• Korean Journal of Weed Science
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• v.12 no.2
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• pp.124-131
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• 1992

Not only reducing the carry-over effects of quinclorac [3, 7-dichloro-8-quinoline carboxylic acid] used in paddy field to some following vegetable crops but also rationalizing agro-ecology conservation and farm economy, the reducing feasibility of application rates by various cropping patterns and application timing after rice seeding and transplanting. Four cropping patterns namely dry direct seeding(DDS), flooded direct seed(FDS), transplanting of 8 days old early seedlings(EST) and 25 days old machinery seedling(MST) were experimented with 7 application timings as 0, 5, 10, 15, 20, 25, 30 days after seeding/transplanting and 9 levels of application rates as 0, 75, 150, 225, 300, 375, 450, 525, and 600g ai/ha of the chemical, respectively. Within the maximum permitted limit of rice phytotoxicity, the minimum application rate of quinclorac to complete control of Echinochloa crus-galli as influenced by various cropping patterns with application timing could be evaluated as follows : A. Dry direct seeding : The minimized application rate at application timing upto 10 days after seeding (DAS) was counted 150g ai/ha, and delaying upto 15-30 DAS, the rates were increased upto 225-525g ai/ha. B. Flooded direct seeding and transplanting : The application rates were minimized 75g ai/ha at application timing upto 10 days after seeding/transplanting(DAS/T), 150g ai/haupto 15 DAS/T, and 225g ai/ha at later than 20 DAS/T, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.4
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• pp.216-222
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• 2002

Field experiments were conducted to investigate the effect of various cultural practices on methane($CH_4$) emission in tillage and no-tillage practice in a clayey paddy soil from 1998 to 2000. The factors evaluated in tillage and no-tillage methods were types of nitrogen fertilizers, application method of chemical fertilizers, rice straw application and cultivation method. Of the nitrogen fertilizers, the amount of $CH_4$ emission in ammonium sulfate plot was the lowest, regardless of tillage and the application method. 26.4~41.1% of reduction by ammonium sulfate compared with urea. But in no-tillage which have problem of poor rice yield than tillage, coated urea was more effective nitrogen fertilizer because that showed similar $CH_4$ emission and highest rice yield at 80% of dosage of nitrogen. No-tillage plot emitted lower $CH_4$ than tillage plot where the fertilizers were incorporated. On the contrary, no-tillage plot showed a little higher $CH_4$ emission compared with tillage plot for the surface application. When rice straw was applied, no-tillage practice reduced methane emission by 26.6% compared with tillage practice, but showing a little difference of 10.7% in no application. With cultivation method, no-tillage practice reduced methane emission 26.6% compared with tillage for the 30-d-old seedling transplanting. But for the dry direct seeding practice, no-tillage was a less effective because considerable amounts of rice straw incorporated by tillage were more decomposed aerobically in the soil and emitted as $CO_2$ to the atmosphere with flooding in no-tillage soil.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.3
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• pp.264-271
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• 1988

This experiment was carried out to investigate the effects of long-term applications of organic matters on the chemical properties and on the application levels of nitrogen in Fluvio-Alluvial plain of Jeonbug series. The amounts of application of rice straw and compost, the sources of organic matters, were 500 and 1,000 kg/10a in combined with the different nitrogen levels of 0.15 and 20 kg/10a, respectively. The results obtained from the 9 year's experiment during 1979 to 1987 were summarized as follows: I. In long-term application of Organic matter the soil pH showed the lowest value in the 3rd-4th year at rice straw and 5th-6th year at compost but it varied less in control plot for 9 years. 2. Organic matter content in the soils was gradually increased by yearly application of organic matter, while it was higher in rice straw than in compost since the 5th year. 3. The contents of available silica and available phosphate in soil were rapidly increased by long-term application of organic matter and it was especially higher in rice straw than compost, but it was gradually decreased in control plot. 4. The contents of exchangable cations (Ca, Mg and K) and the total nitrogen were increased by long-term application of organic matter they were in rice straw than in compost. But they showed decreasing tendency in control plot. 5. The soil Eh was lower in order of rice straw, compost and control plot however application of orgnic matter resulted in increasing soil Eh due to the rapid reduction of soil from panicle formation to heading stage in rice cultivation. 6. The number of panicles per $m^2$ and the number of granis per panicle were increased by increment of nitrogen levels in all treatments and especially largest in rice straw application. But 1,000 grain weight increased in low nitrogen level with long-term applications of organic matter. 7. It was estimated that the application levels of nitrogen by long-term application of organic matter were 21, 24 and 20 kg/10a for 1st-3rd, 4th-6th and 7th-9th year in rice straw application, and 16 and 19 kg/10a for 1st-3rd and 4th-9th year in compost application, respectively.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.23 no.1
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• pp.1-19
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• 2018

