• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.183-183
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• 2017

In the early part of rice growth, root volume primarily limits the amount of plant-accessible nitrogen (N). Therefore, knowledge of the root development is important for modeling N uptake of rice. The timing when the volume of rhizosphere cover the whole soil is also important to carry out timely top dressing. However, information about initial root expansion and associated N uptake is limited due to intrinsic technical difficulties in assessing below-ground processes. Some studies, however, showed a close relationship between below-ground root and above-ground leaf development, suggesting a possibility that above-ground attributes could serve as surrogates for the root processes. In this study, we investigated the relationship between below-ground and above-ground development of rice. Field experiments were conducted where we cultivated Koshihikari (a leading cultivar in Japan) for four different cropping schedules in 2012. In 2016, Gimbozu (HEG4) and three flowering time mutant lines of Gimbozu (X61 (se13), HS276 (ef7), DMG9 (se13, ef7)) were examined for a single season. Experiments were performed with three replications in a completely randomized design. We monitored ammonium-N concentration ([NH4+-N]) in soil solution by repeatedly taking samples from a porous tubing (10-cm long) vertically inserted at the most distant point from surrounding rice hills. Samples were taken in triplicate (= triplicate tubes) and every three days from transplanting in each experimental unit. For above-ground attributes, leaf area index (LAI) was measured in 2012, whereas soil coverage ratio was estimated by image processing in 2016. Results showed that [NH4+-N] increased gradually after transplanting and then rapidly decreased from a certain day. This distinct drop in [NH4+-N] informed us the timing at which the rice root system reached the point of porous tubing and thus essentially covered the whole soil volume. The LAI at the dropping point was about 0.43 regardless of the cropping schedules in 2012 experiment. In 2016, the coverage ratio at the N dropping point was within the range of 0.12 to 0.19 for four genotypes having different growth durations. In addition, the coverage ratios at seven weeks after the transplanting showed a good correspondence to LAI across the four genotypes. We therefore conclude that both LAI and coverage ratio may serve as robust indicators for root development and might be useful to estimate the timing when the root system fully cover the soil volume. Results obtained here will also contribute to develop models that can predict not only above-ground canopy development but also associated below-ground processes.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.2
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• pp.65-75
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• 2018

This study analyzes the characteristics of the urban landscape changes as a result of the introduction of private parks among the long-term uncollected urban planning facilities and enables the analysis of the characteristics of the urban landscape changes as a result of the introduction of private parks, and applied to the private park projects. The DSM with its building was established for the quantitative landscape analysis to examine the view ratio using the stacked visible analysis. The analysis showed that Jikdong Park had a high frequency of view from downtown to green due to its location, and that the development project of a private park on park and town boundaries significantly lowered the view ratio. This implies a large degree of damage to the landscape by development projects provided protection of the view as a natural landscape is of value. Chudong Park also saw its view ratio of views from downtown to the hills green area of Chudong Park was much lower than that of Jikdong Park. And it was confirmed that the ratio of view changes due to development projects was small compared to that of Jikdong Park. In other words, although Jikdong Park and Chu-dong Park were developed in a similar scale in terms of the ratio of views, they were subject to significant damage due to their location characteristics. It is also meaningful to note that the degree of change in the landscape resulting from development projects that could not be found in the assessment or review of the existing Landscape Impact. As private parks are introduced in the urban green belt, apartment development is being pushed for at the edge of the green belt. This study is meaningful in that it is derived based on the calculation that the survey results are derived based on the changes in the views on green areas that urban residents may experience as the private park project is carried out, and it should be introduced based on the calculation of the private parks.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.1
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• pp.31-36
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• 1981

This pot experiment was conducted to find out the optimal fertilization ratio of the anions (N : S : P) in various soil conditions. Soil samples were collected from uncultivated mountains and hills where development for grasslands is under consideration. The optimum ratios were computed by the $Hom{\grave{e}}s$ systematic variation technique. The results were summarized as follows : 1. The optimum fertilization ratios of the anions (N : S : P) for the high yields of grass - clover mixed sward at various areas were obtained (Table 5). 2. The grass yields in mixed sward were increased by the increase of specific soil characteristics, CEC, OM, T-N, avail-$P_2O_5$. However. it was not recognizable by the contents of the cations, the base saturation, and the pH. 3. The relatively high yields of clover were positively related to the Ca and Mg contents in soils, and it was a factor of the increased total yields of mixed sward. 4. The relatively high optimum fertilization ratios of S in volcanic ash soil in the Cheju district and P in sediment lithosol in Daegu should be taken into account in determing the fertilization rate for high yield of clover in mixed sward.

