• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.78-99
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• 2020

The Buddha triad and 16 Arhat statues carved on the rock surface at Seongbulsa temple is the only domestic remaining example of all 16 Arhats, so its academic value is very high. However, it is severely damaged and so required a stability evaluation through study of digital documentation and precise diagnosis for the purpose of comprehensive conservation. This process established that the Buddha statues were of similar scale, while the Arhats showed a wide variety of sizes, and the two kith and kin in the volume were larger than the Arhats. It was estimated that the statues of food for Buddha are similar to the Arhat statues, and most of the statues are well-formed. The rock used to carve the Buddha statues is banded gneiss with distinct foliation, alternating between white bands of quartz and feldspar and black bands composed of biotite. The Buddha statues have been damaged by physical weathering, discoloration, and biological contamination. In damage evaluations, joint (3.6 crack index), peeling (5.2%), exfoliation (1.7%), and falling off (0.1%) were observed on the rock surface of the Buddha statues. In particular, due to severe biological weathering, stage 9 and 10 biological coverage of the rock surface accounted for 57.5% of the total area, and stages 5 to 8 also accounted for a high share at 22.3%. The discoloration factors were shown to be dark brown and white with Fe, Ca, and S, and a large amount of C detected in the blackened contaminants, and the damage weight high in all areas. Discontinuities in different directions were identified in the rock surface. Analysis of potential rock failure types indicated that there is a possibility of plane and toppling failure, but wedge failure is unlikely to occur. The mean ultrasonic velocity of the main rock surface was 2,463m/sec, the lower part of the left side with a large number of joints was relatively low, and the highly weathered (HW) type to the completely weathered (CW) type concentrated distribution, showing weak properties. For the Buddha statues, conservation treatment is required for about 14.9% of micro cracks and 58.9% of exfoliation cracks. In addition, in order to improve the conservation environment of the Buddha statues, maintenance of drainage and ground preparations for the rock surface gradient and plants are necessary, and protection facilities should be reviewed for long-term conservation and management purposes.

• Korean Chemical Engineering Research
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• v.60 no.2
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• pp.243-248
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• 2022

As the scope of use of portable and wearable electronic devices is expanding, the limitations of heavy and bulky solid-state batteries are being revealed. Given that, it is urgent to develop a small energy harvesting device that can partially share the role of a battery and the utilization of energy sources that are thrown away in daily life is becoming more important. Contact electrification, which generates electricity based on the coupling of the triboelectric effect and electrical induction when the two material surfaces are in contact and separated, can effectively harvest the physical and mechanical energy sources existing in the surrounding environment without going through a complicated intermediate process. Recently, the interest in the harvest and utilization of wind energy is growing since the wind is an infinitely ecofriendly energy source among the various environmental energy sources that exist in human surroundings. In this study, the optimization of the energy harvesting device for the effective harvest of wind energy based on the contact electrification was analyzed and then, the utilization strategy to maximize the utilization of the generated electricity was investigated. Natural wind based Fluttering TENG (NF-TENG) using fluttering film was developed, and design optimization was conducted. Moreover, the safe high voltage generation system was developed and a plan for application in the field requiring high voltage was proposed by highlighting the unique characteristics of TENG that generates low current and high voltage. In this respect, the result of this study demonstrates that a portable energy harvesting device based on the contact electrification shows great potential as a strategy to harvest wind energy thrown away in daily life and use it widely in fields requiring high voltage.

• Journal of the Korean earth science society
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• v.43 no.3
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• pp.367-385
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• 2022

This study evaluates the temperature and precipitation results in East Asia simulated from the Hadley Centre Global Environmental Model version 3 regional climate model (HadGEM3-RA) developed by the UK Met Office. The HadGEM3-RA is conducted in the Coordinated Regional climate Downscaling Experiment-East Asia (CORDEX-EA) Phase II domain for 15 year (2000-2014). The spatial distribution of rainbands produced from the HadGEM3-RA by the summer monsoon is in good agreement with the Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation of water resources (APRODITE) data over the East Asia. But, precipitation amount is overestimated in Southeast Asia and underestimated over the Korean Peninsula. In particular, the simulated summer rainfall and APRODITE data show the least correlation coefficient and the maximum value of root mean square error in South Korea. Prediction of temperature in Southeast Asia shows underestimation with a maximum error during winter season, while it appears the largest underestimation in South Korea during spring season. In order to evaluate local predictability, the time series of temperature and precipitation compared to the ASOS data of the Seoul Meteorological Station is similar to the spatial average verification results in which the summer precipitation and winter temperature underestimate. Especially, the underestimation of the rainfall increases when the amounts of precipitation increase in summer. The winter temperature tends to underestimate at low temperature, while it overestimates at high temperature. The results of the extreme climate index comparison show that heat wave is overestimated and heavy rainfall is underestimated. The HadGEM3-RA simulated with a horizontal resolution of 25 km shows limitations in the prediction of mesoscale convective system and topographic precipitation. This study indicates that improvement of initial data, horizontal resolution, and physical process are necessary to improve predictability of regional climate model.

