• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.18
• /
• pp.88-123
• /
• 1975

To obtain useful fundamental informations for improving cultural practices of barley, an investigation was made on the influences of different fertilizer level and seeding rate as well as seeding date on yield and yield components and their balancing procedure using barley variety Suwon ＃ 18, and at the same time, 8 varieties including Suwon ＃ 18 were also tested to clarify the varietal responses in terms of their yield and yield components under different seeding date at Crop Experiment Station, Suwon, during the period of 1969 and 1970. The results obtained were summarized as follows; 1. Days to emergence of barley variety Suwon ＃ 18 at Suwon, took 8 to 19 days in accordance with given different seeding date (from Sept. 21 to Oct. 31). Earlier emergence was observed by early seeding and most of the seeds were emerged at 15$0^{\circ}C$ cumulated soil temperature at 5cm depth from surface under the favorable condition. 2. Degree of cold injury in different seeding date was seemed to be affected by the growth rate of seedlings and climatic condition during the wintering period. Over growth and number of leaves less than 5 to 6 on the main stem before wintering were brought in severe cold damage during the wintering period. 3. Even though the number of leaves on the main stem were variable from 11 to 16 depending upon the seeding date. this differences were occurred before wintering and less variation was observed after wintering. Particularly, differences of the number of main stem leaves from September 21 to October 11 seeding date were occurred due to the differences of number of main stem leaves before wintering. 4. Dry matter accumulation before wintering was high in early seeded plot and gradually decreased in accordance with delayed seeding date and less different in dry matter weight was observed after wintering. However, the increment rate of this dry matter was high from regrowth to heading time and became low during the ripening period. 5. Number of tillers per $\m^2$ was higher in early seeding than late one and dense planting was higher in the number of tillers than sparse planting. Number of tillers per plant was lower in number and variation in dense planting, and reverse tendency was observed in sparse planting. By increasing seedling rate in early seeding date the number of tiller per plant was remarkably decreased, but the seeding rate didn't affect the individual tillering capacity in the late seeding date. 6. Seedlings were from early planting reached maximum tillering stage earlier than those from the late planting and no remarkable changes was observed due to increased seeding rate. However. increased seeding rate tends to make it earlier the maximum tillering stage early. 7. Stage of maximum tillering was coincided with stage of 4-5 main stem leaves regardless the seeding date. 8. Number of heads per $\m^2$ was increased with increased seeding rate but considerable year variation in number of heads was observed by increased fertilizer level. Therefore, it was clear that there is no difficulties in increasing number of heads per $\m^2$ through increasing both fertilizer level and seeding rate. This type of tendency was more remarkable at optimum seeding time. In the other hand, seeding at optimum time is more important than increasing seeding rate, but increasing seeding rate was more effective in late seeding for obtaining desirable number of heads per $\m^2$. 9. Number of heads per $\m^2$ was decreased generally in all varieties tested in late seeding, but the degree of decrease by late seeding was lower in Suwon ＃ 18. Yuegi, Hangmi and Buheung compared with Suwon ＃ 4, Suwon ＃ 6, Chilbo and Yungwolyukak. 10. Highly significant positive correlations were obtained between number of head and tillers per $\m^2$ from heading date in September 21 seeding, from before-wintering in October 1 seeding and in all growth period from October 11 to October 31 seeding. However, relatively low correlation coefficient was estimated between number of heads and tillers counted around late March to early April in any seeding date. 11. Valid tiller ratio varied from 33% to 76% and highest yield was obtained when valid tiller ratio was about 50%. Therefore, variation of valid tiller ratio was greater due to seeding date differences than due to seeding rate. Early seeding decreased the valid tiller ratio and gradually increased by delaying seeding date but decreased by increasing seeding rate. Among the varieties tested Suwon ＃ 18, Hangmi, Yuegi as well as Buheung should be high valid tiller ratio not only in late seeding but also in early seeding. In contrast to this phenomena, Chilbo, Suwon ＃ 4, Suwon ＃ 6 and Yungwolyukak expressed low valid tiller ratio in general, and also exhibited the same tendency in late seeding date. 12. Number of grains per spike was increased by increasing fertilizer level and decreased by increasing seeding rate. Among the seeding date tested. October 21 (1969) and October 11 (1970) showed lowest number of grains per spike which was increased in both early seeding and late seeding date. There were no definite tendencies observed along with seeding date differences in respective varieties tested. 13. Variation of 1000 grain weight due to fertilizer level applied, seeding date and seeding rate was not so high as number of grains per spike and number of heads per $\m^2$, but exhibited high year variation. Increased seeding rate decreased the 1000 grain weight. Among the varieties tested Chilbo and Buheung expressed heavy grain weight, while Suwon ＃ 18, Hangmi and Yuegi showed comparatively light grain weight. 14. Optimum seeding date in Suwon area was around October 1 to October 11. Yield was generally increased by increasing fertilizer level. Yield decrease due to early seeding was compensated in certain extent by increased fertilizer application. 15. Yield variations due to seeding rate differences were almost negligible compare to the variations due to fertilizer level and seeding date. In either early seeding or law fertilizer level yield variation due to seeding rate was not so remarkable. Increment of fertilizer application was more effective for yield increase especially at increased seeding rate. And also increased seeding rate fairly compensated the decrease of yield in late seeding date. 16. Optimum seeding rate was considered to be around 18-26 liters per 10a at N-P-K=10.5-6-6 kg/10a fertilizer level considering yield stabilization. 17. Varietal differences in optimum seeding date was quite remarkable Suwon ＃ 6, Suwon ＃ 4. Buheung noted high yield at early seeding and Suwon ＃ 18, Yuegi and Hangmi yielded higher in seeding date of October 10. However, Buheung showed late seeding adaptability. 18. Highly significant positive correlations were observed between yield and yield components in all treatments. However, this correlation coefficient was increased positively by increased fertilizer level and decreased by increased seeding rate. Significant negative correlation coefficients were estimated between yield and number of grains per spike, since increased number of heads per m2 at the same level of fertilizer tends to decrease the number of grains per spike. Comparatively low correlation coefficients were estimated between 1000 grain weight and yield. 19. No significant relations in terms of correlation coefficients was observed between number of heads per $\m^2$ and 1000 grain weight or number of grains per head.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.9 no.2
• /
• pp.218-226
• /
• 1998

