• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.49 no.4
• /
• pp.385-394
• /
• 2013

This study has conducted a comparative analysis on the fishing efficiency of LED fishing lamps by squid jigging vessels, the Yeongrak-ho (16 tons) and Somang-ho (9.77 tons), which operated during September and October 2010 and during October 2011, comparing with MH (Metal Halide) fishing lamp-equipped fishing vessels. This study has also examined vessel's fuel consumption level. The light powers of LED fishing lamps of the Yeongrak-ho and Somang-ho were 25.8kW and 32kW, respectively. Those of the MH fishing vessels, that is, the MH fishing lamp-equipped fishing vessels, were 105kW and 81kW, respectively. The average squid catch in number of an LED vessel, Yeongrak-ho, was 39.2% of the MH fishing lamp-equipped fishing vessels; however, that of the Somang-ho improved to 78.7% of the MH fishing lamp-equipped vessels. Average catch in number by Yeongrak-ho crew was 2.6 times more than catch in number by automatic jigging machines. Average catch in number by MH fishing vessel crew was 1.8 times more than that by automatic jigging machines. An LED vessel, Yeongrak-ho's fishing rate was 17.5%~152.2% of the MH fishing vessels, that is, 61.1% on average, in comparison of combined catch in number per automatic jigging machine and per crewmember. Somang-ho's fishing rate was 6.7%~127.6% of the MH fishing vessels, that is, 73.1% on average. The average fuel consumption level of the Somang-ho, throughout its departure from to arrival at the port, was 475.7l, and that during fishing hours was 109.6l, or 23.0% of the total fuel consumption level. Somang-ho's fuel consumption level per fishing hour was 9.7l on average.

• Journal of Bio-Environment Control
• /
• v.22 no.4
• /
• pp.400-407
• /
• 2013

This study was performed to analyze the effect of light quality of discharge lamp on growth and phytochemicals contents of lettuce (Lactuca sativa L. cv. Jeokchima) grown under metal halide (MH) lamp, high-pressure sodium (HPS) lamp, and xenon (XE) lamp in a plant factory. Cool-white fluorescent (FL) lamp was used as the control. Photoperiod, air temperature, relative humidity, $CO_2$ concentration, and photosynthetic photon flux (PPF) in a plant factory were 16/8 h (day/night), $22/18^{\circ}C$, 70%, 400 ${\mu}mol{\cdot}mol^{-1}$, and 200 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively. MH lamp had the greatest fraction of blue light (400-500 nm) of 23.0%. However, HPS lamp had the lowest fraction of 4.7% for blue light and the greatest fraction of 38.0% for red light (600-700 nm). At 11 and 21 days after transplanting, leaf length, leaf width, leaf area, shoot fresh weight, and shoot dry weight of lettuce as affected by the light quality of the discharge lamp were significantly different. The leaf area of lettuce grown under HPS, MH, and XE lamp increased by 45.7%, 16.3%, and 9.5%, respectively, as compared to the control. These results were similar for shoot fresh weight. Growth characteristics of lettuce grown under HPS lamp increased since HPS lamp had more fraction of red light. However, growth of lettuce grown under MH and XE lamp decreased since they had more fraction of blue light. As compared to the control, the ascorbic acid in lettuce leaves grown under discharge lamp decreased. The greatest anthocyanins accumulation of 0.70 mg/100 g was found at MH treatment. Anthocyanins content in lettuce leaves grown under XL and HPS lamp were 79.3% and 8.6%, respectively, compared with the control. Growth and phytochemicals contents of lettuce were highly affected by the different spectral distribution of the discharge lamp. These results indicate that the combination of discharge lamp or LED lamp for enhancing the light quality of discharge lamps is required to increase the growth and phytochemicals accumulation of lettuce in controlled environment such as plant factory.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.50 no.3
• /
• pp.326-333
• /
• 2014

This study was conducted to investigate the fishing efficiency of an improved LED fishing lamp for squids. A total of 31 fishing operations were carried out with six-crew commercial fishing vessel Haengbok-Ho (24 tons) on which 43.2kW LED was installed, along with 14 automatic jigging machines, from October 6 to November 16, 2012. The 19 fishing vessels with Haengbok-Ho were compared with a control subject was 24 tons or 29 tons. A total illuminating power of metal halide (MH) fishing lamps in the control fishing vessel was either 84kW or 120kW. The number of automatic jigging machines in the control vessels was 8-18 and the number of crews engaged for fishing operation was 3-13. Average fuel consumption of LED fishing vessels during fishing operation was 505.1l which led to an average fuel consumption of 42.7l per hour. LED fishing vessel and MH fishing vessel caught on an average 1,946 squids and 2,439 squids, respectively, during the study period. Crews (hand line and hand reel) caught about 2.2 times the automatic jigging machines for LED fishing vessel and about 2.1 times for MH fishing vessel. Meanwhile, catches by the fishing vessels with LED in the combined total number per one line of automatic jigging machine and per crew were 86.6% of that of the control fishing vessel with MH. Also, fishing vessels with LED per automatic jigging machine achieved 71.8% of catches of that with MH fishing lamp. The catches of squids per the fishing vessel with 1W LED fishing lamp were higher by more than 135.5% of that in the fishing vessel with MH, which showed a good fishing performance even with only the use of a LED fishing lamp.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.16 no.1
• /
• pp.20-26
• /
• 2002

HID(high intensity discharge)lamps include high pressure mercury lamp, high pressure sodium lamp and metal halide lamp. Metal halide lamps have been considered to be one of the most erective light sources. These lamps have good efficiency, good color rendering and good focusing capability. The objective of this research is to alum on the metal halide lamp(MH70W) by the developed electronic ballast with free voltage input(AC 100∼277V). The developed electronic ballast consists of a free voltage input converter, a flyback converter ＆ half-bridge inverter, ignitor ＆ protector and control1er. Experimental results show that developed electronic ballast turns on the metal halide lamp(MH70W) with free voltage input(AC 100∼277V) very well.