• Ecology and Resilient Infrastructure
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• v.9 no.3
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• pp.194-205
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• 2022

Sandbars formed by sediment transportation and sedimentation are some of the most important habitats for specific wildlife and they provide an aesthetic landscape in streams. The purpose of this study was to understand the successional process of the colonization and development of early vegetation over time on sandbars exposed by the opening of a gate at a downstream weir. We selected the following four study sites in the Geumgang River, South Korea: three weir-upstream sites with different gate-opening times and a control site that was not affected by weir operation. Changes in the structural characteristics and spatial distribution of the riparian vegetation on the sandbars exposed after opening the gate at the weir were surveyed according to the different exposure periods of the sandbars at the study sites. The newly formed sandbars accounted for more than 33% of the area of the existing floodplain in the three weir-upstream sites of the Geumgang River after opening the gate at the weir. Nine main plant communities were distributed on the exposed sandbars. These communities were classified as annual mesophytic, perennial hydrophytic, perennial hygrophytic, subtree, and tree vegetation based on their species traits. As the duration of exposure of the sandbar increased, the area of the bare sandbar and the annual herbaceous and perennial hydrophytic communities decreased, and the areas occupied by perennial hygrophytic, subtree, and tree communities increased. Changes in vegetation on the sandbar were classified into three types of succession according to the condition of the aquatic habitat before the gate-opening and the degree of physical disturbance caused by the water flow after the gate-opening. The types of succession were: 1) succession starting from hydrophytes in the lentic aquatic zone, 2) succession starting from annual herbaceous hygrophytes in the lotic aquatic zone, and 3) willow-dominated succession in the disturbed channel side. Our results suggested that the dynamics of successional changes in vegetation should be considered during weir operation to ecologically manage the habitats and landscape of the fluvial landforms, including sandbars in streams.

• Economic and Environmental Geology
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• v.55 no.4
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• pp.317-338
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• 2022

Physicochemical characteristics and evaluation were studied by subdividing the concretes, bricks and earth pipes on the site of the Japanese Ministry of General Affairs in Joseon Dynasty, known as modern architecture, into three periods. Concretes showed similar specific gravity and absorption ratio, and large amounts of aggregates, quartz, feldspar, calcite and portlandite were detected. Porosity of the 1907 bricks were higher than those of 1910 and 1950 bricks. All earthen pipe is similar, but the earlier one was found to be more dense. Bricks and earthen pipes are dark red to brown in color within many cracks and pores, but the matrix of the earthen pipe is relatively homogeneous. Quartz, feldspar and hematite are detected in bricks, and mullite is confirmed with quartz and feldspar in earthen pipes, so it is interpreted that the materials have a firing temperature about 1,000 to 1,100℃. Concretes showed similar CaO content, but brick and earthen pipe had low SiO₂ and high Al₂O₃ in the 1907 specimen. However, the materials have high genetic homogeneity based on similar geochemical behaviors. Ultrasonic velocity and rebound hardness of the concrete foundation differed due to the residual state, but indicated relatively weak physical properties. Converting the unconfined compressive strength, the 1st extended area had the highest mean values of 45.30 and 46.33 kgf/cm², and the 2nd extended area showed the lowest mean values (20.05 and 24.76 kgf/cm²). In particular, the low CaO content and absorption ratio, the higher ultrasonic velocity and rebound hardness. It seems that the concrete used in the constructions of the Japanese Ministry of General Affairs in Joseon Dynasty had similar mixing characteristics and relatively constant specifications for each year. It is interpreted that the bricks and earthen pipes were through a similar manufacturing process using almost the same raw materials.

