• Journal of Korea Water Resources Association
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• v.52 no.12
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• pp.1011-1023
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• 2019

Rapid urbanization increases the risk of hydrologic disasters due to the increase of impervious areas in urban areas. Precipitation characteristics can be transformed due to the rise of global temperatures. Thus urban areas with the increased impervious areas are more exposed to hydrological disasters than ever before. Therefore, low impact development practices have been widely installed to rehabilitate the distorted hydrologic cycle in the urban area. This study used the Stormwater Management Model to analyze the water quantity and quality of the Mokgamcheon which had been severely urbanized, considering future climate scenarios presented by various general circulation models (GCMs). In addition the effectiveness of permeable pavement by 27 sub-watersheds was simulated in terms of water quantity and quality considering various GCMs and then the priorities of sub-watersheds were derived using an alternative valuation index which uses the pressure-state-response framework.

• Hwankyungkyoyuk
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• v.24 no.2
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• pp.112-130
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• 2011

The study is aimed to investigate the current status of ESD(Education for Sustainable Development) programs in private sector(businesses) carried out in Korea since UN DESD was launched in 2005, For this purpose we conducted a questionnaire survey and case studies on those companies who have supposedly pursued sustainability management Results of questionnaire surveys showed that those in charge of writing sustainability reports in companies had an extremely high understanding of SO, but were not well aware of ESD. These businesses started to pursue sustainable management due to global trends and decisions of CEOs, and most of them had divisions that took charge of or are responsible for sustainable management Sustainability issues that they mainly dealt with were corporate social responsibility, energy and climate change, but other issues were being covered, too. Internal stakeholders got involved in projects related to sustainability from the planning stage. Learning on sustainable management was primarily made through information delivery, and education programs were usually conducted for staff members and executives. Those who cooperated on their sustainable development projects were mostly local communities, universities, etc. They had few ESD programs that they directly developed and carried out, and few cases of ESD-related cooperation; and in those few cases, their partners were often elementary/middle/high schools and universities. Results of ESD case studies and questionnaire surveys showed that businesses dealt with various issues of sustainable development in addition to corporate social responsibility and diversified education programs were carried out inside these companies, Business themselves, therefore, need to be considered and researched in further detail as important targets of ESD as well as supporters or cooperation partners on ESD programme.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.162-177
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• 2020

Background: Ecologists have achieved much progress in the study of mechanisms that maintain species coexistence and diversity. In this paper, we reviewed a wide range of past research related to these topics, focusing on five theoretical bodies: (1) coexistence by niche differentiation, (2) coexistence without niche differentiation, (3) coexistence along environmental stress gradients, (4) coexistence under non-equilibrium versus equilibrium conditions, and (5) modern perspectives. Results: From the review, we identified that there are few models that can be generally and confidently applicable to different ecological systems. This problem arises mainly because most theories have not been substantiated by enough empirical research based on field data to test various coexistence hypotheses at different spatial scales. We also found that little is still known about the mechanisms of species coexistence under harsh environmental conditions. This is because most previous models treat disturbance as a key factor shaping community structure, but they do not explicitly deal with stressful systems with non-lethal conditions. We evaluated the mainstream ideas of niche differentiation and stochasticity for the coexistence of plant species across salt marsh creeks in southwestern Denmark. The results showed that diversity indices, such as Shannon-Wiener diversity, richness, and evenness, decreased with increasing surface elevation and increased with increasing niche overlap and niche breadth. The two niche parameters linearly decreased with increasing elevation. These findings imply a substantial influence of an equalizing mechanism that reduces differences in relative fitness among species in the highly stressful environments of the marsh. We propose that species evenness increases under very harsh conditions if the associated stress is not lethal. Finally, we present a conceptual model of patterns related to the level of environmental stress and niche characteristics along a microhabitat gradient (i.e., surface elevation). Conclusions: The ecology of stressful systems with non-lethal conditions will be increasingly important as ongoing global-scale climate change extends the period of chronic stresses that are not necessarily fatal to inhabiting plants. We recommend that more ecologists continue this line of research.

