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Analysis of Environmental Sustainability in South Korean Inland Windfarms (한국 육상풍력발전사업의 환경적 지속가능성 평가 연구 - 58개 환경영향평가서 사례에 대한 정량적 분석 -)

  • Jeong, Eunhae
    • Journal of Environmental Impact Assessment
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    • v.31 no.1
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    • pp.47-62
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    • 2022
  • Wind power has been rapidly growing over last decade in the world as well as in South Korea as a feasible renewable energy source. Providing sustainable energy to all while securing environmental sustainability requires evidence based policy making and innovative solutions. Through analysis of 58 cases of South Korean Environmental Impact Assessment (EIA) Report, this paper seeks to identify answers to the following two questions. What are the key characteristics for inland windfarm? Is there a way of measuring environmental sustainability to compare each location to reduce negative environmental impact? Variables related to environmental sustainability of each windfarm case were collected from EIA report and the factor analysis of environmental variables was conducted to calculate the weight for each variable to build environmental sustainability index (ESI) to provide as evidence-based tools for decision making on the location of inland windfarm. 58 cases were categorized as three types 1) Mountain type 2) Ranch Type and 3) Coastal Type depending on their height and degree of naturalness. For analytical research, first, it was successfully calculated environmental sustainability of each windfarm case ranging from 1.04 (#33, Ranch type) to -1.44 (#55, Mountain type). Second, the analysis results showed that ranch type is most environmentally sustainable (Average ESI = 0.4551), followed by coastal type (Ave ESI = 0.3712) and lastly mountain type (Average ESI = -0.3457). These findings are consistent with the previous researches on inland windfarms and provides substantive policy implication on the renewable energy policies.

A Parametric Study for Jointed Rock Slope Using FEM (절리 암반사면에서의 인자효과에 의한 유한요소 해석의 타당성 검토)

  • Lee, Jin-A;Chung, Chang-Hee;Chun, Byung-Sik
    • Journal of the Korean Geotechnical Society
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    • v.23 no.6
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    • pp.97-102
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    • 2007
  • Though the stability analysis of soil slopes widely employs the limit equilibrium method, the study on the jointed rock slopes must consider the direction of joint and the characteristics of Joint at the same time. This study analyzes the result of the change in the factors which show the characteristics of discontinuity and the shape factor of rock slopes, and so on, in an attempt to validate the propriety as to the interpretation of jointed rock slope stability which uses the general finite element program. First, the difference depending on the flow rules was compared, and the factor effect study was conducted. The selected independent variables included the direction of joint which displays the mechanical characteristics of discontinuity, adhesive cohesion, friction angle, the inclination and height of rock slope which reveal the shape of slope and surcharge load. And the horizontal displacement was numerically interpreted at the 1/3 point below the slope, a dependent variable, to compare the relative degree of factor effects. The findings of study on factor effects led to the validation that the result of horizontal displacement for each factor satisfied various engineering characteristics, making it possible to be applied to stability interpretation of jointed rock slope. A modelling is possible, which considers the application of the result of real geotechnical surveys & laboratory studies and the non-linear characteristics when designing the rock slope. In addition, the stress change which may result from the natural disaster, such as precipitation, and the construction, can be expressed. Furthermore, as the complicated rock condition and the ground supporting effect can be considered through FEM, it is considered to be very useful in making an engineering decision on the cut-slope, reinforcement and so on.

Development of Diameter Distribution Change and Site Index in a Stand of Robinia pseudoacacia, a Major Honey Plant (꿀샘식물 아까시나무의 지위지수 도출 및 직경분포 변화)

