• The Journal of Engineering Geology
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• v.17 no.2 s.52
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• pp.309-315
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• 2007

The purpose of this paper is to make a close inquiry into the relationship between width and length of crack as a method to maximize compensation effect by grouting discontinuity within weak bedrock, together with emphasis on application of the basic data to the reformation of weak bedrock in a construction site. The result reveals that the length of trace at each fracture averages $1.5{\sim}3.0mm$. Based on analysis of openness distribution pattern at each fracture, the estimated values are quite well in agreement with those of the experiment, with a negative trend in the distribution of aperture width.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.6
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• pp.485-491
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• 2004

Spawning induction, egg development and larval growth of ark shell (Tegillarca granosa) (L.) were investigated. The most effective method of spawning induction was steady temperature increasing from$4^{\circ}C\;to\;28^{\circ}C$ with irradiation of sea water by UV after T. granosa was exposed to air at $4^{\circ}C$ Optimum condition for larval roaring was under the 32.4 psu and two temperature $regimes:\;28{\pm}1^{\circ}C\;and \;25{\pm}1^{\circ}C$. Fertilized eggs was demersal isolated eggs, and egg diameter was $60{\mu}$. D-shaped larvae appear about 20 hr after hatching with $94.1{\mu}$ in shell length and $86.7{\mu}$ in shell height. Ten days were required from hatching to umbo larva stage, of a mean shell length $125.2{\mu}$. On 25th day, the larva grew to $450{\mu}$ in shell length and began to settle on the bottom. Effect of temperature between $25^{\circ}C$ (control group) and $28^{\circ}C$ on larval growth was not different. Survival rate of larvae settled on the bottom was about $19{\%}$ in both temperatures conditions $(25^{\circ}C\;and\;28^{\circ}C)$.

• Textile Coloration and Finishing
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• v.27 no.3
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• pp.165-174
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• 2015

To develop automobile parts, the unsaturated polyester based matrix resin(PR)/reinforcement(randomly oriented chopped E-glass fiber, GF) composites were prepared using sheet molding compound(SMC) compression molding. The effects of GF length(0.5, 1.0 1.5 and 2.0inch)/content (15, 20, 25, 30wt%) and number of ply(3, 4 and 5) on the specific gravity and mechanical properties of PR/GF composites were investigated in this study. The optimum length of GF was found to be about 1.0inch for achieving improved mechanical properties(tensile strength and initial modulus). The tensile strength and initial modulus of composites increased with increasing GF content up to 30wt%, which is favorable content range for SMC. The specific gravity, tensile strength/initial modulus, compressive strength/modulus, flexural strength/modulus and shear strength increased with increasing the number of ply up to 5, which is the maximum number of ply range for SMC. The effectiveness of ply number increased in the flexural strength > shear strength > compressive strength > tensile strength.

• Culinary science and hospitality research
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• v.23 no.4
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• pp.185-192
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• 2017

This study examined the optimum conditions and obtained the basic data for processing semi-dried sea cucumber flakes. During the boiling process, the weight and length of the sea cucumber decreased to 45.61% and 55.87%, respectively. Thereafter, there was a gradual decrease in the weight and length of the sea cucumber, which were finally maintained at 30.00% and 50.93%, respectively. The moisture content during drying was 38.37% after 3 hours at $60^{\circ}C$, and 36.56% after 5 hours at $30^{\circ}C$. However, the decrease in moisture content was slowly at 60 hours and $4^{\circ}C$, reaching a final value of 68.9%. The length of boiled sea cucumber during drying decreased to 66.35% after 11 hours at $60^{\circ}C$, and 68.90% after 24 hours at $30^{\circ}C$. The chromaticity and hardness tended to increase during the drying process. Moisture content and water activity of sea cucumber flakes decreased from 81.48% (0.963) to 33.50% (0.763), respectively, after 3 hours at $60^{\circ}C$. Following this, the moisture content and water activity continuously decreased to 30.75% (0.608) at 4 hours and 19.47% (0.437) at 5 hours, respectively. The overall acceptance score was 4.11 and 3.89 for 4 hours dry sample and 5 hours dry sample, respectively. However, the score was not statistically significant.

• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.411-417
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• 2006

This experiment was conducted to study whether priming with deep sea water results in enhancement of seed germination and to identify the optimum concentration of the priming solution, and duration of priming using sweet pepper (Cv. California wonder), rice (Cv. Ilpum) and ginseng seed. Sweet pepper and rice seeds were primed with 5 various concentrations (5%, 10%, 15%, 20% and 30%) for deep sea water for 48 hours, 24 hours and 12 hours at $25^{\circ}C$ and ginseng seeds in 5%, 10%, 15%, 20%, 25% and 30%, and 2,4,6, and 8 electrical conductivity (EC) which were made by desalinating deep sea water. Priming in deep sea water (DSW) improved the early and final germination percentage, mean germinal on rate, emergence percentage and root and shoot length, compared with plain water, $KNO_3$ and without priming treatments. In sweet pepper, 24 hours priming with 5 percentage DSW significantly improved the early germination percentage and radical length. It has also improved the mean germination and emergence days and early emergence percentage, compared with $KNO_3$ and control. Whereas, in rice, 48 hours priming with 10 percent DSW significantly improved the early germination percentage, plumule emergence percentage, root length and shoot height. Hence the best seed priming treatment on sweet pepper and Rice are 24 hours with 5 percentage DSW and 48 hours with 10 percentage DSW, respectively, whereas in ginseng, priming with EC4, EC8 and 25% DSW had shown better germination.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.5
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• pp.315-322
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• 2007

