• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.192-197
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• 1989

Two sweet corn hybrids, 'Tanok l' and 'Golden Cross Bantam 70 (GCB 70)' were grown at five plant densities, of 4, 167. 5,556, 6,667. 8, 333, and 11, 111 plants per 10 ares, with or without tiller removal, to determine effects of tiller removal on growth and yield of sweet corn hybrids at various plant densities. Tillers were pulled when less than 15 cm tall. The number of tillers per plant linearly decreased as plant density increased. The two hybrids had similar plant height, ear length and diameter, ear weight and the number of ears per plant and 10 ares. Tanok 1 lodged approximately 20％ at above 8,333 plants per 10 ares, while GCB 70 did not lodge at all, at any plant density. Tanok 1 had higher leaf area index (LAI), ear and stover yields than GCB 70. Except for root lodging and LAI, hybrid x plant density interaction was not significant at 5％ probability level. Plant density did not affect silking data. Increasing plant density linearly increased plant height, LAI, and stover yield, but linearly decreased ear length, ear weight, and the number of ears per plant. Increase in LAI was greater in Tanok 1 than in GCB 70, with increasing plant density. The relationships between the number of ears and ear yield per 10 ares and plant density were Quadratic. The optimum plant density was estimated to be approximately 6500 plants per 10 ares, using the equation based on ear yield. Except for ear height and LA I, hybrid x tiller removal and plant density x tiller removal interactions were not significant. Hybrid x plant density x tiller removal interaction was not significant for any characters. When averaged over hybrids and plant densities, tiller removal reduced plant height and ear and stover yields by about 3, 10, and 16％, respectively, but did not significantly affect silking date, root lodging, ear length and diameter and the number of ears per plant and per 10 ares. The results indicate that the optimum plant density is approximately 6500 plants per 10 ares, regardless of tiller removal and tillers are not to be removed at any plant density.

• Korean Journal of Plant Tissue Culture
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• v.25 no.1
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• pp.27-31
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• 1998

Immature hybrid embryos of H. hybridum, 'Picottee', 'White Christmas', 'Eldorado', 'Origin', 'Red Lion', 'elstar', 'Crypsy' were cultured on the MS medium supplemented with various concentrations of 2,4-D, NAA, BA and TDZ. Among the treatments, NAA were more effective for the shoot regeneration and bulblet formation than other treatment. Addition of 0.5 ㎎/L NAA was effective for bulblet induction from explant Shoot regeneration was most effective on the medium with 1.0㎎/L NAA and 2.0 ㎎/L TDZ. The addition of 1.0-2.0㎎/L TDZ induced numerous shoots per explant but strongly inhibited root development when compared to 1.0-2.0㎎/L BA. When bulb scale segments of 'Star Van Holland' was incubated, bulblet formation was the most effective on MS medium with 0.5㎎/L NAA.

• Journal of Aquaculture
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• v.13 no.4
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• pp.353-357
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• 2000

Porphyra pseudolinearis and P. dentata from Korea were crossed and the hybrid was cultured at different temperatures (5, 10, 15, 20 or $25^{\circ}C$), photon flux densities (10, 20, 40 or 80${\mu}$mol m$^{-2}$s$^{-1}$) under photoperiods (14L:10D and 10L:14D). In the hybrids, the conchocelis grew faster at 2$0^{\circ}C$ and 40$\mu$mol m$^{-2}$ s$^{-1}$ at $25^{\circ}C$ only, and were abundant, when cultured under 10L:14D. Foliose thalli of the hybrid grew rapidly at conditions of 10-2$0^{\circ}C$, 10L:14D and 15-2$0^{\circ}C$, 14L:10D but slowly at 5 and 2$0^{\circ}C$. No archeospores were observed any tested culture condition. Spermatangial and zygotosporangial sori were formed at the marginal portion o mature thallus. Zygotospores from the hybrid were released at 10-2$0^{\circ}C$ under both photoperiods, and gave rise to form conchocelis filament. Monoecious thalli were observed at 1$0^{\circ}C$ under 14L:10D. Neither monospores nor protothalli were produced from the conchocelis in culture.

• Journal of Life Science
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• v.6 no.4
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• pp.219-226
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• 1996

The fruit yield and morpholgical characters of F$_{1}$ hybrids between Capscium annuum L. 'California Wonder', four native Japanese cultivars, and three Korean F$_{1}$ cultuvars were evaluated and the results compared with parental cultivars. The F$_{1}$ hybrids obtained by crossing 'California Wonder' and native Japanese cultivars flowered 3 days earlier on average compared to parental cultivars. The yields of F$_{1}$ hydrids were higher than those of the parental cultivars, especially when one of the parents was 'California Wonder'. Also F$_{1}$ hybrid whose one parent was 'California Wonder' and 'Fushimi Amanaga' gave the highest fruit yield. The number of locules and seeds per fruit from of the 'California Wonder' hybrids whose one parent was 'California Wonder' was more than of the native Japanese cultivars. The plant height in F$_{1}$ hybrids obtained by crossing between 'California Wonder' and four native Japanese cultivars tended to be higher than that of the parental cultivars.

