• Title/Summary/Keyword: disturbance system

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Structure and Understory Species Diversity of Pinus parviflora - Tsuga sieboldii Forest in Ulleung Island (울릉도 섬잣나무-솔송나무림의 구조 및 하층식생의 종 다양성)

  • Cho, Yong Chan;Hong, Jin Ki;Cho, Hyun Je;Bae, Kwan Ho;Kim, Jun Soo
    • Journal of Korean Society of Forest Science
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    • v.100 no.1
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    • pp.34-41
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    • 2011
  • Vegetation structure, composition and diversity were quantified for 10 samples ($10m{\times}10m$) representing woody vegetation and for 30 samples ($1m {\times}3m$) representing understory vegetation in Pinus parviflora and Tsuga sieboldii forest of Taeharyeong, Ulleung-gun (Gyeongsangbuk-do). P. parviflora was limitedly advanced to sapling layer from seedling stage, and based on Mantel tests, composition of canopy layer was not established in ground woody vegetation. Non-metric multidimensional scaling revealed influence of biotic and abiotic factors in species composition of woody and understory vegetation. In the result of multiple regression model, abundance of P. parviflora (density and breast height area) and percent cover of woody debris were significant predict variables for understory diversity. These results suggest that relatively large disturbance is required for regeneration of P. parviflora and T. sieboldii forest, and control of expansion of monocultural understory species that monopolize resources such as Carex blepharicarpa and Maianthemum dilatatum, is necessary for maintenance of diversity.

A Study on the Data Cleaning and Standardization of National Ecosystem Survey in Korea (전국자연환경조사 데이터 정제와 표준화 방안 연구)

  • Kwon, Yong-Su;Song, Kyohong;Kim, Mokyoung;Kim, Kidong
    • Korean Journal of Ecology and Environment
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    • v.53 no.4
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    • pp.380-389
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    • 2020
  • Research on diagnosing and predicting the response of ecosystems caused by environmental changes such as artificial disturbance and climate change is emerging as the most important issue of biodiversity and ecosystem researches. This study aims to clean, standardize, and provide the results of National Ecosystem Survey which should be considered fundamentally in diagnosing and predicting ecosystem changes in the form of dataset. To refine and clean the dataset we developed a simple verification program based on the fifth National Ecosystem Survey Guideline and applied that program to the data from the second (1997~2005), third (2006~2013) and fourth (2014~2018) National Ecosystem Survey. Data quality control processes were implemented including (1) standardization of terminology, (2) similar data table integration, (3) unnecessary attribute and error elimination, (4) unification of different input items, (5) data arrangement in codes, and (6) code mapping for input items. These approaches and methods are the first attempt propose an option for ecological data standardization in Korea. The standardized dataset of National Ecosystem Survey in Korea will be easily accessible, reusable for both researchers and public. In addition, we expect it will contribute to the establishment of diverse environmental policies concerning environmental assessments, habitat conservation, prediction of endangered species distribution and ecological risks due to climate change. The dataset through this study is open freely online via EcoBank (nie-ecobank.kr) which is the first ecological information portal system in Korea developed by National Institute of Ecology.

Risk of Carbon Leakage and Border Carbon Adjustments under the Korean Emissions Trading Scheme

  • Oh, Kyungsoo
    • Journal of Korea Trade
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    • v.26 no.2
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    • pp.45-64
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    • 2022
  • Purpose - This paper examines South Korea's potential status as a carbon leakage country, and the level of risk posed by the Korean emissions trading scheme (ETS) for Korean industries. The economic effects of border carbon adjustments (BCAs) to protect energy-intensive Korean industries in the process of achieving the carbon reduction target by 2030 through the Korean ETS are also analyzed. Design/methodology - First, using the Korean Input-Output (IO) table, this paper calculates the balance of emissions embodied in trade (BEET) and the pollution terms of trade (PTT) to determine Korean industries' carbon leakage status. Analyses of the risk level posed by carbon reduction policy implementation in international trade are conducted for some sectors by applying the EU criteria. Second, using a computable general equilibrium (CGE) model, three BCA scenarios, exemption regulations (EXE), reimbursement (REB), and tariff reduction (TAR) to protect the energy-intensive industries under the Korean ETS are addressed. Compared to the baseline scenario of achieving carbon reduction targets by 2030, the effects of BCAs on welfare, carbon leakage, outputs, and trading are analyzed. Findings - As Korea's industrial structure has been transitioning from a carbon importing to a carbon leaking country. The results indicate that some industrial sectors could face the risk of losing international competitiveness due to the Korean ETS. South Korea's industries are basically exposed to risk of carbon leakage because most industries have a trade intensity higher than 30%. This could be interpreted as disproving vulnerability to carbon leakage. Although the petroleum and coal sector is not in carbon leakage, according to BEET and PTT, the Korean ETS exposes this sector to a high risk of carbon leakage. Non-metallic minerals and iron and steel sectors are also exposed to a high risk of carbon leakage due to the increased burden of carbon reduction costs embodied in the Korean ETS, despite relatively low levels of trade intensity. BCAs are demonstrated to have an influential role in protecting energy-intensive industries while achieving the carbon reduction target by 2030. The EXE scenario has the greatest impact on mitigation of welfare losses and carbon leakage, and the TAF scenario causes a disturbance in the international trade market because of the pricing adjustment system. In reality, the EXE scenario, which implies completely exempting energy-intensive industries, could be difficult to implement due to various practical constraints, such as equity and reduction targets and other industries; therefore, the REB scenario presents the most realistic approach and appears to have an effect that could compensate for the burden of economic activities and emissions regulations in these industries. Originality/value - This paper confirms the vulnerability of the Korean industrial the risk of carbon leakage, demonstrating that some industrial sectors could be exposed to losing international competitiveness by implementing carbon reduction policies such as the Korean ETS. The contribution of this paper is the identification of proposed approaches to protect Korean industries in the process of achieving the 2030 reduction target by analyzing the effects of BCA scenarios using a CGE model.

