activities and unsuitable behaviors from a given list of possible activities. The result showed the selection of unsuitable behaviors was more useful than the selection of suitable behaviors. Furthermore, lighting installations offering a steady luminous environments, were not suitable for many behaviors including refreshing and rest. The luminous environments which were bright but had some fluctuation and some non-uniformity of brightness, obtained by use of direct sunlight, were judged to be suitable for negotiating, refreshing, and meeting.
Hernández-Andrés, J; Lee, R L; Romero, J
1999-09-20
Natural outdoor illumination daily undergoes large changes in its correlated color temperature (CCT), yet existing equations for calculating CCT from chromaticity coordinates span only part of this range. To improve both the gamut and accuracy of these CCT calculations, we use chromaticities calculated from our measurements of nearly 7000 daylight and skylight spectra to test an equation that accurately maps CIE 1931 chromaticities x and y into CCT. We extend the work of McCamy [Color Res. Appl. 12, 285-287 (1992)] by using a chromaticity epicenter for CCT and the inverse slope of the line that connects it to x and y. With two epicenters for different CCT ranges, our simple equation is accurate across wide chromaticity and CCT ranges (3000-10(6) K) spanned by daylight and skylight.
A computer program for analyzing the energy consumption of automatically controlled lighting systems
NASA Astrophysics Data System (ADS)
1982-01-01
A computer code to predict the performance of controlled lighting systems with respect to their energy saving capabilities is presented. The computer program provides a mathematical model from which comparisons of control schemes can be made on an economic basis only. The program does not calculate daylighting, but uses daylighting values as input. The program can analyze any of three power input versus light output relationships, continuous dimming with a linear response, continuous dimming with a nonlinear response, or discrete stepped response. Any of these options can be used with or without daylighting, making six distinct modes of control system operation. These relationships are described in detail. The major components of the program are discussed and examples are included to explain how to run the program.
The effect of daylight versus darkness on driver sleepiness: a driving simulator study.
Ahlström, Christer; Anund, Anna; Fors, Carina; Åkerstedt, Torbjörn
2018-06-01
Driver sleepiness studies are often carried out with alert drivers during daytime and sleep-deprived drivers during night-time. This design results in a mixture of different factors (e.g. circadian effects, homeostatic effects, light conditions) that may confound the results. The aim of this study was to investigate the effect of light conditions on driver sleepiness. Thirty young male drivers (23.6 ± 1.7 years old) participated in a driving simulator experiment where they drove on a rural road. A 2 × 2 design was used with the conditions daylight versus darkness, and daytime (full sleep) versus night-time (sleep deprived). The results show that light condition had an independent effect on the sleepiness variables. The subjective sleepiness measured by Karolinska Sleepiness Scale was higher, lateral position more left-oriented, speed lower, electroencephalogram alpha and theta higher, and blink durations were longer during darkness. The number of line crossings did not change significantly with light condition. The day/night condition had profound effects on most sleepiness indicators while controlling for light condition. The number of line crossings was higher during night driving, Karolinska Sleepiness Scale was higher, blink durations were longer and speed was lower. There were no significant interactions, indicating that light conditions have an additive effect on sleepiness. In conclusion, Karolinska Sleepiness Scale and blink durations increase primarily with sleep deprivation, but also as an effect of darkness. Line crossings are mainly driven by the need for sleep and the reduced alertness at the circadian nadir. Lane position is, however, more determined by light conditions than by sleepiness. © 2017 European Sleep Research Society.
NASA Technical Reports Server (NTRS)
Klassen, Steve; Bugbee, Bruce
2005-01-01
Accurate shortwave radiation data is critical to evapotranspiration (ET) models used for developing irrigation schedules to optimize crop production while saving water, minimizing fertilizer, herbicide, and pesticide applications, reducing soil erosion, and protecting surface and ground water quality. Low cost silicon cell pyranometers have proven to be sufficiently accurate and robust for widespread use in agricultural applications under unobstructed daylight conditions. More expensive thermopile pyranometers are required for use as calibration standards and measurements under light with unique spectral properties (electric lights, under vegetation, in greenhouses and growth chambers). Routine cleaning, leveling, and annual calibration checks will help to ensure the integrity of long-term data.
Advanced Lighting Controls for Reducing Energy use and Cost in DoD Installations
2013-05-01
OccuSwitch Wireless is a room-based lighting control system employing dimmable light sources, occupancy and daylight sensors , wireless interconnection...combination of wireless and wired control solution for building-wide networked system that maximizes the use of daylight while improving visual...architecture of Hybrid ILDC. Architecture: The system features wireless connectivity among sensors and actuators within a zone and exploits wired
Aging influence on sensing properties of porous silica films sensitized toward ammonia
NASA Astrophysics Data System (ADS)
Tyszkiewicz, Cuma; Rogoziński, Roman
2015-12-01
The sol-gel technology allows preparation of thin silica films ranging in porosity from dense to highly porous. These films can function as a matrix binding molecules of the pH-sensitive dyes and can be utilized as the sensitive films for intensity based planar evanescent wave chemical sensors. Sensitive properties of these dyes decreases in time due to aging processes. We report characterization of weakening of sensing properties of highly porous silica films doped with the bromocresole purple (BCP). In the presence of the gaseous ammonia, the absorption band (AB) of protonated BCP centered at λ=430 nm, is shifted toward λ=591 nm due to deprotonation, resulting in the increase of sensitive films absorption in the range of wavelengths of shifted AB. Two sets of films were investigated. Films from the first one were cyclically exposed to the ammonia and stored isolated from the daylight. Films from the second set weren't exposed to the ammonia and were stored in a staining jar exposed to the daylight. A depth of the AB at λ=430 nm was measured using a spectrophotometer. A sensitivity of the films toward ammonia was measured using LED emitting at center wavelength λ=610 nm. As was shown, the sensitivity of these films exposed to the ammonia diluted in dry air, and isolated from the daylight, decreases in time exponentially. The magnitude of that decrease monotonically depends on the ammonia concentration. It was also shown that the daylight causes quick aging of films not exposed to the ammonia. A depth of the AB centered at λ=430 nm relatively quickly decreased when compared with films isolated from the daylight and exposed to the ammonia.
Hatamleh, Muhanad M; Watts, David C
2010-07-01
The purpose of this study was to test the effect of different periods of accelerated artificial daylight aging on bond strength of glass fiber bundles embedded into maxillofacial silicone elastomer and on bending strength of the glass fiber bundles. Forty specimens were fabricated by embedding resin-impregnated fiber bundles (1.5-mm diameter, 20-mm long) into maxillofacial silicone elastomer. Specimens were randomly allocated into four groups, and each group was subjected to different periods of accelerated daylight aging as follows (in hours); 0, 200, 400, and 600. The aging cycle included continuous exposure to quartz-filtered visible daylight (irradiance 760 W/m(2)) under an alternating weathering cycle (wet for 18 minutes, dry for 102 minutes). Pull-out tests were performed to evaluate bond strength between fiber bundles and silicone using a universal testing machine at 1 mm/min crosshead speed. Also a three-point bending test was performed to evaluate bending strength of the fiber bundles. One-way ANOVA and Bonferroni post hoc tests were carried out to detect statistical significance (p < 0.05). Mean (SD) values of maximum pull-out forces (in N) for groups 1 to 4 were: 13.63 (7.45), 19.67 (1.37), 13.58 (2.61), and 10.37 (2.52). Group 2 exhibited the highest pull-out force that was statistically significant when compared to the other groups. Maximum bending strengths of fiber bundles were in the range of 917.72 MPa to 1124.06 MPa. Bending strength significantly increased after 200 and 400 hours of aging only. After 200 hours of exposure to artificial daylight and moisture conditions, bond strength between glass fibers and heat-cured silicones is optimal, and the bending strength of the glass fiber bundles is enhanced.
Daylighting and shuttering: RIB system mechanical design and preliminary performance data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kinney, L.; Reynolds, D.
1983-12-01
The Reflective, Insulating Blind (RIB) system is a flexible, user-controlled daylighting device which also has direct thermal advantages: it can reject a considerable portion of summer sun while still retaining an adequate daylighting function; and it functions as moveable insulation to significantly decrease thermal losses through fenestration during evening hours. The conceptual design of the RIB system was accomplished by Barnes and Shapira at the Oak Ridge National Laboratory (ORNL). Mechanical design and prototype fabrication was accomplished by the authors and 29 systems were installed immediately inside existing south-facing windows of an energy-efficient office and dormitory at ORNL. The buildingmore » is a heavily-instrumented, passively-solar-heated structure for which reliable performance data was gathered and analyzed before the addition of RIB systems, thus facilitating the interpretation of ''after RIB'' performance data.« less
NASA Astrophysics Data System (ADS)
Galvis, D.; Exposito, C.; Osma, G.; Amado, L.; Ordóñez, G.
2016-07-01
This paper presents an analysis of hybrid lighting systems of Electrical Engineering Building in the Industrial University of Santander, which is a pilot of green building for warm- tropical conditions. Analysis of lighting performance of inner spaces is based on lighting curves obtained from characterization of daylighting systems of these spaces. A computation tool was made in Excel-Visual Basic to simulate the behaviour of artificial lighting system considering artificial control system, user behaviour and solar condition. Also, this tool allows to estimate the electrical energy consumption of the lighting system for a day, a month and a year.
NREL's OpenStudio Helps Design More Efficient Buildings (Fact Sheet)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
2014-07-01
The National Renewable Energy Laboratory (NREL) has created the OpenStudio software platform that makes it easier for architects and engineers to evaluate building energy efficiency measures throughout the design process. OpenStudio makes energy modeling more accessible and affordable, helping professionals to design structures with lower utility bills and less carbon emissions, resulting in a healthier environment. OpenStudio includes a user-friendly application suite that makes the U.S. Department of Energy's EnergyPlus and Radiance simulation engines easier to use for whole building energy and daylighting performance analysis. OpenStudio is freely available and runs on Windows, Mac, and Linux operating systems.
Review of Radio Frequency Photonics Basics
2017-09-06
essentially from “Direct Current to Daylight,” allowing use for high frequency applications. This report covers some needs and advantages of radio...operate essentially from “Direct Current (DC) to Daylight,” allowing use for high frequency applications. The following sections of this report cover...spectrum leaving higher frequencies open for new uses. Frequency bands from 600 MHz to 5 GHz are used for commercial communications in the US. The future
A tuneable approach to uniform light distribution for artificial daylight photodynamic therapy.
O'Mahoney, Paul; Haigh, Neil; Wood, Kenny; Brown, C Tom A; Ibbotson, Sally; Eadie, Ewan
2018-06-16
Implementation of daylight photodynamic therapy (dPDT) is somewhat limited by variable weather conditions. Light sources have been employed to provide artificial dPDT indoors, with low irradiances and longer treatment times. Uniform light distribution across the target area is key to ensuring effective treatment, particularly for large areas. A novel light source is developed with tuneable direction of light emission in order to meet this challenge. Wavelength composition of the novel light source is controlled such that the protoporphyrin-IX (PpIX) weighed spectra of both the light source and daylight match. The uniformity of the light source is characterised on a flat surface, a model head and a model leg. For context, a typical conventional PDT light source is also characterised. Additionally, the wavelength uniformity across the treatment site is characterised. The PpIX-weighted spectrum of the novel light source matches with PpIX-weighted daylight spectrum, with irradiance values within the bounds for effective dPDT. By tuning the direction of light emission, improvements are seen in the uniformity across large anatomical surfaces. Wavelength uniformity is discussed. We have developed a light source that addresses the challenges in uniform, multiwavelength light distribution for large area artificial dPDT across curved anatomical surfaces. Copyright © 2018. Published by Elsevier B.V.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Allen, T.
1997-12-31
As part of the ACT{sup 2} project, sponsored by a major northern California utility, two occupied single-story commercial buildings were equipped with similar yet different daylighting systems in an effort to reduce electric lighting loads and provide a better workspace. The daylighting system, at the newly constructed 15,000 sq.ft. California State Automobile Association (CSAA) office building in Antioch, California, incorporates skylights with louvers, perforated blinds on the windows, and dimming ballasts which control T8 fluorescent fixtures. At the 7,500 sq.ft. retrofitted Verifone office building in Auburn, California, the building required a different kind of skylight to provide daylighting. Die tomore » the 10 foot attic space on the single-story building, a tubular-type of skylight was installed. The tubular skylight incorporates a long cylinder with a reflective internal surface to direct available sunlight into the workspace through a white diffuser. In addition, T8 fluorescent fixtures were controlled by dimming ballasts and light level controls. Annual lighting energy consumption at the CSAA building was reduced by 32% with a favorable reaction from the occupants. While the occupant response to the lighting at Verifone was generally good, thee were some problems in calibrating the lighting controls, thereby reducing energy savings.« less
Circadian occurrence of variceal bleeding in patients with liver cirrhosis.
Siringo, S; Bolondi, L; Sofia, S; Hermida, R C; Gramantieri, L; Gaiani, S; Piscaglia, F; Carbone, C; Misitano, B; Corinaldesi, R
1996-12-01
Several clinical events have a rhythmicity over the 24 h period. We assessed the presence of periodic rhythm in the occurrence of haematemesis in patients with liver cirrhosis under different daylight regimens, namely during standard time and during daylight savings. Over a 48 month period there were 212 consecutive admissions of 118 cirrhotics with variceal bleeding. Complete data were available for 181 episodes of bleeding: 121 (66.9%) started with haematemesis and 60 (33.1%) started with melaena. One hundred and two (56%) episodes occurred during daylight savings and 79 (44%) occurred during standard time. The cosinor test showed a 24 h biphasic peak for the occurrence of haematemesis (09.45 and 21.45 h). Moreover, a biphasic diurnal asymmetric frequency was also found by multiple component rhythmometry. The time peaks of onset of variceal haemorrhage did not change significantly during standard time and daylight savings. Patients with more than one haematemesis episode significantly bled over the same time interval. The present study confirms that over the 24 h period variceal bleeding in cirrhotic patients occurs with a predictable rhythmicity that does not seem to be under the control of the light-dark cycle. The finding of a chronorisk for variceal haemorrhage addresses specific questions for pathophysiological studies as well as for new treatment strategies.
Fathy, Ghada; Asaad, Marwa Kamal; Rasheed, Haval Mohamad
2017-07-01
Conventional photodynamic therapy is associated with inconveniently long clinic visits and discomfort during therapy. Daylight-photodynamic therapy (DL-PDT) is an effective treatment, nearly pain free and more convenient for both the clinics and patients. There are no published studies of methylene blue (MB) as a photosensitizer (PS) used in DL-PDT. Forty patients had multiple plane warts; 20 patients were subjected to DL-PDT with topical 10% methylene blue gel, and 20 patients were subjected to DL-PDT with hematoxylin (placebo). Improvement was evaluated by change of the number of warts and the dermoscope picture. A total of 20 (100%) patients in group II showed no response to placebo, 13 patients (65%) in group I showed complete clearance, 2 (10%) patients showed a good response, and 5 (25%) patients had poor response to treatment (P < 0.01). No serious side effects and patients tolerated the pain well. No relapse was detected during the follow-up period (12 months). Daylight exposure was not monitored with a dosimeter. Daylight-PDT using MB is safe, easy to carry out, economic, effective, acceptable cosmetic results with no recurrence, convenient especially for children and nearly painless treatment. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Design and testing of a mesocosm-scale habitat for culturing the endangered Devils Hole Pupfish
Feuerbacher, Olin; Bonar, Scott A.; Barrett, Paul J.
2016-01-01
aptive propagation of desert spring fishes, whether for conservation or research, is often difficult, given the unique and often challenging environments these fish utilize in nature. High temperatures, low dissolved oxygen, minimal water flow, and highly variable lighting are some conditions a researcher might need to recreate to simulate their natural environments. Here we describe a mesocosm-scale habitat created to maintain hybrid Devils Hole × Ash Meadows Amargosa Pupfish (Cyprinodon diabolis × C. nevadensis mionectes) under conditions similar to those found in Devils Hole, Nevada. This 13,000-L system utilized flow control and natural processes to maintain these conditions rather than utilizing complex and expensive automation. We designed a rotating solar collector to control natural sunlight, a biological reactor to consume oxygen while buffering water quality, and a reverse-daylight photosynthesis sump system to stabilize nighttime pH and swings in dissolved oxygen levels. This system successfully controlled many desired parameters and helped inform development of a larger, more permanent desert fish conservation facility at the U.S. Fish and Wildlife Service’s Ash Meadows National Wildlife Refuge, Nevada. For others who need to raise fish from unique habitats, many components of the scalable and modular design of this system can be adapted at reasonable cost.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Eleanor S.; Thanachareonkit, Anothai; Touzani, Samir
The objective of this monitored field study was to identify near-term innovative façade technologies for solar control and daylighting with a goal of 20-40% energy use savings below Title 24 2013 in the 30-ft deep perimeter zone near vertical windows within cost and comfort constraints. The targeted market was new or existing commercial office buildings or buildings with similar patterns of use.
NASA Technical Reports Server (NTRS)
Monk, T. H.; Buysse, D. J.; Billy, B. D.; Kennedy, K. S.; Kupfer, D. J.
1997-01-01
As part of a larger bedrest study involving various life science experiments, a study was conducted on the effects of 17 days of continuous bedrest and elimination of daylight on circadian rectal temperature rhythms, mood, alertness, and sleep (objective and diary) in eight healthy middle-aged men. Sleep was timed from 2300 to 0700 hours throughout. Three 72-hour measurement blocks were compared: ambulatory prebedrest, early bedrest (days 5-7), and late bedrest (days 15-17). Temperature rhythms showed reduced amplitude and later phases resulting from the bedrest conditions. This was associated with longer nocturnal sleep onset latencies and poorer subjectively rated sleep but with no reliable changes in any of the other sleep parameters. Daily changes in posture and/or exposure to daylight appear to be important determinants of a properly entrained circadian system.
Daylighting performance and thermal implications of skylights vs. south-facing roof monitors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rosenbaum, M.; Coldham, B.
1997-12-31
This paper reports the results of a comparison of skylights vs. south-facing roof monitors for daylighting the north wall zone of a 10,000 ft{sup 2} office building near Manchester, NH. A physical model was constructed and tested. Simultaneously, the building`s annual thermal performance was modeled with Energy-10 hourly simulation software, and its peak heating and cooling load performance was modeled with the Carrier Corp. Hourly Analysis Program (HAP). Apertures were built into the roof of the model, and several skylight and south-facing roof monitor configurations were tested in both clear and overcast conditions. A design goal was to have themore » building be daylit on overcast as well as clear days. This goal was based more on enhancement of the working environment than it was on electrical energy savings. Monitors with overhangs performed poorly in the overcast conditions--it was determined that 2.4 times as much monitor aperture was needed to yield equivalent light levels in overcast conditions. The thermal models showed that the annual heating and cooling energy cost for the building was the same for either strategy, but that peak cooling loads and peak heating loads were lower with the skylit version. The authors concluded that skylights were preferred over monitors in this application, due to similar annual energy costs, lower peak loads, and lower construction cost.« less
Photoluminescence properties of white light emitting La2O3:Dy3+ nanocrystals
NASA Astrophysics Data System (ADS)
Reenabati Devi, Konsam; Dorendrajit Singh, Shougaijam; David Singh, Th.
2018-06-01
White light emitting nanocrystalline La2O3:Dy3+ phosphors with different concentration (0.5-2 at.%) were synthesized by simple precipitation method. X-ray diffraction (XRD) pattern indicates all the samples crystallizes in the hexagonal phase. Average crystallite sizes of the samples calculated from XRD data were found to be in the range of 20-55 nm. Transmission electron microscopy, selected area electron diffraction, energy dispersive analysis of X-ray and photoluminescence (PL) of the samples are also reported. Strong PL excitation peak due to charge transfer band was observed at 230 nm. Photoluminescence emission peaks observed at 486 and 575 nm were probably attributed to 4F9/2-6H15/2 and 4F9/2-6H13/2 of Dy3+ ions respectively. Optimum luminescence intensity is found at 1 at.% Dy3+ doped La2O3 sample. Further, Commission Internationale de l'é clairage (CIE, 1931) co-ordinates and correlated color temperature (CCT) of the doped sample were calculated to investigate the phosphors' performance and technical applicability of the emitted light respectively. CCT of the 0.5 and 1 at.% samples is 5894 K (white light), within the range of vertical daylight, which makes the synthesised samples promising nanophosphor and may find application in simulating vertical daylight of the Sun.
Photoluminescence properties of white light emitting La2O3:Dy3+ nanocrystals
NASA Astrophysics Data System (ADS)
Reenabati Devi, Konsam; Dorendrajit Singh, Shougaijam; David Singh, Th.
2018-01-01
White light emitting nanocrystalline La2O3:Dy3+ phosphors with different concentration (0.5-2 at.%) were synthesized by simple precipitation method. X-ray diffraction (XRD) pattern indicates all the samples crystallizes in the hexagonal phase. Average crystallite sizes of the samples calculated from XRD data were found to be in the range of 20-55 nm. Transmission electron microscopy, selected area electron diffraction, energy dispersive analysis of X-ray and photoluminescence (PL) of the samples are also reported. Strong PL excitation peak due to charge transfer band was observed at 230 nm. Photoluminescence emission peaks observed at 486 and 575 nm were probably attributed to 4F9/2-6H15/2 and 4F9/2-6H13/2 of Dy3+ ions respectively. Optimum luminescence intensity is found at 1 at.% Dy3+ doped La2O3 sample. Further, Commission Internationale de l'é clairage (CIE, 1931) co-ordinates and correlated color temperature (CCT) of the doped sample were calculated to investigate the phosphors' performance and technical applicability of the emitted light respectively. CCT of the 0.5 and 1 at.% samples is 5894 K (white light), within the range of vertical daylight, which makes the synthesised samples promising nanophosphor and may find application in simulating vertical daylight of the Sun.
Perception and eye movements in simulated traffic situations.
Luoma, J
1984-01-01
In an experiment to simulate the perception task of a driver, subjects were shown uninterrupted series of colour slides of different kinds of highway scenes. The dependent variables were eye fixations, fixation times and conscious perceptions for the part of the traffic signs and roadside advertisements. Perceptions were achieved mostly as a result of fixation, but partly also by using peripheral vision. On the other hand fixation did not always cause perception. The lengthening of fixation time increased the number of correct perceptions. When the traffic sign and the roadside advertisement were in the same slide, the advertisement disturbed the perception of the sign, but in the daylight conditions this effect was not noticed as an alteration of the fixation of the sign, but as prevention of further information processing. The disturbing influence of the advertisement was increased by its bad information ergonomics which caused a long fixation time.
Sanders, William J.; Snyder, Marvin K.; Harter, James W.
1983-01-01
The amount of building heating, cooling and daylighting is controlled by at least one pair of solar energy passing panels, with each panel of the pair of panels being exposed to a separate direction of sun incidence. A shutter-shade combination is associated with each pair of panels and the shutter is connected to the shade so that rectilinear movement of the shutter causes pivotal movement of the shade.
Chemical reactions in perfume ageing.
Blakeway, J M; Frey, M L; Lacroix, S; Salerno, M S
1987-10-01
Summary The interactions between a typical range of perfume materials, alcohol, water, air, elevated temperatures and daylight have been studied. The changes of composition, acidity, peroxide content and the formation of new molecules were followed. The stabilizing effects of UV absorbers, antioxidants and sequestering agents were examined; - the formation of acid reaction products was accelerated by air, temperature, daylight and the presence of natural products; - peroxide formation was accelerated by heat and light and the presence of air; as the acidity increased, the peroxides decomposed; - the acetalization of other aldehydes was accelerated by temperature and daylight and the presence of natural products up to 40% of certain aldehydes may be converted into acetals after 3 months at 37 degrees C; - many stereoisomerizations occur, e.g., transisoeugenol is converted up to 10% into the cis isomer after 3 months at 37 degrees C and 58% in daylight; - evaluation of antioxidants UV absorbers and sequestering agents showed a significant protection against deterioration only by EDTA dipotassium salt; - ethanol was converted into acetaldehyde and its diethylacetal by peroxides present and formed on ageing up to 0.08%. Natural products accelerated this formation; - the reaction between benzoyl peroxide and ethanol was shown to yield up to 63% of acetaldehyde+diethyl acetal whilst di-t-butyl peroxide gave only 23% under the same conditions. These results go some way to explaining odour changes in perfume ageing.
NASA Technical Reports Server (NTRS)
Dugan, Daniel C.; Delamer, Kevin J.
2005-01-01
Because of increasing accident rates in Army helicopters in hover and low speed flight, a study was made in 1999 of accidents which could be attributed to inadequate stability augmentation. A study of civil helicopter accidents from 1993-2004 was then undertaken to pursue the issue of poor handling qualities in helicopters which, in almost all cases, had no stability augmentation. The vast majority of the mishaps studied occurred during daylight in visual meteorological condition, reducing the impact of degraded visual environments (DVE) on the results. Based on the Cooper-Harper Rating Scale, the handling qualities of many of the helicopters studied could be described as having from "very objectionable" to "major" deficiencies. These costly deficiencies have resulted in unnecessary loss of life, injury, and high dollar damage. Low cost and lightweight augmentation systems for helicopters have been developed in the past and are still being investigated. They offer the potential for significant reductions in the accident rate.
Super Resolution Algorithm for CCTVs
NASA Astrophysics Data System (ADS)
Gohshi, Seiichi
2015-03-01
Recently, security cameras and CCTV systems have become an important part of our daily lives. The rising demand for such systems has created business opportunities in this field, especially in big cities. Analogue CCTV systems are being replaced by digital systems, and HDTV CCTV has become quite common. HDTV CCTV can achieve images with high contrast and decent quality if they are clicked in daylight. However, the quality of an image clicked at night does not always have sufficient contrast and resolution because of poor lighting conditions. CCTV systems depend on infrared light at night to compensate for insufficient lighting conditions, thereby producing monochrome images and videos. However, these images and videos do not have high contrast and are blurred. We propose a nonlinear signal processing technique that significantly improves visual and image qualities (contrast and resolution) of low-contrast infrared images. The proposed method enables the use of infrared cameras for various purposes such as night shot and poor lighting environments under poor lighting conditions.
Trivedi, Amit K; Rani, Sangeeta; Kumar, Vinod
2006-01-01
Background A stable and systematic daily change in light levels at dawn and dusk provides the most reliable indicator of the phase of the day. It is likely that organisms have evolved mechanisms to use these twilight transitions as the primary zeitgeber to adjust their circadian phases. In this study, we investigated under natural illumination conditions the effects of daylight exposure restricted to twilights on the timing of testicular regression and locomotor activity of the house sparrow (Passer domesticus), which possesses a strongly self-sustaining circadian system. Methods and results Two experiments were performed on adult male house sparrows. Beginning in the third week of April, the first experiment examined whether exposure to natural daylight only during twilights influenced the timing of testicular regression and concomitant changes in testosterone-dependent beak color of reproductively mature sparrows. Interestingly, there was a significant delay in testicular regression and depigmentation of the beak in sparrows exposed to natural daylight (NDL) only during twilights as compared to those exposed to NDL all day. The second experiment examined twice in the year, around the equinoxes (March and September), the effects of exposure to twilights only on the daily activity rhythm of sparrows kept in an outdoor aviary. Five of 7 birds continued exhibiting entrained activity rhythms when exposed only to twilights (NDL minus day light from sunrise to sunset) in September, but not in March. Both in NDL and twilight conditions, March birds had significantly lower activity counts than September birds. Conclusion Exposure to natural daylight only during twilights delayed the timing of testicular regression and concomitant depigmentation of the beak but did not affect the daily activity rhythm in male sparrows. This suggests that daily twilights can serve as cues for regulation of the circadian activity rhythm but not for the photoperiodic regulation of testicular cycle in the house sparrow. PMID:16553964
How daylight influences high-order chromatic descriptors in natural images.
Ojeda, Juan; Nieves, Juan Luis; Romero, Javier
2017-07-01
Despite the global and local daylight changes naturally occurring in natural scenes, the human visual system usually adapts quite well to those changes, developing a stable color perception. Nevertheless, the influence of daylight in modeling natural image statistics is not fully understood and has received little attention. The aim of this work was to analyze the influence of daylight changes in different high-order chromatic descriptors (i.e., color volume, color gamut, and number of discernible colors) derived from 350 color images, which were rendered under 108 natural illuminants with Correlated Color Temperatures (CCT) from 2735 to 25,889 K. Results suggest that chromatic and luminance information is almost constant and does not depend on the CCT of the illuminant for values above 14,000 K. Nevertheless, differences between the red-green and blue-yellow image components were found below that CCT, with most of the statistical descriptors analyzed showing local extremes in the range 2950 K-6300 K. Uniform regions and areas of the images attracting observers' attention were also considered in this analysis and were characterized by their patchiness index and their saliency maps. Meanwhile, the results of the patchiness index do not show a clear dependence on CCT, and it is remarkable that a significant reduction in the number of discernible colors (58% on average) was found when the images were masked with their corresponding saliency maps. Our results suggest that chromatic diversity, as defined in terms of the discernible colors, can be strongly reduced when an observer scans a natural scene. These findings support the idea that a reduction in the number of discernible colors will guide visual saliency and attention. Whatever the modeling is mediating the neural representation of natural images, natural image statistics, it is clear that natural image statistics should take into account those local maxima and minima depending on the daylight illumination and the reduction of the number of discernible colors when salient regions are considered.
Effects of weather conditions, light conditions, and road lighting on vehicle speed.
Jägerbrand, Annika K; Sjöbergh, Jonas
2016-01-01
Light conditions are known to affect the number of vehicle accidents and fatalities but the relationship between light conditions and vehicle speed is not fully understood. This study examined whether vehicle speed on roads is higher in daylight and under road lighting than in darkness, and determined the combined effects of light conditions, posted speed limit and weather conditions on driving speed. The vehicle speed of passenger cars in different light conditions (daylight, twilight, darkness, artificial light) and different weather conditions (clear weather, rain, snow) was determined using traffic and weather data collected on an hourly basis for approximately 2 years (1 September 2012-31 May 2014) at 25 locations in Sweden (17 with road lighting and eight without). In total, the data included almost 60 million vehicle passes. The data were cleaned by removing June, July, and August, which have different traffic patterns than the rest of the year. Only data from the periods 10:00 A.M.-04:00 P.M. and 06:00 P.M.-10:00 P.M. were used, to remove traffic during rush hour and at night. Multivariate adaptive regression splines was used to evaluate the overall influence of independent variables on vehicle speed and nonparametric statistical testing was applied to test for speed differences between dark-daylight, dark-twilight, and twilight-daylight, on roads with and without road lighting. The results show that vehicle speed in general depends on several independent variables. Analyses of vehicle speed and speed differences between daylight, twilight and darkness, with and without road lighting, did not reveal any differences attributable to light conditions. However, vehicle speed decreased due to rain or snow and the decrease was higher on roads without road lighting than on roads with lighting. These results suggest that the strong association between traffic accidents and darkness or low light conditions could be explained by drivers failing to adjust their speed to the reduced visibility in dark conditions.
