• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.17 no.2
• /
• pp.245-261
• /
• 2019

Radioactive contaminant from a nuclear facility moves to the ecosystem by run-off or groundwater flow. Among the two mechanisms, contaminant plume through a river can be easily detected through a surface water monitoring system, but radioactive contaminant transport in groundwater is difficult to monitor because of lack of information on flow path. To understand the contaminant flow in groundwater, understanding of the geo-environment is needed. We suggest a method to decide on monitoring location and points around an imaginary nuclear facility by using the results of site characterization in the study area. To decide the location of a monitoring well, groundwater flow modeling around the study area was conducted. The results show that, taking account of groundwater flow direction, the monitoring well should be located at the downstream area. Also, monitoring sections in the monitoring well were selected, points at which groundwater moves fast through the flow path. The method suggested in the study will be widely used to detect potential groundwater contamination in the field of oil storage caverns, pollution by agricultural use, as well as nuclear use facilities including nuclear power plants.

• 한국사회정책
• /
• v.24 no.4
• /
• pp.185-222
• /
• 2017

The purpose of this study is to investigate the effect of labor market policy on fiscal soundness of welfare state. The analysis was carried out using cross-sectional panel data regression analysis, stepwise mediating effect analysis and system GMM designed by Baron and Kenny(1986) based on the data from 1985 to 2015 for 20 OECD countries. In setting up the analysis model, this study considers the interaction effect between active and passive labor market policies as well as the time sequence of the outcomes which have been overlooked in the previous studies. The result shows that labor market policies have significant impacts on the fiscal condition of welfare states, which is measured as the levels of national debt in this study. Especially the expenditure on active labor market programs has a positive effect on improving the fiscal soundness of welfare states by promoting the employment rate. In contrast, passive labor market programs expenditure is negatively associated with employment rate growth and it exacerbates the burden of national debt in the short-term. However, when active labor market programs and passive labor market programs are combined, the negative impacts by passive pabor market policies on the fiscal soundness of welfare states are off-set. Therefore this study addresses that although the expansion of the labor market policies can be inimical to the fiscal soundness of welfare states in the short-term, in the long run, they can have effective roles in securing and promoting the fiscal soundness of the welfare states by promoting the employment rate.

• (The)Study of the Eastern Classic
• /
• no.37
• /
• pp.345-375
• /
• 2009

In relation to body conception, the introduction of western medicine to Joseon Korea started off some points in disputes: the one was whether the western anatomy was positive or not, the other was whether the cognition was ruled by heart or brain. In the long run of these disputes, that who had clarified the change of body conception was Choi Han Kee. His new conception of body was characterized as follow: on the one hand, it emphasized the mechanical conception of body; on the other hand, it emphasized the cognitive ability of body. But that his conception of body had obscure points: that is, its mechanical conception was intervened by chi(神氣), and his doctrine of cognition searched for the origin of cognition in balance of chi of the body. He had set up this conception of body by the combination of western medicine and chi, but the combination did not seem to be perfect. This point had appeared again in his conception of physics that he thought the basis of medicine. He had pursed the combination of chemical element and chi, but it could not be accomplished successfully unless he had abandoned the organicist conception of chi. In conclusion, his new conception of body was not free from the suspicion of a incomplete tentative construction.

• Journal of the Korean Geotechnical Society
• /
• v.22 no.5
• /
• pp.83-91
• /
• 2006

Recently, the intensive rainstorm possibly induced by global warming plays a key role on the instability of railway adjacent slopes. The instability of slopes results as covering and loss of railway lines induced by slided soil mass. According to the site investigation on the failed slopes triggered by rainfall, low types of slope failure were observed: shallow, intermediate, gully erosion, and soil-rock interface failures. The observation reveals the different characteristics of slope failure depending on the thickness of soil layer, morphological features of slope, etc. Based upon the observations, flume tests were conducted to analyze the sliding mechanism of each failure. The variables of flume test are soil layer thickness, rainfall intensity, and morphology of slope under the constant condition of the percentage of fine, initial soil moisture content, slope angle and compaction energy. Test results show that shallow failure was mostly observed from the surface of the slope and caused by the soil erosion; in addition, compared to the other types of failure, the occurrence of initial erosion is late, however, the development of erosion is fast. In gully erosion failure, the collected water from the water catchment area helps erosion of the upper soil layer and transfer of residual corestone, which impedes the erosion process once the upper soil layers are eroded and corestone are exposed. The soil-rock interface failure shows the most fast initial erosion process among the failure types. Interestingly, the common feature observed from the different types of failure was the occurrence of the initial deformation near the toe of slopes which implies the existence of surbsurface flow along the downslope direction.

