• Korean Journal of Animal Reproduction
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• v.25 no.3
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• pp.201-206
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• 2001

This study was carried out to investigate the effects of spring (March~May) and summer (June~August) influencing semen characteristics, frozen-thawed sperm viability and serum testosterone concentration in Yorkshire boars. Results of this study were as follows: 1. There were no significant differences in the semen volume, pH and sperm concentration of sperm-poor fraction of Yorkshire boars between spring and summer. However, sperm concentrations of sperm-rich fractions in spring were higher than those in summer (P＜0.05). 2. Sperm motility and normal acrosome of raw semen in Yorkshire boars did not differ significantly between spring and summer, However, motility and normal acrosome of frozen-thawed sperm were higher in spring season than in summer season (P＜0.05). 3. Serum testosterone concentrations in Yorkshire boars were 4.04 ng/$m\ell$ in spring and 2.85 ng/$m\ell$ in summer. Serum testosterone concentrations in spring were higher than those in summer (P＜0.05). 4. In conclusion, when serum testosterone concentrations in Yorkshire boars were higher, frozen-thawed sperm viability was higher.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.364-368
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• 2006

This experiment was carried out to figure out the $CO_2$ biomass and the growth response of Chinese cabbage and radish grown under the condition of high temperature and high $CO_2$ concentration to provide the information for the coming climatic change. Chinese cabbage and radish were cultivated in spring and autumn seasons under 4 treatments, 'ambient temp.+ambient $CO_2$ conc.', 'ambient temp.+elevated $CO_2$ conc.', 'elevated temp.+ ambient $CO_2$ conc.', and 'elevated temp. +elevated $CO_2$ conc.'. The 'elevated temp,' plot was maintained at 5 higher than 'ambient temp. (outside temperature)'and the 'elevated $CO_2$ cone.' plot was done in 650 ppm $CO_2$. The growth of spring-sown Chinese cabbage was worse than autumn-sown one, and was affected more by high temperature than high $CO_2$. concentration. The $CO_2$ biomass of Chinese cabbage was lower as 25.1-39.1 g/plant in spring-sown one than 54.8-63.4 g/plant of autumn-sown one. Daily $CO_2$2 fixation ability was not significantly different between spring- and autumn-sown Chinese cabbage as 1.9-2.9, 2.7-3.1 kg/10a/day, respectively. The $CO_2$ biomass of radish were 87.4-104.6 /plant in spring-sown one and 51.3$\sim$76.4 g/plant in autumn-sown one. Daily $CO_2$ fixation ability of radish were 6.2-10.1 kg/10a/day in spring-sown one and 4.6-6.9 kg/10a/day in autumn-sown one.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.44-44
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• 2019

Spring sowing of ginseng seeds often results in failure of seedling establishment. Storage condition during winter, sowing time, and seed treatment might effect on germination. Here we tested effects of temperature regimes of seed storage on spring sowing. Dehisced wet or dry ginseng seeds were stored at $2^{\circ}C$, $-2^{\circ}C$, $-3.5^{\circ}C$, or alternating temperature: at $2^{\circ}C$ until December, $-3.5^{\circ}C$ in January, and $2^{\circ}C$ in February, and sowed in March. In overall, emergence rate was dependent on storage temperature, and $-3.5^{\circ}C$ resulted poorest emergence than other conditions. Storage of wet seeds in alternating temperature resulted highest emergence rate. Seed dry also affected on emergence rate, while it was dependent on the storage temperature. In terms of growth, storage at $2^{\circ}C$ as wet seed resulted highest growth, and dried seeds resulted poorer growth than wet seeds. As a modification of alternating temperature, seeds were stored at $2^{\circ}C$ at first, then transferred to $-3.5^{\circ}C$ at Nov 30, Dec 20, and Jan 10, each. When transfer date was delayed, emergence rate was increased. We suggest that seed storage temperature for ginseng should not be decreased below $-2^{\circ}C$, and alternative temperature regime for successful spring sowing could be useful.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.2
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• pp.121-130
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• 2022

