• Journal of Fisheries and Marine Sciences Education
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• v.19 no.3
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• pp.478-490
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• 2007

A technology of ultrasonic biotelemetry for tracking fish behavior is investigated. The ultrasonic biotelemetry system is constituted by a transmitter and a receiving system. Because a pinger was mainly used for the transmitter, the capability for pinger to possess was investigated and the efficient usage for pinger was examined. A source pressure level and a frequency were synthetically examined so that pinger could realize small size, a light weight, and a long life time. The receiving system is divided roughly into directional hydrophone systems and acoustic positioning systems by the receiving method. The directional hydrophone system is divided into single beam and multiple beam with the number of hydrophone, and the acoustic positioning systems is divided into LBL (Long Base Line), SBL (Short Base Line), and SSBL (Super Short Base Line) on the basis of base line. The present situation, the merits and demerits, and the principle of each receiving method were investigated in detail, and the efficient usage for each receiving method were examined.

• Journal of Power Electronics
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• v.3 no.1
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• pp.10-16
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• 2003

Implementation and experimental verification of a simple neuro-controller (SNC) as a speed controller for a brush less DC (BLDC) motor is presented. The SNC with one weight and a linear hard limit activation function is trained on-line using the back propagation algorithm. A modified error function is used to ensure good performance during the on-line training, which has been used without previous off-line training. The SNC has been implemented using a computer-interface card mounted on a PC. The driving system performance has been investigated by a number of experimental tests for a variety of input reference speed trajectories.

• Proceedings of the Korea Concrete Institute Conference
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• 1990.10a
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• pp.95-100
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• 1990

The behavior of short span filled spandrel arch bridge of 10 and 21 m span with various axis line, rise and backill height were investigated under the design loads(self weight, earth pressure, temperature load, live load, etc). Even though the behaviors of arch were known as relatively complicated, the followings can be concluded within the limits of this study. The design value of arch bridge increase as the rise decreases, the effects of temperature load become dominant for the design of arch bridge, and governing design factors are occured at springing.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.6
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• pp.1071-1077
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• 2009

Because several winds cause the a fault of transmission supply, KEPCO trys to protect the the trouble and supply the power stably. Kepco find out the weak mountains by winds and strengthen the power equipment annually. Power quality is the competition power in the international world and satisfy the customer using th power Therefore this paper deals with the fault relation between winds and transmission line.

• Journal of Electrical Engineering and Technology
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• v.7 no.1
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• pp.23-33
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• 2012

The current paper deals with a new live-line insulator inspection tool system that will be used by the Korea Electric Power Corporation for its 154 kV power transmission lines in 2011. Unlike the existing contact type tools, the developed inspection tool automates parts of the insulator inspection process using a sensor and an actuator. The tool sustains its weight independently, not by a lineman. In addition, the inspection tool measures the insulation resistance of an insulator together with its distribution voltage, thus providing more information for analysis and diagnosis. Such characteristics improve the system's operation efficiency, measurement reliability, and usability. We confirmed its effectiveness through live-line field tests with actual power transmission lines.

• Proceedings of the IEEK Conference
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• 2000.06c
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• pp.13-16
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• 2000

In this paper, we propose hybrid control method of neural network using the 3-point search algorithm. Proposed control method is searched the weight using the 3-point search algorithm for off-line then control the on-line. In order to verify the usefulness of the proposed method, we simulated the proposed control method with one link manipulator system and confirmed the excellency.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.5
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• pp.400-404
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• 2004

Growth performances of the selected and the non-selected red sea bream (Pagrus major) lines were evaluated up to marketable size. The offspring were mass-produced either from the selected line (the fourth generation of broods from mass selection) or the non-selected line (the second generation of wild broods). Early (59 to 103 days old, trial I) and late growth performances (4 to 24 months old, trial II) were evaluated based on communal rearing in land-based tanks and sea cages, respectively. In trial I, the selected line exhibited significantly higher values in both weight gain (WG) and specific growth rate (SGR) when compared to those observed in the non-selected line (P<0.05). In trial II comprising of three growth phases (4-9, 9-16 and 16-24 months old), selected line showed only slightly improved in WG and SGR at the beginning two growth phases (4-9 and 9-16 months old) (P>0.05), however, displayed significantly higher values at the last growth phase (16-24 months old) (P<0.05). Overall WG and SGR throughout the experiment (4-24 months) were also significantly higher in the selected line than the non-selected line (P<0.05). Consequently, mean body weight of the selected line at 24 months old was 1.4-fold (40.8{\%}\;increased) as compared to that of the non-selected line. This present result indicates that mass selection of this species against the growth traits might be quite effective, and the present advance has important Implication in the productivity enhancement of red sea bream aquaculture.

• Journal of the Chungcheong Mathematical Society
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• v.33 no.4
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• pp.497-504
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• 2020

A weight ω on the positive half real line [0, ∞) is a positive continuous function such that ω(s + t) ≤ ω(s)ω(t), for all s, t ∈ [0, ∞), and ω(0) = 1. The weighted convolution Banach algebra L1(ω) is the algebra of all equivalence classes of Lebesgue measurable functions f such that ‖f‖ = ∫0∞|f(t)|ω(t)dt < ∞, under pointwise addition, scalar multiplication of functions, and the convolution product (f ⁎ g)(t) = ∫0t f(t - s)g(s)ds. We give a sufficient condition on a weight function ω(t) in order that L1(ω) has a bounded approximate identity.

• Korean Journal of Computational Design and Engineering
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• v.10 no.1
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• pp.17-26
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• 2005

In-line skate generally consists of four major parts: boot, frame, bearing and wheel, and the most important part among those for necessary functionality is the frame. It is the most expensive, and it also makes a decisive role in practical race skating. The functional behavior of a frame is greatly affected by external dynamic forces as well as the static weight of a skater. We are proposing a new inline speed-skating frame design that has been improved in structural strength and weight for providing optimum speed in $20\sim40km$ marathon skating.

• Journal of the Korean Society for Railway
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• v.11 no.5
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• pp.499-503
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• 2008

The catenary line and feeder line installed on same electrical pole in opened place of AC electrical rail-road. The Electrical pole has receive a different weight from the catenary line and feeder line. So we have designed the Feeder supporting metal with new shape and material based on this fact. And then we have examined the stability of Feeder supporting metal designed a steel pipe by FEM program. New steel pipe compared with existing steel pipe on a economy respect. That result give proof the stability and economy as feeder supporting steel. There-fore this device have a basic of Value Engineering, so we have the need of reflection to design as a device of new electrical pole.