• Journal of Wetlands Research
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• v.25 no.2
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• pp.145-158
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• 2023

Constructed wetlands (CWs) are effective technologies for urban wastewater management, utilizing natural physico-chemical and biological processes to remove pollutants. This study employed a bibliometric analysis approach to investigate the progress and future research trends in the field of CWs. A comprehensive review of 100 most-recently published and open-access articles was performed to analyze the performance of CWs in treating wastewater. Spain, China, Italy, and the United States were among the most productive countries in terms of the number of published papers. The most frequently used keywords in publications include water quality (n=19), phytoremediation (n=13), stormwater (n=11), and phosphorus (n=11), suggesting that the efficiency of CWs in improving water quality and removal of nutrients were widely investigated. Among the different types of CWs reviewed, hybrid CWs exhibited the highest removal efficiencies for BOD (88.67%) and TSS (95.67%), whereas VSSF, and HSSF systems also showed high TSS removal efficiencies (83.25%, and 78.83% respectively). VSSF wetland displayed the highest COD removal efficiency (71.82%). Generally, physical processes (e.g., sedimentation, filtration, adsorption) and biological mechanisms (i.e., biodegradation) contributed to the high removal efficiency of TSS, BOD, and COD in CW systems. The hybrid CW system demonstrated highest TN removal efficiency (60.78%) by integrating multiple treatment processes, including aerobic and anaerobic conditions, various vegetation types, and different media configurations, which enhanced microbial activity and allowed for comprehensive nitrogen compound removal. The FWS system showed the highest TP removal efficiency (54.50%) due to combined process of settling sediment-bound phosphorus and plant uptake. Phragmites, Cyperus, Iris, and Typha were commonly used in CWs due to their superior phytoremediation capabilities. The study emphasized the potential of CWs as sustainable alternatives for wastewater management, particularly in urban areas.

• Journal of the Daesoon Academy of Sciences
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• v.43
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• pp.67-102
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• 2022

The purpose of this study is to analyze the human rights found in the North Korean Constitution and their core problem by focusing on elements of human rights suggested by Daesoon Jinrihoe's doctrine of Haewon-sangsaeng (解冤相生 the Resolution of Grievances for Mutual Beneficence). Haewon-sangsaeng is seemingly the only natural law that could resolve human resentment lingering from the Mutual Contention of the Former World while leading humans work for the betterment of one another. Haewon-sangsaeng, as a natural law, includes the right to life, the right to autonomous decision-making, and duty to act according to human dignity (physical freedom, the freedom of conscience, freedom of religion, freedom of speech, freedom of press, etc.), the right to equal treatment in one's social environment, and the right to ensure the highest level of health through treatment. The North Korean Constitution does not have a character as an institutional device to guarantee natural human rights, the fundamental principle of the Constitution, and stipulates the right of revolutionary warriors to defend dictators and dictatorships. The right to life is specified so that an individual's life belongs to the life of the group according to their socio-political theory of life. Rights to freedom are stipulated to prioritize group interests over individual interests in accordance with the principle of collectivism. The right to equality and the right to health justify discrimination through class discrimination. The right to life provided to North Koreans is not guaranteed due to the death penalty system found within the North Korean Criminal Code and the Criminal Code Supplementary Provisions. The North Korean regime deprives North Koreans of their right to die with dignity through public executions. The North Korean regime places due process under the direction of the Korea Worker's Party, recognizes religion as superstition or opium, and the Korea Worker's Party acknowledge the freedoms of bodily autonomy, religion, media, or press. North Koreans are classified according to their status, and their rights to equality are not guaranteed because they are forced to live a pre-modern lifestyle according to the patriarchal order. In addition, health rights are not guaranteed due biased availability selection and accessibility in the medical field as well as the frequent shortages of free treatments.

• The Korean Journal of Coaching Psychology
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• v.5 no.2
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• pp.127-170
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• 2021