In order to compare significant wave height (SWH) data from multi-satellites (GFO, Jason-1, Envisat, Jason-2, Cryosat-2, SARAL) and SWH measurements from Ieodo Ocean Research Station (IORS), we constructed a 12 year matchup database between satellite and IORS measurements from December 2004 to May 2016. The satellite SWH showed a root mean square error (RMSE) of about 0.34 m and a positive bias of 0.17 m with respect to the IORS wave height. The satellite data and IORS wave height data did not show any specific seasonal variations or interannual variability, which confirmed the consistency of satellite data. The effect of the wind field on the difference of the SWH data between satellite and IORS was investigated. As a result, a similar result was observed in which a positive biases of about 0.17 m occurred on all satellites. In order to understand the effects of topography and the influence of the construction structures of IORS on the SWH differences, we investigated the directional dependency of differences of wave height, however, no statistically significant characteristics of the differences were revealed. As a result of analyzing the characteristics of the error as a function of the distance between the satellite and the IORS, the biases are almost constant about 0.14 m regardless of the distance. By contrast, the amplitude of the SWH differences, the maximum value minus the minimum value at a given distance range, was found to increase linearly as the distance was increased. On the other hand, as a result of the accuracy evaluation of the satellite SWH from the Donghae marine meteorological buoy of Korea Meteorological Administration, the satellite SWH presented a relatively small RMSE of about 0.27 m and no specific characteristics of bias such as the validation results at IORS. In this paper, we propose a conversion formula to correct the significant wave data of IORS with the satellite SWH data. In addition, this study emphasizes that the reliability of data should be prioritized to be extensively utilized and presents specific methods and strategies in order to upgrade the IORS as an international world-wide marine observation site.

• Journal of Animal Environmental Science
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• v.18 no.2
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• pp.123-130
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• 2012

This study was conducted to investigate the effects of cattle slurry on productivity of whole crop barley and Italian ryegrass and environmental pollution in paddy land. Cropping systems used in this study were consisted of two designs, such as whole crop barley applied with cattle slurry (WCB) and Italian ryegrass applied with cattle slurry (IRG). The field experiments were conducted on the clay loam at Backsanmyun, Kimje, Chunlabukdo province in Korea for three years (May 2006 to Apr. 2009). This study was arranged in completely randomized design with three replicates. The yields of WCB and IRG were 7,520 kg/ha and 10,320 kg/ha, respectively. The yields of IRG significantly increased as compared with that of WCB (p<0.05). The yield of Italian ryegrass in 1st cutting time was about 2-fold higher than that of 2nd cutting time. The contents of crude protein of IRG were higher than that of WCB. However, the contents of NDF, ADF and TDN were no difference between WCB and IRG treatments. The pH, and contents of T-N, $P_2O_5$ and organic matter (OM) in soil samples collected at the end of the experiment increased as compared with those at the beginning of the experiment (p<0.05). After the end of experiment, the concentrations of CEC (Ca, Na, Mg and K) in soil samples collected at the end of the experiment were remarkably higher than those at the beginning of the experiment (p<0.05). The concentrations of $NH_4$-N, $NO_3$-N, $PO_4$-P, Cl, Ca, K, Mg and Na in leaching water in paddy land cultivated with WCB and IRG were no difference between WCB and IRG treatments.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.3
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• pp.187-194
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• 1985