• Proceedings of the Korean Society of Tobacco Science Conference
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• 2001.05a
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• pp.35-43
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• 2001

일대잡종육종이란 현대의 다양한 육종기술 중 하나로 교배 제1세대의 잡종강세현상을 곧바로 이용하는 것으로 여러 작물에서 실용적으로 이용되고 있다. F$_1$잡종종자를 생산하려면 자가수분을 통제해야 하는데 웅성불임을 이용하면 자친의 화분제거 노력이 생력되어 경제적인 종자생산이 가능하다. 연초는 자식성 작물로 잡종강세는 높지 않으나 종간 교잡에 의한 cms가 만들어진 이후 버어리종 등에서는 60년대부터 직적형질에 가깝게 유전되는 우성 단일유전자의 지배를 받는 N. logniflora의 역병(race 0)저항성을 도입한 웅성불임(cms) F$_1$잡종이 활발하게 이용되어 왔다. 최근에는 cms F$_1$잡종의 이용영역이 넓어져 우리나라의 경우 N. glutinosa에서 유래한 우성 단일인자 TMV저항성을 도입한 황색종 cms F$_1$잡종 KF 114가 주 재배품종이 되었고 버어리종에서는 VAM에서 유래한 열성단일유전자의 지배를 받는 PVY저항성이 도입된 KB 111의 확대재배가 예상되고 있다. 본 글에서는 cms F$_1$잡종의 국내외 이용 사례를 살펴보고 cms F$_1$잡종의 육성과 이용방향, cms F$_1$잡종 종자생산에 관하여 기술하였다. 그리고 병저항성뿐 아니라 알칼로이드함량, 염록소함량, DVT나 챤-abienol 및 SE함량 등 질적형질에 가깝게 유전되고 유전양식이 명확하게 밝혀진 화학성분에 대해서도 F$_1$잡종 육성의 대상 형질로 논의하였다.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.525-528
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• 2008

A new graft cactus (Copiapoa scopa) cultivar 'Redstone' was developed at Cactus Research Institute, Gyeonggi-do A.R.E.S, in 2007. GCP563 and GCP618 were crossed in 2004 and we got 9 seedlings from this combination. After pedigree selection in 2005, one cultivar was finally selected through the test of specific character in 2007 and named as "Redstone". "Redstone" cultivar has red brown color and round globose shape with 15 ribs and its spines are black. This cultivar is able to produce 26.8 offshoots per plant. 'Redstone' cultivar has higher productivity and more slow growth than Copiapoa scopa cultivar.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2000.09a
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• pp.201-210
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• 2000

Rock bridge in rock masses can be considered as one of several types of opening-mode fractures, and also it has been known to have a great influence on the stability of structures in rock mats. In the beginning of researching a rock bridge it used to be studied only in characteristics of its behavior, as considering resistance of material itself. However the distribution pattern of rock bridges, which can affect the stability of rock structures, is currently researched with a fracture mechanical approach in numerical studies. For investigating the effect of rock bridges on the development pattern of hydraulic fractures, the author analyzed numerically the stress state transition in rock bridges and their phenomena with a different pattern of the rock bridge distributons. From the numerical studies, a two-crack configuration could be defined to be representative of the most critical conditions for rock bridges, only when cracks are systematic and same in their length and angle. Moreover, coalescence stresses and onset of propagation stresses could be known to increase with decreasing s/L ratio or increasing d/L ratio. The effect of pre-existing crack on hydraulic fracturing was studied also in numerical models. Different to the simple hydraulic fracturing modeling in which the fractures propagated exactly parallel to the maximum remote stress, the hydraulic fractures with pre-existing cracks dial not propagate parallel to the maximum remote stress direction. These are representative of the tendency to change the hydraulic fractures direction because of the existence of pre-existing crack. Therefore s/L, d/L ratios will be identical as a function effective on hydraulic fractures propagation, that is, the $K_{I}$ vague increase with decreasing s/L ratio or increasing d/L ratio and its magnification from onset to propagation increases with decreasing s/L ratio. The scanline is a commonly used method to estimate the fracture distribution on outcrops. The data obtained from the scanline method can be applied to the evaluation of stress field in rock mass.s.