Optical characterization of fritted glass for architectural applications
NASA Astrophysics Data System (ADS)
Jonsson, Jacob C.; Rubin, Michael D.; Nilsson, Annica M.; Jonsson, Andreas; Roos, Arne
2009-04-01
Fritted glass is commonly used as a light diffusing element in modern buildings. Traditionally it has been used for aesthetic purposes but it can also be used for energy savings by incorporating it in novel daylighting systems? To answer such questions the light scattering properties must be properly characterized. This paper contains measurements of different varieties of fritted glass, ranging from the simplest direct-hemispherical measurements to angle-resolved goniometer measurements. Modeling the light scattering to obtain the full bidirectional scattering distribution function (BSDF) extends the measured data, making it useful in simulation programs such as Window 6 and Radiance. Surface profilometry results and SEM micrographs are included to demonstrate the surface properties of the samples studied.
Flight directions of passerine migrants in daylight and darkness: A radar and direct visual study
NASA Technical Reports Server (NTRS)
Gauthreaux, S. A., Jr.
1972-01-01
The application of radar and visual techniques to determine the migratory habits of passerine birds during daylight and darkness is discussed. The effects of wind on the direction of migration are examined. Scatter diagrams of daytime and nocturnal migration track directions correlated with wind direction are presented. It is concluded that migratory birds will fly at altitudes where wind direction and migratory direction are nearly the same. The effects of cloud cover and solar obscuration are considered negligible.
The Taranaki daylight fireball, 1999 July 7
NASA Astrophysics Data System (ADS)
McCormick, Jennie
2006-10-01
The New Zealand Taranaki Daylight Fireball was observed on 1999 July 7 from various areas across the North and South Islands of New Zealand and had an apparent magnitude brighter than -20. The event produced more than one hundred handwritten reports, drawings, and paintings from eyewitnesses; video and audio recordings, seismic trace data, and confirmation of detection by the United States Defense Department satellites. A detailed case study based on this data shows that observations by the public are invaluable when compiling a formal history of such events.
2006-01-01
Systems, Thermal Comfort 1 Credit 3 Enhanced Commissioning 1 Credit 7.1 Thermal Comfort , Compliance 1 Credit 4 Enhanced Refrigerant Management 1 Credit 7.2... Thermal Comfort , Validation ? Credit 5 Measurement & Verification 1 Credit 8.1 Daylight & Views, Daylight 75% of Spaces 1 Credit 6 Green Power N...Systems, Thermal Comfort 1 Credit 3 Enhanced Commissioning 1 Credit 7.1 Thermal Comfort , Compliance 1 Credit 4 Enhanced Refrigerant Management 1 Credit 7.2
Daylight time-resolved photographs of lightning.
Qrville, R E; Lala, G G; Idone, V P
1978-07-07
Lightning dart leaders and return strokes have been recorded in daylight with both good spatial resolution and good time resolution as part of the Thunder-storm Research International Program. The resulting time-resolved photographs are apparently equivalent to the best data obtained earlier only at night. Average two-dimensional return stroke velocities in four subsequent strokes between the ground and a height of 1400 meters were approximately 1.3 x 10(8) meters per second. The estimated systematic error is 10 to 15 percent.
Does Daylight Savings Time encourage physical activity?
Zick, Cathleen D
2014-07-01
Extending Daylight Savings Time (DST) has been identified as a policy intervention that may encourage physical activity. However, there has been little research on the question of if DST encourages adults to be more physically active. Data from residents of Arizona, Colorado, New Mexico, and Utah ages 18-64 who participated in the 2003-2009 American Time Use Survey are used to assess whether DST is associated with increased time spent in moderate-to-vigorous physical activity (MVPA). The analysis capitalizes on the natural experiment created because Arizona does not observe DST. Both bivariate and multivariate analyses indicate that shifting 1 hour of daylight from morning to evening does not impact MVPA of Americans living in the southwest. While DST may affect the choices people make about the timing and location of their sports/recreational activities, the potential for DST to serve as a broad-based intervention that encourages greater sports/recreation participation is not supported by this analysis. Whether this null effect would persist in other climate situations is an open question.
Daylight photodynamic therapy with methyl-aminolevulinate for the treatment of actinic cheilitis.
Fai, Dario; Romanello, Eugenio; Brumana, Marta Benedetta; Fai, Carlotta; Vena, Gino Antonio; Cassano, Nicoletta; Piaserico, Stefano
2015-01-01
Actinic cheilitis (AC) is a common premalignant condition that requires an effective treatment to reduce the risk of malignant transformation. Photodynamic therapy (PDT) has been recently added to the armamentarium available for AC treatment. Daylight PDT (D-PDT) is a novel PDT modality in which the activation of the topical photosensitizer is induced by the exposure to natural daylight instead of artificial light sources without preliminary occlusion. This simplified procedure was found to be more tolerated as compared to conventional PDT. We report our preliminary experience on the use of D-PDT using methyl-aminolevulinate cream in 10 patients with refractory AC of the lower lip. Patients received two consecutive D-PDT sessions with an interval of 7-14 days. At 3 months after therapy, a complete response was observed in seven patients, with sustained results in five patients over an observational period of 6-12 months. Treatment was well tolerated. © 2015 Wiley Periodicals, Inc.
Detecting aircraft with a low-resolution infrared sensor.
Jakubowicz, Jérémie; Lefebvre, Sidonie; Maire, Florian; Moulines, Eric
2012-06-01
Existing computer simulations of aircraft infrared signature (IRS) do not account for dispersion induced by uncertainty on input data, such as aircraft aspect angles and meteorological conditions. As a result, they are of little use to estimate the detection performance of IR optronic systems; in this case, the scenario encompasses a lot of possible situations that must be indeed addressed, but cannot be singly simulated. In this paper, we focus on low-resolution infrared sensors and we propose a methodological approach for predicting simulated IRS dispersion of poorly known aircraft and performing aircraft detection on the resulting set of low-resolution infrared images. It is based on a sensitivity analysis, which identifies inputs that have negligible influence on the computed IRS and can be set at a constant value, on a quasi-Monte Carlo survey of the code output dispersion, and on a new detection test taking advantage of level sets estimation. This method is illustrated in a typical scenario, i.e., a daylight air-to-ground full-frontal attack by a generic combat aircraft flying at low altitude, over a database of 90,000 simulated aircraft images. Assuming a white noise or a fractional Brownian background model, detection performances are very promising.
2013-01-01
Background A considerable percentage of flight crew reports to be fatigued regularly. This is partly caused by irregular and long working hours and the crossing of time zones. It has been shown that persistent fatigue can lead to health problems, impaired performance during work, and a decreased work-private life balance. It is hypothesized that an intervention consisting of tailored advice regarding exposure to daylight, optimising sleep, physical activity, and nutrition will lead to a reduction of fatigue in airline pilots compared to a control group, which receives a minimal intervention with standard available information. Methods/design The study population will consist of pilots of a large airline company. All pilots who posses a smartphone or tablet, and who are not on sick leave for more than four weeks at the moment of recruitment, will be eligible for participation. In a two-armed randomised controlled trial, participants will be allocated to an intervention group that will receive the tailored advice to optimise exposure to daylight, sleep, physical activity and nutrition, and a control group that will receive standard available information. The intervention will be applied using a smartphone application and a website, and will be tailored on flight- and participant-specific characteristics. The primary outcome of the study is perceived fatigue. Secondary outcomes are need for recovery, duration and quality of sleep, dietary and physical activity behaviours, work-private life balance, general health, and sickness absence. A process evaluation will be conducted as well. Outcomes will be measured at baseline and at three and six months after baseline. Discussion This paper describes the development of an intervention for airline pilots, consisting of tailored advice (on exposure to daylight and sleep-, physical activity, and nutrition) applied into a smartphone application. Further, the paper describes the design of the randomised controlled trial evaluating the effect of the intervention on fatigue, health and sickness absence. If proven effective, the intervention can be applied as a new and practical tool in fatigue management. Results are expected at the end of 2013. Trial registration Netherlands Trial Register: NTR2722 PMID:23971514
van Drongelen, Alwin; van der Beek, Allard J; Hlobil, Hynek; Smid, Tjabe; Boot, Cécile R L
2013-08-26
A considerable percentage of flight crew reports to be fatigued regularly. This is partly caused by irregular and long working hours and the crossing of time zones. It has been shown that persistent fatigue can lead to health problems, impaired performance during work, and a decreased work-private life balance. It is hypothesized that an intervention consisting of tailored advice regarding exposure to daylight, optimising sleep, physical activity, and nutrition will lead to a reduction of fatigue in airline pilots compared to a control group, which receives a minimal intervention with standard available information. The study population will consist of pilots of a large airline company. All pilots who posses a smartphone or tablet, and who are not on sick leave for more than four weeks at the moment of recruitment, will be eligible for participation.In a two-armed randomised controlled trial, participants will be allocated to an intervention group that will receive the tailored advice to optimise exposure to daylight, sleep, physical activity and nutrition, and a control group that will receive standard available information. The intervention will be applied using a smartphone application and a website, and will be tailored on flight- and participant-specific characteristics. The primary outcome of the study is perceived fatigue. Secondary outcomes are need for recovery, duration and quality of sleep, dietary and physical activity behaviours, work-private life balance, general health, and sickness absence. A process evaluation will be conducted as well. Outcomes will be measured at baseline and at three and six months after baseline. This paper describes the development of an intervention for airline pilots, consisting of tailored advice (on exposure to daylight and sleep-, physical activity, and nutrition) applied into a smartphone application. Further, the paper describes the design of the randomised controlled trial evaluating the effect of the intervention on fatigue, health and sickness absence. If proven effective, the intervention can be applied as a new and practical tool in fatigue management. Results are expected at the end of 2013. Netherlands Trial Register: NTR2722.
Flash/crazing effects on simulator pursuit tracking performance
NASA Astrophysics Data System (ADS)
Stamper, D. A.; Lund, D. J.; Levine, R. R.; Molchany, J. W.; Best, P.
1986-03-01
Day sights which are purposefully or inadvertently irradiated with laser radiation may become nonfunctional due to cracking or crazing of the optical glass. The degree of performance degradation may be related to the amount of damage to the glass and possible flash blindness from reradiation. Thirty-two male enlisted men and officers tracked a scale model tank through a constant arc at a simulated distance of 1 km, using a laboratory constructed viscous-damped tracking device. There were four crazing groups (4 men/group) under bright and dim ambient light conditions for a total of eight groups. Each man tracked the target during three flash/crazing and three crazing only trials, which were randomly presented during 30 trials. The simulated countermeasure which included the flash and crazing had dramatic effects on tracking performance, even under daylight conditions. Under the most severe degree of crazing, tracking performance was not possible under either ambient light condition. The relatively small amounts of laser radiation used to craze the BK-7 glass used in this study, which lead to significant performance decrements, demonstrates the potential impact of flash/crazing effects on operators of day sights.
A new method for assessing the risk of accident associated with darkness.
Johansson, Osten; Wanvik, Per Ole; Elvik, Rune
2009-07-01
This paper presents a new method for assessing the risk of accidents associated with darkness. The method estimates the risk of accident associated with darkness in terms of an odds ratio, which is defined as follows: [(number of accidents in darkness in a given hour of the day)/(number of accidents in daylight in the same hour of the day)]/[(Number of accidents in a given comparison hour when the case hour is dark)/(Number of accidents in a given comparison hour when the case hour is in daylight)]. This estimate of the risk of accident associated with darkness does not require data on exposure, but relies on the count of accidents in the same pair of hours throughout the year. One of the hours is dark part of the year, but has daylight the rest of the year. The comparison hour, which has daylight the whole year, is used to control for seasonal variations. The aim of relying on the same pair of hours throughout the year is to minimise the influence of potentially confounding factors. Estimates of the risk of injury accidents associated with darkness are developed on the basis of accident data for Norway, Sweden and the Netherlands. It is found that the risk of an injury accident increases by nearly 30% in darkness in urban areas, by nearly 50% in rural areas, and by about 40% for urban and rural areas combined (adjusted estimate).
The effect of ambient lighting on Laser Doppler Imaging of a standardized cutaneous injury model.
Pham, Alan Chuong Q; Hei, Erik La; Harvey, John G; Holland, Andrew Ja
2017-01-01
The aim of this study was to investigate the potential confounding effects of four different types of ambient lighting on the results of Laser Doppler Imaging (LDI) of a standardized cutaneous injury model. After applying a mechanical stimulus to the anterior forearm of a healthy volunteer and inducing a wheal and arteriolar flare (the Triple response), we used a Laser Doppler Line Scanner (LDLS) to image the forearm under four different types of ambient lighting: light-emitting-diode (LED), compact fluorescent lighting (CFL), halogen, daylight, and darkness as a control. A spectrometer was used to measure the intensity of light energy at 785 nm, the wavelength used by the scanner for measurement under each type of ambient lighting. Neither the LED nor CFL bulbs emitted detectable light energy at a wavelength of 785 nm. The color-based representation of arbitrary perfusion unit (APU) values of the Triple response measured by the scanner was similar between darkness, LED, and CFL light. Daylight emitted 2 mW at 785 nm, with a slight variation tending more towards lower APU values compared to darkness. Halogen lighting emitted 6 mW of light energy at 785 nm rendering the color-based representation impossible to interpret. Halogen lighting and daylight have the potential to confound results of LDI of cutaneous injuries whereas LED and CFL lighting did not. Any potential sources of daylight should be reduced and halogen lighting completely covered or turned off prior to wound imaging.
The shift to and from daylight savings time and motor vehicle crashes.
Lambe, M; Cummings, P
2000-07-01
The objective of the study was to examine whether the shifts to and from daylight savings time in Sweden have short-term effects on the incidence of traffic crashes. A database maintained by the Swedish National Road Administration was used to examine crashes from 1984 through 1995, that occurred on state roads the Monday preceding, the Monday immediately after (index Monday), and the Monday 1 week after the change to daylight savings time in the spring and for the corresponding three Mondays in the autumn. The Mondays 1 week before and after the time changes were taken as representing the expected incidence of crashes. Crash incidence was calculated per 1000 person-years using population estimates for each year of the study. The association between 1 h of possible sleep loss and crash incidence was estimated by the incidence rate ratio from negative binomial regression. The incidence rate ratio was 1.04 (95% CI, 0.92-1.16) for a Monday on which drivers were expected to have had 1 h less sleep, compared with other Mondays. In the spring, the incidence rate ratio for crashes was 1.11 (95% CI, 0.93-1.31) for Mondays after the time change compared to other spring Mondays. The corresponding rate ratio for the fall was 0.98 (95% CI, 0.84-1.15) It was concluded that the shift to and from daylight savings time did not have measurable important immediate effects on crash incidence in Sweden.
NASA Astrophysics Data System (ADS)
Morita, Shogo; Ito, Shusei; Yamamoto, Hirotsugu
2017-02-01
Aerial display can form transparent floating screen in the mid-air and expected to provide aerial floating signage. We have proposed aerial imaging by retro-reflection (AIRR) to form a large aerial LED screen. However, luminance of aerial image is not sufficiently high so as to be used for signage under broad daylight. The purpose of this paper is to propose a novel aerial display scheme that features hybrid display of two different types of images. Under daylight, signs made of cubes are visible. At night, or under dark lighting situation, aerial LED signs become visible. Our proposed hybrid display is composed of an LED sign, a beam splitter, retro-reflectors, and transparent acrylic cubes. Aerial LED sign is formed with AIRR. Furthermore, we place transparent acrylic cubes on the beam splitter. Light from the LED sign enters transparent acrylic cubes, reflects twice in the transparent acrylic cubes, exit and converge to planesymmetrical position with light source regarding the cube array. Thus, transparent acrylic cubes also form the real image of the source LED sign. Now, we form a sign with the transparent acrylic cubes so that this cube-based sign is apparent under daylight. We have developed a proto-type display by use of 1-cm transparent cubes and retro-reflective sheeting and successfully confirmed aerial image forming with AIRR and transparent cubes as well as cube-based sign under daylight.
A View on Future Building System Modeling and Simulation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wetter, Michael
This chapter presents what a future environment for building system modeling and simulation may look like. As buildings continue to require increased performance and better comfort, their energy and control systems are becoming more integrated and complex. We therefore focus in this chapter on the modeling, simulation and analysis of building energy and control systems. Such systems can be classified as heterogeneous systems because they involve multiple domains, such as thermodynamics, fluid dynamics, heat and mass transfer, electrical systems, control systems and communication systems. Also, they typically involve multiple temporal and spatial scales, and their evolution can be described bymore » coupled differential equations, discrete equations and events. Modeling and simulating such systems requires a higher level of abstraction and modularisation to manage the increased complexity compared to what is used in today's building simulation programs. Therefore, the trend towards more integrated building systems is likely to be a driving force for changing the status quo of today's building simulation programs. Thischapter discusses evolving modeling requirements and outlines a path toward a future environment for modeling and simulation of heterogeneous building systems.A range of topics that would require many additional pages of discussion has been omitted. Examples include computational fluid dynamics for air and particle flow in and around buildings, people movement, daylight simulation, uncertainty propagation and optimisation methods for building design and controls. For different discussions and perspectives on the future of building modeling and simulation, we refer to Sahlin (2000), Augenbroe (2001) and Malkawi and Augenbroe (2004).« less
Effects of skylight parameters on daylighting energy savings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arasteh, D.; Johnson, R.; Selkowitz, S.
1985-05-01
Skylight parameters that affect lighting, cooling, heating, fan, and total energy use in office buildings are examined using the state-of-the-art building energy analysis computer code, DOE-2.1B. The lighting effects of skylight spatial distribution, skylight area, skylight visible transmission, well factor, illumination setpoint, interior partitions, ceiling height, and glazing characteristics are discussed. This study serves as the foundation for the creation of a DOE-2.1B data base and design tools for estimating daylighting energy savings from skylights. 13 refs., 9 figs., 1 tab.
SPiRiT Scoring Through Self-Assessment Charrettes
2004-09-01
Continued) 0 Max 17 5.C5 Indoor Chemical and Pollutant Source Control 1 5.C6 Controllability of Systems 2 5.C7 Thermal Comfort 2 5.C8...Pollutant Source Control 1 5.C6 Controllability of Systems 2 5.C7 Thermal Comfort 2 5.C8 Daylight and Views 2 5.C9 Acoustic Environment...1 5.C6 Controllability of Systems 2 5.C7 Thermal Comfort 2 5.C8 Daylight and Views 2 5.C9 Acoustic Environment /Noise Control 1 5
2009-03-26
annually ( McHugh , et al., 1998). USAF has used daylighting as an energy savings strategy in earlier studies (Holtz, 1990); and is pursuing it to meet...using renewable energy to generate electricity ( McHugh , et al., 1998). For example, traditional utility systems that are straining to meet peak...1998) found that lighting accounts for 40-50% of commercial energy consumption and McHugh , Burns, and Hittle (1998) stated that electric lighting and
NASA Astrophysics Data System (ADS)
Schweitzer, S.; Schinagl, C.; Djuras, G.; Frühwirth, M.; Hoschopf, H.; Wagner, F.; Schulz, B.; Nemitz, W.; Grote, V.; Reidl, S.; Pritz, P.; Moser, M.; Wenzl, F. P.
2016-09-01
In recent years, LED lighting became an indispensable alternative to conventional lighting systems. Sophisticated solutions offer not only comfortable white light with a good color rendering. They also provide the possibility of changing illuminance and color temperature. Some systems even simulate daylight over the entire day, some including natural variations as due to clouds. Such systems are supposed to support the chronobiological needs of human and to have a positive effect on well-being, performance, sleep-quality and health. Lighting can also be used to support specific aims in a situation, like to improve productivity in activation or to support recreation in relaxation. Research regarding suitable light-settings for such situations and superordinate questions like their influence on well-being and health is still incomplete. We investigated the subjective preferences of men and women regarding light-settings for activation and relaxation. We supplied two rooms and four cubes with light sources that provide the possibility of tuning illuminance, color temperature and deviation from Plackian locus. More than 80 individuals - belonging to four groups differing in gender and age - were asked to imagine activating and recovering situations for which they should adjust suitable and pleasant lighting by tuning the above mentioned light properties. It was shown that there are clear differences in the lighting conditions preferred for these two situations. Also some combined gender- and age-specific differences became apparent.
Nickel-cadium batteries for Apollo telescope mount
NASA Technical Reports Server (NTRS)
Kirsch, W. W.; Shikoh, A. E.
1974-01-01
The operational testing and evaluation program is presented which was conducted on 20-ampere-hour nickel-cadmium (Ni-Cd) batteries for use on the Apollo telescope mount (ATM). The test program was initiated in 1967 to determine if the batteries could meet ATM mission requirements and to determine operating characteristics and methods. The ATM system power and charging power for the Ni-Cd secondary batteries is provided by a solar array during the 58-minute daylight portion of the orbit; during the 36-minute night portion of the orbit, the Ni-Cd secondary batteries will supply ATM system power. The test results reflect battery operating characteristics and parameters relative to simulated ATM orbital test conditions. Maximum voltage, charge requirements, capacity, temperature, and cyclic characteristics are presented.
NASA Astrophysics Data System (ADS)
Larionova, Kira; Stetsky, Sergey
2018-03-01
The main rationale and objective of the submitted research work is to create a quality lighting environment in the premises of deepened buildings and below-ground structures under screen effect of high-rise construction (high-rise buildings). It is noted, that in modern megapolises, a deficiency of vacant urban territories leads to the increased density of urban development with increased amount of high-rise construction and tendency to increase efficiency in the use of underground space. The natural lighting of premises in underground buildings and structures is the most efficient way, but it can be implemented only under use of roof lighting system in the form of roof monitors or skylights. In this case the levels of indoor natural lighting will be affected with serious screening effect of high-rise buildings in surrounding development. Such an situation is not regulated, or even considered by the contemporary building Codes and Regulations on natural lighting of interiors. The authors offered a new formula for a daylight factor calculation with roof lighting system in the described cases. The results of theoretical calculations and experimental studies showed very similar values. This proved the truth of the offered formula and elaborated method of calculation on the basis of an offered hypothesis. It prooves, that it is possible to use some factor and guide points in the daylight factors design under system of side natural lighting in the same design for a system of roof lighting.
The effect of ambient lighting on Laser Doppler Imaging of a standardized cutaneous injury model
Pham, Alan Chuong Q; Hei, Erik La; Harvey, John G; Holland, Andrew JA
2017-01-01
Objective: The aim of this study was to investigate the potential confounding effects of four different types of ambient lighting on the results of Laser Doppler Imaging (LDI) of a standardized cutaneous injury model. Methods: After applying a mechanical stimulus to the anterior forearm of a healthy volunteer and inducing a wheal and arteriolar flare (the Triple response), we used a Laser Doppler Line Scanner (LDLS) to image the forearm under four different types of ambient lighting: light-emitting-diode (LED), compact fluorescent lighting (CFL), halogen, daylight, and darkness as a control. A spectrometer was used to measure the intensity of light energy at 785 nm, the wavelength used by the scanner for measurement under each type of ambient lighting. Results: Neither the LED nor CFL bulbs emitted detectable light energy at a wavelength of 785 nm. The color-based representation of arbitrary perfusion unit (APU) values of the Triple response measured by the scanner was similar between darkness, LED, and CFL light. Daylight emitted 2 mW at 785 nm, with a slight variation tending more towards lower APU values compared to darkness. Halogen lighting emitted 6 mW of light energy at 785 nm rendering the color-based representation impossible to interpret. Conclusions: Halogen lighting and daylight have the potential to confound results of LDI of cutaneous injuries whereas LED and CFL lighting did not. Any potential sources of daylight should be reduced and halogen lighting completely covered or turned off prior to wound imaging. PMID:29348978
Hunting influences the diel patterns in habitat selection by northern pintails Anas acuta
Casazza, Michael L.; Coates, Peter S.; Miller, Michael R.; Overton, Cory T.; Yparraguirre, Daniel R.
2012-01-01
Northern pintail Anas acuta (hereafter pintail) populations wintering within Suisun Marsh, a large estuarine managed wetland near San Francisco Bay, California,USA, have declined markedly over the last four decades. The reasons for this decline are unclear. Information on how hunting and other factors influence the selection of vegetation types and sanctuaries would be beneficial to manage pintail populations in SuisunMarsh. During 1991-1993, we radio-marked and relocated female pintails (individuals: N = 203, relocations: N = 7,688) within Suisun Marsh to investigate habitat selection during the non-breeding months (winter). We calculated selection ratios for different vegetation types and for sanctuaries, and examined differences in those ratios between hunting season (i.e. hunting and non-hunting), age (hatchyear and after-hatch-year), and time of day (daylight or night hours). We found that diel patterns in selection were influenced by hunting disturbance. For example, prior to the hunting season and during daylight hours, pintails selected areas dominated by brass buttons Cotula coronopifolia, a potentially important food source, usually outside of sanctuary boundaries. However, during the hunting season, pintails did not select brass buttons during daylight hours, but instead highly selected permanent pools, mostly within sanctuaries. Also, during the hunting season, pintails showed strong selection for brass buttons at night. Sanctuaries provided more area of permanent water pools than within hunting areas and appeared to function as important refugia during daylight hours of the hunting season. Wildlife managers should encourage large protected permanent pools adjacent to hunted wetlands to increase pintail numbers within wetland environments and responsibly benefit hunting opportunities while improving pintail conservation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dyson, Anna
Intelligent Facades for High Performance Green Buildings: Previous research and development of intelligent facades systems has been limited in their contribution towards national goals for achieving on-site net zero buildings, because this R&D has failed to couple the many qualitative requirements of building envelopes such as the provision of daylighting, access to exterior views, satisfying aesthetic and cultural characteristics, with the quantitative metrics of energy harvesting, storage and redistribution. To achieve energy self-sufficiency from on-site solar resources, building envelopes can and must address this gamut of concerns simultaneously. With this project, we have undertaken a high-performance building- integrated combined-heat andmore » power concentrating photovoltaic system with high temperature thermal capture, storage and transport towards multiple applications (BICPV/T). The critical contribution we are offering with the Integrated Concentrating Solar Façade (ICSF) is conceived to improve daylighting quality for improved health of occupants and mitigate solar heat gain while maximally capturing and transferring on- site solar energy. The ICSF accomplishes this multi-functionality by intercepting only the direct-normal component of solar energy (which is responsible for elevated cooling loads) thereby transforming a previously problematic source of energy into a high- quality resource that can be applied to building demands such as heating, cooling, dehumidification, domestic hot water, and possible further augmentation of electrical generation through organic Rankine cycles. With the ICSF technology, our team is addressing the global challenge in transitioning commercial and residential building stock towards on-site clean energy self-sufficiency, by fully integrating innovative environmental control systems strategies within an intelligent and responsively dynamic building envelope. The advantage of being able to use the entire solar spectrum for active and passive benefits, along with the potential savings of avoiding transmission losses through direct current (DC) transfer to all buildings systems directly from the site of solar conversion, gives the system a compounded economic viability within the commercial and institutional building markets.« less
Sampling strategies for radio-tracking coyotes
Smith, G.J.; Cary, J.R.; Rongstad, O.J.
1981-01-01
Ten coyotes radio-tracked for 24 h periods were most active at night and moved little during daylight hours. Home-range size determined from radio-locations of 3 adult coyotes increased with the number of locations until an asymptote was reached at about 35-40 independent day locations or 3 6 nights of hourly radio-locations. Activity of the coyote did not affect the asymptotic nature of the home-range calculations, but home-range sizes determined from more than 3 nights of hourly locations were considerably larger than home-range sizes determined from daylight locations. Coyote home-range sizes were calculated from daylight locations, full-night tracking periods, and half-night tracking periods. Full- and half-lnight sampling strategies involved obtaining hourly radio-locations during 12 and 6 h periods, respectively. The half-night sampling strategy was the best compromise for our needs, as it adequately indexed the home-range size, reduced time and energy spent, and standardized the area calculation without requiring the researcher to become completely nocturnal. Sight tracking also provided information about coyote activity and sociability.
Light-scattering properties of a Venetian blind slat used for daylighting applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nilsson, Annica M.; Jonsson, Jacob C.
2010-12-15
The low cost, simplicity, and aesthetic appearance of external and internal shading devices, make them commonly used for daylighting and glare-control applications. Shading devices, such as Venetian blinds, screens, and roller shades, generally exhibit light scattering and/or light redirecting properties. This requires the bi-directional scattering distribution function (BSDF) of the material to be known in order to accurately predict the daylight distribution and energy flow through the fenestration system. Acquiring the complete BSDF is not a straightforward task, and to complete the process it is often required that a model is used to complement the measured data. In this project,more » a Venetian blind slat with a white top surface and a brushed aluminum bottom surface was optically characterized. A goniophotometer and an integrating sphere spectrophotometer were used to determine the angle resolved and hemispherical reflectance of the sample, respectively. The acquired data were fitted to a scattering model providing one Lambertian and one angle dependent description of the surface properties. These were used in combination with raytracing to obtain the complete BSDFs of the Venetian blind system. (author)« less
NASA Astrophysics Data System (ADS)
Amado, L.; Osma, G.; Villamizar, R.
2016-07-01
This paper presents the modelling of lighting behaviour of a hybrid lighting system - HLS in inner spaces for tropical climate. HLS aims to mitigate the problem of high electricity consumption used by artificial lighting in buildings. These systems integrate intelligently the daylight and artificial light through control strategies. However, selection of these strategies usually depends on expertise of designer and of available budget. In order to improve the selection process of the control strategies, this paper analyses the Electrical Engineering Building (EEB) case, initially modelling of lighting behaviour is established for the HLS of a classroom and an office. This allows estimating the illuminance level of the mixed lighting in the space, and energy consumption by artificial light according to different lighting control techniques, a control strategy based on occupancy and a combination of them. The model considers the concept of Daylight Factor (DF) for the estimating of daylight illuminance on the work plane for tropical climatic conditions. The validation of the model was carried out by comparing the measured and model-estimated indoor illuminances.
Determinants of Colour Constancy and the Blue Bias
Gegenfurtner, Karl
2017-01-01
We investigated several sensory and cognitive determinants of colour constancy across 40 illumination hues. In the first experiment, we measured colour naming for the illumination and for the colour induced by the illumination on the colorimetric grey. Results confirmed that the induced colours are approximately complementary to the colour of the illumination. In the second experiment, we measured colour constancy using achromatic adjustments. Average colour constancy was perfect under the blue daylight illumination and decreased in colour directions away from the blue daylight illumination due to undershooting and a strong blue bias. Apart from this blue bias, colour constancy was not related to illumination discrimination and to chromatic detection measured previously with the same setup and stimuli. We also observed a strong negative relationship between the degree of colour constancy and the consensus of naming the illumination colour. Constancy coincided with a low naming consensus, in particular because bluish illumination colours were sometimes seen as achromatic. Blue bias and category consensus alone explained >68%, and all determinants together explained >94% of the variance of achromatic adjustments. These findings suggest that colour constancy is optimised for blue daylight. PMID:29348910
A compact free space quantum key distribution system capable of daylight operation
NASA Astrophysics Data System (ADS)
Benton, David M.; Gorman, Phillip M.; Tapster, Paul R.; Taylor, David M.
