• 한국농공학회논문집
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• 제61권3호
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• pp.1-14
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• 2019

North Korea has frequently suffered from extreme agricultural crop droughts, which have led to food shortages, according to the Food and Agriculture Organization (FAO). The increasing frequency of extreme droughts, due to global warming and climate change, has increased the importance of enhancing the national capacity for drought management. Historically, a meteorological drought index based on data collected from weather stations has been widely used. But it has limitations in terms of the distribution of weather stations and the spatial pattern of drought impacts. Satellite-based data can be obtained with the same accuracy and at regular intervals, and is useful for long-term change analysis and environmental monitoring and wide area access in time and space. The Evaporative Stress Index (ESI), a satellite-based drought index using the ratio of potential and actual evaporation, is being used to detect drought response as a index of the droughts occurring rapidly over short periods of time. It is more accurate and provides faster analysis of drought conditions compared to the Standardized Precipitation Index (SPI), and the Palmer Drought Severity Index (PDSI). In this study, we analyze drought events during 2015-2017 in North Korea using the ESI satellite-based drought index to determine drought response by comparing with it with the SPI and SPEI drought indices.

• 한국BIM학회 논문집
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• 제13권2호
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• pp.1-15
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• 2023

Since the 1960s, the Korean Peninsula, which consists of 77.4 of the country's land and mountains, has seen a surge in demand for buildings due to population concentration due to urbanization and industrialization. Since then, the development of slopes has been inevitable due to the concentration and expansion of the city's population. When building a building on a slope, it is important to set the height of the surface. In this case, the means of regulating buildings in construction-related laws, such as the building closure ratio, floor area ratio, number of floors and total floor area of buildings, have an overall effect on buildings through the height of the surface. In the Korean Building Act, the setting of the height of the ground affects the calculation of the building height limit standard and the calculation of the underground floor, and it takes a long time to calculate. Therefore, the time required for attempts to change various design plans of buildings increases. The purpose of this study is to speed up the time required to calculate the weighted average of the surface when constructing buildings on slopes. In addition, the existing calculation process allows various design attempts compared to the same time given.

• 한국조경학회지
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• 제43권4호
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• pp.98-111
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• 2015

도시개발과 기후변화로 인해 증가하는 도시침수, 지하수 고갈, 하천오염 그리고 도시 열섬 현상 등의 환경문제는 도시 물순환 회복을 통해 경감시킬 수 있다. 효과적인 물순환 회복 계획수립을 위해서는 개별 사업이나 소규모 시설에 대해 물수지 현황과 변화를 면적으로 나타낼 수 있는 지도형태의 분석틀이 필요하다. 이를 위해, 토양-식생 기반의 물수지 모델 BAGLUVA의 구조를 분석하고, BAGLUVA 모델의 수문요소와 입력자료와 관련된 우리나라 관련 연구결과에 대해 조사하였다. BAGLUVA 모델은 기후, 토지이용, 지형, 토양수문 그리고 관개 등의 5가지 부문으로 구성된다. 5가지 구성요소의 상호 연계 구조와 개별 입력데이터 그리고 지형 계수, 최대증발산 비율, 유효근권 등의 개념과 적용 방법을 비교 분석하였다. 그리고, 실제 증발산량-잠재증발산량-강수량 간의 관계를 매개하는 Bagrov 계수의 산정 방식을 나타내었다. 면적단위의 토지이용별 물순환지도(Hydrotope Map)를 통해, 임의의 소규모 지역 물수지 현황을 효과적으로 파악할 수 있다. 그리고, 물순환 보전 및 관리를 위한 분산형 빗물관리, 저영향개발(LID) 시설의 계획 설계 상의 목표량 설정을 공정하고 용이하게 수행할 수 있다. 또한, 수자원 관리를 조경 및 도시계획에 통합시키는 유용한 도구이다.