Kjellmaniella crassifalia Miyabe is one of the valuable seaweed crops cultured in the Korean coastal waters of the East Sea. Unfortunately recent environmental changes have adversely influenced its growth, prompting the need to develop techniques for species restoration. To obtatin biological information, the growth of the species was monitored for one year. The maximum blade length, $110{\pm}45cm$, was attained in July, and zoospores were released in November. The optimum culture conditions allowing juvenile sporophytes to grow to young blades consisted of $20{\mu}mol/m^2s\;at\;10^{\circ}C$ under which the blade length grew to $1,732.5{\pm}143.3{\mu}m$ in 42 days. Sporangial sori started to form in September, reaching 85% maturity in November and 89% maturity in December. Examining the growth of the species according to depth, the individuals growing at 5 meters grew the most, reaching a blade length of $75.9{\pm}18.9cm$ in August.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.10b
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• pp.53-59
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• 2000

This study was carried out to determine the effect of sowing time on the flowering, growth and yield of Schizonepeta tenutfozia Briquet. Emergence and flowering dates in the sowing time from March 30 to April 30 were earlier than those of the other sowing times. In the sowing time from March 30 to April 30, length and diameter of main stem, number of node per main stem, number of branch per plant and fresh and dry weight of stem were greater than those of the other sowing times. Yield components such as ear length, main stem length and diameter, branches per plant, number of node and ears per plant, yield of stem in fresh and dry were the highest at the sowing time from March 30 to April 30. Optimum sowing time of Schizonepeta tenuifolia Briquet were from March 30 to April 30 in southern areas of Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.3
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• pp.193-200
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• 1992

This study was carried out to determine the optimum fertilizer level of phosphate for maximum yield of soiling cowpea(Vigna sinensis Endlicher) in Cheju. The results obtained are summarized as follows:1. Plant length, fresh yield, stem and leaf weight per plant, node number of main stem, primary branch number per plant, pod number per plant and pod weight per plant increased with increasing of phosphate level regardless of growth stage.2. Plant length and node number of main stem did not increase after August 25, 40 days after planting. Leaf weight and fresh yield were greatest on August 25, and then reduced. 3. Stem weight the number of leaves and pods and pod weight per plant increased until September 13, 80 days after planting. 4. Increased level of phosphate delayed leaf weight decrease after August 25. 5. Root length and root weight per plant increased with increasing level of phosphate regardless of growth stage, and they did not increase after Augest 25. 6. Nodule number and nodule weight per plant also increased as phosphate rate increased regardlessof growth stage. Nodule number and nodule weight were greatest on August 5, and then rapidly decreased.

• Journal of Sensor Science and Technology
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• v.19 no.6
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• pp.449-455
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• 2010

Implantable middle ear hearing devices(IMEHDs) have being actively studied to overcome the problems of conventional hearing aids. Vibration transducer, an output devices of IMEHDs, is attached on the ossicular chain and transmits mechanical vibration to cochlea. This approach allows us to hear more clear sound because mechanical vibration is effective to transfer high frequency acoustics, but occurs some problems such as fatigue accumulation to ossicular chian and reduction of vibration displacement caused by mass loading effect. Recently, many studies for the round window stimulation are announced, because it does not cause such problems. It have been studied by older transducers designed for attaching on ossicular chain. In this paper, we proposed a new electromagnetic transducer which consists of two magnets, three coils and a vibration membrane. The magnet assembly, magnet coupled in opposite direction, were placed in the center of three coils, and the optimum length of each coil generating maximum vibrational force was calculated by finite element analysis(FEA). The transducer was implemented as the calculated length of each coil, and measured vibration displacement. From the results, it is verified the vibration displacement can be improved by optimizing the length of coils.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.241-245
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• 2006

EEFL(External Electrode Fluorescent Lamp) for LCD displays are analyzed on electrical and optical characteristics by various electrode length. The electrodes of EEFL are coated at the outside of the glass tube. Brightness and efficiency of the EEFL are affected on lamp impedance characteristic. So, the experimental models are proposed for analysis and measurements of the brightness and efficiency of the lamps according to the electrode length. The sample of LCD backlight unit is used for these experiments, EEFL arrayed BLU of 32' for commercial TV display. The parameters of the experiments were quantised for simple result reading as the length of electrodes as 15, 23 and 30 mm. The inverter was designed and manufactured in the laboratory as the Full-Bridge switching inverter. The feature of the output were measured on voltages about 1000 - 1400V at the currents of 11 - 29 mA and the brightness $15,000\;cd/m^2-40,000\;cd/m^2$. The experiments have shown that the brightness are increased by increasing of the electrode lengths which have the lamp currents increased. But at an certain conditions, the brightness and efficiency were decreased because of unmatched between the inverter output and lamp impedance. The optimum applications of the EEFL BLU of 32' in this experiments have been shown to choose the parameters for driving frequencies of 100 kHz - 150 kHz, the brightness of $18,000-19,000\;cd/m^2$ and efficiencies of 40 - 45 lm/w.