• Journal of Korean Institute of Fire Investigation
• /
• v.11 no.1
• /
• pp.31-36
• /
• 2008

This paper carried out a variety of analysis for a finding out the causes of fire on the street lamp. The glass bulb of 250W metal-halide(MH) lamps attached with the impurities rose the temperature by at $410.4^{\circ}$ in normal condition. Therefore, a lamp apparatus is needed the improvement for ventilation and the protection against dust. The heat of MH lamps is diffused through out the luminous tube, a glass bulb, and apparatus by degrees. The accident cause of the lamp is presumed that the accumulated heat by deposits of the inner part. It will be recommended the improvement of the structure that aren't the external impurity and accumulated heat in the MH lamps set.

• Journal of Electrical Engineering and Technology
• /
• v.1 no.3
• /
• pp.332-337
• /
• 2006

In this paper, an electronic ballast was developed to control a 250W metal halide lamp. To avoid acoustic resonance phenomenon, we calculated the acoustic resonance band and determined the driving frequency from 70kHz to 100kHz. Due to the switching loss of MOSFET, many problems are caused in the inverter circuit during lamp lighting, so we reduced the loss by connecting the capacitor that minimizes the magnitude of the impulsive voltage. In this paper, the main point of research is to find the methods to operate the lamp on the rated output power. After detecting the current and the voltage of the lamp, we changed the driving frequency by adjusting the DC voltage level of the VCO input.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.15 no.6
• /
• pp.8-14
• /
• 2001

MetalHalid lamps have good efficiency, good color rendition and good focusing capability. But the shortcoming of metalhalid lamps is blown as acoustic resonance phenomena in the arc tube. Such acoustic resonance produce annoying fluctuations in the intensity and distribution of the emitted light, they can raise the voltage to the point where the arc is extinguished and they can move the arc close enough to the wall to cause local overheating and tube cracking. The objective of this research is to reduce acoustic resonance in the arc tube of the Pulse Start MetaIHaide lamp(MH200[W]). To reduce the acoustic resonance phenomena the electronic ballast was designed for high frequency operation with the constant frequency sinusoidal wave of 89[kHz] in the 84.6[kHz]∼94.2[kHz] range. Experimental results show that the acoustic resonance phenomena are not in the arc tube of Pulse Start MetalHalide lamp (MH200[W]) .

• Journal of Biosystems Engineering
• /
• v.35 no.6
• /
• pp.413-419
• /
• 2010

Plant growth was greatly affected by the spectral distribution and light intensity of artificial lighting sources. In this study, the spectral characteristics of high power sodium (HPS) lamps and metal halide (MH) lamps produced by three different manufacturers were measured. Even though the spectral distribution of HPS lamps with lamp wattage of 250 W and 400 W was very similar, but the spectral light intensity by the manufacturers was different. Difference in the spectral light intensity of MH lamps by the manufacturers was increased with the increasing lamps wattage. Light intensity at the region of blue (B), green (G), red (R) and far-red (FR) light of HPS and MH lamps was also analyzed. HPS lamps showed the light intensity in order of R, FR, B and G light. The ratio of G, B, R and FR to photosynthetic photon flux (PPF) of HPS lamps with the lamp wattage of 250 W was 3.0-3.2%, 5.5-5.9%, 17.3-19.2% and 6.5-7.8%, respectively. For MH lamps, it showed the light intensity in order of R, FR, B, and G. The ratio of B, G, R, and FR to PPF of MH lamps with 250 W was 14.0-15.5%, 22.6-27.5%, 7.5-9.5% and 2.7-4.2%, respectively. HPS and MH lamps with 400 W had a relatively smaller ratio of R and FR to PPF than those with 250 W. HPS lamps showed that the ratio of light intensity of B and FR to R was 0.15-0.28 and 0.36-0.4, respectively. For MH lamps, the ratio of light intensity of B and FR to R was 1.26-2.72 and 0.27-0.56, respectively. From these results, it was concluded that the portion of blue light of MH lamps was higher than those of HPS lamps.

• Journal of Electrical Engineering and Technology
• /
• v.1 no.4
• /
• pp.496-502
• /
• 2006

In this paper, we studied the development of the electronic ballast for 250W MH (Metal-Halide) lamps. We were able to improve the input power factor by using a PFC IC. To provide the lamp with the rated voltage required, we used the buck-type dc-dc converter. The stress of the switching devices in the inverter could be reduced by this method. To eliminate the acoustic resonance phenomena of MH lamps, the voltage of the lamp added the high frequency sine-wave to the low frequency square-wave by using the full bridge typed inverter. We have developed a simple igniter using the L and C elements. We could control the dimness of the lamp by varying the output voltage of the buck converter. The buck converter output voltage could be controlled by using a microprocessor.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.58 no.10
• /
• pp.1947-1953
• /
• 2009

Metal halide (MH) lamps have been largely used due to high luminous efficiency, good color rendering, and long life. Since the metal halide lamps have problems of high ignition voltage and acoustic resonance. Thus, the design of ballast is very difficult for engineers. This paper proposes prototype of electric ballast in order to solve above two problems. The proposed electric ballast is consisted of EMI filter, full wave rectifier circuit, active PFC, DBI(Dual Buck Inverter), dimming circuit and ignitor circuit. The DBI supplies both rectangular voltage and current to the lamp. As the result of the experiment, the acoustic resonance was eliminated and the ignitor circuit was designed to generate high ignition voltage than 5kV. It makes the dimming circuit possible to control the lamp power in range between 230W and 350W.