• 한국토양비료학회지
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• 제48권6호
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• pp.736-743
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• 2015

Organic matter plays important roles in soil ecosystem in terms of carbon and nitrogen cycles. Due to recent concerns on climate change, carbon sequestration in agricultural land has become one of the most interesting and debating issues. It is necessary to understand behavior of soil carbon for evaluating decomposition or sequestration of organic matter and analyzing potential carbon decomposition pattern about the kinds of organic matter sources to cope with well. In order to evaluate decomposition of soil carbon according to organic material during cultivating rice in paddy field, we treated organic material such as hairy vetch, rice straw, oil cake fertilizer, and manure compost at $50{\times}50{\times}20cm$ blocks made of wood board, and analyzed carbon contents of fulvic acid and humic acid fraction, and total carbon periodically in 2013 and 2014. Soil sampling was conducted on monthly basis. Four Kinds of organic matter were mixed with soil in treatment plots on 2 weeks before transplanting of rice. The treatment of animal compost showed the highest changes of total carbon, which showed $7.9gkg^{-1}$ in May 2013 to $11.6gkg^{-1}$ in October 2014. Fulvic acid fraction which is considered to easily decompose ranged from 1 to $2gkg^{-1}$. Humic acid fraction was changed between 1 to $3gkg^{-1}$ in all treatments until organic material had been applied in 2014. From May to August in the second year, the contents of humic acid fraction increased to about $4gkg^{-1}$. The average of humic fraction carbon at treatments of animal compost was recorded highest among treatments during two years, $2.1gkg^{-1}$. The treatment of animal compost has showed the lowest ratio of fulvic acid fraction, humic acid fraction compared with other treatments. The average ratio of fulvic fraction carbon in soil ranged from 16 to 20%, and humic fraction carbon ranged from 19 to 22%. In conclusion, animal compost including wood as bulking agent is superior in sequestrating carbon at agricultural land to other kinds of raw plant residue.

• 한국조경학회지
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• 제39권6호
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• pp.1-11
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• 2011

본 연구는 도시용도지역제 시스템 개선을 통해 민간주도형 공원확보 방안을 마련하고, 동시에 도시공원 주변부를 활성화시키기 위한 새로운 전략으로서 랜드스케이프 어바니즘의 이론을 토대로 도시용도지역제에 공원복합용도지구라는 새로운 용도지구 도입을 모색하기 위한 목적으로 수행되었다. 본 연구는 도시계획가, 조경가 등 관련 전문가들을 대상으로 공원복합용도지구의 모형, 공원과 용도복합의 유형, 공원 대 도시용도의 공간크기 비율 등에 대한 선호도를 분석함으로써 공원복합용도 도입의 타당성을 일차적으로 검증하고 있다. 연구의 목적을 달성하기 위해 서울시청 공무원, 서울시정개발연구원의 연구원, 엔지니어링 회사의 도시계획, 조경관련 부서에 근무하는 도시계획가, 조경가 등 전문가를 대상으로 설문조사를 실시하였고, 연구의 결과 다음과 같은 결론을 얻을 수 있었다. 첫째, 도시계획가, 조경가 등 전문분야 간, 공무원과 연구원, 엔지니어들 간 상호이견 없이 이들 전문가들의 79.3%가 공원복합용도지구를 선호하는 것으로 분석되었다. 이것은 공원복합용도지구 모형의 도입 가능성을 제시한 결과라고 사료된다. 둘째, 공원복합용도 지구 모형에 대한 주요 선호 이유는 도시공원 확보 및 접근성 증대, 자연재해 예방 등 환경적 효과 증진을 가장 중요하게 생각하는 이유로 나타났다. 셋째, 공원복합용도지구 모형에 대한 비선호 이유는 현행 도시계획 및 도시개발 관련 제도상 불가, 공원복합용도지구에 대한 이해 부족 등이 주된 이유로 나타남으로써 관련 제도개선의 필요성을 제기하였다. 넷째, 도시공원 및 녹지 주변부에 도시적 용도가 공원과 복합화 될 경우, 모든 경우의 용도복합 유형에 대해 보통 이상으로 선호하는 것으로 나타났다. 그 중에서 가장 선호하는 공원복합유형은 공원과 문화용도의 복합인 것으로 나타났으며 특히, 문화용도는 공원과 복합화 되는 주거, 업무, 상업, 교육(연구)등 다른 어떤 유형의 용도와 복합화 되어도 선호도가 높은 경향을 보였다. 다섯째, 공원과 복합화 되는 용도복합의 수가 4개 이상이 될 경우에는 복합화에 대한 선호도가 상대적으로 낮아지는 것으로 나타나고 있어서 공원복합용도의 경우에는 공원을 포함하여 4개 이하로 복합화 되는 것이 바람직한 것으로 사료되었다. 여섯째, 공원복합용도지구 모형에 있어서 공원과 다른 도시적 용도와의 공간크기 비율은 60% 대 40%의 비율에 대해 평균 70%에서 90% 수준으로 선호하는 것으로 나타남으로써, 이 비율을 기준으로 공원 대 도시용도와의 공간크기 비율로 책정하는 것이 바람직한 것으로 사료되었다. 이상의 결과에서 공원복합용도지구 모형에 대한 타당성 제시와 함께 향후, 공원복합용도지구제를 도입할 경우에는 이 지구의 지정 범위와 방법, 지구단위계획 관련기준, 각종 도시개발 관련 지표등과 관련하여, 국토의 계획 및 이용에 관한 법률과 건축법 등 관련 제도개선에 대한 후속 연구가 있어야 할 것으로 사료되었다.