A Method of Developing a Ground Layer with Risk of Ground Subsidence based on the 3D Ground Modeling (3차원 지반모델링 기반의 지반함몰 위험 지반 레이어 개발 방법)

  • Kang, Junggoo;Kang, Jaemo;Parh, Junhwan;Mun, Duhwan
    • Journal of the Korean GEO-environmental Society
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    • v.22 no.12
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    • pp.33-40
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    • 2021
  • The deterioration of underground facilities, disturbance of the ground due to underground development activities, and changes in ground water can cause ground subsidence accidents in the urban areas. The investigation on the geotechnical and hydraulic factors affecting the ground subsidence accident is very significant to predict the ground subsidence risk in advance. In this study, an analysis DB was constructed through 3D ground modeling to utilize the currently operating geotechnical survey information DB and ground water behavior information for risk prediction. Additionally, using these results, the relationship between the actual ground subsidence occurrence history and ground conditions and ground water level changes was confirmed. Furthermore, the methodology used to visualize the risk of ground subsidence was presented by reconstructing the engineering characteristics of the soil presented according to the Unified Soil Classification System (USCS) in the existing geotechnical survey information into the internal erosion sensitivity of the soil, Based on the result, it was confirmed that the ground in the area where the ground subsidence occurred consists of more than 40% of sand (SM, SC, SP, SW) vulnerable to internal erosion. In addition, the effect of the occurrence frequency of ground subsidence due to the change in ground water level is also confirmed.

A Study on the Improvement of Types and Grades of Forest Wetland through Correlation Analysis of Forest Wetland Evaluation Factors and Types (산림습원 가치평가 요소와 유형 및 등급의 상관성 분석을 통한 산림습원 유형 구분 및 등급의 개선 방안 연구)

  • Lee, Jong-Won;Yun, Ho-Geun;Lee, Kyu Song;An, Jong Bin
    • Korean Journal of Plant Resources
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    • v.35 no.4
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    • pp.471-501
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    • 2022
  • This study was carried out on 455 forest wetlands of south Korea for which an inventory was established through value evaluation and grade. Correlation analysis was conducted to find out the correlation between the types and grades of forest wetlands and 23 evaluation factors in four categories: vegetation and landscape, material circulation and hydraulics·hydrology, humanities and social landscape, and disturbance level. Through the improvement of types and grades of forest wetlands, it is possible to secure basic data that can be used in setting up conservation measures by preparing standards necessary for future forest wetland conservation and restoration, and to found a systematic monitoring system. First, between the type of forest wetland and size and accessibility showed a positive correlation, but the remaining items were analyzed to have negative or no correlation. In particular, it was found that there was no negative correlation or no correlation with the grades of forest wetland. Moreover, it was found that there was a very strong negative correlation with the weighted four category items. Thus, it is judged that improvement is necessary because there is an error in the weight or adjust the evaluation criteria of the value evaluation item, add an item that can increase objectivity. Especially, in the case of forest wetlands, the ecosystem service function due to biodiversity is the largest, so evaluation items should be improved in consideration of this. Therefore, it can be divided into five categories: uniqueness and rarity (15%), wildlife habitat (15%), vegetation and landscape (35%), material cycle·hydraulic hydrology (30%), and humanities and social landscape (5%). It will be possible to propose weights that can increase effectiveness.