  • Kim, Sora;Song, Jungeun;Park, Chunhee;Min, Suhui;Hong, Sunghee;Yun, Junhyuk;Son, Yeongmo
    • Journal of Korean Society of Forest Science
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    • v.111 no.2
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    • pp.311-318
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    • 2022
  • We conducted this study to derive the site index, which is a criterion for the planting of Robinia pseudoacacia, a honey plant, and to investigate the diameter distribution change by derived site index. We applied the Chapman-Richards equation model to estimate the site index of the Robinia pseudoacacia stand. The site index was distributed within the range of 16-22 when the base age was 30 years. The fitness index of the site index estimation model was low, but we judged that there was no problem in the application because the residual distribution of the equation had not shifted to one side. We used the Weibull diameter distribution function to determine the diameter distribution of the Robinia pseudoacacia stand by site index. We used the mean diameter and the dominant tree height as independent variables to present the diameter distribution, and our analysis procedure was to estimate and recover the parameters of the Weibull diameter distribution function. We used the mean diameter and the dominant tree height of the Robinia pseudoacacia stand to show distribution by diameter class, and the fitness index for dbh distribution estimation was about 80.5%. As a result of schematizing the diameter distribution by site indices as a 30-year-old, we found that the higher the site index, the more the curve of the diameter distribution moved to the right. This suggests that if the plantation were to be established in a high site index stand, considering the suitable trees on the site, the growth of Robinia pseudoacacia woul d become active, and not onl y the production of wood but al so the production of honey would increase. We therefore anticipate that the site index classification table and curve of this Robinia pseudoacacia stand will become the standard for decision making in the plantation and management of this tree.

Research on Proper Dietary Recommendations for Korea (한국인(韓國人)의 균형식(均衡食) 권장에 관한 연구(硏究) -한국인(韓國人)의 식생활(食生活)의 추이(해방후 30년간)-)

  • Lee, Ki-Yull;Leekim, Yang-Cha
    • Journal of Nutrition and Health
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    • v.10 no.2
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    • pp.59-70
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    • 1977
  • This study was designed to evaluate the changes and improvements in the Korean diet during the last thirty years (since independence in 1945), and to make recommendations for the improvement of their nutritional status, consequently contributing to the physical and mental welfare of the Korean people. The results and recommendations are as follows: 1. The total calorie and carbohydrate intake decreased by $8{\sim}12%$ in the 1970's, as compared with the 1940's and the 1950's. 2. The intake of calcium and vitamiu A increased $30{\sim}50%$ and $20{\sim}60%$ respectively in the 1960's and 1970's as compared with the 1940,s. But this intake level is still lower than the RDA values. 3. The vitamin C intake was somewhat higher in the mountainous and farming areas than in urban areas. 4. In the 1970's, the decrease of untriend intake due to seasonal variation was marked especially for protein, niacin, vitamin $B_1$, and vitamin C. 5. The consumption of protein foods (meats and legumes) increased in an amount of $15{\sim}36g$ per day. There was a marked increase in the intake of meat in farming areas and of milk in urban areas in the 1970's. This increased intake of animal proteins is a very desirable dietary change. 6. The cereal consumption was lowest in urban areal, but there was a general decrease in the intake of the cereal group in the entire area in the 1970's. For the farmers, the intake of cereal food decreased most, from 750 g to 576 g, but cereals still composed a high proportion of the entire diet. 7. Fruits and vegetables showed the highest intake for the urban people, as expected. For the whole area, this food group showed an increase of 8.7% in the 1970's, as compared with the 1960's. 8. The gradual ihcrease in the intake of the fats and oil group was a desirable dietary change. but the absolute amount was too low. 9. A 7% increase in height and a 9% incrrase in weight for growing children and adolescents was observed in the 1970's as compared with the 1940's, but several kinds of deficiency diseases, such as nutritional anemia and dental caries were still apparent in many areas. 10. To improve cur food life and to cope with food shortages faced in Korea, an efficient and nationwide nutrition education program should be implemented. This would maximize efficiency of intake from the limited food sources for a balanced diet. 11. As it is of utmost importance to provide growing children with a desirable physical, sccial mental, and especially nutritional environment, a well-planned and organized school feeding program should be practiced widely and efficiently. 12. Young mothers and pregnant women should be educated on the importance of their children's nutrition, especially for the critical fetal and infancy periods. 13. More thorough and continuous nutritional survey studies on the changes in dietary patterns for the entire nation should be pursued, evaluated and documented. This would Provide a good information guide for future nutritional study programs. 14. It is the nutritionistist's strong desire that national leaders, especially decision makers recognize the fact that improvement of the nutritional status of the People is one of the most economic and preventative ways of improving their physical and mental health. This is closely related to the economic development and strength of the nation.