This study was conducted to determine the suitable amount of irrigation and fertigation for the growth and yield of spring potatoes (Solanum tuberosum L.). To investigate the effect of soil moisture content on the growth and yield of potato, five irrigation treatments were performed based on soil moisture tension: -10 kPa, -20 kPa, -30 kPa, -40 kPa, and non-irrigation. The growth and yield among the irrigation treatments was the best in the -10 kPa treatment, where the yield increased by 47% compared to the non-irrigation treatment. To determine the standard of additional fertilizer for fertigation cultivation of spring potatoes, seven treatments were performed, including a control (basic fertilization without additional fertilizer), compound fertilizer (NPK) based on 0.5 times the standard amount of fertilizer (NPK 0.5; N-P₂O₅-K₂O: 2.5-2.2-3.25 kg/10a), NPK 0.8 (N-P₂O₅-K₂O: 4-3.5-5 kg/10a), and NPK 1.2 (N-P₂O₅-K₂O: 6-5.3-7.8 kg/10a), and potassium fertilizer of 2 kg (K 2), 5 kg (K 5), and 7 kg (K 7). The growth and yield among the fertilization treatments was highest in the K 5 treatment, where the yield increased by approximately 27% compared to the control. Therefore, this study suggests that irrigation with -10 kPa or fertigation with K 5 during the tuber initiation and tuber filling stage could increase the yield of spring potatoes.

• Asian Journal of Turfgrass Science
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• v.6 no.1
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• pp.39-45
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• 1992

This experiment was undertaken to study effect of fall Fertitizarion on spring regrowth of Korean lawngrass( Zoysia japonica Steud ) Results obtained are summarized as follows : 1. late fall fertilization stimulated the spring regrowth of Korean lawngrass. hut early spring application showed little effect on that 2. The yield of clippings on May 21 was obviously greater in late fertilization plots(treatment C, D and E) than other plots(treatment A, B and control, but there was no significant difference in clipping yields of C, D and F treatment. 3. Both nitrogen and reducing sugar contents of runner fell down in spring. It was suggested thatthese constituents be translocated from runner to other parts during the budding period. 4. The nitrogen content of runner was obviously mote in the plot of late fall fertilization. In contrast to nitrogen, no obvious difference was found in reducing sugar content of runner of seven application date. It was suggested that the roots of plant be still able to absorb to absorb nitrogen under dormancy. .5.From these results. late fall fertilization enhances the development of Korean lawngrass in the following spring. But early spring application shows little effect on spring regrowth.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.3
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• pp.329-341
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• 2005

The purpose of this study is to study the $PM_{2.5}$ source characteristics affecting the Seoul area using a chemical mass balance (CMB) receptor model. This study was also to evaluate the $PM_{2.5}$ source profiles, which were directly measured and developed. Asian Dust Storm usually occurred in the spring, and very high $PM_{2.5}$ concentrations were observed in the fall among the sampling periods. So the ambient data collected in the spring and fall were evaluated. The CMB model results as well as the $PM_{2.5}$ source profiles were validated using the diagnostic categories, such as: source contribution estimate, t-statistic, R-square, Chi-square, and percent of total mass explained. In the spring months, the magnitude of $PM_{2.5}$ mass contributors was in the following order: Chinese aerosol $(31.7\%)>$ secondary aerosols ($22.3\%$: ammonium sulfate $13.4\%$ and ammonium nitrate $8.9\%)>$ vehicles ($16.1\%$: gasoline vehicle $1.4\%$ and diesel vehicles $14.7\%)>$biomass burning $(15.5\%)>$ geological material $(10.5\%)$. In the fall months, the general trend of the $PM_{2.5}$ mass contributors was the following: biomass burning $(31.1\%)>$ vehicles ($26.9\%$: gasoline vehicle $5.1\%$ and diesel vehicles $21.8\%)>$ secondary aerosols ($23.0\%$: ammonium sulfate $9.1\%$ and ammonium nitrate $13.9\%)>$ Chinese aerosol $(10.7\%)$. The results show that the $PM_{2.5}$ mass in the Seoul area was mainly affected by the Chinese area.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.469-490
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• 2003

Atmospheric concentrations of persistent organic pollutants (POPs) were measured at Gosan, Jeju in November 2001 and spring 2002, each time for two weeks. Primary target pollutants were organochlorine pesticides, coplanar polychlorinated biphenyls (co- PCBs), and dioxin/furans listed in the Stockholm Convention adopted in May 2001. Polycyclic aromatic hydrocarbons (PAHs) were also measured in order to understand the overall characteristics of the POPs distribution as well as PM$_{2.5}$, a potent carrier of POPs. In the latter part of the measurement period of November 2001, almost every pollutant of combustion origin including dioxin/furans went high probably due to influence of emissions in the nearby area. The characteristics of atmospheric environment at Gosan in this period were rather close to urban areas far from those of a background area. A severe dust storm swept for three days at the end of the measurement period of spring 2002. However, changes in pollutant concentrations were relatively small except PM$_{10}$. Nevertheless, increases in particulate PAHs and OCDD (octachlorinated dibenzo-p-dioxins), mostly present in fine particles, were observed. Trends in organochlorine pesticide variations were mixed although possible volatilization of DDT residues from soil was inferred from the measurements of spring 2002.2.2.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.2
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• pp.155-160
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• 1996