• 한국농림기상학회지
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• 제15권4호
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• pp.282-290
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• 2013

대기와 지표면을 구성하고 있는 토양 및 식생은 생물리학적/생지화학적인 과정을 통해 서로 상호작용을 한다. 이러한 과정을 모의하기 위해 지표모델과 작물 생육모델이 사용되고 있다. 지표모델인 Noah MP 모델과 작물생육모델인 CERES-Rice 모델을 비교하기 위해 해남 플럭스 관측소 인근 지역에서 작물의 생육과 증발산량을 모의하였다. 플럭스 관측자료가 수집된 2003년부터 2012년까지 해남 플럭스 관측소의 주요 식생인 벼를 대상으로 생육과 증발산량을 모의되었다. Noah MP 모델은 단순한 식생 모의 과정으로 인해 개화기를 전후로 하는 벼의 LAI 변화양상을 정확하게 반영하지 못하였다. 벼의 생체중 예측에 있어서도 실제 관측될 수 있는 생체중보다 대략 10분의 1 수준에 해당하는 생체중이 모의되었다. 증발산량 모의의 경우에도, CERES-Rice 모델의 모의값보다 약 21%에 해당하는 증발산량을 모의하였다. 반면, CERES-Rice 모델의 경우 LAI의 변화와 생체중 모의 값은 실제의 벼 생육 양상과 유사할 것으로 추정되었다. 또한, 증발산량의 경우에도 해남 플럭스 관측소에서 측정된 값과 비교하였을 때 Noah-MP모델의 모의값이 CERES-Rice 모델의 모의값에 비해 RMSE 값이 1.8배 높았다. Noah MP 모델이 보이는 높은 오차값들은 Noah MP모델이 논의 지표상태를 적절히 반영하지 못하였기 때문으로 사료되었고, 특히 과소추정된 생체중을 보정하여 증발산량을 예측할 경우 오차를 30%까지 줄일 수 있을 것으로 보인다. 따라서, Noah MP 모델에 논에서의 지표 특성을 반영할 수 있다면 보다 정확한 물질순환과 에너지 교환을 예측할 수 있을 것으로 사료된다.

• 상하수도학회지
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• 제25권3호
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• pp.407-417
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• 2011

Nowadays, the high land use, mainly used for urbanization, is affecting runoff loads of non-point pollutants to increase. According to this fact, increasing runoff loads seems like to appear that it contributes to high ratio of pollution loads in the whole the pollution loads and that this non-point source is the main cause of water becoming worse quality. Especially, concentrated pollutants on the impermeable roads run off to the public water bodies. Also the coefficient of runoff from roads is high with a fast velocity of runoff, which ends up with consequence that a lot of pollutants runoff happens when it is raining. Therefore it is very important project to evaluate the quantity of pollutant loads. In this study, I computed the pollutant loadings depending on time and rainfall to analyze characteristics of runoff while first flush storm water and evaluated the runoff time while first flush storm water and rainfall based on the change in curves on the graph. I also computed contribution ratio to identify its impact on water quality of stream. I realized that the management and treatment of first flush storm water effluents is very important for the management of road's non-point source pollutants because runoff loads of non-point source pollution are over the 80% of whole loads of stream. Also according to the evaluation of runoff loads of first flush storm water for SS, run off time was shown under the 30 minute and rainfall was shown under the 5mm which is less than 20% of whole rainfall. These are under 5mm which is regarded amount of first flush storm water by the Ministry of Environment and it is judged to be because run off by rainfall is very fast on impermeable roads. Also, run off time and rainfall of BOD is higher than SS. Therefore I realized that the management of non-point source should be managed and done differently depending on each material. Finally, the contribution ratio of pollutants loads by rainfall-runoff was shown SS 12.7%, BOD 12.7%, COD 15.9%, T-N 4.9%, T-P 8.9%, however, the pollutants loads flowing into the steam was shown 4.4%. This represents that the concentration of non-point pollutants is relatively higher and we should find the methodical management and should be concerned about non-point source for improvement on water quality of streams.

