• Resources Recycling
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• v.27 no.1
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• pp.64-73
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• 2018

This study aims to analysis the environmental impact on waste catalyst recycling technology using entire life cycle assessment. Environmental impacts consist of the five categories of impacts: global warming, resource depletion, acidification, eutrophication, and photochemical oxide production. The waste catalyst recycling presently have a GWP 3.53 ton $CO_2$ equivalent/ton, a ADP 0.017 ton Sb equivalent/ton, a AP 0.051 $SO_2$ equivalent/ton, a EP 0.0092 $PO{_4}^{3-}$ equivalent/ton, a 0.0019 ton $C_2H_4$ equivalent/ton. The smelting reduction process is the greatest contributor to all categories of environmental impacts in waste catalyst recycling. Electricity used in the smelting reduction process is the major contributor of all impact categories.

• Journal of Korean Academy of Nursing
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• v.49 no.6
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• pp.701-712
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• 2019

Purpose: Despite the high drinking rates and the complexity of drinking behaviors in adolescents, insufficient attention has been paid to their drinking patterns. Therefore, we aimed to identify patterns of adolescent drinking behaviors and factors predicting the distinct subgroups of adolescent drinking behaviors. Methods: We analyzed nationally representative secondary data obtained in 2017. Our final sample included 24,417 Korean adolescents who had consumed at least one glass of alcohol in their lifetime. To investigate patterns of drinking behaviors, we conducted a latent class analysis using nine alcohol-related characteristics, including alcohol consumption levels, solitary drinking, timing of drinking initiation, and negative consequences of drinking. Furthermore, we investigated differences in demographics, mental health status, and characteristics of substance use across the latent classes identified in our study. To do so, we used the PROC LCA with COVARIATES statement in the SAS software. Results: We identified three latent classes of drinking behaviors: current non-drinkers (CND), binge drinkers (BD), and problem drinkers (PD). Compared to the CND class, both BD and PD classes were strongly associated with higher academic year, lower academic performance, higher levels of stress, suicidal ideation, lifetime conventional or electronic cigarette use, and lifetime use of other drugs. Conclusion: Health professionals should develop and implement intervention strategies targeting individual subgroups of drinking behaviors to obtain better outcomes. In particular, health professionals should consider different characteristics across subgroups of adolescent drinking behaviors when developing the interventions, such as poor mental health status and other substance use among binge and problem drinkers.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.2
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• pp.307-315
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• 2016

Many countries are trying to reduce a greenhouse gas to step up their fight against climate change. There are many studies related to building only for reducing a greenhouse gas in construction area but studies related to reducing a comprehensive environmental load including various pollutants that affects the global environment are lacking. This study aims to analyse the characteristics of environmental load by work type for tunnel projects. Analysis showed that seven work types, including lining concrete, shotcrete, tunnel portal and open-cut tunnel work, etc., are representative works generated environmental load. These seven works represent 89.22 percent of total environmental load. In addition, comparison results of environmental load per tunnel's length by work type showed that a major factor of environmental load is caused by a tunnel portal and open-cut tunnel work with relatively short length (excavation length). And lining concrete and shotcrete work are larger than any other environmental load with tunnel's total length. It is expected that the result of this study will be used to make a estimation model for environmental load using approximate quantity survey of representative work types in the early stage of tunnel design. And it will be play a considerable role in establishing of environment management plan for sustainable infrastructure construction.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.6
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• pp.405-412
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• 2011

Environmental impact by proposed pump and treatment remediation of groundwater contaminated with TCE over 0.6 mg/L down to 0.005 mg/L was assessed for 30 years operation in an industrial park. Total amount of groundwater treated was $2.96{\times}10^7m^3$ and the amount of TCE removed was 17.6 kg at most. The life cycle assessment was used to estimate the environmental cost and environmental benefit and their effects on the environment could be analyzed. Most of the environmental cost was accrued from electricity generation for 30 years pump operation, which includes energy consumption, resources consumption such as coal, crude oil, emission of global warming gas and acid gas into air, waste water production, and waste generation. Environmental impact could be quantified with a Life Cycle Assessment (LCA) model for soil and groundwater remediation and normalized based upon consumption and emission quantities per capita in the world. Among the normalized values, acidification material release was the most significant.

• Journal of Korean Society on Water Environment
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• v.29 no.2
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• pp.239-246
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• 2013

The foot and mouth disease and AI were highly contagious. The virus can be transmitted in a number of ways, including close-contact animal to animal spread, long-distance aerosol spread and fomites, or inanimate objects, typically fodder and motor vehicles. A lot of burial sites were constructed in a short time for preventing the rapid spread of the virus. The carcass burial sites have a risk potential because the sites were constructed without any appropriate and systematic management. It resulted from lacking of time, equipments and man power. The carcass burial sites more than 4,700 constructed in 2011. Approximately 7 million poultry and 3.5 million livestock including head of cattle and swine were buried in farm land. It is time to be concerned if the secondary pollutions occur from the burial sites. The environmental impacts should be analyzed for managing the burial sites effectively and minimizing damages and risks to the environment and human health. This study was to analyze environmental impacts of the process of carcass burial construction using a life cycle assessment methodology. All input data of raw materials and energy usage were collected and the inventory was constructed. The results showed that 1 ton of carcass burial of the environmental impacts were $0.51yr^{-1}$ for ADP, 0.09 kg of 1,4DCB-eq for FAETP, 31.17 kg of $CO_2-eq$ for GWP, 0.04 kg of $C_2H_4-eq$ for POCP, 0.06 kg of $SO_2-eq$ for AP.