This study developed a measure to measure wellness-seeking behavior in important areas of life for general adults in Korea and verified its validity. For the development of the wellness scale, 31 factors derived through literature review, expert interviews, in-depth interviews, open questionnaires 1 and 2, and 182 questions were selected as the final 10 factors and 99 questions. Through exploratory factor analysis of the results of the preliminary survey of 351 adults in Korea, 58 questions of 10 factors were derived, and some of the questions reflecting important concepts in each factor were revised, and this survey was conducted with 63 questions of 10 factors. In this survey conducted on 667 people, to verify the validity of the composition concept of this test, the entire sampling was divided into two groups, one group was subjected to exploratory factor analysis, and the other group was subjected to confirmatory factor analysis. As a result of exploratory factor analysis, 63 questions of 10 factors (work, community, family, others, economic power, self-esteem, leisure, physical health, spirituality, and self-growth) were finally derived, and confirmatory factor analysis using the structural equation model verified that the model fit criteria were met. Convergence validity was verified using the K-MHC-SF and Wellness Index for Workers to verify whether the derived wellness scale and its sub-factors actually measure wellness. As a result of analyzing the relationship between the variables and factors of the Subjective Happiness Scale and Life Scale to verify the validity related to the criteria, it was found to be a significant correlation. As a result of confirming the significance of each path through multiple regression analysis, the 'self-esteem' on the wellness scale was identified as the most important factor influencing subjective happiness and life satisfaction. Finally, discussions on this research process and results, academic significance and practical significance, limitations, and future research directions were presented.

• Korean Journal of Social Welfare Studies
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• v.41 no.4
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• pp.189-224
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• 2010

Nowadays Korean society has a fast growing population of North Korean immigrant youth. Especially, North Korean immigrant youth, who are discontinuing formal education, experience difficulties in social exclusion and adaptation. Therefore, the purpose of this study was to understand the experiences of adaptation and social support of North Korean immigrant youth discontinuing formal education, and to seek affirmative supporting plans and solutions for their adaptation. The methodology utilized for this study was a case study research. On the basis of the results and categorization, 'a network between overall categories and of early adaptation' was derived. The major findings of this study are summarized as follows. First, the participants of this study experienced major difficulties during 'economical adaptation', and their economical adaptation was strongly interrelated with their 'educational adaptation'. The discontinuing of their education resulting from their fleeing period caused 'academic differential and age disparity.' Thus they could not enroll in the formal education system, and their insufficient educational background resulted in low wages and overwork due to manual labor jobs. Second, participants recognized 'interpersonal relations' as the most essential factor in adaptation, and 'social support' from the interpersonal relations played an important role in adaptation to and comfort in Korean society. 'Interactions with South Koreans' was recognized as a significant resource for gaining informational and appraisal support, but was not activated satisfactorily. On the other hand, interaction with North Korean immigrants was avoided by the reason that 'there's nothing to learn', however emotional support from North Korean immigrants of close relationship played an important role in participants' adaptation, especially in all aspects of psychological adaptation. Third, participants experienced a lot of difficulties and stresses in their 'physical health and psychological adaptation'. Their chronic diseases worsened by remaining untreated, and female perceived symptoms were observed more often than in male. Meanwhile, excessive 'stresses' from the unfamiliar environment of South Korea negatively affected their psychological adaptation. However, they were satisfied with sense of liberty and security from living in a democratic society.

• Journal of Environmental Impact Assessment
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• v.32 no.6
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• pp.577-589
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• 2023

In Korea, the technical techniques for assessing visual impacts are standardized, but the methods for assessing the marine landscape itself are not standardized and need to be improved. In particular, in the landscape impact assessment of offshore wind power generation in Korea, it is necessary to recognize the landscape itself as a receptor and prepare a system that can evaluate the characteristics and sensitivity of the landscape. In this study, we propose an evaluation method for preparing a marine landscape quality assessment document that reflects the project characteristics of offshore wind power projects, and examine the possibility of utilization by applying it to actual project sites as an example. To evaluate the quality of marine scenery in offshore wind power projects, evaluation items of landscape characteristics, physical characteristics, and socio-cultural characteristics were evaluated based on the preliminary survey contents, and the quality of marine scenery was divided into five grades. Next, the evaluation criteria of the evaluation items were synthesized and the quality of the marine landscape was classified into preservation grade (grade 5), semi-preservation grade (grade 4), buffer grade (grade 3), semi-improvement grade (grade 2), and improvement grade (grade 1). In addition, the Sinan-Ui Offshore Wind Farm, an actual project site, was randomly selected to conduct the evaluation process and examine its utilization. This study aims to complement the existing method of visual impact assessment in offshore wind power projects and evaluate the quality of the marine landscape itself to effectively conserve marine landscape resources during offshore wind power projects. Rather than relying on mechanical and quantitative evaluation, this study is expected to be used as a basis for comprehensive understanding of the location and socio-cultural characteristics of the project site and for communication and cooperation with stakeholders.