• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.42 no.2
• /
• pp.220-227
• /
• 1997

Water deficit stress during early soybean[Glycine max (L.) Merrill] growth stage is the most important environmental factor limiting productivity. Eight soybean genotypes were grown in replicated pot under well-watered(control: near 0 bar) and drought(-5 and -10 bars) conditions. Soybean plants were subject to drought stress for 20 days at 10 days after seed emergence. Significant genotypic variation was observed for leaf area(LA) and total dry weight (TDW). At the end of water stress, LA and TDW of Hwanggeumkong and Paldalkong, which had large LA in the non-stressed control, were more sensitive to water stress than those of the other cultivars, while those of Suwon 93 with small LA were insensitive. Leaf proline and abscisic acid(ABA) contents increased after water stress. However, changes in proline and ABA contents were not consistently related to the changes in LA as affected by water stress. As the soil water potential decreased, the yield reduction of Hodgson 78 showing large decrease in LA and TDW in response to water deficit was severe when compared to that of Baegunkong with small decrease in LA and TDW. Relatively greater yield stability and higher average yield across soil water potential were observed in Baegunkong. Of specific interest was the small reduction in yield of Paldalkong in spite of its significant decrease in LA and TDW.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2012.05a
• /
• pp.439-439
• /
• 2012

본 연구의 목적은 색달하수처리장 방류수를 농업용수 및 조경용수 등으로 활용하기 위해 하수 처리수 재이용 사업 타당성을 분석하고자 한다. 색달하수처리장 하수재이용사업은 제주도의 지하수자원 보존과 수자원 이용의 고도화 및 방류수 재이용을 통한 갈수기 농업용수 보급으로 물자원(지하수)을 절약하고자 색달하수처리장을 대상으로 하수처리수를 농업용수로 공급하는 사업이다. 대상지역은 서귀포시 예래동에 위치하고 있으며, 중문관광단지가 소재한 마을로 제주관광의 중심지이다. 서귀포시의 총 인구는 153,797명이며 하수도 보급률은 77.7%이다('10 제주특별자치도 통계연보). 색달하수처리장이 위치한 예래동의 농지면적이 1,122ha이며, 밭(772.6)과 과수원(280.2) 등 제주도의 전형적인 농촌마을이다. 대상지역의 주요작물은 감귤, 무, 마늘, 양배추 등이 많이 재배된다. 제주도는 연평균 강수량이 1,832.6mm로 전국평균 1,274 mm 보다 많은 편이며, 월별 강수량은 6~8월까지 3개월 동안 연 강우량의 44%정도가 내려 여름 장마철에 집중되는 것으로 나타났다. 대상지구의 필요수량은 농업생산정비 계획설계기준에 제시된 방법을 이용하여 산정하였다. 지구내 재이용수를 공급할 관정 4개소의 총 설계 채수량은 $2,916m^3/day$, 급수면적은 125.0ha이며, 10년한발(가뭄)시 안정적인 농업용수 공급을 위하여 $4,964m^3/day$(농업용수 $3,834m^3/day$, 조경용수 $1,130m^3/day$)이 필요하다. 하수처리수 재이용을 위한 처리시설의 연간 유지관리비는 인건비, 전력비, 시설물 내구연한을 고려하여 적용 하였으며, 상수도 생산비 절감 비용과 하수재이용수 생산단가를 통한 단위 편익을 산정하면 401.5원/$m^3$ 이다. 연차별 수익으로 산정하여 비용 편익 비율(B/C Ratio)을 나타내면 1.22로 나타났다. 본 연구의 결과로부터, 대상지구의 수자원여건, 입지여건, 장래 수요, 등을 고려할 때, 제주 색달 하수처리장의 하수처리수의 농업용수재이용 사업은 타당성이 매우 높다고 할 수 있다. 그리고 특히 이 지역은 관광단지의 조경용수 수요(중문골프장 등)가 있어 용수의 유료공급이 가능하고 이를 유지관리비로 충당할 수 있어 타지역에 비해 사업의 경제성과 환경보전성이 매우 크다.

