• The Plant Pathology Journal
• /
• v.16 no.5
• /
• pp.257-263
• /
• 2000

Infection with rice blast fungus (Magnaporthe grisea) significantly reduced foliar net photosynthesis (A) of rice cultivars: Ilpoom, Hwasung, and Choochung in greenhouse experiments. By measuring the amount of diseased leaf area with a computer image analysis system, the relation between disease severity (DS) and net photosynthetic rate was curvilinearly correlated (r=0.679). Diseased leaves with 35% blast symptom can be predicted to have a 50% reduction of photosynthesis. The disease severity was linearly correlated (r=0.478) with total chlorophyll (chlorophyll a and chlorophyll b) per unit leaf area(TC). Light use efficiency was reduced by the fungal infection according to the light response curves. However, dark respiration (Rd) did not change after the fungal infection (p=0.526). Since the percent of reduction in photosynthesis greatly exceeded the percent of leaf area covered by blast lesions, loss of photosynthetic tissue on an area basis could not by itself account for the reduced photosynthesis. Quantitative photosynthetic reduction can be partially explained by decreasing TC, but cannot be explained by decreasing Rd. By photosynthesis (A)-internal CO$_2$ concentration (C$_i$ curve analysis, it was suggested that the fungal infection reduced ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activity, ribulose-1,5-bisphosphate (RuBP) regeneration, and inorganic phosphate regeneration. Thus, the reduction of photosynthesis by blast infection was associated with decreased TC and biochemical capacity, which comprises all carbon metabolism after CO$_2$ enters through the stomata.

• Journal of Korean Society of Water and Wastewater
• /
• v.28 no.1
• /
• pp.111-124
• /
• 2014

Decentralized water supply systems, treating the water in users'vicinity, cutting down the distribution system, utilizing the alternative water resources(rainwater harvesting, water reclamation and reuse and so on.) and saving energy and other resources, could be categorized into POU(Point-Of-Use), POE(Point-Of-Entry) and community small scale system. From the literature review, we could thought that decentralized water supply system and hybrid system(integrating centralized and decentralized water supply system within urban water management) might have strengthening comparative advantages to centralized system with respect to: (1) water security, (2) sustainability, (3) economical affordability. Even though it is difficult to derive and quantify direct benefit advantages from decentralized and hybrid system in comparison with centralized system, (1) operational cost reduction, (2) assurance for safe and stability water supply and (3) greenhouse gas reduction can be expected from successful establishment of the former.

• Journal of Auto-vehicle Safety Association
• /
• v.6 no.2
• /
• pp.72-77
• /
• 2014

In the ongoing debates over the need to identify new sources of energy and to reduce the emissions of greenhouse gases. Hydrogen has emerged as one of the most promising alternatives due to its emissions from the vehicle being virtually zero. The governments have identified the development of regulations and standards as one of the key requirements for commercialization of hydrogen-fueled vehicles. Regulations and standards will helpful in overcoming technological barriers to commercialization. Developments of a technique for safety assessment of Hydrogen Fuel Cell Vehicle(HFCV) includes four tasks, research for regulation system and policy, hydrogen safety, vehicle operation safety and protection against high-voltage. The objective is to establish a technique for safety assessment and amend safety standards for HFCV and consequently reflect research results to vehicle management policy. We devised safety standards and evaluation techniques with regard to high-pressure gas and high voltage of hydrogen fuel cell vehicle. Korean Motor Vehicle Safety Standards(KMVSS) for HFCV was amended to June 10, 2014. including the results of the safety assessment technology for high-voltage and hydrogen characteristics.

• Journal of Energy Engineering
• /
• v.27 no.1
• /
• pp.65-75
• /
• 2018

The emission of greenhouse gases mainly carbon dioxide and methane is the result of rapid industrialization to meet the demands of ever-growing population. This has resulted in an increase of global temperature which in turn is responsible for severe environmental, social, ecological and economic losses, commonly known as to as 'climate change'. This study attempts to highlight the impacts of climate change mainly focussing on water contamination, sanitation and open defecation in India. The requirement for the instantaneous employment of environment friendly technologies along with improved sanitary system has been discussed. Various other issues which are also linked to climate change that need further management like managing water resources, deterioration in human health, economic losses, modification and successful implementation of policies have been pointed out. Furthermore, stress has been made for the urgent adaptation and rethinking for making strategies along with the involvement of women in order to cop up challenges offered by climate change.

• Korean Journal of Organic Agriculture
• /
• v.20 no.2
• /
• pp.143-159
• /
• 2012

Agricultural income is calculated with producer price, output and management cost. This study compared organic farming with conventional one for agricultural income, producer price and output by items. And then it proposed the method of item selection and crop system from a diversification point of view. The coefficient of variation to producer prices in organic farming was 4.7%, and conventional one was 30.3% because organic products have been produced in a system of contract farming with consumers' cooperative. This result means the price of organic products is stabler than that of conventional price. And agricultural income of organic farming has been generally known more than that of conventional one. However, agricultural gross income of conventional farming was more than that of organic one by 20.3% in 2010. It was caused by output reduction of a few items(fer example; onion, large green onion, potato and young pumpkin) due to freak weather conditions and constant producer price for several years in organic farming. In order to increase agricultural income, appropriate crop selection and system should be introduced to organic farming. A principal crop is the rice plant and 2 subordinate crops are dry crops at bare field and greenhouse respectively. Thus 5 crop systems that agricultural gross income are relatively increased larger among 15 crop systems estimated are rice+ginger+cucumber, rice+ginger+tomato, rice+large green onion+cucumber, rice+sweet potato+cucumber and rice+onion+ cucumber.

