• Journal of Conservation Science
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• v.36 no.6
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• pp.494-504
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• 2020

Ten historic sites (denoted as A- J in this study) of a tomb were found during the construction of the east-west expressway in District 2 of Hyangnam, Hwaseong, which is implemented by the Gyeonggi-do headquarters of the Korea Land & Housing Corporation. Thetombswere first detected at siteH, and further investigations revealed various tombs from the Three Kingdoms period; artifacts such as gilt-bronze shoes and caps were excavated from wooden coffins in the tombs. The pottery examined in this study was the only pottery artifact excavated from the site. Its raw clay was soft and loose, reddish brown, and had quartz and feldspar particles of < 1 mm, which appeared to have been added as reinforcing agents. The firing temperature of the pottery was estimated to be under 800-870 ℃ as the mica remains and tridimite, which is the phase transition mineral of quartz, was not produced; a slight endothermic peak was also detected because of the hydration of sericite at 800 ℃. The condition of the artifact was severely weakened because of various factors, such as soil pressure from the stratum formed over the site and repeated freezing and thawing. The artifact could not be collected alone, and thus, surrounding soil that had attached to the artifact was also collected; the artifact was transported to the laboratory and conservation treatment was conducted in a safe and systematic manner.

• Journal of Environmental Impact Assessment
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• v.31 no.6
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• pp.359-368
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• 2022

It is essential to increase the implementation rate in order to increase the effectiveness of mitigation measures that can mitigate the negative impact of development projects. In the case of Environmental Impact Assessment (EIA),research on the implementation evaluation of development projects is insufficient, even though the effectiveness of mitigation measures has been steadily raised. Therefore, this study evaluated the implementation rate of the mitigation measures and identified the cause of the difference in the implementation rate for each mitigation measures in order to understand the current status of the ecological mitigation measures. The implementation rate of urban and road development projects mitigation measures was 56.0% and 64.4%, respectively. the implementation rate of 'Monitoring' mitigation measures was the highest in all development project. But, 'Habitat creation' and 'Accident prevention measures' were low. In addition, it was found that the implementation rate of the mitigation measures were high when the contents of the mitigation measure described in the report were specific. Through this study, it was found that in order to increase the implementation rate of the EIA ecological environment animal mitigation measures, it is necessary to reflect the environmental and geographical characteristics of the target site in detail. Furthermore, it is judged that this study can be used as a basic basis for enhancing the effectiveness of the EIA system introduced to mitigate the negative impact on the environment.

• Journal of the Korean GEO-environmental Society
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• v.24 no.4
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• pp.23-29
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• 2023

Ground subsidence shows a mechanism in which the upper ground collapses due to the formation of a cavity due to the movement of soil particles in the ground due to the formation of a waterway because of damage to the water supply/sewer pipes. As a result, cavity is created in the ground and the upper ground is collapsing. Therefore, ground subsidence frequently occurs mainly in downtown areas where a large amount of underground facilities are buried. Accordingly, research to predict the risk of ground subsidence is continuously being conducted. This study tried to present a ground subsidence risk prediction model for two districts of ○○ city. After constructing a data set and performing preprocessing, using the property data of underground facilities in the target area (year of service, pipe diameter), density of underground facilities, and ground subsidence history data. By applying the dataset to the machine learning model, it is evaluated the reliability of the selected model and the importance of the influencing factors used in predicting the ground subsidence risk derived from the model is presented.

• Journal of Teachers' Pension
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• v.3
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• pp.207-252
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• 2018

