• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.2
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• pp.198-203
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• 2007

This study was carried out to obtain basic informations for gene action of quantitative characters including shattering resistance. The parental varieties used for $5{\times}5$ half diallel crosses were 'Yangbaek' and 'Ansan' of normal type, 'Suwon177' and 'Suwon195' of placenta adhesion type (PA) and 'SIG960320-5-1-1' of indehiscent type (ID). PA and ID type are shattering-resistant sesames, and Yangbaek and Ansan are shattering sesames. All the characters were sufficient to the assumption for diallel analysis in this experiment. Over dominance was exhibited by the number of capsules per plant, while partial dominance by plant height, capsule setting stem length, grain yield per plant and shattering rate, complete dominance by the number of branches per plant. Additive effect was higher than dominance in shattering rate. High shattering rate was dominant over low shattering rate. Suwon 195, shattering resistant sesame, showed to have the many recessive genes which reduced the shattering rate of sesame seed. Broad sense heritability for all the characters was more than 0.8. Narrow sense heritability for the number of branches per plant, the number of capsules per plant, grain yield per plant and shattering rate was 0.45 to 0.63, and plant height and capsule setting stem length was more than 0.8.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.2
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• pp.119-124
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• 2005

This study was conducted from March 21 to July 8 in 2004 at JeJu Island to investigate the influences of split nitrogen application times on creeping bentgrass vegetation. Nitrogen rate was 20 kg/10a and it was applied from once to 5 times. The result obtained were summarized as follows; plant height was getting longer as nitrogen was split applied from once to 5 times. So it was longest at 5 times split nitrogen application, but it was no significance from 4 to 5 times. Root length, Minolta SPAD-502 chlorophyll meter reading value, leave and root weight n[e directly proportional plant height response. Degree of land cover Iud density of creeping bentgrass increased as nitrogen was split applied from once to 5 times. But degree of land cover md density of reed decreased. The number of reed species on decreased as nitrogen was split applied from once to 5 times. Then ranking of the dominant weeds were Portulaca oleracea Polygonum hydropiper and Stellaria media (at once split time nitrogen application), Portulaca oleracea, Polygonum hydropiper and Digitaria adscendens (at 2 split times nitrogen application), Digitaria adscendens and Portulaca oleracea Polygonum hydropiper, (at 3 split times nitrogen application), Portulaca oleracea, Poa annua and Polygonum hydropiper (at 4 md 5 split times nitrogen application). These results indicate that the optimum frequency of split N applications is four times for growth of creeping bentgrass in volcanic ash soils of Jeju island.

• Journal of the Korean Applied Science and Technology
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• v.37 no.4
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• pp.839-847
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• 2020

The purpose of this study was to analyze the effects of ankle flexibility, gender, and Q-angle on the ankle joint injury factors during one leg drop landing. For this study, 16 males(age: 20.19±1.78 years, mass: 69.54±10.12 kg, height: 173.22±4.43 cm) and 16 females(age: 21.05±1.53 years, mass: 61.75±6.97 kg, height: 159.34±4.56 cm) in their 20's majoring in physical education using the right foot as their dominant feet were selected as subjects. First, an independent t-test of joint motion and joint moment according to the experience of ankle injury was conducted to determine the effect of physical characteristics on ankle joint injury during one leg drop landing(α = .05). Second, the variable that showed a significant difference through t-test was set as the dependent variable, and the ankle flexibility, gender difference, and Q-angle were designated as independent variables to use Multiple Linear Regression(α =. 05). As a result of this study, it was found that the group that experienced an ankle joint injury was found to use a landing strategy and technique through adduction of the ankle joint and internal rotation of the knee joint, unlike the group without an injury. It was also confirmed that this movement increases the extension moment of the ankle joint and decreases the extension moment of the hip joint. In particular, it was found that the dorsi flexion flexibility of the ankle affects the ankle and knee landing strategy, and the gender difference affects the ankle extension moment. Therefore, it was confirmed that physical characteristics factors affecting ankle joint injuries during one leg drop landing.

