• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.1 no.2
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• pp.49-56
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• 1987

To save energy consumption, it is proposed to operate a discharge lamp with high frequency power. When designing a high frequency operating circuit containing a discharge lamp, the character of a lamp may be needed. And there are various methods to get and models for this. In this study, to present the volt-ampere character of a fluorescent lamp which gives a good saving effect, the nonlinear resistance model is suggested. And the validity of the model is verified by applying the model for the circuits with inductor ballast and capacifor ballast. This model, in contrast with the others, can be easily obtainable. And for comparison, the model using a modified Francis equation is examined. The method used in this study can be basically applied to the other discharge lamps. As a result, 1) Approximated 3rd order polynomial of nonlinear resistance model gives a good simulation result. 2) When operating in high frequency, the model using a modified Francis equation with constant coefficients can't be applied.

• Journal of Microbiology and Biotechnology
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• v.29 no.12
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• pp.1957-1968
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• 2019

Tetraselmis is a green algal genus, some of whose species are important in aquaculture as well as biotechnology. In algal culture, fluorescent lamps, traditional light source for culturing algae, are now being replaced by a cost-effective light-emitting diodes (LEDs). In this study, we investigated the effect of LED light of different wavelengths (white, red, yellow, and blue) on the growth of Tetraselmis suecica and its associated microbial community structures using the next-generation sequencing (NGS). The fastest growth rate of T. suecica was shown in the red light, whereas the slowest was in yellow. The highest OTUs (3426) were identified on day 0, whereas the lowest ones (308) were found on day 15 under red light. The top 100 OTUs associated with day 0 and day 5 cultures of T. suecica under the red and yellow LED were compared. Only 26 OTUs were commonly identified among four samples. The highest numbers of unique OTUs were identified at day 0, indicating the high degree of initial microbial diversity of the T. suecica inoculum. The red light-unique OTUs occupied 34.98%, whereas the yellow-specific OTUs accounted for only 2.2%. This result suggested a higher degree of interaction in T. suecica culture under the red light, where stronger photosynthesis occurs. Apparently, the microbial community associated with T. suecica related to the oxygen produced by algal photosynthesis. This result may expand our knowledge about the algae-bacteria consortia, which would be useful for various biotechnological applications including wastewater treatment, bioremediation, and sustainable aquaculture.

• Journal of Biosystems Engineering
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• v.26 no.6
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• pp.571-578
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• 2001

Production of green pepper has increased for ten years in Korea, as customer's preference of a pepper tuned to fiesta one. This study was conducted to develop an on-line fading algorithm of green pepper using machine vision and aimed to develop the automatic on-line grading and sorting system. The machine vision system was composed of a professive scan R7B CCD camera, a frame grabber and sets of 3-wave fluorescent lamps. The length and curvature, which were main quality factors of a green pepper were measured while removing the stem region. The first derivative of the thickness profile was used to remove the stem area of the segmented image of the pepper. A new boundary was generated after the stem was removed and a baseline of a pepper which was used for the curvature determination was also generated. The developed algorithm showed that the accuracy of the size measurement was 86.6% and the accuracy of the bent was 91.9%. Processing time spent far grading was around 0.17 sec per pepper.

• Journal of the Korea Safety Management & Science
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• v.18 no.1
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• pp.1-8
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• 2016

This study was conducted by survey and inspection of stair passage leading lights in shopping buildings which are more than 5 stories and have an underground parking lot located at Pyeongtaek-si and Seongnam-si. Number of shopping building for this study is 30 and of stair passage leading light inspected by two lights in each shopping building is 60. The result of this study is that the type of installed leading lights is LED(77%), and 60% of leading lights has problem such as no cleaning, scratch and discoloration, etc. The height of installed leading lights meets the fire law which is less than 1m from the floor. Visible condition of leading lights is good except some leading lights which have a little visible problem due to banner advertisement. 37% of standby power has flickered and went out. 93% of total leading lights meets the fire law which is more than 1lux from 0.5m distance, but cold cathode fluorescent lamps(CCFLs) have the problem which not meets proper brightness level based on fire law. In additional measurement result, zero lux of leading lights is 32%(from 1m distance), 68%(from 1.5m distance) and 98%(from 2m distance). Leading light is very important facility because it is eyes and guide when emergency. Therefore, proper fire facility operating function inspection and total detailed inspection are important to keep the good condition of leading light except simple visual check, and also improvement in law system of type approval, fire construction inspection and illumination level will be needed.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.280-287
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• 2001

