• Economic and Environmental Geology
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• v.56 no.3
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• pp.311-330
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• 2023

Development of Carbon Capture and Storage (CCS) technique is becoming increasingly important as a method to mitigate the strengthening effects of global warming, generated from the unprecedented increase in released anthropogenic CO₂. In the recent years, the characteristics of basaltic rocks (i.e., large volume, high reactivity and surplus of cation components) have been recognized to be potentially favorable in facilitation of CCS; based on this, research on utilization of basaltic formations for underground CO₂ storage is currently ongoing in various fields. This study investigated the feasibility of underground storage of CO₂ in basalt, based on the examination of the CO₂ storage mechanisms in subsurface, assessment of basalt characteristics, and review of the global research on basaltic CO₂ storage. The global research examined were classified into experimental/modeling/field demonstration, based on the methods utilized. Experimental conditions used in research demonstrated temperatures ranging from 20 to 250 ℃, pressure ranging from 0.1 to 30 MPa, and the rock-fluid reaction time ranging from several hours to four years. Modeling research on basalt involved construction of models similar to the potential storage sites, with examination of changes in fluid dynamics and geochemical factors before and after CO₂-fluid injection. The investigation demonstrated that basalt has large potential for CO₂ storage, along with capacity for rapid mineralization reactions; these factors lessens the environmental constraints (i.e., temperature, pressure, and geological structures) generally required for CO₂ storage. The success of major field demonstration projects, the CarbFix project and the Wallula project, indicate that basalt is promising geological formation to facilitate CCS. However, usage of basalt as storage formation requires additional conditions which must be carefully considered - mineralization mechanism can vary significantly depending on factors such as the basalt composition and injection zone properties: for instance, precipitation of carbonate and silicate minerals can reduce the injectivity into the formation. In addition, there is a risk of polluting the subsurface environment due to the combination of pressure increase and induced rock-CO₂-fluid reactions upon injection. As dissolution of CO₂ into fluids is required prior to injection, monitoring techniques different from conventional methods are needed. Hence, in order to facilitate efficient and stable underground storage of CO₂ in basalt, it is necessary to select a suitable storage formation, accumulate various database of the field, and conduct systematic research utilizing experiments/modeling/field studies to develop comprehensive understanding of the potential storage site.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.41 no.4
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• pp.8-20
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• 2023

Although the landscape architectural facilities need to be repaired according to historical and authentic techniques, the repair criteria of the standard specification for repairing cultural heritages still remain at a theoretical level, and there are little research analyzing detailed techniques from specific cases. This study discussed the repair techniques based on historical facts, around terraced flower beds, ponds, waterways and pavement in the government-managed spaces in the Joseon Dynasty. It analyzed the materials and finish of stone wall elements, the structural reinforcement and backfill materials, and topsoil surface protection measures, and drew out stones for foundation reinforcement, plastering material for agglutination, and stone processing techniques for the terraced flower beds. It examined the materials and structures of the rock revetment, foundation reinforcement and waterproofing techniques and drew out the outstanding characteristics of the foundation work, the recycle of used elements and the management of water quality, for the ponds. It primarily investigated the materials, foundation reinforcement and waterproofing techniques and discovered the repair techniques such as cover stone finishing methods, foundation and backfill materials, and flow reduction methods, for the waterways. Finally, it provided actual cases of the foundation composition, auxiliary materials and tools, and the use of cyperaceae and highlighted the existence of professional craftsmen called Bangjeonjang(方磚匠), for the pavement. This study is expected to be a staring point for discovering the repair techniques for landscape architectural facilities and used as basic data for revising specifications in the future.

• Tunnel and Underground Space
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• v.34 no.4
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• pp.374-392
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• 2024

