• Explosives and Blasting
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• v.28 no.1
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• pp.11-18
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• 2010

This study improved construction and cost efficiency that are disadvantages of existing low vibration crackers(low vibration cracker, plasma, etc) and introduced cases of development and practical applications of Low vibration explosives(NewFINECKER) that minimizes blast vibration. The low vibration explosives(NewFINECKER) is suitable to Type-1 among standard blasting patterns of Ministry of Land, Transport and Maritime Affairs(MLTM) and delay blasting is possible. Moreover, the low vibration explosives improve construction and work efficiency while the level of vibration is shown to be about 60~70% of normal emulsion explosives. Additionally, this study suggested standard blasting patterns, the prediction equation of blasting vibration, and construction methods.

• Proceedings of the KIPE Conference
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• 2009.11a
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• pp.246-248
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• 2009

본 논문에서는 장력 검출 장치(로드셀, 댄서 등) 가장착되어 있는 생산 설비에서 강선, 강판, 제지, 섬유, 비닐 등과 같은 소재의 장력을 정밀하게 제어하기 위한 인버터의 장력 제어 전용 PID 제어기와 직경 또는 소재의 두께를 실시간으로 추정하여 인버터의 출력 주파수를 보정하는 추정기를 제안한다. 본 논문에서 제안된 방법을 다양한 용량(0.37kW~160kW) 대의 인버터에 탑재하여 실제 부하에 적용함으로써 산업 현장에서 요구하는 수준이상의 우수한 제어 성능을 나타냄을 확인하였다.

• Korean Journal of Environmental Agriculture
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• v.34 no.4
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• pp.288-293
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• 2015

BACKGROUND: This study was conducted to investigate the effect of the unexpected early loss of leaves on a newly-bred kiwifruit on the regrowth of axillary buds the current season and the early growth and development the following year.METHODS AND RESULTS: The vines were defoliated on Jul. 18, Aug. 16, and Sep. 17 in 2012 and on Jul. 16, Aug. 13, and Sep. 12 in 2013. The vines were defoliated 0 (control), 50, and 100% of the total number of leaves on a vine. The regrowth of axillary buds at 30 days after defoliation increased in proportion to defoliation degrees regardless of the defoliated time. Defoliation the previous season did not influence percent budbreak the next season. Percentage of floral shoots of the control vines was 27.4%, each bearing 2-3 flowers. In those vines defoliated 100% in August and September, however, percent floral shoots and number of flowers significantly reduced.CONCLUSION(S): Defoliation in July, August, and September didnot affect percent budbreak the following year regardless of degrees of defoliation. A 100% defoliation in August and September significantly reduced flowering the following year compared to the control; that in August resulted in no floral buds at all.

• Journal of Bio-Environment Control
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• v.21 no.1
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• pp.74-78
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• 2012

This research was carried out to investigate the shoot growth characteristics and climatic factors for early harvest and stable yield by greenhouse on mulberry ($Morus$ $alba$) in Buan-gun, Jeollabuk-do. Budbreak and coloring date of mulberry in greenhouse were earlier 18~19 days than those in field, and from bud-break to coloring was 39 days in both cultivation types. Shoot length and fruit number per shoot of mulberry in greenhouse were not significantly different with those of field, but number of node was significantly little than that of field. For 39 days in greenhouse, weekly cumulative radiation were 0.3~0.8 times. But weekly cumulative temperature was not different with that of field. And relative humidity as range of 53.0~94.5% in greenhouse was higher than that of field. Therefore, mulberry is suitable to greenhouse cultivation for early harvest and stable yield.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.2
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• pp.99-109
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• 1994

The objective of this study was to examin some animal and sward factors which determine the daily herbage intake of high yielding dairy cows at different levels of daily herbage allowance. In this paper, the principal data relevent to the changes of sward characteristics after five days of daily strip grazing at three experimental peliods were summarized. The pregrazing herbage mass and extended height increased significantly from 5,047 kg OM/ha and 341 mm in period 1 to 6,877 kg OM/ha and 446 mm in period 3, while there was not a significant difference among herbage allowance treatments(average 6,068 kg OM/ha and 410 mm). The live leaf material in the residual herbage showed a greater reduction than the dead material and leaf sheath in terms of extended height, proportion and density. The decreased rates after grazing were higher when the level of herbage allowance decreased. Live leaves were vertically distributed to 50 cm of sward height before grazing. All live lamina distributed to 25 cm were grazed in the high and medium, and to 20 cm in the low levle of herbage allowance after grazing. The depth of grazing and grazed volume of forage material were heighly affected by the levels of hehage allowance. The biomass after grazing in the high, medium and low daily herbage allowance decreased 35, 36 and 52%, respectively, compared to before grazing level. The highly significant correlations between herbage allowance and extended tiller height(r=0.79), proportion of live lamina(r=0.94) and density of live lamina(r=O.91) after grazing, respectively, were observed.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.273-279
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• 2009

This study was conducted to identify optimal concentrations of N (nitrogen) and K (Potassium) fertilizers on growth, yield and quality of melon (Cucumis melo. L) when they were grown with a fertigation culture in a greenhouse. Three strength (S) levels of fertilizers, including 1 S, 1/2S, and 1/4S were supplied N and K nutrients as using a trickle irrigation system. When the strength level of fertilizers was increased from 1/4S to 1 S, the level of EC (electronic conductivity) in soil was increased. Soil-water tension was ranged between -15 and -20kPa until fruit setting stage, whereas it was ranged between -45 and -50kPa in the later growth stages. In results, N fertilizer had effects on fruit yield and quality. A higher fruit yield was observed when plants were supplied with 1 S and 1/2S level of N fertilizer. The highest yield of marketable fruit, about 5,086kg/10a, was also observed when plants were supplied with 1/2S N fertilizer. A higher net index and sugar content of fruit was observed in the treatments of 1/2S and 1/4S level of N fertilizer compared to 1 S level. In contrast, there was no statistic difference in the yield and quality with three levels of K fertilizer. Results indicate that the 1/2S level for N and 1/4S level for K fertilizer are effective and optimal for the melon plants grown under the fertigation culture in terms of increasing fruit yield and quality and reducing the cost of fertilizers.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.2
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• pp.110-119
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• 1994