• Journal of Korean Neurosurgical Society
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• v.30 no.4
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• pp.486-492
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• 2001

Objective : Essential hyperhidrosis is a pathological condition of excessive sweating beyond that required to cool the body, though poorly understood, originating from a dysfunction of the sympathetic nervous system. Thoracoscopic sympathectomy is the most popular treatment for upper limb hyperhidrosis, because it is a safe, effective, minimally invasive, and time-saving method. However, the common complication is the compensatory hyperhidrosis in other areas of the body, notably on the back, chest, abdomen, and buttocks. Compensatory hyperhidrosis is severe enough for some people, especially those living in a warm climate or engaging in heavy physical activities, to regret ever having had operation. The pathophysiological mechanisms underlying compensatory hyperhidrosis are incompletely understood, even though it is thought to be a truly compensatory feature related to thermoregulation of the body. Materials and Methods : we studied the clinical features of total 233 patients who were diagnosed as essential hyperhidrosis and treated with thoracoscopic sympathectomy or sympathicotomy from March 1992 to July 2000. Results : The success rate of thoracoscopic sympathetic surgery(sympathectomy or sympathicotomy) was 98.7%. The global rate of compensatory hyperhidrosis was 77% ; 84% in group T2, 3 sympathectomy, 76% in group T2 sympathectomy, 43% in group T2, 3 sympathicotomy and 59% in group T2 sympathicotomy. The rate of embarrassing or disabling compensatory sweating was significantly higher in T2 sympathectomy and in T2, 3 sympathectomy than in T2 sympathicotomy and T2, 3 sympathicotomy with significancy in statistic analysis(p<0.01). The precipitating factors of compensatory hiperhidrosis, including heat(warm weather), anxiety, stress, and exertion were noted. The compensatory hyperhidrosis was the main cause of patient dissatisfaction after thoracoscopic sympathectomy. Conclusion : The degree of compensatory hyperhidrosis is closely related to the extent of thoracic sympathectomy.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.06a
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• pp.203-204
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• 2014

As the marine environment is becoming more important with growing demand for the marine transport due to the globalization, some advanced ports have made efforts to establish Green Port to protect the marine environment. The Korean ports as the world's fifth ranked country have also made efforts to establish Green Port but most efforts are focused on hardware aspects such as renewable energy generation, installation of AMP and fuel conversion of port facilities. The purpose of this study is to develop Eco-Ship assessment scheme for Green Port in a software aspect and present measures to improve global green-competitiveness of Korean ports through diversification of their efforts for Green Port.

• Atmosphere
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• v.25 no.2
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• pp.235-248
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• 2015

In this study, we analyzed the three dimensional variations (latitude, longitude, and height of Jet core) and wind speed of upper Jet stream in the East Asian region using recent 35 years (1979~2013) of four reanalysis data (NCEP-R2, MERRA, ERA-Interim. and JRA-55). Most of Jet core is located in $30.0{\sim}37.5^{\circ}N$ and $13.0{\sim}157.5^{\circ}E$ although there are slight differences among the four reanalysis data. The wind speed differences among reanalysis are about $3m\;s^{-1}$ regardless of seasons, the weakest in NCEP-R2 and the strongest in JRA-55. Although significance level is not high, most of reanalysis showed that the Jet core has a tendency of southward moving during spring and winter, but moving northward during summer and fall. This amplified seasonal variation of Jet core suggests that seasonal variations of weather/climate can be increased in the East Asian region. The longitude of Jet core has a tendency of systematically westward moving and decreasing of zonal variations regardless of averaging methods and reanalysis data. In general, the Jet core shows a tendency of moving south-west-ward and upward, getting intensified during spring and winter regardless of the reanalysis data. However, the Jet core shows a tendency of moving westward and downward, and getting weakened during summer. In fall, there were no distinctive trends not only in wind speed but also three dimensional locations compared to other seasons. Although the significance levels are not high and variation patterns are slightly different according to the reanalysis data, our findings are more or less different from the previous results. So, more works are needed to clarify the three dimensional variation patterns of Jet core over the East Asian region as a result of global warming.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.99-99
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• 2011

Fuel cell systems are a completely different form of electricity source that has been used so far and is an aggregation of multiple technologies with multidisciplinary features that can be operated safely only when gas and electrical safety are being considered. Since fuel cells generate through electrochemical reactions there are difficulties in ensuring electricity safety, power quality assessment, effective control and reliability standards for system faults using conventional inspection techniques and even though they are necessary as a primary means for reduction of CO2 owing to the Climate Convention, electrical safety assessment and measures are required for the prevention of faults in residential facilities. Although small-scaled distributed power supplies can be utilized as important means of peak control and energy management measures, research is required for observing the effects on the system and the development of inspection technology to ensure stable operation, and the electrical safety of residential fuel cell systems need to be assessed and the problems derived for establishing electrical safety standards. From the year 2002, Japan has established laws on technical safety standards and development and rules on the product specifications and standards for the industrialization of hydrogen fuel cells. Also, a lot of effort have been made for the commercialization of fuel cells by building one-stop certification services. Internationally, the IEC TC 105 has established international standards based on fuel cells. In order to protect the national interest, the country should be able to respond accordingly meet global standards. In fact, in Korea, to comply with the international trend, Korea Energy Management Corporation is establishing a certified agenda for fuel cells and Korean Agency for Technology and Standards is enacting technical standards for fuel cells. The current terms of fuel cells are that research has been focused more on the quality and performance of manufactured products rather than stable power operation and maintenance over time. In this paper, by considering the household fuel cell as a power device, the safety standards of the fuel cell system for a reliable operation with the existing power system is being proposed.