In order to successfully select a site for deep geological disposal of high-level radioactive waste, it is important to perform the stepwise approach along with the systematic selection and survey of evaluation parameters of geological environmental characteristics suitable for the domestic geological environment. In this study, we evaluated the characteristics of hydraulic conductivity, which is considered the most important evaluation parameter in the field of hydrogeology, targeting a deep-depth rock aquifer where actual disposal facilities are expected to be located. In particular, for the first time in Korea, we obtained in-situ pressure-flow data by directly conducting hydraulic tests in boreholes at depths ranging from 500 m to 750 m in various rock types distributed in Korea (granite/volcanic rock/gneiss/mudstone). And we derived hydraulic conductivity values by rock types and depth using verified analytical methods. For this purpose, precision hydraulic testing equipment developed in-house through this study was used, and detailed investigation procedures based on standard test methods were applied to field tests. As a result of the analysis, the average hydraulic conductivity value was found to be in the range of 10^-9 m/s in all granite/volcanic rock/gneiss areas. In the mudstone area, an average hydraulic conductivity value of 10^-11 m/s was derived, which was about 100 times (2 orders of magnitude) lower than that of the fractured rock aquifers. Moreover, permeability tended to slightly decrease with depth in fractured rock aquifers (granite and volcanic rock areas) containing many rock fractures. The gneiss area tended to have large local differences in permeability according to the composition of the stratum and the development of fracture zones rather than depth. In mudstone areas with weak fracture development, there was no significant variation in rock permeability according to depth. The hydraulic conductivity results by various rock types and depth presented in this study are expected to be utilized in building a foundational database for the site selection, design, and construction of disposal facilities in Korea.

• Journal of Intelligence and Information Systems
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• v.16 no.3
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• pp.77-97
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• 2010

Market timing is an investment strategy which is used for obtaining excessive return from financial market. In general, detection of market timing means determining when to buy and sell to get excess return from trading. In many market timing systems, trading rules have been used as an engine to generate signals for trade. On the other hand, some researchers proposed the rough set analysis as a proper tool for market timing because it does not generate a signal for trade when the pattern of the market is uncertain by using the control function. The data for the rough set analysis should be discretized of numeric value because the rough set only accepts categorical data for analysis. Discretization searches for proper "cuts" for numeric data that determine intervals. All values that lie within each interval are transformed into same value. In general, there are four methods for data discretization in rough set analysis including equal frequency scaling, expert's knowledge-based discretization, minimum entropy scaling, and na$\ddot{i}$ve and Boolean reasoning-based discretization. Equal frequency scaling fixes a number of intervals and examines the histogram of each variable, then determines cuts so that approximately the same number of samples fall into each of the intervals. Expert's knowledge-based discretization determines cuts according to knowledge of domain experts through literature review or interview with experts. Minimum entropy scaling implements the algorithm based on recursively partitioning the value set of each variable so that a local measure of entropy is optimized. Na$\ddot{i}$ve and Booleanreasoning-based discretization searches categorical values by using Na$\ddot{i}$ve scaling the data, then finds the optimized dicretization thresholds through Boolean reasoning. Although the rough set analysis is promising for market timing, there is little research on the impact of the various data discretization methods on performance from trading using the rough set analysis. In this study, we compare stock market timing models using rough set analysis with various data discretization methods. The research data used in this study are the KOSPI 200 from May 1996 to October 1998. KOSPI 200 is the underlying index of the KOSPI 200 futures which is the first derivative instrument in the Korean stock market. The KOSPI 200 is a market value weighted index which consists of 200 stocks selected by criteria on liquidity and their status in corresponding industry including manufacturing, construction, communication, electricity and gas, distribution and services, and financing. The total number of samples is 660 trading days. In addition, this study uses popular technical indicators as independent variables. The experimental results show that the most profitable method for the training sample is the na$\ddot{i}$ve and Boolean reasoning but the expert's knowledge-based discretization is the most profitable method for the validation sample. In addition, the expert's knowledge-based discretization produced robust performance for both of training and validation sample. We also compared rough set analysis and decision tree. This study experimented C4.5 for the comparison purpose. The results show that rough set analysis with expert's knowledge-based discretization produced more profitable rules than C4.5.