2010-06-01
A free space quantum key distribution system has been demonstrated. Consideration has been given to factors such as field of view and spectral width, to cut down the deleterious effect from background light levels. Suitable optical sources such as lasers and RCLEDs have been investigated as well as optimal wavelength choices, always with a view to building a compact and robust system. The implementation of background reduction measures resulted in a system capable of operating in daylight conditions. An autonomous system was left running and generating shared key material continuously for over 7 days.
NASA Astrophysics Data System (ADS)
Gruneisen, Mark T.; Sickmiller, Brett A.; Flanagan, Michael B.; Black, James P.; Stoltenberg, Kurt E.; Duchane, Alexander W.
2016-02-01
Spatial filtering is an important technique for reducing sky background noise in a satellite quantum key distribution downlink receiver. Atmospheric turbulence limits the extent to which spatial filtering can reduce sky noise without introducing signal losses. Using atmospheric propagation and compensation simulations, the potential benefit of adaptive optics (AO) to secure key generation (SKG) is quantified. Simulations are performed assuming optical propagation from a low-Earth-orbit satellite to a terrestrial receiver that includes AO. Higher-order AO correction is modeled assuming a Shack-Hartmann wavefront sensor and a continuous-face-sheet deformable mirror. The effects of atmospheric turbulence, tracking, and higher-order AO on the photon capture efficiency are simulated using statistical representations of turbulence and a time-domain wave-optics hardware emulator. SKG rates are calculated for a decoy-state protocol as a function of the receiver field of view for various strengths of turbulence, sky radiances, and pointing angles. The results show that at fields of view smaller than those discussed by others, AO technologies can enhance SKG rates in daylight and enable SKG where it would otherwise be prohibited as a consequence of background optical noise and signal loss due to propagation and turbulence effects.
Electro-optical system for gunshot detection: analysis, concept, and performance
NASA Astrophysics Data System (ADS)
Kastek, M.; Dulski, R.; Madura, H.; Trzaskawka, P.; Bieszczad, G.; Sosnowski, T.
2011-08-01
The paper discusses technical possibilities to build an effective electro-optical sensor unit for sniper detection using infrared cameras. This unit, comprising of thermal and daylight cameras, can operate as a standalone device but its primary application is a multi-sensor sniper and shot detection system. At first, the analysis was presented of three distinguished phases of sniper activity: before, during and after the shot. On the basis of experimental data the parameters defining the relevant sniper signatures were determined which are essential in assessing the capability of infrared camera to detect sniper activity. A sniper body and muzzle flash were analyzed as targets and the descriptions of phenomena which make it possible to detect sniper activities in infrared spectra as well as analysis of physical limitations were performed. The analyzed infrared systems were simulated using NVTherm software. The calculations for several cameras, equipped with different lenses and detector types were performed. The simulation of detection ranges was performed for the selected scenarios of sniper detection tasks. After the analysis of simulation results, the technical specifications of infrared sniper detection system were discussed, required to provide assumed detection range. Finally the infrared camera setup was proposed which can detected sniper from 1000 meters range.
Hogewoning, Sander W; Douwstra, Peter; Trouwborst, Govert; van Ieperen, Wim; Harbinson, Jeremy
2010-03-01
Plant responses to the light spectrum under which plants are grown affect their developmental characteristics in a complicated manner. Lamps widely used to provide growth irradiance emit spectra which are very different from natural daylight spectra. Whereas specific responses of plants to a spectrum differing from natural daylight may sometimes be predictable, the overall plant response is generally difficult to predict due to the complicated interaction of the many different responses. So far studies on plant responses to spectra either use no daylight control or, if a natural daylight control is used, it will fluctuate in intensity and spectrum. An artificial solar (AS) spectrum which closely resembles a sunlight spectrum has been engineered, and growth, morphogenesis, and photosynthetic characteristics of cucumber plants grown for 13 d under this spectrum have been compared with their performance under fluorescent tubes (FTs) and a high pressure sodium lamp (HPS). The total dry weight of the AS-grown plants was 2.3 and 1.6 times greater than that of the FT and HPS plants, respectively, and the height of the AS plants was 4-5 times greater. This striking difference appeared to be related to a more efficient light interception by the AS plants, characterized by longer petioles, a greater leaf unfolding rate, and a lower investment in leaf mass relative to leaf area. Photosynthesis per leaf area was not greater for the AS plants. The extreme differences in plant response to the AS spectrum compared with the widely used protected cultivation light sources tested highlights the importance of a more natural spectrum, such as the AS spectrum, if the aim is to produce plants representative of field conditions.
NASA Astrophysics Data System (ADS)
Markou, M. T.; Kambezidis, H. D.; Bartzokas, A.; Darula, S.; Kittler, R.
2007-12-01
In this work, daylight reference years (DRYs), based on daylight and solar radiation measurements, are designed for two European cities, Athens, Greece and Bratislava, Slovakia, by using the Danish method, the Festa-Ratto technique and the Modified Sandia National Laboratories methodology. The data basis consists of 5-minute values of global and diffuse horizontal illuminance, global and diffuse horizontal irradiance, zenith luminance and solar altitude as well as of daily values of sunshine duration for 5 years for Athens and 8 years for Bratislava. Moreover, Linke's turbidity factor, luminous turbidity factor and relative sunshine duration are calculated and utilized. Then, for each DRY, the predominant sky-luminance distributions over Athens and Bratislava are identified, by using the methodology of Kittler et al., who corresponded the main sky conditions to 15 theoretical sky standards in diagrams of the ratio of zenith luminance to diffuse horizontal illuminance against solar altitude. For both cities the three aforementioned methods do not create identical DRYs. Despite the differences, the sky types defined for each of the two places seem not to depend on the choice of DRY. The predominant sky standard, for all of them, is a cloudless, polluted sky with a broad solar corona for Athens and an overcast sky with slight brightening towards the sun as well as very clear sky with low atmospheric turbidity for Bratislava. However, the selection of the DRY, which represents best the daylight conditions, is necessary for studies in saving energy in buildings. The DRY, which is created by the Modified Sandia National Laboratories method, is chosen for most cases, while the one created by the Danish method is also useful on certain occasions.
Glass light pipes for solar concentration
NASA Astrophysics Data System (ADS)
Madsen, C. K.; Dogan, Y.; Morrison, M.; Hu, C.; Atkins, R.
2018-02-01
Glass waveguides are fabricated using laser processing techniques that have low optical loss with >90% optical throughput. Advanced light pipes are demonstrated, including angled facets for turning mirrors used for lens-to-light pipe coupling, tapers that increase the concentration, and couplers for combining the outputs from multiple lens array elements. Because they are fabricated from glass, these light pipes can support large optical concentrations and propagate broadband solar over long distances with minimal loss and degradation compared to polymer waveguides. Applications include waveguiding solar concentrators using multi-junction PV cells, solar thermal applications and remoting solar energy, such as for daylighting. Ray trace simulations are used to estimate the surface smoothness required to achieve low loss. Optical measurements for fabricated light pipes are reported for use in waveguiding solar concentrator architectures.
Aqueous-phase source of formic acid in clouds
NASA Technical Reports Server (NTRS)
Chameides, W. L.; Davis, D. D.
1983-01-01
The coupled gas- and aqueous-phase cloud chemistry of HCOOH were examined for controlling factors in the acidity of cloud and rainwater. Attention was given to the aqueous OH/HO2 system that yields an OH species that is highly reactive with other species, notably SO2 and the formaldehyde/formic acid complex. A numerical model was developed to simulate the cloud chemistry in the remote troposphere, with considerations given to CH4-CO-NO(x)-O3-H(x)O(y) system. It was determined that aqueous phase OH radicals can produce and destroy formic acid droplets in daylight conditions, as well as control formic acid levels in rainwater. It is sugested that the same types of reactions may be involved in the control of acetic acid and other organic acids.
Daylight saving time can decrease the frequency of wildlife–vehicle collisions
Ellis, William A.; FitzGibbon, Sean I.; Barth, Benjamin J.; Niehaus, Amanda C.; David, Gwendolyn K.; Taylor, Brendan D.; Matsushige, Helena; Melzer, Alistair; Bercovitch, Fred B.; Carrick, Frank; Jones, Darryl N.; Dexter, Cathryn; Gillett, Amber; Predavec, Martin; Lunney, Dan
2016-01-01
Daylight saving time (DST) could reduce collisions with wildlife by changing the timing of commuter traffic relative to the behaviour of nocturnal animals. To test this idea, we tracked wild koalas (Phascolarctos cinereus) in southeast Queensland, where koalas have declined by 80% in the last 20 years, and compared their movements with traffic patterns along roads where they are often killed. Using a simple model, we found that DST could decrease collisions with koalas by 8% on weekdays and 11% at weekends, simply by shifting the timing of traffic relative to darkness. Wildlife conservation and road safety should become part of the debate on DST. PMID:27881767
Optoelectronic aid for patients with severely restricted visual fields in daylight conditions
NASA Astrophysics Data System (ADS)
Peláez-Coca, María Dolores; Sobrado-Calvo, Paloma; Vargas-Martín, Fernando
2011-11-01
In this study we evaluated the immediate effectiveness of an optoelectronic visual field expander in a sample of subjects with retinitis pigmentosa suffering from a severe peripheral visual field restriction. The aid uses the augmented view concept and provides subjects with visual information from outside their visual field. The tests were carried out in daylight conditions. The optoelectronic aid comprises a FPGA (real-time video processor), a wide-angle mini camera and a transparent see-through head-mounted display. This optoelectronic aid is called SERBA (Sistema Electro-óptico Reconfigurable de Ayuda para Baja Visión). We previously showed that, without compromising residual vision, the SERBA system provides information about objects within an area about three times greater on average than the remaining visual field of the subjects [1]. In this paper we address the effects of the device on mobility under daylight conditions with and without SERBA. The participants were six subjects with retinitis pigmentosa. In this mobility test, better results were obtained when subjects were wearing the SERBA system; specifically, both the number of contacts with low-level obstacles and mobility errors decreased significantly. A longer training period with the device might improve its usefulness.
Periodic catatonia with long-term treatment: a case report.
Chen, Ruei-An; Huang, Tiao-Lai
2017-09-29
Periodic catatonia has long been a challenging diagnosis and there are no absolute guidelines for treatment when precipitating factors are also unclear. We report a schizophrenia patient with periodic catatonia with a 15-year treatment course. A possible correlation between decreased daylight exposure and periodic attacks has been observed. We describe a 49-year-old woman with periodic catatonia associated with schizophrenia with 15 years of follow-up. The patient was treated with the antipsychotics risperidone, haloperidol, loxapine and quetiapine, but catatonia still relapsed once per year during the first few years of her disease course. The treatment was consequently been switched to clozapine due to fluctuated psychotic illness, and a longer duration of remittance was achieved. Lorazepam-diazepam protocol was used for rapid relief of catatonic symptoms, and was able to significantly shorten the duration of the symptoms. In addition, we observed a possible correlation between catatonic episodes and decreased daylight exposure during the 15-year duration. Successful treatment of acute periodic catatonia was achieved with a lorazepam-diazepam protocol, and the patient remained in remission for a longer duration under clozapine treatment. Besides, the possibility of decreased daylight exposure acting as a precipitating factor was observed during our 15 years of follow-up.
Lafer-Sousa, Rosa; Liu, Yang O; Lafer-Sousa, Luis; Wiest, Michael C; Conway, Bevil R
2012-05-01
Colors defined by the two intermediate directions in color space, "orange-cyan" and "lime-magenta," elicit the same spatiotemporal average response from the two cardinal chromatic channels in the lateral geniculate nucleus (LGN). While we found LGN functional magnetic resonance imaging (fMRI) responses to these pairs of colors were statistically indistinguishable, primary visual cortex (V1) fMRI responses were stronger to orange-cyan. Moreover, linear combinations of single-cell responses to cone-isolating stimuli of V1 cone-opponent cells also yielded stronger predicted responses to orange-cyan over lime-magenta, suggesting these neurons underlie the fMRI result. These observations are consistent with the hypothesis that V1 recombines LGN signals into "higher-order" mechanisms tuned to noncardinal color directions. In light of work showing that natural images and daylight samples are biased toward orange-cyan, our findings further suggest that V1 is adapted to daylight. V1, especially double-opponent cells, may function to extract spatial information from color boundaries correlated with scene-structure cues, such as shadows lit by ambient blue sky juxtaposed with surfaces reflecting sunshine. © 2012 Optical Society of America
Daylight coloring for monochrome infrared imagery
NASA Astrophysics Data System (ADS)
Gabura, James
2015-05-01
The effectiveness of infrared imagery in poor visibility situations is well established and the range of applications is expanding as we enter a new era of inexpensive thermal imagers for mobile phones. However there is a problem in that the counterintuitive reflectance characteristics of various common scene elements can cause slowed reaction times and impaired situational awareness-consequences that can be especially detrimental in emergency situations. While multiband infrared sensors can be used, they are inherently more costly. Here we propose a technique for adding a daylight color appearance to single band infrared images, using the normally overlooked property of local image texture. The simple method described here is illustrated with colorized images from the visible red and long wave infrared bands. Our colorizing process not only imparts a natural daylight appearance to infrared images but also enhances the contrast and visibility of otherwise obscure detail. We anticipate that this colorizing method will lead to a better user experience, faster reaction times and improved situational awareness for a growing community of infrared camera users. A natural extension of our process could expand upon its texture discerning feature by adding specialized filters for discriminating specific targets.
Office worker response to an automated venetian blind and electric lighting system: A pilot study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vine, E.; Lee, E.; Clear, R.
1998-03-01
A prototype integrated, dynamic building envelope and lighting system designed to optimize daylight admission and solar heat gain rejection on a real-time basis in a commercial office building is evaluated. Office worker response to the system and occupant-based modifications to the control system are investigated to determine if the design and operation of the prototype system can be improved. Key findings from the study are: (1) the prototype integrated envelope and lighting system is ready for field testing, (2) most office workers (N=14) were satisfied with the system, and (3) there were few complaints. Additional studies are needed to explainmore » how illuminance distribution, lighting quality, and room design can affect workplans illuminance preferences.« less
The effects of surface gloss and roughness on color constancy for real 3-D objects.
Granzier, Jeroen J M; Vergne, Romain; Gegenfurtner, Karl R
2014-02-21
Color constancy denotes the phenomenon that the appearance of an object remains fairly stable under changes in illumination and background color. Most of what we know about color constancy comes from experiments using flat, matte surfaces placed on a single plane under diffuse illumination simulated on a computer monitor. Here we investigate whether material properties (glossiness and roughness) have an effect on color constancy for real objects. Subjects matched the color and brightness of cylinders (painted red, green, or blue) illuminated by simulated daylight (D65) or by a reddish light with a Munsell color book illuminated by a tungsten lamp. The cylinders were either glossy or matte and either smooth or rough. The object was placed in front of a black background or a colored checkerboard. We found that color constancy was significantly higher for the glossy objects compared to the matte objects, and higher for the smooth objects compared to the rough objects. This was independent of the background. We conclude that material properties like glossiness and roughness can have significant effects on color constancy.
Liquid Water in the Extremely Shallow Martian Subsurface
NASA Technical Reports Server (NTRS)
Pavlov, A.; Shivak, J. N.
2012-01-01
Availability of liquid water is one of the major constraints for the potential Martian biosphere. Although liquid water is unstable on the surface of Mars due to low atmospheric pressures, it has been suggested that liquid films of water could be present in the Martian soil. Here we explored a possibility of the liquid water formation in the extremely shallow (1-3 cm) subsurface layer under low atmospheric pressures (0.1-10 mbar) and low ("Martian") surface temperatures (approx.-50 C-0 C). We used a new Goddard Martian simulation chamber to demonstrate that even in the clean frozen soil with temperatures as low as -25C the amount of mobile water can reach several percents. We also showed that during brief periods of simulated daylight warming the shallow subsurface ice sublimates, the water vapor diffuses through porous surface layer of soil temporarily producing supersaturated conditions in the soil, which leads to the formation of additional liquid water. Our results suggest that despite cold temperatures and low atmospheric pressures, Martian soil just several cm below the surface can be habitable.
Daylight saving time can decrease the frequency of wildlife-vehicle collisions.
Ellis, William A; FitzGibbon, Sean I; Barth, Benjamin J; Niehaus, Amanda C; David, Gwendolyn K; Taylor, Brendan D; Matsushige, Helena; Melzer, Alistair; Bercovitch, Fred B; Carrick, Frank; Jones, Darryl N; Dexter, Cathryn; Gillett, Amber; Predavec, Martin; Lunney, Dan; Wilson, Robbie S
2016-11-01
Daylight saving time (DST) could reduce collisions with wildlife by changing the timing of commuter traffic relative to the behaviour of nocturnal animals. To test this idea, we tracked wild koalas (Phascolarctos cinereus) in southeast Queensland, where koalas have declined by 80% in the last 20 years, and compared their movements with traffic patterns along roads where they are often killed. Using a simple model, we found that DST could decrease collisions with koalas by 8% on weekdays and 11% at weekends, simply by shifting the timing of traffic relative to darkness. Wildlife conservation and road safety should become part of the debate on DST. © 2016 The Author(s).
Kittel, T.G.F.; Rosenbloom, N.A.; Royle, J. Andrew; Daly, Christopher; Gibson, W.P.; Fisher, H.H.; Thornton, P.; Yates, D.N.; Aulenbach, S.; Kaufman, C.; McKeown, R.; Bachelet, D.; Schimel, D.S.; Neilson, R.; Lenihan, J.; Drapek, R.; Ojima, D.S.; Parton, W.J.; Melillo, J.M.; Kicklighter, D.W.; Tian, H.; McGuire, A.D.; Sykes, M.T.; Smith, B.; Cowling, S.; Hickler, T.; Prentice, I.C.; Running, S.; Hibbard, K.A.; Post, W.M.; King, A.W.; Smith, T.; Rizzo, B.; Woodward, F.I.
2004-01-01
Analysis and simulation of biospheric responses to historical forcing require surface climate data that capture those aspects of climate that control ecological processes, including key spatial gradients and modes of temporal variability. We developed a multivariate, gridded historical climate dataset for the conterminous USA as a common input database for the Vegetation/Ecosystem Modeling and Analysis Project (VEMAP), a biogeochemical and dynamic vegetation model intercomparison. The dataset covers the period 1895-1993 on a 0.5?? latitude/longitude grid. Climate is represented at both monthly and daily timesteps. Variables are: precipitation, mininimum and maximum temperature, total incident solar radiation, daylight-period irradiance, vapor pressure, and daylight-period relative humidity. The dataset was derived from US Historical Climate Network (HCN), cooperative network, and snowpack telemetry (SNOTEL) monthly precipitation and mean minimum and maximum temperature station data. We employed techniques that rely on geostatistical and physical relationships to create the temporally and spatially complete dataset. We developed a local kriging prediction model to infill discontinuous and limited-length station records based on spatial autocorrelation structure of climate anomalies. A spatial interpolation model (PRISM) that accounts for physiographic controls was used to grid the infilled monthly station data. We implemented a stochastic weather generator (modified WGEN) to disaggregate the gridded monthly series to dailies. Radiation and humidity variables were estimated from the dailies using a physically-based empirical surface climate model (MTCLIM3). Derived datasets include a 100 yr model spin-up climate and a historical Palmer Drought Severity Index (PDSI) dataset. The VEMAP dataset exhibits statistically significant trends in temperature, precipitation, solar radiation, vapor pressure, and PDSI for US National Assessment regions. The historical climate and companion datasets are available online at data archive centers. ?? Inter-Research 2004.
Development of Design Guidance for K-12 Schools: From 30% to 50% Energy Savings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pless, S.; Torcellini, P.; Long, N.
2008-01-01
This paper describes the development of energy efficiency recommendations for achieving 30% whole-building energy savings in K-12 Schools over levels achieved by following the ANSI/ASHRAE/IESNA Standard 90.1, Energy Standard for Buildings Except Low-Rise Residential Buildings (1999 and 2004 versions). Exhaustive simulations were run to create packages of energy design solutions available over a wide range of K-12 schools and climates. These design recommendations look at building envelope, fenestration, lighting systems (including electrical lights and daylighting), HVAC systems, building automation and controls, outside air treatment, and service water heating. We document and discuss the energy modeling performed to demonstrate that themore » recommendations will result in at least 30% energy savings over ASHRAE 90.1-1999 and ASHRAE 90.1-2004. Recommendations are evaluated based on the availability of daylighting for the school and by the type of HVAC system. Compared to the ASHRAE 90.1-1999 baseline, the recommendations result in more than 30% savings in all climate zones for both daylit and nondaylit elementary, middle, and high schools with a range of HVAC system types. These recommendations have been included in the Advanced Energy Design Guide for K-12 School Buildings. Compared to the more stringent ASHRAE 90.1-2004 baseline, the recommendations result in more than 30% savings in all climate zones, for only the daylit elementary, middle, and high schools, with a range of HVAC system types. To inform the future development of recommendations for higher level of energy savings, we analyzed a subset of recommendations to understand which energy efficiency technologies would be needed to achieve 50% energy savings.« less
A magnetic compass aids monarch butterfly migration
Guerra, Patrick A; Gegear, Robert J; Reppert, Steven M
2014-01-01
Convincing evidence that migrant monarch butterflies (Danaus plexippus) use a magnetic compass to aid their fall migration has been lacking from the spectacular navigational capabilities of this species. Here we use flight simulator studies to show that migrants indeed possess an inclination magnetic compass to help direct their flight equatorward in the fall. The use of this inclination compass is light-dependent utilizing ultraviolet-A/blue light between 380 and 420 nm. Notably, the significance of light <420 nm for inclination compass function was not considered in previous monarch studies. The antennae are important for the inclination compass because they appear to contain light-sensitive magnetosensors. For migratory monarchs, the inclination compass may serve as an important orientation mechanism when directional daylight cues are unavailable and may also augment time-compensated sun compass orientation for appropriate directionality throughout the migration. PMID:24960099
What Is the Reference? An Examination of Alternatives to the Reference Sources Used in IES TM-30-15
DOE Office of Scientific and Technical Information (OSTI.GOV)
Royer, Michael P.
A study was undertaken to document the role of the reference illuminant in the IES TM-30-15 method for evaluating color rendition. TM-30-15 relies on a relative reference scheme; that is, the reference illuminant and test source always have the same correlated color temperature (CCT). The reference illuminant is a Planckian radiator, model of daylight, or combination of those two, depending on the exact CCT of the test source. Three alternative reference schemes were considered: 1) either using all Planckian radiators or all daylight models; 2) using only one of ten possible illuminants (Planckian, daylight, or equal energy), regardless of themore » CCT of the test source; 3) using an off-Planckian reference illuminant (i.e., a source with a negative Duv). No reference scheme is inherently superior to another, with differences in metric values largely a result of small differences in gamut shape of the reference alternatives. While using any of the alternative schemes is more reasonable in the TM-30-15 evaluation framework than it was with the CIE CRI framework, the differences still ultimately manifest only as changes in interpretation of the results. References are employed in color rendering measures to provide a familiar point of comparison, not to establish an ideal source.« less
Decreased retinal sensitivity in depressive disorder: a controlled study.
Berman, G; Muttuvelu, D; Berman, D; Larsen, J I; Licht, R W; Ledolter, J; Kardon, R H
2018-03-01
To compare pupil responses in depressed patients with a seasonal pattern, depressed patients without a seasonal pattern and healthy controls as a function of daylight hours on the testing day. Patients suffering from a major depressive episode were included in wintertime. The pupil light reflex was measured at inclusion and in the following summer using a binocular pupillometer. A protocol of low (1 lux) and high (400 lux) intensity red and blue lights was used to assess rod, cone and melanopsin-containing intrinsic photosensitive retinal ganglion cell input to the pupil reflex. The mean group pupil responses associated with a melanopsin-mediated sustained pupil response at 400 lux blue light were significantly reduced in the depressed subjects (N = 39) as compared to the healthy controls (N = 24) (P = 0.023). Across all groups, a reduction in number of daylight hours was significantly associated with a reduction in sustained pupil response (P = 0.007). All groups showed an equal effect of daylight hours on the melanopsin-mediated sustained pupil response. The melanopsin-mediated sustained pupil contraction to offset of high-intensity blue light is reduced in depressed patients. These results further emphasize the interaction of light exposure with depression. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Natural light illumination system.
Whang, Allen Jong-Woei; Chen, Yi-Yung; Yang, Shu-Hua; Pan, Po-Hsuan; Chou, Kao-Hsu; Lee, Yu-Chi; Lee, Zong-Yi; Chen, Chi-An; Chen, Cheng-Nan
2010-12-10
In recent years, green energy has undergone a lot of development and has been the subject of many applications. Many research studies have focused on illumination with sunlight as a means of saving energy and creating healthy lighting. Natural light illumination systems have collecting, transmitting, and lighting elements. Today, most daylight collectors use dynamic concentrators; these include Sun tracking systems. However, this design is too expensive to be cost effective. To create a low-cost collector that can be easily installed on a large building, we have designed a static concentrator, which is prismatic and cascadable, to collect sunlight for indoor illumination. The transmission component uses a large number of optical fibers. Because optical fibers are expensive, this means that most of the cost for the system will be related to transmission. In this paper, we also use a prismatic structure to design an optical coupler for coupling n to 1. With the n-to-1 coupler, the number of optical fibers necessary can be greatly reduced. Although this new natural light illumination system can effectively guide collected sunlight and send it to the basement or to other indoor places for healthy lighting, previously there has been no way to manage the collected sunlight when lighting was not desired. To solve this problem, we have designed an optical switch and a beam splitter to control and separate the transmitted light. When replacing traditional sources, the lighting should have similar characteristics, such as intensity distribution and geometric parameters, to those of traditional artificial sources. We have designed, simulated, and optimized an illumination lightpipe with a dot pattern to redistribute the collected sunlight from the natural light illumination system such that it equals the qualities of a traditional lighting system. We also provide an active lighting module that provides lighting from the natural light illumination system or LED auxiliary sources, depending on circumstances. The system is controlled by a light detector. We used optical simulation tools to design and simulate the efficiency of the active module. Finally, we used the natural light illumination system to provide natural illumination for a traffic tunnel. This system will provide a great number of benefits for the people who use it.
Gongruttananun, N
2011-12-01
In total, 120 Thai-native pullets (Gallus domesticus) aged 18 wk were housed in floor pens, located in a conventional open-sided shed under natural daylight (12L:12D) and randomly divided into 3 groups; Groups 1 (DF) and 2 (DR) were reared under natural daylight and supplemented with fluorescent or red light, respectively, whereas group 3 (R) was maintained in light-controlled pens and exposed only to red light. The red light was produced by light-emitting diodes. All treatments were provided with 16 h of light per day (16L:8D) during a 26-wk egg-laying period, and there were 4 replicate pens of 10 hens for each treatment. Photostimulation of these light sources was initiated at 18 wk of age and subsequent effects on reproductive performance were observed during the experimental period. Morphological characteristics of the eyes and eggshell microstructure were examined at the end of the study. Feed and water were provided ad libitum. There were no significant differences in BW, feed intake, egg weight, egg quality, or mortality rate due to the treatment. Pullets in the R and DR treatment groups commenced egg production significantly earlier than those in the DF treatment group. In early-season egg production (0-8 wk), cumulative egg number was significantly (P < 0.05) higher for the R treatment (25.9 eggs/hen) than for the DR (20.9) and DF (19.5) treatment groups. No significant differences in total egg production per hen occurred among the treatment groups. At 2 wk following photostimulation, hens in the R treatment group had significantly (P < 0.05) higher serum estradiol concentrations compared with hens in the other treatment groups. Neither eggshell structure nor eye morphology was affected by the treatments. It was concluded that the spectrum of red light did not affect live performance, egg production, egg quality, eggshell microstructure, or eye morphology of Thai-native hens, except for in accelerating sexual development. The light-emitting diode lighting system would be beneficial for energy savings and the reduction of rearing costs.
Warrant, Eric J; Locket, N Adam
2004-08-01
The deep sea is the largest habitat on earth. Its three great faunal environments--the twilight mesopelagic zone, the dark bathypelagic zone and the vast flat expanses of the benthic habitat--are home to a rich fauna of vertebrates and invertebrates. In the mesopelagic zone (150-1000 m), the down-welling daylight creates an extended scene that becomes increasingly dimmer and bluer with depth. The available daylight also originates increasingly from vertically above, and bioluminescent point-source flashes, well contrasted against the dim background daylight, become increasingly visible. In the bathypelagic zone below 1000 m no daylight remains, and the scene becomes entirely dominated by point-like bioluminescence. This changing nature of visual scenes with depth--from extended source to point source--has had a profound effect on the designs of deep-sea eyes, both optically and neurally, a fact that until recently was not fully appreciated. Recent measurements of the sensitivity and spatial resolution of deep-sea eyes--particularly from the camera eyes of fishes and cephalopods and the compound eyes of crustaceans--reveal that ocular designs are well matched to the nature of the visual scene at any given depth. This match between eye design and visual scene is the subject of this review. The greatest variation in eye design is found in the mesopelagic zone, where dim down-welling daylight and bio-luminescent point sources may be visible simultaneously. Some mesopelagic eyes rely on spatial and temporal summation to increase sensitivity to a dim extended scene, while others sacrifice this sensitivity to localise pinpoints of bright bioluminescence. Yet other eyes have retinal regions separately specialised for each type of light. In the bathypelagic zone, eyes generally get smaller and therefore less sensitive to point sources with increasing depth. In fishes, this insensitivity, combined with surprisingly high spatial resolution, is very well adapted to the detection and localisation of point-source bioluminescence at ecologically meaningful distances. At all depths, the eyes of animals active on and over the nutrient-rich sea floor are generally larger than the eyes of pelagic species. In fishes, the retinal ganglion cells are also frequently arranged in a horizontal visual streak, an adaptation for viewing the wide flat horizon of the sea floor, and all animals living there. These and many other aspects of light and vision in the deep sea are reviewed in support of the following conclusion: it is not only the intensity of light at different depths, but also its distribution in space, which has been a major force in the evolution of deep-sea vision.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Tengfang; Piette, Mary Ann
2004-08-05
The original scope of work was to obtain and analyze existing and emerging data in four states: California, Florida, New York, and Wisconsin. The goal of this data collection was to deliver a baseline database or recommendations for such a database that could possibly contain window and daylighting features and energy performance characteristics of Kindergarten through 12th grade (K-12) school buildings (or those of classrooms when available). In particular, data analyses were performed based upon the California Commercial End-Use Survey (CEUS) databases to understand school energy use, features of window glazing, and availability of daylighting in California K-12 schools. Themore » outcomes from this baseline task can be used to assist in establishing a database of school energy performance, assessing applications of existing technologies relevant to window and daylighting design, and identifying future R&D needs. These are in line with the overall project goals as outlined in the proposal. Through the review and analysis of this data, it is clear that there are many compounding factors impacting energy use in K-12 school buildings in the U.S., and that there are various challenges in understanding the impact of K-12 classroom energy use associated with design features of window glazing and skylight. First, the energy data in the existing CEUS databases has, at most, provided the aggregated electricity and/or gas usages for the building establishments that include other school facilities on top of the classroom spaces. Although the percentage of classroom floor area in schools is often available from the databases, there is no additional information that can be used to quantitatively segregate the EUI for classroom spaces. In order to quantify the EUI for classrooms, sub-metering of energy usage by classrooms must be obtained. Second, magnitudes of energy use for electricity lighting are not attainable from the existing databases, nor are the lighting levels contributed by artificial lighting or daylight. It is impossible to reasonably estimate the lighting energy consumption for classroom areas in the sample of schools studied in this project. Third, there are many other compounding factors that may as well influence the overall classroom energy use, e.g., ventilation, insulation, system efficiency, occupancy, control, schedules, and weather. Fourth, although we have examined the school EUI grouped by various factors such as climate zones, window and daylighting design features from the California databases, no statistically significant associations can be identified from the sampled California K-12 schools in the current California CEUS. There are opportunities to expand such analyses by developing and including more powerful CEUS databases in the future. Finally, a list of parameters is recommended for future database development and for use of future investigation in K-12 classroom energy use, window and skylight design, and possible relations between them. Some of the key parameters include: (1) Energy end use data for lighting systems, classrooms, and schools; (2) Building design and operation including features for windows and daylighting; and (3) Other key parameters and information that would be available to investigate overall energy uses, building and systems design, their operation, and services provided.« less
Time Periods of Unusual Density Behavior Observed by GRACE and CHAMP
NASA Astrophysics Data System (ADS)
McLaughlin, C. A.; Fattig, E.; Mysore Krishna, D.; Locke, T.; Mehta, P. M.