• Tunnel and Underground Space
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• v.10 no.3
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• pp.447-456
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• 2000

Rock bridge in rock masses can be considered as one of several types of opening-mode fractures, and also it has been known to have a great influence on the stability of structures in rock mass. In the beginning of researching a rock bridge it used to be studied only in characteristics of its behavior, as considering resistance of material itself. However the distribution pattern of rock bridges, which can affect the stability of rock structures, is currently researched with a fracture mechanical approach in numerical studies. For investigating the effect of rock bridges on the development pattern of hydraulic fractures, the author analyzed numerically the stress state transition in rock bridges and their phenomena with a different pattern of the rock bridge distributions. From the numerical studies, a two-crack configuration could be defined to be representative of the most critical conditions for rock bridges, only when cracks are systematic and same in their length and angle. Moreover, coalescence stresses and onset of propagation stresses could be known to increase with decreasing s/L ratio or increasing d/L ratio. The effect of pre-existing crack on hydraulic fracturing was studied also in numerical models. Different to the simple hydraulic fracturing modeling in which the fractures propagated exactly parallel to the maximum remote stress, the hydraulic fractures with pre-existing cracks did not propagate parallel to the maximum remote stress direction. These are representative of the tendency to change the hydraulic fractures direction because of the existence of pre-existing crack. Therefore s/L, d/L ratios will be identical as a function effective on hydraulic fractures propagation, that is, the K$_1$ value increase with decreasing s/L ratio or increasing d/L ratio and its magnification from onset to propagation increases with decreasing s/L ratio. The scanline is a commonly used method to estimate the fracture distribution on outcrops. The data obtained from the scanline method can be applied to the evaluation of stress field in rock mass.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.53-68
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• 1998

Observation of hydrometeors' behavior in the atmosphere is important to understand weather and climate. By conventional observations, we can get the distribution of water vapor at limited number of points on the earth. In this study, the precipitable water has been estimated from the split window channel data on GMS-5 based upon the technique developed by Chesters et al.(1983). To retrieve the precipitable water, water vapor absorption parameter depending on filter function of sensor has been derived using the regression analysis between the split window channel data and the radiosonde data observed at Osan, Pohang, Kwangiu and Cheju staions for 4 months. The air temperature of 700 hPa from the Global Spectral Model of Korea Meteorological Administration (GSM/KMA) has been used as mean air temperature for single layer radiation model. The retrieved precipitable water for the period from August 1996 through December 1996 are compared to radiosonde data. It is shown that the root mean square differences between radiosonde observations and the GMS-5 retrievals range from 0.65 g/$cm^2$ to 1.09 g/$cm^2$ with correlation coefficient of 0.46 on hourly basis. The monthly distribution of precipitable water from GMS-5 shows almost good representation in large scale. Precipitable water is produced 4 times a day at Korea Meteorological Administration in the form of grid point data with 0.5 degree lat./lon. resolution. The data can be used in the objective analysis for numerical weather prediction and to increase the accuracy of humidity analysis especially under clear sky condition. And also, the data is a useful complement to existing data set for climatological research. But it is necessary to get higher correlation between radiosonde observations and the GMS-5 retrievals for operational applications.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.152-160
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• 2005

This study was carried out to investigate selectable criteria in evaluating waxy corn $F_1$ hybrids for developing good eating quality waxy corn variety. The physicochemical property analysis of 6 waxy corn $F_1$ hybrids - Chalok1, Chalok2, Heugjeomchal, Yeonnongl, Chalok4, and Suwon45- showed a range of $11.2\~13.1\%$ for crude protein, $5.1\~6.0\%$ for crude fat, $91.8\~92.6\%$ for amylopectin, and $4.5\~6.6\%$ for free sugar content. The pericarp thickness which is one of the most important characteristics related to tenderness in waxy corn was ranged $34\~47{\mu}m$ in 4 waxy corn hybrids - Yeonnongl, Chalok4, Suwon45, and Heugjeomchal. On the other hand, it was ranged $64\~81{\mu}m$ in Chalok1 and Chalok2. The amylogram analysis by rapid visco analyzer showed that in fresh waxy corn hybrid (DAP25), all amylogram properties except setback were higher in Yeonnongl, Chalok4, and Suwon45 compared to those of Chalokl, Chnlok2, and Heugjeomchal. However, in matured waxy corn hybyids (DAP45), the result was the opposite - the amylogram properties were higher in Chalokl, Chalok2, and Heugjeomchal than those of Yeonnongl, Chalok4, and Suwon45. The texture analysis showed that gumminess, chewiness, and hardness increased dramatically with the time after the cooking in Chalokl and Beugjeomchal. On the other hand, these above pyoperties did not change as rapidly with the time in Yeonnongl, Chalok4, and Suwon45. Gumminess, chewiness, and hardness did not increase much within 6 hours after steamingr but increased significantly 32 hours after steaming. Therefore, we have reached a conclusion that texture analysis of cooked waxy corn should be carried out 6 hours after steaming. In the sensory evaluation, Yeonnongl, Chalok4, and Suwon45 revealed higher palatability -6.8, 7.1, and 6.9 respectively - than. that of Chnlokl, Chalok2, and Heugjeomchal. The palatability analysis of 6 waxy corn hybrids showed palatability positively correlating with free sugar content,100-kernel weight, kernel length, kernet width, and consistency, but negatively correlating with pericarp thickness, hardness, gumminess, and chewiness.