Efektivitas Daylight Mirror Shaft sebagai Sistem Pencahayaan Alami Ruang Bawah Tanah pada Langit Tropis

Title: Effectiveness of Daylight Mirror Shafts as Natural Daylighting System for Basements under Tropic Sky Conditions Basements have lots of potential as functional spaces, but have mostly been neglected due to lighting issues. Therefore, this study will explore the daylight mirror shaft system as a daylight strategy for basements, which features the placement of a reflecting surface on a light shaft to redirect daylight. The system was introduced by Heliobus®, a daylighting company from Switzerland. To see the effectiveness of implementing the system in Indonesia, a study was made on its performance on the climate sky condition. Furthermore, a study was made on the effect of different opening orientations and light shaft placements toward the illuminance level achieved. The lighting data was obtained using the simulation softwares Lightstanza. Results show that the performance of the system on climate sky condition can provide sufficient light for 41% of a basement. The use of mirrors on the light shaft could also increase the lighting levels by 2.1 times compared to a shaft without a mirror. Moreover, it was found that different opening orientations and light shaft placements didn’t give a significant effect on the lighting quantity. Overall, the study shows that the system’s implementation on climate skies still require adjustments through further studies to be effective.

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Influence of scale on the daylighting system evaluation in physical models: Experimental method based on objective and subjective measurements

Journal of Physics Conference Series ◽

10.1088/1742-6596/2042/1/012121 ◽

2021 ◽

Vol 2042 (1) ◽

pp. 012121

Author(s):

Safa Daich ◽

Mohamed Yacine Saadi ◽

Barbara E.A Piga ◽

Ahmed Motie Daiche

Keyword(s):

Physical Model ◽

Scale Effects ◽

Physical Models ◽

Subjective Evaluations ◽

Test Models ◽

Scale Models ◽

Measurement Results ◽

Illuminance Level ◽

Survey Results ◽

Sky Conditions

Abstract The daylight evaluation in architectural spaces can be carried out using several tools and methods of investigation and analysis. However, many types of research have proven the usefulness of the scale models to evaluate daylighting system performances in buildings. Several scales of a physical model have been used varying between (1:50) and real scale (1:1), and no comparative study has been done to evaluate the effect of the model size in daylighting assessment. The objective of this investigation is to make a comparison between two different scales of a physical model: the first one is a model with a scale of (1:12) while the second is with the scale of (1: 4), aiming to study the scale effects on daylight perception with models equipped with a daylighting system under very high exterior illuminance levels. The methodology of this study consists in collecting simultaneously the measurement of the exterior and interior illuminance level (lux) and subjective evaluations from a questionnaire survey with the two scale models (1:4 and 1:12) under real sky conditions. A correlation between collected data has been explored. Comparing the measurement results, it is obvious that the quantity of light that penetrates the test models (1:4 and 1:12) was the same. The results are with a range of ±1.6%. Moreover, survey results show that the participants’ perceptions regarding satisfaction, light distribution and glare questions differ with the scale of the physical 3D model. The subjects felt more satisfied with the luminous atmosphere with the physical model of (1:4) compared with the model of (1:12).

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Partial Daylight Autonomy (DAp): A New Lighting Dynamic Metric to Optimize the Design of Windows for Seasonal Use Spaces

Applied Sciences ◽

10.3390/app11178228 ◽

2021 ◽

Vol 11 (17) ◽

pp. 8228

Author(s):

Alejandro Ruiz ◽

Miguel Ángel Campano ◽

Ignacio Acosta ◽

Óscar Luque

Keyword(s):

Energy Consumption ◽

Natural Light ◽

Indoor Space ◽

Lighting Control ◽

Simulation Process ◽

Illuminance Level ◽

Sky Conditions ◽

The Impact ◽

Dynamic Metrics ◽

Accurate Indicator

Nowadays, daylight dynamic metrics are the most useful indicators to quantify the use of natural light, with daylight autonomy (DA) being one of the most widespread among all of them. This metric represents the percentage of the occupied time throughout the year in an indoor space when daylight reaches the minimum illuminance level to develop a specific task. Accordingly, the higher the percentage of DA, the shorter the switching on time of electric lighting. However, this metric considers for its calculations all business days of a whole standard year, and is thus not an accurate indicator for seasonal use spaces such as school classrooms. In this context, a variant of this metric is proposed, namely partial daylight autonomy (DAp), which is a non-lineal derivation of DA that considers those seasonal use spaces, helping to define the real percentage of indoor daylight use in order to properly quantify the accurate switching on time of electric lighting and therefore its energy consumption. As deduced from the analysis, the more precise results provided by DAp reach divergences close to 10% in comparison with the original conception of DA. Thus, this metric serves to estimate more accurately the impact on energy consumption if an electric lighting control system is implemented through lux meters. This new proposal has been monitored under real sky conditions in a test cell, providing converging results with those observed in the simulation process.