• Journal of Navigation and Port Research
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• v.35 no.8
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• pp.625-629
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• 2011

In this study, we analyzed the signal environment of 17 DGNSS stations operated by DGPS Central Office through TEQC quality checking, visibility analysis and site visits. With TEQC, we produced times series of four indices of TEQC quality checking: observation ratio, L1 pseudorange multipath, L2 pseudorange multipath, and the frequency of cycle slip events. From visibility analysis, the directions where missing observations are happening were identified and the result was verified through onsite investigation. Without considering TEQC indices at the six sites(Palmido, Eochungdo, Geomundo, Pyeongchang, Seongju, and Chungju), the average TEQC indices were: 98% observation ratio, 0.19m of L1 pseudorange multipath, 0.71m of L2 pseudorange multipath, and 1.3 cycle slips per 1000 observations. The observation ratios at Palmido and Eochungdo were low. It was found that receiver settings were incorrect so that they could track the P2 signal of GPS satellites with L2C capability. No signal-blocking obstacles were found around the Geomundo station except the lighthouse. Thus, we guess that the poor TEQC indices at the site are believed to be caused by problems in the GPS hardware or cables. The low observation ratio at Pyeongchang is being caused by the surrounding hills blocking the satellite view from the south to the northwest directions. Even though all of four TEQC indices were bad at Seongju and Chungju stations, we found that the signal reception environment at the two sites is in good condition. We think that the quality indices got poor probably because of malfunctioning equipment. So, further investigation is needed for the Seongju and Chungju sites.

• 한국해양학회지
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• v.23 no.3
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• pp.110-122
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• 1988

Between the Clarion and Clipperton fracture zones of the Northeastern Pacific, nodules and crusts were collected from abyssal plain and hills by the Korea Ocean Research and Development Institute in December, 1983 aboard the R/V KANA KEOKI of the Hawaii Institute of Geophysics. Mineralogical and geochemical data of bulk nodules are obtained and compared with analyses of other studies. Mechanisms of nodule formation are discussed based on these data. Generally, the nodules of the KONOD-1 site are composed of todorokite and ${\delta}-MnO_2$. The contents of Mn, Fe, Ni, and Cu of the bulk nodules are variable and the average contents of metals are slightly lower (Mn, 21.40%; Ni, 0.9%; Cu, 0.8%) than those of nodules from other abyssal plains between the Clarion and Clipperton fracture zones. High Mn/Fe (average 3.9; maximum 5.9) and Cu/Ni (average 0.8; maximum 1.0) ratios are similar to the nodules that were formed diagenetically in the northeast Pacific. The chemical characteristics of the KONOD-1 nodules reflect their sedimentary environments; nodules with higher diagenetic signatures occur in areas of thin Quaternary siliceous ooze, and nodules of lower diagenetic influence occur in topographically irregular abyssal hill areas.

• Fire Science and Engineering
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• v.28 no.6
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• pp.13-21
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• 2014

Forest fire has a number of variables and since the effects of wind fields are bigger than any other variables, it is essential to know wind direction and velocity for the forest fire extinguishing techniques and the prediction of fire spread. With regards to the local area that has a high chance of forest fire, the data from meteorological observatory in the area is used for the estimation of wind velocity. It is relatively easy to obtain automatic weather station (AWS) data which are available for the whole nation. There is a chance that the data from the weather station may be different with the actual data at the mountain areas. In this study simply shaped hills (Sae-byeol hill of Jeju Island and port Ma-geum in An-myeon Island in the sea side) were selected as the experimental locations to minimize the distortion of the wind field by the adjacent geographic features. Spot measurements and analysis of computational fluid dynamics (CFD) for the given geographic features were conducted to examine and compare their consistency. As a conclusion It is possible to predict wind patterns in these simple locations.

• Journal of Korean Society of Rural Planning
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• v.6 no.1 s.11
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• pp.19-28
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• 2000

Now in order to overcome the weakest points of the rural areas of the city of Kimje and, transform them into rural cultural villages which have local governing systems suitable to new localization age and activate this plan, we selected Daesan Village as a model village which had shown a lot of potentials in the basic research and studied it dividing it into the former part and the latter part. We studied Daesan village in the former part focusing on state analysis and basic ideas and in the latter part focusing on master plan and detail planning. We can summarize the conclusion like the followings. 1. Daesan Village located 8 kilometer away from the downtown Kimje and the city of Iksan respectably has comparatively good environment of good sunny place as an open field whose surrounding configuration of the ground consists of farming lands and low hills in front and rear. It has 38 farming households in all. 2. Human environment(인문환경); the village road whose width is about 4 meters is forming a flow system forking off into three. There is a route bus which operates three times a day even into the inside of the village. The main sources of revenue are vegetables in facilities, fruits and floriculture. Their average revenue is about 10.5 million won. 3. Here in DaeSan Village a legend dealing with Teasan literally meaning a big mountain consist of th village's tradition and you can see the tombs of a very faithful son and Anwi an army general in the age of the Japanese Invasion of Korea of 1592 to 1598 inside the village. 4. 85 out of the eitire population 141 whose age are over 20 showed very positive attitudes in a questionnaire about, making the village a cultural one and its development. 5. The basic of planned ideas is to increase the revenue of the farming household by making the village a professional farming one which has a state-of the-art production facility and agricultural technique. It is to make the village the one where people can enjoy the sense of the rural life and the farmer can enjoy their lives through consumptive and consistant leisure and resting activities. 6. We are planning to make entrance space, life space, rest and sport space, and cultural space considering the characteristics of the village and the demand of the resident. We are also planning to make tile entire city of Kimje an information transmitting base in short and long term perspectives. 7. DaeSan Village was planned as a place where tradition and the future exist together. On the basis of this concept we planned future programs for Daesan Village and in the latter part of the study master plans and detail plans will be continued.the regional agricultural condition. The development permissions were only during the period of restricted to use ($1979.12{\sim}1993.11$). We propose that the authority of development permission should be given to the local autonomy government, because the local government has the knowledge of its individual agricultural conditions.