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Prioritization of Species Selection Criteria for Urban Fine Dust Reduction Planting (도시 미세먼지 저감 식재를 위한 수종 선정 기준의 우선순위 도출)

  • Cho, Dong-Gil
    • Korean Journal of Environment and Ecology
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    • v.33 no.4
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    • pp.472-480
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    • 2019
  • Selection of the plant material for planting to reduce fine dust should comprehensively consider the visual characteristics, such as the shape and texture of the plant leaves and form of bark, which affect the adsorption function of the plant. However, previous studies on reduction of fine dust through plants have focused on the absorption function rather than the adsorption function of plants and on foliage plants, which are indoor plants, rather than the outdoor plants. In particular, the criterion for selection of fine dust reduction species is not specific, so research on the selection criteria for plant materials for fine dust reduction in urban areas is needed. The purpose of this study is to identify the priorities of eight indicators that affect the fine dust reduction by using the fuzzy multi-criteria decision-making model (MCDM) and establish the tree selection criteria for the urban planting to reduce fine dust. For the purpose, we conducted a questionnaire survey of those who majored in fine dust-related academic fields and those with experience of researching fine dust. A result of the survey showed that the area of leaf and the tree species received the highest score as the factors that affect the fine dust reduction. They were followed by the surface roughness of leaves, tree height, growth rate, complexity of leaves, edge shape of leaves, and bark feature in that order. When selecting the species that have leaves with the coarse surface, it is better to select the trees with wooly, glossy, and waxy layers on the leaves. When considering the shape of the leaves, it is better to select the two-type or three-type leaves and palm-shaped leaves than the single-type leaves and to select the serrated leaves than the smooth edged leaves to increase the surface area for adsorbing fine dust in the air on the surface of the leaves. When considering the characteristics of the bark, it is better to select trees that have cork layers or show or are likely to show the bark loosening or cracks than to select those with lenticel or patterned barks. This study is significant in that it presents the priorities of the selection criteria of plant material based on the visual characteristics that affect the adsorption of fine dust for the planning of planting to reduce fine dust in the urban area. The results of this study can be used as basic data for the selection of trees for plantation planning in the urban area.

Thermal Behavior and Leaf Temperature in a High Pressure Sodium Lamp Supplemented Greenhouse (고압나트륨등 보광 온실의 열적 거동 및 엽온 분석)

  • Seungri Yoon;Jin Hyun Kim;Minju Shin;Dongpil Kim;Ji Wong Bang;Ho Jeong Jeong;Tae In Ahn
    • Journal of Bio-Environment Control
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    • v.32 no.1
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    • pp.48-56
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    • 2023
  • High-pressure sodium (HPS) lamps have been widely used as a useful supplemental light source to emit sufficient photosynthetically active radiation and provide a radiant heat, which contribute the heat requirement in greenhouses. The objective of this study to analyze the thermal characteristics of HPS lamp and thermal behavior in supplemented greenhouse, and evaluate the performance of a horizontal leaf temperature of sweet pepper plants using computational fluid dynamics (CFD) simulation. We simulated horizontal leaf temperature on upper canopy according to three growth stage scenarios, which represented 1.0, 1.6, and 2.2 plant height, respectively. We also measured vertical leaf and air temperature accompanied by heat generation of HPS lamps. There was large leaf to air temperature differential due to non-uniformity in temperature. In our numerical calculation, thermal energy of HPS lamps contributed of 50.1% the total heat requirement on Dec. 2022. The CFD model was validated by comparing measured and simulated data at the same operating condition. Mean absolute error and root mean square error were below 0.5, which means the CFD simulation values were highly accurate. Our result about vertical leaf and air temperature can be used in decision making for efficient thermal energy management and crop growth.

