• Journal of the Society of Disaster Information
• /
• v.13 no.2
• /
• pp.233-248
• /
• 2017

Uniform laws and regulations and reasonable design is necessary for the prevention of possible fire in super high-rise building. To this end, this study focused on super high-rise and massive building-related architectural review performance-based design (PBD) evaluation disaster impact assessment (DIA), and provided fire engineering measures for improving fire prevention on the basis of performance-based design by analyzing the buildings subject to these systems and problems in terms of contents. Above all, in the aspect of law and standard improvement, first, with regard to dual parts of two statutes though significant portion of them has the same contents in performance-based design (PBD) evaluation and disaster impact assessment (DIA), it is necessary to operate the systems after making them conform with each other and consolidating or abolishing them. Second, if it is impossible to consolidate or abolish performance-based design (PBD) evaluation and disaster impact assessment (DIA), the areas of contents of performance-based design (PBD) evaluation and disaster impact assessment (DIA) should be precisely classified and established. Next, engineering improvement measures against fire hazard in super high-rise building are as follows. First, it is necessary to revise the provisions of straight-run stairs in special escape stairs. And in case of installing a mechanical smoke exhaust system instead of smoke vent, sandwich pressurization used in the United Stated should be permitted. Second, with regard to smoke control system for special escape stairs, it was shown that there was necessity for revising the standards in order to enable air to be supplied according to section in case of fire, carrying out performance-based design, and the like from the early design stages to the completion stages. In the future, it is expected that an epoch-making contribution will be made to a decrease in casualties and property damage due to fire in case of super high-rise building where the results can be reflected after carrying out a study on maintenance and carrying out an additional study on other considerations of super high-rise building together with reflecting the improvement measures provided in the above-mentioned study.

• Journal of Environmental Impact Assessment
• /
• v.29 no.6
• /
• pp.414-429
• /
• 2020

For the management of rivers, the target water quality is set by establishing the total amount of water pollution and water environment basic plan. For Geumho river T-P has achieved the target water quality, but for BOD, COD, TOC the target water quality of the water environment basic plan has been exceed for the past five years. Therefore, the flow rate for satisfying the target water quality was simulated by analyzing the load, load density, and pollution contribution rate of the Geumho river using BOD, COD, TOC and by utilizing QUAL-MEV a one-dimensional water quality model. According to the analysis of the load, the BOD, COD and TOC all showed the highest levels at the Geumho C point at 9,832.2 kg/day 20,656.6 kg/day, and 15,545.1 kg/day. The load density was highest at 9.47 kg/day/㎢, 37.55 kg/day/㎢, 30.20 kg/day/㎢, and 17.19 kg/day/㎢, 39.14 kg/day/㎢ in Dalseocheon stream during the wet seasons and dry seasons. Pollution contribution rate was highest at about 25 percent for Palgeocheon stream during the wet season and about 50 percent for Dalseocheon stream during the dry season. In addition, the correlation analysis between organic materials showed in the main stream and tributaty of the Geumho river that COD-TOC was 0.8 or higherthan BOD-COD and BOD-TOC in both the wet seasons and dry seasons. And after surveying the total amount of water pollution and the target quality of the water environment basic plan at Geumho C, it was analyzed that an additional flow tate of 14 times and 22 times was needed as of April 2019 (3.46 ㎥/sec).

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.30 no.2B
• /
• pp.121-135
• /
• 2010

