This paper offers a novel algorithm to better design LEDs arrays for illumination systems. First, the illuminance distribution of LED arrays is studied through theoretical analysis. Second, we present the algorithm criterion and steps. And finally, we use computer to simulate and verify this method. The results show that the illumination uniformity is significantly affected by the spacing of ea...

Technology has become an essential part in every aspect of our lives. However the key to a successful implementation of a technology depends on the acceptance by the general public. In order to increase the acceptance various approaches can be applied. In this paper, we will examine the humanrobot emotional interaction by investigating the capabilities of a developed low-resolution RGB-LED disp...

White-light emitting diode lamps for general illumination can be realized by a combination of a blue light-emitting diode semiconductor die and phosphors. Newly developed oxynitride and nitride phosphors are promising candidates for this application because they have suitable excitation and emission wavelengths and stable optical properties in a high temperature environment. High brightness war...

The useful life of an LED is presently determined by the IESNA LM80-08 lumen maintenance standard. Even though an LED system has many components, the current industry practice rates LED system lifetime based on a single component, namely, the LED. LED system life is one of the least understood parameters, especially in application environments. As a result, any lifetime claim for a complete LED...

This study aims to evaluate the effect of LED lighting during incubation of Fayoumi eggs on hatchability and hatch chick performance. The experiment was carried out in three groups with total number of 2100 eggs. Eggs were incubated 24 h of complete darkness (G1); 24 h of complete LED lighting (G2); and 12 h of LED lighting then 12 h of darkness (G3). From the obtained results, there were no ef...

This paper presents the design and develops of voltage acceptability curves for LED lamps. It is done with the mathematical representation of DC bus voltage of LED lamps internal ballast circuit during voltage sags. First, experimental analysis was done to determine the effect of voltage sag of LED lamp. From the findings on the variation of DC bus voltage during voltage sag, a mathematical equ...

This paper introduces display design process about hardware and software based on AT89C52 single chip microcomputer. We use a simple external circuit to control the display screen, which size is 32 × 192. The display screen also can display the size of the six 32 × 32 dot matrix Chinese characters by a dynamic scan mode, and can be divided into two small display screen, which can display twenty...

A portable instrument for oxygen determination, based on the quenching of phosphorescent octaethylporphyrin by gaseous O(2), has been developed using the fluorimetric paired emitter-detector diode technique (FPEDD). The instrument configuration consists of two light-emitting diodes (LEDs) facing each other, with an interchangeable support containing a phosphorescent membrane in between, in whic...