• 한국대기환경학회지
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• 제33권6호
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• pp.570-582
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• 2017

In recent years, national and local government's air quality management and climate change adaptation policy has been significantly strengthened. The measures in the two policies may be in a relationship of trade-off or synergy to each other. Greenhouse gases and air pollutants are mostly emitted from the same sources of using considerable amounts of fossil fuels. Co-benefits, in which either measure has a positive effect on the other, may be maximized by reducing the social costs and by consolidating the objectives of the various policies. In this study, the co-benefits were examined by empirically analyzing the effects of air pollutants and greenhouse gas emission reduction, social cost, and cost effectiveness between the two policies. Of the total 80 projects, the next 12 projects generated co-benefits. They are 1) extend restriction area of solid fuel use, 2) expand subsidy of low-$NO_x$ burner, 3) supply hybrid-vehicles, 4) supply electric-vehicles, 5) supply hydrogen fuel cell vehicles, 6) engine retrofit, 7) scrappage of old car, 8) low emission zone, 9) transportation demand management, 10) supply land-based electric of ship, 11) switching anthracite to clean fuel in private sector, 12) expand regional combined-energy supply. The benefits of air pollutants and greenhouse gas-related measures were an annual average of KRW 2,705.4 billion. The social benefits of the transportation demand management were the highest at an annual average of KRW 890.7 billion, and followed by scrappage of old cars and expand regional combined-energy supply. When the social benefits and the annual investment budgets are compared, the cost effectiveness ratio is estimated to be about 3.8. Overall, the reduction of air pollutants caused by the air quality management policy of Gyeonggi-do resulted in an annual average of KRW 4,790.2 billion. In the point sources management sector, the added value of $CO_2$ reduction increased by 4.8% to KRW 1,062.8 billion, while the mobile sources management sector increased by 3.6% to KRW 3,414.1 billion. If social benefits from $CO_2$ reduction are added, the annual average will increase by 7.2% to KRW 5,135.4 billion. The urban and energy management sectors have shown that social benefits increase more than twice as much as the benefits of $CO_2$ reduction. This result implies that more intensive promotion of these measures are needed. This study has significance in that it presents the results of the empirical analysis of the co-benefits generated between the similar policies in the air quality management and the climate change policy which are currently being promoted in Gyeonggi-do. This study suggested that the method of analyzing the policy effect among the main policies in the climate atmospheric policy is established and the effectiveness and priority of the major policies can be evaluated through the policy correlation analysis based on the co-benefits. It is expected that it could be a basis for evaluation the efficiency of the climate change adaptation and air quality management policies implemented by the national and local governments in the future.

• 자원ㆍ환경경제연구
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• 제23권1호
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• pp.21-42
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• 2014

본 연구에서는 기후변화에 따른 해수면 상승이 우리나라 동해안 및 남해안 일대에 미치는 경제적 영향과 이를 방어하기 위한 최적 해안 방어비율을 광역시 도별로 분석하였다. 이를 위하여 FUND(The Climate Framework for Uncertainty, Negotiation and Distribution) 모형에 우리나라에 적합한 지표들을 적용하여 분석하였다. 해당 광역시 도의 면적 대비 예상 범람 지역 비율을 분석한 결과를 보면 광역시 도별로 지리적 차이가 있어 부산광역시는 시나리오에 따라 3.19% 내외로 상대적으로 높은 범람 비율로 추정되었으나 강원도는 0.1% 내외로 낮게 추정되었다. 경제적 피해비용도 광역시 도별로 차이가 있어 경제활동이 상대적으로 활발한 부산광역시, 울산광역시 및 경상남도에서의 경제적 피해비용은 매우 높게 나타났다. 그러나 최적 해안 방어비율 추정 결과를 보면 해안선의 길이가 짧고 경제적 피해비용이 큰 부산광역시와 울산 광역시는 각각 98% 내외, 92% 내외로 높게 추정되었고 경제적 피해 규모는 상대적으로 크나 해안 방어비용 또한 높게 추정된 경상남도에서는 최적해안 방어비율이 78%~79%로 추정되었다. 이에 반하여 강원도의 경우에는 경제적 피해 규모가 작아 최적 해안 방어비율이 시나리오별로 43% 내외로 추정되었다.