• Korean Journal of Medicinal Crop Science
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• v.11 no.2
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• pp.109-114
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• 2003

To determine the optimum N rate m Jeju island for utricle and root production of Achyranthes japonica Nakai, a medicinal plant, the plants were grown at two plant densities $(50\;and\;100\;hills/m^2$, two plants per hill; mall plots) at six N application rates (0, 6, 12, 18, 24, and 30 kg/10a; split plots) in 2001. There was no significant interaction between plant density and N application rate for all measured agronomic characters. Main root length and roots per hill were 5 and 52% greater, respectively, but N content of stover was lower under lower plant density compared to higher plant density. The other characters were not affected by plant density. N application rate did not significantly affect mall stem diameter, spikes per hill, spike length, utricles per spike, mall root length and diameter, and utricle N content. As N rate increased from 0 to 30 kg/10a, SPAD values and stover N content increased linearly from 35.0 to 40.5 and 1.09 to 1.38%, respectively, and plant height, branches per hill, stover, utricle and root dry matter yields, roots per hill, and top N yield increased quadratically. Spikes per hill were increased in a cubic manner with increased N application rates. N application rate for the maximum dry matter yield of utricle and root in A. japonica was estimated to be 21 kg N/10a.

• Journal of the Korean association of regional geographers
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• v.2 no.1
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• pp.39-49
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• 1996

There is a limestone basin surrounded by the mountains consisted of Paleozoic sedimentary and metamorphic rocks in the Masung, Munkyung city, Kyungsangpook do. The purpose of this paper is to elucidate the geomorphic processes of the gentle hillslopes in the marginal piedmont of Masung basin. To do so, I analyzed deposits over hillslopes and the relation ship between the distance from the divide and the height(above sea level) at the longitudinal profile of the hillslope, and considered interrelation between the distributions of the gentle hillslopes(less than 230m) and lithology. Geomorphic processes of Masung basin are as follow: (1) The depth of deposits over hillslope increases toward downstream of the hillslope. Most gravels within deposits, whose lithology is limestone, are those eroded at the boundary(overthrust fault zone) between the back-mountain and the hillslope. Deposits at the outward margin of hillslope is well sorted. and moderately imbricated. (2) Hillslope at the margin of the basin(160-230m asl) is formed by the action of 'the flow with channel'. At the boundary between the soft rock(limestone; basin floor) and hard rock(sedimentary and metamorphic rock; back-mountain), the relatively weak limestone is eroded to fresh bedrock by the subsequent action of the overland flow, and therefore discontinuity in slope appeared. (3) After hills lopes were formed, sediments(boulders and fine material) produced during dissection in back-mountain buried deposits over hillslope. In conclusion, geomorphic processes of Masung basin is 'differential erosion due to differentiation of lithological hardness' having suggested as geomorphic processes of granitic basin. However it is not 'removal of weathering material due to sheetflow' but 'erosion due to the overland flow with channel'.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.1
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• pp.21-35
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• 2009

KOMPSAT-2 is the seventh high-resolution image satellite in the world that provides both 1m-grade panchromatic images of the GSD and 4m-grade multispectral images of the GSD. It's anticipated to be used across many different areas including mapping, territory monitoring and environmental watch. However, due to the complexity and security concern involved with the use of the MSC, the use of KOMPSAT-2 images are limited in terms of geometric images, such as satellite orbits and detailed mapping information. Therefore, this study aims to produce DEM and orthoimage by using the stereo images of KOMPSAT-2, and to explore the applicability of geo-spatial information with KOMPSAT -2. Orientation interpretations were essential for the production of DEM and orthoimage using KOMPSAT-2 images. In the study, they are performed by utilizing both RPC and GCP. In this study, the orientation interpretations are followed by the generation of DEM and orthoimage, and the analysis of their accuracy based on a 1:5,000 digital map. The accuracy analysis of DEM is performed and the results indicate that their altitudes are, in general, higher than those obtained from the digital map. The altitude discrepancies on plains, hills and mountains are calculated as 1.8m, 7.2m, and 11.9m, respectively. In this study, the mean differences between horizontal position between the orthoimage data and the digital map data are found to be ${\pm}3.081m$, which is in the range of ${\pm}3.5m$, within the permitted limit of a 1:5,000 digital map. KOMPSAT-2 images are used to produce DEM and orthoimage in this research. The results suggest that DEM can be adequately used to produce digital maps under 1:5,000 scale.