This study aims at investigating the effects of psychostimulant on functional cerebral localization during the attentional tasks in ADHD. Inclusional subjects were 13 boy between 6-12 years old who met the DSM-IV criteria for ADHD. In each patient, there was a drugfree period(without methyphenidate) and a drug-loaded period(with oral methylphenidate administration), and within each period there was a resting state and a stimulated state with TOVA. Comparisons were made by measuring the amplitudes of four bands(${\alpha}$, ${\beta}$, ${\delta}$, ${\theta}$) of quantitative EEG to see if there were any differences between the drug-free period(resting and stimulated) and the drug-loaded period(resting and stimulated). In the resting state, there was no difference between the drug-free and drug-loaded periods. In the stimulated state with TOVA, the presence of methylphenidate induced significant changes in the theta to beta ratio(${\theta}/{\beta}$) in the right frontal, right parieto-occipital, and left temporal-parietal areas in contrast to the drugf-ree period. These data suggest that methylphenidate shows electrophysiological influences on cerebral topographical activities during the attentional tasks in ADHD.

• Korean Journal of Environment and Ecology
• /
• v.21 no.4
• /
• pp.336-346
• /
• 2007

This study was conducted to evaluate the vegetation structure of 34 plots for inspection(plot unit: $100m^2$)of evergreen broad-leaved forest in Dongbaekdongsan(Mt.), Jeju-do, Korea. In accordance with the results of TWINSPAN and mean importance percentage analysis, the target forest was aged $28{\sim}52$, and classified into seven community types in total: Ilex rotunda community, Castanopsis sieboldii community, Castanopsis sieboldii-Quercus glauca community, Quercus glauca-Castanopsis sieboldii community, Quercus glauca community, Quercus glauca-Camellia japonica community, and Quercus glauca-Styrax japonica community. According to the results of importance percentage analysis and DBH class distribution of major woody species, the vegetational aspects showed that the dominant species were Castanopsis sieboldii and Quercus glauca in the canopy layer and Camellia japonica in the subordinate layer. Ilex rotunda and Quercus glauca-Styrax japonica community were damaged vegetation in the canopy layer. According to the index of Shannon's diversity in the six communities including the dominant species - Quercus glauca and Castanopsis sieboldii, their species diversity degree was $0.8745{\sim}1.3018$ and that of Ilex rotunda community was the lowest 0.7619. Camellia japonica, Eurya japonica, Ilex rotunda, Trachelospermum asiaticum var. intermedium, Ardisia crenata appeared in all the seven communities. In addition, Litsea coreana and Cinnamomum japonicum as well as Neolitsea serica presumed as climax species in the warm temperate climate also appeared and the constancy ratio of Cinnamomum japonicum was more than 80%. As a result, the target forest in Dongbaekdongsan(Mt.) was mainly compose of Castanopsis sieboldii and Quercus glauca in the canopy layer as a mixed vegetational pattern, and Cameliia japonica was dominant in the subordinate layer. Continuous monitoring was required, since Camellia japonica was strong in the subordinate layer in contrast to the weakness of Litsea coreana and Neolitsea serica reported as the species of climax stage in the forest with Evergreen Broad-leaved Vegetation at a viewpoint of successional direction.

