• Journal of Korean Society of Transportation
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• v.19 no.4
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• pp.35-47
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• 2001

Traffic represents one of the largest sources of primary air pollutants in urban area. As a consequence. numerous abatement strategies are being pursued to decrease the ambient concentration of pollutants. A characteristic of most of the these strategies is a requirement for accurate data on both the quantity and spatial distribution of emissions to air in the form of an atmospheric emission inventory database. In the case of traffic pollution, such an inventory must be compiled using activity statistics and emission factors for vehicle types. The majority of inventories are compiled using passive data from either surveys or transportation models and by their very nature tend to be out-of-date by the time they are compiled. The study of current trends are towards integrating urban traffic control systems and assessments of the environmental effects of motor vehicles. In this study, a methodology of motor vehicle emission calculation by using real-time traffic data was studied. A methodology for estimating emissions of CO at a test area in Seoul. Traffic data, which are required on a street-by-street basis, is obtained from induction loops of traffic control system. It was calculated speed-related mass of CO emission from traffic tail pipe of data from traffic system, and parameters are considered, volume, composition, average velocity, link length. And, the result was compared with that of a method of emission calculation by VKT(Vehicle Kilometer Travelled) of vehicles of category.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.1
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• pp.93-103
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• 1992

Experiments were conducted in the research field of the Wheat and Barley Research Institute with three barley cultivars, Olbori, Kangbori and Suwon 18, which showed different growth characteristics. The highest rates of daily dry matter accumulation in grains were 1.03 1.94 mg / grain / day in early and optimum sowings and 0.88 1.88 mg / grain / day in late sowings, which occurred around 20～30 days after heading in early and optimum sowings and 15～20 days after heading in late sowings. Grains reached their maximum weight by 40 days after heading in early and optimum sowings and 35 days after heading in late sowings. Total sugar content in grains followed a pattern of linear increase immediately after heading, but it started to decrease around 20 days after heading. On the other hand, starch content continued to increase until maturity. The contents of both components were high in the order of ＆apos;Olbori＆apos; ＆gt; ＆apos;Kangbori＆apos; ＆gt; ＆apos;Suwon 18＆apos;, but they did not respond in a regular pattern to different sowings. 1,000 grain weight showed highly significant positive correlation(r=0.767$^{**}$) with the duration of grain growth, but it had negative correlations with the average (r=-0.548$^{**}$) or the sum (r=-0.595$^{**}$) of post-anthesis daily mean temperature.ature.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.4
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• pp.252-257
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• 1991

In a two-year's field experiment, the effectiveness of magnesium-and boron-enriched complex fertilizer (CF, N-P$_2$O$_{5}$-K$_2$O-MgO-B$_2$O$_3$: 14-10-12-3-0.2) on the maintenance and management of hilly pasture was studied. The effects of CF and some straight fertilizers (SF) on forage yields, yield components, and chemical compositions were compared in a mixed grass-clover (orchardgrass, tall fescue, kentucky bluegrass, and ladino clover) and a pure grass (orchardgrass) swards. The results are summarized as follows: 1. Considerably higher average dry matter yields were obtained in the CF plots than in the SF plots. In the mixed sward, the yields of whole mixed forages were inclosed by 10.8-14.5%, grasses by 11%, and legume by 21.5-31.0% by the use of the CF over the use of SF. In the pure grass sward, the yield of grasses was increased by 7.0-21.8%. 2. The rates of yield increase due to the application of CF were dependent on such factors as types of sward (pure or mixed), application rates of NPK, and forage species. The increase of forage yields due to the CF was greater at the normal rate of NPK application than at lower application rate, and in legume forage than in grass forage. 3. The crude fiber, crude fat and NFE contents of forages were not significantly changed by different treatments. However, the forage of CF plot at the normal application rate of NPK contained relatively higher amount of crude protein and crude fat compared with the forages of other plots. 4. There were no significant differences in the contents of mineral nutrients in forages among the different treatments. In spite of the application of Mg-enriched CF, the contents of Mg in soils and forages were below the optimum level.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.233-238
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• 2006

