Theory and simulation of calculating local illuminance density based on high dynamic range panoramic maps

The development of the lighting profession toward the third stage requires our attention shifting from the light on certain planes to the light distributions in 3D spaces. In this article, we propose a practical strategy to measure the local density of illumination in 3D scenes based on the zeroth-order of spherical harmonics decompositions of a high dynamic range (HDR) panoramic map. The basic functional principle of deriving illuminance density from HDR panoramic maps was presented, and hereinafter named as illuminance panoramic. Illuminance panoramic was compared with Cuttle’s approximated illuminance scalar, which is essentially a physical approximation of the average illumination over a sphere. To verify the measurements, the average illuminance over a sphere, approximated illuminance scalar, illuminance panoramic, cylindrical illuminance, semi-cylindrical illuminance, and horizontal illuminance were simulated via a model (probe in a sphere). The results indicate that the measurement of density of illumination using HDR panoramic maps has well coincided with its definition (i.e., the average illuminance over a sphere) while other illumination values vary with how the probes are located. The measurement theories were later verified using six HDR panoramic maps of real scenes. This research provides confidence in developing applications in mobile phones by capturing HDR panoramic maps to measure the density of illumination in 3D spaces.

Analiza wpływu współ- czynników odbicia światła od powierzchni na obliczenia fotometryczne

The article presents the results of simulation tests carried out in the DIALux program concerning the influence of light reflection coefficients on photometric calculations. The analysis was made for two exemplary rooms for various purposes and for different capacities. For each of the rooms, the parameters of the calculation plane have been defined. The lighting fixtures were good depending on the work being done in each of the rooms and the height of the ceiling. The standard reflection coefficients for each room have been pre-assigned. The number of fittings and placement is planned in accordance with the lighting standard. Photometric calculations were made for different values of co-factors, while maintaining the initial values of the other two coefficients. The results obtained were compiled and compared in terms of the impact of variability of coefficients on average illumination and its uniformity. For extreme cases that do not meet the lighting standards, the optimized arrangement of the luminaires was proposed and the results obtained were presented. The research has shown that in the case of the rooms in question, the biggest influence on the results of photometric calculations has the reflectivity of light from the walls. Discrepancies between the intensity obtained in the case of smaller rooms indicate how important factor in the lighting design process is information about the planned interior design.

Estudio de las condiciones de iluminación dentro de las instalaciones de la Facultad de Ingeniería Mecánica y Eléctrica región Poza Rica – Tuxpan

Lighting is a fundamental part in the ergonomic conditioning of workstations; Although, the human being has the ability to adapt to different light conditions, the deficiency in it causes visual fatigue, which can be one of the causes for which workers make mistakes in their activities or even to cause accidents. The present work focuses on an analysis of the lighting conditions in the classrooms, laboratories and cubicles of the faculty of Mechanical and Electrical Engineering, and identify yes, the areas where the visual tasks associated with the workstations have poor lighting or excessive that causes glare, to determine what preventive or corrective measures to take, in order to achieve a safe and healthy environment for the university community. With the help of a luxometer measurements are made to calculate the average illumination (EP) and compare it with the Official Mexican Standard "NOM-025-STPS-2008, Conditions of lighting in the workplace" that establishes the maximum permissible limits ( 500 luxes). The results obtained reflect that not all the mentioned areas comply with NOM-025-STPS-2008.

Effect of Polyolefin Film and Light Transition Film on the Growth of Lettuce

In this study, effects of polyolefin(PO) film and light transition film on the growth of lettuce were investigated compared with ethylene-vinylacetate (EVA, antifogging, no drops and longevity type) film covering. Results showed that the temperature and humidity in greenhouse covered with PO film and light transition film were significantly increased. The average temperature in the greenhouse was 4 oC higher than outdoor temperature. The average illumination intensity in the greenhouse covered with PO film was 293.22 umol m-2 s-1, light transmittance was 80.37%, the average illumination intensity in the greenhouse covered with EVA film was 193.04 umol m-2 s-1, light transmittance was 52.91%. Compared with the common film, light transmittance of the PO film was significantly increased. Light transition film increased the chlorophyll content of lettuce by changing the element of the sunlight and increased production of vegetables. PO film and light transition film display a good application prospective in the production of vegetables.

