| Summary: | 博士 === 國立成功大學 === 電機工程學系 === 87 === Medical science studies and nursing studies have clearly demonstrated that visible light can affect the newborn infant in several ways, including effects on the type of sleep, rapid eye movement, the speed of breathing, the secretion of growth hormones and the activity of the body. These prior papers discuss timing cycles as well as intensity changes of visible light in their relation to various biological and behavioral parameters of newborn infants. However, the timing and intensity changes referred to in the prior works consider only relatively crude changes, such as light illumination levels graded "low, medium and high." They do not systematically quantify the intensity and timing factors when considering their effects on the neonatal sleeping cycle or growth process. The limits of the prior studies were published from the immaturity of visible light quantitative control techniques and the lack of integrated monitor and control systems required for practical experiments. Thus, research reports with sophisticated and systematic discussion of the neonatal growth process in relation to illumination cycles and levels have not yet been published.
To remedy the above mentioned research limitations, this paper proposes a dimming stabilization circuit using both frequency modulation and voltage modulation to make the dimming range of the fluorescent lamp wider and lets the lamp maintain a stable lighting state within the whole dimming range. A computer-based system, extended by local network for application over large areas and simultaneous experiments, for quantitative control and monitoring of visible light. In order to conquer the nonlinear characteristics of the lamp, a fuzzy lookup table control method is utilized, thereby accomplishing simple yet accurate quantitative irradiation control and light source stabilization.
With the establishment of dimming control system, the drive to the combination of the three RGB fluorescent tubes is available. Also, the assortment of different quantity of irradiation can compute the constituents of various spectrum - the visible light, needed in the studies. As for the control of duty cycles, the timing function of the microprocessor is fully utilized.
By using the timing method, the accurate control for irraditional time is performed. In order to measure the visible light in various spectrum, a low-cost color-temperature measurement method is also developed, with the use of CCD device to construct the color temperature sensor.
The experimental results indicate that our proposed method exactly achieves the goal of full measurement and control for irradiation spectrum, irradiation intensity, and the duty cycle of visible light. Through the operation of the personal computers, microprocessor and the related design of interface circuit, the visible light control and measurement system, suitable for the above mentioned studies and experiments, is developed.
|
|---|