• Journal of Korean Society of Transportation
• /
• v.34 no.1
• /
• pp.1-14
• /
• 2016

In the recent years, the internet has become accessible without limitation of time and location to anyone with smartphones. It resulted in more convenient travel information access both on the pre-trip and en-route phase. The main objective of this study is to conduct a stationary test for traffic information web/mobile application access indexes from TCS (Toll Collection System); and analyzing the relationship between the web/mobile application access indexes and actual traffic volume on expressways, in order to analyze searching behavior of expressway related travel information. The key findings of this study are as follows: first, the results of ADF-test and PP-test confirm that the web/mobile application access indexes by time periods satisfy stationary conditions even without log or differential transformation. Second, the Pearson correlation test showed that there is a strong and positive correlation between the web/mobile application access indexes and expressway entry and exit traffic volume. In contrast, truck entry traffic volume from TCS has no significant correlation with the web/mobile application access indexes. Third, the time gap relationship between time-series variables (i.e., concurrent, leading and lagging) was analyzed by cross-correlation tests. The results indicated that the mobile application access leads web access, and the number of mobile application execution is concurrent with all web access indexes. Lastly, there was no web/mobile application access indexes leading expressway entry traffic volumes on expressways, and the highest correlation was observed between webpage view/visitor/new visitor/repeat visitor/application execution counts and expressway entry volume with a lag of one hour. It is expected that specific individual travel behavior can be predicted such as route conversion time and ratio if the data are subdivided by time periods and areas and utilizing traffic information users' location.

• Korean Journal of Environment and Ecology
• /
• v.28 no.5
• /
• pp.500-509
• /
• 2014

To prevent freezing of the road by fallen snow, Calcium chloride($CaCl_2$) as a deicer is used to very often and it can be harmful to roadside trees. This study was conducted to investigate the effects of Calcium chloride($CaCl_2$) as a deicer on growth and physiological traits of Acer triflorum according to different concentration of $CaCl_2$. We measured growth, chlorophyll contents, gas exchangement characteristics, chlorophyll fluorescence and mineral nutrition concentration in plant and soil. The experimental group was composed of four treatments including 0mM(control), 9mM(0.5 %), 18mM(1.0 %), 54mM(3.0 %). Before germinating new shoot, the dissolution of $CaCl_2$ was irrigated twice interval of a week. At 30 days after treatment, all treatments decreased total cholorophyll content, photosynthetic rate, transpiration rate, stomatal conductance and photochemical efficiency($F_v/F_m$) with increasing concentration of $CaCl_2$ and especially, they significantly reduced in 3.0 % treatment. In contrast, chlorophyll a/b ratio increased with an increase of $CaCl_2$ concentration and water use efficiency increased in 1.0 % and 3.0 % treatments. At 50 days after treatment, all treatments were decreased in chl a, chl b, total chlorophyll content, carotenoid content, photosynthetic capacity, photochemical efficiency($F_v/F_m$) and quantum yield of photosystem II(${\Phi}_{PSII}$) compared with control and 3.0 % treatments were withered. $Ca^{2+}$ and $Cl^-$ were accumulated in leaves and soil, which inhibited water absorption and electron transport and it caused the reduction of height growth rate more than 50 %. Although there was a little difference according to time and $CaCl_2$ concentration, all treatments decreased in growth rate and physiological activity slowed down. As time passed, these results got worse. Therefore we need to take a measure earlier in order to minimize damage of trees.