현행 사학연금법은 공무원연금법 제46조 제1항 제4호 "정원 감소로 퇴직한 때부터 연금 지급" 조항을 준용함에 따라 정원감축 및 폐교에 따른 퇴직을 할 경우 법에 명시된 연금지급 개시연령이 아닌 퇴직 후 5년 이후에 조기연금을 지급하도록 하고 있다. 본 연구의 목적은 현행 지급개시연령 규정의 타당성을 검토하고 개선방안을 제시하는데 있다. 이를 위해 사학연금 지급개시연령 현황 및 사립학교 폐교 현황과 사학연금이 공무원연금법을 준용함으로써 발생하는 문제점 및 현행 규정에 따른 연금지급 시 사학연금재정에 미치는 영향을 분석하고 법 개정의 타당성을 검토하여 개선방안을 모색하였다. 주요 연구결과는 다음과 같다. 65세 정년이 되어 은퇴하지 않고 중도에 퇴직하거나 고용이 취소되어 지급개시연령 보다 훨씬 일찍 조기연금을 지급하게 될 경우에는 퇴직연금 자체가 노후소득보장제도이기 보다는 실업급여의 성격으로 전락하게 되는 측면이 있다. 또한, 폐교에 재직 중인 교직원은 근로가 가능한 연령과 건강상태임에도 불구하고 즉시 연금을 수급하게 됨으로써 재취업을 하지 않을 경우 연금에 대한 의존성이 높아지고 근로유인을 저해할 수 있다. 그리고 최근 잦은 폐교로 인한 연금수급자 과다 발생 및 재정적 지속가능성의 문제가 있다. 또한 사학연금 가입자와 공무원연금 가입자의 특성을 비교하면 중요한 차이점이 발견된다. 국공립학교의 경우에는 해당 학교가 폐교 또는 정원이 감소될 경우 다른 지역 학교로 해당 재직 교직원을 이동 배치하는 등의 대처 방안을 시행하기 때문에 사실상 퇴직하는 사례가 거의 없는 반면, 사학연금 가입자의 경우 공무원연금 가입자에 비해 상대적으로 고용불안에 노출되어 있고, 학령인구 감소 등으로 인해 사립학교 폐교 가능성이 상존하므로 이들에 대한 생활안정대책이 필요하다. 또한 공무원 조직의 개폐 및 정원 감소는 법령으로 정하고 있지만, 사립학교 교직원의 개폐 및 정원의 감소는 사학기관의 특성에 따라 차이가 있다. 그리고 공무원의 경우 공무원연금의 대상이면서도 고용형태의 상대적 취약점을 감안하여 임기제 공무원의 경우 고용보험의 가입이 일부 허용되나, 사학연금 가입자의 경우에는 전면적으로 가입이 제한되어 직역연금 간 형평성 문제가 발생하고 있다. 그리고 국민연금과 비교할 때 다음과 같은 차이점이 있다. 국민연금법의 경우 사업장가입자로 적용받고 있다 하더라도 준용법과 같은 사립학교 폐교 시 조기연금 수급 규정이 없으며, 고용보험법의 적용으로 실직 시 실업급여 등의 대응책이 있긴 하나 연금 수급을 통한 소득보장 수준에는 못 미치는 제도적 보완책을 갖추고 있다. 또한, 국민연금 가입자는 고용보험에 적용되나, 사학연금 가입자는 실업상태에 놓였을 경우 고용보험의 적용을 받지 못한다는 점에서 차이가 존재한다. 이에 다음과 같은 개선방안을 제시하였다. 폐교 시 사학연금 가입자의 생활안정을 위해 고용보험 가입을 검토할 필요가 있고, 재정안정화를 위해 연금을 전액지급하기 보다는 퇴직일부터 지급개시연령까지의 잔여기간에 따라 차등지급하는 방안을 모색해 볼 수 있으며, 고용보험법상의 실업급여 제도를 원용하고 소정의 연금지급기간을 설정하여 연금을 지급하는 방안을 고려할 필요가 있다. 이에 더하여 사학연금제도 내에서 별도의 고용보험기금을 마련하는 방안도 모색해볼 필요가 있다.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.27 no.3
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• pp.45-56
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• 2024

Heavy metals emitted from urban development do not decompose in the soil and remain for long periods, continually impacting the environment. Since the mid-1990s, there has been increasing societal concern in South Korea regarding soil contamination, prompting various legislative revisions to reduce pollution. This study utilizes the Environmental Impact Assessment Support System (EIASS) to investigate projects in the metropolitan area that have exceeded the Ministry of Environment's soil contamination concern levels from 1989 to 2022 and to examine improvements in the environmental impact assessment (EIA) process. The results reveal that the average concentrations of nine contaminants-cadmium (Cd), copper (Cu), arsenic (As), mercury (Hg), lead (Pb), hexavalent chromium (Cr6+), zinc (Zn), nickel (Ni), and fluoride (F)-have all increased over the years. Among these, Zn had the highest relative proportion, with 37.5% of the 40 sites exceeding environmental concern levels. Investigation of 19 specific projects at these exceedance sites showed that only 7 had documented analyses of contamination causes and remediation plans, and just one had contracted additional remediation services, though results from these efforts were found to be lacking. Furthermore, since 2019, a significant proportion of these sites were involved in residential developments, likely due to government initiatives in new city development and extensive housing supply plans. This research emphasizes the importance of public disclosure of the processes and outcomes of remediation efforts on historically contaminated soils prior to project development. It discusses improvements to the EIA by reviewing current legislation and international examples. The findings of this study are expected to heighten public awareness about heavy metal contamination and enhance transparency in soil remediation efforts, contributing to sustainable environmental management and development.