• Korean Journal of Heritage: History & Science
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• v.51 no.3
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• pp.4-31
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• 2018

It is difficult to ascertain exactly when the Hongjuupseong (Town Wall) was first constructed, due to it had undergone several times of repair and maintenance works since it was piled up newly in 1415, when the first year of the reign of King Munjong (the 5th King of the Joseon Dynasty). Parts of its walls were demolished during the Japanese occupation, leaving the wall as it is today. Hongseong region is also susceptible to historical earthquakes for geological reasons. There have been records of earthquakes, such as the ones in 1978 and 1979 having magnitudes of 5.0 and 4.0, respectively, which left part of the walls collapsed. Again, in 2010, heavy rainfall destroyed another part of the wall. The fortress walls of the Hongjuupseong comprise various rocks, types of facing, building methods, and filling materials, according to sections. Moreover, the remaining wall parts were reused in repair works, and characteristics of each period are reflected vertically in the wall. Therefore, based on the vertical distribution of the walls, the Hongjuupseong was divided into type I, type II, and type III, according to building types. The walls consist mainly of coarse-grained granites, but, clearly different types of rocks were used for varying types of walls. The bottom of the wall shows a mixed variety of rocks and natural and split stones, whereas the center is made up mostly of coarse-grained granites. For repairs, pink feldspar granites was used, but it was different from the rock variety utilized for Suguji and Joyangmun Gate. Deterioration types to the wall can be categorized into bulging, protrusion of stones, missing stones at the basement, separation of framework, fissure and fragmentation, basement instability, and structural deformation. Manually and light-wave measurements were used to check the amount and direction of behavior of the fortress walls. A manual measurement revealed the sections that were undergoing structural deformation. Compared with the result of the light-wave measurement, the two monitoring methods proved correlational. As a result, the two measuring methods can be used complementarily for the long-term conservation and management of the wall. Additionally, the measurement system must be maintained, managed, and improved for the stability of the Hongjuupseong. The measurement of Nammunji indicated continuing changes in behavior due to collapse and rainfall. It can be greatly presumed that accumulated changes over the long period reached the threshold due to concentrated rainfall and subsequent behavioral irregularities, leading to the walls' collapse. Based on the findings, suggestions of the six grades of management from 0 to 5 have been made, to manage the Hongjuupseong more effectively. The applied suggested grade system of 501.9 m (61.10%) was assessed to grade 1, 29.5 m (3.77%) to grade 2, 10.4 m (1.33%) to grade 3, 241.2 m (30.80%) and grade 4. The sections with grade 4 concentrated around the west of Honghwamun Gate and the east of the battlement, which must be monitored regularly in preparation for a potential emergency. The six-staged management grade system is cyclical, where after performing repair and maintenance works through a comprehensive stability review, the section returned to grade 0. It is necessary to monitor thoroughly and evaluate grades on a regular basis.

• Journal of Radiation Protection and Research
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• v.39 no.2
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• pp.118-126
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• 2014

A survey was conducted on perceptions, knowledge, and attitudes of elementary, middle, and high school students, who will lead public opinion in the future, regarding irradiated food, nuclear power generation, and medical radiation. These topics urgently require general social acceptability among various fields in which radiation is used. Educational methods to enhance social acceptability were partially discovered. First, it is necessary to implement different strategies when designing courses for female and male students. Male students have higher levels of objective knowledge (p<0.039) of irradiated food, necessity (p<0.001) and objective knowledge (p<0.001) of nuclear power generation, approval of building a nuclear power plant in the nation (p<0.001), necessity (p<0.001) and objective knowledge (p<0.001) of medical radiation, and attitudes regarding using medical radiation (p<0.007, p<0.001). Second, the educational effect of explanations to help increase national understanding of the necessity and safety of nuclear power generation will increase if information on the necessity and safety of medical radiation is provided as well. Both male and female students perceived that medical radiation is the most necessary (p<0.001), medical radiation is the safest (p<0.001), and nuclear power generation is the least safe (p<0.013). Moreover, the correlation between medical radiation and nuclear power generation was the highest. Third, there is a need for different lectures between classes, since the patterns of perception vary according to the field of radiation use among elementary, middle, and high school students. Elementary school students had high interest in education on nuclear power generation (p<0.005), perceived that irradiated food is safe (p<0.001), and had the most positive attitude toward consuming irradiated food (p<0.001). Middle school students had high interest in education on nuclear power generation (p<0.018), perceived that nuclear power generation (p<0.001) and medical radiation (p<0.002) are safe, and had the most positive attitude toward using radiation for treatment (p<0.001). High school students had the highest level of objective knowledge on nuclear power generation (p<0.001) and medical radiation (p<0.001), and perceived that medical radiation is the most necessary (p<0.017); however, they perceived that nuclear power generation is the least safe (p<0.001). Attitudes toward irradiated food intake (p<0.001) and approving construction of a nuclear power plant in their neighborhood (p<0.001) were both low. Fourth, it is necessary to provide educational programs to change perceptions and improve attitudes rather than providing education focused on objective knowledge. There was no correlation between objective knowledge and necessity of irradiated food, objective knowledge and safety and interest in education on nuclear power generation, and objective knowledge and interest in education and information acquirement regarding medical radiation. In particular, high school students had the highest level of objective knowledge and yet had the least positive attitudes toward approving construction of nuclear power plants in their neighborhood and intake of irradiated food. Therefore, to increase the social acceptability of using nuclear energy and radiation in Korea, it is desirable to provide strategic educational programs to improve perceptions, knowledge, and attitudes regarding the necessity and safety of their use.

