• Journal of Bio-Environment Control
• /
• v.27 no.4
• /
• pp.400-406
• /
• 2018

In this experiment the effect of supplemental lighting on the growth and yield of cucumber (Cucumis sativus L. 'Fresh') plants during low radiation period of winter season were investigated in glasshouses using common high-pressure sodium (HPS) lamps and newly developed plasma lighting system (PLS) lamps. Plants grown without supplemental lighting were considered as a control. Supplemental lighting was provided from November 20th, 2015 to March 15th, 2016 to ensure 14-hour photoperiod (natural+supplemental light), also lamps were operated automatically when the outside sun radiation levels were less than $100W{\cdot}m^{-2}$. Spectral analysis showed that HPS lamp had a discrete spectrum, lacked of the radiation in the 400-550 nm wave band (blue-green light), but had a high output in the orange-red region (550-650 nm). A higher red light output resulted in an increased red to far-red (R/FR) ratio in HPS lamp. PLS had a continuous spectrum and had a peak radiation in green region (490-550 nm). HPS has 12.6% lower output in photosynthetically active radiation (PAR) but 12.6% higher output in near infra-red (NIR) spectral regions compared to PLS. Both HPS and PLS lamps emitted very low levels of ultra-violet radiation (300-400 nm). Supplemental lighting both from HPS and PLS lamps increased plant height, leaf number, internode number and dry weight of cucumber plants compared to control. Photosynthetic activity of cucumber plants grown under two supplemental lighting systems was comparable. Number of fruits per cucumber plant (fruit weight per plant) in control, PLS, and HPS plots were 21.2 (2.9 kg), 38.7 (5.5 kg), and 40.4 (5.6 kg), respectively, thereby increasing yield by 1.8-1.9 times in comparison with control. An analysis of the economic feasibility of supplemental lighting in cucumber cultivation showed that considering lamp installation and electricity costs the income from supplemental lighting increased by 37% and 62% for PLS and HPS lamps, respectively.

• Journal of Korean Academy of Nursing
• /
• v.35 no.1
• /
• pp.143-153
• /
• 2005

Purpose: This study was aimed at finding the effects of cycled lighting on body weight, physiological variables and the behavioral state of LBWI (low birth weight infants) in the NICU. Method: The subjects were 20 LBWI at 2 NICUs. They were assigned to an experimental or control group which consisted of 10 subjects in each. Cycled light was applied to the experimental group for 10 days. Result: It was certified that the application of cycled lighting resulted in increased body weight and O2 saturation, and decreased heart rate of the LBWI. However, there was no effect in decrease of respiration and stabilization of the behavioral state. Conclusion: The application of cycled lighting might be a nursing intervention which would in turn have positive effects on the growth of LBWI.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2000.11c
• /
• pp.586-592
• /
• 2000

There is currently no satisfactory way to optimize supplemental lighting in a greenhouse-type plant factory especially concerning plant production. In a commercial plant factory, we got outside radiation data, inside radiation data and lamp running data. They have a correlation, but have much disorder. By using regression, tendency between the outside and the inside including supplemental lighting was found. We could estimate the average transmittance of this plant factory. From this estimation, we could admit the amount of inside radiation was supplied as much supplied compared to natural radiation. Then we are trying to investigate of the production amount and the supplemental lighting. Plant factory is environmentally controlled, the temperature and humidity are not actually controlled stable. We propose a design of neural network model could be useful to estimate the profit resulting from the operation of supplemental lighting.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2009.10a
• /
• pp.169-172
• /
• 2009

Daylight responsive dimming system, which is one of the method for utilizing available daylight. continuously adjusts lighting output with an algorithm of the correlation of photosensor signal and workplane illuminance levels. This system must be related with shading systems which are to control penetrating daylight. The purpose of this research is to analyze illuminance distributions by artificial lighting in different shading systems. Lighting power is changed by 5 levels in nighttime for comparing correlation between illuminance and lighting power in different shading systems.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2001.11a
• /
• pp.31-34
• /
• 2001

Changing to a 24-hour urbanistic life style, a night time activities constituted for a major portion. Important of a beautiful exterior lighting as well as safety, and security concerns become increasingly. However, the removal or control of the excessive lighting is considered more important then increasing the brightness of the lamps to achieve bother safety and security. Representing a cheerful and leisure environment from the exterior lighting can also harmonize two aspects of energy saving and sustaining green environment. Designing of exterior lighting at the ＯＯ Agricultural & Fishery Circulation center symbolizes the suitability, convenience and production. It's design and analysis represent the optimum urban night time environment.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.61 no.1
• /
• pp.18-22
• /
• 2012