This study is to assess the effect of potential future climate change on the inflow of agricultural reservoir and its impact to downstream streamflow by reservoir operation for paddy irrigation water supply using the SLURP. Before the future analysis, the SLURP model was calibrated using the 6 years daily streamflow records (1998-200398 and validated using 3 years streamflow data (2004-200698 for a 366.5 $km^2$ watershed including two agricultural reservoirs (Geumgwang8 and Gosam98located in Anseongcheon watershed. The calibration and validation results showed that the model was able to simulate the daily streamflow well considering the reservoir operation for paddy irrigation and flood discharge, with a coefficient of determination and Nash-Sutcliffe efficiency ranging from s 7 to s 9 and 0.5 to s 8 respectively. Then, the future potential climate change impact was assessed using the future wthe fu data was downscaled by nge impFactor method throuih bias-correction, the future land uses wtre predicted by modified CA-Markov technique, and the future ve potentiacovfu information was predicted and considered by the linear regression bpowten mecthly NDVI from NOAA AVHRR ima ps and mecthly mean temperature. The future (2020s, 2050s and 2e 0s) reservoir inflow, the temporal changes of reservoir storaimpand its impact to downstream streamflow watershed wtre analyzed for the A2 and B2 climate change scenarios based on a base year (2005). At an annual temporal scale, the reservoir inflow and storaimpchange oue, anagricultural reservoir wtre projected to big decrease innautumnnunder all possiblmpcombinations of conditions. The future streamflow, soossmoosture and grounwater recharge decreased slightly, whtre as the evapotransporation was projected to increase largely for all possiblmpcombinations of the conditions. At last, this study was analysed contribution of weather, vegetation and land use change to assess which factor biggest impact on agricultural reservoir and stream watershed. As a result, weather change biggest impact on agricultural reservoir inflow, storage, streamflow, evapotranspiration, soil moisture and groundwater recharge.

• Journal of Wetlands Research
• /
• v.21 no.3
• /
• pp.191-198
• /
• 2019

High impervious surfaces increase the surface runoff during rainfall and reduces the underground infiltration thereby leading to water cycle distortion. The distortion of water cycle causes various urban environmental problems such as urban flooding, drought, water pollutant due to non-point pollution runoff, and water ecosystem damage. Climate change intensified seasonal biases in urban rainfall and affected urban microclimate, thereby increasing the intensity and frequency of urban floods and droughts. Low impact development(LID) technology has been applied to various purposes as a technique to reduce urban environmental problems caused by water by restoring the natural water cycle in the city. This study evaluated the contribution of hydrologic characteristics and water cycle recovery after LID application using long-term monitoring results of various LID technology applied in urban areas. Based on the results, the high retention and infiltration rate of the LID facility was found to contribute significantly to peak flow reduction and runoff delay during rainfall. The average runoff reduction effect was more than 60% at the LID facility. The surface area of the LID facility area ratio(SA/CA) was evaluated as an important factor affecting peak flow reduction and runoff delay effect.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.42 no.1
• /
• pp.50-63
• /
• 2014

Eco-tourism has been recognized as a form of sustainable development that simultaneously satisfies the need for environmental preservation and the activation of local economies. Although some research findings relating to its positive environmental and social effects have been published, there is still controversy regarding its pros and cons in terms of its actual economic benefits, and little research about how they can be increased. Thus, the following research analyzes how the tour activities, attitudes and satisfaction of 314 actual visitors was related with their consumption behaviors, by surveying tourists to Suncheon Bay, a highly popular destination with a large number of visitors. The results are as follows. First, if the tourists were involved in a link-up tour, had prior eco-tourism experience, or had researched information on SunCheon bay eco-tourism before their visit, these were all positively correlated with consumption behaviors, and increased the amount of money they spent. In particular, among tour spending activities, accommodation cost is shown to be highly correlated with tour activities. Second, Free Independent Tourist(FIT) tended to show more positive tour attitudes than package tourists, spending more on accommodation and experience programs. The visitors to SunCheon Bay showed strong environmental attitudes, followed by social and cultural attitudes, and economic attitudes, in that order, and tourists with positive attitudes had a high rate of participation in experience programs. In addition, program participants showed a willingness to donate, and high satisfaction. Therefore, the following thesis proposes that Free Independent Tourist(FIT) should be induced to increase their contribution to the local eco-tourism economy, and highlights the need to develop various experience programs, aggressive advertisements and educational activities.