This field experiment was carried out to determine the effects of thirteen different fertilizer levels of nitrogen(N), phosphorus($P_2O_5$) and potassium($K_2O$) on the content of crude protein, crude fiber, mineral constituents of product and tree growth forest pasture with 40-50% shading. The experiment was arranged as a randomized block design and performed in the suburban forest of Suweon in 1984. The results obtained are summarized as follows: 1. Crude protein content and total protein yield were higher in the plot of 28 and 42kg $N/_{10a}$, regardless of $P_2O_5\;and\;K_2O$ level, while those were the lowest in zero fertilizer and N-zero fertilizer plots. 2. The contents of lignin and silica were significantly low in the high N fertilizer level, and the contents of NDF, ADF, cellulose and hemicellulose were not affected by different fertilizer levels. However, the content of crude fiber tended to be low with high N, regardless of $P_2O_5\;and\;K_2O$. 3. The contents of N,K and $SiO_2$ of grasses were influenced by different fertilizer levels. However, those of P,Ca,Ma and Na showed little differences. 4. The recovery percentage of NPK was higher in the plot of standard fertilizer level with 28-20-24 kg/10a, and higher recovery percentage was observed in $K_2O$, followed by N and $P_2O_5$ in that order. 5. The growth of tree was increased as the level of N fertilizer was increased, but no such trend was noted by $P_2O_5\;and\;K_2O$ levels. 6. Crude protein, crude fiber, some mineral contituents of grasses, and growth of tree were influenced by N level, regardless of $P_2O_5\;and\;K_2O$. And the optimum fertilizer level of $N-P_2O_5-K_2O$ seemed to be 28-20-24 kg/10a for the production of grasses with higher quality and more yield in the forest.

• Journal of Distribution Science
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• v.9 no.3
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• pp.5-14
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• 2011

One of the new roles of modern retail stores is to supply consumers with a memorable experience. In Korea, enhancing a store's environment so that customers remember a unique shopping experience is recognized as a sound strategy for strengthening the store's competitiveness. Motivated by this incentive, awareness of the experience-store concept is starting to increase in various categories of the retail industry. However, many experience stores, except in a few cases, have yet to derive a significant profit, explaining why Korean consumers are somewhat unfamiliar with, yet fascinated by, the experience stores that now exist in the country. Consumer satisfaction directly, and indirectly, affects a company's future profit and potential financial gain; customer satisfaction also affects loyalty. Therefore, knowing the significant factors that increase satisfaction and loyalty is essential for any company, in any field, to be able to effectively differentiate itself from the competition. Intrigued by increased competition opportunities, most Korean companies have adopted experience-store marketing strategies. When establishing the most effective processes for increasing sales and achieving a sustainable competitive advantage of a new concept, companies should consider certain factors that influence consumers' ability to accept new concepts and ideas. The Technology Acceptance Model (TAM) is a theory that models how people accept new concepts. TAM proposes the following two factors that influence a person's decisions about how, and when, he or she will use a new product: "perceived usefulness" and "perceived ease of use." Much of the existing research has suggested that a person's character also affects the process for accepting new ideas. Such personal character attributes as individual preferences, self-confidence, and a person's values, traits, and/or skills affect the process for willingly consenting to try something new. It will be meaningful to establish how the TAM theory's components, as well as personal character, affect individuals accepting the experience-store concept. To that end, as it pertains to an experience store, the first goal of the study is to examine the influence of innovative factors (perceived usefulness and perceived ease of use) on satisfaction and loyalty. The second objective is to define the moderate effect of consumers' personal characteristics on the model. The proposed model was tested on 149 respondents who were engaged in leisure sports activities and bought sports outdoor garments and equipment. According to the study's findings, the satisfaction and loyalty of an experience store can be explained by perceived usefulness and perceived ease of use, with the study's results demonstrating the stronger of the two factors being "perceived ease of use." The study failed to explain the effects of a person's character on the model. In conclusion, when the companies that operate the experience stores execute their marketing and promotion strategies, they should stress the stores' "ease of use" product components. Additionally, it can be extrapolated from the study data that since the experience-store idea is still relatively unfamiliar to Korean consumers, most customers are not yet able to evaluate, nor take a position regarding, their respective attitudes toward experience stores.

• Korean Journal of Plant Resources
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• v.31 no.4
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• pp.378-383
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• 2018