• Investigative Magnetic Resonance Imaging
• /
• v.22 no.1
• /
• pp.1-9
• /
• 2018

Purpose: This study was designed to optimize the flip angle (FA) and scan timing of the hepatobiliary phase (HBP) using the 3D T1-weighted, gradient-echo (GRE) imaging with controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA) technique on gadoxetic acid-enhanced 3T liver MR imaging. Materials and Methods: Sixty-two patients who underwent gadoxetic acid-enhanced 3T liver MR imaging were included in this study. Four 3D T1-weighted GRE imaging studies using the CAIPIRINHA technique and FAs of $9^{\circ}$ and $13^{\circ}$ were acquired during HBP at 15 and 20 min after intravenous injection of gadoxetic acid. Two abdominal radiologists, who were blinded to the FA and the timing of image acquisition, assessed the sharpness of liver edge, hepatic vessel clarity, lesion conspicuity, artifact severity, and overall image quality using a five-point scale. Quantitative analysis was performed by another radiologist to estimate the relative liver enhancement (RLE) and the signal-to-noise ratio (SNR). Statistical analyses were performed using the Wilcoxon signed rank test and one-way analysis of variance. Results: The scores of the HBP with an FA of $13^{\circ}$ during the same delayed time were significantly higher than those of the HBP with an FA of $9^{\circ}$ in all the assessment items (P < 0.01). In terms of the delay time, images at the same FA obtained with a 20-min-HBP showed better quality than those obtained with a 15-min-HBP. There was no significant difference in qualitative scores between the 20-min-HBP and the 15-min-HBP images in the non-liver cirrhosis (LC) group except for the hepatic vessel clarity score with $9^{\circ}$ FA. In the quantitative analysis, a statistically significant difference was found in the degree of RLE in the four HBP images (P = 0.012). However, in the subgroup analysis, no significant difference in RLE was found in the four HBP images in either the LC or the non-LC groups. The SNR did not differ significantly in the four HBP images. In the subgroup analysis, 20-min-HBP imaging with a $13^{\circ}$ FA showed the highest SNR value in the LC-group, whereas 15-min-HBP imaging with a $13^{\circ}$ FA showed the best value of SNR in the non-LC group. Conclusion: The use of a moderately high FA improves the image quality and lesion conspicuity on 3D, T1-weighted GRE imaging using the CAIPIRINHA technique on gadoxetic acid, 3T liver MR imaging. In patients with normal liver function, the 15-min-HBP with a $13^{\circ}$ FA represents a feasible option without a significant decrease in image quality.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.9
• /
• pp.803-810
• /
• 2009

This study is conducted to examine spatial variations of Dissolved Organic Matter (DOM) in stream and waste waters of the different watershed areas (agricultural, residential, and industrial complex area) by using fluorescence 3D-EEMs (3 Dimensional Excitation Emission Matrix Spectroscopy). Furthermore, the research investigates the changes of DOM characterization by synchronous and 3D-EEMs during a rainfall event. The characterizations of DOM obtained by 3D-EEMs show two noticeable peaks at humic and protein-like regions. Humic-like substances (HLS) are found in rural and urban areas, and humic and protein-like substances (PLS) are shown in industrial area. According to the fluorescence peak $T_1:C_1$ ratios, it is observed that high amount of HLS was discharged from Banweol Industrial Complex (3TG). Additionally, linear relationships (Regression rate, $r^2$=0.65, $r^2$=0.66) have been shown between PLS (peak $T_1,\;B_1$) and biochemical oxygen demand (BOD), which indicates the impact of sewage. For the rainfall event (30 mm), no remarkable difference of DOM was found at rural area except increment of fluorescence intensity comparing dry period. In contrast, HLS at urban area is highly discharged within 30 minutes from the beginning of rainfall. Also, there are high influences of HLS and PLS within 20 minutes at industrial complex (4TG). Fluorescence 3D-EEMs has not only verifies a watershed of DOM origination but also monitors diffuse and point source impacts.

• Journal of the Korean earth science society
• /
• v.28 no.3
• /
• pp.311-323
• /
• 2007

The Yellow and East China seas received a vast amount of sediment $(>10^9ton/yr)$, which comes mainly from the Changjiang and Huanghe rivers of China and the Korean rivers. However, there are still no direct sedimentological-geochemical indicators, which can distinguish these two end-members (Korean and Chinese river sources) in these seas. The purpose of this study is to provide the potential geochemical-tracers enabling these river materials to be identified within the sediment load of the Yellow and East China seas. The compositions of major elements (Al, Fe, Mg, K, Ca, Na, and Ti) of Chinese and Korean river sediments were analyzed. To minimize the grain-size effect, furthermore, bulk sediments were separated into two groups, silt $(60-20{\mu}m)$ and clay $(<20{\mu}m)$ fractions, and samples of each fraction were analyzed for major and strontium isotope $(^{87}Sr/^{86}Sr)$ compositions. In this study, Fe/Al and Mg/Al ratios in bulk sediment samples, using a new Al-normalization procedure, are suggested as an excellent tool for distinguishing the source of sediments in the Yellow and East China seas. This result is clearly supported by the concentrations of these elements in silt and clay fraction samples. In silt fraction samples, Korean river sediments have much higher $^{87}Sr/^{86}Sr$ ratio $(0.7229{\sim}0.7253)$ than Chinese river sediments $(0.7169{\sim}0.7189)$, which suggests the distribution pattern of $^{87}Sr/^{86}Sr$ ratios as a new tracer to discriminate the provenance of shelf sediments in the Yellow and East China seas. On the basis of these geochemical tracers, clay fractions of southeastern Yellow Sea mud (SEYSM) patch may be a mixture of two sediments originated from Korea and China. In contrast, the geochemical compositions of silt fractions are very close to that of Korea river sediments, which indicates that the silty sediments of SEYSM are mainly originated from Korean rivers.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.7
• /
• pp.892-901
• /
• 2009