Development and assessment of pre-release discharge technology for response to flood on deteriorated reservoirs dealing with abnormal weather events (이상기후대비 노후저수지 홍수 대응을 위한 사전방류 기술개발 및 평가)

  • Moon, Soojin;Jeong, Changsam;Choi, Byounghan;Kim, Seungwook;Jang, Daewon
    • Journal of Korea Water Resources Association
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    • v.56 no.11
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    • pp.775-784
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    • 2023
  • With the increasing trend of extreme rainfall that exceeds the design frequency of man-made structures due to extreme weather, it is necessary to review the safety of agricultural reservoirs designed in the past. However, there are no local government-managed reservoirs (13,685) that can be discharged in an emergency, except for reservoirs over a certain size under the jurisdiction of the Korea Rural Affairs Corporation. In this case, it is important to quickly deploy a mobile siphon to the site for preliminary discharge, and this study evaluated the applicability of a mobile siphon with a diameter of 200 mm, a minimum water level difference of 6 m, 420 (m2/h), and 10,000 (m2/day), which can perform both preliminary and emergency discharge functions, to the Yugum Reservoir in Gyeongju City. The test bed, Yugum Reservoir, is a facility that was completed in 1945 and has been in use for about 78 years. According to the hydrological stability analysis, the lowest height of the current dam crest section is 27.15 (EL.m), which is 0.29m lower than the reviewed flood level of 27.44 (EL.m), indicating that there is a possibility of lunar flow through the embankment, and the headroom is insufficient by 1.72 m, so it was reviewed as not securing hydrological safety. The water level-volume curve was arbitrarily derived because it was difficult to clearly establish the water level-flow relationship curve of the reservoir since the water level-flow measurement was not carried out regularly, and based on the derived curve, the algorithm for operating small and medium-sized old reservoirs was developed to consider the pre-discharge time, the amount of spillway discharge, and to predict the reservoir lunar flow time according to the flood volume by frequency, thereby securing evacuation time in advance and reducing the risk of collapse. Based on one row of 200 mm diameter mobile siphons, the optimal pre-discharge time to secure evacuation time (about 1 hour) while maintaining 80% of the upper limit water level (about 30,000 m2) during a 30-year flood was analyzed to be 12 hours earlier. If the pre-discharge technology utilizing siphons for small and medium-sized old reservoirs and the algorithm for reservoir operation are implemented in advance in case of abnormal weather and the decision-making of managers is supported, it is possible to secure the safety of residents in the risk area of reservoir collapse, resolve the anxiety of residents through the establishment of a support system for evacuating residents, and reduce risk factors by providing risk avoidance measures in the event of a reservoir risk situation.

The detection of collapsible airways contributing to airflow limitation (기류 제한에 영향을 미치는 허탈성 기도의 분석)

  • Kim, Yun Seong;Park, Byung Gyu;Lee, Kyong In;Son, Seok Man;Lee, Hyo Jin;Lee, Min Ki;Son, Choon Hee;Park, Soon Kew
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.4
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    • pp.558-570
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    • 1996
  • Background : The detection of Collapsible airways has important therapeutic implications in chronic airway disease and bronchial asthma. The distinction of a purely collapsible airways disease from that of asthma is important because the treatment of the dormer may include the use of pursed lip breathing or nasal positive pressure ventilation whereas in the latter, pharmacologic approaches are used. One form of irreversible airflow limitation is collapsible airways, which has been shown to be a Component of asthma or to emphysema, it can be assessed by the volume difference between what exits the lung as determined by a spirometer and the volume compressed as measured by the plethysmography. Method : To investigate whether volume difference between slow and forced vital Capacity(SVC-FVC) by spirometry may be used as a surrogate index of airway collapse, we examined pulmonary function parameters before and after bronchodilator agent inhalation by spirometry and body plethysmography in 20 cases of patients with evidence of airflow limitation(chronic obstructive pulmonary disease 12 cases, stable bronchial asthma 7 cases, combined chronic obstructive pulmonary disease with asthma 1 case) and 20 cases of normal subjects without evidence of airflow limitation referred to the Pusan National University Hospital pulmonary function laboratory from January 1995 to July 1995 prospectively. Results : 1) Average and standard deviation of age, height, weight of patients with airflow limitation was $58.3{\pm}7.24$(yr), $166{\pm}8.0$(cm), $59.0{\pm}9.9$(kg) and those of normal subjects was $56.3{\pm}12.47$(yr), $165.9{\pm}6.9$(cm), $64.4{\pm}10.4$(kg), respectively. The differences of physical characteristics of both group were not significant statistically and male to female ratio was 14:6 in both groups. 2) The difference between slow vital capacity and forced vital capacity was $395{\pm}317ml$ in patients group and $154{\pm}176ml$ in normal group and there was statistically significance between two groups(p<0.05). Sensitivity and specificity were most higher when the cut-off value was 208ml. 3) After bronchodilator inhalation, reversible airway obstructions were shown in 16 cases of patients group, 7 cases of control group(p<0.05) by spirometry or body plethysmography d the differences of slow vital capacity and forced vital capacity in bronchodilator response group and nonresponse group were $300.4{\pm}306ml$, $144.7{\pm}180ml$ and this difference was statistically significant. 4) The difference between slow vital capacity and forced vital capacity before bronchodilator inhalation was correlated with airway resistance before bronchodilator(r=0.307 p=0.05), and the difference between slow vital capacity and forced vital capacity after bronchodilator was correlated with difference between slow vital capacity and forced vital capacity(r=0.559 p=0.0002), thoracic gas volume(r=0.488 p=0.002) before bronchodilator and airway resistance(r=0.583 p=0.0001), thoracic gas volume(r=0.375 p=0.0170) after bronchodilator, respectively. 5) The difference between slow vital capacity and forced vital capacity in smokers and nonsmokers was $257.5{\pm}303ml$, $277.5{\pm}276ml$, respectively and this difference did not reach statistical significance(p>0.05). Conclusion : The difference between slow vital capacity and forced vital capacity by spirometry may be useful for the detection of collapsible airway and may help decision making of therapeutic plans.