• Journal of Intelligence and Information Systems
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• v.23 no.3
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• pp.1-27
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• 2017

It is known that the economic sentiment index and macroeconomic indicators are closely related because economic agent's judgment and forecast of the business conditions affect economic fluctuations. For this reason, consumer sentiment or confidence provides steady fodder for business and is treated as an important piece of economic information. In Korea, private consumption accounts and consumer sentiment index highly relevant for both, which is a very important economic indicator for evaluating and forecasting the domestic economic situation. However, despite offering relevant insights into private consumption and GDP, the traditional approach to measuring the consumer confidence based on the survey has several limits. One possible weakness is that it takes considerable time to research, collect, and aggregate the data. If certain urgent issues arise, timely information will not be announced until the end of each month. In addition, the survey only contains information derived from questionnaire items, which means it can be difficult to catch up to the direct effects of newly arising issues. The survey also faces potential declines in response rates and erroneous responses. Therefore, it is necessary to find a way to complement it. For this purpose, we construct and assess an index designed to measure consumer economic sentiment index using sentiment analysis. Unlike the survey-based measures, our index relies on textual analysis to extract sentiment from economic and financial news articles. In particular, text data such as news articles and SNS are timely and cover a wide range of issues; because such sources can quickly capture the economic impact of specific economic issues, they have great potential as economic indicators. There exist two main approaches to the automatic extraction of sentiment from a text, we apply the lexicon-based approach, using sentiment lexicon dictionaries of words annotated with the semantic orientations. In creating the sentiment lexicon dictionaries, we enter the semantic orientation of individual words manually, though we do not attempt a full linguistic analysis (one that involves analysis of word senses or argument structure); this is the limitation of our research and further work in that direction remains possible. In this study, we generate a time series index of economic sentiment in the news. The construction of the index consists of three broad steps: (1) Collecting a large corpus of economic news articles on the web, (2) Applying lexicon-based methods for sentiment analysis of each article to score the article in terms of sentiment orientation (positive, negative and neutral), and (3) Constructing an economic sentiment index of consumers by aggregating monthly time series for each sentiment word. In line with existing scholarly assessments of the relationship between the consumer confidence index and macroeconomic indicators, any new index should be assessed for its usefulness. We examine the new index's usefulness by comparing other economic indicators to the CSI. To check the usefulness of the newly index based on sentiment analysis, trend and cross - correlation analysis are carried out to analyze the relations and lagged structure. Finally, we analyze the forecasting power using the one step ahead of out of sample prediction. As a result, the news sentiment index correlates strongly with related contemporaneous key indicators in almost all experiments. We also find that news sentiment shocks predict future economic activity in most cases. In almost all experiments, the news sentiment index strongly correlates with related contemporaneous key indicators. Furthermore, in most cases, news sentiment shocks predict future economic activity; in head-to-head comparisons, the news sentiment measures outperform survey-based sentiment index as CSI. Policy makers want to understand consumer or public opinions about existing or proposed policies. Such opinions enable relevant government decision-makers to respond quickly to monitor various web media, SNS, or news articles. Textual data, such as news articles and social networks (Twitter, Facebook and blogs) are generated at high-speeds and cover a wide range of issues; because such sources can quickly capture the economic impact of specific economic issues, they have great potential as economic indicators. Although research using unstructured data in economic analysis is in its early stages, but the utilization of data is expected to greatly increase once its usefulness is confirmed.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.4
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• pp.14-26
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• 2011