• Journal of the Korean Wood Science and Technology
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• 제2권4호
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• pp.4-14
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• 1974

The total forest land area in Korea accounts for some 67 percent of the nation's land total. Its productivity, however, is very low. Consequently, forest production accounts for only about 2 percent of the gross national product and a minor proportion of no more than about 5 percent versus primary industry. In this case, however, only the direct income from forestry is taken into account, making no reference to the forestry output induced by other industrial sectors. The value added Or the induced forestry output in manufacturing the primary wood products into higher quality products, makes a larger contribution to the economy than direct contribution. So, this author has tried to analyze the structure of forestry and compute the repercussion effect and the induced output of primary forest products when utilized by other industries for their raw materials, Hsing the input-output table and attached tables for 1963 and 1966 issued by the Bank of Korea. 1. Analysis of forestry structure A. Changes in total output Durng the nine-year period, 1961-1969, the real gross national product in Korea increased 2.1 times, while that of primary industries went up about 1. 4 times. Forestry which was valued at 9,380 million won in 1961, was picked up about 2. 1 times to 20, 120 million won in 1969. The rate of the forestry income in the GNP, accordingly, was no more than 1.5 percent both in 1961 and 1962, whereas its rate in primary industries increased 3.5 to 5.4 percent. Such increase in forestry income is attributable to increased forest production and rise in timber prices. The rate of forestry income, nonetheless, was on the decrease on a gradual basis. B. Changes in input coefficient The input coefficient which indicates the inputs of the forest products into other sectors were up in general in 1966 over 1963. It is noted that the input coefficient indicating the amount of forest products supplied to such industries closely related with forestry as lumber and plywood, and wood products and furniture, showed a downward trend for the period 1963-1966. On the other hand, the forest input into other sectors was generally on the increase. Meanwhile, the input coefficient representing the yolume of the forest products supplied to the forestry sector itself showed an upward tendency, which meant more and more decrease in input from other sectors. Generally speaking, in direct proportion to the higher input coefficient in any industrial sector, the reinput coefficient which denotes the use of its products by the same sector becomes higher and higher. C. Changes in ratio of intermediate input The intermediate input ratio showing the dependency on raw materials went up to 15.43 percent m 1966 from 11. 37 percent in 1963. The dependency of forestry on raw materials was no more than 15.43 percent, accounting for a high 83.57 percent of value added. If the intermediate input ratio increases in any given sector, the input coefficient which represents the fe-use of its products by the same sector becomes large. D. Changes in the ratio of intermediate demand The ratio of the intermediate demand represents the characteristics of the intermediary production in each industry, the intermediate demand ratio in forestry which accunted for 69.7 percent in 1963 went up to 75.2 percent in 1966. In other words, forestry is a remarkable industry in that there is characteristics of the intermediary production. E. Changes in import coefficient The import coefficient which denotes the relation between the production activities and imports, recorded at 4.4 percent in 1963, decreased to 2.4 percent in 1966. The ratio of import to total output is not so high. F. Changes in market composition of imported goods One of the major imported goods in the forestry sector is lumber. The import value increased by 60 percent to 667 million won in 1966 from 407 million won in 1963. The sales of imported forest products to two major outlets-lumber and plywood, and wood products and furniture-increased to 343 million won and 31 million won in 1966 from 240million won and 30 million won in 1963 respectively. On the other hand, imported goods valued at 66 million won were sold to the paper products sector in 1963; however, no supply to this sector was recorded in 1963. Besides these major markets, primary industries such as the fishery, coal and agriculture sectors purchase materials from forestry. 