2011-12-01
Time periods of low cross correlation between precision orbit ephemeris (POE) derived density and accelerometer density for CHAMP and GRACE are examined. In particular, the cross correlation for GRACE dropped from typical values near 0.9 to much lower values and then returned to typical over the time period of late October to late December of 2005. This time period includes a maneuver where GRACE-A and GRACE-B swapped positions. However, the drop in cross correlation begins and reaches its low point before the maneuvers begin. In addition, the densities were found using GRACE-A, but GRACE-B did most of the maneuvering. The time period is characterized by high frequency variations in accelerometer density of the same magnitude as the daylight to eclipse variations over the course of an orbit. However, the daylight to eclipse variations are particularly small during this time period because the orbit plane is near the terminator. Additionally, the difference between the accelerometer and POE derived densities are not unusually large during this time period. This implies the variations are not unusual, just more significant when the orbit plane is near terminator. Cyclical variations in correlation of the POE derived densities with accelerometer derived densities are seen for both GRACE and CHAMP, but the magnitude of the variations are much larger for GRACE, possibly because of the higher altitude of GRACE. The cycles seem to be phased so that low correlations occur with low beta angle when the orbit plane is near the terminator. The low correlation is possibly caused by the lower amplitude of the daylight to eclipse signal making higher frequency variations relatively more important. However, another possible explanation is terminator waves in density that propagate to the thermosphere from lower in the atmosphere. These waves have been observed in CHAMP accelerometer data and global circulation model simulations. Further investigation is needed to see if the variations correspond to terminator waves or if they represent typical high frequency signal from another source that is more apparent when the orbit plane is near the terminator. 1. C. A. McLaughlin, E. Fattig, D. Mysore Krishna, and P. M. Mehta, "Time Periods of Anomalous Density for GRACE and CHAMP," AAS/AIAA Astrodynamics Specialists Conference, AAS 11-613, Girdwood, AK, August 2011. 2. C. A. McLaughlin, A. Hiatt, and T. Lechtenberg, "Calibrating Precision Orbit Derived Total Density," Journal of Spacecraft and Rockets, Vol. 48, No. 1, January-February 2011, pp. 166-174.
Pushing Stellarium to the Limit for Astronomy Distance Education
NASA Astrophysics Data System (ADS)
Connors, Martin
2016-01-01
The freeware planetarium program Stellarium (www.stellarium.org) provides a high quality astronomical simulation which can be stimulating for students of all ages. Athabasca University has been offering distance education astronomy courses using computer simulations of the night sky for nearly three decades. A recurring theme has been the challenge of matching available software to the computers available to students in their homes. Stellarium is useful in this respect in being available as downloadable freeware for Windows, Mac, and linux, and available from third parties for other platforms. Stellarium is useful for giving a qualitative idea of sky movements that take place slowly in nature. A night, or even a year, can be presented in sped up time, or with large time steps allowing to see changes. Our Science-stream freshman course emphasizes quantitative analysis, and Stellarium is also useful for this. Plotting the Sun's position at noon (allowing for Daylight Savings Time) gives an analemma from which the obliquity can be readily calculated. The Moon's daily motion can be measured in degrees with local declination lines as a reference, allowing the eccentricity of its orbit to be demonstrated. Plotting retrograde loops for outer planets corrects the misimpression students sometimes develop that this is a phenomenon restricted to Mars. For both inner and outer planets, the relation of synodic and sidereal periods may be explored quantitatively. Most recently we are exploring the possibility of replacing our HR diagram and Hubble Law plots with data gathered from Stellarium. Data in these is not directly measured as are the variables in planetary motion labs, but an observational feel can be added to labs that otherwise (if done using published tables of data) could seem divorced from observation. Stellarium can help attain a large number of objectives in introductory astronomy education, from truly understanding basic phenomena to making and interpreting quantitative measurements.
Incidence of myocardial infarction with shifts to and from daylight savings time.
Jiddou, Monica R; Pica, Mark; Boura, Judy; Qu, Lihua; Franklin, Barry A
2013-03-01
Modulators of normal bodily functions such as the duration and quality of sleep might transiently influence cardiovascular risk. The transition to daylight savings time (DST) has been associated with a short-term increased incidence ratio (IR) of acute myocardial infarction (AMI). The present retrospective study examined the IR of AMIs that presented to our hospitals the week after DST and after the autumn switch to standard time, October 2006 to April 2012, with specific reference to the AMI type. Our study population (n = 935 patients; 59% men, 41% women) was obtained from the electronic medical records of the Royal Oak and Troy campuses of the Beaumont Hospitals in Michigan. Overall, the frequency of AMI was similar in the spring and autumn, 463 (49.5%) and 472 (50.5%), respectively. The IR for the first week after the spring shift was 1.17 (95% confidence interval 1.00 to 1.36). After the transition from DST in the autumn, the IR for the same period was lower, but not significantly different, 0.99 (95% confidence interval 0.85 to 1.16). Nevertheless, the greatest increase in AMI occurred on the first day (Sunday) after the spring shift to DST (1.71, 95% confidence interval 1.09 to 2.02; p <0.05). Also, a significantly greater incidence was found of non-ST-segment myocardial infarction after the transition to DST in the study group compared with that in the control group (p = 0.022). In conclusion, these data suggest that shifts to and from DST might transiently affect the incidence and type of acute cardiac events, albeit modestly. Copyright © 2013 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Britz, S. J.; Sager, J. C.; Knott, W. M. (Principal Investigator)
1990-01-01
The role of blue light in plant growth and development was investigated in soybean (Glycine max [L.] Merr. cv Williams) and sorghum (Sorghum bicolor [L.] Moench. cv Rio) grown under equal photosynthetic photon fluxes (approximately 500 micromoles per square meter per second) from broad spectrum daylight fluorescent or blue-deficient, narrow-band (589 nanometers) low pressure sodium (LPS) lamps. Between 14 and 18 days after sowing, it was possible to relate adaptations in photosynthesis and leaf growth to dry matter accumulation. Soybean development under LPS light was similar in several respects to that of shaded plants, consistent with an important role for blue light photoreceptors in regulation of growth response to irradiance. Thus, soybeans from LPS conditions partitioned relatively more growth to leaves and maintained higher average leaf area ratios (mean LAR) that compensated lower net assimilation rates (mean NAR). Relative growth rates were therefore comparable to plants from daylight fluorescent lamps. Reductions in mean NAR were matched by lower rates of net photosynthesis (A) on an area basis in the major photosynthetic source (first trifoliolate) leaf. Lower A in soybean resulted from reduced leaf dry matter per unit leaf area, but lower A under LPS conditions in sorghum correlated with leaf chlorosis and reduced total nitrogen (not observed in soybean). In spite of a lower A, mean NAR was larger in sorghum from LPS conditions, resulting in significantly greater relative growth rates (mean LAR was approximately equal for both light conditions). Leaf starch accumulation rate was higher for both species and starch content at the end of the dark period was elevated two- and three-fold for sorghum and soybean, respectively, under LPS conditions. Possible relations between starch accumulation, leaf export, and plant growth in response to spectral quality were considered.
van Kasteren, Yasmin; Bradford, Dana; Zhang, Qing; Karunanithi, Mohan; Ding, Hang
2017-06-13
An ongoing challenge for smart homes research for aging-in-place is how to make sense of the large amounts of data from in-home sensors to facilitate real-time monitoring and develop reliable alerts. The objective of our study was to explore the usefulness of a routine-based approach for making sense of smart home data for the elderly. Maximum variation sampling was used to select three cases for an in-depth mixed methods exploration of the daily routines of three elderly participants in a smart home trial using 180 days of power use and motion sensor data and longitudinal interview data. Sensor data accurately matched self-reported routines. By comparing daily movement data with personal routines, it was possible to identify changes in routine that signaled illness, recovery from bereavement, and gradual deterioration of sleep quality and daily movement. Interview and sensor data also identified changes in routine with variations in temperature and daylight hours. The findings demonstrated that a routine-based approach makes interpreting sensor data easy, intuitive, and transparent. They highlighted the importance of understanding and accounting for individual differences in preferences for routinization and the influence of the cyclical nature of daily routines, social or cultural rhythms, and seasonal changes in temperature and daylight hours when interpreting information based on sensor data. This research has demonstrated the usefulness of a routine-based approach for making sense of smart home data, which has furthered the understanding of the challenges that need to be addressed in order to make real-time monitoring and effective alerts a reality. ©Yasmin van Kasteren, Dana Bradford, Qing Zhang, Mohan Karunanithi, Hang Ding. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 13.06.2017.
van Kasteren, Yasmin; Bradford, Dana; Karunanithi, Mohan; Ding, Hang
2017-01-01
Background An ongoing challenge for smart homes research for aging-in-place is how to make sense of the large amounts of data from in-home sensors to facilitate real-time monitoring and develop reliable alerts. Objective The objective of our study was to explore the usefulness of a routine-based approach for making sense of smart home data for the elderly. Methods Maximum variation sampling was used to select three cases for an in-depth mixed methods exploration of the daily routines of three elderly participants in a smart home trial using 180 days of power use and motion sensor data and longitudinal interview data. Results Sensor data accurately matched self-reported routines. By comparing daily movement data with personal routines, it was possible to identify changes in routine that signaled illness, recovery from bereavement, and gradual deterioration of sleep quality and daily movement. Interview and sensor data also identified changes in routine with variations in temperature and daylight hours. Conclusions The findings demonstrated that a routine-based approach makes interpreting sensor data easy, intuitive, and transparent. They highlighted the importance of understanding and accounting for individual differences in preferences for routinization and the influence of the cyclical nature of daily routines, social or cultural rhythms, and seasonal changes in temperature and daylight hours when interpreting information based on sensor data. This research has demonstrated the usefulness of a routine-based approach for making sense of smart home data, which has furthered the understanding of the challenges that need to be addressed in order to make real-time monitoring and effective alerts a reality. PMID:28611014
Energy Smart Schools--Applied Research, Field Testing, and Technology Integration
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nebiat Solomon; Robin Vieira; William L. Manz
2004-12-01
The National Association of State Energy Officials (NASEO) in conjunction with the California Energy Commission, the Energy Center of Wisconsin, the Florida Solar Energy Center, the New York State Energy Research and Development Authority, and the Ohio Department of Development's Office of Energy Efficiency conducted a four-year, cost-share project with the U.S. Department of Energy (USDOE), Office of Energy Efficiency and Renewable Energy to focus on energy efficiency and high-performance technologies in our nation's schools. NASEO was the program lead for the MOU-State Schools Working group, established in conjunction with the USDOE Memorandum of Understanding process for collaboration among statemore » and federal energy research and demonstration offices and organizations. The MOU-State Schools Working Group included State Energy Offices and other state energy research organizations from all regions of the country. Through surveys and analyses, the Working Group determined the school-related energy priorities of the states and established a set of tasks to be accomplished, including the installation and evaluation of microturbines, advanced daylighting research, testing of schools and classrooms, and integrated school building technologies. The Energy Smart Schools project resulted in the adoption of advanced energy efficiency technologies in both the renovation of existing schools and building of new ones; the education of school administrators, architects, engineers, and manufacturers nationwide about the energy-saving, economic, and environmental benefits of energy efficiency technologies; and improved the learning environment for the nation's students through use of better temperature controls, improvements in air quality, and increased daylighting in classrooms. It also provided an opportunity for states to share and replicate successful projects to increase their energy efficiency while at the same time driving down their energy costs.« less
Solar collector with altitude tracking
Barak, Amitzur Z.
1977-01-01
A device is provided for turning a solar collector about an east-west horizontal axis so that the collector is tilted toward the sun as the EWV altitude of the sun varies each day. It includes one or more heat responsive elements and a shading means aligned so that within a range of EWV altitudes of the sun during daylight hours the shading means shades the element or elements while during the rest of the daylight hours the elements or elements are heated by the sun to assume heated, stable states. Mechanical linkage between the collector and the element is responsive to the states of the element or elements to tilt the collector in accordance with variations in the EWV altitude of the sun.
Impact of daylight savings time on spontaneous pregnancy loss in in vitro fertilization patients.
Liu, Constance; Politch, Joseph A; Cullerton, Evan; Go, Kathryn; Pang, Samuel; Kuohung, Wendy
2017-01-01
Transition into daylight savings time (DST) has studied negative impacts on health, but little is known regarding impact on fertility. This retrospective cohort study evaluates DST impact on pregnancy and pregnancy loss rates in 1,654 autologous in vitro fertilization cycles (2009 to 2012). Study groups were identified based on the relationship of DST to embryo transfer. Pregnancy rates were similar in Spring and Fall (41.4%, 42.2%). Pregnancy loss rates were also comparable between Spring and Fall (15.5%, 17.1%), but rates of loss were significantly higher in Spring when DST occurred after embryo transfer (24.3%). Loss was marked in patients with a history of prior spontaneous pregnancy loss (60.5%).
LeRoy Doggett and Daylight Saving Time: A Reminiscence
NASA Astrophysics Data System (ADS)
Bartky, I. R.
1997-12-01
Daylight Saving Time (DST) has been a concern of Congress ever since its adoption in 1918. Yet, not until 1976 did Members of Congress have astronomical, geographic and demographic information in terms of the country's Standard Time zones. This information and various impact analyses were developed by the National Bureau of Standards (NBS) at the request of the House of Representatives, which was reviewing the effects of a two-year, DST experiment on the American public. The displays in the study gave legislators a way to consider alternate observance periods in a systematic manner. The leader of the DST study team will detail LeRoy Doggett's involvement during the hectic, three-month analysis period that culminated with NBS officials testifying before Congress.
[Current recommendations for deceleration of myopia progression].
Lagrèze, W A; Joachimsen, L; Schaeffel, F
2017-01-01
Epidemiologic data demonstrate a rise in myopia prevalence. Therefore interventions to reduce the risk of myopia and its progression are needed and increasingly often asked for. Systematic literature search via PubMed in MEDLINE. Myopia progression can be reduced by the following means which are listed according to their efficacy: (1) Atropine eye drops low dosed to avoid clinically relevant side effects, (2) optical means aiming at the correction of peripheral hyperopic defocus, e. g., multifocal contact lenses, and (3) increased daylight exposure. Daylight exposure reduces the risk of incident myopia. Children should be advised to spend sufficient time outdoors, especially before and in primary school. Myopia progression can be effectively attenuated by low-dose topical atropine and multifocal contact lenses.
Hurricane Celia off the Pacific Coast of Mexico
2004-07-23
Hurricane Celia as observed by NASA's spaceborne Atmospheric Infrared Sounder (AIRS). This image shows Celia on July 23 in visible light, as you would perceive it from space. Located in the eastern north Pacific Ocean off the coast of Mexico, Celia's winds have now dissipated to highs of 40 mph. Celia was the first hurricane of the eastern north Pacific season. Figure 1 is a daylight snapshot taken on July 19; Celia as tropical storm, winds at 50mph. Figure 2 is a daylight snapshot taken on July 21; Celia has a small eye with an 80-90% closed eyewall; sustained winds at 75mph with gusts reaching 92mph; Celia is upgraded to hurricane status. http://photojournal.jpl.nasa.gov/catalog/PIA00438
Television image compression and small animal remote monitoring
NASA Technical Reports Server (NTRS)
Haines, Richard F.; Jackson, Robert W.
1990-01-01
It was shown that a subject can reliably discriminate a difference in video image quality (using a specific commercial product) for image compression levels ranging from 384 kbits per second to 1536 kbits per second. However, their discriminations are significantly influenced by whether or not the TV camera is stable or moving and whether or not the animals are quiescent or active, which is correlated with illumination level (daylight versus night illumination, respectively). The highest video rate used here was 1.54 megabits per second, which is about 18 percent of the so-called normal TV resolution of 8.4MHz. Since this video rate was judged to be acceptable by 27 of the 34 subjects (79 percent), for monitoring the general health and status of small animals within their illuminated (lights on) cages (regardless of whether the camera was stable or moved), it suggests that an immediate Space Station Freedom to ground bandwidth reduction of about 80 percent can be tolerated without a significant loss in general monitoring capability. Another general conclusion is that the present methodology appears to be effective in quantifying visual judgments of video image quality.
A review of spatial comfort in shophouse in humid tropics
NASA Astrophysics Data System (ADS)
Hilma Sari, Laina; Zulfa Yuzni, Siti; Haiqal, Muhammad; Evalina, Z.
2018-05-01
Shophouse is the most building type built along the road with various commercial functions. Due to the high rate of land price and the high percentage of building basic coefficient, therefore the shophouse is commonly built in maximum. This characteristic creates a lack of apertures through the buildings due to being trapped by surrounding shophouses. Shophouses are also built in heavyweight construction, i.e., concrete and brickwork. Due to such limitations, this study aims at assessing the spatial comfort of the shophouse, i.e., thermal and lighting. It is quite visible that quality. This study was carried out through the field measurement. Taking Banda Aceh climate as the case study in humid tropics, this study found that the high inside air temperature mostly runs throughout the upper floor during the day, and the ground floor during the night; and the small value of daylight occurs almost on the entire rooms during the day. This paper further proposes the possibility to improve the comfort quality in the shophouse which is conducted through the literature survey.
Endogenous modulation of human visual cortex activity improves perception at twilight.
Cordani, Lorenzo; Tagliazucchi, Enzo; Vetter, Céline; Hassemer, Christian; Roenneberg, Till; Stehle, Jörg H; Kell, Christian A
2018-04-10
Perception, particularly in the visual domain, is drastically influenced by rhythmic changes in ambient lighting conditions. Anticipation of daylight changes by the circadian system is critical for survival. However, the neural bases of time-of-day-dependent modulation in human perception are not yet understood. We used fMRI to study brain dynamics during resting-state and close-to-threshold visual perception repeatedly at six times of the day. Here we report that resting-state signal variance drops endogenously at times coinciding with dawn and dusk, notably in sensory cortices only. In parallel, perception-related signal variance in visual cortices decreases and correlates negatively with detection performance, identifying an anticipatory mechanism that compensates for the deteriorated visual signal quality at dawn and dusk. Generally, our findings imply that decreases in spontaneous neural activity improve close-to-threshold perception.
Wood, Simon; Quinn, Alison; Troupe, Stephen; Kingsland, Charles; Lewis-Jones, Iwan
2006-12-01
The effect of seasonality and daylight length on mammalian reproduction leading to spring births has been well established, and is known as photoperiodism. In assisted reproduction there is much greater uncertainty as to the effect of seasonality. This was a 4-year retrospective analysis of 2709 standardised cycles of IVF/ICSI. Data was analysed with regard to the 1642 cycles occurring during the months of extended daylight (Apr-Sept) and those 1067 cycles during winter months of restricted light length (Oct-Mar). The results showed that there was significant improvement in assisted conception outcomes in cycles performed in summer (lighter) months with more efficient ovarian stimulation 766iu v880iu/per oocyte retrieved (p=0.006). There was similarly a significantly improved implantation rate per embryo transferred 11.42% vs 9.35% (p=0.011) and greater clinical pregnancy rate 20% vs 15% (p=0.0033) during summer cycles. This study appears to demonstrate a significant benefit of increased daylight length on outcomes of IVF/ICSI cycles. Whilst the exact mechanism of this is unclear, it would seem probable that melatonin may have actions at multiple sites and on multiple levels of the reproductive tract, and may exert a more profound effect on outcomes of assisted conception cycles than has been previously considered.
NASA Astrophysics Data System (ADS)
Maiwald, M.; Müller, A.; Sumpf, B.
2017-02-01
In-situ shifted excitation Raman difference spectroscopy (SERDS) experiments are presented using a portable sensor system. Key elements of this system are an in-house developed handheld probe with an implemented dual-wavelength diode laser at 785 nm. An optical power of 120 mW is achieved ex probe. Raman experiments are carried out in the laboratory for qualification using polystyrene as test sample. Here, a shot-noise limited signal-to-noise ratio (SNR) of 120 is achieved. Stability tests were performed and show a stable position of the Raman line under study within 0.1 cm-1 and a stable Raman intensity better +/- 2% mainly limited by shot noise interference. SERDS experiments are carried out in an apple orchard for demonstration. Green apple leafs are used as test samples. The Raman spectra show huge background interferences by fluorescence and ambient daylight which almost obscure Raman signals from green leafs. The selected excitation power is 50 mW and the exposure time is 0.2 s to avoid detector saturation. SERDS efficiently separates the Raman signals from fluorescence and daylight contributions and generates an 11-fold improvement of the signal-to-background noise with respect to the measured Raman signals. The results demonstrate the capability of the portable SERDS system and enable rapid in-situ and undisturbed Raman investigations under daylight conditions.
Marra, Kayla; LaRochelle, Ethan P; Chapman, M Shane; Hoopes, P Jack; Lukovits, Karina; Maytin, Edward V; Hasan, Tayyaba; Pogue, Brian W
2018-04-16
Daylight-mediated photodynamic therapy (d-PDT) as a treatment for actinic keratosis (AK) is an increasingly common technique due to a significant reduction in pain, leading to better patient tolerability. While past studies have looked at different light sources and delivery methods, this study strives to provide equivalent PpIX-weighted light doses with the hypothesis that artificial light sources could be equally as effective as natural sunlight if their PpIX-weighted fluences were equalized. Normal mouse skin was used as the model to compare blue LED light, metal halide white light and natural sunlight, with minimal incubation time between topical ALA application and the onset of light delivery. A total PpIX-weighted fluence of 20 J eff cm -2 was delivered over 2 h, and the efficacy of response was quantified using three acute bioassays for PDT damage: PpIX photobleaching, Stat3 crosslinking and quantitative histopathology. These bioassays indicated blue light was slightly inferior to both sunlight and white light, but that the latter two were not significantly different. The results suggest that metal halide white light could be a reasonable alternative to daylight PDT, which should allow a more controlled treatment that is independent of weather and yet should have similar response rates with limited pain during treatment. © 2018 The American Society of Photobiology.
Global Variation of Meteor Trail Plasma Turbulence
NASA Technical Reports Server (NTRS)
Dyrud, L. P.; Hinrichs, J.; Urbina, J.
2011-01-01
We present the first global simulations on the occurrence of meteor trail plasma irregularities. These results seek to answer the following questions: when a meteoroid disintegrates in the atmosphere will the resulting trail become plasma turbulent, what are the factors influencing the development of turbulence, and how do they vary on a global scale. Understanding meteor trail plasma turbulence is important because turbulent meteor trails are visible as non-specular trails to coherent radars, and turbulence influences the evolution of specular radar meteor trails, particularly regarding the inference of mesospheric temperatures from trail diffusion rates, and their usage for meteor burst communication. We provide evidence of the significant effect that neutral atmospheric winds and density, and ionospheric plasma density have on the variability of meteor trail evolution and the observation of nonspecular meteor trails, and demonstrate that trails are far less likely to become and remain turbulent in daylight, explaining several observational trends using non-specular and specular meteor trails.
Energy Savings by Treating Buildings as Systems
NASA Astrophysics Data System (ADS)
Harvey, L. D. Danny
2008-09-01
This paper reviews the opportunities for dramatically reducing energy use in buildings by treating buildings as systems, rather than focusing on device efficiencies. Systems-level considerations are relevant for the operation of heat pumps (where the temperatures at which heat or coldness are distributed are particularly important); the joint or separate provision of heating, cooling, and ventilation; the joint or separate removal of sensible heat and moisture; and in the operation of fluid systems having pumps. Passive heating, cooling, and ventilation, as well as daylighting (use of sunlight for lighting purposes) also require consideration of buildings as systems. In order to achieve the significant (50-75%) energy savings that are possible through a systems approach, the design process itself has to involve a high degree of integration between the architect and various engineering disciplines (structural, mechanical, electrical), and requires the systematic examination and adjustment of alternative designs using computer simulation models.
Code of Federal Regulations, 2011 CFR
2011-01-01
... innovative designs, materials, and equipment such as daylighting, passive solar heating, and heat recovery... select the fuel source for the HVAC systems, service hot water, and process loads from available...
... or produced by the skin when exposed to sunlight. Lack of vitamin D production by the skin ... who: Live in climates with little exposure to sunlight Must stay indoors Work indoors during the daylight ...
New Trends in Educational Lighting Systems.
ERIC Educational Resources Information Center
Murphy, Peter
2001-01-01
Explores technological trends for improving campus lighting, including the use of direct-indirect suspended fluorescent lighting, suspended linear lighting, high-efficiency optical systems, and occupancy and daylight sensors. (GR)
76 FR 18467 - Pattern of Violations
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-04
... Eastern Daylight Savings Time on April 18, 2011. ADDRESSES: Submit comments by any of the following... proposed rule addressing Pattern of Violations (POV). This extension gives commenters additional time to...
... may use a variety of instruments, shine bright lights directly at your eyes and request that you ... exam is complete, as daylight or other bright lights may be uncomfortable or cause blurred vision. Also, ...
Hatamleh, Muhanad M; Watts, David C
2011-02-01
To evaluate the effect of three commonly used bond primers on the bending strength of glass fibers and their bond strength to maxillofacial silicone elastomer after 360 hours of accelerated daylight aging. Eighty specimens were fabricated by embedding resin-impregnated fiber bundles (1.5-mm diameter, 20-mm long) into maxillofacial silicone elastomer M511 (Cosmesil). Twenty fiber bundles served as control and did not receive surface treatment with primers, whereas the remaining 60 fibers were treated with three primers (n = 20): G611 (Principality Medical), A-304 (Factor II), and A-330-Gold (Factor II). Forty specimens were dry stored at room temperature (23 ± 1°C) for 24 hours, and the remaining specimens were aged using an environmental chamber under accelerated exposure to artificial daylight for 360 hours. The aging cycle included continuous exposure to quartz-filtered visible daylight (irradiance 760 W/m(2) ) under an alternating weathering cycle (wet for 18 minutes, dry for 102 minutes). Pull-out tests were performed to evaluate bond strength between fiber bundles and silicone using a universal testing machine at 1 mm/min crosshead speed. A 3-point bending test was performed to evaluate the bending strength of the fiber bundles. One-way Analysis of Variance (ANOVA), Bonferroni post hoc test, and an independent t-test were carried out to detect statistical significances (p < 0.05). Mean (SD) values of maximum pull-out forces (N) before aging for groups: no primer, G611, A-304, A-330-G were: 13.63 (7.45), 20.44 (2.99), 22.06 (6.69), and 57.91 (10.15), respectively. All primers increased bond strength in comparison to control specimens (p < 0.05). Primer A-330-G showed the greatest increase among all primers (p < 0.05); however, bonding degraded after aging (p < 0.05), and pull-out forces were 13.58 (2.61), 6.17 (2.89), 6.95 (2.61), and 11.72 (3.03). Maximum bending strengths of fiber bundles at baseline increased after treatment with primers and light aging in comparison with control specimens (p < 0.05), and were in the range of 917.72 to 1095.25 and 1124.06 to 1596.68 MPa at both baseline and after 360 hours aging (p < 0.05). The use of A-330-G primer in conjunction with silicone Cosmesil M511 produced the greatest bond strength for silicone-glass fiber surfaces at baseline; however, bond strength was significantly degraded after accelerated daylight aging. Treatment with primer and accelerated daylight aging increased bending strength of glass fibers. © 2011 by The American College of Prosthodontists.
Global MHD Modeling of Auroral Conjugacy for Different IMF Conditions
NASA Astrophysics Data System (ADS)
Hesse, M.; Kuznetsova, M. M.; Liu, Y. H.; Birn, J.; Rastaetter, L.
2016-12-01
The question whether auroral features are conjugate or not, and the search for the underlying scientific causes is of high interest in magnetospheric and ionospheric physics. Consequently, this topic has attracted considerable attention in space-based observations of auroral features, and it has inspired a number of theoretical ideas and related modeling activities. Potential contributing factors to the presence or absence of auroral conjugacy include precipitation asymmetries in case of the diffuse aurora, inter-hemispherical conductivity differences, magnetospheric asymmetries brought about by, e.g., dipole tilt, corotation, or IMF By, and, finally, asymmetries in field-aligned current generation primarily in the nightside magnetosphere. In this presentation, we will analyze high-resolution, global MHD simulations of magnetospheric dynamics, with emphasis on auroral conjugacy. For the purpose of this study, we define controlled conditions by selecting solstice times with steady solar wind input, the latter of which includes an IMF rotation from purely southward to east-westward. Conductivity models will include both auroral precipaition proxies as well as the effects of the aysmmetric daylight. We will analyze these simulations with respect to conjugacies or the lack thereof, and study the role of the effects above in determing the former.
Modelling the effects of stranding on the Atlantic salmon population in the Dale River, Norway.
Sauterleute, Julian F; Hedger, Richard D; Hauer, Christoph; Pulg, Ulrich; Skoglund, Helge; Sundt-Hansen, Line E; Bakken, Tor Haakon; Ugedal, Ola
2016-12-15
Rapid dewatering in rivers as a consequence of hydropower operations may cause stranding of juvenile fish and have a negative impact on fish populations. We implemented stranding into an Atlantic salmon population model in order to evaluate long-term effects on the population in the Dale River, Western Norway. Furthermore, we assessed the sensitivity of the stranding model to dewatered area in comparison to biological parameters, and compared different methods for calculating wetted area, the main abiotic input parameter to the population model. Five scenarios were simulated dependent on fish life-stage, season and light level. Our simulation results showed largest negative effect on the population abundance for hydropeaking during winter daylight. Salmon smolt production had highest sensitivity to the stranding mortality of older juvenile fish, suggesting that stranding of fish at these life-stages is likely to have greater population impacts than that of earlier life-stages. Downstream retention effects on the ramping velocity were found to be negligible in the stranding model, but are suggested to be important in the context of mitigation measure design. Copyright © 2016 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Filler, Martin
1979-01-01
The new energy consciousness has led to a thorough reevaluation of how artificial lighting can be used wisely, while other researchers have explored the potential of daylighting as an alternative interior light source. (Author/MLF)
Development of Shanghai satellite laser ranging station
NASA Technical Reports Server (NTRS)
Yang, Fu-Min; Tan, De-Tong; Xiao, Chi-Kun; Chen, Wan-Zhen; Zhang, J.-H.; Zhang, Z.-P.; Lu, Wen-Hu; Hu, Z.-Q.; Tang, W.-F.; Chen, J.-P.
