• Journal of Korean Society on Water Environment
• /
• v.25 no.3
• /
• pp.386-393
• /
• 2009

This study was carried out to assess water quality and to introduce the management measures for water quality improvement with the collected data from 87 agricultural reservoirs in Han river watershed. According to the water quality criteria (WQC) for lake based on the COD, TP, TN and chl.a concentration, 18, 16, 4 and 19 of 87 reservoirs exceed class IV, respectively. Based on the trophic state index (TSI) with chl.a concentration, 51 of selected reservoirs appeared to be eutrophic. Phosphorus was limiting nutrient on algal growth in 58 reservoirs. TP, chl.a and COD concentration in 23 of 49 agricultural reservoirs with chl.a concentration ${\geq}25{\mu}g/L$ and eutrophic exceed class IV by WQC. Also, the mean depth in 21 of 23 reservoirs was below 5m. Our results suggest that advanced wastewater treatment and crop land control in watershed of reservoirs with TP concentration ${\geq}0.1mg/L$ would be a effective tool to improve water quality. Dredging would to be effective measure in reservoirs with mean depth < 5 m and relatively old age. In reservoirs with chl.a concentration ${\geq}50{\mu}g/L$, application of technique such dissolved air flotation (DAF) and P inactivation be effective to improve water quality by removing particulate matters in water column. The management measure to control inflow such as sedimentation basin, Pre-dam and diversion would to be application in reservoirs with shallow depth, while large watershed and surface area.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.5
• /
• pp.677-684
• /
• 2022

This study is a basic study to evaluate the ecological environment of Changwon City. The study site was 6 ecotourism districts in Changwon-si, and the ecotourism index was evaluated through direct visits and interviews with the person in charge through preliminary research and various literature data from June to July 2021. There are six ecotourism indicators: climate crisis, air quality improvement, water conservation, natural coexistence, citizen participation, and tourism resource management. When looking at the scores for the six ecotourism areas in Changwon, it received the highest score in the areas of natural coexistence and air quality improvement. However, the ecoregion received the lowest score in the water resource conservation category, indicating that the water resource conservation as a whole was weak. Next, tourism resource management, climate crisis, and citizen participation are at the same level in all regions. As a result of the evaluation through the low-carbon ecotourism index, the Changwon City low-carbon ecotourism certification system should first be operated as a measure to revitalize the ecotourism region. It is necessary to prepare a low-carbon ecotourism level for Changwon City. Second, it is very important to guide and promote ecotourism areas to revitalize ecotourism areas. Lastly, to operate a sustainable eco-environment area, it is necessary to operate using local governance above all else.

• Korean Journal of Remote Sensing
• /
• v.38 no.4
• /
• pp.387-394
• /
• 2022

Coastal upwelling is a significantly imperative process for understanding the interactions between physical and ecological processes and has been investigated incessantly. In this study, we explored the upwelling index, specifically upwelling age (UA). UA enabled us to observe the initiating, sustaining, and decaying upwelling processes. Although the sensitivity of many other geophysical parameters to estimate UA has been investigated, the wind direction has not been evaluated. Thus, we assessed the appropriate wind direction for the UA and obtained efficient upwelling signals from the four coastal stations. Furthermore, we applied the UA and compared it with the satellite sea level anomaly, sea surface temperature, and chlorophyll-a changes to validate how UA depicts their spatial extents. Thus, UA can predict the timing of coastal upwelling events using predicted geophysical parameters.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.41 no.3
• /
• pp.247-255
• /
• 2021

Individual passenger transfer information is not included in Seoul metropolitan subway Automatic Fare Collection (AFC) data. Currently, basic data such as travel time and distance are allocated based on the TagIn terminal ID data records of AFC data. As such, knowledge of the actual path taken by passengers is constrained by the fact that transfers are not applied, resulting in overestimation of the transport index. This research proposes a method by which a transit path that connects the TagIn and TagOut terminal IDs in AFC data is determined and applied to the transit index. The method embodies the concept that a passenger's line of travel also accounts for transfers, and can be applied to the transit index. The path selection model for the passenger calculates the line of transit based on travel time minimization, with in-vehicle time, transfer walking time, and vehicle intervals all incorporated into the travel time. Since the proposed method can take into account estimated passenger movement trajectories, transport-related data of each subway organization included in the trajectories can be accurately explained. The research results in a calculation of 1.47 times the values recorded, and this can be evaluated directly in its ability to better represent the transportation policy index.

• International Journal of Computer Science & Network Security
• /
• v.22 no.7
• /
• pp.21-28
• /
• 2022

The increase in the number of large cities and the size of their population sharpens attention to the new role of cities as entities to ensure a high-quality, safe and modern life of citizens, which has become significantly more active in recent years. The rapid spread of smart cities in the modern world has actualized the issue of analyzing their success and assessing the role of various factors in this. Every success of a smart city is always the result of a unique combination of the most modern technologies, environmental and social initiatives, skillful and consistent management, as well as available human potential. The purpose of the article is to analyze the success factors of smart cities based on the generalization of the results of the most famous ratings. In order to identify the impact of various factors, primarily intellectual, on the success and leadership positions of smart cities, the following ratings were consistently analyzed: Smart City Index (SCI), City in Motion Index (CIMI), Global Power City Index (GPCI), Global Cities Index (GCI), Global Cities Outlook (GCO). They have a different list of indicators and main pillars (dimensions), but all ratings take into account aspects such as: governance, ICT, mobility, functionality, human capital, etc. The highest correlation coefficient, that is, the strongest linear relationship of the CIMI index was found with such factors as: Human capital, Economy, Governance and Technologies. Summarizing the results of the TOP 20 smart cities according to different ratings allowed us to confirm that the list of leaders is very similar in all ratings. Among those cities that are in the TOP-20 in all five indexes are: London, Sydney and Singapore. There are four indices: New York, Paris, Tokyo, Copenhagen, Berlin, Amsterdam, Melbourne. Achieving leadership positions in smart city rankings is always the result of a combination and synergy of certain factors, and first of all, it is the quality of human capital. The intensity and success of the use of information and communication technologies in locality management processes, city planning and improvement of the city's living conditions depend on it.