Measurements of hehage intake and milk yield were made on high yielding dairy cows, which were strip-grazed on Loliurn perenne sward at three levels of herbage allowance in three experimental periods. The contents of nitrogen, chrome and ash in the faeces slightly decreased with the progress of growth period of experimental sward, and the decrease of herbage allowance. There were small difference in herbage digestibility among periods or the levels of herbage allowance with falling from 82.7% to 79.1% from period 1 to period 3 and from 81.6% to79.9% from high to low level of herbage allowance. Daily herbage intake was 15.8 and 15.9 kg OMIcow at the high and medium levels of hecbage aljowance, but reduced significantly to 14.6 kg OM/cow at the low level. Herbage intakes in three periods were shown a slight decrease. Daily milk yield in terms of 4% FCM significantly decreased from 23.6 to 20.6 kg/cow from period 1 to period 3. Milk yield at the high and medium levels of herbage allowance were 23.5 and 22.2 kg/cow at the low level of herbage allowance. The highly significant (P<0.01) correlations between the level of herbage allowance and herbage intake (r=0.88), or milk yield (r=0.81) were obtained.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.3
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• pp.179-183
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• 1990

In order to find out the effects of nitrogen fertilizer, planting density and seeding date of Okra (Abelmoschus esculentus (L) MOENCH), three nitrogen fertilizer level (4, 8 and 10kg N/10a), three planting densities (45${\times}$30cm, 60${\times}$30cm and 90${\times}$30cm) and five seeding date (April 15, May 1, May 15, June 1 and June 15) were treated. Treatment of 8kg N/10a among nitrogen fertilizer level and 45${\times}$30cm among planting densities showed higher green and yield than the other treatments. The plot of 45${\times}$30cm with 8kg N/10a showed the highest yield. Among planting date, May 1 planting date obtained the highest yield.

• Korean Journal of Poultry Science
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• v.6 no.1
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• pp.12-23
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• 1979

This experiment was carrid out to investigate the interaction between boilelr strains and nutrition levels, and the performances of four broiler strains such as Han Hyup 603, Hubbard, Anak and Filch when they were fed by four different nutrition levels (High Protein and energy; HP. HE., Medium Protein and energy; MP. ME., Low Protein ana energy; LP. LE., and low protein and energy; LLP. LLE.). The data used in this study were obtained from a total of 1200 broiler type chicks in Poultry Testing Station, Korean Poultry Association from June 16, to August 11, 1978. Differences of all characters among four nutrition levels were significant except viability and carcass rate. HP. HE and MP. ME treatments showed nearly the same performances in body weight, feed efficiency and point, spread but they were significantly superior to those of LP. LE and LLP. LLE. There were not significant differences among four strains in feed efficiency and viability but other characters, body weight, point spread and carcass rate were observed that the performance of the best strain B was significantly superior to strain D but it was not recognized significance compared with strain A, C in tile result of statisticel analysis. In the interaction between strains and nutrition levels, body weight at high and levels showed significantly differences but at low and low nutrition levels were nearly same among four strains. Therefore this study demonstrated that comparision of body weights between strains should be performed at medium nutrition level or above. Also point spread calculated as index of body weight and feed efficiency was observed that strain B at low nutrition level is excellently higher than other strains and there were little differences at low nutrition level among all strains. It was found that ]it tie differences between performances of high arid medium levels seemed to be as the reason of high fat addition for energy source to high mutrition feed, and in general superior strain showed good performance at all the nutrition levels in$.$all characters but in body weight and point spread there were significantly different responses with different nutrition level, The most superior strain B among four strains earned the most profit per bird, Although performances of high and medium nutrition levels were nearly the same, medium nutrition level also showed the most profit because the feed cost of high nutrition level was higher than that of medium nutrition level.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.11
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• pp.1011-1016
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• 2010

The $H_2S$ adsorption characteristics and property analyses of granular activated carbon adsorbent impregnated with basic solution such as NaOH, KOH, and $(CH_2CH_2OH)_2NH$ were investigated. The concentrations of NaOH and KOH reagent ranged over 1 to 5 M, The concentration of $(CH_2CH_2OH)_2NH$ was in the range of 0.1 to 1 M. Adsorption temperature($25{\sim}45^{\circ}C$) and adsorbate ($H_2S$) concentration (18.23 mg/L) were applied. The experimental results showed that the BET surface area of activated carbon impregnated with KOH decreases from $1,050\;m^2/g$ to $750\;m^2/g$, and the acidity of activated carbon impregnated with NaOH decreases from 0.541 meq/g-AC to 0 meq/g-AC, as the concentration of basic solution increases, while the pH of impregnated activated carbon increased from 9.54 to 10.94 for three basic solutions. It was also found that the $H_2S$ adsorption equilibrium capacity of activated carbon impregnated with NaOH, KOH, $(CH_2CH_2OH)_2NH$ increased with increasing temperature and $H_2S$ adsorption equilibrium capacity of the activated carbon impregnated with diethanolamine was much higher than other cases. At adsorption temperature of $45^{\circ}C$, the $H_2S$ adsorption equilibrium capacity of impregnated activated carbon was 2.0~3.3 times lager than that of pure activated carbon.