1993-01-01
The topics covered include the following: improvement of the system hardware; upgrading of the software; the observation status; preliminary daylight tracking capability; testing the new type of laser; and future plans.
Adaptive spatial filtering for daytime satellite quantum key distribution
NASA Astrophysics Data System (ADS)
Gruneisen, Mark T.; Sickmiller, Brett A.; Flanagan, Michael B.; Black, James P.; Stoltenberg, Kurt E.; Duchane, Alexander W.
2014-11-01
The rate of secure key generation (SKG) in quantum key distribution (QKD) is adversely affected by optical noise and loss in the quantum channel. In a free-space atmospheric channel, the scattering of sunlight into the channel can lead to quantum bit error ratios (QBERs) sufficiently large to preclude SKG. Furthermore, atmospheric turbulence limits the degree to which spatial filtering can reduce sky noise without introducing signal losses. A system simulation quantifies the potential benefit of tracking and higher-order adaptive optics (AO) technologies to SKG rates in a daytime satellite engagement scenario. The simulations are performed assuming propagation from a low-Earth orbit (LEO) satellite to a terrestrial receiver that includes an AO system comprised of a Shack-Hartmann wave-front sensor (SHWFS) and a continuous-face-sheet deformable mirror (DM). The effects of atmospheric turbulence, tracking, and higher-order AO on the photon capture efficiency are simulated using statistical representations of turbulence and a time-domain waveoptics hardware emulator. Secure key generation rates are then calculated for the decoy state QKD protocol as a function of the receiver field of view (FOV) for various pointing angles. The results show that at FOVs smaller than previously considered, AO technologies can enhance SKG rates in daylight and even enable SKG where it would otherwise be prohibited as a consequence of either background optical noise or signal loss due to turbulence effects.
Qualitative issues in the evolution of the Andersen Lighthouse
DOE Office of Scientific and Technical Information (OSTI.GOV)
De Keyser, D.; Gratz, S.; Barton, S.A.
1995-11-01
This paper reports on the continuing product development of the Andersen Lighthouse. Refer to ``Development of the Andersen Lighthouse for the Wal-Mart Environmental Demonstration Store`` in the Solar `94 Conference Proceedings for a description of the Andersen Lighthouse. The goals for this project were to evaluate the following qualitative issues surrounding daylighting: color rendition, quality of light, view to the sky, and human perception. In order to evaluate the effects of the Andersen Lighthouse the authors compared it to a high transmission translucent (acrylic bubble) skylight and an ordinary translucent (acrylic bubble) skylight. In addition to the above comparison, amore » test installation of Andersen Lighthouses in a manufacturing space was analyzed. This case study covers the affect the introduction of natural light and view had on the comfort and productivity of the employees. Visual observations, illumination readings, and employee questionnaires were used for evaluation.« less
Adaptation of sleep and circadian rhythms to the Antarctic summer - A question of zeitgeber strength
NASA Technical Reports Server (NTRS)
Gander, Philippa H.; Macdonald, John A.; Montgomery, John C.; Paulin, Michael G.
1991-01-01
Adaptation of sleep and circadian rhythms was examined in three temperate zone dwellers arriving in Antarctica during summer. Rectal temperature, wrist activity, and heart rate were monitored continuously, sleep timing and quality noted on awakening, and mood and fatigue rated every 2 h while awake. Sleep was poorer in 2/3 subjects in Antarctica, where all subjects reported more difficulty rising. Sleep occurred at the same clock times in New Zealand and Antarctica, however, the rhythms of temperature, activity, and heart rate underwent a delay of about of 2 h. The subject with the most Antarctic experience had the least difficulty adapting to sleeping during constant daylight. The subject with the most delayed circadian rhythms had the most difficulty. The delay in the circadian system with respect to sleep and clock time is hypothesized to be due to differences in zeitgeber strength and/or zeitgeber exposure between Antarctica and New Zealand.
In Search of a Good Night's Sleep.
Leahy, Laura G
2017-10-01
A good night's sleep is essential to overall physical, cognitive, and emotional well-being. Sleep deprivation, whether general or related to time changes (e.g., daylight saving time), contributes to decreased cognition, impaired memory, poor coordination, mood fluctuations, increased risk of heart disease and diabetes, and weight gain, among others. The sleep cycle is defined by five stages and two distinct parts-rapid eye movement (REM) and non-REM sleep-that work to promote not only the quantity of sleep but also the quality of sleep, which impacts overall health. Each stage of sleep is influenced by various neurochemical actions among the brain regions. The neurochemistry and neuropath-ways related to the sleep/wake cycle as well as the mechanisms of action of sleep-inducing and wake-promoting medications are explored. [Journal of Psychosocial Nursing and Mental Health Services, 55(10), 19-26.]. Copyright 2017, SLACK Incorporated.
31 CFR 588.302 - Effective date.
Code of Federal Regulations, 2010 CFR
2010-07-01
... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY WESTERN BALKANS STABILIZATION REGULATIONS General... interests in property are blocked pursuant to § 588.201(a)(1), 12:01 a.m. eastern daylight time, June 27...
14 CFR 103.11 - Daylight operations.
Code of Federal Regulations, 2010 CFR
2010-01-01
...) Notwithstanding paragraph (a) of this section, ultralight vehicles may be operated during the twilight periods 30... civil twilight as defined in the Air Almanac, if: (1) The vehicle is equipped with an operating...
... light signal is low, the hypothalamus tells the pineal gland, a small organ situated in the brain, to ... During daylight hours, the opposite occurs, and the pineal gland produces very little melatonin. You may be able ...
34 CFR 101.33 - Filing and service.
Code of Federal Regulations, 2010 CFR
2010-07-01
.... to 5:30 p.m., eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time. Originals only on exhibits and transcripts of testimony need be filed. For...
ERIC Educational Resources Information Center
Raloff, Janet
1978-01-01
Presented are different research program developments aimed at reducing the consumption of electrical energy for artificial lights. Explains the idea of the dimmers, where the amount of incoming daylight regulates the current needed for the lamp. (GA)
34 CFR 101.33 - Filing and service.
Code of Federal Regulations, 2012 CFR
2012-07-01
.... to 5:30 p.m., eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time. Originals only on exhibits and transcripts of testimony need be filed. For...
34 CFR 101.33 - Filing and service.
Code of Federal Regulations, 2011 CFR
2011-07-01
.... to 5:30 p.m., eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time. Originals only on exhibits and transcripts of testimony need be filed. For...
34 CFR 101.33 - Filing and service.
Code of Federal Regulations, 2013 CFR
2013-07-01
.... to 5:30 p.m., eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time. Originals only on exhibits and transcripts of testimony need be filed. For...
34 CFR 101.33 - Filing and service.
Code of Federal Regulations, 2014 CFR
2014-07-01
.... to 5:30 p.m., eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time. Originals only on exhibits and transcripts of testimony need be filed. For...
NASA Technical Reports Server (NTRS)
Hirschberg, J. G.
1979-01-01
Proposed monitor that detects back-reflected infrared radiation makes in situ turbidity measurements of lakes, streams, and other bodies of water. Monitor is compact, works well in daylight as at night, and is easily operated in rough seas.
Biogeography of time partitioning in mammals.
Bennie, Jonathan J; Duffy, James P; Inger, Richard; Gaston, Kevin J
2014-09-23
Many animals regulate their activity over a 24-h sleep-wake cycle, concentrating their peak periods of activity to coincide with the hours of daylight, darkness, or twilight, or using different periods of light and darkness in more complex ways. These behavioral differences, which are in themselves functional traits, are associated with suites of physiological and morphological adaptations with implications for the ecological roles of species. The biogeography of diel time partitioning is, however, poorly understood. Here, we document basic biogeographic patterns of time partitioning by mammals and ecologically relevant large-scale patterns of natural variation in "illuminated activity time" constrained by temperature, and we determine how well the first of these are predicted by the second. Although the majority of mammals are nocturnal, the distributions of diurnal and crepuscular species richness are strongly associated with the availability of biologically useful daylight and twilight, respectively. Cathemerality is associated with relatively long hours of daylight and twilight in the northern Holarctic region, whereas the proportion of nocturnal species is highest in arid regions and lowest at extreme high altitudes. Although thermal constraints on activity have been identified as key to the distributions of organisms, constraints due to functional adaptation to the light environment are less well studied. Global patterns in diversity are constrained by the availability of the temporal niche; disruption of these constraints by the spread of artificial lighting and anthropogenic climate change, and the potential effects on time partitioning, are likely to be critical influences on species' future distributions.
Gellerfors, Mikael; Svensén, Christer; Linde, Joacim; Lossius, Hans Morten; Gryth, Dan
2015-09-01
Securing the airway by endotracheal intubation (ETI) is a key issue in prehospital critical care. Night vision goggles (NVG) are used by personnel operating in low-light environments. We examined the feasibility of an anesthesiologist performed ETI using NVG in a helicopter setting. Twelve anesthesiologists performed ETI on a manikin in an emergency room (ER) setting and two helicopter settings, with randomization to either rotary wing daylight (RW-D) or rotary wing in total darkness using binocular NVG (RW-NVG). Primary endpoint was intubation time. Secondary endpoints included success rate, Cormack-Lehane (CL) score, and subjective difficulty according to the Visual Analoge Scale (VAS). The median intubation time was shorter for the RW-D compared to the RW-NVG setting (16.5 seconds vs. 30.0 seconds; p = 0,03). We found no difference in median intubation time for the ER and RW-D settings (16.8 seconds vs. 16.5 seconds; p = 0.91). For all scenarios, success rate was 100%. CL and VAS varied between the ER setting (CL 1.8, VAS 2.8), RW-D setting (CL 2.0, VAS 3.0), and RW-NVG setting (CL 3.0, VAS 6.5). This study suggests that anesthesiologists successfully and quickly can perform ETI in a helicopter setting both in daylight and in darkness using binocular NVG, but with shorter intubation times in daylight. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.
High Performance Building Facade Solutions - PIER Final Project Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Eleanor; Selkowitz, Stephen
2009-12-31
Building facades directly influence heating and cooling loads and indirectly influence lighting loads when daylighting is considered, and are therefore a major determinant of annual energy use and peak electric demand. Facades also significantly influence occupant comfort and satisfaction, making the design optimization challenge more complex than many other building systems.This work focused on addressing significant near-term opportunities to reduce energy use in California commercial building stock by a) targeting voluntary, design-based opportunities derived from the use of better design guidelines and tools, and b) developing and deploying more efficient glazings, shading systems, daylighting systems, facade systems and integrated controls.more » This two-year project, supported by the California Energy Commission PIER program and the US Department of Energy, initiated a collaborative effort between The Lawrence Berkeley National Laboratory (LBNL) and major stakeholders in the facades industry to develop, evaluate, and accelerate market deployment of emerging, high-performance, integrated facade solutions. The LBNL Windows Testbed Facility acted as the primary catalyst and mediator on both sides of the building industry supply-user business transaction by a) aiding component suppliers to create and optimize cost effective, integrated systems that work, and b) demonstrating and verifying to the owner, designer, and specifier community that these integrated systems reliably deliver required energy performance. An industry consortium was initiated amongst approximately seventy disparate stakeholders, who unlike the HVAC or lighting industry, has no single representative, multi-disciplinary body or organized means of communicating and collaborating. The consortium provided guidance on the project and more importantly, began to mutually work out and agree on the goals, criteria, and pathways needed to attain the ambitious net zero energy goals defined by California and the US.A collaborative test, monitoring, and reporting protocol was also formulated via the Windows Testbed Facility in collaboration with industry partners, transitioning industry to focus on the importance of expecting measured performance to consistently achieve design performance expectations. The facility enables accurate quantification of energy use, peak demand, and occupant comfort impacts of synergistic facade-lighting-HVAC systems on an apples-to-apples comparative basis and its data can be used to verify results from simulations. Emerging interior and exterior shading technologies were investigated as potential near-term, low-cost solutions with potential broad applicability in both new and retrofit construction. Commercially-available and prototype technologies were developed, tested, and evaluated. Full-scale, monitored field tests were conducted over solstice-to-solstice periods to thoroughly evaluate the technologies, uncover potential risks associated with an unknown, and quantify performance benefits. Exterior shading systems were found to yield net zero energy levels of performance in a sunny climate and significant reductions in summer peak demand. Automated interior shading systems were found to yield significant daylighting and comfort-related benefits.In support of an integrated design process, a PC-based commercial fenestration (COMFEN) software package, based on EnergyPlus, was developed that enables architects and engineers to quickly assess and compare the performance of innovative facade technologies in the early sketch or schematic design phase. This tool is publicly available for free and will continue to improve in terms of features and accuracy. Other work was conducted to develop simulation tools to model the performance of any arbitrary complex fenestration system such as common Venetian blinds, fabric roller shades as well as more exotic innovative facade systems such as optical louver systems.« less
ERIC Educational Resources Information Center
Walker, Jearl
1989-01-01
Explains the color change of the sky by using scattering with science history. Provides several diagrams in each case, such as daylight, twilight, just after sunset, setting sun, and earth's shadow. Presents a reference of three further reading materials. (YP)
2005-07-18
Typhoon Haitang is shown here churning steadily towards Taiwan and China. This image shows the storm swirling wind patterns as observed by NASA QuikScat satellite on July 14, 2005, at 19:19 UTC 14:19 Eastern Daylight Time.
17 CFR 171.3 - Business address; hours.
Code of Federal Regulations, 2014 CFR
2014-04-01
.... until 4:45 p.m., eastern standard time or eastern daylight savings time, whichever is currently in effect in Washington, DC. [55 FR 41068, Oct. 9, 1990, as amended at 60 FR 49336, Sept. 25, 1995] ...
Atmospheric Science Data Center
2014-09-25
Solar Noon (GMT time) The time when the sun is due south in the northern hemisphere or due north in the southern ... The average cosine of the angle between the sun and directly overhead during daylight hours. Cosine solar ...
Data and Tools | Integrated Energy Solutions | NREL
for a research campus eQUEST. Detailed analysis of today's state-of-the-art building design source software tools to support whole building energy modeling and advanced daylight analysis BESTEST-EX
Overhead guide sign retroreflectivity and illumination : [technical summary].
DOT National Transportation Integrated Search
2015-01-01
Compared to daylight driving, nighttime driving is more demanding because of visibility : issues, such as a drivers visual acuity, contrast sensitivity, distance judgment, and : color discrimination. Overhead highway signs are very important for e...
Torsional Buckling Tests of a Simulated Solar Array
NASA Technical Reports Server (NTRS)
Thornton, E. A.
1996-01-01
Spacecraft solar arrays are typically large structures supported by long, thin deployable booms. As such, they may be particularly susceptible to abnormal structural behavior induced by mechanical and thermal loading. One example is the Hubble Space Telescope solar arrays which consist of two split tubes fit one inside the other called BiSTEMs. The original solar arrays on the Hubble Space Telescope were found to be severely twisted following deployment and later telemetry data showed the arrays were vibrating during daylight to night and night to daylight transition. The solar array twist however can force the BiSTEM booms to change in cross-section and cause tile solar arrays to react unpredictably to future loading. The solar arrays were redesigned to correct for tile vibration, however, upon redeployment they again twisted. To assess the influence of boom cross-sectional configuration, experiments were conducted on two types of booms, (1)booms with closed cross-sections, and (2) booms with open cross-sections. Both models were subjected to compressive loading and imposed tip deflections. An existing analytical model by Chung and Thornton was used to define the individual load ranges for each model solar array configuration. The load range for the model solar array using closed cross-section booms was 0-120 Newtons and 0-160 Newtons for the model solar array using open cross-section booms. The results indicate the model solar array with closed cross-section booms buckled only in flexure. However, the results of the experiment with open cross-section booms indicate the model solar array buckled only in torsion and with imposed tip deflections the cross section can degrade by rotation of the inner relative to the outer STEM. For tile Hubble Space Telescope solar arrays the results of these experiments indicate the twisting resulted from the initial mechanical loading of the open cross-section booms.
Demonstration of obstacle avoidance system (OASYS) symbology in full mission simulation
NASA Astrophysics Data System (ADS)
Sharkey, Thomas J.
1994-06-01
The U. S. Army Aeroflightdynamics Directorate's (AFDD) Crew Station Research and Development Branch (CSRDB) conducted a multiphase effort to develop symbology displaying information from the Obstacle Avoidance System (OASYS) on the Aviator's Night Vision System (ANVIS) Head Up Display (HUD). The first phase of this program used static symbology displayed on a workstation to identify the types of information required from OASYS by the pilot. The second phase used a low-fidelity, pilot-in-the-loop simulation to evaluate fourteen different symbology-drive law combinations. Based on the results of phases 1 and 2 three candidate symbologies were selected, along with the baseline symbology developed by the OASYS contractor, for evaluation in full mission simulation. In addition, a full-daylight, full field-of-view condition and Night Vision Goggle (NVG) condition, both without OASYS symbology, were used as control conditions. The environmental conditions (e.g., ambient illumination, visual range) and task requirements (e.g., altitude and airspeed) used in the simulation were selected to severely tax the symbology. Reliable differences in performance between symbology conditions were found. Two of the symbologies developed during the earlier phases of this program resulted in reduced frequencies of ground strikes compared to OASYS baseline and NVG only conditions. The frequency of close approaches to wires was lower with the symbology developed in this program than with the baseline symbology. All OASYS symbologies improved performance relative to the NVG control condition. It is recommended that the OASYS symbology and drive laws developed during this program be used during OASYS flight tests.
31 CFR 588.205 - Expenses of maintaining blocked property; liquidation of blocked account.
Code of Federal Regulations, 2010 CFR
2010-07-01
... WESTERN BALKANS STABILIZATION REGULATIONS Prohibitions § 588.205 Expenses of maintaining blocked property... license or permit granted before 12:01 a.m., eastern daylight time, June 27, 2001, all expenses incident...
2011-07-22
This computer-generated view depicts part of Mars at the boundary between darkness and daylight, with an area including Gale Crater beginning to catch morning light. NASA has selected Gale as the landing site for the Mars Science Laboratory mission.
21 CFR 1316.45 - Filings; address; hours.
Code of Federal Regulations, 2014 CFR
2014-04-01
... through Friday from 8:30 a.m. to 5 p.m. eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time, except on national legal holidays. Documents shall be dated...
21 CFR 1316.45 - Filings; address; hours.
Code of Federal Regulations, 2012 CFR
2012-04-01
... through Friday from 8:30 a.m. to 5 p.m. eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time, except on national legal holidays. Documents shall be dated...
21 CFR 1316.45 - Filings; address; hours.
Code of Federal Regulations, 2011 CFR
2011-04-01
... through Friday from 8:30 a.m. to 5 p.m. eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time, except on national legal holidays. Documents shall be dated...
21 CFR 1316.45 - Filings; address; hours.
Code of Federal Regulations, 2013 CFR
2013-04-01
... through Friday from 8:30 a.m. to 5 p.m. eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time, except on national legal holidays. Documents shall be dated...
12 CFR 11.3 - Filing requirements and inspection of documents.
Code of Federal Regulations, 2012 CFR
2012-01-01
... submitted by direct transmission on or before 10 p.m. Eastern Standard Time or Eastern Daylight Savings Time, whichever is currently in effect, shall be deemed filed on the same business day. (4) Mandatory compliance...
12 CFR 11.3 - Filing requirements and inspection of documents.
Code of Federal Regulations, 2011 CFR
2011-01-01
... submitted by direct transmission on or before 10 p.m. Eastern Standard Time or Eastern Daylight Savings Time, whichever is currently in effect, shall be deemed filed on the same business day. (4) Mandatory compliance...
12 CFR 11.3 - Filing requirements and inspection of documents.
Code of Federal Regulations, 2014 CFR
2014-01-01
... submitted by direct transmission on or before 10 p.m. Eastern Standard Time or Eastern Daylight Savings Time, whichever is currently in effect, shall be deemed filed on the same business day. (4) Mandatory compliance...
12 CFR 11.3 - Filing requirements and inspection of documents.
Code of Federal Regulations, 2013 CFR
2013-01-01
... submitted by direct transmission on or before 10 p.m. Eastern Standard Time or Eastern Daylight Savings Time, whichever is currently in effect, shall be deemed filed on the same business day. (4) Mandatory compliance...
75 FR 14131 - Broadband Technology Opportunities Program
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-24
... DEPARTMENT OF COMMERCE National Telecommunications and Information Administration [Docket Number: 0907141137-0154-09] RIN 0660-ZA28 Broadband Technology Opportunities Program AGENCY: National... under the Broadband Technology Opportunities Program (BTOP) is extended until 10 p.m. Eastern Daylight...
Optimal Implementations for Reliable Circadian Clocks
NASA Astrophysics Data System (ADS)
Hasegawa, Yoshihiko; Arita, Masanori
2014-09-01
Circadian rhythms are acquired through evolution to increase the chances for survival through synchronizing with the daylight cycle. Reliable synchronization is realized through two trade-off properties: regularity to keep time precisely, and entrainability to synchronize the internal time with daylight. We find by using a phase model with multiple inputs that achieving the maximal limit of regularity and entrainability entails many inherent features of the circadian mechanism. At the molecular level, we demonstrate the role sharing of two light inputs, phase advance and delay, as is well observed in mammals. At the behavioral level, the optimal phase-response curve inevitably contains a dead zone, a time during which light pulses neither advance nor delay the clock. We reproduce the results of phase-controlling experiments entrained by two types of periodic light pulses. Our results indicate that circadian clocks are designed optimally for reliable clockwork through evolution.
Seasonality of suicides: environmental, sociological and biological covariations.
Souêtre, E; Salvati, E; Belugou, J L; Douillet, P; Braccini, T; Darcourt, G
1987-01-01
The monthly rates of completed suicides in France from 1978 until 1982 were analyzed. The seasonal variations of environmental (daylight and sunlight durations, mean temperature, geomagnetism), sociological (unemployment, deaths of all causes, birth and conception rates), and biological (melatonin, cortisol and serotonin circannual rhythms) factors were compared to the seasonal patterns of suicides. A clear seasonal variation (with peaks in May and September) in suicidal behavior was detected. These patterns tended to differ as a function of age (bimodal in young, unimodal in old people). The component analysis clearly pointed out that seasonal patterns of suicides may be considered as the sum of two components, unimodal and bimodal. Almost similar covariations were found between the main seasonal (unimodal) component of suicides and environmental (daylight duration and mean monthly temperature) or sociological factors whereas the secondary component was more correlated to variations in environmental factors and, to some extent, to biological parameters.
De Leonibus, C; Chatelain, P; Knight, C; Clayton, P; Stevens, A
2016-11-01
The response to growth hormone in humans is dependent on phenotypic, genetic and environmental factors. The present study in children with growth hormone deficiency (GHD) collected worldwide characterised gene-environment interactions on growth response to recombinant human growth hormone (r-hGH). Growth responses in children are linked to latitude, and we found that a correlate of latitude, summer daylight exposure (SDE), was a key environmental factor related to growth response to r-hGH. In turn growth response was determined by an interaction between both SDE and genes known to affect growth response to r-hGH. In addition, analysis of associated networks of gene expression implicated a role for circadian clock pathways and specifically the developmental transcription factor NANOG. This work provides the first observation of gene-environment interactions in children treated with r-hGH.
De Leonibus, C; Chatelain, P; Knight, C; Clayton, P; Stevens, A
2016-01-01
The response to growth hormone in humans is dependent on phenotypic, genetic and environmental factors. The present study in children with growth hormone deficiency (GHD) collected worldwide characterised gene–environment interactions on growth response to recombinant human growth hormone (r-hGH). Growth responses in children are linked to latitude, and we found that a correlate of latitude, summer daylight exposure (SDE), was a key environmental factor related to growth response to r-hGH. In turn growth response was determined by an interaction between both SDE and genes known to affect growth response to r-hGH. In addition, analysis of associated networks of gene expression implicated a role for circadian clock pathways and specifically the developmental transcription factor NANOG. This work provides the first observation of gene–environment interactions in children treated with r-hGH. PMID:26503811
NASA Technical Reports Server (NTRS)
Weinstein, S.; Pane, D.; Warren-Rhodes, K.; Cockell, C.; Ernst, L. A.; Minkley, E.; Fisher, G.; Emani, S.; Wettergreen, D. S.; Wagner, M.
2005-01-01
We have developed an imaging system, the Fluorescence Imager (FI), for detecting fluorescence signals from sparse microorganisms and biofilms during autonomous rover exploration. The fluorescence signals arise both from naturally occurring chromophores, such as chlorophyll of cyanobacteria and lichens, and from fluorescent probes applied to soil and rocks. Daylight imaging has been accomplished by a novel use of a high-powered flashlamp synchronized to a CCD camera. The fluorescent probes are cell permanent stains that have extremely low intrinsic fluorescence (quantum yields less than 0.01) and a large fluorescence enhancement (quantum yields greater than 0.4) when bound to the target. Each probe specifically targets either carbohydrates, proteins, nucleic acids or membrane lipids, the four classes of macromolecules found in terrestrial life. The intent of the probes is to interrogate the environment for surface and endolithic life forms.
NASA Technical Reports Server (NTRS)
Comiso, Josefino C.; Perovich, Don; Stamnes, Knut; Stuart, Venetia (Editor)
2015-01-01
The polar regions are places of extremes. There are months when the regions are enveloped in unending darkness, and months when they are in continuous daylight. During the daylight months the sun is low on the horizon and often obscured by clouds. In the dark winter months temperatures are brutally cold, and high winds and blowing snow are common. Even in summer, temperatures seldom rise above 0degC. The cold winter temperatures cause the ocean to freeze, forming sea ice. This sea ice cover acts as a barrier limiting the transfer of heat, moisture, and momentum between the atmosphere and the ocean. It also greatly complicates the optical signature of the surface. Taken together, these factors make the polar regions a highly challenging environment for optical remote sensing of the ocean.
[Indoor air quality in school facilities in Cassino (Italy)].
Langiano, Elisa; Lanni, Liana; Atrei, Patrizia; Ferrara, Maria; La Torre, Giuseppe; Capelli, Giovanni; De Vito, Elisabetta
2008-01-01
This study evaluated the indoor air quality of 26 classrooms of secondary schools in the city of Cassino (Italy). Two types of school buildings were assessed: buildings specifically designed as schools, and former dwellings converted to schools. Measurements were taken in both winter and spring months, before students entered the classrooms and while the classrooms were occupied. Lower thermal comfort levels were observed during the winter months; in fact, during the winter, ideal temperature, humidity and air speed parameters were found in only a small percentage of classrooms and students were found to experience thermal discomfort as a result. Air velocity was often found to be inadequate both in winter and spring months and in both types of school buildings evaluated. Illumination levels measured during the winter months with both natural daylight and mixed illumination, were found to be below 200 lux, the minimum recommended level recommended by the ministerial decree 18.12.1975. Noise levels above the maximum level recommended by the ministerial decree 01.03.1991 were also frequently observed. The symptoms most frequently reported by students were headache, difficulties in concentrating, cough, and unusual tiredness. The various discomfort situations observed in both types of school buildings point toward a need for greater attention toward indoor air quality of schools as this can have affect students' attention, concentration, productivity and comfort.
Twilight far-red treatment advances leaf bud burst of silver birch (Betula pendula).
Linkosalo, Tapio; Lechowicz, Martin J
2006-10-01
Bud development of boreal trees in spring, once initiated, is driven by ambient air temperature, but the mechanism triggering bud development remains unclear. We determined if some aspect of the diurnal or seasonal light regime influences initiation of bud burst once the chilling requirement is met. We grew 3-year-old birch plantlets cloned from a mature tree of boreal origin in light conditions realistically simulating the lengthening days of spring at 60 degrees N. To emulate the reduction in red to far-red light (R:FR) ratio between daylight and twilight, one group of plantlets was subjected to reduced R:FR ratio in the morning and evening in addition to progressively lengthening days, whereas the other group was subjected to the same R:FR ratio throughout the day. The reduced R:FR ratio of twilight advanced bud burst by 4 days compared with the reference group (P = 0.04). To assess the interplay between the fulfillment of the chilling requirement and the subsequent response to warming, we fitted a thermal time model to the data with separate parameterizations for the starting dates of heat sum accumulation in each treatment. Least-squares fitting suggested that bud development started in light regimes corresponding to late March, almost two months after the chilling requirement for dormancy release was satisfied. Therefore, shortening night length or increasing day length, or both, appears to be the cue enabling bud development in spring, with twilight quality having an effect on the photoperiodic response. If twilight alone were the cue, the difference in bud burst dates between the experimental groups would have been greater than 4 days. The result gives experimental support for the use of thermal-time models in phenological modeling.
Nutritional factors affecting poultry bone health.
Fleming, Robert H
2008-05-01
Outlined are two main current research concerns relating to skeletal disorders in poultry: (a) osteoporosis in egg-laying hens; (b) leg problems caused by rapid bone growth in broiler chickens. Surveys indicate that 30% of caged laying hens suffer at least one lifetime fracture (a severe welfare issue). Modern hybrids produce one egg per d for 50 weeks. For this period 'normal' bone turnover ceases; only medullary bone (MB) is formed, a woven bone type of limited structural value. MB is resorbed for eggshell formation alongside structural bone, leading to increased fracture risk. Avian osteoporosis is reduced by activity and genetic selection but nutrition is also important. Fluoride and vitamin K are beneficial but the timing of nutritional intervention is important. Ca, inorganic P and vitamin D must be adequate and the form of Ca is critical. Limestone fed as particulates benefits skeletal and eggshell quality. In hens fed particulate limestone compared with flour-fed hens the tibiotarsus breaking strength and radiographic density are increased at 56 weeks of age (P<0.01 and P<0.001 respectively) and the number of tartrate-resistant acid phosphatase-positive stained active osteoclasts (mean number per microscopic field) is decreased (P<0.001). In broiler (meat) chickens selection for rapid growth from approximately 50 g to 3 kg in 42 d has inadvertently produced skeletal disorders such as tibial dyschondroplasia, rickets and associated valgus-varus deformities leading to lameness. The beneficial skeletal effects during growth of increased dietary n-3 PUFA:n-6 PUFA (utilising salmon oil) have been demonstrated. Experiments simulating daylight UVB levels have produced beneficial skeletal effects in Ca- and vitamin D-deficient chicks.