• Journal of Hydrogen and New Energy
• /
• v.33 no.1
• /
• pp.95-104
• /
• 2022

Micro hydropower is a readily available renewable energy source that can be harvested utilizing hydrokinetic turbines from shallow water canals, irrigation and industrial channel flows, and run-off river stream flows. These sources generally have low head (<1 m) and low velocity which makes it difficult to harvest energy using conventional turbines. A horizontal-axis screw turbine was designed and numerically tested to extract power from such low-head water sources. The 3-bladed screw-type turbine is placed horizontally perpendicular to the incoming flow, partially submerged in a narrow water channel at no-head condition. The turbine hydraulic performances were studied using Computational Fluid Dynamics models. Turbine design parameters such as the shroud diameter, the hub-to-shroud ratios, and the submerged depths were obtained through a steady-state parametric study. The resulting turbine configuration was then tested by solving the unsteady multiphase free-surface equations mimicking an actual open channel flow scenario. The turbine performance in the shallow channel were studied for various Tip Speed Ratios (TSR). The highest power coefficient was obtained at a TSR of 0.3. The turbine was then scaled-up to test its performance on a real site condition at a head of 0.3 m. The highest power coefficient obtained was 0.18. Several losses were observed in the 3-bladed turbine design and to minimize losses, the number of blades were increased to five. The power coefficient improved by 236% for a 5-bladed screw turbine. The fluid losses were minimized by increasing the blade surface area submerged in water. The turbine performance was increased by 74.4% after dipping the turbine to a bottom wall clearance of 30 cm from 60 cm. The final output of the novel horizontal-axis screw turbine showed a 2.83 kW power output at a power coefficient of 0.63. The turbine is expected to produce 18,744 kWh/year of electricity. The design feasibility test of the turbine showed promising results to harvest energy from small hydropower sources.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.41 no.3
• /
• pp.56-71
• /
• 2013

This study was carried out to investigate the construction background of multi-functional vacant grounds in the rear gardens of Kyeongbok Palace and Kyeongun Palace, by understanding the building history of multi-functional vacant ground during the Joseon Dynasty with a special reference to the places formed in the period of King Kojong. The multi-functional vacant grounds in the Palace were the important element from the political aspect of Joseon Dynasty, and became an infrastructure of a state - run organization. The vacant space between Kwangyeonlu(廣延樓) and Haeonjeong, the whole region of Yeolmujeong(閱武亭), Seochongdae(瑞蔥臺), and Chundangdae(春塘臺) were investigated as the multi-functional places, where the events were held for the royal family in the Changdeok Palace after the establishment of the Joseon Dynasty. Various events such as the archery competition, official examination and military training were held at the places. After the inauguration of King Kojong, Kyeongmudae(京武臺) was made in the process of the reconstruction of the Kyeongbok Palace. The Kyeonghee Palace was used as the off-palace rear garden after the year that King Kojong returned to the Kyeongun Palace. The characteristics of two spaces were to apply the space organization of the Changdeok Palace into the rear garden outside of Sinmumun(神武門), Kyeongmudae at Kyeongbok Palace and the pedestrian overpass was established to connect the spaces efficiently in Kyeonghee Palace. Especially, the multi-functional vacant ground in the rear garden during the period of King Kojong functioned as the place to show off the internal and external independence of a nation and to show the authority and dignity of King at the point of time that accelerated the plundering Joseon Dynasty by Japanese imperialism powers, beyond the meaning of national event space that had existed before, such as official examination or archery test. In addition, the fact that the multi-functional vacant ground used as training place for military exercise where many people were mobilized was considered to reflect the contemporary situation.

• Journal of Animal Environmental Science
• /
• v.11 no.2
• /
• pp.117-124
• /
• 2005

Livestock manure has been utilized as fertilizer, and trying to make resources natural circulation of organic material. This experiment was conducted to investigate the effect of application level of swine slurry on agronomic characteristics and yield of silage corn and $NO_3-N$ content of soil for three years in the experimental field of Grassland and Forage Crops Division, National Livestock Research Institute. Summary of the results were as follows. The experiment was conducted according to a randomized complete block design. Six treatments were non fertilizer(NF), chemical fertilizer(CF), $100\%$ swine slurry(SS100), $150\%$ swine slurry(SS150), $200\%$ swine slurry(SS200) and mixture fertilizer(MF, $100\%$ swine slurry + $50\%$ chemical fertilizer) with three replications. The application level of swine slurry(SS) $100\%$ was highest in Brix as $8.6^{\circ}$ and stay green was as swine slurry application increased. Deficiency of plant, plant height, ear height and lodging were increased in above $100\%$ swine slurry application level. Dry matter yield was decreased in SS 100 but increased in SS 150 and SS 200. Significant effect was observed for all treatments. The content of $NO_3-N$ in infiltration water was high in above swine slurry nitrogen $150\%$ but that content in run off water was very small. Conclusively, application to swine slurry below $150\%$ would be recommended to produce higher yield and to conserve environment in corn field.