These studies aimed to determine how lighting might be used to improve feed intake and reduce aggressive behavior in newly weaned pigs. To examine whether this objective could be achieved an experiment was conducted to compare performance, behavior and body condition of weaners over 17-45 days, provided similar lighting quality (i.e. color temperature, color rendering index and lighting distribution) after weaning that piglets experienced prior to weaning. Triphosphor (TP) lighting to simulate daylight was provided during the day while at night, Pascal red (PR) lighting was provided to simulate the night-light piglets previously had received from infrared heating lamps. This treatment was compared to weaners provided conventional cool-white fluorescent light during the day only. Weaners on treatment lighting from 17-45 days of age showed no improvement in body weight or feed conversion at 24, 31, 38 and 45 days compared to the controls. There was, however, a significant improvement (p<0.05) in feed intake in the first week of weaning for weaners provided TP/PR lighting. Over the first 3 days of weaning, pigs on TP/PR lighting showed an increase (p<0.05) in the incidence of ear chewing but reduced (p<0.05) levels of nosing the abdomen of other pigs and reduced (p<0.05) occurrences of being stood on by other pigs. Females exhibited more (p<0.05) mounting and nosing behaviors and rubbing the heads of other pigs than males. On the other hand, males engaged in more (p<0.05) fighting, nipping, ear chewing and standing on other pigs compared to females. Pigs provided PR lighting on the first night of weaning engaged in higher (p<0.05) incidences of nosing and tail sucking behaviors, more (p<0.05) head thrusting, fighting and ear chewing compared to control pigs. The body condition of weaners provided the TP/PR lighting treatment was significantly poorer (p<0.05) compared to weaners on control lighting. In conclusion there was no improvement in production performance of weaners provided new technology lighting apart from the improvement in feed intake in the first week weaners were exposed to the TP/PR lighting.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.13-14
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• 2012

Than fluorescent lamps or light bulbs, long life, small power consumption and to the development of modern technology, LED (Light Emitting Diode) devices have the advantage of easy control. For these reasons, using the LED device, lighting has been widely used. LED using optical fiber technology using LED lighting technology with the development of wireless communication technology is attracting attention again. Using LED lights this study analyzed the performance of the technology transfer and implementation of the information transmission system of the visible light communication using LED lighting of the White Visible Light Communication (VLC) based PC module transmitter and receiver modules. Has made a system that can transmit information more than the value of the initial distance ~ 50cm, depending on the presence or absence of the lens, in order to increase the efficiency of the LED modules with different efficiencies that could confirm the performance of the implementation of the research, analysis, and application methods. and about the possibility that you want to check.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.21 no.1
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• pp.35-40
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• 1985

The author carried out experiments to find out the response of rock bream, Oplegnathus fasciatus (TEMMINCK et SCHLEGEL) and sea bass, Epinephelus septemfasciatus (THUNBERG) to the color nettings. The experimental water tank(180L$\times$50W$\times$55Hcm) was set up n a dark room and water level was maintained 50cm high from the bottom. The tank was devided three longitudinal sections marking 60 cm interval. The illumination systems, consisted of 20 watt fluorescent lamps and filter, were suspended adove the tank. Two different color nettings selected from five colors (red, yellow, green, blue, black) were placed in each end section of the tank. Ten fish were used in each experiment and the fish were acclimatized in the dark for 60 minutes before experiment. After the light on, the number of fish in each section of the tank was counted in every 30 seconds interval for 30 minutes. The results obtained are as follows: 1. The rock bream selected the color nettings in the order of yellow, black, blue, green and red. 2. The sea bass selected the color nettings in the order of green, black, red, blue and yellow.