Concept of electro-optical sensor module for sniper detection system
NASA Astrophysics Data System (ADS)
Trzaskawka, Piotr; Dulski, Rafal; Kastek, Mariusz
2010-10-01
The paper presents an initial concept of the electro-optical sensor unit for sniper detection purposes. This unit, comprising of thermal and daylight cameras, can operate as a standalone device but its primary application is a multi-sensor sniper and shot detection system. Being a part of a larger system it should contribute to greater overall system efficiency and lower false alarm rate thanks to data and sensor fusion techniques. Additionally, it is expected to provide some pre-shot detection capabilities. Generally acoustic (or radar) systems used for shot detection offer only "after-the-shot" information and they cannot prevent enemy attack, which in case of a skilled sniper opponent usually means trouble. The passive imaging sensors presented in this paper, together with active systems detecting pointed optics, are capable of detecting specific shooter signatures or at least the presence of suspected objects in the vicinity. The proposed sensor unit use thermal camera as a primary sniper and shot detection tool. The basic camera parameters such as focal plane array size and type, focal length and aperture were chosen on the basis of assumed tactical characteristics of the system (mainly detection range) and current technology level. In order to provide costeffective solution the commercially available daylight camera modules and infrared focal plane arrays were tested, including fast cooled infrared array modules capable of 1000 fps image acquisition rate. The daylight camera operates as a support, providing corresponding visual image, easier to comprehend for a human operator. The initial assumptions concerning sensor operation were verified during laboratory and field test and some example shot recording sequences are presented.
Impact of daylight saving time on road traffic collision risk: a systematic review
Carey, Rachel N; Sarma, Kiran M
2017-01-01
Background Bills have been put forward in the UK and Republic of Ireland proposing a move to Central European Time (CET). Proponents argue that such a change will have benefits for road safety, with daylight being shifted from the morning, when collision risk is lower, to the evening, when risk is higher. Studies examining the impact of daylight saving time (DST) on road traffic collision risk can help inform the debate on the potential road safety benefits of a move to CET. The objective of this systematic review was to examine the impact of DST on collision risk. Methods Major electronic databases were searched, with no restrictions as to date of publication (the last search was performed in January 2017). Access to unpublished reports was requested through an international expert group. Studies that provided a quantitative analysis of the effect of DST on road safety-related outcomes were included. The primary outcomes of interest were road traffic collisions, injuries and fatalities. Findings Twenty-four studies met the inclusion criteria. Seventeen examined the short-term impact of transitions around DST and 12 examined long-term effects. Findings from the short-term studies were inconsistent. The long-term findings suggested a positive effect of DST. However, this cannot be attributed solely to DST, as a range of road collision risk factors vary over time. Interpretation The evidence from this review cannot support or refute the assertion that a permanent shift in light from morning to evening will have a road safety benefit. PMID:28674131
Lagrèze, Wolf A; Schaeffel, Frank
2017-09-04
Nearsightedness (myopia) has become more common around the world recently, mainly because of changes in visual, educational, and recreational behavior. The question arises how the risk of myopia and its progression can be reduced. This would lessen the prevalence and severity of myopia and also lower the risk of secondary diseases that impair visual acuity. The PubMed/Medline database was selectively searched for pertinent literature. The risk of myopia is lowered by exposure to daylight and increased by activities performed at short visual distances (close-up work). A person with little exposure to daylight has a fivefold risk of developing myopia, which can rise as high as a 16-fold risk if that person also performs close-up work. Two meta-analyses and a large randomized clinical trial from Asia have shown that the progression of myopia over two years of observation can be lessened by up to 0.71 diopters by the administration of atropine eye drops in a concentration that has practically no serious side effects. At higher doses, myopia progresses more severely than in the placebo group after the cessation of therapy. This is an off-label treatment. A weaker effect on progression has been shown for multifocal optical corrections that include both a distance correction and a correction for near vision. Effective pharmacological and optical measures are now available to lessen the progression of myopia. The increasing prevalence of myopia should motivate pediatricians, parents, and schools to pay attention to risk factors such as close-up work and lack of daylight exposure, particularly in view of the increased use of digital media.
Santi, Daniele; Magnani, Elisa; Michelangeli, Marco; Grassi, Roberto; Vecchi, Barbara; Pedroni, Gioia; Roli, Laura; De Santis, Maria Cristina; Baraldi, Enrica; Setti, Monica; Trenti, Tommaso; Simoni, Manuela
2018-04-01
Male fertility is progressively declining in many developed countries, but the relationship between male infertility and environmental factors is still unclear. To assess the influence of environmental temperature and air pollution on semen parameters, using a big-data approach. A big data analysis of parameters related to 5131 men, living in a province of Northern Italy and undergoing semen analyses between January 2010 and March 2016 was performed. Ambient temperature was recorded on the day of analysis and the 90 days prior to the analysis and the average value of particulate matter (PM) and NO2 in the year of the test. All data were acquired by geocoding patients residential address. A data warehouse containing 990,904,591 data was generated and analysed by multiple regressions. 5573 semen analyses were collected. Both maximum and minimum temperatures registered on the day of collection were inversely related to total sperm number (p < .001), non-progressive motility (NPrM) (p < .005) and normal forms (p < .001). Results were confirmed considering temperature in the 30 and 60 days before collection, but not in the 90 days before collection. Total sperm number was lower in summer/autumn (p < .001) and was inversely related with daylight duration (p < .001). PM10 and PM2.5 were inversely related to PrM (p < .001 and p < .005) and abnormal forms (p < .001). This is the first evaluation of the relationship between male fertility-related parameters and environment using a big-data approach. A seasonal change in semen parameters was found, with a fluctuation related to both temperature and daylight duration. A negative correlation between air pollution and semen quality is suggested. Such seasonal and environmental associations should be considered when assessing changes of male fertility-related parameters over time. Copyright © 2018 Elsevier Ltd. All rights reserved.
A thesis investigating the impact of energy related environmental factors on domestic window design
NASA Astrophysics Data System (ADS)
McEvoy, Michael Edward
In recent years the extent of glazing in houses has been tightly controlled by the Building Regulations in order to save energy. In addition guidelines derived from passive solar principles prescribe the distribution of domestic windows between elevations according to their orientation. This thesis studies the impact of these energy-related environmental factors on domestic window design. The first of these investigations determined the degree to which limitations on the area and arrangement of windows are significant in terms of daylighting. The experiments measured the effect that passive solar requirements and detailed aspects of window design have on the quality of daylighting in houses. The volume of background ventilation required for domestic accommodation has recently been increased. As a result, in a well-sealed construction, heat loss due to background ventilation becomes a larger part of the total heat loss and larger air movements become a potential cause of draughts. The ventilation experiment sought to establish the impact of these more onerous requirements on comfort within rooms. The third experiment combines these factors and asks the question: Could windows be actively involved in overcoming some of these difficulties by being used to preheat ventilation air in order to diminish the extent of heat loss and to alleviate the problem of cold draughts? Also by designing the window to reclaim heat from the room might it be possible to offset the window's thermal inadequacy? Through analysis of responses to a questionnaire and the use of optimisation techniques, scenarios were suggested for the future modification of windows in relation to energy and health expectations. The conclusions form a commentary on recent and future revisions to the Building Regulations and determine whether or not the Regulations facilitate the environmental engineering of windows as an active component of a building's whole environmental system.
ERIC Educational Resources Information Center
Scherer, Jeffrey
1999-01-01
Addresses how to integrate various types of light within the context of library design. Discusses light basics; the light spectrum; light measurement; reflectance; glare and brightness ratio; daylighting; electric lighting; and computer screens and lighting. Includes a checklist for plan review. (Author/LRW)
36 CFR 1150.23 - Filing and service.
Code of Federal Regulations, 2010 CFR
2010-07-01
... legal holidays excepted) from 9 a.m. to 5:30 p.m. Standard or Daylight Savings Time, whichever is effective in the city where the office of the judge is located at the time. (c) Service. Service of one copy...
38 CFR 18b.22 - Filing and service.
Code of Federal Regulations, 2010 CFR
2010-07-01
... excepted) from 8 a.m. to 4:30 p.m., eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time. Originals only of exhibits and transcripts of testimony need be filed...
ERIC Educational Resources Information Center
Maniccia, Dorine
2003-01-01
Explains that by using sustainable (green) building practices, schools and universities can make their lighting systems more efficient, noting that embracing green design principles can help schools attract students. Discusses lighting-control technologies (occupancy sensing technology, daylighting technology, and scheduling based technologies),…
38 CFR 18b.22 - Filing and service.
Code of Federal Regulations, 2014 CFR
2014-07-01
... excepted) from 8 a.m. to 4:30 p.m., eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time. Originals only of exhibits and transcripts of testimony need be filed...
38 CFR 18b.22 - Filing and service.
Code of Federal Regulations, 2013 CFR
2013-07-01
... excepted) from 8 a.m. to 4:30 p.m., eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time. Originals only of exhibits and transcripts of testimony need be filed...
36 CFR 1150.23 - Filing and service.
Code of Federal Regulations, 2012 CFR
2012-07-01
... legal holidays excepted) from 9 a.m. to 5:30 p.m. Standard or Daylight Savings Time, whichever is effective in the city where the office of the judge is located at the time. (c) Service. Service of one copy...
36 CFR 1150.23 - Filing and service.
Code of Federal Regulations, 2011 CFR
2011-07-01
... legal holidays excepted) from 9 a.m. to 5:30 p.m. Standard or Daylight Savings Time, whichever is effective in the city where the office of the judge is located at the time. (c) Service. Service of one copy...
38 CFR 18b.22 - Filing and service.
Code of Federal Regulations, 2011 CFR
2011-07-01
... excepted) from 8 a.m. to 4:30 p.m., eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time. Originals only of exhibits and transcripts of testimony need be filed...
38 CFR 18b.22 - Filing and service.
Code of Federal Regulations, 2012 CFR
2012-07-01
... excepted) from 8 a.m. to 4:30 p.m., eastern standard or daylight saving time, whichever is effective in the District of Columbia at the time. Originals only of exhibits and transcripts of testimony need be filed...
36 CFR 1150.23 - Filing and service.
Code of Federal Regulations, 2014 CFR
2014-07-01
... legal holidays excepted) from 9 a.m. to 5:30 p.m. Standard or Daylight Savings Time, whichever is effective in the city where the office of the judge is located at the time. (c) Service. Service of one copy...
17 CFR 230.459 - Calculation of effective date.
Code of Federal Regulations, 2010 CFR
2010-04-01
... of 24 hours each from 5:30 p.m. eastern standard time or eastern daylight-saving time, whichever is in effect at the principal office of the Commission on the date of filing. [Reg. C, 12 FR 4075, June...
17 CFR 230.459 - Calculation of effective date.
Code of Federal Regulations, 2011 CFR
2011-04-01
... of 24 hours each from 5:30 p.m. eastern standard time or eastern daylight-saving time, whichever is in effect at the principal office of the Commission on the date of filing. [Reg. C, 12 FR 4075, June...
17 CFR 230.459 - Calculation of effective date.
Code of Federal Regulations, 2014 CFR
2014-04-01
... of 24 hours each from 5:30 p.m. eastern standard time or eastern daylight-saving time, whichever is in effect at the principal office of the Commission on the date of filing. [Reg. C, 12 FR 4075, June...
17 CFR 230.459 - Calculation of effective date.
Code of Federal Regulations, 2012 CFR
2012-04-01
... of 24 hours each from 5:30 p.m. eastern standard time or eastern daylight-saving time, whichever is in effect at the principal office of the Commission on the date of filing. [Reg. C, 12 FR 4075, June...
17 CFR 230.459 - Calculation of effective date.
Code of Federal Regulations, 2013 CFR
2013-04-01
... of 24 hours each from 5:30 p.m. eastern standard time or eastern daylight-saving time, whichever is in effect at the principal office of the Commission on the date of filing. [Reg. C, 12 FR 4075, June...
An investigation of streaking on highway traffic signs.
DOT National Transportation Integrated Search
1974-01-01
During a night inspection, dark streaks were observed on the faces of many reflectorized highway signs. Although the streaks were not visible during daylight, they substantially reduced the reflectivity of the signs at night. This study was initiated...
78 FR 32474 - Request for Comments: LSC Appropriations Request for FY 2015
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-30
... and is seeking public comment and testimony on what the amount of its request should be. DATES... p.m., Eastern Daylight Time, on Thursday June 6, 2013. LSC invites public comment on what its FY...
Urban Stream Burial Increases Watershed-Scale Nitrate Export.
Beaulieu, Jake J; Golden, Heather E; Knightes, Christopher D; Mayer, Paul M; Kaushal, Sujay S; Pennino, Michael J; Arango, Clay P; Balz, David A; Elonen, Colleen M; Fritz, Ken M; Hill, Brian H
2015-01-01
Nitrogen (N) uptake in streams is an important ecosystem service that reduces nutrient loading to downstream ecosystems. Here we synthesize studies that investigated the effects of urban stream burial on N-uptake in two metropolitan areas and use simulation modeling to scale our measurements to the broader watershed scale. We report that nitrate travels on average 18 times farther downstream in buried than in open streams before being removed from the water column, indicating that burial substantially reduces N uptake in streams. Simulation modeling suggests that as burial expands throughout a river network, N uptake rates increase in the remaining open reaches which somewhat offsets reduced N uptake in buried reaches. This is particularly true at low levels of stream burial. At higher levels of stream burial, however, open reaches become rare and cumulative N uptake across all open reaches in the watershed rapidly declines. As a result, watershed-scale N export increases slowly at low levels of stream burial, after which increases in export become more pronounced. Stream burial in the lower, more urbanized portions of the watershed had a greater effect on N export than an equivalent amount of stream burial in the upper watershed. We suggest that stream daylighting (i.e., uncovering buried streams) can increase watershed-scale N retention.
Urban Stream Burial Increases Watershed-Scale Nitrate Export
Beaulieu, Jake J.; Golden, Heather E.; Knightes, Christopher D.; Mayer, Paul M.; Kaushal, Sujay S.; Pennino, Michael J.; Arango, Clay P.; Balz, David A.; Elonen, Colleen M.; Fritz, Ken M.; Hill, Brian H.
2015-01-01
Nitrogen (N) uptake in streams is an important ecosystem service that reduces nutrient loading to downstream ecosystems. Here we synthesize studies that investigated the effects of urban stream burial on N-uptake in two metropolitan areas and use simulation modeling to scale our measurements to the broader watershed scale. We report that nitrate travels on average 18 times farther downstream in buried than in open streams before being removed from the water column, indicating that burial substantially reduces N uptake in streams. Simulation modeling suggests that as burial expands throughout a river network, N uptake rates increase in the remaining open reaches which somewhat offsets reduced N uptake in buried reaches. This is particularly true at low levels of stream burial. At higher levels of stream burial, however, open reaches become rare and cumulative N uptake across all open reaches in the watershed rapidly declines. As a result, watershed-scale N export increases slowly at low levels of stream burial, after which increases in export become more pronounced. Stream burial in the lower, more urbanized portions of the watershed had a greater effect on N export than an equivalent amount of stream burial in the upper watershed. We suggest that stream daylighting (i.e., uncovering buried streams) can increase watershed-scale N retention. PMID:26186731
Comprehensive design of omnidirectional high-performance perovskite solar cells
Zhang, Yutao; Xuan, Yimin
2016-01-01
The comprehensive design approach is established with coupled optical-electrical simulation for perovskite-based solar cell, which emerged as one of the most promising competitors to silicon solar cell for its low-cost fabrication and high PCE. The selection of structured surface, effect of geometry parameters, incident angle-dependence and polarization-sensitivity are considered in the simulation. The optical modeling is performed via the finite-difference time-domain method whilst the electrical properties are obtained by solving the coupled nonlinear equations of Poisson, continuity, and drift-diffusion equations. The optical and electrical performances of five different structured surfaces are compared to select a best structured surface for perovskite solar cell. The effects of the geometry parameters on the optical and electrical properties of the perovskite cell are analyzed. The results indicate that the light harvesting is obviously enhanced by the structured surface. The electrical performance can be remarkably improved due to the enhanced light harvesting of the designed best structured surface. The angle-dependence for s- and p-polarizations is investigated. The structured surface exhibits omnidirectional behavior and favorable polarization-insensitive feature within a wide incident angle range. Such a comprehensive design approach can highlight the potential of perovskite cell for power conversion in the full daylight. PMID:27405419
Comprehensive design of omnidirectional high-performance perovskite solar cells.
Zhang, Yutao; Xuan, Yimin
2016-07-13
The comprehensive design approach is established with coupled optical-electrical simulation for perovskite-based solar cell, which emerged as one of the most promising competitors to silicon solar cell for its low-cost fabrication and high PCE. The selection of structured surface, effect of geometry parameters, incident angle-dependence and polarization-sensitivity are considered in the simulation. The optical modeling is performed via the finite-difference time-domain method whilst the electrical properties are obtained by solving the coupled nonlinear equations of Poisson, continuity, and drift-diffusion equations. The optical and electrical performances of five different structured surfaces are compared to select a best structured surface for perovskite solar cell. The effects of the geometry parameters on the optical and electrical properties of the perovskite cell are analyzed. The results indicate that the light harvesting is obviously enhanced by the structured surface. The electrical performance can be remarkably improved due to the enhanced light harvesting of the designed best structured surface. The angle-dependence for s- and p-polarizations is investigated. The structured surface exhibits omnidirectional behavior and favorable polarization-insensitive feature within a wide incident angle range. Such a comprehensive design approach can highlight the potential of perovskite cell for power conversion in the full daylight.
Aspects of detection and tracking of ground targets from an airborne EO/IR sensor
NASA Astrophysics Data System (ADS)
Balaji, Bhashyam; Sithiravel, Rajiv; Daya, Zahir; Kirubarajan, Thiagalingam
2015-05-01
An airborne EO/IR (electro-optical/infrared) camera system comprises of a suite of sensors, such as a narrow and wide field of view (FOV) EO and mid-wave IR sensors. EO/IR camera systems are regularly employed on military and search and rescue aircrafts. The EO/IR system can be used to detect and identify objects rapidly in daylight and at night, often with superior performance in challenging conditions such as fog. There exist several algorithms for detecting potential targets in the bearing elevation grid. The nonlinear filtering problem is one of estimation of the kinematic parameters from bearing and elevation measurements from a moving platform. In this paper, we developed a complete model for the state of a target as detected by an airborne EO/IR system and simulated a typical scenario with single target with 1 or 2 airborne sensors. We have demonstrated the ability to track the target with `high precision' and noted the improvement from using two sensors on a single platform or on separate platforms. The performance of the Extended Kalman filter (EKF) is investigated on simulated data. Image/video data collected from an IR sensor on an airborne platform are processed using an image tracking by detection algorithm.
Refractory Sampling Links Efficiency and Costs of Sensory Encoding to Stimulus Statistics
Song, Zhuoyi
2014-01-01
Sensory neurons integrate information about the world, adapting their sampling to its changes. However, little is understood mechanistically how this primary encoding process, which ultimately limits perception, depends upon stimulus statistics. Here, we analyze this open question systematically by using intracellular recordings from fly (Drosophila melanogaster and Coenosia attenuata) photoreceptors and corresponding stochastic simulations from biophysically realistic photoreceptor models. Recordings show that photoreceptors can sample more information from naturalistic light intensity time series (NS) than from Gaussian white-noise (GWN), shuffled-NS or Gaussian-1/f stimuli; integrating larger responses with higher signal-to-noise ratio and encoding efficiency to large bursty contrast changes. Simulations reveal how a photoreceptor's information capture depends critically upon the stochastic refractoriness of its 30,000 sampling units (microvilli). In daylight, refractoriness sacrifices sensitivity to enhance intensity changes in neural image representations, with more and faster microvilli improving encoding. But for GWN and other stimuli, which lack longer dark contrasts of real-world intensity changes that reduce microvilli refractoriness, these performance gains are submaximal and energetically costly. These results provide mechanistic reasons why information sampling is more efficient for natural/naturalistic stimulation and novel insight into the operation, design, and evolution of signaling and code in sensory neurons. PMID:24849356
NASA Astrophysics Data System (ADS)
Kőrösi, László; Prato, Mirko; Scarpellini, Alice; Kovács, János; Dömötör, Dóra; Kovács, Tamás; Papp, Szilvia
2016-03-01
Hierarchically assembled flower-like rutile TiO2 (FLH-R-TiO2) nanostructures were successfully synthesized from TiCl4 at room temperature without the use of surfactants or templates. An initial sol-gel synthesis at room temperature allowed long-term hydrolysis and condensation of the precursors. The resulting FLH-R-TiO2 possessed relatively high crystallinity (85 wt%) and consisted of rod-shaped subunits assembling into cauliflower-like nanostructures. Hydrothermal evolution of FLH-R-TiO2 at different temperatures (150, 200 and 250 °C) was followed by means of X-ray diffraction, transmission and scanning electron microscopy. These FLH-R-TiO2 nanostructures were tested as photocatalysts under simulated daylight (full-spectrum lighting) in the degradation of methyl orange and in the inactivation of a multiresistant bacterium, Klebsiella pneumoniae. The effects of hydrothermal treatment on the structure, photocatalytic behavior and antibacterial activity of FLH-R-TiO2 are discussed.
A Context-Aware Method for Authentically Simulating Outdoors Shadows for Mobile Augmented Reality.
Barreira, Joao; Bessa, Maximino; Barbosa, Luis; Magalhaes, Luis
2018-03-01
Visual coherence between virtual and real objects is a major issue in creating convincing augmented reality (AR) applications. To achieve this seamless integration, actual light conditions must be determined in real time to ensure that virtual objects are correctly illuminated and cast consistent shadows. In this paper, we propose a novel method to estimate daylight illumination and use this information in outdoor AR applications to render virtual objects with coherent shadows. The illumination parameters are acquired in real time from context-aware live sensor data. The method works under unprepared natural conditions. We also present a novel and rapid implementation of a state-of-the-art skylight model, from which the illumination parameters are derived. The Sun's position is calculated based on the user location and time of day, with the relative rotational differences estimated from a gyroscope, compass and accelerometer. The results illustrated that our method can generate visually credible AR scenes with consistent shadows rendered from recovered illumination.
Prospect of life on cold planets with low atmospheric pressures
NASA Astrophysics Data System (ADS)
Pavlov, A. A.; Vdovina, M.
2009-12-01
Stable liquid water on the surface of a planet has been viewed as the major requirement for a habitable planet. Such approach would exclude planets with low atmospheric pressures and cold mean surface temperatures (like present Mars) as potential candidates for extraterrestrial life search. Here we explore a possibility of the liquid water formation in the extremely shallow (1-3 cm) subsurface layer under low atmospheric pressures (0.1-10 mbar) and low average surface temperatures (~-30 C). During brief periods of simulated daylight warming the shallow subsurface ice sublimates, the water vapor can diffuse through the porous surface layer of soil temporarily producing supersaturated conditions in the soil, which lead to the formation of liquid films. We show that non-extremophile terrestrial microorganisms (Vibrio sp.) can grow and reproduce under such conditions. The necessary conditions for metabolism and reproduction are the sublimation of ground ice through a thin layer of soil and short episodes of warm temperatures at the planetary surface.
Color constancy: phenomenal or projective?
Reeves, Adam J; Amano, Kinjiro; Foster, David H
2008-02-01
Naive observers viewed a sequence of colored Mondrian patterns, simulated on a color monitor. Each pattern was presented twice in succession, first under one daylight illuminant with a correlated color temperature of either 16,000 or 4000 K and then under the other, to test for color constancy. The observers compared the central square of the pattern across illuminants, either rating it for sameness of material appearance or sameness of hue and saturation or judging an objective property-that is, whether its change of color originated from a change in material or only from a change in illumination. Average color constancy indices were high for material appearance ratings and binary judgments of origin and low for hue-saturation ratings. Individuals' performance varied, but judgments of material and of hue and saturation remained demarcated. Observers seem able to separate phenomenal percepts from their ontological projections of mental appearance onto physical phenomena; thus, even when a chromatic change alters perceived hue and saturation, observers can reliably infer the cause, the constancy of the underlying surface spectral reflectance.
Beyond the cockpit: The visual world as a flight instrument
NASA Technical Reports Server (NTRS)
Johnson, W. W.; Kaiser, M. K.; Foyle, D. C.
1992-01-01
The use of cockpit instruments to guide flight control is not always an option (e.g., low level rotorcraft flight). Under such circumstances the pilot must use out-the-window information for control and navigation. Thus it is important to determine the basis of visually guided flight for several reasons: (1) to guide the design and construction of the visual displays used in training simulators; (2) to allow modeling of visibility restrictions brought about by weather, cockpit constraints, or distortions introduced by sensor systems; and (3) to aid in the development of displays that augment the cockpit window scene and are compatible with the pilot's visual extraction of information from the visual scene. The authors are actively pursuing these questions. We have on-going studies using both low-cost, lower fidelity flight simulators, and state-of-the-art helicopter simulation research facilities. Research results will be presented on: (1) the important visual scene information used in altitude and speed control; (2) the utility of monocular, stereo, and hyperstereo cues for the control of flight; (3) perceptual effects due to the differences between normal unaided daylight vision, and that made available by various night vision devices (e.g., light intensifying goggles and infra-red sensor displays); and (4) the utility of advanced contact displays in which instrument information is made part of the visual scene, as on a 'scene linked' head-up display (e.g., displaying altimeter information on a virtual billboard located on the ground).
ERIC Educational Resources Information Center
Shimm, Jon
2001-01-01
Discusses how incorporating energy-efficient features into residence halls can save money and make students' campus experience more enjoyable. Use of heat-recovery systems, low-impact lighting, and natural daylighting are explored as are ideas to consider for future residence hall construction projects or renovations. (GR)
77 FR 59014 - Sunshine Act Meeting; Notice
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-25
... the meetings of the Institutional Advancement Committee and the Audit Committee, which will run... Eastern Daylight Time. ** The meeting of the Institutional Advancement Committee will run concurrently.... Institutional Advancement Committee** 5. Audit Committee Monday, October 1, 2012 1. Promotion & Provision for...
36 CFR § 1150.23 - Filing and service.
Code of Federal Regulations, 2013 CFR
2013-07-01
... (Federal legal holidays excepted) from 9 a.m. to 5:30 p.m. Standard or Daylight Savings Time, whichever is effective in the city where the office of the judge is located at the time. (c) Service. Service of one copy...
ERIC Educational Resources Information Center
Turckes, Steven; Engelbrecht, Kathie
2002-01-01
Discusses incorporating green design into school construction, asserting that schools can improve their impact on the environment and reduce their operating costs while educating people about the value of sustainable design. Addresses energy reduction (including daylighting), site design for low environmental impact, flexible design, indoor air…
Driver electronic device use in 2008
DOT National Transportation Integrated Search
2009-09-01
The 2008 hand-held cell phone use rate translates into 812,000 vehicles being driven by someone using a hand-held cell phone at any given daylight moment.1 It also translates into an estimated 11 percent of the vehicles whose drivers were using some ...
78 FR 46596 - Secretarial Commission on Indian Trust Administration and Reform
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-01
... begin at 8:30 a.m. and end at 1 p.m. Alaska Daylight Time on August 19, 2013. Members of the public who... meals are the responsibility of the participating public. To review all related material on the...
ERIC Educational Resources Information Center
Rittner-Heir, Robbin M.
2002-01-01
Discusses studies showing that color and light have a significant influence on how students learn and retain information (for example, daylight is much more beneficial than fluorescent light). Describes how many architects and designers are now incorporating these findings into their work in schools. (EV)
Development and test of selected model pedestrian safety regulations
DOT National Transportation Integrated Search
1981-04-01
Two model regulations to remove parking--one from suburban streets in daylight hours and one on the last 50 feet of the approach to crosswalks--were designed in previous work to prevent pedestrian dart and dash accidents by removing screening vehicle...
DETAIL TOP VIEW OF AERIAL TRAMWAY DRIVE MECHANISM, LOOKING NORTHEAST. ...
DETAIL TOP VIEW OF AERIAL TRAMWAY DRIVE MECHANISM, LOOKING NORTHEAST. THE FRICTION BRAKING SYSTEM CAN BE SEEN IN SHADOW ABOVE THE LARGE CABLE WHEEL BELOW. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA
Color defective vision and the recognition of aviation color signal light flashes.
DOT National Transportation Integrated Search
1971-06-01
A previous study reported on the efficiency with which various tests of color defective vision can predict performance during daylight conditions on a practical test of ability to discriminate aviation signal red, white, and green. In the current stu...
Lighting the School of the Future.
ERIC Educational Resources Information Center
Clanton, Nancy
1999-01-01
Discusses the Austin Independent School District's (Texas) school redesign efforts to allow more daylight in its schools, increase the students' comfort and productivity, and lower utility costs. Return on investment potential from savings in maintenance, replacement, and productivity of the school are highlighted. (GR)
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-01
...). The Order was effective at 12:01 a.m. eastern daylight time on July 25, 2011. In the Order, the..., Marina), Burj Khalifa, Dubai, United Arab Emirates; DOB 15 Sep 1979; Passport 514763020 (Russia...
Fault Analysis in Solar Photovoltaic Arrays
NASA Astrophysics Data System (ADS)
Zhao, Ye
Fault analysis in solar photovoltaic (PV) arrays is a fundamental task to increase reliability, efficiency and safety in PV systems. Conventional fault protection methods usually add fuses or circuit breakers in series with PV components. But these protection devices are only able to clear faults and isolate faulty circuits if they carry a large fault current. However, this research shows that faults in PV arrays may not be cleared by fuses under some fault scenarios, due to the current-limiting nature and non-linear output characteristics of PV arrays. First, this thesis introduces new simulation and analytic models that are suitable for fault analysis in PV arrays. Based on the simulation environment, this thesis studies a variety of typical faults in PV arrays, such as ground faults, line-line faults, and mismatch faults. The effect of a maximum power point tracker on fault current is discussed and shown to, at times, prevent the fault current protection devices to trip. A small-scale experimental PV benchmark system has been developed in Northeastern University to further validate the simulation conclusions. Additionally, this thesis examines two types of unique faults found in a PV array that have not been studied in the literature. One is a fault that occurs under low irradiance condition. The other is a fault evolution in a PV array during night-to-day transition. Our simulation and experimental results show that overcurrent protection devices are unable to clear the fault under "low irradiance" and "night-to-day transition". However, the overcurrent protection devices may work properly when the same PV fault occurs in daylight. As a result, a fault under "low irradiance" and "night-to-day transition" might be hidden in the PV array and become a potential hazard for system efficiency and reliability.
Cha, Hyun-Suk; Yu, Bin
2013-01-01
PURPOSE Perceived color of ceramics changes by the spectral power distribution of ambient light. This study aimed to quantify the amount of shifts in color and color coordinates of clinically simulated seven all-ceramics due to the switch of three ambient light sources using a human vision simulating spectroradiometer. MATERIALS AND METHODS CIE color coordinates, such as L*, a* and b*,of ceramic specimens were measured under three light sources, which simulate the CIE standard illuminant D65 (daylight), A (incandescent lamp), and F9 (fluorescent lamp). Shifts in color and color coordinate by the switch of lights were determined. Influence of the switched light (D65 to A, or D65 to F9), shade of veneer ceramics (A2 or A3), and brand of ceramics on the shifts was analyzed by a three-way ANOVA. RESULTS Shifts in color and color coordinates were influenced by three factors (P<.05). Color shifts by the switch to A were in the range of 5.9 to 7.7 ΔE*abunits, and those by the switch to F9 were 7.7 to 10.2; all of which were unacceptable (ΔE*ab > 5.5). When switched to A, CIE a* increased (Δa*: 5.6 to 7.6), however, CIE b* increased (Δb*: 4.9 to 7.8) when switched to F9. CONCLUSION Clinically simulated ceramics demonstrated clinically unacceptable color shifts according to the switches in ambient lights based on spectroradiometric readings. Therefore, shade matching and compatibility evaluation should be performed considering ambient lighting conditions and should be done under most relevant lighting condition. PMID:24049567
Advanced lighting guidelines: 1993. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eley, C.; Tolen, T.M.; Benya, J.R.