Imdaejeong Wonlim is located on the verge of Sangsa Village in Sapyeong-ri, Daepyeong-myeon, Hwasun-gun Gyeongsangnam-do toward Northwest. It was planned by Sa-ae, Minjuhyeon in 1862 on the basis of Gobanwon built by Nam Eongi in 16th century against the backdrop of Mt. Bongjeong and facing Sapyeong Stream. As water flows from west to east in the shape of crane, this area is a propitious site standing for prosperity and happiness. This area shows a distinct feature of Wonlim surrounding the Imdaejeong with multi layers as consisting of 5 districts - front yard where landmark stone with engraved letters of 'Janggujiso of Master Sa-ea' and junipers are harmoniously arranged, internal garden of upper pavilion ranging from a pavilion to square pond with a little island in the middle, Sugyeongwon of under pavilionu consisting of 2 ponds with a painting of three taoist hermits, forest of Mt. Bonggeong and external garden including Sapyeong Stream and farmland. According to documentation and the results of on-site investigation, it is certainly proved that Imdaejeong Wonlim was motivated by Byeoseo Wonlim which realized the idea of 'going back to hometown after resignation' following the motives of Janggujiso, a hideout aimed to accomplish the ideology, 'training mind and fostering innate nature,' on the peaceful site surrounded by water and mountain, as well as motives of Sesimcheo(洗心處) to be unified with morality of Mother Nature, etc. In addition, it implies various imaginary landscapes such as Pihangji, Eupcheongdang, square pond with an island and painting of three Taoist hermits based on a notion that 'the further scent flies away, the fresher it becomes,' which is originated from Aelyeonseol(愛蓮說). In terms of technique of natural landscape treatment, divers techniques are found in Imdaejeong Wonlim such as distant view of Mt. Bongjeong, pulling view with an intention of transparent beauty of moonlight, circle view of natural and cultural sceneries on every side, borrowed scenary of pastoral rural life adopted as an opposite view, looked view of Sulyundaero, over looked view of pond, static view in pavilion and paths, close view of water space such as stream and pond, mushroom-and-umbrella like view of Imdaejeong, vista of pond surrounded by willows, imaginary view of engraved letters meaning 'widen knowledge by studying objectives' and selected view to comprise sunrise and sunset at the same time. In the beginning of construction, various plants seemed to be planted, albeit different from now, such as Ginkgo biloba, Phyllostachys spp., Salix spp., Pinus densiflora, Abies holophylla, Morus bombycis, Juglans mandschurica, Paulownia coreana, Prunus mume, Nelumbo nucifera, etc. Generally, it reflected dignity of Confucianism or beared aspect of semantic landscape implying Taoist taste and idea of Phoenix wishing a prosperity in the future. Furthermore, a diversity of planting methods were pursued for such as liner planting for the periphery of pond, bosquet planting and circle planting adopted around the pavilion, spot planting using green trees, solitary planting of monumentally planted Paulownia coreana and opposite planting presenting the Abies holophylla into yin and yang.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.1
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• pp.52-64
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• 2015