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.11a
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• pp.28-45
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• 2000

It was unusual crop weather for 1998 and 1999 compared with normal in Korea. The consecutive days of the optimum ripening period for rice plant that had daily mean temperature 21-23C for 40 days after heading, increased with long anomalies in 1998-99. The air temperature during ripening period was much higher than the optimum temperature and lower sunshine hour than normal in the local adaptability tests of newly developed rice lines during those years. In response of rice cultivation to warming and cloudy weather during crop season, the yield shall be decreased. Most scientists agree that the rate of heating is accelerating and temperature change could become increasingly disruptive. Weather patterns should also become more erratic. Agrometeorologists could be analyzed yearly variations of temperature, sunshine hour and rainfall pattern focused on transient agroclimate change for last a decade. Rice agronomists could be established taking advantage of real time agricultural meteorology information system for fertilization, irrigation, pest control and harvest. Also they could be analyzed the characteristics of flowering response of the recommended and newly bred rice cultivars for suitable cropping plan such as cultural patterns and sowing or transplanting date. Rice breeders should be deeply considered introducing the characteristics of basic vegetative type of flowering response like Tonsil rices as prospective rice cultivars corresponding to global warming because of the rices needed higher temperature at ripening stage than Japonica rices, photoperiod sensitive and thermo-sensitive ecotypes

• Environmental Engineering Research
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• v.16 no.3
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• pp.121-129
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• 2011

The completely mixed flow and plug flow (CAP) water quality model was developed for streams with discontinuous flows, a condition that often occurs in low base flow streams with in-stream hydraulic structures, especially during dry seasons. To consider the distinct physical properties of each reach effectively, the CAP model stream network can include both plug flow (PF) segments and completely mixed flow (CMF) segments. Many existing water quality models are capable of simulating various constituents and their interactions in surface water bodies. More complicated models do not necessarily produce more accurate results because of problems in data availability and uncertainties. Due to the complicated and even random nature of environmental forcing functions, it is not possible to construct an ideal model for every situation. Therefore, at present, many governmental level water quality standards and decisions are still based on lumped constituents, such as the carbonaceous biochemical oxygen demand (CBOD), the total nitrogen (TN) or the total phosphorus (TP). In these cases, a model dedicated to predicting the target concentration based on available data may provide as equally accurate results as a general purpose model. The CAP model assumes that its water quality constituents are independent of each other and thus can be applied for any constituent in waters that follow first order reaction kinetics. The CAP model was applied to the Geum River in Korea and tested for CBOD, TN, and TP concentrations. A trial and error method was used for parameter calibration using the field data. The results agreed well with QUAL2EU model predictions.

• Atmosphere
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• v.23 no.1
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• pp.63-71
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• 2013

KMA is operationally monitoring El Ni$\tilde{n}$o and La Ni$\tilde{n}$a events, which have tremendous impacts on global climate. Many scientific studies have used to define onset of El Ni$\tilde{n}$o and La Ni$\tilde{n}$a events based on the moving average and persistency of SST indices, and KMA has adopted such definition. Though the definition has been widely accepted, in the operational aspect there is a critical problem to use moving average and condition for the persistence. Because the future values for the SST indices cannot be used in the operational monitoring, the onset timing in El Ni$\tilde{n}$o and La Ni$\tilde{n}$a can be significantly delayed. We suggest here an appropriate definition of El Ni$\tilde{n}$o and La Ni$\tilde{n}$a events in the operational aspect. Instead of using the moving average and the condition for the persistence, the onset is defined based on NINO3.4 SST during last 3 months. In order to compare the new definition with the current KMA definition, we applied them to recent 60-years SST data. It is clear that the new definition can declare the onset timing of El Ni$\tilde{n}$o and La Ni$\tilde{n}$a several months earlier than that of the KMA definition. It suggest that the new definition is more appropriate to the operational monitoring on El Ni$\tilde{n}$o and La Ni$\tilde{n}$a.