• The Plant Pathology Journal
• /
• v.20 no.2
• /
• pp.92-96
• /
• 2004

Environmental factors such as soil moisture, land management, and weather conditions affecting Fusarium wilt of sweet potato were investigated in major sweet potato cultivation regions in Korea. Fusarium wilt occurred mainly in reclaimed terracing lands, which are flattened and located in hilly to mountainous areas at the base of the mountain, in early seasonal cultivation regions. Disease severity was lower in reclaimed fields with natural slope. The development of Fusarium wilt in the fields was highly correlated with precipitation during planting period (r=-0.96**). Fusarium wilt was more severe in fields with less than 20 cm of available soil depth than in fields with over 20 cm of available soil depth. Greenhouse studies were consistent with field studies that less soil moisture content caused severe Fusarium wilt of sweet potato. These results indicate that low rainfall and moisture of soil with low effective soil depth during planting period are important environmental factors influencing the development of Fusarium wilt.

• Journal of Environmental Impact Assessment
• /
• v.21 no.2
• /
• pp.265-277
• /
• 2012

This paper is primarily intended to present quantitative evidences for land surface albedo difference among seven metropolitan cites in South Korea. An empirical study for experimental sites was conducted to confirm how a standard MODerate Resolution Imaging Spectroradiometer (MODIS) instrument offers the viable method of measuring and comparing the regional heterogeneity of albedo among administrative districts. The metropolitan cities like Seoul located in dense building environment do result in much lower albedo than those exposed in much more sub-urban surface (e.g KwangJoo). These experimental results indicate that an urban surface such as building and road is a crucial explanatory variable for lower albedo. It is confirmed that the urban surface such as building and road could be employed as a proxy of the lower albedo burden in the metropolitan area. It is anticipated that this research output could be used as a valuable reference to confirm the potential of introducing the new concept of "administrative districts specific albedo management" to support more scientific and objective decision-making in the process of GHG (Greenhouse Gas) reduction project.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.13 no.2
• /
• pp.52-62
• /
• 2010

This study was carried out in the Tropical Plant Resources Research Center of Korea National Arboretum to determine the optimum edaphic environment for the growth of tropical and subtropical plants. The physicochemical properties of artificial substrates and the growth characteristics of tropical and subtropical plants were investigated. Subtropical plants exhibited a high growth rate when cultivated in a substrate of Dry Zone that had physical properties similar to those of arid native soil. Mediterranean plants showed a low growth rate when grown in a substrate of Subtropical Zone that required changes in acidity. The substrate of Tropical Zone had high organic matter and mineral contents and therefore had good physical properties:this substrate has a good environment for the stimulation of the growth of tropical plants. Our results indicate that the chemical properties such as pH and mineral contents of most artificial substrates need to be more urgently improved than their physical properties in order to ensure better growth of tropical and subtropical plants. Initial management strategies for the construction of new tropical greenhouses were formulated, and data from monitoring studies will be continuously gathered and incorporated in the manual to keep it updated.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.27 no.5
• /
• pp.38-47
• /
• 2000

Carbon dioxide is a major greenhouse gas causing climate change. This study quantified annual direct and indirect uptake of carbon by urban greenspace, and annual carbon release from vegetation maintenance and fossil fuel consumption. The study area was whole Chuncheon and Kangleung, and also two districts of Kangnam and Junglang in Seoul, cities located in middle Korea. Carbon uptake by urban greenspace played an important role through offsetting carbon release by 6-7% annually in Chuncheon and Kangleung. For Kangnam and Junglang, where the population density was relatively higher, urban greenspace annually offset carbon release by 1-2%. Future possible tree plantings could double annual carbon uptake by existing trees in urban lands (except natural and agricultural lands) of a study city. Based on study results, planning and management guidelines for urban greenspace were suggested to save energy and to reduce atmospheric $CO_2$ concentrations. They included selection of optimum tree species, proper planting location from buildings, design of multilayered planting, amendment of existing regulations for greenspace enlargement, avoidance f intensive vegetation maintenance, and conservation of natural vegetation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.10a
• /
• pp.147-148
• /
• 2015

To achieve high-yield, high-quality and safely sustainable development of agricultural and establish the standardization of agricultural production, processing, circulation management system, scientific methods must be used. But in plastic greenhouse, the traditional manual measurement way is still used in cultivation and measurement of relative humidity. In order to improve the efficiency of farm work, to make agricultural production more modernization, this paper combining with the sensor and display device to build a environment which can automatically adjust the humidity.