• Journal of Soil and Groundwater Environment
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• v.14 no.2
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• pp.33-44
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• 2009

The objective of the study was to develop a hybrid technology integrating biological and physicochemical technologies to efficiently remediate arsenic contaminated lands such as abandoned mine area. The tailing soil samples contaminated with As at a high level were obtained from Songchon abandoned mine, and the content of arsenic and heavy metals as well as physicochemical properties and mineral composition were investigated. In addition, two sets of sequential extraction methods were applied to analyze chemical speciations of arsenic and heavy metals to expect their leachability and mobility in geoenvironment. Based on these geochemical data of arsenic and heavy metal contaminants, column-type experiments on the bioleaching of arsenic were undertaken. Subsequently, experiments on the hybrid process incorporating bioleaching and electrokinetics were accomplished and its removal efficiency of arsenic was compared with that of the individual electrokinetic process. With the results, finally, the feasibilty of the hybrid technnology was evaluated. The arsenic removal efficiencies of the individual electrokinetic process (44 days) and the hybrid process incorporating bioleaching (28 days) and electrokinetics (16 dyas) were measured 57.8% and 64.5%, respectively, when both two processes were operated in an identical condition. On the contrary, the arsenic removal efficiency during the bioleaching process (28 days) appeared relatively lower (11.8%), and the result indicates that the bioleaching process enhanced the efficacy of the electrokinetic process as a result of mobilization of arsenic rather than removed arsenic by itself. In particular, the arsenic removal rate of the electrokinetics integrated with bioleaching was observed over than 2 times larger than that obtained by the electrokinetics alone. From the results of the study, if the bioleaching which is considered a relatively economic process is applied sufficiently prior to electrokinetics, the removal efficiency and rate of arsenic can be significantly improved. Consequently, the study proves the feasibility of the hybrid process integrating both technologies.

• Economic and Environmental Geology
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• v.28 no.6
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• pp.579-585
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• 1995

The Samkwang mine is Cretaceous gold-silver-bearing deposits located in the western part of the Ogcheon belt The ore deposits have been emplaced within granite gneiss of the Precambrian age. The Au-Ag deposits are hydrothermal-vein type, characterized by arsenic-, gold- and silver-bearing sulphides, in addition to the principal ore-forming sulphides arsenopyrite, galena, sphalerite, chalcopyrite, pyrite and pyrrhotite. Their proven reserves are 355,000 MT, and grades are 8.4 g Au/t and 13.6 g Ag/t. On the basis of their structural characters, the Au-Ag-bearing quartz veins are classified into three types of ore veins; (1) The Main vein shows $N40^{\circ}-80^{\circ}E$ strike and $55^{\circ}-90^{\circ}SE$ dip, (2) the Sangban vein shows E-W strike and $30^{\circ}-40^{\circ}S$ dip, and (3) the Gukseong vein has $N25^{\circ}-40^{\circ}W$strike and $65^{\circ}-80^{\circ}SW$ dip. The emplacements of the ore veins are closely related to the minimum stress axis $({\sigma}_3)$ during the strike-slip movement of the study area. The ore-bearing veins filled with extension fractures during strike-slip movements were sequentially emplaced as follows: I) When ${\sigma}_1$ operates obliquely to NE-series discontinous surface, the Main fault zone $(F_1)$ developes. 2) During the same time, extension fractures ($T_1$ Gukseong veins) take place. 3) When the fault progress continuously, the existing $T_1$, may be high angle and $T_2$ (Daehung vein) developes continuously. 4) When ${\sigma}_1$ changes to sinistral sense, $T_3$ (basic dyke) occurs. 5) When a reverse fault becomes active, the Sangban vein is branched from the Guksabong vein.

