• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.353-354
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• 2012

• Journal of the Korean Society for Precision Engineering
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• v.31 no.10
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• pp.905-911
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• 2014

A Loss-in-Weight (LIW) feeder, a type of automated measuring device, is a continuous feeder used in many mass production industries. Due to its versatility, there have been constant demands of LIW feeders in food production supply lines as well as chemical and pharmaceutical industries. In this paper, the process of designing a LIW feeder system with better performance will be examined and compared with commercial products. This system is characterized by low pass Butterworth filter and feed forward PI control. The filter is for noise disposal caused by dynamic condition of a LIW feeder. The feed forward PI control, based on linearity feature of feeders, is adequate for stable driving of the system. At the end, a possible evaluation method of LIW system will be proposed to verify the specific achievement of this paper.

• Korean Journal of Plant Tissue Culture
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• v.24 no.5
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• pp.295-303
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• 1997

To investigate the response on feeder cell cultures, protoplasts isolated from cell suspensions initiated from mature seed scutellum-derived callus of the Japonica rice variety Taipei 309, were cultured on filter membranes under various conditions. The effects of various factors, such as gelling agents, feeder cell and protoplast densities, species of feeder cells and heat shock treatment, have been investigated to improve protoplast plating efficiencies on filter membranes. Maximum protoplast plating efficiencies were obtained when protoplasts were cultured on KPR medium semi-solidified with Sea Plaque agarose at a density of $5\;\times\;10^{5}\;ml^{-1}$ protoplasts in the presence of Lolium multiflorum as feeder cells (0.5 ml pcv per 10 ml of protoplast culture medium). Pre-culture heat shock treatments for 1 min. and 5 min. to the protoplasts did not give any appreciable increase on the plating efficiency of protoplasts in the presence of feeder cells. Maltose-supplemented medium was superior for plant regeneration from protoplast-derived colonies compared with medium containing only sucrose. The plants were transferred to the glasshouse, flowered and were fertile.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.103-104
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• 2013

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.6
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• pp.1108-1114
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• 2016

The cause of failure in the AT feeding system is divided into grounding, short-circuit of feeding circuit and internal faults of the railway substation. Since the fault current is very high, real-time current is detected and the failure must be immediately removed. In this paper, a new DC offset elimination filter that can remove component to decrease in the form of exponential function using low-pass filter was proposed in order to extract the fundamental wave from distorted fault current. In order to confirm the performance of the proposed filter method, AT feeder system was modelled by simulation tool and simulations were performed under various conditions such as fault location, fault resistance and fault voltage phase angle in case of trolley-rail short-circuit fault. When applying the proposed DC-offset removal method, it can be seen that the phase delay and gain error did not appear.

• The Transactions of the Korean Institute of Power Electronics
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• v.11 no.3
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• pp.274-283
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• 2006

The Permanent Magnet Synchronous Motor(PMSM) drive systems with ball-screw, gear and timing-belt are widely used in industrial applications such as NC machine, machine tools, robots and factory automation. These systems have torsional vibration in torque transmission from servo motor to mechanical load due to the mechanical couplings. This vibration makes it difficult to achieve quick responses of speed and may result in damage to the mechanical plant. This paper presents adaptive notch filter with auto searching function of vibration frequency to reject the mechanical vibration of linear feeder system with PMSM. The proposed adaptive notch filter can suppress the torque command signal of PMSM in the resonant bandwidth for reject the mechanical torsional vibration. However, the resonant frequency can vary with conditions of mechanical load system and coupling devices, adaptive notch filter can auto search the vibration frequency and suppress the vibration signal bandwidth. Computer simulation and experimental results shows the verification of the proposed adaptive notch filter in linear feeder system with PMSM.

• Journal of the Korean Institute of Telematics and Electronics
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• v.11 no.4
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• pp.9-16
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• 1974

The low channels with frequency range of 54~88MHz and the high channels with frequency range if 174~216 MHz are in use for TV broadcasting in Korea. Since the ratio of the highest frequency to the lowest frequency is 4 to 1, only a logarithmic periodic antenna cou1d cover such an wide frequency range. But, this log-periodic antenna should be big in size. Studies have been done on an antenna of small size with reasonable gain which combines through a channel filter a LPD antenna if low channel with boom length of 2m and a LPD antenna of high channel with boom length of 1.8m. The whole antenna is connected to feeder line through a talun. Experiment shows that the gain of low and high channels is 7 dB and 9 dB respectively, which are lower than theoretical values br nomore than ldB. The difference seemed to come from slight impedance mismatches between antennas and feeder lines, loss in the filter and measurement errors.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.5
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• pp.615-625
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• 1997

An efficient protocol for plant regeneration from protoplasts of the indica rice variety IR43 has been developed. The procedure involved plating of embryogenic suspension-derived protoplasts on the surface of a filter membrane overlaying agarose-embedded feeder cells. Lolium multiflorum cell suspensions were preferable to these of Oryza ridleyi as feeder cells and Lolium suspensions supported colony formation from up to 0.68％ of the protoplasts, depending on the age of cell suspensions. Plant regeneration frequency was significantly improved by using maltose alone or in a 1:1(w/w) combination with sucrose as carbohydrate source and a simple dehydration treatment using a high concentration of agarose in the regeneration medium. Medium containing maltose or maltose mixed with sucrose increased the plant regeneration frequency compared with medium containing sucrose alone. The plant regeneration frequency was increased to 30.7 to 70.7％ following dehydration treatment, while the non-treated controls showed a regeneration frequency of 3.1 to 30.6％. Protoplast-derived plants were transferred to the glasshouse, flowered with morphologically normal.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.2
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• pp.68-71
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• 2010

This study was performed in order to obtain basic data of macrobenthic community in continental shelf exclusive economic zone (EEZ), before sand excavation. The species number of macrozoobenthos was 157, mean density was 2,529 ind./$m^2$ and mean biomass was 231.8 $g/m^2$ in November, 2000. The species number of macrozoobenthos was 179, mean density was 3,773 ind./$m^2$ and mean biomass was 391.2$g/m^2$ in February, 2001. Dominant species were Ampelisca sp. and Photis sp. in amphipods, Ophiactis branchygenys in ophiuroids and Nothria sp. and Eunice sp. in polychaetes. In the proportion of feeding types of macrobenthos, surface deposit feeders were most dominant feeding group, and followed by carnivores, subsurface deposit feeders, and filter feeders. Species diversity index (H') was high ranging from 2.5 to 3.5 at most sites.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.6
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• pp.793-804
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• 1995

Polychaetous community survey in Tomioka Bay was carried out 5 times seasonally from May 1991 to March 1992 by quantitative grab sampling (0.05m2) at 11 stations. Based on the granulometric composition and environmental factors, a homogeneous soft bottom was found in St.5-10. The species of the polychaete were classified into three feeding groups using the Fauchald and Jumars' feeding guild system. According to polychaetous community composition data, deposit feeders predominate in sandy silt area where the silt-clay content is $60-69.3\%.$ These deposit feeders were subdivided into surface deposit feeders and subsurface deposit feeders by their living position and mode. Also, suspension feeding group comes as the third dominant group. Seasonal changes of each feeding group were described in terms of numerical density and biomass. Feeding layer and types of dominant species (Lumbrineris longifolia: surface deposit feeder; Praxillella pacifica: subsurface deposit feeder; Chone duneri; suspension filter feeder, etc.) were examined in the intact sediment core samples. Also, longterm density change among the three dominant species during 10 years was disussed.