Spring sown oat crops were grown during early March to late June in 1993~1994. The crops were harvested at different stage of maturity to determine the yield performance, chemical components and net energy value of the plants for silage utilization. The pattern of dry matter accumulation, absolute growth rate(Abs. GR), leaf weight ratio(LWR), stalk diameter(SD) and other growth parameters were analysed to evaluate the suitability of the plant materials for ensiling. The effect5 of wilting treatment and formic acid addition on the quality of silage was also disscused during the experiments. Spring sown oat crops was evaluated as a suitable materials for whole plant silage making. The best qualitative oat silage was obtained at the stage of soti dough to hard dough, when the plant reached 32.2~35.7% in dry matter concentration. Spring sown oat produced 9.43 ton in DM basis, 5.79 ton in TDN and 57.550 MJ-NEL/ha in net energy lactation. Early harvesting of the oat corps needed wilting treatment of the material before ensiling. Under pre-witing treatment (1/2 day) and formic acid addition(0.3%) silage quality point of oat crops harvested at the bloom stage was improved from 58 to 84 point.

• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.1-12
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• 2008

The purpose of this study is to characterize the hydrogeochemical characteristics of hot spring waters and to interpret the source of noble gases and the geochemical environment of the hot spring waters distributed along the eastern area of the Korean peninsula. For this purpose, We carried out the chemical, stable isotopic and noble gas isotopic analyses for eleven hot spring water and fourteen hot spring gas samples collected from six hot spring sites. The hot spring waters except the Osaek hot spring water show the pH range of 7.0 to 9.1. However, the Osaek $CO_2$-rich hot spring water shows a weak acid of pH 5.7. The temperature of hot spring waters in the study area ranges from $25.7^{\circ}C$ to $68.3^{\circ}C$. Electrical conductivity of hot spring waters varies widely from 202 to $7,130{\mu}S/cm$. High electrical conductivity (av., $3,890{\mu}S/sm$) by high Na and Cl contents of the Haeundae and the Dongrae hot spring waters indicates that the hot spring waters were mixed with seawater in the subsurface thermal system. The type of hot springs in the viewpoint of dissolved components can be grouped into three types: (1) alkaline Na-$HCO_3$ type including sulfur gas of the Osaek, Baekam, Dukgu and Chuksan hot springs, and (2) saline Na-Cl type of the Haeundae and Dongrae hot springs, and (3) weak acid $CO_2$-rich Na-$HCO_3$ type of Osaek hot spring. Tritium ratios of the Haeundae and the Dongrae hot springs indicate different residence time in their aquifers of older water of $0.0{\sim}0.3$ TU and younger water of $5.9{\sim}8.8$ TU. The ${\delta}^{18}O$ and ${\delta}D$ values of hot spring waters indicate that they originate from the meteoric water, and that the values also reflect a latitude effect according to their locations. $^3He/^4He$ ratios of the hot spring waters except Osaek $CO_2$-rich hot spring water range from $0.1{\times}10^{-6}$ to $1.1{\times}10^{-6}$ which are plotted above the mixing line between air and crustal components. It means that the He gas in hot spring waters was originated mainly from atmosphere and crust sources, and partly from mantle sources. The Osaek $CO_2$-rich hot spring water shows $3.3{\times}10^{-6}$ in $^3He/^4He$ ratio that is 2.4 times higher than those of atmosphere. It provides clearly a helium source from the deep mantle. $^{40}Ar/^{36}Ar$ ratios of hot spring water are in the range of an atmosphere source.

• Journal of Korean Foot and Ankle Society
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• v.1 no.1
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• pp.38-42
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• 1997

It was well known that arthrodesis of the tarsal joint is an exellent procedure to correct the flatfoot deformity for relieving pain. Recently, concept of the selective tarsal joint fusion instead of the triple fusion was developedto preserve the joint motion. To investigate and compare the effect of the each different tarsal fusion, we measured the strain at the spring ligament, medial roof of the medial longitudianl arch. Five fresh frozen cadevar foot specimens, with distal half of the tibia were utilized. The superomedial portion of the spring ligament complex was dissected from the origin to the insertion. For each specimen, a calibrated open liquid metal strain guage was secured along the length of the superomedial portion. Under the specially devised test rig, measurement of the strain was taken at each test condition from the tare weight 18.2 lb followed by 38.2 lb., 82.2 lb and a maximum loads of 134.6 lb. : 1) unfused condition, 2) isolated subtalar fusion 3) isolated talonavicular fusion 4) combined subtalar and talonavicular fusion 5) triple fusion. Statistics showed that siginificant reduction in strain following the triple fusion, and from the subtalar fusion to triple fusion.