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A Study on Legal and Regulatory Improvement Direction of Aeronautical Obstacle Management System for Aviation Safety (항공안전을 위한 장애물 제한표면 관리시스템의 법·제도적 개선방향에 관한 소고)

  • Park, Dam-Yong
    • The Korean Journal of Air & Space Law and Policy
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    • v.31 no.2
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    • pp.145-176
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    • 2016
  • Aviation safety can be secured through regulations and policies of various areas and thorough execution of them on the field. Recently, for aviation safety management Korea is making efforts to prevent aviation accidents by taking various measures: such as selecting and promoting major strategic goals for each sector; establishing National Aviation Safety Program, including the Second Basic Plan for Aviation Policy; and improving aviation related legislations. Obstacle limitation surface is to be established and publicly notified to ensure safe take-off and landing as well as aviation safety during the circling of aircraft around airports. This study intends to review current aviation obstacle management system which was designed to make sure that buildings and structures do not exceed the height of obstacle limitation surface and identify its operating problems based on my field experience. Also, in this study, I would like to propose ways to improve the system in legal and regulatory aspects. Nowadays, due to the request of residents in the vicinity of airports, discussions and studies on aviational review are being actively carried out. Also, related ordinance and specific procedures will be established soon. However, in addition to this, I would like to propose the ways to improve shortcomings of current system caused by the lack of regulations and legislations for obstacle management. In order to execute obstacle limitation surface regulation, there has to be limits on constructing new buildings, causing real restriction for the residents living in the vicinity of airports on exercising their property rights. In this sense, it is regarded as a sensitive issue since a number of related civil complaints are filed and swift but accurate decision making is required. According to Aviation Act, currently airport operators are handling this task under the cooperation with local governments. Thus, administrative activities of local governments that have the authority to give permits for installation of buildings and structures are critically important. The law requires to carry out precise surveying of vast area and to report the outcome to the government every five years. However, there can be many problems, such as changes in the number of obstacles due to the error in the survey, or failure to apply for consultation with local governments on the exercise of construction permission. However, there is neither standards for allowable errors, preventive measures, nor penalty for the violation of appropriate procedures. As such, only follow-up measures can be taken. Nevertheless, once construction of a building is completed violating the obstacle limitation surface, practically it is difficult to take any measures, including the elimination of the building, because the owner of the building would have been following legal process for the construction by getting permit from the government. In order to address this problem, I believe penalty provision for the violation of Aviation Act needs to be added. Also, it is required to apply the same standards of allowable error stipulated in Building Act to precise surveying in the aviation field. Hence, I would like to propose the ways to improve current system in an effective manner.