The experimental work was conducted to determine the growth characteristics, yield and feed value of sorghum-sudangrass hybrid and $NO_{3^-}N$ leaching by application of various types of livestock manure (LM) at National Livestock Research Institute, Suwon, for 3years (2003-3005). The growth characteristics in chemical fertilizer (CF) was better than others in general. The growth characteristic of sorghum-sudangrass hybrid by the various type of LM was good in order of composted swine manure (CSM) > liquid swine manure (LSM) > composted cattle manure (CSM), whereas the growth characteristics by application level of LM was good in order of LM 100%+CF 25%>LM 75%+CF 25%>LM 100%. Dry matter(DM) yield in LSM and CSM increased by 23% and 18% respectively while DM yield in CCM decreased 24% as compared to CF. Moreover total digestible nutrients (TDN) in LSM and CSM increased by 24% and 18% respectively while TDN in CCM decreased 12% as compared to CF. Crude protein and relative feed value in LM decreased compared to those in CF. $NO_{3^-}N$ leaching by application level of LM showed that there was an increase in order of LM 100%+ CF 25%>LM 75%+CF 25%>LM 100%. Also the high concentration of $NO_{3^-}N$ occurred shortly after application of LM.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.1
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• pp.62-72
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• 1985

In order to find out the effects of seeding time on growth, dry matter production and nutritive content of Pioneer 931, Pioneer 988 and Piper, this study was carried out on the experimental field of Livestock Experiment Station in 1981-83. Seeding time were 7 with 14-day interval from April 16 to July 9. The results are summarized as follows: 1. It tool about 12 to 13 days from seeding to emergence in case of Mid-April seeding and 7 to 8 days in Late-June. Earlier seeding, more longer growth period from emergence to heading they required. 2. Plant height of Pioneer 931 seeded lately was longer than 4.5 meters in primary growth and Sudangrass was about 2.0 to 2.5 meters. Leaf area was the greatest in Mid-August by early seeding but it was increased until Early-October by late seeding. 3. Sorghum gas brought the highest yield in dry mater and Sudangrass the lowest. In general dry matter yield reduced gradually in response to later seeding but Pioneer 931 has brought more than 10 tons per hecter until Late-June. 4. Relative Growth Rate, Leaf Area Ratio and Leaf Weight of all varieties decreased in accordance with growth development. 5. Crude protein content of leaf was higher than stem and the younger the plants, the more protein they contain. Nitrogen Free Extract was just opposite to crude protein.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.3
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• pp.183-188
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• 2007

This study was conducted to determine the effects of seeding date on agronomic characteristics, productivity and feed value of Italian ryegrass, barley and rye during cropping after rice in Suwon, middle region of Korea, during 2004 and 2005. In general, early seeding (26 September) showed longer plant length and branch numbers per square meter than late sowing (11 October). Italian ryegrass had more early seeding effect than barley and rye. The yield of each plant was affected by sowing date in all experiments: the earlier seeding had higher yields than late seeding. In case of Italian ryegrass and barley as late-heading varieties showed more early seeding effect than rye. On the other hand, feed value tended to respond differently to yields. The feed value of each plant were based on liquid swine manure (12%) > composted cattle manure (7%) > composted swine manure (2%). The present results highlight the earlier planting obtained higher yield compared to those planted conventionally.

• Applied Biological Chemistry
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• v.15 no.1
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• pp.85-92
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• 1972

The field experiment was performed to investigate the effects of various kinds of phosphorus fertilizers such as double superphosphate, fused magnesium phosphate and Simagcarin (both the Kyun-gi Chemical Co, products) on the physiological roles in development of root system, growth and yield compositions of rice plant. Radioactive phosphoric acid $(H_3\;^{32}PO_4)$ was applied to measure the root activity. 1. The number of total tillers was significantly increased in double superphosphate plots, but the rate of fruitful tillers was more numerous in the fused magnesium phosphate and the Simagcarin plots than that of the other plots. 2. The grain yield was much more obtained in the fused magnesium phosphate and Simagcarin plots (no significant difference were found between both of plots) than the double superphosphate and control plots. It seemed due to the increasing of seedbearing rate and number of fruitful tillers. 3. In double superphosphate plots, root system was mostly developed near topsoil areas, but fused magnesium phosphate and the Simagcarin plots, root system was uniformly distributed from topsoil to subsoil areas. 4. As the results of those experiments, fused magnesium phosphate and Simagcarin was demonstrated to be soil amendmentical materials rather than the phosphorus fertilizers, especially in low productive paddy soils which lack the special mineral nutritions.

• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.522-529
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• 2013

Climate change will affect the physiological traits and growth of forest trees. This study was conducted to investigate the effects of an experimental warming on growth and physiological characteristics of Pinus densiflora S. et Z. seedlings. One-year-old P. densiflora seedlings were planted in control and warmed plots in April 2010. The air temperature of warmed plots was increased by $3^{\circ}C$ using infrared lamps from November 2010. We measured shoot height, root collar diameter, above and below ground biomass, chlorophyll contents and leaf nitrogen concentration from March 2011 to March 2013. Seedling height and root collar diameter showed no significant difference between warmed and control plots except for root collar diameter measured in June 2012. Seedling leaf biomass was lower in the warmed ($23.94{\pm}2.10g$) than in the control ($26.08{\pm}1.72g$) plots in 2013. Shoot to root ratio (S/R ratio) was lower in the warmed ($1.09{\pm}0.07$) than in the control ($1.31{\pm}0.10$) plots in 2013. Leaf nitrogen concentrations and chlorophyll contents were not significantly different between warmed and control plots except for leaf nitrogen concentration in 2011. Leaf C/N ratio was increased in 2012 under the warming treatment. Low growth and S/R ratio in warmed plots might be related to the higher temperature and water stress. In the future, the below-ground carbon allocation of P. densiflora might be increased by global warming due to temperature and water stress.

• Journal of Korean Society of Forest Science
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• v.105 no.3
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• pp.275-283
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• 2016

The objective of this study was to examine carbon dynamics with biomass, soil $CO_2$ efflux, litter and root decomposition after tree density control in young Pinus densiflora stands. The stands were established with 50% thinning, clear-cut, and control stands with three pseudo-replicated plots and a bare soil plot in 8-year-old Pinus densiflora nursery field. Monthly measurements were conducted from March 2012 to February 2014 and aboveground biomass and coarse-roots were estimated by derived allometric equations. Average diameter growth at root collar in control and thinned was 0.89 cm and 1.48 cm per year, respectively, and the diameter growth of control stand was significantly higher than that of thinned stands (p<0.05). Total biomass was estimated to 5.17, $4.85kg\;C\;m^{-2}$ per year in control and thinned, respectively. Annual soil $CO_2$ efflux in control, thinned, clear cut, and bare soil was 3.71, 3.90, 4.17, $4.56kg\;CO_2\;m^{-2}\;yr^{-1}$, respectively and removing trees significantly increased soil $CO_2$ efflux (p<0.05). Net Ecosystem Production (NEP) was 1.57, 1.36, -0.67, $-1.25kg\;C\;m^{-2}\;yr^{-1}$ in control, thinned, clear cut and bare soil in the young Pinus densiflora stands. NEP was significantly decreased by removing trees. Thinning increased diameter at root collar and carbon of individual tree and recovered 86% of carbon removed by thinning after one-year. In addition, soil $CO_2$ efflux increased and NEP increased by thinning. Results of this study, tree density control such as thinning increased the carbon storage and growth of the young Pinus densiflora stands.

• The Journal of Engineering Geology
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• v.28 no.1
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• pp.101-115
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• 2018

This study was carried out to evaluate the effects of various filter conditions on unconfined aquifer (alluvial aquifer). We made model test device which has filter layer, pumping well and observation well which consist of sand layer and gravel layer to test. Step drawdown test and long term pumping tests were carried out using the device. The permeability characteristics of each test group were confirmed and the optimal yield was calculated. As a result of comparing the optimal yield of double filter and single filter in sand, dual-filter SD-300 was valued at 216.8 % higher final optimal yield than single-filter SS-300. Comparing the dual filter SD-300 and the single filter SS-100 with a thin filter layer, dual-filter SD-300 was valued at 709.2% higher final optimal yield than single-filter SS-300. As a result of analysis of optimal yield change over time, It was confirmed that the ratio of optimal yield of single filter and dual filter increase over time. In order to evaluate the long-term change in water intake efficiency, we considered the point at which the initial optimal yield was reduced by 50%. The dual filter SD-300 is about 351.1% higher than SS-300, which is the same thickness filter, and about 579.0% higher than SS-100. From these results, Assuming that the point at which the initial quantity of water intake is reduced to 50% is the well life, double filters are expected to increase their lifespan by about 3.5 times over single filters of the same thickness and by about 5.8 times over typical single filter. These results can be used to design wells to river bank filtration or filtered seawater. In addition, it is possible to clarify the effect of the double filter through the comparison with the future field test results.