This study was carried out to investigate the optimum cultivation distance for high yielding cultivation of the new variety of Gomchwi in highland and lowland. The test material was used 'Sammany' variety and the area was cultivated with a highland of 750 m above sea level and a lowland of 20 m above sea level. The planting distance was 5 treatments of $20{\times}20cm$, $20{\times}30cm$, $30{\times}30cm$, $35{\times}40cm$ and $40{\times}40cm$, and the plant was cultivated at 35% shading net in the open field. The annual growth of 'Sammany' variety was higher in the highland than in the lowland, but the number of leaves was higher in the lowland than that in the highland. The leaf number per plant was the highest in the $40{\times}40cm$ plot and the more the planting distance was, the more tendency was. However, the leaf weight per plant was higher in the highland than in the lowland. The number of leaves per 10a were higher in the lowland than that of highland and the tendency was more as the planting distance was narrower. Yields were slightly higher in the highland than that of lowland and the highest treatment plot was 2,983 kg/10a in $20{\times}20cm$. In the second year, the growth was high in the highland, and the highland was high in the leaf number and leaf weight and the same tendency in the yields. Among the planting distances, Yields in both areas were the highest in the $20{\times}20cm$ treatment, with 3,369 kg/10a in lowland and 7,257 kg/10a in highland. The growth of the third year was slightly better in the highland than that of the lowland but the difference was not significant. However, the number of leaves and leaf weight per plant were higher in the lowland than that of highland. And, in terms of leaf number and yield per 10a, it was also higher in the lowland than that in the highland. The narrower the planting distance was increased yields, and the highest yield was 6,051 kg/10a in $20{\times}20cm$. The lowland was high in yield until the third year, but the highland was the highest in the second year and decreased slightly in the third year. The narrower the planting distance in the both areas, the higher the yield, and the leaf size tended to be small.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.2
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• pp.185-192
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• 1987

A green house experiment was conducted to find out the acetylene reducing and $N_2$-fixing activity from photosynthetic and aerobic heterotrophic nitrogen fixing microorganisms in submerged paddy soil under different agricultural locality, soil series, soil texture, soil type, and drainage condition in which samples taken from without nitrogen treatment plot of NPK trials on 16 sites of the farmer's field. The results obtained were summarized as follows: 1. The highest acetylene reducing activity was observed at 7 days after incubation in the light condition (photo synthetic microbes+heterotrophic bacteria) while it was observed at 35 days incubation in the dark condition (heterotrophic bacteria). 2. Among the soil series, photosynthetic nitrogen fixing activity was pronounced more in Jangae, Ogcheon and Hwadong series while lower was obtained in Buyong and Daejeong series. Aerobic heterotrophic nitrogen fixing activity was high in Buyong and Daejong series. 3. Estimated amount of $N_2$-fixation from acetylene reducing activity was equivalented to 3.0 mg in light condition and 4.9 mg/100g/105 days in dark condition. 4. Among the agricultural locality, photosynthetic nitrogen fixing activity was high in rather warm southern part while heterotrophic nitrogen fixing activity was predominated more in mountainous area and Chungcheong continental. 5. Photosynthetic nitrogen fixing activity was predominated in high productive soil while aerobic heterotrophic nitrogen fixing activity was pronounced more in crose coarse sandy soil. 6. The soils properties of high photosynthetic nitrogen fixing activity were constituted of poorly or imperfectly drained clay or clay loam soil while heterotrophic nitrogen fixing activity was pronounced more in well to moderately well drained sandy or sandy loam soil.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.4
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• pp.329-336
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• 1989

A series of green house experiment was conducted to find but the effect of fertilizer application and inoculation of rhizobium on the changes of amide-N, ureide-N and $NH_4-N$ concentration in stem and root exudates of soybean plant growth. The results obtained were summarized as follows ; 1. Five strains of indigenous Rhizobium japonicum-nitrogen fixing activity($C_2H_2$-reducing activity) was more than 6.4 to 20.1 nmole/hr/tube-were identified from 37 soil samples in 22 areas of farmers field throughout country. 2. These identified 5 strains of rhizobium were obtained high nitrate reductase but low ammonium and nitrite oxidase activities. Among 5 strains of rhizobium the Rhizobium japonicum RjK-134 was applied for this green house experiment. 3. Dry matter yield was increased by the combination of inoculation of Rhizobium japonicum RjK-134 with no fertilizer and without nitrogen fertilizer application. However, dry matter yield was decreased with application of N and NPK with inoculation of rhizobium. 4. The concentrations of amide-N and ureide-N were increased in xylem sap than that of root exudate and higher concentration was obtained ar 30 days after planting than flowering stage (45 days after planting). 5. The combination of NPK application with inoculation of Rhrizobium japonicum RjK-134 enhanced the increase of amide-N and ureide-N concentration in xylem sap and root exudate. 6. High ammonium-N concentration in xylem sap and root exudate were obtained in combination with without-fertilizer under no inoculation of rhizobium and N and NPK application with inoculation of rhizobium.