• Archives of design research
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• v.15 no.4
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• pp.275-284
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• 2002

To improve the social and economic position of the disabled people and secure their human rights, an integrated society should be buill. To build such a society, an adequate access should be provided to the movement or in using buildings or facilities. The inconveniences from social life on the part of the disabled people might not result from their impairment or disability, but from physical and social barriers in the environment surrounding them. Therefore, it is necessary to reconstruct entire systems of the society as a disabled people-friendly structure in order to remove those barriers, make them stand their own feet in our communities and freely participate in the social activities. This will eventually lead to build a society in which all people including the disabled people can use those facilities in a more convenient way. It is almost impossible for the disabled people to safely and conveniently access to and use facilities and equipments and freely move to their desired places, without any help from others in Korea. Even though, there are currently many disabled people-related convenience facilities, they have been independently built without a connection with other facilities and buildings, thus not greatly useful. Even when convenience facilities have been built, mostly they are superficially set up; therefore, in many cases, the disabled peOple cannot use those facilities. In this. research, I tried a new concept of mobile wheelchair lift design, which the disabled people can operate without restrictions, when using the public facilities. The key to this research was to develop the existing import-oriented simple functional products to a new system with functional safety and high quality orientation. Also, this research aimed at bringing an. import substitution effect, as well as preempting the mobile wheelchair lift market by advancing into overseas markets through application of new image designs in the field of disabled people aid equipments.

• Journal of Oral Medicine and Pain
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• v.36 no.3
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• pp.147-160
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• 2011

Eugenol (4-allyl-2-methoxyphenol) is a natural phenolic constituent extensively used in dentistry as a component of zinc oxide eugenol cement and is applied to the mouth environment. Chios gum mastic (CGM) is a resinous exudate obtained from the stem and the main leaves of Pistacia lenticulus tree native to Mediterranean areas. This study was undertaken to investigate the synergistic apoptotic effect of co-treatment with a natural product, CGM and natural phenolic compound, eugenol on SCC25 human tongue squamous cell carcinoma cell line. To investigate whether the co-treatment with eugenol and CGM compared to each single treatment efficiently reduces the viability of SCC25 cells, MTT assay was conducted. Induction and augmentation of apoptosis were confirmed by Hoechst staining, TUNEL staining and DNA hypoploidy. Westen blot analysis and immunofluorescent staining were performed to study the alterations of the expression level and the translocation of apoptosis-related proteins in co-treatment. In this study, co-treatment of with eugenol and CGM on SCC25 cells showed several lines of apoptotic manifestation such as nuclear condensations, DNA fragmentation, the increase and decrease of Bax and Bcl-2, decrease of DNA content, the release of cytochrome c into cytosol, translocation of AIF and DFF40 (CAD) onto nuclei, and activation of caspase-3, caspase-6 caspase-7, caspase-9, PARP, Lamin A/C and DFF45 (ICAD) whereas each single treated SCC25 cells did not show or very slightly these patterns. Although the single treatment of 40 ${\mu}g$/ml CGM and 0.5 mM eugenol for 24 h did not induce apoptosis, the co-treatment of these reagents prominently induced apoptosis. Therefore our data provide the possibility that combination therapy with CGM and eugenol could be considered as a novel therapeutic strategy for human oral squamous cell carcinoma.

• Journal of Environmental Impact Assessment
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• v.28 no.5
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• pp.440-456
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• 2019

The controversy of the risk perception related to particulate matters becomes significant. Therefore, in order to understand the nature of the particulate matters, we gathered articles and comments in on-line community related to bicycling which is affected by exposure of the particulate matters. As a result, firstly, the government - led particulate matter policy was strengthened and segmented every period, butthe risk perception related to particulate matters in the bicycle community has become active and serious. Second, as a result of analyzing the perception change of outdoor activities related to particulate matters, bicycle users in community showed a tendency of outdoor activity depending on the degree of particulate matters ratherthan the weather. In addition, the level of the risk perception related to particulate matters has been moved from fears of serious threat in daily life and health, combined with the disregard of domestic particulate matter levels or mask performance. Ultimately, these risk perception related to particulate matters have led some of the bicycling that were mainly enjoyed outdoors to the indoor space. However, in comparison with outdoor bicycling enjoyed by various factors such as scenery, people, and weather, the monotonous indoor bicycling was converted into another type of indoor exercise such as fitness and yoga. In summary, it was derived from mistrust of excessive information or policy provided by the government or local governments. It is considered that environmental policy should be implemented after discussion of risk communication that can reduce the gap between public anxiety and concern so as to cope with the risk perception related to particulate matters. Therefore,this study should be provided as an academic basis for the effective communication direction when decision makers establish the policy related to particulate matters.