This research traced the characteristics of the semantic landscape, construction intent, landscape composition, and geomantic conditions of the area subject to the research based on the research methods of 'field investigation, document studies, and interviews,' centering around the entire area of Gokseong Hamheo-pavilion (Jeonnam Tangible Cultural Assets No. 160). The result of the research, specifically revealing the forms and methods by which the reciprocal view of nature and landscape composition appearing in the landscape of the entire area of Hamheo-pavilion, as part of the analysis and interpretation over the view-based construction characteristics and position of the entire area of Gokseong Hamheo-pavilion, can be summarized as follows. First, Hamheo-pavilion is a pavilion built as a resting area and as a venue for educational activities in 1543 in the nearby areas after Gwang-hyeon Sim founded Gunjichon-jeongsa for educational activities and dwelling purposes at Gunchon at the 30th year of King Jungjong. Gunchon, where Hamheo-pavilion and Gunjichon-jeongsa is located, exhibits the typical form having water in the front, facing Sunja-river(present Seomjin-river), and a mountain in the back side. Dongak-mountain, which is a guardian mountain, is in a snail-type form where cows leisurely ruminate and lie on the riverside, and the Hamheo-pavilion area is said to be an area bordering on one's way of enjoying peace and richness as it is a place with plentiful grass bushes available for cows to ruminate and lie down while sheppards may leisurely play their flutes at the riverside. The back hill of Hamheo-pavilion is a blood vessel that enters the water into the underwater palace of the turtle, and the building sitting on the turtle's back is Hamheo-pavilion, and the Guam-jodae(龜巖釣臺) and lava on the southern side below the cliff can be interpreted to be the underwater fairly land wanted by the turtle.6) Second, Hamheo-pavilion is the scenery viewpoint of Sungang-Cheongpung (3rd Scenery) and Seolsan-Nakjo(雪山落照, 9th Scenery) among the eight sceneries of Gokseong, while also the scenery viewpoint of Hamheo-Sunja(2nd Scenery) and Cheonma-Gwiam(天馬歸岩, 3rd Scenery) among the eight sceneries of Ipmyeon. On the other hand, the pavilion is reproduced through the aesthetics of bends through sensible penetration and transcendental landscape viewed based on the Confucian-topos and ethics as the four bends among the five bends of Sunja-river arranged in the 'Santaegeuk(山太極) and Sutaeguek(水太極, formation of the yin-yang symbol by the mountain and water)' form, which is alike the connection of yin and yang. In particular, when based on the description over Mujinjeong (3rd Bend), Hoyeonjeong(4th Bend), andHapgangjeong(2nd Bend) among the five bends of Sunja-river in the records of Bibyeonsainbangan-jido(duringthe 18th century) and Okgwahyeonji(1788), the scenery of the five bends of Sunja-river allow to glimpse into its reputation as an attraction-type connected scenery in the latter period of the Joseon era, instead of only being perceived of its place identity embracing the fairyland world by crossing in and out of the world of this world and nirvana. Third, Hamheo-pavilion, which exhibits exquisite aesthetics of vacancy, is where the 'forest landscape composed of old big trees such as oak trees, oriental oak trees, and pine trees,' 'rock landscape such as Guam-jodae, lava, and layered rocks' and 'cultural landscape of Gunchon village' is spread close by. In the middle, it has a mountain scenery composed of Sunja-river, Masan-peak, and Gori-peak, and it is a place where the scenery by Gori-peak, Masan-peak, Mudeung-mountain, and Seol-mountain is spread and open in $180^{\circ}$ from the east to west. Mangseo-jae, the sarangchae (men's room)of Gunjichon-jeongsa, means a 'house observing Seoseok-mountain,' which has realized the diverse view-oriented intent, such as by allowing to look up Seol-mountain or Mudeung-mountain, which are back mountains behind the front mountain, through landscape configuration. Fourth, the private home, place for educational activities, pavilion, memorial room, and graveyard of Gunji-village, where the existence and ideal is connected, is a semantic connected scenery relating to the life cycle of the gentry linking 'formation - abundance - transcendence - regression.' In particular, based on the fact that the descriptions over reciprocal views of nature regarding an easy and comfortable life and appreciations for a picturesque scene of the areas nearby Sunja-river composes most of the poetic phrases relating to Hamheo-pavilion, it can be known that Hamheo-pavilion is expressed as the key to the idea of 'understanding how to be satisfied while maintaining one's positon with a comfortable mind' and 'returning to nature,' while also being expressed of its pedantic character as a place for reclusion for training one's mind and training others through metaphysical semantic scenery.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.293-300
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• 2012

This study was to investigate the unsuitable rate of the storage facilities, the changes in corrosion process over time after installation according to the status, the time to install the facilities, years elapsed after facilities installation, inspection of methods and motivation, and so on, based on the results of the inspection at the petroleum storage facilities conducted by domestic soil-relate specialized agency to derive optimal management plans which meet the status of soil contamination facilities. The results showed that the facilities more than 5 years after the initial leak test at the time of the installation need to be inspected periodically by considering costs of leak test and remediation of polluted soil. The inspection period can be decided by cost and leak test methods showing discrepancies for the results obtained from individual test whether it was direct or indirect. To compensate these matters, we suggested that the direct inspection method on regular schedule is recommended. On the other hand, the inspection can be voluntarily completed to ease burden of the results by inspection or equivalent level to this inspection method. Also, it may need improved construction supervision and performance test system to minimize the occurrence of the nature defects in installing the facilities as well as the upgrade program for the facilities during intervals of inspection period.