• Journal of Korea Water Resources Association
• /
• v.34 no.3
• /
• pp.231-240
• /
• 2001

The problem of the flocculation basin was induced by installing the pilot plant using tracer test at Yang-Duck water treatment plant in Pohang cite. The flocculation basin model downscaled as 1/20 was made of acryl and evaluated hydraulically by transforming the section of the effluent in the flocculation basin. The optimum section of the effluent was suggested and applied to the plant. The efficiency of the flocculation basin according to improvement was evaluated by the particle counter which can count the number of particles each size fraction. The results of this study are as follows : First, it was desirable to make the retention time as short as possible because the flow and the index value were similar regardless of the retention time. Second, after the modification in Yang-Duck water treatment plant, the problem of destruction of floe was improved and the plant was operated satisfactorily. The hydraulic experiment with tracer test can be applied to the performance evaluation as well as improvement of facility in unit process of existing water treatment plant. Additionally, it can be used to find a design factor in the new water treatment plant.

• Korean Journal of Construction Engineering and Management
• /
• v.21 no.2
• /
• pp.47-58
• /
• 2020

The ICEC (Index of Construction Engineer's Competency) quantifies the competence of construction engineers using such parameters as experience, education, and qualifications and assigns four technical grades (expert, advanced, intermediate, and beginners) to construction engineers according to their scores for the efficient management and loading of technical personnel. However, as of 2020, the seventh year since its implementation, ICEC has shown many problems in its application, unlike its intended purpose. So institutional supplementation is required to provide improvement measures that can cope with the changing labor market environment and complement the current ICEC. Therefore, this study examined the current status of the career management system after the introduction of the ICEC, suggested a career index proportional to the competence of construction engineers from the beginner to the expert level, and developed an effective capability evaluation model I²CEC. The improved model presented in this study provides a means to comprehensively judge the performance, experience, and the professional work abilities of construction management engineers. Furthermore, the results of this study are expected to contribute to the development of efficient manpower and career management systems for enhancing the competitiveness of the domestic construction industry.

• Journal of Environmental Science International
• /
• v.17 no.10
• /
• pp.1093-1109
• /
• 2008

This paper aims to provide a fundamental basis for the improvement and verification of existing wind chill temperature index through the observation of skin temperature change of human body with air temperature and wind speed. For this, we control air temperature $5^{\circ}C$ interval from $0^{\circ}C$ to $-20^{\circ}C$ and classify wind speed by 0, 2, 6 and 8 m $s^{-1}$ respectively. The results are as follows; At each combination of air temperature and wind speed, the reduction rate of the mean skin temperature are different. When our body is exposed to the atmosphere, the mean skin temperature decreases at an exponential rate. The duration of the steady state is more than one hour, while it decreases with strong wind speed. Among 4 sites on a face, the skin temperature of forehead is the highest, followed by one of chin, left cheek, right cheek in orders. Especially, since the skin temperature of right cheek is the lowest, we think that it is suitable to use the data set of the right cheek skin temperature for the development of a Korea wind chill temperature index as a worst case.

• Journal of Environmental Science International
• /
• v.22 no.3
• /
• pp.269-279
• /
• 2013

In this paper, an environmental assessment was carried out on the whole process of industrial business activities to establish a basic plan for climate change mitigation and energy independency. The whole process was divided into each discharge process in terms of water, air, solid waste, green house gases and refractory organic compounds. The flowcharts and basic unit of process were analysed for three years (2008-2010), being utilized as basic information for the life cycle assessment. It was found that the unit loading for the whole process significantly depends on changes in the operation rate change and highly concentrated wastewater inflow. About 35% of solid waste production was reduced by improving the incineration method with co-combustion in coal boiler, generating about 57% of electricity used for the whole process, and consequently reducing the energy costs. As the eco-efficiency index was found to be more than 1, compared to the previous years, it can be said that improvement in general has taken place.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2004.05b
• /
• pp.516-520
• /
• 2004

Stream Naturalness means the index of natural state in stream's ecosystem. The evaluation of stream naturalness can evaluate relatively the effect of environmental damages by human and to show how significantly current stream has been apart from its natural state. And it could be show what is the meaning of importance in stream's ecosystem by such distinctions and it Is done by showing the need how a large scale of action for restoration to be restored to natural state of stream system. In this study, a set of index for Stream Naturalness evaluation is proposed, which is referred to and modified problems with domestic and foreign study cases. This methodology is supposed to show well the characteristics of stream in Korea. A case study of Hong-Chun River shows how this methodology is applied to the Stream Naturalness evaluation. For improving the function of river which are water use and flood control and for preserving the function of inhabitation, the proposed methodology is expected to be used a index of direction for a environmental project related stream improvement by evaluation of ecologically sound function in streams.