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Illuminance levels based on different sky conditions by considering daylight harvesting

Indonesian Journal of Electrical Engineering and Computer Science ◽

10.11591/ijeecs.v19.i3.pp1219-1225 ◽

2020 ◽

Vol 19 (3) ◽

pp. 1219

Author(s):

Nik Sahidah Nik Ahmad ◽

N. H. Radzi ◽

Mohd Noor Abdullah

Keyword(s):

Energy Consumption ◽

Greenhouse Effect ◽

Weather Conditions ◽

Lighting System ◽

Artificial Lighting ◽

Harvesting Systems ◽

Illuminance Level ◽

Sky Conditions ◽

Daylight Harvesting ◽

Overcast Sky

Daylight Harvesting Systems (DHS) offer the most effective and significant to reduce energy consumption. In the lighting system, there are various problems which include waste of energy consumption, inappropriate lighting and increasing greenhouse effect. Therefore, the waste of energy consumption should be reduced by controlling the dimming levels of artificial lighting according to the standard thus reducing the greenhouse effect. Hence, this paper considered the daylight adaptive for the lighting system to determine the dimming level and illuminance level for the office room. The simulation has been carried out using DIALux simulation lighting software to simulate the average daylight and average illuminance level with different conditions sky, which is clear, average, and overcast sky. Based on the result, the illuminance level has complied with the European Standard EN12464-1. Furthermore, the presence of daylight and weather conditions plays an essential role in the lighting system. The illuminance and dimming levels are different depending on the time and type of sky condition at that time. Therefore, the daylight adaptive in the lighting system can reduce the use of artificial light in the room.

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A Comparative Study on Daylight Performance Assessment of Light Shelves Based on Inclination

Mehran University Research Journal of Engineering and Technology ◽

10.22581/muet1982.2004.12 ◽

2020 ◽

Vol 39 (4) ◽

pp. 800-805

Author(s):

Sadaf Noshin ◽

Humaira Kanwal ◽

Abrar Ahmad

Keyword(s):

Control Strategies ◽

Design Parameters ◽

Winter Solstice ◽

Lighting Control ◽

Control Scheme ◽

Superior Effect ◽

Illuminance Level ◽

Daylight Performance ◽

Sky Conditions ◽

Overcast Sky

Energy consumption of lighting can be reduced by using different daylight control strategies. The rise in environmental distresses requires the necessity of natural light control systems. Light shelf is considered as excellent lighting control scheme that provides great lighting production and inexpensive prospect via entering the daylight inside the space. The aims of this study shows that the daylight efficiency and visual productivity are affected by the design parameters of light shelf such as its angle, location and height. In this research, Autodesk Ecotect 2011 is used for the daylight simulation of summer solstice and winter solstice days under overcast sky conditions on a nominated theoretical study space of an institutional building. Daylight simulation is carried out to evaluate the illuminance requirement within the selected space and analysis is also executed on the model with selected categories of light shelves including different positions, heights and angles. The acquired data is then exported on Radiance software intended for complete day-light investigation. The results of this research shows that external light shelf at a height of 7' and an angle of 20˚ is the most appropriate choice in prevailing the glare and it also enhanced the illuminance level to11.5% in 21st June and 10.6% in 21st December as compared to without light shelves. Furthermore, the shaded range is decreased by the rise in the angle of Light shelf which has a tendency to increase the inside average lighting. Hence, significant consideration should be given to the height and position of light shelves, since it has a superior effect on light shelf performance.

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Evaluation of net shortwave radiation over China with a regional climate model

Climate Research ◽

10.3354/cr01598 ◽

2020 ◽

Vol 80 (2) ◽

pp. 147-163

Author(s):

X Liu ◽

Y Kang ◽

Q Liu ◽

Z Guo ◽

Y Chen ◽

...

Keyword(s):

Regional Climate Model ◽

Climate Model ◽

Regional Climate ◽

Radiant Energy ◽

Energy System ◽

Radiation Budget ◽

Shortwave Radiation ◽

Monsoon Region ◽

Clear Sky ◽

Sky Conditions

The regional climate model RegCM version 4.6, developed by the European Centre for Medium-Range Weather Forecasts Reanalysis, was used to simulate the radiation budget over China. Clouds and the Earth’s Radiant Energy System (CERES) satellite data were utilized to evaluate the simulation results based on 4 radiative components: net shortwave (NSW) radiation at the surface of the earth and top of the atmosphere (TOA) under all-sky and clear-sky conditions. The performance of the model for low-value areas of NSW was superior to that for high-value areas. NSW at the surface and TOA under all-sky conditions was significantly underestimated; the spatial distribution of the bias was negative in the north and positive in the south, bounded by 25°N for the annual and seasonal averaged difference maps. Compared with the all-sky condition, the simulation effect under clear-sky conditions was significantly better, which indicates that the cloud fraction is the key factor affecting the accuracy of the simulation. In particular, the bias of the TOA NSW under the clear-sky condition was <±10 W m-2 in the eastern areas. The performance of the model was better over the eastern monsoon region in winter and autumn for surface NSW under clear-sky conditions, which may be related to different levels of air pollution during each season. Among the 3 areas, the regional average biases overall were largest (negative) over the Qinghai-Tibet alpine region and smallest over the eastern monsoon region.