• Journal of Korea Water Resources Association
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• v.41 no.4
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• pp.423-432
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• 2008

The local migration or movement behavior of fishes in streams are related to feeding, spawning, growing, dispersing, and refuging. The pale chub (Zacco platypus) is a dominant species that migrates locally and inhabits in river and stream in Korea. However, dams, weirs, culverts and other regulatory structures are physical barriers that limit fish movement and fragment habits and populations. If main stream and off-channel habitats are connected with culverts, they would restrict the small fish as pale chub movement due to the high flow velocities and low depths. But in Korea, there is no experimental study to evaluate the swimming performance of species in Korea. Therefore, it is difficult to proposed that design guidelines for pass fishes through culverts. The purpose of this experimental study is to evaluate the swimming performance of pale chubs. A series of swimming performance test has been used in both of the fixed velocity and the incremental velocity methods in an experimental flume. As a result, the critical swimming speed for pale chub(body length 8.9 cm) was found to be about 0.7 m/s. Therefore, the flow velocity for culvert design in the low flow condition should not be exceed the its swimming ability, especially 0.7 m/s for pale chubs(body length 8.9 cm). And the minimum depth for culvert design in the low flow condition should not be lower than the fish body height add a dorsal fin height.

• Journal of the Korean earth science society
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• v.32 no.1
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• pp.33-45
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• 2011

The characteristics and vertical structure of the rainfall are examined in terms of rain types using TRMM (Tropical Rainfall Measuring Mission) PR (Precipitation Radar) data during the JJA period of 2002-2006 over three different regions; midlatitude region around the Korean Peninsula (EA1), subtropical East Asia (EA2), and tropical East Asia (EA3). The convective rain fraction in the EA1 region is 12.2%, which is smaller by 6% than those in the EA2 and EA3 regions. EA1 shows less frequent convective rain events, which are about 0.5 times as many as those in EA3. EA1 produces the mean convective rain rate of 10.4 mm/h that is about 40% larger than EA2 and EA3 while all regions have similar mean stratiform rain rate. The relationships between storm height and rain rate indicate that the rain rate is proportional to the storm height. Based on the vertical structure of radar reflectivity, EA1 produces deeper and stronger convective clouds with higher rain rate compared to the other regions. In EA3, radar reflectivity increases distinctly toward the land surface at altitude below 5 km, indicating more dominant coalescence-collision processes than the other regions. Furthermore, the bright band of stratiform rain clouds in EA3 is very distinct. In convective rain clouds, the first EOFs of radar reflectivity profiles are similar among the three regions, while the second EOFs are slightly different. The larger variability exists at upper layers for EA1 while it exits at lower levels for EA3.

• Korean Journal of Weed Science
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• v.10 no.3
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• pp.179-185
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• 1990

Five parents which showed differential response to thiobencarb and their $F_1$ hybrids were treated with thiobencarb (S-[(4-chlorophenyl) methyl]diethylcarbamothioate) at 2 and 4 kg ai/ha in order to investigate the inheritance of rice (Oryza sativa L.) to the herbicide. In the analysis of diallel crosses for tolerance of rice cultivars to the herbicide, highly significant GCA (general combining ability) and SCA (specific combining ability) effects were observed at both herbicide rates using the parameters of plant height and dry weight ; the GCA effect being greater than the SCA effect. The additive effects appeared to be more prevalent than dominance effects, and partial dominance was recognized in relation to herbicide tolerance in the different rice cultivars. Higher heritabilities in the narrow and broad senses were observed at 4 kg ai/ha. The heritabilities in the narrow sense for plant height and dry weight were 0.726 and 0. 743, respectively. IR9660-50-3-1 which showed the highest GCA effects seemed to possess more dominant genes related to herbicide tolerance than the other rice cultivars tested.

• Journal of Korean Society of Forest Science
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• v.95 no.4
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• pp.443-452
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• 2006

This study was conducted to investigate the site and growth characteristics of Mackia amurensis stand in natural forest of Mt. Joongwang, Pyongchang-Gun, Gangwon-Do, Korea. The 28 sample plots ($30m{\times}30m$) were established to examine the vegetation and site characteristics for M. amurensis stand. Stem analysis was performed on two sample trees for each of the 5 plots situated at intervals of 100 m by altitude. M. amurensis trees were mainly distributed at the ridge and the slope facing north, with altitudes ranging from 790 to 1,170 m. The M. amurensis grew at relatively deep A-layer of soil with high moisture but infertile. Dominant species with M. amurensis were Quercus mongolica, Fraxinus rhynchophylla, Acer pseudo-sieboldianum, A. pictum subsp. mono, Ulmus davidiana var., japonica, Tilia amurensis, and Populus davidiana. TWINSPAN classified four communities in Mt. Joongwang area; M. amurensis-P. davidiana community (xeric type), M. amurensis-U. davidiana var. japonica community (xeric type), M. amurensis-T. amurensis community (moist type), and M. amurensis-Styrax obassia community (moist type). According to the community type, trees per ha were more abundant in the area of the moist types than the xeric types. Height growth of M. amurensis increased with increasing ages until 10 years, and then decreased thereafter, especially at altitude of 1,020m. M. amurensis showed rapid early growth of height and volume, indicating possible high biomass production under enough light. Growth of M. amurensis increased greatly at about 40 years if released from severe competitions. The rotation age of natural M. amurensis stand was expected for above 50 years.