• Journal of Korean Society of Environmental Engineers
• /
• v.33 no.1
• /
• pp.60-70
• /
• 2011

The sediment removal index derived from the chemical contaminants, $CI_{HC}$, is currently in use to identify and define the spatial extent of the contaminated sediments in the sea. In order to analyze the sensitivity of the ecological and human risk associated with contaminated sediment, we evaluated five hypothetical contaminated sediments, whose $CI_{HC}$ values are identical but consisted of different contaminant contents, using $TrophicTrace^{(R)}$ model dedicated to evaluate sediment risk, against the resident greenling (Hexagrammos otakii) and humans by calculating No-Observed-Adverse-Effect-Level based Toxicity Quotient (NOAEL TQ) and Lowest-Observed-Adverse-Effect-Level based Toxicity Quotient (LOAEL TQ), and cancer risks and hazard indices (HI), respectively, based on the site conceptual model and exposure assumptions of fish ingestion to human receptor populations. NOAEL and LOAEL TQ values varied as much as a factor of 2 among 5 hypothetical sediments. Chemical element specific contribution to the carcinogenic risk and HI varied also greatly in these sediments. The reason for this significant dissimilarity in ecological and human risk stems from the different risk of each contaminant to the resident fish and human receptor. When the conceptual food web model is constructed for the target biological species for a given site, the ecological and human risk analysis considering trophic transfer of contaminants will add a ecosystem based tool for the management of contaminated sediments.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.1
• /
• pp.1-9
• /
• 2022

The effect of sediments in a waste dumping area on marine organisms was evaluated using sediment toxicity tests with a benthic amphipod (Monocorophium acherusicum) and bioluminescent bacterium (Vibrio fischeri) in accordance with the Korean Standard Method for Marine Wastes (KSMMW). Nine sites in the East Sea-Byeong, East Sea-Jeong, and Yellow Sea-Byeong areas were sampled from 2016 to 2019. The test results showed that the relative average survival rate (benthic amphipods) and relative luminescence inhibition rate (luminescent bacteria) were below 30%, which were judged to be "non-toxic." However, in the t-test, a total of 12 benthic amphipod samples (6, 1, 1, and 4 in 2016, 2017, 2018, and 2019, respectively) were significantly different (p<0.05) from the control samples. To identify the source of toxicity on benthic amphipods, a simple linear regression analysis was performed between the levels of eight heavy metals (Cr, As, Ni, Cd, Cu, Pb, Zn, and Hg) in sediments and the relative average survival rate. The results indicated that Cr had the highest contribution to the toxicity of benthic amphipods (p = 0.000, R2 = 0.355). In addition, Cr was detected at the highest concentration at the DB-85 station and exceeded the Marine Environment Standards every year. Although the sediments were determined as "not toxic" according to the ecotoxicity criteria of the KSMMW, the results of the statistical significance tests and toxicity identification evaluation indicated that the toxic effect was not acceptable. Therefore, revising the criteria for determining the toxic effect by deriving a reference value through quantitative risk assessment using species sensitivity distribution curves is necessary in the future.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.47 no.4
• /
• pp.50-60
• /
• 2019

In the late 1980s, a financial crisis and Compulsory Competitive Tendering (CCT) in green space services brought with it a profound impact on the quality of parks in the UK. Such government projects, e.g. Urban Task Force (1999) and Public Parks Assessment (2001), aimed to raise the awareness of the severity of the declining standards of urban parks. Since the late 1990s, the UK governments (The New Labour (1997-2010) and The Conservative Government (2010-2019)), have often adopted community-led governance schemes to enhance the quality of parks and address problems derived from the financial crisis. Accordingly, community groups, notably 'Friends of', enlarged their involvement in the decision-making process of park management. However, there is little empirical evidence concerning the impact of community-led governance on park management, in particular, the effect on the users' perceptions of park use. This study explored the context of community-led park management to reclassify the level of build-up of governance underlined by 'A Ladder of Citizen Participation'. In addition, questionnaire surveys were conducted around two Sheffield district parks, which are located in deprived areas. As a result, community involvement in the status quo of UK urban park management has changed its form of governance based on the extent of involvement in the decision-making process. The forms of governance could be categorised in three levels: general, active, and predominant governance, where the extents of decision-making and sharing responsibility vary. The results obtained through the questionnaires show that one park (active governance), which has a stronger tendency of sharing responsibility to get involved in park management, had better contribution to park management and positive impacts on users' satisfaction than the other park (general governance). The findings highlight that stronger governance in partnerships with the non-public sectors can shed light on current and future park management through a shift in sharing responsibility for park management.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2009.06a
• /
• pp.187-187
• /
• 2009