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LIGHTING AND PERFORMANCE: AN ANALYSIS ON LIGHTING EFFICIENCY OF ARCHITECTURE STUDIO

Malaysian Journal of Sustainable Environment ◽

10.24191/myse.v1i1.5563 ◽

2019 ◽

Vol 1 (1) ◽

pp. 92

Author(s):

Fazidah Hanim Husain

Keyword(s):

Learning Environment ◽

Comfort Level ◽

Artificial Lighting ◽

Level Measurement ◽

Acceptable Range ◽

Creative Learning ◽

Illuminance Level ◽

And Performance ◽

Effect Of Light

Lighting is one of the key elements in any space and building infrastructure. Good design for an area in the building requires sufficient light that contributes to the efficiency of the activities. The correct method allows natural light to transmit, reduce heat and glare in providing a conducive learning environment. Light plays a significant influence to the quality of space and contributes focus of the students in an architecture studio. Previous research has shown that the effect of light also controlled emotions, behavior, and mood of the students. The operations of artificial lighting that have been used most of the time in an architecture studio during day and night may create lavishness and inadequacy at the same time. Therefore, this paper focuses on the identifying the quality of light for the architecture studio in UiTM (Perak), to instill a creative learning environment. Several methodologies adopted in this study such as illuminance level measurement using lux meter (LM-8100), and a questionnaire survey in gauging the lighting comfort level from students’ perspective. The study revealed that the illuminance level in the architecture studio is insufficient and not in the acceptable range stated in the Malaysian: Standards 1525:2007 and not evenly distributed. The study also concluded that the current studio environment is not condusive and appears monotonous.

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DETERMINATION OF THE MINIMAL REFLECTING SURFACE POINTS NUMBER REQUIRED FOR ASSESSMENT OF LARGE-SIZE TRAN SFORMABLE ANTENNA PATTERN DEVIATION

Siberian Journal of Science and Technology ◽

10.31772/2587-6066-2018-19-1-66-75 ◽

2018 ◽

Vol 19 (1) ◽

pp. 66-75

Author(s):

G.I. Kalabegashvili ◽

◽

E.V. Bikeev ◽

M.G. Mathylenko ◽

◽

...

Keyword(s):

Antenna Pattern ◽

Large Size ◽

Pattern Deviation ◽

Reflecting Surface

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Active control of the scattered radiation with a reflecting surface

Noise Control Engineering Journal ◽

10.3397/1/376717 ◽

2019 ◽

Vol 67 (3) ◽

pp. 190-196

Author(s):

Ning Han

Keyword(s):

Control System ◽

Active Control ◽

Scattered Radiation ◽

Sound Pressure ◽

Sound Field ◽

Control Area ◽

Mirror Image ◽

Three Dimension ◽

Control Effect ◽

Reflecting Surface

Based on a prediction method of the scattered sound pressure, an active control system was proposed in previous work for the three-dimension scattered radiation, where all the relevant simulations and experiments were implemented in three-dimensional free sound field. However, for practical applications, such as the anti-eavesdropping system or the stealth system for submarines, the sound field conditions are usually complex, and the most common case is the one with reflecting surface. It is questionable whether the previous control system is still effective in non-free sound field, or what improvements should be operated to ensure the control effect. In this article, based on the mirror image principle, two methods of calculating the control source strengths are proposed for the scattered radiation control, and numerical simulations with one-channel and multi-channel system are implemented to detect the corresponding control effect. It is seen that the local active control for the scattered radiation is still effective, and the reduction of the sound pressure level as well as the control area is extended with the increasement of the error sensors and control sources.

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Soil and ecological division into districts of the Baikal region

Geodesy and Cartography ◽

10.22389/0016-7126-2018-940-10-54-64 ◽

2018 ◽

Vol 940 (10) ◽

pp. 54-64 ◽

Cited By ~ 1

Author(s):

I.A. Belozertseva ◽

A.A. Sorokovoj

Keyword(s):

Baikal Region ◽

Soil Cover ◽

Soil Formation ◽

Forest Steppe ◽

Leading Role ◽

Soil Cover Structure ◽

Reflecting Surface ◽

Heat And Moisture ◽

Made In

On the basis of long-term researches of soils in the territory of Russia and Mongolia soil and ecological division into districts of the Baikal region is carried out. At division into districts the whole set of an environment of soil formation was considered. On the map of soil and ecological division into districts 13 mountain, mid-mountain, low-mountain taiga, foothill, hollow-valley, forest-steppe and steppe provinces reflecting surface device originality as the ratio of balance of heat and moisture forming a basis to zoning is shown against the background of difficult orography are allocated. In total 42 districts on lithologic-geomorphological features are allocated. In formation of distinctions of a soil cover of these provinces the leading role is played by bioclimatic factors and inside them the lithologic-geomorphological ones. In the view of structural approach of the district they are considered as territories with a certain natural change of several types of the soil cover structure caused by features of a relief and the parent rock. The map is made in the MapInfo program. It is revealed that on ill-defined width zoning of soils the vertical one which has a greater influence on soils of this region is imposed. Soils of the Baikal region are not similar to the soils located at the same latitude of the flat European territory of Russia. Zone soils of this territory are specific and original.

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