• Strategy21
• /
• s.32
• /
• pp.123-159
• /
• 2013

The purpose of this research paper is to re-valuate the factors that affected the Royal Navy's rearmament and preparation for war by conducting analysis on the discussion held in the Britain on the strategic priorities and Navy's coping measures adopted during the interwar period. After the end of the WWI, each of the military arms of the Britain faced significant difficulty in securing budget and increasing their military power all throughout the interwar period, and the Navy was not an exception. The WWII that got started on September 1939 was the turning point in which this difficulty led to full-fledged crisis. Immensely many criticisms followed after the war and problems were identified when it comes to the Royal Navy's performance during the war. This type of effort to identify problem led to the attempt to analyze whether Royal Navy's preparation for war and rearmament policy during interwar period were adequate, and to identify the root causes of failure. Existing studies sought to find the root cause of failed rearmament from external factors such as the deterioration of the Britain itself or pressure from the Treasury Department to cut the budget for national defense, or sought to detect problems from the development of wrong strategies by the Navy. However, Royal Navy's failed preparation for the war during interwar period is not the result of one or two separate factors. Instead, it resulted due to the diverse factors and situations that the Britain was facing at the time, and due to intricate and complex interaction of these factors. Meanwhile, this research paper focused on the context characterized by 'strategic selection and setting up of priorities' among the various factors to conduct analysis on the Navy's rearmament by linking it with the discussion held at the time on setting up strategic priorities, and sought to demonstrate that the Navy Department's inadequate counter-measures developed during this process waned Royal Navy's position. After the end of WWI, each of the military arms continued to compete for the limited resources and budget all throughout the interwar period, and this type of competition amidst the situation in which the economic situation of Britain was still unstable, made prioritization when it comes to the allocation of resources and setting up of the priorities when it comes to the military power build-up, inevitable. Amidst this situation, the RAF was able to secure resources first and foremost, encouraged by the conviction of some politicians who were affected by the 'theory of aerial threat' and who believed that curtailing potential attack with the Air Force would be means to secure national security at comparatively lower cost. In response, Navy successfully defended the need for the existence of Navy despite the advancement of the aerial power, by emphasizing that the Britain's livelihood depends on trade and on the maintenance of maritime traffic. Despite this counter-measuring logic, however, Navy's role was still limited to the defense of overseas territory and to the fleet run-off instead of sea traffic route production when it comes to the specific power build-up plan, and did not understand the situation in which financial and economic factors gained greater importance when it comes to the setting up of strategic priorities. As a result, Navy's plan to build its powers was met with continual resistance of the Treasury Department, and lost the opportunity to re-gain the status of 'senior service' that it had enjoyed in the past during the competition for strategic prioritization. Given that the strategic and economic situation that Korea faces today is not very different from that of the Britain during the interwar period, our Navy too should leverage the lessons learned from the Royal Navy to make the effort to secure viable position when it comes to the setting of priorities in case of national defense strategy by presenting the basis on why maritime coping should be prioritized among the numerous other threats, and by developing the measures for securing the powers needed effectively amidst the limited resources.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.6
• /
• pp.1203-1210
• /
• 2012

As the area of upland crops increase, it is become more important for farmers to understand status of soil water at their own fields due to key role of proper irrigation. In order to estimate daily water balance and soil water content with simple weather data and irrigation records, we have developed the model for estimating water balance and soil water content, called AFKAE0.5, and verified its simulated results comparing with daily change of soil water content observed by soil profile moisture sensors. AFKAE0.5 has two hypothesis before establishing its system. The first is the soil in the model has 300 mm in depth with soil texture. And the second is to simplify water movement between the subjected soil and beneath soil dividing 3 categories which is defined by soil water potential. AFKAE0.5 characterized with determining the amount of upward and downward water between the subjected soil and beneath soil. As a result of simulation of AFKAE0.5 at Gongju region with red pepper cultivation in 2005, the water balance with input minus output is recorded as - 88 mm. the amount of input water as precipitation, irrigation, and upward water is annually 1,043, 0, and 207 mm, on the other, output as evapotranspiration, run-off, and percolation is 831, 309, and 161 mm, respectively.

• Korean Journal of Environmental Agriculture
• /
• v.12 no.2
• /
• pp.129-143
• /
• 1993

The objective of this study is to understand the status of the water pollution in rural areas and to furnish a basic material for the management of the water pollution in rural areas. For this purpose, the Bokha river basin, Ichon-Gun, Kyungki-Do considering as a typical agricultural area was selected as a representative experimental watershed. The characteristics of water pollution in streams of the Bokha river basin was revealed by investigating and analyzing data collected for the source of pollution, water qualities in reaches of the stream, the degree of contribution to the river contamination by pollution mass produced from each source, and the status of the self-purification at the main stream. The most important source of the water pollution in investigated watershed was livestock, and the next important one were in the order of population, land use, and industry. The water quality of the Bokha river was relatively favorable judging from the BOD and COD concentration, however since the concentration of T-N and T-P showed significantly large values, it was concluded that the river was seriously contaminated by the nutrient material. The main cause of the river contamination was proved due to livestock waste. For the T-N, both land use and livestock were much more contributied to the pollution than any other source, which characterized the typical water pollution of rural areas. Run-off ratios for the Bokha river tributaries to the main stream were changed according to the similar trend to the variation of discharges in the branch streams. For the value of the self-purification constant at the main stream, it showed smaller value in the downstream reach than the middle-stream and upstream reaches, where could possibly have smaller reoxidation action due to slower velocity and deeper water depth.