Opening of fractures induced by shear dilation or normal deformation can be a significant source of fracture permeability change in fractured rock, which is important for the performance assessment of geological repositories for spent nuclear fuel. As the repository generates heat and later cools the fluid-carrying ability of the rocks becomes a dynamic variable during the lifespan of the repository. Heating causes expansion of the rock close to the repository and, at the same time, contraction close to the surface. During the cooling phase of the repository, the opposite takes place. Heating and cooling together with the, virgin stress can induce shear dilation of fractures and deformation zones and change the flow field around the repository. The objectives of this work are to examine the contribution of thermal stress to the shear slip of fracture in mid- and far-field around a KBS-3 type of repository and to investigate the effect of evolution of stress on the rock mass permeability. In the first part of this study, zones of fracture shear slip were examined by conducting a three-dimensional, thermo-mechanical analysis of a spent fuel repository model in the size of 2 km $\times$ 2 km $\times$ 800 m. Stress evolutions of importance for fracture shear slip are: (1) comparatively high horizontal compressive thermal stress at the repository level, (2) generation of vertical tensile thermal stress right above the repository, (3) horizontal tensile stress near the surface, which can induce tensile failure, and generation of shear stresses at the comers of the repository. In the second part of the study, fracture data from Forsmark, Sweden is used to establish fracture network models (DFN). Stress paths obtained from the thermo-mechanical analysis were used as boundary conditions in DFN-DEM (Discrete Element Method) analysis of six DFN models at the repository level. Increases of permeability up to a factor of four were observed during thermal loading history and shear dilation of fractures was not recovered after cooling of the repository. An understanding of the stress path and potential areas of slip induced shear dilation and related permeability changes during the lifetime of a repository for spent nuclear fuel is of utmost importance for analysing long-term safety. The result of this study will assist in identifying critical areas around a repository where fracture shear slip is likely to develop. The presentation also includes a brief introduction to the ongoing site investigation on two candidate sites for geological repository in Sweden.

• The Mathematical Education
• /
• v.51 no.3
• /
• pp.223-246
• /
• 2012

Korean Ministry of Education Science, and Technology(MEST) has recommended the introduction of mathematics textbooks based on storytelling to improve the teaching and learning of mathematics in school. As part of the mathematics textbooks based on storytelling development, this research has investigated school mathematics teachers' perspectives on mathematics textbooks based on storytelling in order to identify implications for the development and the implementation of it. For the purpose, we have developed survey questionnaire and administered it to 113 high school mathematics teachers. The survey asked the teachers to address their conception of mathematics textbooks based on storytelling, its contribution to school mathematics, challenges and obstacles for the implementation. The survey shows that the mathematics teachers' conception of mathematics textbooks based on storytelling was not clear or limited. Most of them replied that they received information about mathematics textbooks based on storytelling from the materials provided by workshop or materials of school district office. While the teachers heard about that school will implement mathematics textbooks based on storytelling, they rarely had idea of how to use them in class. In the survey, the teachers identified which type of storytelling is effective for which purpose of mathematics education. They also identified the positive effect and the difficulties in the implementation of mathematics textbooks based on storytelling. The mathematics teachers pointed out that textbook is not enough. They urged that the implementation of mathematics textbooks based on storytelling should be integrated into classroom teaching and assessment to make a significant change in the educational practice of mathematics in school. Thus, mathematics teachers need support to implement mathematics textbooks based on storytelling into their teaching practice. Teacher workshop and teacher manuals need to be developed to help teachers understand educational visions and values of mathematics textbooks based on storytelling. These results of the survey would form the worthwhile base information for the development and the implementation of mathematics textbooks based on storytelling.