• Journal of Wetlands Research
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• v.14 no.4
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• pp.667-674
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• 2012

This study was conducted to understand landscape ecological characteristics on habitats of Nannophya pygmaea, an endangered species in South Korea. The ecological characteristics of the habitats were investigated in abandoned paddy fields where N. pygmaea populations have been found in Chungcheongnam-do Kongju, Gyeonggi-do Kwangju and Gyeongsangbuk-do Mungyeong from 2009 to 2010. We surveyed the dominant vegetation, areas, water depth and temperature, and plant height and coverage to compare the wetlands living N. pygmaea and not living N. pygmaea. As a result, habitats of N. pygmaea in all regions were dominated by Salix koreensis community. There is no signigicant difference in the water temperature, plant height and coverage among wetlands of the three different sites, but depth was varied within 2.5~9.5cm. The water depth of habitat was deeper in Gongju than the others. Percentage of open water was 1.7~6% in the wetlands living N. pygmaea. but it did not appear in the wetlands not living N. pygmaea. Therefore, the ecological characteristics of wetlands as abandoned paddy fields should be taken into account for N. pygmaea habitat conservation and restoration.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.250-255
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• 2006

Pinus densiflora is a dominant conifer species in Korea and also distributed in regions of Japan and eastern China. Success in the establishment and productivity of forest tree plantation is largely determined by selection of species and seed source. The provenance tests of Pinus densiflora in Korea are underway. However, the information of the growth performance of Japanese and Chinese provenances are insufficient. Therefore, this study was conducted to evaluate the growth performance of Pinus densiflora Japanese provenances. Data were collected from a provenance trial including established by Korea Forest Research Institude at Chungju in 1970. Six Japanese provenances ($31^{\circ}90^{\prime}{\sim}40^{\circ} 27^{\prime}$ in latitude and $128^{\circ}47^{\prime}{\sim}141^{\circ}80^{\prime}$ in longitude) were included in this trial. Pyeongchang provenance at Kangwon province in Korea was used for reference provenance. At nursery stage, the height and diameter at root collar of six Japanese provenances were smaller than those of Pyeongchang provenance. Among Japanese provenances, Kasahara provenance showed higher growth performance than those of others. The provenance rankings of growth performance were fluctuated until age 11. However, the growth performance of Japanese provenances showed higher than those of reference provenance after age 17. Kirishima-yama provenance showed best growth performance. Simple correlation analysis was conducted to investigate the geographic factors affecting growth performance. The height growth showed negative corelation with latitude of seed origin. Generally, Japanese provenences of Pinus densiflora were well adapted and grown in Chungju. However, it was suggested that further studies on other sites need to generalize the results of this study.

• The Korean Journal of Malacology
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• v.19 no.2
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• pp.143-152
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• 2003

Water temperature during the culturing period was 10.4-25.5$^{\circ}C$ and there was a little difference between rearing sites. Salinity (25.00-31.17 psu) and DO (over 6.13 mg/l) showed reasonable condition for the growth of bay scallop. Concentrations of chlorophyll-a were ranged 1.69-7.40 $^{\mu}$g/l, and they fluctuated monthly in the every sampling site. During the growing period from June to October, dominant phytoplankton species were Ceratium sp. in Nammeon and Hoejin, Chaetoceros sp. in Dolsan. Density of phytoplankton was high in July, August and October, but it was low in September and November. When young bay scallops were cultured for 185 days in Nammyeon, Hoejin and Dolsan, shell heights were grown for 0.19 mm/day, 0.18 mm/day and 0.16 mm/day, respectively, and total weights were increased 0.16 g/day, 0.16 g/day and 0.13 g/day, respectively. Daily growth rates of shell height were 0.606%, 0.581% and 0.549%, and daily growth rates of total weight were 1.972%, 1.857% and 1.746%, respectively. Maximum predicted values of shell height calculated by von Bertalanffy growth model were 52.62 mm, 51.74 mm and 48.91 mm, respectively. Survival rate was the highest in Nammyeon (87.0%), but the rates in Hoejin and Dolsan sharply decreased after November.