• Korean Journal of Construction Engineering and Management
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• v.19 no.6
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• pp.86-93
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• 2018

Infrastructure which mandatory in human life causes large environmental loads when they are being installed and maintained. Especially, maintenance is performed over a long period of time. Also, there is a limit to suggest a reliable estimated value because environmental loads are changed according to methods of maintenance and periods. In this study, we developed a Environmental Load Estimating Model to evaluate value and plan as soon as possible in the Early Design Phases while maintaining a tunnel. To estimate environmental loads by using brief design information, we analyze a calculation methodology of environmental loads in maintenance phases. Furthermore, we apply periods of maintenance work and maintenance factors considered a characteristic of long-term maintenance. Finally, a main purpose is that this program makes all users estimate environmental loads in maintenance phases easily and quickly. Accordingly, it is considered that the Environmental Load Estimating Model offer assistance to eco-friendly maintenance of the road and tunnel construction.

• Korean Journal of Child Studies
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• v.38 no.2
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• pp.165-176
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• 2017

Objective: Delinquent peers are important predictors of adolescent delinquent behavior. Few studies have classified individuals into groups based on patterns of delinquent behavior among youth and their peers. This study identified latent groups based on adolescent-peer delinquency and examined psychosocial characteristics of each latent group. Methods: First, the study employed latent class analysis based on a nationally representative data of South Korean middle school students (N = 2,277). Both adolescent and peer delinquent behaviors comprised 13 items in the questionnaire that was self-reported by adolescents. Second, the study used multivariate regression models to analyze psychosocial symptoms of latent groups and conducted Wald tests to compare differences among latent groups. Results: Patterns of adolescent-peer delinquency were classified into six latent groups. "Mutual total delinquent group (1.2%)" showed high rates in most delinquent experiences. "Mutual status delinquent group (5.7%)" mainly experienced status delinquency, "Mutual violence delinquent group (5.3%)" showed high rates of violent delinquency. "Peer-only total high delinquent group (3.8%)" reported friends to have engaged in all types of delinquency and "Peer-only total medium delinquent group (11.8%)" reported peer involvement in multiple status and few violent delinquency. Finally, "low risk group (72.2%)" reported low rates of delinquency for themselves and their friends. Regression analysis showed that every "mutual" delinquent group presented significantly worse psychosocial problems than the "low risk group." Conclusion: Using person centered latent class analysis, this study classified six latent classes while considering both delinquent agents and various types of delinquency and investigated specific groups with greater risk of psychosocial problems.

• KIEAE Journal
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• v.14 no.1
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• pp.101-111
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• 2014

The Product Carbon Footprint Labeling has been run for more than four years by the Ministry of Environment and there are number of products labeled by KEITI(Korea Environmental Industry & Technology Institute), as for declaring products with their carbon emission during life cycle stages. There are several categories for certifying products by the characteristics of usage. Building products which are applied to a building as combined components or elements, are classified as production goods which means that the products are chosen by a business, not by a final consumer. In this paper, current status of PCF labeling has been reviewed focused on building products and the characteristics of carbon emission by a kind of product such as interior products, window products, structural products, system products and others. Until Dec. 2013, 82 products has been labeled and it covers about 53% among labeled product goods by the certification. Among the labeled building products, interior products are main products. From the results of comparison, variations of emission amounts by products have been found and the cause of variation could be explained by the purpose and material properties of products. However, the exact reason for variations cannot be acquired because of lack of information and the short operation period of the certification program. Further studies and more products are needed to be studied and analyzed focused on the emission characteristic by each product and to suggest reduction technologies for sustainable building products.

• Clean Technology
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• v.23 no.3
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• pp.256-269
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• 2017

In response to national and international regulations for resource circulation and to reduce greenhouse gas emissions, the automotive industry has tried to reuse scrap parts and defective products produced in the disposal or production stages as recycled resources. Attempts have been made to reach the target recycling rate by reducing the number of material types required for each part. Moreover, in order to achieve greenhouse gas reduction targets while maintaining the performance of existing products, lighter components are being developed. Existing products were 100% incinerated at the disposal stage, but the uni-materialized products were improved to be possible that it could be recycled 90% through scraps and the defective product in the pre-production and production stage. It also appears that the fuel efficiency improves through 56% lightweight compared to the existing product. In this paper, a preliminary assessment is conducted on the applicability of uni-materialized product development of car parts. The environmental impact values of existing products and developed prototypes are compared and analyzed through life cycle assessment.

• Journal of Korea Multimedia Society
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• v.9 no.10
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• pp.1322-1331
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• 2006

Concurrency control is one of the important factors to maintain consistent conditions of a game because most participants of the game should be shared information to play the game through a distributed network system. replay delay times should establish in every event and the received event should be saved and performed simultaneously for Concurrency Control. However, it is not easy to practice the event with same speed in environment having various moving speed. Therefore, expansion have to be provided. In other words, one of the most important factors of a game's efficiency is the process of bandwidth and delay. the process of concurrency control method based on scalable prediction for Multi-platform games would minimize the loss rate of a event and then would improve the interaction capacity of a game. It also might get reliability between clients. This paper analyzes some problems in terms of a layout of a game that integrates a cable and a wireless system. In addition, this paper provides methods to expand bandwidth and delay that might be an obstacle of a On-line game and to ensure reliability between a server and a client.