Recently, decreasing energy consumption under the premise of building comfort has become a popular topic, especially visual comfort. Existing research on lacks standard how to select indicators. Moreover, studies individual preference considering interaction between internal and external environment are few. In this paper, we ranked common indicators by cloud model combined with failure mode ef...

PURPOSE The slope of the rod threshold versus the illuminance (TVI) function changes with the wavelength of the background light. This study was conducted to determine whether the changes in slope are due to the stimulation of specific cone classes. METHODS An eight-channel optical system was used to generate lights that differed in cone and rod photoreceptor illuminance. Rod flicker TVI func...

We propose a color vision model that can be used to predict color appearance in mesopic vision as well as photopic and scotopic vision. It is based on a two-stage model which consists of the cone and opponent stages and it assumes rod intrusion at the opponent stage. The model has the following features to describe the color appearance in mesopic vision. First, it includes a gradual and nonline...

The National Institute of Standards and Technology (NIST) candela is maintained via standard photometers which have shown long-term stability of better than 0.1 % per year. The detector-based method has allowed us to reduce the uncertainties of calibrations and to expand the range of calibration capabilities. There have been several new developments in photometry at the NIST. A high-illuminance...

Objective: Reflection on visual problems in nursing homes. Data Sources: Eye examinations, documented visual problems and illuminance levels. Study design: The optometric examinations and recorded visual problems were combined with illuminance data. Data collection: In seven nursing homes, 259 residents underwent an optometric examination. Their client records were analyzed for information rega...

Generating soft shadows in real-time is difficult. Exact methods (such as ray tracing, and multiple light source simulation) are too slow, while approximate methods often over-estimate the umbra regions. In this paper, we introduce a new algorithm based on the shadow map method to quickly and accurately render soft shadows produced by a light source. Our method builds inner and outer translucen...

In this paper, a power-controllable light emitting diode (LED) control system is proposed for plant cultivation. The proposed LED system measures environmental data, such as the distance between the plant and LED system using an infrared sensor and the ambient illuminance based on an illuminance sensor. Then, it converts the illuminance to the photosynthetic photon flux density (PPFD) for plant...

Climate-Based Daylight Modelling (CBDM) methods have been validated against long-term measurements in laboratory settings and found to exhibit errors small enough make such assessments useful for daylight performance prediction. However, real occupied spaces are affected by a higher number of uncertainties than or controlled conditions. This study aims at validating CBDM collected an classroom ...

UNLABELLED BACKGROUND This paper discusses results obtained in the second monitoring campaign of the Carcer Tullianum, a particular hypogeum environment located in the historical centre of Rome (Italy). In the first paper we stressed the need to apply chemometric tools to this kind of studies in order to obtain full and significant information; really information on sampling design, sensors ...