• Journal of Biosystems Engineering
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• v.26 no.4
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• pp.379-384
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• 2001

To enhance the smooth graft-taking of grafted seedlings, the excessive evapotranspiration from grafted seedlings just after grafting should be avoided. A measurement system of the evapotranspiration rate of grafted seedling under artificial lighting was set up to investigate the effect of physical environment on the evapotranspiration and graft-taking characteristics of grafted seedlings quantitatively. The evapotranspiration rate of grafted seedlings affected by relative humidity and light intensity were analyzed using the measurement system. The hypocotyl of watermelons (Citrullus vulgaris cv. Sweetdew, Hungnong Seed Co.) was slantly cut and then inserted into a hole on the stem of rootstock (Lagenaria siceraria cv. FR-King, Hungnong Seed Co.). Grafted seedlings were healed and joined for 5 days under cool-white fluorescent lamps (FL20SEX-d/18, Keumho Electric Co.) with photoperiod of 12h$.$d$\^$-1/ except dark period for one day after grafting in a closed graft-taking enhancement system developed by Kim(2000). The evapotranspiration rate and graft-taking of grafted seedling at air temperature of 23$\^{C}$ and air current speed of 0.1m$.$s$\^$-1/ was highly affected by relative humidity. But light intensity showed higher effect on the stem length of scion than relative humidity. In conclusion, it was suggested that relative humidity should be controlled at higher than 90% with photosynthetic photon flux of 50$\mu$mol$.$m$^2$$.$s$\^$-1/ to increase the survival of grafted seedlings and to produce healthy seedlings.

• Korean journal of applied entomology
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• v.7
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• pp.57-59
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• 1969

Effect of light on conidial formation of Colletotrichum panacicola, C. gloeosporioides, C. runcatum and C. nicotianae was examined on potato dextrose agar on which each conidial suspension was seeded. The light source was Mitsubishi day light fluorescent lamps wi th an intensity of 100-120 ft-c at the colony surface. The treatments were (i)constant light, (ii) constant darkness, and (iii) alternating light (11hr.) and darkness {13hr.) at $26\{\circ}C\pm2$. With the exception of C. nicotianae, constant light gave the greatest sporulation over that obtained in the other two treatments; there were on significant differences in number of sporulation between under constant darkness and alternating light and darkness. C. nicotianae resulted in maximum. inter mediate and minimum sporulation under alternating light and darkness. constant darkness and constant light, respectively. These differences were statistically significant at $5\%$ level. C. truncatum and C. nicotianae produced abundant conidia in the entire test; C. gloeosporioides was intermediate, and C. panacicola was the least. Differences in number of sporulation due to light. organisms. and t he interaction of these two were all statistically significant.

• Korean journal of applied entomology
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• v.14 no.4 s.25
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• pp.205-208
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• 1975

Effect of light and temperature on the sporulation and mycelial growth by 4 strains of Mycosphaerella fragariae was examined. The light source was day light fluorescent lamps with an intensity of 2000 Lux at the colony surface. The treatment were constant light, alternating light(10hr) and darness (14h.) and constant darkness af $15^{\circ}C,\; 22^{\circ}C\; and\; 30^{\circ}C$ 1. Of the 4 strains tested, alternating light and darkness at $22^{\circ}C\;and\;15^{\circ}C$ gave the greatest sroducedtion, constant light in intermediate, constant darkness in minimum, but darkness at $30^{\circ}C$ produced abundant conidia over that obtained in the other two treatment. Differences in number of sporulation due to light, strains and the interaction of these two were all statistically significant. 2. There were not on significant differences in amount of mycelial growth due to light, but amount of mycelial growth of$S_3$ strain were the nest abundant among the 4 strains.