KAJIAN MANAJEMEN OPTIMALISASI PENERANGAN JALAN UMUM KOTA SEMARANG

This research mainly aims to give input to Semarang Local Government in the efficiency of electricity utilization to the street illumination and the management of income tax from the societies, so they can be utilized optimally, directly, and in integrated way in order to the management of city infrastructures service. This research using the influence of traffic passenger car unit (pcu) for optimizing in a low density of traffic condition. The data of the Average Daily Traffic (ADT) volume on Pahlawan street was gathered from 6.00 p.m-6.00 a.m in every 15 minutes. The data was analyzed using quartile technique with K1 (25%) and K2 (50 %), then the researcher designed a line chart table of a link between the ADT and the time of the electricity switching on. In working days, the results are (1) the efficient time of street illumination in K1 (25%) was between 10.30 p.m-3.45 a.m, (2) in K2 (50%) was between 9.45 p.m-4.30 a.m. Due to the security and the beauty of the town and also considering the density of the traffic, the optimization and the dimming of the electricity are not needed in holidays. The optimization using ballast dimming (40%) from 250 watt to 150 watt for all lamps, obtained a significant account 32,4 Lx for average illumination. It is still fulfill the minimal requirement of 7 Lx for the average illumination on the collector street type. The optimization with dimming system obtained an efficiency in K1 (25%) was 23.16% and in K2 (50%) was 25,05%. Kajian ini bertujuan untuk memberi masukan kepada Pemerintah Kota Semarang dalam rangka efisiensi penggunaan daya listrik untuk penerangan jalan umum dan pengelolaan pendapatan pajak dari masyarakat. Kajian ini menggunakan pengaruh dari kepadatan lalu lintas jalan dalam satuan mobil penumpang (smp), guna optimalisasi penerangan jalan umum dalam kondisi kepadatan lalu lintas jalan yang rendah. Data Volume Lalu lintas Harian Rata-rata (LHR) Jalan pahlawan dilakukan dari jam 18.00 sore hari, hingga 06.00 WIB pagi dengan pencatatan per 15 menit, kemudian dibuat tabel grafik garis hubungan antara LHR dengan waktu penyalaan lampu penerangan jalan umum Kota Semarang, pada hari kerja diperoleh : (1) waktu efisiensi penyalaan lampu pada K1 (25%) antara jam 22.30 sampai dengan 03.45 Wib, (2) waktu efisiensi penyalaan lampu pada K2 (50%) antara jam 21.45 sampai dengan 04.30 Wib. Sedangkan pada hari libur berdasarkan keamanan dan keindahan kota serta volume lalulintas kendaraan yang cukup padat maka tidak ada perlakuan optimalisasi peredupan. Optimalisasi dengan sistem peredupan ballast (40%) dari daya 250 watt menjadi 150 watt pada seluruh titik lampu penerangan, didapat perhitungan kuat penerangan rata-rata sebesar 32,4 Lx, dan masih memenuhi syarat minimal kuat penerangan rata-rata untuk jenis jalan kolektor sebesar 7 Lx. Sistem optimalisasi dengan peredupan diperoleh efisiensi pada K1 (25%) sebesar 23,16 % dan K2 (50%) sebesar 25,05%..

3D Kirchhoff prestack time migration in average illumination-azimuth and incident-angle domain for isotropic and vertical transversely isotropic media

Conventional offset domain prestack migration tends to bring ambiguity and migration artifacts because it smears energy from different angles at the image point. To avoid this, prestack depth migration implementations in angle domain have been investigated in the past decades. As an efficient imaging tool, angle domain Kirchhoff prestack time migration is still useful and was proposed recently. However, existing algorithms cannot handle ray bending and anisotropy correctly. Practically, azimuth analysis for fractured reservoirs should be carried out after migration for most geological settings. Unfortunately, the existing migration algorithm implicitly involves some kind of binning to source-receiver azimuth, which may not be the real wave-pathazimuth, especially for side-scattering or out-of-plane waves. In this paper, we present an algorithm for 3D Kirchhoff prestack time migration in average illumination azimuth and incident angle domain, which matches true wave path naturally and more accurately. To handle ray bending and vertical transversely isotropy, we propose several approaches to estimate two-way traveltime and the corresponding angular attributes through extended offset-to-angle mapping. Based upon these approaches, our 3D prestack time migration can provide high-quality common-image gathers for amplitude variation with incident angle and/or amplitude variation with offset and azimuth analyses, even in media with slight to moderate lateral heterogeneity. The 2D and 3D synthetic examples prove the validity of our methods.

Fabrication of Light Guiding Plate of Double-Side Hot-Embossing

Generally, the light guiding plate is fabricated by injection molding. Polymethyl methacrylate (PMMA) material is used to fabricate the light guiding plate. In order to reduce the space of backlight, the light guiding plate is based on double-side microstructures by using MEMS and hot-embossing technologies. From the experimental results, the minimal illumination is 355 lux and the average illumination is 368.1 lux, the uniformity of illumination is 0.08. The novel integrated light guiding plate is achieved a uniformity of distribution, without any optics sheets. In this paper, non-prism LGPs, micro-prism LGPs, and the double-side hot embossing LGPs are fabricated.