1993-12-31
The 1993 Advanced Lighting Guidelines document consists of twelve guidelines that provide an overview of specific lighting technologies and design application techniques utilizing energy-efficient lighting practice. Lighting Design Practice assesses energy-efficient lighting strategies, discusses lighting issues, and explains how to obtain quality lighting design and consulting services. Luminaires and Lighting Systems surveys luminaire equipment designed to take advantage of advanced technology lamp products and includes performance tables that allow for accurate estimation of luminaire light output and power input. The additional ten guidelines -- Computer-Aided Lighting Design, Energy-Efficient Fluorescent Ballasts, Full-Size Fluorescent Lamps, Compact Fluorescent Lamps, Tungsten-Halogen Lamps, Metal Halidemore » and HPS Lamps, Daylighting and Lumen Maintenance, Occupant Sensors, Time Scheduling Systems, and Retrofit Control Technologies -- each provide a product technology overview, discuss current products on the lighting equipment market, and provide application techniques. This document is intended for use by electric utility personnel involved in lighting programs, lighting designers, electrical engineers, architects, lighting manufacturers` representatives, and other lighting professionals.« less
Analysis of differential and active charging phenomena on ATS-5 and ATS-6
NASA Technical Reports Server (NTRS)
Olsen, R. C.; Whipple, E. C., Jr.
1980-01-01
Spacecraft charging on the differential charging and artificial particle emission experiments on ATS 5 and ATS 6 were studied. Differential charging of spacecraft surfaces generated large electrostatic barriers to spacecraft generated electrons, from photoemission, secondary emission, and thermal emitters. The electron emitter could partially or totally discharge the satellite, but the mainframe recharged negatively in a few 10's of seconds. The time dependence of the charging behavior was explained by the relatively large capacitance for differential charging in comparison to the small spacecraft to space capacitance. A daylight charging event on ATS 6 was shown to have a charging behavior suggesting the dominance of differential charging on the absolute potential of the mainframe. Ion engine operations and plasma emission experiments on ATS 6 were shown to be an effective means of controlling the spacecraft potential in eclipse and sunlight. Elimination of barrier effects around the detectors and improving the quality of the particle data are discussed.
Long-range depth profiling of camouflaged targets using single-photon detection
NASA Astrophysics Data System (ADS)
Tobin, Rachael; Halimi, Abderrahim; McCarthy, Aongus; Ren, Ximing; McEwan, Kenneth J.; McLaughlin, Stephen; Buller, Gerald S.
2018-03-01
We investigate the reconstruction of depth and intensity profiles from data acquired using a custom-designed time-of-flight scanning transceiver based on the time-correlated single-photon counting technique. The system had an operational wavelength of 1550 nm and used a Peltier-cooled InGaAs/InP single-photon avalanche diode detector. Measurements were made of human figures, in plain view and obscured by camouflage netting, from a stand-off distance of 230 m in daylight using only submilliwatt average optical powers. These measurements were analyzed using a pixelwise cross correlation approach and compared to analysis using a bespoke algorithm designed for the restoration of multilayered three-dimensional light detection and ranging images. This algorithm is based on the optimization of a convex cost function composed of a data fidelity term and regularization terms, and the results obtained show that it achieves significant improvements in image quality for multidepth scenarios and for reduced acquisition times.
Daytime Utilization of a University Observatory for Laboratory Instruction
NASA Astrophysics Data System (ADS)
Mattox, J. R.
2006-08-01
Scheduling convenience provides a strong incentive to fully explore effective utilization of educational observatories during daylight hours. I present two compelling daytime student activities that I developed at the Observatory at Fayetteville State University. My Introductory Astronomy Laboratory classes pursue these as separate investigations. My Physical Science classes complete both in a single lab period of 110 minutes duration. Both of these activities are also appropriate for High School student investigators, and could be used as demonstrations for younger students. Daylight Observation of Venus. With a clear sky, and when its elongation exceeds ~20˚, Venus is readily apparent in the daytime sky once a telescope is pointed at it. This is accomplished either with a digital pointing system, or with setting circles on a polar-aligned mount using the Sun to initialize the RA circle. Using the telescope pointing as a reference, it is also possible under optimal circumstances for students to see Venus in the daytime sky with naked eyes. Students are asked to write about the circumstances that made it possible to see Venus. Educational utilization of daytime observations of the Moon, Jupiter, Saturn, and the brightest stars are also discussed. Using a CCD Camera to Determine the Temperature of a Sunspot. After my students view the Sun with Eclipse Glasses and in projection using a 3-inch refractor, they analyze a CCD image of a sunspot (which they obtain if possible) to determine the ratio of its surface intensity relative to the normal solar surface. They then use the Stefan-Boltzmann law (usually with some coaching) to determine the sunspot temperature given the nominal surface temperature of the Sun. Appropriate safety precautions are presented given the hazards of magnified sunlight. Mitigation of dome seeing during daylight hours is discussed.
Driver hand-held cellular phone use: a four-year analysis.
Eby, David W; Vivoda, Jonathon M; St Louis, Renée M
2006-01-01
The use of hand-held cellular (mobile) phones while driving has stirred more debate, passion, and research than perhaps any other traffic safety issue in the past several years. There is ample research showing that the use of either hand-held or hands-free cellular phones can lead to unsafe driving patterns. Whether or not these performance deficits increase the risk of crash is difficult to establish, but recent studies are beginning to suggest that cellular phone use elevates crash risk. The purpose of this study was to assess changes in the rate of hand-held cellular phone use by motor-vehicle drivers on a statewide level in Michigan. This study presents the results of 13 statewide surveys of cellular phone use over a 4-year period. Hand-held cellular phone use data were collected through direct observation while vehicles were stopped at intersections and freeway exit ramps. Data were weighted to be representative of all drivers traveling during daylight hours in Michigan. The study found that driver hand-held cellular phone use has more than doubled between 2001 and 2005, from 2.7% to 5.8%. This change represents an average increase of 0.78 percentage points per year. The 5.8% use rate observed in 2005 means that at any given daylight hour, around 36,550 drivers were conversing on cellular phones while driving on Michigan roadways. The trend line fitted to these data predicts that by the year 2010, driver hand-held cellular phone use will be around 8.6%, or 55,000 drivers at any given daylight hour. These results make it clear that cellular phone use while driving will continue to be an important traffic safety issue, and highlight the importance of continued attempts to generate new ways of alleviating this potential hazard.
Aldasouqi, Saleh A; Reed, Amy J
2014-11-01
The objective was to raise awareness about the importance of ensuring that insulin pumps internal clocks are set up correctly at all times. This is a very important safety issue because all commercially available insulin pumps are not GPS-enabled (though this is controversial), nor equipped with automatically adjusting internal clocks. Special attention is paid to how basal and bolus dose errors can be introduced by daylight savings time changes, travel across time zones, and am-pm clock errors. Correct setting of insulin pump internal clock is crucial for appropriate insulin delivery. A comprehensive literature review is provided, as are illustrative cases. Incorrect setting can potentially result in incorrect insulin delivery, with potential harmful consequences, if too much or too little insulin is delivered. Daylight saving time changes may not significantly affect basal insulin delivery, given the triviality of the time difference. However, bolus insulin doses can be dramatically affected. Such problems may occur when pump wearers have large variations in their insulin to carb ratio, especially if they forget to change their pump clock in the spring. More worrisome than daylight saving time change is the am-pm clock setting. If this setting is set up incorrectly, both basal rates and bolus doses will be affected. Appropriate insulin delivery through insulin pumps requires correct correlation between dose settings and internal clock time settings. Because insulin pumps are not GPS-enabled or automatically time-adjusting, extra caution should be practiced by patients to ensure correct time settings at all times. Clinicians and diabetes educators should verify the date/time of insulin pumps during patients' visits, and should remind their patients to always verify these settings. © 2014 Diabetes Technology Society.
Impact of daylight saving time on road traffic collision risk: a systematic review.
Carey, Rachel N; Sarma, Kiran M
2017-07-02
Bills have been put forward in the UK and Republic of Ireland proposing a move to Central European Time (CET). Proponents argue that such a change will have benefits for road safety, with daylight being shifted from the morning, when collision risk is lower, to the evening, when risk is higher. Studies examining the impact of daylight saving time (DST) on road traffic collision risk can help inform the debate on the potential road safety benefits of a move to CET. The objective of this systematic review was to examine the impact of DST on collision risk. Major electronic databases were searched, with no restrictions as to date of publication (the last search was performed in January 2017). Access to unpublished reports was requested through an international expert group. Studies that provided a quantitative analysis of the effect of DST on road safety-related outcomes were included. The primary outcomes of interest were road traffic collisions, injuries and fatalities. Twenty-four studies met the inclusion criteria. Seventeen examined the short-term impact of transitions around DST and 12 examined long-term effects. Findings from the short-term studies were inconsistent. The long-term findings suggested a positive effect of DST. However, this cannot be attributed solely to DST, as a range of road collision risk factors vary over time. The evidence from this review cannot support or refute the assertion that a permanent shift in light from morning to evening will have a road safety benefit. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Li, Qiaoxia; Huo, Qingdi; Wang, Juan; Zhao, Jing; Sun, Kun; He, Chaoying
2016-07-07
Some plants develop a breeding system that produces both chasmogamous (CH) and cleistogamous (CL) flowers. However, the underlying molecular mechanism remains elusive. In the present study, we observed that Viola philippica develops CH flowers with short daylight, whereas an extended photoperiod induces the formation of intermediate CL and CL flowers. In response to long daylight, the respective number and size of petals and stamens was lower and smaller than those of normally developed CH flowers, and a minimum of 14-h light induced complete CL flowers that had no petals but developed two stamens of reduced fertility. The floral ABC model indicates that B-class MADS-box genes largely influence the development of the affected two-whorl floral organs; therefore, we focused on characterizing these genes in V. philippica to understand this particular developmental transition. Three such genes were isolated and respectively designated as VpTM6-1, VpTM6-2, and VpPI. These were differentially expressed during floral development (particularly in petals and stamens) and the highest level of expression was observed in CH flowers; significantly low levels were detected in intermediate CL flowers, and the lowest level in CL flowers. The observed variations in the levels of expression after floral induction and organogenesis apparently occurred in response to variations in photoperiod. Therefore, inhibition of the development of petals and stamens might be due to the downregulation of B-class MADS-box gene expression by long daylight, thereby inducing the generation of CL flowers. Our work contributes to the understanding of the adaptive evolutionary formation of dimorphic flowers in plants.
Adverse Effects of Daylight Saving Time on Adolescents' Sleep and Vigilance
Medina, Diana; Ebben, Matthew; Milrad, Sara; Atkinson, Brianna; Krieger, Ana C.
2015-01-01
Study Objectives: Daylight saving time (DST) has been established with the intent to reduce energy expenditure, however unintentional effects on sleep and vigilance have not been consistently measured. The objective of this study was to test the hypothesis that DST adversely affects high school students' sleep and vigilance on the school days following its implementation. Methods: A natural experiment design was used to assess baseline and post-DST differences in objective and subjective measures of sleep and vigilance by actigraphy, sleep diary, sleepiness scale, and psychomotor vigilance testing (PVT). Students were tested during school days immediately preceding and following DST. Results: A total of 40 high school students were enrolled in this study; 35 completed the protocol. Sleep duration declined by an average of 32 minutes on the weeknights post-DST, reflecting a cumulative sleep loss of 2 h 42 min as compared to the baseline week (p = 0.001). This finding was confirmed by sleep diary analyses, reflecting an average sleep loss of 27 min/night (p = 0.004) post-DST. Vigilance significantly deteriorated, with a decline in PVT performance post-DST, resulting in longer reaction times (p < 0.001) and increased lapses (p < 0.001). Increased daytime sleepiness was also demonstrated (p < 0.001). Conclusions: The early March DST onset adversely affected sleep and vigilance in high school students resulting in increased daytime sleepiness. Larger scale evaluations of sleep impairments related to DST are needed to further quantify this problem in the population. If confirmed, measures to attenuate sleep loss post-DST should be implemented. Citation: Medina D, Ebben M, Milrad S, Atkinson B, Krieger AC. Adverse effects of daylight saving time on adolescents' sleep and vigilance. J Clin Sleep Med 2015;11(8):879–884. PMID:25979095
Quantifying riverine surface currents from time sequences of thermal infrared imagery
Puleo, J.A.; McKenna, T.E.; Holland, K.T.; Calantoni, J.
2012-01-01
River surface currents are quantified from thermal and visible band imagery using two methods. One method utilizes time stacks of pixel intensity to estimate the streamwise velocity at multiple locations. The other method uses particle image velocimetry to solve for optimal two-dimensional pixel displacements between successive frames. Field validation was carried out on the Wolf River, a small coastal plain river near Landon, Mississippi, United States, on 26-27 May 2010 by collecting imagery in association with in situ velocities sampled using electromagnetic current meters deployed 0.1 m below the river surface. Comparisons are made between mean in situ velocities and image-derived velocities from 23 thermal and 6 visible-band image sequences (5 min length) during daylight and darkness conditions. The thermal signal was a small apparent temperature contrast induced by turbulent mixing of a thin layer of cooler water near the river surface with underlying warmer water. The visible-band signal was foam on the water surface. For thermal imagery, streamwise velocities derived from the pixel time stack and particle image velocimetry technique were generally highly correlated to mean streamwise current meter velocities during darkness (r 2 typically greater than 0.9) and early morning daylight (r 2 typically greater than 0.83). Streamwise velocities from the pixel time stack technique had high correlation for visible-band imagery during early morning daylight hours with respect to mean current meter velocities (r 2 > 0.86). Streamwise velocities for the particle image velocimetry technique for visible-band imagery had weaker correlations with only three out of six correlations performed having an r 2 exceeding 0.6. Copyright 2012 by the American Geophysical Union.
Pitfalls of Insulin Pump Clocks
Reed, Amy J.
2014-01-01
The objective was to raise awareness about the importance of ensuring that insulin pumps internal clocks are set up correctly at all times. This is a very important safety issue because all commercially available insulin pumps are not GPS-enabled (though this is controversial), nor equipped with automatically adjusting internal clocks. Special attention is paid to how basal and bolus dose errors can be introduced by daylight savings time changes, travel across time zones, and am-pm clock errors. Correct setting of insulin pump internal clock is crucial for appropriate insulin delivery. A comprehensive literature review is provided, as are illustrative cases. Incorrect setting can potentially result in incorrect insulin delivery, with potential harmful consequences, if too much or too little insulin is delivered. Daylight saving time changes may not significantly affect basal insulin delivery, given the triviality of the time difference. However, bolus insulin doses can be dramatically affected. Such problems may occur when pump wearers have large variations in their insulin to carb ratio, especially if they forget to change their pump clock in the spring. More worrisome than daylight saving time change is the am-pm clock setting. If this setting is set up incorrectly, both basal rates and bolus doses will be affected. Appropriate insulin delivery through insulin pumps requires correct correlation between dose settings and internal clock time settings. Because insulin pumps are not GPS-enabled or automatically time-adjusting, extra caution should be practiced by patients to ensure correct time settings at all times. Clinicians and diabetes educators should verify the date/time of insulin pumps during patients’ visits, and should remind their patients to always verify these settings. PMID:25355713
Gas discharge headlights and visibility of coloured road signs.
Venkatachalam, Kannan; Smith, George
2000-01-01
BACKGROUND: Automotive headlamps mostly use the tungsten halogen bulb but several years ago a new type of headlamp, the gas discharge bulb, was introduced. Because of the different spectral output of this type of lamp, there has been a suggestion that it may affect the colour recognition and sign conspicuity under night-time conditions. In this study, the visibility of the road signs is used to examine the effect of the gas discharge lamp's spectrum compared with that of the conventional halogen headlamp. METHODS: The spectral output of the lamps and the spectral reflectance of common-coloured road signs were measured using a Spectra-Pritchard spectroradiometer. Using luminous reflectance data, chromaticity co-ordinates and the colorimetric shift of the road signs, when illuminated by gas discharge lamps, were plotted using CIE x,y co-ordinate system. Colour rendering indices of the lamp were calculated using Munsell samples and road signs as proscribed by the CIE Publication. In addition, the visibility index of the road signs was calculated using Adrian's 'Visibility of Target' model. RESULTS: The gas discharge headlamp has more energy in the blue region and less energy in the red region of the spectrum than the halogen headlamp. The general colour rendering index of the gas discharge lamp is higher than that of the halogen lamp. When compared with daylight, all coloured road signs used in this study have less colorimetric shift when illuminated by the gas discharge headlamp than by the halogen headlamp. CONCLUSION: The result indicates that the gas discharge lamp, while having a very different spectrum from daylight or tungsten halogen lamps, should not have a deleterious effect on sign detection or recognition, when compared to daylight or tungsten halogen lamps.
Li, Rong; Liu, Ying; Pedersen, Hanne Skovsgaard; Callesen, Henrik
2015-06-01
Light exposure is a common stress factor during in vitro handling of oocytes and embryos that originates from both microscope and ambient light. In the current study, the effect of two types of ambient light (daylight and laboratory light) on porcine parthenogenetically activated (PA) embryos was tested in two experiments: (1) ambient light on medium subsequently used for embryo in vitro development; and (2) ambient light exposure on activated oocytes before in vitro development. The results from Experiment 1 showed that exposure of culture medium to both types of ambient light decreased the percentage of blastocysts that showed good morphology, only after 24 h exposure. The results from Experiment 2 revealed a reduction in both blastocyst formation and quality when activated oocytes were exposed to both types of ambient light. This effect was seen after only 1 h exposure and increased with time. In conclusion, exposure to ambient light can be harmful to embryo development, both when medium is exposed for a long period of time and, to a greater extent, when the embryo itself is exposed for >1 h. In practice, it is therefore recommended to protect both culture medium and porcine embryos against ambient light during in vitro handling in the laboratory.
Herrera, Christopher P
2012-01-01
Ramadan is a period in which Muslims fast during daylight hours and is associated with disturbances in sleep-wake behaviour and adverse effects on physical and mental health in normal volunteers. Studies using athletes are rare and remain equivocal as to whether Ramadan influences sleep-wake patterns. Notably, the standardized assessment of subjective sleep quality and daytime sleepiness in athletes has not been established. This study employed the Arabic version of the Pittsburgh Sleep Quality Index, Insomnia Severity Index, and Epworth Sleepiness Scale in nine football players aged 20-35 years (mean ± s: 26 ± 4) one week before and during the last week of Ramadan. Compliance rates with self-administration were high (71%) and the results demonstrated a robust decline in total sleep time (before Ramadan: 6.6 ± 2 h; at the end of Ramadan: 5.3 ± 1 h; P < 0.05, effect size 0.81). Compared with previous research, the study questionnaires offer improved methodology, including less time constraints plus standardization in scoring. Thus, this study demonstrates a framework for greater reproducibility and reliability in the assessment of subjective sleep-wake patterns in athletes before and during Ramadan.
Green Infrastructure Benefits for Communities Managing Nitrate in their Drinking Water Sources
Nitrate in water moving through the “biologically active soil zone” of riparian zones, wetlands and streams may undergo denitrification. Therefore GI techniques such as conservation and restoration of riparian zones, wetlands and streams (daylighting) have the potential to remov...
ERIC Educational Resources Information Center
Benya, James R.
This publication highlights some of the benefits of proper daylighting design in educational facilities, discusses energy efficient electric lighting choices schools can make that are long lasting and require little maintenance, and offers six steps for designing lighting systems that use half the energy of earlier conventional designs. Several…
ERIC Educational Resources Information Center
Reicher, Dan
2000-01-01
Discusses school design considerations for energy-efficient schools that provide learning environments that lead to improved student performance. Design myths are addressed as are use of daylighting and designing schools that can teach students and adults about the importance of conserving energy and money. Two online resources are included. (GR)
Color defective vision and day and night recognition of aviation color signal light flashes.
DOT National Transportation Integrated Search
1971-07-01
A previous study reported on the efficiency with which various tests of color defective vision can predict performance during daylight conditions on a practical test of ability to discriminate aviation signal red, white, and green. In the current stu...
ERIC Educational Resources Information Center
Graham, Donald
2009-01-01
The lighting of learning environments is an important focus in designing new schools and renovating older schools. Studies long have shown that appropriate lighting levels and daylighting improve learning; now, climbing energy budgets have spurred school administrators to seek more efficient use of lighting. Electricity rates are expected to rise…
Power, Politics and Purchasing.
ERIC Educational Resources Information Center
Moore, Deborah P.
2000-01-01
Explores the overlapping of energy efficiency, budget-cutting, and facility needs in K-12 schools. Utilities expenditures in schools are discussed for electricity and natural gas as are energy-saving alternatives such as daylighting, solar energy, wind production of power, and geothermal energy. Sources for further information conclude the…
Nighttime enforcement of seat belt laws: an evaluation of three community programs : traffic tech.
DOT National Transportation Integrated Search
2010-04-01
Enforcement of seat belt laws has been conducted largely : during daylight hours. Daytime enforcement programs : have worked well to improve observed belt use rates during : the day, but have been shown less often to affect nighttime : use. Fatality ...
75 FR 17166 - NASA Advisory Council; Aeronautics Committee; Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-05
... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (10-038)] NASA Advisory Council; Aeronautics... Aeronautics and Space Administration announces a meeting of the Aeronautics Committee of the NASA Advisory... a.m. to 1 p.m.; Eastern Daylight Time. ADDRESSES: NASA Langley Research Center, Building 1219, Room...
76 FR 14379 - Marine Fisheries Advisory Committee
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-16
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XA265 Marine... Atmospheric Administration (NOAA), Commerce. ACTION: Notice of open public meeting. SUMMARY: This notice sets...: The meeting is scheduled for March 30, 2011, 2-3:30 p.m., Eastern Daylight Time. ADDRESSES: Conference...
Distributions of native intertidal eelgrass (Zostera marina L.) and non-vegetated substrates in three coastal estuaries of the Pacific Northwest (PNW) were determined using color infrared (CIR) aerial orthophotography during daylight low tides. Comparison of the digital classif...
DOE Office of Scientific and Technical Information (OSTI.GOV)
none,
This LEED Platinum home was built on the site of a 60-year-old bungalow that was demolished. It boasts views of Candlewood Lake, a great deal of daylight, and projected annual energy savings of almost $3,000. This home was awarded a 2013 Housing Innovation Award in the custom builder category.
Safety recommendation : right wing separation
DOT National Transportation Integrated Search
1999-05-28
On April 19, 1999, at about 12:46 p.m. eastern daylight time, a Beech T-34A, N140SW, operated by Sky Warriors, Inc., collided with the ground near Rydall, Georgia, following an inflight separation of the right wing. Both the air transport pilot and t...
Leintz, Rachel; Bond, John W
2013-05-01
Comparisons are made between the visualization of fingerprint corrosion ridge detail on fired brass cartridge casings, where fingerprint sweat was deposited prefiring, using both ultraviolet (UV) and visible (natural daylight) light sources. A reflected ultraviolet imaging system (RUVIS), normally used for visualizing latent fingerprint sweat deposits, is compared with optical interference and digital color mapping of visible light, the latter using apparatus constructed to easily enable selection of the optimum viewing angle. Results show that reflected UV, with a monochromatic UV source of 254 nm, was unable to visualize fingerprint ridge detail on any of 12 casings analyzed, whereas optical interference and digital color mapping using natural daylight yielded ridge detail on three casings. Reasons for the lack of success with RUVIS are discussed in terms of the variation in thickness of the thin film of metal oxide corrosion and absorption wavelengths for the corrosion products of brass. © 2013 American Academy of Forensic Sciences.
Progress Towards Highly Efficient Windows for Zero—Energy Buildings
NASA Astrophysics Data System (ADS)
Selkowitz, Stephen
2008-09-01
Energy efficient windows could save 4 quads/year, with an additional 1 quad/year gain from daylighting in commercial buildings. This corresponds to 13% of energy used by US buildings and 5% of all energy used by the US. The technical potential is thus very large and the economic potential is slowly becoming a reality. This paper describes the progress in energy efficient windows that employ low-emissivity glazing, electrochromic switchable coatings and other novel materials. Dynamic systems are being developed that use sensors and controls to modulate daylighting and shading contributions in response to occupancy, comfort and energy needs. Improving the energy performance of windows involves physics in a variety of application: optics, heat transfer, materials science and applied engineering. Technical solutions must also be compatible with national policy, codes and standards, economics, business practice and investment, real and perceived risks, comfort, health, safety, productivity, amenities, and occupant preference and values. The challenge is to optimize energy performance by understanding and reinforcing the synergetic coupling between these many issues.
Daylight-mediated photodynamic therapy in Spain: advantages and disadvantages.
Pérez-Pérez, L; García-Gavín, J; Gilaberte, Y
2014-09-01
Photodynamic therapy (PDT) is an option for the treatment of actinic keratosis, Bowen disease, and certain types of basal cell carcinoma. It is also used to treat various other types of skin condition, including inflammatory and infectious disorders. The main disadvantages of PDT are the time it takes to administer (both for the patient and for health professionals) and the pain associated with treatment. Daylight-mediated PDT has recently been reported to be an alternative to the conventional approach. Several studies have shown it to be similar in efficacy to and better tolerated than classic PDT for the treatment of mild to moderate actinic keratosis. Nevertheless, most of these studies are from northern Europe, and no data have been reported from southern Europe. The present article reviews the main studies published to date, presents the treatment protocol, and summarizes our experience with a group of treated patients. Copyright © 2013 Elsevier España, S.L.U. y AEDV. All rights reserved.
The twilight envelope: a user-centered approach to describing roadway illumination at night.
Andre, J; Owens, D A
2001-01-01
Visual recognition functions, such as acuity and contrast sensitivity, deteriorate rapidly over the declining luminances found during civil twilight. Thus civil twilight, a critical part of the transition between daylight and darkness, represents lighting conditions that may be useful to describe artificial illumination. Automotive headlamps project a three-dimensional beam that ranges from illumination levels comparable to daylight at the vehicle to the dark limit of civil twilight (3.3 1x) at some distance ahead. This twilight envelope is characterized as a distance beyond which foveal visual functions are severely impaired, and thus it provides a general, functional description of the useful extent of the headlamp beam. This user-centered approach to describing illumination is useful for characterizing visibility when driving at night or in other artificially lit environments. This paper discusses the twilight envelope approach and its application to intervehicle variations in headlamp systems. Actual or potential applications of this research include user-centered description of artificial illumination and driver/pedestrian safety education.
Morning ambush attacks by black-footed ferrets on emerging prairie dogs
Eads, D.A.; Biggins, D.E.; Jachowski, D.S.; Livieri, T.M.; Millspaugh, J.J.; Forsberg, M.
2010-01-01
Black-footed ferrets (Mustela nigripes) often hunt at night, attacking normally diurnal prairie dogs (Cynomys spp.) in underground burrow systems. While monitoring black-footed ferrets in South Dakota during morning daylight hours, we observed an adult female ferret ambush a black-tailed prairie dog (C. ludovicianus) emerging from a burrow. On a neighboring colony, we observed a second adult female ferret engaging in similar ambush behaviors on 12 occasions, although prey was not visible. We retrospectively assessed radio-telemetry data on white-tailed prairie dogs (C. leucurus) and a male and a female ferret to evaluate ferret activity in relation to timing of prairie dog emergence. Activity of radio-collared ferrets was high during the hourly period when prairie dogs first emerged and the following 2 hr, relative to later daylight hours. Such behavior is consistent with behaviors observed in South Dakota. Nighttime movements by ferrets might involve hunting but also reconnaissance of prey preparatory to morning ambush attacks.
2003-07-07
KENNEDY SPACE CENTER, FLA. - From a burst of fire and smoke, the Delta II launch vehicle races into the sky carrying the second Mars Exploration Rover, Opportunity. The bright glare briefly illuminated Florida Space Coast beaches. Opportunity’s dash to Mars began with liftoff at 11:18:15 p.m. Eastern Daylight Time from Cape Canaveral Air Force Station, Fla. The spacecraft separated successfully from the Delta's third stage 83 minutes later, after it had been boosted out of Earth orbit and onto a course toward Mars.
Dillard Drive Middle & Elementary School, Raleigh, North Carolina.
ERIC Educational Resources Information Center
Design Cost Data, 2001
2001-01-01
Presents design features of the Dillard Drive Middle & Elementary School (North Carolina) that incorporates daylighting in the majority of the classrooms, the gymnasium, dining room, and media center. The design also uses advanced lighting controls, fiber optic networking, automatic environmental controls, and an energy management system that…
Code of Federal Regulations, 2011 CFR
2011-10-01
... whenever darkness or weather conditions will preclude completion of the post-test survey effort described in § 216.255. (5) If post-detonation surveys determine that a serious injury or lethal take of a... adequate daylight for pre- and post-detonation monitoring, mission launches may not take place earlier than...
78 FR 70046 - Payment System Risk Policy; Daylight Overdraft Posting Rules
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-22
... INFORMATION CONTACT: Jeffrey D. Walker, Assistant Director (202-721-4559) or Michelle D. Olivier, Financial... Telecommunications Device for the Deaf (TDD) only, please call 202-263-4869. SUPPLEMENTARY INFORMATION: Background... debits and credits to institutions' Federal Reserve accounts for different payment types.\\1\\ The...
1946-09-01
camera is supported on four rubber grummets to a metal base which is normally attached in tho aircraft by bolts. The pistol grip remote control...daylight loading (h) Supply • 24 volts 1.7 35 nun Cino Gun Pantra ( Tyre number unknown) ’ ." The oamora dsscribod below is a clockwork
Schweinfurt Raids and the Pause in Daylight Strategic Bombing
2008-06-13
fundamentally flawed doctrine based upon faulty assumptions and the end result was the heavy loss of aircrew and aircraft. The Schweinfurt missions...maneuverable German fighters due to the Lightning’s turbochargers performing badly at higher altitudes in the high humidity and colder temperatures. The P-38
75 FR 41239 - Sunshine Act; Notice of Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-15
... LEGAL SERVICES CORPORATION Sunshine Act; Notice of Meeting TIME AND DATE: The Legal Services Corporation Board of Directors' Search Committee for LSC President (``Search Committee'' or ``Committee'') will meet on July 20, 2010. The meeting will begin at 4 p.m. (Central Daylight Savings Time) and...
Evaluating autofluorescence in live and dead tarnished plant bug (Lygus lineolaris)
USDA-ARS?s Scientific Manuscript database
Insects exhibit a wide variety of colors, often beautiful, when viewed in daylight conditions. When examined with ultraviolet illumination and fluorescence microscope filters, an additional spectrum of color is visible. Furthermore, some of the fluorescence of insects is visible only in live insects...