2. Analysis of repercussion effect on production The repercussion effect of final demand in any given sector upon the expansion of the production of other sectors was analyzed, using the inverse matrix coefficient tables attached to the the I.O. Table. A. Changes in intra-sector transaction value of inverse matrix coefficient. The intra-sector transaction value of an inverse matrix coefficient represents the extent of an induced increase in the production of self-support products of the same sector, when it is generated directly and indirectly by one unit of final demand in any given sector. The intra-sector transaction value of the forestry sector rose from 1.04 in 1963 to 1, 11 in 1966. It may well be said, therefore, that forestry induces much more self-supporting products in the production of one unit of final demand for forest products. B. Changes in column total of inverse matrix coefficient It should be noted that the column total indicates the degree of effect of the output of the corresponding and related sectors generated by one unit of final demand in each sector. No changes in the column total of the forestry sector were recorded between the 1963 and 1966 figures, both being the same 1. 19. C. Changes in difference between column total and intra-sector transaction amount. The difference between the column total and intra-sector transaction amount by sector reveals the extent of effect of output of related industrial sector induced indirectly by one unit of final demand in corresponding sector. This change in forestry dropped remarkable to 0.08 in 1966 from 0.15 in 1963. Accordingly, the effect of inducement of indirect output of other forestry-related sectors has decreased; this is a really natural phenomenon, as compared with an increasing input coefficient generated by the re-use of forest products by the forestry sector. 3. Induced output of forestry A. Forest products, wood in particular, are supplied to other industries as their raw materials, increasng their value added. In this connection the primary dependency rate on forestry for 1963 and 1966 was compared, i. e., an increase or decrease in each sector, from 7.71 percent in 1963 to 11.91 percent in 1966 in agriculture, 10.32 to 6.11 in fishery, 16.24 to 19.90 in mining, 0.76 to 0.70 in the manufacturing sector and 2.79 to 4.77 percent in the construction sector. Generally speaking, on the average the dependency on forestry during the period 1963-1966 increased from 5.92 percent to 8.03 percent. Accordingly, it may easily be known that the primary forestry output induced by primary and secondary industries increased from 16, 109 million won in 1963 to 48, 842 million won in 1966. B. The forest products are supplied to other industries as their raw materials. The products are processed further into higher quality products. thus indirectly increasing the value of the forest products. The ratio of the increased value added or the secondary dependency on forestry for 1963 and 1966 showed an increase or decrease, from 5.98 percent to 7.87 percent in agriculture, 9.06 to 5.74 in fishery, 13.56 to 15.81 in mining, 0.68 to 0.61 in the manufacturing sector and 2.71 to 4.54 in the construction sector. The average ratio in this connection increased from 4.69 percent to 5.60 percent. In the meantime, the secondary forestry output induced by primary and secondary industries rose from 12,779 million Wall in 1963 to 34,084 million won in 1966. C. The dependency of tertiary industries on forestry showed very minor ratios of 0.46 percent and 0.04 percent in 1963 and 1966 respectively. The forestry output induced by tertiary industry also decreased from 685 million won to 123 million won during the same period. D. Generally speaking, the ratio of dependency on forestry increased from 17.68 percent in 1963 to 24.28 percent in 1966 in primary industries, from 4.69 percent to 5.70 percent in secondary industries, while, as mentioned above, the ratio in the case of tertiary industry decreased from 0.46 to 0.04 percent during the period 1963-66. The mining industry reveals the heaviest rate of dependency on forestry with 29.80 percent in 1963 and 35.71 percent in 1966. As it result, the direct forestry income, valued at 8,172 million won in 1963, shot up to 22,724 million won in 1966. Its composition ratio lo the national income rose from 1.9 percent in 1963 to 2.3 per cent in 1966. If the induced outcome is taken into account, the total forestry production which was estimated at 37,744 million won in 1963 picked up to 105,773 million won in 1966, about 4.5 times its direct income. It is further noted that the ratio of the gross forestry product to the gross national product. rose significantly from 8.8 percent in 1963 to 10.7 percent in 1966. E. In computing the above mentioned ratio not taken into consideration were such intangible, indirect effects as the drought and flood prevention, check of soil run-off, watershed and land conservation, improvement of the people's recreational and emotional living, and maintenance and increase in the national health and sanitation. F. In conclusion, I would like to emphasize that the forestry sector exercices an important effect upon the national economy and that the effect of induced forestry output is greater than its direct income.