The Job Stress and Mental Health of the Insurance Reviewer (보험심사 근무직의 직무스트레스와 정신건강)

  • Kyoungjin Song;Jeongwon Lee
    • Journal of Service Research and Studies
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    • v.11 no.1
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    • pp.31-44
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    • 2021
  • The net function of the domestic medical insurance system is highly regarded, but due to the problem of incomplete coverage, the public wants to secure coverage through private medical insurance subscription. As a result, the subscription rate of private medical insurance has recently increased, and the billing rate has also increased. As the number of people seeking private medical insurance increased, workers at private medical insurance companies are experiencing increased job stress and side effects, especially for insurance reviewers who are in charge of paying insurance, such as communicating with customers who claimed insurance and contributing to the company's profit. In response, this study analyzed the effects of job stress on mental health of insurance reviewers and conducted a descriptive survey study to reduce job stress of insurance reviewers and promote mental health. The analysis shows that job stress for insurance reviewers has a significant impact on mental health (+). In detail, job stress has a significant impact on all four factors: social performance and self-confidence, depression, sleeping disturbance and anxiety, and general well-being and vitality. This study showed that job stress in insurance reviewers has a significant (+) impact on mental health. Job stress can cause side effects in organizational aspects, such as reducing enthusiasm for job performance and increasing turnover and resignation rates, but it can also worsen individual physical health and cause diseases such as depression and anxiety, causing mental health to be impoverished. Therefore, in order to prevent this, appropriate work stress prevention methods and countermeasures should be provided to help reduce work stress and improve mental health.

Chinese Agrarian Resistance and A New Mediation of State-Society Relationship (중국 농민저항과 국가-사회 관계의 새로운 조정)

  • Lee, Ki-Hyun
    • Journal of International Area Studies (JIAS)
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    • v.15 no.1
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    • pp.61-82
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    • 2011
  • Public resistance is an essential factor of the democratization process. Due to this, public resistance has been recognized as an important element in discussing the democratization of China. Recently in China, and a new era of resistance especially the agrarian resistance has been being expanded. This paper identifies trends and characteristics of that. With searching changes in the relationship between the nation and the societies in China, we will check whether democratization can be built from the whole bottom of the nation's ideology or not. It is a paradox of china's economic growth that the peasant uprising increased is a factor to the growth. The farmers' smoldering discontent exploded with rage because rural communities have been forced to sacrifice during the growth. The authoritarian party-state system in China has been faced with the limits in calming the peasant revolt down with the traditional suppression and restriction. Even though the party-state system in China has accepted farmers' dissatisfaction somewhat, and it has tried to improve its image of a benevolent government and pursued buying stability strategy, the gap between urban and rural areas has been expanded in the sustainable economic development and modernization process, therefore the authorities could not soothe the farmers' sense of alienation. Accordingly, the peasant revolt has not flickered out easily, and has been getting uncontrolled across China. Resistance characteristics of Chinese farmers have also changed. In the past, they had been sporadic and indirect ways, whereas in recent years, they have changed into organized and active ways. Of course, it is generally evaluated that the party-state system has sustained a strong social control so far. Buying stability strategy has prevented farmers' complaints from spreading to a threat to its regime, because civil societies in rural areas have still weak foundations from being formed. The party-state system, because of tensions and conflicts, will control the growing powers of civil societies in rural areas with institutionalization of interaction between the nation and the societies, and they will induce street protests to legalized struggle for a while. However, the relationship between the state and the societies has already started new rearrangement, in terms of that the conflicts between the state and rural communities have continued, and the changes of resistance ways.

Effects of Nasal Continuous Positive Airway Pressure Application on Sympathetic Activation : Power Spectrum Analysis of Electrocardiogram in Obstructive Sleep Apnea Syndrome (폐쇄성 수면무호흡증에서 지속적 상기도 양압술 시행이 교감신경계 활성도에 끼치는 영향 : 심전도 스펙트럼 분석)

  • Youn, Tak;Park, Hae-Jeong;Kim, Eui-Joong;Jeong, Do-Un
    • Sleep Medicine and Psychophysiology
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    • v.7 no.1
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    • pp.43-50
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    • 2000
  • Objectives: Obstructive sleep apnea syndrome(OSAS) is known to be associated with the changes of autonomic nervous system (ANS). Nasal continuous positive airway pressure(nCPAP) treatment was found to correct abnormal ANS changes in OSAS but it remains to be further clarified. We aimed to assess the effects of nCPAP on ANS manifested on electrocardiogram, using spectrum analysis in the subjects with OSAS. Methods: Digital polysomnography was performed in 18 patients with OSAS(mean age $43.7{\pm}16.6$ years ; 17 males, 1 female ; mean respiratory disturbance index (RDI) $48.6{\pm}20.9$) for one baseline and another CPAP nights. From each night, 300 continuous beats of ECGs without artifact were chosen from both stage 2 sleep and REM sleep and they were used for power spectrum analysis. We compared between baseline and CPAP nights the heart rate variability including VLF(very low frequency power), LF (low frequency power), HF(high frequency power), R-R means, R-R variance, and LF/HF ratio, using Wilcoxon signed ranks test. Results: In all patients, nCPAP proved to be effective in relieving apneas and snoring. During nCPAP night compared with baseline night, decreases in VLF(p<0.05), LF(p<0.01), and R-R variance(p<0.05) were found in stage 2 sleep, and decreased LF(p<0.05) was found in REM sleep. No significant differences in each sleep stage were found in other variables between the two nights. Conclusion: Our findings suggest that OSAS increases the activity of sympathetic nervous system and nCPAP application effectively decreases the activity. And nCPAP does not appear to influence the parasympathetic nervous activity in OSAS.