In this paper, we propose a sensor-based LED lighting system that can significantly reduce standby powers. The proposed LED lighting system has the more advanced power circuit and control mechanism compared to existing one. The whole power circuit consists of two subcircuits. One is designed to apply electric powers to controller, PIR(Pyroelectric Infrared Ray) sensor and CdS, and the other one is designed to apply electric powers to LED module. Such a power circuit configuration makes the standby powers reduction of LED lighting system possible. From the experimental results, we confirmed that the standby powers saving performance of the developed power circuit is superior to that of the conventional one.

• Proceedings of the KIEE Conference
• /
• 1999.07e
• /
• pp.2423-2425
• /
• 1999

During the last years demands for higher visual comfort, flexibility of the lighting system in new type of office structures, especially intelligent building, and compatibility with work at VDU place increased. At the same time better lighting conditions should be realized by energy-effective system leading to less consumption of energy. In the intelligent building need the now type of lighting control system, also it should be included for a human-sensibility. It is shown that when designing lighting for intelligent building, greater importances should be attached to the creation of a well-balanced luminance distribution in the field and research for the people by the Ergonomics Planning.

• Journal of the Optical Society of Korea
• /
• v.16 no.3
• /
• pp.203-209
• /
• 2012

Visible light communications (VLC) use modern solid-state light-emitting diodes (LEDs) to broadcast information. Emerging white-light LEDs allow the combination of lighting and optical wireless communication in one optical source. In this paper, a new LED lighting design using one-chip-type white LEDs is proposed for efficient illumination and optical wireless communications under the existence of several obstacles. Lighting and communication performance are analyzed to show the effectiveness of the proposed LED lighting. Specifically, the signal-to-noise ratio considering intersymbol interference and the bit-error rate of variable pulse position modulation (VPPM) with dimming control are considered.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.27 no.7
• /
• pp.1-7
• /
• 2013

LED lamps are appropriate to the light source for use in broadcasting lighting. When the lighting frequency of LED lamp is different from the shutter frequency of camera, however, the flicker appears on the moving image which is taken by the camera under the dimmed light of LED lamp with conventional dimming methods. In this study, a new dimming method for the LED lamps used as the broadcasting lighting is proposed to minimize the flicker. A lighting period in the proposed dimming method is divided into the several sub-periods which have weight of the bits. Also, the proposed dimming method has characteristics that are optimizing the turn-on timings of two LED lamps to reduce the turn-off periods of the lamps and not to overlap the turn-on periods of the lamps. In the experiments, the incidence of the flicker is taken by the camera under several lighting conditions of the conventional dimming methods and the proposed dimming method. In addition, the brightness values of the frames are obtained in the moving image, and incidence of the flicker is evaluated and compared with conventional methods. From the results, the incidence of the flicker in the proposed method is more improved than the conventional methods.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2011.05b
• /
• pp.99-104
• /
• 2011

Daylighting system is an alternative to the energy crisis and environment change. And it is possible improvement system of Architectural Space Environment. Accordingly, it is very useful system. Because Daylight Duct System of Daylighting System gives high performance for its price, distribution rate is very high. But Daylighting Duct System is hard to accurate control. Accordingly, it is difficult to maintain continuously Daylight Environment in Interior Spaces. Lighting Diffusion System has been developed that it is Applying the principle of Reflector and prism diffuser for maximize the efficiency of lighting of Daylight Duct Systems through this study. And then compare lighting performance of Existing System and new Lighting Diffusion System through producing a mock-up. Thus, this study was carried out for the purpose of verification for excellence. It is that installed Each Daylighting Duct System for performance evaluation in a laboratory of width 4m, length 10m, height 2.5m. And illuminance was measured at noon on winter solstice(December 22) under clean sky. The actual measurement result was in the following. Newly developed lighting Diffusion system was measured maximum illuminance 399, minimum illuminance 221, average illuminance 141. Synthetically, daylight factor, uniformity factor and illuminance distribution were improved more than existing system. As a result, it was confirmed that was improved lighting Environment in Interior Spaces.