30 CFR 254.44 - Calculating response equipment effective daily recovery capacities.
Code of Federal Regulations, 2014 CFR
2014-07-01
..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL-SPILL RESPONSE REQUIREMENTS FOR FACILITIES LOCATED SEAWARD OF THE... operations due to available daylight, sea state, temperature, viscosity, and emulsification of the oil being... specific oil recovery devices, you must submit evidence to substantiate that efficiency factor. Adequate...
30 CFR 254.44 - Calculating response equipment effective daily recovery capacities.
Code of Federal Regulations, 2012 CFR
2012-07-01
..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL-SPILL RESPONSE REQUIREMENTS FOR FACILITIES LOCATED SEAWARD OF THE... operations due to available daylight, sea state, temperature, viscosity, and emulsification of the oil being... specific oil recovery devices, you must submit evidence to substantiate that efficiency factor. Adequate...
NASA Astrophysics Data System (ADS)
Manley, M.; Collins, P.; Gray, L.; O'Gorman, S.; McCavana, J.
2018-02-01
Daylight photodynamic therapy (dl-PDT) is as effective as conventional PDT (c-PDT) for treating actinic keratoses but has the advantage of reducing patient discomfort significantly. Topical dl-PDT and white light-PDT (wl-PDT) differ from c-PDT by way of light sources and methodology. We measured the variables associated with light dose delivery to skin surface and influence of geometry using a radiometer, a spectral radiometer and an illuminance meter. The associated errors of the measurement methods were assessed. The spectral and spatial distribution of the radiant energy from the LED white light source was evaluated in order to define the maximum treatment area, setup and treatment protocol for wl-PDT. We compared the data with two red LED light sources we use for c-PDT. The calculated effective light dose is the product of the normalised absorption spectrum of the photosensitizer, protoporphyrin IX (PpIX), the irradiance spectrum and the treatment time. The effective light dose from daylight ranged from 3 ± 0.4 to 44 ± 6 J cm-2due to varying weather conditions. The effective light dose for wl-PDT was reproducible for treatments but it varied across the treatment area between 4 ± 0.1 J cm-2 at the edge and 9 ± 0.1 J cm-2 centrally. The effective light dose for the red waveband (615-645 nm) was 0.42 ± 0.05 J cm-2 on a clear day, 0.05 ± 0.01 J cm-2 on an overcast day and 0.9 ± 0.01 J cm-2 using the white light. This compares with 0.95 ± 0.01 and 0.84 ± 0.01 J cm-2 for c-PDT devices. Estimated errors associated with indirect determination of daylight effective light dose were very significant, particularly for effective light doses less than 5 J cm-2 (up to 83% for irradiance calculations). The primary source of error is in establishment of the relationship between irradiance or illuminance and effective dose. Use of the O’Mahoney model is recommended using a calibrated logging illuminance meter with the detector in the plane of the treatment area.
[The Effect of Observation Geometry on Polarized Skylight Spectrum].
Zhang, Ren-bin; Wang, Ling-mei; Gao, Jun; Wang, Chi
2015-03-01
Study on polarized skylight spectral characters while observation geometry changing in different solar zenith angles (SZA), viewing zenith angles (VZA) or relative azimuth angles (RAA). Simulation calculation of cloudless daylight polarimetric spectrum is realized based on the solver, vector discrete ordinate method, of radiative transfer equation. In the Sun's principal and perpendicular plane, the spectral irradiance data, varying at wavelengths in the range between 0.4 and 3 μm, are calculated to extend the atmospheric polarization spectral information under the conditions: the MODTRAN solar reference spectrur is the only illuminant source; the main influencing factors of polarized radiative transfer include underlying surface albedo, aerosol layers and components, and the absorption of trace gases. Simulation analysis results: (1) While the relative azimuth angle is zero, the magnitude of spectrum U/I is lower than 10(-7) and V/I is negligible, the degree of polarization and the spectrum Q/I are shaped like the letter V or mirror-writing U. (2) In twilight, when the Sun is not in FOV of the detector, the polarization of the daytime sky has two maximum near 0.51 and 2.75 μm, and a minimum near 1.5 μm. For arbitrary observation geometry, the spectral signal of V/I may be ignored. According to observation geometry, choosing different spectral bands or polarized signal will be propitious to targets detection.
Automated tracking for advanced satellite laser ranging systems
NASA Astrophysics Data System (ADS)
McGarry, Jan F.; Degnan, John J.; Titterton, Paul J., Sr.; Sweeney, Harold E.; Conklin, Brion P.; Dunn, Peter J.
1996-06-01
NASA's Satellite Laser Ranging Network was originally developed during the 1970's to track satellites carrying corner cube reflectors. Today eight NASA systems, achieving millimeter ranging precision, are part of a global network of more than 40 stations that track 17 international satellites. To meet the tracking demands of a steadily growing satellite constellation within existing resources, NASA is embarking on a major automation program. While manpower on the current systems will be reduced to a single operator, the fully automated SLR2000 system is being designed to operate for months without human intervention. Because SLR2000 must be eyesafe and operate in daylight, tracking is often performed in a low probability of detection and high noise environment. The goal is to automatically select the satellite, setup the tracking and ranging hardware, verify acquisition, and close the tracking loop to optimize data yield. TO accomplish the autotracking tasks, we are investigating (1) improved satellite force models, (2) more frequent updates of orbital ephemerides, (3) lunar laser ranging data processing techniques to distinguish satellite returns from noise, and (4) angular detection and search techniques to acquire the satellite. A Monte Carlo simulator has been developed to allow optimization of the autotracking algorithms by modeling the relevant system errors and then checking performance against system truth. A combination of simulator and preliminary field results will be presented.
76 FR 63660 - Sunshine Act Meetings; Notice
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-13
... Daylight Time. ** The meeting of the Institutional Advancement Committee will run concurrently with the...** 2:15 p.m. 3. Institutional Advancement Committee** 3:00 p.m. 4. Audit Committee** 3:30 p.m. Tuesday... benefits plan document, to consider and act on the report of the Institutional Advancement Committee...
49 CFR 1.21 - Reservations of Authority to the Secretary of Transportation.
Code of Federal Regulations, 2014 CFR
2014-10-01
... and advanced (daylight) time (15 U.S.C. 260 et seq.). (2) Legislation, rulemakings, and reports. (i... President or Congress of any report or any proposed transportation policy or investment standards or... to career Civil Service positions. (v) Approval of employment of experts or consultants. (vi...
ERIC Educational Resources Information Center
Kennedy, Mike
2006-01-01
In recent years, scores of educators and designers have been won over to the view that natural light--provided by the sun instead of bulbs or tubes--is desirable and beneficial for education facilities. Studies that show students performing better in classrooms that have the right kinds of daylighting bear out the intuitive beliefs of many…
ERIC Educational Resources Information Center
Department of Education and Science, London (England).
The application of good lighting principles to school design is discussed. Part 1 of the study is concerned with the general principles of light and vision as they affect lighting in schools. Parts 2 and 3 deal with the application of these principles to daylighting and artificial lighting. Part 4 discusses the circumstances in which the…
Energy-Efficient Schools: Three Case Studies from Oregon.
ERIC Educational Resources Information Center
2003
This document presents case studies of three schools or districts in Oregon that have implemented steps to promote energy efficiency. Steps taken by the schools include daylighting, energy audits, special energy loans, new ventilation design, and sustainable building practices. The facilities described are Ash Creek Intermediate School in…
A Proposed Astronomy Learning Progression for Remote Telescope Observation
ERIC Educational Resources Information Center
Slater, Timothy F.; Burrows, Andrea C.; French, Debbie A.; Sanchez, Richard A.; Tatge, Coty B.
2014-01-01
Providing meaningful telescope observing experiences for students who are deeply urban or distantly rural place-bound--or even daylight time-bound--has consistently presented a formidable challenge for astronomy educators. For nearly 2 decades, the Internet has promised unfettered access for large numbers of students to conduct remote telescope…
Code of Federal Regulations, 2014 CFR
2014-10-01
... of the post-test survey effort described in § 217.115. (vi) If post-detonation surveys determine that...-Surface Gunnery Missions at Eglin Gulf Test and Training Range (EGTTR) in the Gulf of Mexico § 217.114... m (1,000 ft) or greater. (v) To ensure adequate daylight for pre- and post-detonation monitoring...
Statistics for Geography Teachers: Topics in Geography, Number 2.
ERIC Educational Resources Information Center
National Council for Geographic Education.
This publication is designed to provide geography teachers with useful statistical information. It presents tables, maps, graphs, diagrams, and explanations of statistical data in 24 areas. The areas in which statistics are given are conversions, measurement, astronomy, time, daylight, twilight, latitude and longitude as distance, the relationship…
ERIC Educational Resources Information Center
Frazier, Mary Claire
2006-01-01
Some persuasive research over the past decade shows a strong relationship between the availability of daylight in classrooms and increased test scores for students. Schools seeking to apply that research to actual school construction projects face several hurdles, but the benefits can be real and long-lasting. A properly installed, calibrated and…
Shade effects on growth, flowering, and fruit of apple
USDA-ARS?s Scientific Manuscript database
Light is a critical resource needed by plants for growth and reproduction. A major portion of the apple (Malus xdomestica Borkh.) tree’s canopy is subjected to shade during most daylight hours each day and such shade may affect productivity. The current research determined effects of morning, afte...
DOT National Transportation Integrated Search
2010-04-01
Pirates prey upon targets of opportunity. Given optimal conditions (e.g., calm weather, slow cruising speed, and daylight4) relatively small, fast vessels (e.g., containerships) may be no less at risk than large, slower vessels (e.g., crude carriers)...
DETAIL VIEW OF FILTER PRESS REMAINS, BOILER, SECONDARY ORE BIN, ...
DETAIL VIEW OF FILTER PRESS REMAINS, BOILER, SECONDARY ORE BIN, TRAM TRESTLE AND WATER TANK, LOOKING NORTHWEST. HIS VIEW IS TAKEN FROM THE THIRD LEVEL OF THE MILL, NEARBY THE BLACKSMITH'S FORGE. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-01
... Limited, Kawasaki, JAPAN; Hewlett Packard Company, Palo Alto, CA; Huawei Technologies Co. Ltd., Shenzhen, PEOPLE'S REPUBLIC OF CHINA; International Business Machines Inc., Endicott, NY; Inocybe Technologies Inc...Daylight's planned activity is to (a) Advance the creation, evolution, promotion, and support of an open...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-09
... an unmitigable adverse impact on the availability of the species or stock(s) for subsistence uses... daylight hours at high tide, approaching the wharf at less than 0.75 knot (less than one mph). At least one... of [[Page 33723
77 FR 22666 - Payment System Risk Policy; Daylight Overdraft Posting Rules
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-17
... of separately-sorted savings bonds and to eliminate a reference to the contractual clearing balance... clearing balance program are effective July 12, 2012. FOR FURTHER INFORMATION CONTACT: Susan V. Foley... account balances according to a set of ``posting rules'' that determine the intraday timing of debits and...
78 FR 40434 - Meeting of the Manufacturing Council
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-05
... subcommittees. The subcommittees--Workforce and Public Perception of Manufacturing; Innovation, Research and.... Government and the manufacturing sector. DATES: July 23, 2013, 10:00 a.m.-12:30 p.m. Eastern Daylight Time... comments from members of the public attending the meeting. To accommodate as many speakers as possible, the...
Solar Glazing Tips for School Construction
ERIC Educational Resources Information Center
Smith, Jonathan
2012-01-01
Glazing can be optimized to enhance passive solar heating and daylight harvesting by exceeding the prescriptive limits of the energy code. This savings can be garnered without the high cost of external overhangs or expensive glazing products. The majority of savings from solar glazing are attributable to the increase in solar heating and…
Portable light detection system for the blind
NASA Technical Reports Server (NTRS)
Wilber, R. L.; Carpenter, B. L.
1973-01-01
System can be used to detect "ready" light on automatic cooking device, to tell if lights are on for visitors, or to tell whether it is daylight or dark outside. Device is actuated like flashlight. Light impinging on photo cell activates transistor which energizes buzzer to indicate presence of light.
OBLIQUE DETAIL VIEW OF LOWER TRAM TERMINAL, LOOKING NORTHWEST. THE ...
OBLIQUE DETAIL VIEW OF LOWER TRAM TERMINAL, LOOKING NORTHWEST. THE JAW CRUSHER FOUNDATION CAN BE CLEARLY SEEN AT CENTER LEFT WITH A CONVEYOR TO CARRY CRUSHED ORE UP TO THE SECONDARY ORE BIN,LEFT. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA
77 FR 53184 - 36(b)(1) Arms Sales Notification
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-31
..., multi-field of view EO/IR system. The system provides color daylight TV and night time IR video with a... along with ground moving target indicator (GMTI) modes. It will also have two onboard workstations that...-locate, collect, and display the relevant information to two operators for analysis and recording...
Between the Dark and the Daylight.
ERIC Educational Resources Information Center
Morneau, Robert F.
1998-01-01
Asserts that, unless we balance work and contemplation, we lose control of our lives and ourselves. Offers three ideas to return equilibrium to our lives for consideration: specificity, accountability, and expectations. Suggests specific activities, such as committing to a time-management program, as processes for reaching a harmony of action and…
Tanaka, Naoto; Delemotte, Lucie; Klein, Michael L.; Komáromy, András M.; Tanaka, Jacqueline C.
2014-01-01
Cone cyclic nucleotide-gated channels are tetramers formed by CNGA3 and CNGB3 subunits; CNGA3 subunits function as homotetrameric channels but CNGB3 exhibits channel function only when co-expressed with CNGA3. An aspartatic acid (Asp) to asparagine (Asn) missense mutation at position 262 in the canine CNGB3 (D262N) subunit results in loss of cone function (daylight blindness), suggesting an important role for this aspartic acid residue in channel biogenesis and/or function. Asp 262 is located in a conserved region of the second transmembrane segment containing three Asp residues designated the Tri-Asp motif. This motif is conserved in all CNG channels. Here we examine mutations in canine CNGA3 homomeric channels using a combination of experimental and computational approaches. Mutations of these conserved Asp residues result in the absence of nucleotide-activated currents in heterologous expression. A fluorescent tag on CNGA3 shows mislocalization of mutant channels. Co-expressing CNGB3 Tri-Asp mutants with wild type CNGA3 results in some functional channels, however, their electrophysiological characterization matches the properties of homomeric CNGA3 channels. This failure to record heteromeric currents suggests that Asp/Asn mutations affect heteromeric subunit assembly. A homology model of S1–S6 of the CNGA3 channel was generated and relaxed in a membrane using molecular dynamics simulations. The model predicts that the Tri-Asp motif is involved in non-specific salt bridge pairings with positive residues of S3/S4. We propose that the D262N mutation in dogs with CNGB3-day blindness results in the loss of these inter-helical interactions altering the electrostatic equilibrium within in the S1–S4 bundle. Because residues analogous to Tri-Asp in the voltage-gated Shaker potassium channel family were implicated in monomer folding, we hypothesize that destabilizing these electrostatic interactions impairs the monomer folding state in D262N mutant CNG channels during biogenesis. PMID:24586388
Occupant-responsive optimal control of smart facade systems
NASA Astrophysics Data System (ADS)
Park, Cheol-Soo
Windows provide occupants with daylight, direct sunlight, visual contact with the outside and a feeling of openness. Windows enable the use of daylighting and offer occupants a outside view. Glazing may also cause a number of problems: undesired heat gain/loss in winter. An over-lit window can cause glare, which is another major complaint by occupants. Furthermore, cold or hot window surfaces induce asymmetric thermal radiation which can result in thermal discomfort. To reduce the potential problems of window systems, double skin facades and airflow window systems have been introduced in the 1970s. They typically contain interstitial louvers and ventilation openings. The current problem with double skin facades and airflow windows is that their operation requires adequate dynamic control to reach their expected performance. Many studies have recognized that only an optimal control enables these systems to truly act as active energy savers and indoor environment controllers. However, an adequate solution for this dynamic optimization problem has thus far not been developed. The primary objective of this study is to develop occupant responsive optimal control of smart facade systems. The control could be implemented as a smart controller that operates the motorized Venetian blind system and the opening ratio of ventilation openings. The objective of the control is to combine the benefits of large windows with low energy demands for heating and cooling, while keeping visual well-being and thermal comfort at an optimal level. The control uses a simulation model with an embedded optimization routine that allows occupant interaction via the Web. An occupant can access the smart controller from a standard browser and choose a pre-defined mode (energy saving mode, visual comfort mode, thermal comfort mode, default mode, nighttime mode) or set a preferred mode (user-override mode) by moving preference sliders on the screen. The most prominent feature of these systems is the capability of dynamically reacting to the environmental input data through real-time optimization. The proposed occupant responsive optimal control of smart facade systems could provide a breakthrough in this under-developed area and lead to a renewed interest in smart facade systems.
Applying the Multiple Signal Classification Method to Silent Object Detection Using Ambient Noise
NASA Astrophysics Data System (ADS)
Mori, Kazuyoshi; Yokoyama, Tomoki; Hasegawa, Akio; Matsuda, Minoru
2004-05-01
The revolutionary concept of using ocean ambient noise positively to detect objects, called acoustic daylight imaging, has attracted much attention. The authors attempted the detection of a silent target object using ambient noise and a wide-band beam former consisting of an array of receivers. In experimental results obtained in air, using the wide-band beam former, we successfully applied the delay-sum array (DSA) method to detect a silent target object in an acoustic noise field generated by a large number of transducers. This paper reports some experimental results obtained by applying the multiple signal classification (MUSIC) method to a wide-band beam former to detect silent targets. The ocean ambient noise was simulated by transducers decentralized to many points in air. Both MUSIC and DSA detected a spherical target object in the noise field. The relative power levels near the target obtained with MUSIC were compared with those obtained by DSA. Then the effectiveness of the MUSIC method was evaluated according to the rate of increase in the maximum and minimum relative power levels.
Phosphor chessboard packaging for white LEDs in high efficiency and high color performance
NASA Astrophysics Data System (ADS)
Nguyen, Quang-Khoi; Chang, Yu-Yu; Lu, Chun-Yan; Yang, Tsung-Hsun; Chung, Te-Yuan; Sun, Ching-Cherng
2016-09-01
We performed the simulation of white LEDs packaging with different chessboard structures of white light converting phosphor layer covered on GaN die chip. Three different types of chessboard structures are called type 1, type 2 and type 3, respectively. The result of investigation according to the phosphor thickness show the increasing of thickness of phosphor layer are, the decreasing of output blue light power are. Meanwhile, the changes of yellow light are neglect. Type 3 shows highest packaging efficiency of 74.3 % compares with packaging efficiency of type 2 and type 1 (72.5 % and 71.3 %, respectively). Type 3 also shows the most effect of forward light. Attention that the type 3 chessboard structure gets packaging efficiency of 74.3 % at color temperature of daylight as well as high saving of phosphor amount. The color temperatures of three types of chessboard structure are higher than 5000 K, so they are suitable for lighting purpose. The angular correlate color temperature deviation (ACCTD) of type 1, type 2 and type 3 are 6500K, 11500K and 17000K, respectively.
Analysis of tethered balloon data from San Nicolas Island on 8 July 1987
NASA Technical Reports Server (NTRS)
Cox, Stephen K.; Duda, David P.; Guinn, Thomas A.; Johnson-Pasqua, Christopher M.; Schubert, Wayne H.; Snider, Jack B.
1990-01-01
Analysis of the 8 July 1987 (Julian Day 189) tethered balloon flight from San Nicolas Island is summarized. The flight commenced at about 14:30 UTC (7:30 Pacific Daylight Time) and lasted six and one-half hours. The position of the Colorado State University (CSU) instrument package as a function of time is shown. For the purpose of presentation of results, researchers divided the flight into 13 legs. These legs consist of 20 minute constant level runs, with the exception of leg 1, which is a sounding from the surface to just above 930 mb. The laser ceilometer record of cloud base is also shown. The cloud base averaged around 970 mb during much of the flight but was more variable near the end. Before the tethered balloon flight commenced, a Communications Link Analysis and Simulation System (CLASS) sounding was released at 12:11 UTC (5:11 PDT). Temperature and moisture data below 927 mb for this sounding is shown. The sounding indicates a cloud top around 955 mb at this time.
INDOOR AIR QUALITY AND INHALATION EXPOSURE - SIMULATION TOOL KIT
A Microsoft Windows-based indoor air quality (IAQ) simulation software package is presented. Named Simulation Tool Kit for Indoor Air Quality and Inhalation Exposure, or IAQX for short, this package complements and supplements existing IAQ simulation programs and is desi...
Flight simulator for hypersonic vehicle and a study of NASP handling qualities
NASA Technical Reports Server (NTRS)
Ntuen, Celestine A.; Park, Eui H.; Deeb, Joseph M.; Kim, Jung H.
1992-01-01
The research goal of the Human-Machine Systems Engineering Group was to study the existing handling quality studies in aircraft with sonic to supersonic speeds and power in order to understand information requirements needed for a hypersonic vehicle flight simulator. This goal falls within the NASA task statements: (1) develop flight simulator for hypersonic vehicle; (2) study NASP handling qualities; and (3) study effects of flexibility on handling qualities and on control system performance. Following the above statement of work, the group has developed three research strategies. These are: (1) to study existing handling quality studies and the associated aircraft and develop flight simulation data characterization; (2) to develop a profile for flight simulation data acquisition based on objective statement no. 1 above; and (3) to develop a simulator and an embedded expert system platform which can be used in handling quality experiments for hypersonic aircraft/flight simulation training.
Diurnal variation in rates of calcification and carbonate sediment dissolution in Florida Bay
Yates, K.K.; Halley, R.B.
2006-01-01
Water quality and circulation in Florida Bay (a shallow, subtropical estuary in south Florida) are highly dependent upon the development and evolution of carbonate mud banks distributed throughout the Bay. Predicting the effect of natural and anthropogenic perturbations on carbonate sedimentation requires an understanding of annual, seasonal, and daily variations in the biogenic and inorganic processes affecting carbonate sediment precipitation and dissolution. In this study, net calcification rates were measured over diurnal cycles on 27 d during summer and winter from 1999 to 2003 on mud banks and four representative substrate types located within basins between mud banks. Substrate types that were measured in basins include seagrass beds of sparse and intermediate density Thalassia sp., mud bottom, and hard bottom communities. Changes in total alkalinity were used as a proxy for calcification and dissolution. On 22 d (81%), diurnal variation in rates of net calcification was observed. The highest rates of net carbonate sediment production (or lowest rates of net dissolution) generally occurred during daylight hours and ranged from 2.900 to -0.410 g CaCO3 m-2 d-1. The lowest rates of carbonate sediment production (or net sediment dissolution) occurred at night and ranged from 0.210 to -1.900 g CaCO3 m -2 night-1. During typical diurnal cycles, dissolution during the night consumed an average of 29% of sediment produced during the day on banks and 68% of sediment produced during the day in basins. Net sediment dissolution also occurred during daylight, but only when there was total cloud cover, high turbidity, or hypersalinity. Diurnal variation in calcification and dissolution in surface waters and surface sediments of Florida Bay is linked to cycling of carbon dioxide through photosynthesis and respiration. Estimation of long-term sediment accumulation rates from diurnal rates of carbonate sediment production measured in this study indicates an overall average accumulation rate for Florida Bay of 8.7 cm 1000 yr-1 and suggests that sediment dissolution plays a more important role than sediment transport in loss of sediment from Florida Bay. ?? 2006 Estuarine Research Federation.
46 CFR 160.021-4 - Approval and production tests.
Code of Federal Regulations, 2014 CFR
2014-10-01
... stray daylight, the first test plate is illuminated by light from the specimen placed at a distance of about 1.5 m (5 ft.). The second test plate is illuminated only by light from an incandescent lamp... viewed directly, the second through combinations of Lovibond red, yellow, and blue glasses selected so as...
46 CFR 160.021-4 - Approval and production tests.
Code of Federal Regulations, 2012 CFR
2012-10-01
... daylight, the first test plate is illuminated by light from the specimen placed at a distance of about 1.5 m (5 ft.). The second test plate is illuminated only by light from an incandescent lamp operated at... viewed directly, the second through combinations of Lovibond red, yellow, and blue glasses selected so as...
46 CFR 160.021-4 - Approval and production tests.
Code of Federal Regulations, 2013 CFR
2013-10-01
... stray daylight, the first test plate is illuminated by light from the specimen placed at a distance of about 1.5 m (5 ft.). The second test plate is illuminated only by light from an incandescent lamp... viewed directly, the second through combinations of Lovibond red, yellow, and blue glasses selected so as...
ERIC Educational Resources Information Center
Mayes, Valynda
2010-01-01
In 2009, we had the year of astronomy. Even President Obama hosted an astronomy night on the White House lawn. Your explorations of nature need not be limited to daylight hours--though it is important to point our when celestial objects like the Moon are visible during the day to counter misconceptions. This year, introduce your students to the…
78 FR 72817 - Drawbridge Operation Regulation; Gulf Intracoastal Waterway, Near Moss Lake, LA
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-04
... temporarily closed to navigation during daylight for ten consecutive hours, Monday through Thursday for three weeks. DATES: This deviation is effective without actual notice from December 4, 2013 until December 19... in accordance with this subpart. The draw bridge must return to operation when the work has stopped...
BACTERIAL FLUX FROM CHAPARRAL INTO THE ATMOSPHERE IN MID-SUMMER AT A HIGH DESERT LOCATION
Estimates of the bacterial flux for a daylight cycle were observed at the Hanford Nuclear Reservation, Richland, WA, during June 1992, using a modified Bowen ratio method. he upward daytime bacterial flux was coupled with the solar radiation/sensible heat cycle, but commenced 2 h...
29 CFR 1910.145 - Specifications for accident prevention signs and tags.
Code of Federal Regulations, 2011 CFR
2011-07-01
... apply to the design, application, and use of signs or symbols (as included in paragraphs (c) through (e.... The reflective border defines the shape of the fluorescent color in daylight and creates a hollow red....D. and Collins, B.L., The Assessment of Safety Symbol Understandability by Different Testing Methods...
29 CFR 1910.145 - Specifications for accident prevention signs and tags.
Code of Federal Regulations, 2010 CFR
2010-07-01
... apply to the design, application, and use of signs or symbols (as included in paragraphs (c) through (e.... The reflective border defines the shape of the fluorescent color in daylight and creates a hollow red....D. and Collins, B.L., The Assessment of Safety Symbol Understandability by Different Testing Methods...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-21
... DEPARTMENT OF COMMERCE Bureau of Industry and Security President's Export Council; Subcommittee on... Administration (PECSEA) will meet on June 4, 2013, 9:30 a.m. (pacific daylight time), at Boeing Defense, Space and Security, Space and Intelligence Systems, Building S24, Conference Center, 2020 East Imperial...
75 FR 35801 - Meeting of the National Drinking Water Advisory Council-Notice of Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-23
... a.m. to noon, Eastern Daylight Savings Time. ADDRESSES: The meeting will be held at the Hotel... ensure adequate time for public involvement, individuals or organizations interested in presenting an... to give EPA as much time as possible to process your request. Dated: June 17, 2010. Cynthia C...
17 CFR 260.7a-4 - Calculation of time.
Code of Federal Regulations, 2010 CFR
2010-04-01
... eastern daylight-saving time, whichever is in effect at the principal office of the Commission on the date... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Calculation of time. 260.7a-4... time. Saturdays, Sundays and holidays shall be counted in computing the effective date of applications...
75 FR 35122 - Announcement of Meetings of the International Telecommunication Advisory Committee
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-21
.... Eastern Daylight Time, at 1120 20th Street, Washington, DC 20036. There will also be reports on recent... Conference). For those people outside the Washington, DC metro area, a conference bridge will be provided... 1200 Wilson Boulevard, Arlington, VA 22209. For those people outside the Washington, DC metro area, a...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-23
... (TASC) program. The intended effect of this notice is to solicit applications from the private sector... be considered for funding, applications must be received by 5 p.m. Eastern Daylight Time, May 21.... FOR FURTHER INFORMATION CONTACT: Entities wishing to apply for funding assistance should contact the...
Stepping through the Daylight Gate: Compassionate Spaces for Learning in Higher Education
ERIC Educational Resources Information Center
Haynes, Joanna; Macleod-Johnstone, Emma
2017-01-01
This paper is concerned with troubling emotions felt or aroused in all aspects of academic practice, including teaching, learning, research and relationships. It discusses the emergent processes of a research group whose multidisciplinary interests coalesce around discomfort, disturbance and difficulty in the processes of higher education. We talk…
78 FR 25289 - Board of Visitors for the National Fire Academy Teleconference
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-30
...] Board of Visitors for the National Fire Academy Teleconference AGENCY: Federal Emergency Management.... SUMMARY: The Board of Visitors for the National Fire Academy (Board) will meet via teleconference on... National Fire Academy will meet on Wednesday, May 15, 2013, from 1:30 to 4:00 p.m. Eastern Daylight Time...
STS-49 Endeavour, OV-105, landing on concrete runway 22 at EAFB, California
NASA Technical Reports Server (NTRS)
1992-01-01
STS-49 Endeavour, Orbiter Vehicle (OV) 105, glides above concrete runway 22 at Edwards Air Force Base (EAFB), California, just before main landing gear (MLG) touchdown. Nose landing gear (NLG) is also deployed during the landing sequence. Landing occurred at 1:36:38 pm (Pacific Daylight Time (PDT)).
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-29
... under USFWS's now-discontinued program, are considered non-essential experimental populations. The black... daylight hours. Additional methodological detail is available in VanBlaricom, 1993 and VanBlaricom et al..., 1987). The non-breeding distribution extends from Baja California north to Alaska for males, and...
75 FR 56158 - Industry Advisory Panel: Notice of Open Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-15
... DEPARTMENT OF STATE [Public Notice 7107] Industry Advisory Panel: Notice of Open Meeting The Industry Advisory Panel of the Bureau of Overseas Buildings Operations will meet on Thursday, October 14, 2010 from 9:30 a.m. until 3:30 p.m. Eastern Daylight Time. The meeting is open to the public and will...
76 FR 62892 - Industry Advisory Panel: Notice of Open Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-11
... DEPARTMENT OF STATE [Public Notice: 7598] Industry Advisory Panel: Notice of Open Meeting The Industry Advisory Panel of the Bureau of Overseas Buildings Operations will meet on Tuesday, October 18, 2011 from 9:30 a.m. until 3:30 p.m. Eastern Daylight Time. The meeting is open to the public and will...
75 FR 13643 - Industry Advisory Panel: Notice of Open Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-22
... DEPARTMENT OF STATE [Public Notice 6909] Industry Advisory Panel: Notice of Open Meeting The Industry Advisory Panel of the Bureau of Overseas Buildings Operations will meet on Wednesday, April 14, 2010 from 9:30 a.m. until 3:30 p.m. Eastern Daylight Time. The meeting is open to the public, as...
31 CFR 560.301 - Effective date.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Effective date. 560.301 Section 560... § 560.301 Effective date. The effective date of the prohibitions and directives contained in subpart B of this part is 12:01 a.m., Eastern Daylight Time, August 20, 1997. For the effective date of pre...