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Human Parechovirus as an Important Cause of Central Nervous System Infection in Childhood (소아청소년기 중추신경 감염의 주요 원인으로서 Human Parechovirus의 의의)

  • Jung, Hyun Joo;Choi, Eun Hwa;Lee, Hoan Jong
    • Pediatric Infection and Vaccine
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    • v.23 no.3
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    • pp.165-171
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    • 2016
  • Purpose: Human parechovirus (HPeV) is an increasingly recognized pathogenic cause of central nervous system (CNS) infection in neonates. However, HPeV infections have not been studied in older children. This study determined the prevalence and clinical features of HPeV CNS infection in children in Korea. Methods: Reverse transcription polymerase chain reaction assays were performed using HPeV-specific, 5' untranslated, region-targeted primers to detect HPeV in cerebrospinal fluid (CSF) samples from children presenting with fever or neurologic symptoms from January 1, 2013, to July 31, 2014. HPeV genotyping was performed by sequencing the viral protein 3/1 region. Clinical and laboratory data were retrospectively abstracted from medical records and compared with those of enterovirus (EV)-positive patients from the same period. Results: Of 102 CSF samples, six (5.9%) were positive for HPeV; two of 21 EV-positive samples were co-infected with HPeV. All samples were genotype HPeV3. Two HPeV-positive patients were <3 months of age and four others were over 1 year old. While HPeV-positive infants under 1 year of age presented with sepsis-like illness without definite neurologic abnormalities, HPeV-positive children over 1 year of age presented with fever and neurologic symptoms such as seizures, loss of consciousness, and gait disturbance. The CSF findings of HPeV-positive patients were mostly within the normal range, whereas most (73.7%) EV-positive patients had pleocytosis. Conclusions: Although HPeV is typically associated with disease in young infants, the results of this study suggest that HPeV is an emerging pathogen of CNS infection with neurologic symptoms in older childhood.

Restoration of endangered orchid species, Dendrobium moniliforme (L.) Sw. (Orchidaceae) in Korea (멸종위기 난과 식물 석곡의 복원)

  • Kim, Young-kee;Kang, Kyung-Won;Kim, Ki-Joong
    • Korean Journal of Plant Taxonomy
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    • v.46 no.2
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    • pp.256-266
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    • 2016
  • A total of 13,000 individuals of Dendrobium moniliforme (L.) Sw. artificially propagated in laboratories and greenhouses were restored in their natural habitat of Bogildo Island, Wandogun, in the southern part of Korea in June of 2013. The growing conditions of the individuals were monitored for two years. The parental individuals for the restoration were obtained from a wild population in southern Korea, from which seeds were produced via artificial crossings. These seeds were germinated and cultivated in growing media and two-year-old plants were then grown in greenhouse beds. The genetic diversity among the propagated individuals was confirmed by examining DNA sequences of five regions of the chloroplast genome and the nuclear ITS region. The diversity values were as high as the average values of natural populations. All propagated individuals were transplanted into two different sites on Bogildo by research teams with local residents and national park rangers. After restoration, we counted and measured the surviving individuals, vegetative propagated stems, and growth rates in June of both 2014 and 2015. There was no human interference, and 97% of the individuals survived. The number of propagules increased by 227% in two years. In contrast, the average length of the stems decreased during the period. In addition, different survival and propagation rates were recorded depending on the host plants and the restored sites. The shaded sides of rock cliffs and the bark of Quercus salicina showed the best propagation rates, followed by the bark of Camellia japonica. A few individuals of D. moniliforme successfully flowered, pollinated, and fruited after restoration. Overall, our monitoring data over two years indicate that the restored individuals were well adapted and vigorously propagated at the restored sites. In order to prevent human disturbance of the restored sites, a CCTV monitoring system powered by a solar panel was installed after the restoration. In addition, a human surveillance system is operated by national park rangers with local residents.