• Journal of Korea Water Resources Association
• /
• v.51 no.10
• /
• pp.839-852
• /
• 2018

The purpose of this study is to predict monthly agricultural reservoir storage by developing weather data-based Multiple Linear Regression Model (MLRM) with precipitation, maximum temperature, minimum temperature, average temperature, and average wind speed. Using Naïve-Bayes classification, total 1,559 nationwide reservoirs were classified into 30 clusters based on geomorphological specification (effective storage volume, irrigation area, watershed area, latitude, longitude and frequency of drought). For each cluster, the monthly MLRM was derived using 13 years (2002~2014) meteorological data by KMA (Korea Meteorological Administration) and reservoir storage rate data by KRC (Korea Rural Community). The MLRM for reservoir storage rate showed the determination coefficient ($R^2$) of 0.76, Nash-Sutcliffe efficiency (NSE) of 0.73, and root mean square error (RMSE) of 8.33% respectively. The MLRM was evaluated for 2 years (2015~2016) using 3 months weather forecast data of GloSea5 (GS5) by KMA. The Reservoir Drought Index (RDI) that was represented by present and normal year reservoir storage rate showed that the ROC (Receiver Operating Characteristics) average hit rate was 0.80 using observed data and 0.73 using GS5 data in the MLRM. Using the results of this study, future reservoir storage rates can be predicted and used as decision-making data on stable future agricultural water supply.

• Korean Journal of Breeding Science
• /
• v.41 no.3
• /
• pp.261-270
• /
• 2009

Oxidative stress is a major damaging factor for plants exposed to environmental stresses. In order to develop transgenic rice plants with enhanced tolerance to various environmental stresses, PsAPX1, the gene of ascorbate peroxidase isolated from Pisum sativum was expressed in chloroplast under the control of an oxidative stress inducible sweet potato peroxidase2 (SWPA2) promoter (referred to as PsAPX1 plants). PsAPX1 transgenic plants showed enhanced tolerance to various environmental stresses, such as 170 mM NaCl, UV-B, ozone, 20% PEG, and drought in compared with non-transgenic (NT) plants. These results suggest that chloroplast-targeted over-expression of PsAPX1 gene could be very useful strategy for developing transgenic rice plants with increased tolerance to environmental stresses.

• Journal of Korean Philosophical Society
• /
• v.147
• /
• pp.239-260
• /
• 2018

Is an artificial intelligence robot, a non-human beings newly emerging in the age of technology, a threat to human beings, or a mutual cooperation or ensemble with human beings? The desire to control nature through the use of the power of science and technology is manifested in the fear that humans can annihilate themselves. This study attempts to identify the problems of Cartesian epistemology underlying these questions and fears and to answer these questions based on Merleau - Ponty 's ontological ontology using the Ontology and Latour' s ontology and technological philosophy. The cogito derived from the Cartesian philosophy became the basis of the structure of dichotomous epistemology of 'subjectivity and objectivity' based on human - reason. In the human-centered world, all non-human beings were tools or controls for humans. The problem of the modern people is not only to get help from the natural scientific methods to control the nature including man, but also to think that scientific method is the only way to understand the world. In criticizing this, Merleau-Ponty shows that the body mediates between human beings and non-human beings, and provides a possible ontological basis for the ontology. Merleau - Ponty 's phenomenological methodology and ontology are newly developed by Simondon under the influence of phenomenological philosopher and phenomenology. The relationship between human beings and nonhuman beings by Simondon appears as an ensemble of human and technical objects or a mutual co - operation of human and technical objects. In particular, Latour goes a step further in Simondon and defines all the bodies living in the world as actor-network theory, denying the core concept of modernity. Merleau - Ponty 's phenomenological view can be a new possible basis for the philosophical discussion of the technological age. We will see that the problem itself can be solved by shifting modern fear to a phenomenological attitude.

• Korean Journal of Soil Science and Fertilizer
• /
• v.22 no.4
• /
• pp.285-289
• /
• 1989

Interrelationships between yields of Burley 21 variety and meteorological factors such as precipitation, duration of sunshine, and evaporation in Suweon, Chungju, Daegu, and Jeonju were investigated during the growing seasons from 1976 to 1985. Cultivation period from the 41st to the 60th day after transplanting which showed the highest transpiration by the tobacco plant was corresponding to relatively dry season in Korea from the middle of May to early of June. The meteorological factors during the middle stage of the tobacco growth, especially the 41st to the 80th day after transplanting, seemed to have higher correlation with tobacco yield, than any other periods. This result implied that the middle stage of the growth when tobacco plant consume more soil moisture by transpiration proved to be a important growth stage having a great influence upon tobacco productivity.