This study confirmed depletion efficiency of nitrite when incubate lactic acid bacteria was isolated from commercial Chinese cabbage pickles (Baechu kimchi), pickled ponytail radishes (Chongkak kimchi), radish cube kimchi (Kaktugi) and pickled Wakegi (Pa kimchi) at temperatures of $15^{\circ}C$ and $25^{\circ}C$. At $15^{\circ}C$, lactic acid bacteria isolated from commercial kimchi depleted nitrite actively except Leuconostoc mesenteroides subsp. mesenteroides and Leuconostoc paramesenteroides. In particular, Leuconostoc mesenteroides subsp. dextrinicum and Leuconostoc lactis depleted nitrite by very actively without period adaptation in nitrite. Lactobacillus sake, Lactobacillus plantarum, Lactobacillus casei subsp. pseudoplantarum, and Lactobacillus coryniformis subsp. torquens depleted nitrite very actively after 1 day. L. mesenteroides subsp. mesenteroides depleted nitrite relatively actively after 2 days pass. In contrast, L. paramesenteroides displayed very low nitrite depletion ratio compared to other species. At $25^{\circ}C$, all lactic acid bacteria isolated from commercial kimchi did not need adapting period in nitrite, and depleted nitrite very actively except L. paramesenteroides. Also, all lactic acid bacteria except L. mesenteroides subsp. mesenteroides and L. paramesenteroides nitrite of more than 90% after 1 day, and L. mesenteroides subsp. mesenteroides depleted nitrite of more than 90% after 2 days. However, because L. paramesenteroides was not active even at $25^{\circ}C$, nitrite depletion efficiency was very low compared to other species. On the other hand, the same species of Lactobacilli and Leuconostocs except L. mesenteroides subsp. mesenteroides and L. paramesenteroides of other kimchi origin at $15^{\circ}C$ as well as $25^{\circ}C$ by vitality depleted nitrite very actively without statistically significant difference (p<0.05).

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.11
• /
• pp.1658-1664
• /
• 2014

Sprout vegetables containing various types of polyphenols and flavonoids, are known to have anti-inflammatory, antioxidant, cholesterol-lowering, and anti-obesity activities. However, there have been few reports on the anti-diabetic efficacy of sprout vegetables. Here, we investigated the anti-diabetic effects of sprout extract obtained from buckwheat, beet, rape, broccoli, kohlrabi, red young radish, and dachai, in high fat diet (HFD) and streptozotocin (STZ)-induced type II diabetes mellitus mice. The mice were fed a HFD (60% calories as fat) for 8 weeks prior to intraperitoneal injection with STZ (75 mg/kg). The diabetic mice were divided into four groups: standard diet (STD, 10% calories fat), HFD, HFD with sprout extract (SPE) and HFD with metformin (MET). After 4 weeks, body weight gain was much lower in both SPE and MET groups than in HFD group. In contrast, there was no difference experiment groups regarding food intake ratio. The level of fasting blood glucose was significantly lower in the SPE and MET groups compared to the HFD group. Oral glucose tolerance and insulin tolerance in the SPE and MET groups were significantly ameliorated in comparison to the HFD group. The concentrations of serum total cholesterol, triglycerides, and LDL cholesterol in the SPE and MET groups were remarkably reduced in comparison to the HFD group, and HDL cholesterol concentration was higher in the SPE and MET groups than in the HFD group. Glutamate oxaloacetate transaminase and glutamate pyruvate transaminase levels were between SPE and HFD groups. The serum insulin and leptin concentrations were significantly reduced in both the SPE and MET groups compared to the HFD group. Therefore, these results indicate that sprout extract could improve insulin resistance and attenuate blood glucose level in HFD/STZ-induced type II diabetes mellitus mice. We conclude that this study may provide positive insights into sprout extract as a functional food ingredient for treatment of type II diabetes mellitus.