• Korean Journal of Soil Science and Fertilizer
• /
• v.13 no.4
• /
• pp.115-118
• /
• 1981

Effect of water potential of culture solution on photosynthesis, transpiration and water uptake was investigated using polyethylene glycol 6000. 1. Even at -0.5 bar of culture solution phothosynthesis was decreased by 20% within 1 hour. Plant in control showed 3.26% loss of initial water for 13 hours suggesting very sensitive in water uptake. 2. Relation between water potential of culture solution (${\psi}$) and water uptake amount (W) 2-year root was ${\psi}=-2.890/e^{2.796W}$ indicating that permanent wilting point will be greater than -2.89 bar. 3. Transpiration considerably decreased with the decrease of water potential and thus by 23.9% at -0.5 bar after 4 hours. 4. From the above results ginseng plant appears to have high root water potential at permanent wilting point and thus very week to water stress due to drought or high salt content in soils.

• Korean Journal of Construction Engineering and Management
• /
• v.22 no.2
• /
• pp.106-118
• /
• 2021

Global governments and initiatives have attempted and integrated various organizational efforts to implement the 17 Sustainable Development Goals (SDGs), presenting a new paradigm of sustainable development to address global issues (climate change, poverty eradication, and human rights). Recently, investment in sustainable finance has expanded to finance the attainment of goals set out in the Paris Agreement and SDGs. Non-financial factors such as environment, social responsibility, and governance (ESG) have become intangible assets that determine the future competitiveness and profitability of companies. Domestic and foreign institutional investors and asset management companies have been expanding their investments based on the ESG performance of companies. In this study, we aim to derive international standards and initiatives that require disclosure of information on corporate social responsibility activities and ESG performance and analyze construction companies' ESG activities and performance levels. The results of this study can be used as the basis to develop platforms for the construction industry ESG ecosystem and the measurement and management of intangible assets. These could ultimately contribute to overcoming the crisis in the future due to the outbreak of the COVID-19 pandemic, fostering net-zero emissions, and preventing fatal workplace accidents in the construction industry.

• Maritime Security
• /
• v.1 no.1
• /
• pp.241-271
• /
• 2020

The military technology currently receiving the most attention is the hypersonic missile. hypersonic is faster than the speed of sound or Mach 5+. The vast majority of the ballistic missiles that it inspired achieved hypersonic speeds as they fell from the sky. Rather than speed, today's renewed attention to hypersonic weapons owes to developments that enable controlled flight. These new systems have two sub-varieties: hypersonic glide vehicles and hypersonic cruise missiles. Hypersonic weapons could challenge detection and defense due to their speed, maneuverability, and low altitude of flight. The fundamental question of this study is: 'What effect will the hypersonic missile have on the maritime strategy?' It is quite prudent to analyze and predict the impact of technology in the development stage on strategy in advance. However, strategy is essential because it affect future force construction. hypersonic missiles act as a limiting factor in securing sea control. The high speed and powerful destructive power of the hypersonic missile are not only difficult to intercept, but it also causes massive ship damage at a single shot. As a result, it is analyzed that the Securing sea control will be as difficult as the capacity of sea denial will be improved geographically and qualitatively. In addition, the concept of Fortress Fleet, which was criticized for its passive strategy in the past, could be reborn in a modern era. There are maritime power projection/defence, SLOC attack/defence in exploiting sea control. The effects of hypersonic missiles on exploiting sea control could be seen as both limiting and opportunity factors.

• The Journal of the Korea Contents Association
• /
• v.21 no.2
• /
• pp.49-58
• /
• 2021

The Korean curriculum and admission system have evolved through numerous changes. Currently, the nation's college entrance rate stands at nearly 70 percent, and it is the highest among OECD members. Amid this environment, the importance of school life records is increasing among students who are interested in going to college and who have the highest percentage in the nation's education system. Happiness is not the order of grades, but I can find my future and happiness at the same time through active school life. Through the analysis system of school life records, you can find interests and career paths suitable for yourself, and analyze and supplement factors suitable for the university and department you want to go to, so that you can take a step further in successful advancement. Each item in the school records is divided into three categories to analyze the necessary and unnecessary words. By visualizing and numericalizing the analyzed data, an analysis system is established that can be supplemented in school life. An analysis system through data mining can be utilized by concisely summarizing sentences of different elements and extracting words by applying the multi-topic minutes summary system using word frequency and similarity analysis as an existing prior study.