• Title/Summary/Keyword: LCA method

Search Result 143, Processing Time 0.027 seconds

Latent causal inference using the propensity score from latent class regression model (잠재범주회귀모형의 성향점수를 이용한 잠재변수의 원인적 영향력 추론 연구)

  • Lee, Misol;Chung, Hwan
    • The Korean Journal of Applied Statistics
    • /
    • v.30 no.5
    • /
    • pp.615-632
    • /
    • 2017
  • Unlike randomized trial, statistical strategies for inferring the unbiased causal relationship are required in the observational studies. The matching with the propensity score is one of the most popular methods to control the confounders in order to evaluate the effect of the treatment on the outcome variable. Recently, new methods for the causal inference in latent class analysis (LCA) have been proposed to estimate the average causal effect (ACE) of the treatment on the latent discrete variable. They have focused on the application study for the real dataset to estimate the ACE in LCA. In practice, however, the true values of the ACE are not known, and it is difficult to evaluate the performance of the estimated the ACE. In this study, we propose a method to generate a synthetic data using the propensity score in the framework of LCA, where treatment and outcome variables are latent. We then propose a new method for estimating the ACE in LCA and evaluate its performance via simulation studies. Furthermore we present an empirical analysis based on data form the 'National Longitudinal Study of Adolescents Health,' where puberty as a latent treatment and substance use as a latent outcome variable.

The Economic Efficiency Assessment of Infrastructure considering Environmental Cost - A Case Study of Emergency Spillway for Korean Multipurpose Dam - (환경비용을 고려한 공공시설물의 환경경제성 평가 -국내 다목적댐 비상여수로 시설 사례연구 -)

  • Kwun, Suk-Hyun;Kim, Sang-Bum
    • Korean Journal of Construction Engineering and Management
    • /
    • v.8 no.3
    • /
    • pp.168-176
    • /
    • 2007
  • This study aims to provide useful information when making a decision for the environmental and economic efficiency assessment of infrastructure, based on Life Cycle Assessment(LCA). It estimates environmental cost on environmental pollutants that are possible to happen by locations and by types of emergency spillway for korean multipurpose dam, which is selected as a study case. For this purpose, this study examines the theories of LCA and Contingent Valuation Method(CVM) and suggests an analysis model of environmental cost. To apply the suggested analysis model of environmental cost for infrastructure to the case study of emergency spillway at the multipurpose dam, this study calculates environmental load on environmental pollutants that generate during life cycle, converts it to a cost to predict environmental cost, evaluates environmental economy of emergency spillway by the estimated result, and draws the optimum alternative that is environmental-friendly and economic.

An Analysis of Potential Environmental Impact Reduction for Combined Sewer Overflow Project using a LCA Methodology (LCA 기법을 활용한 합류식 하수도 월류수 사업의 잠재적 환경영향 저감효과 분석)

  • Jo, Hyun-Jung;Song, Jang-Hwan;Hwang, Yong-Woo;Park, Ji-Hyoung
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.25 no.6
    • /
    • pp.885-892
    • /
    • 2011
  • In this study, LCA(Life Cycle Assessment) on 'Saemangum CSO Project' was carried out to evaluate environmental impact which occurred during the construction and operation periods and the potential environmental impact reduction was analyzed by comparing production and reduction level of pollution loads. LCA was conducted out according to the procedure of ISO14040 which suggested Goal and Scope Definition, Life Cycle Inventory Analysis, Life Cycle Impact Assessment and Interpretation. In the Goal and Scope Definition, the functional unit was 1 m3 of CSO, the system boundary was construction and operation phases, and the operation period was 20 years. For the data collection and inventory analysis, input energies and materials from civil, architecture, mechanical and electric fields are collected from design sheet but the landscape architecture field is excepted. LCIA(Life Cycle Impact Assessment) was performed following the procedure of Eco-Labelling Type III under 6 categories which were resource depletion, eutrophication, global warming, ozone-layer destruction, and photochemical oxide formation. In the result of LCA, 83.4% of environmental impact occurred in the construction phase and 16.6% in the operation phase. Especially 78% of environmental impact occurred in civil works. The Global warming category showed the highest contribution level in the environmental impact categories. For the analysis on potential environmental impact reduction, the reduction and increased of environmental impact which occurred on construction and operation phases were compared. In the case of considering only the operation phase, the result of the comparison showed that 78% of environmental impact is reduced. On the other hand, when considering both the construction and operation phases, 50% of environmental impact is increase. Therefore, this study showed that eco-friendly material and construction method should be used for reduction of environmental impact during life cycle, and it is strongly necessary to develop technology and skills to reduce environmental impact such as renewable energies.

A Method of River Environmental Impact Assessment using LCA (LCA를 적용한 하천환경영향평가 방법)

  • Kim, Sung-Joon;Jin, Ming-Ji;Jeon, Yong-Tae;Shin, Seon-Mi;Choe, Yong-Seung;Won, Chan-Hee
    • Journal of Environmental Impact Assessment
    • /
    • v.21 no.1
    • /
    • pp.93-104
    • /
    • 2012
  • In this research LCA methodology was adapted and analyzed in quantifying estimation of estuarine environment. The analysed objects of estuarine environment were construction methods, facility, and input material into water, and estuarine ecosystem. In this research the function of LCA of estuarine environment was river with the view of controling water, utilizing water, and hydrophilic function. According to the result of research, environmental damage indicator of facility was decreased 346 Pt from 453 Pt at pre-maintenance to 107 pt at post-maintenance. Among raw and subsidiary materials, remicon, stone-netting bag, and pebbles were showing heavy environmental load in the order. Evironmental impact of input material into water system was analyzed from 1,827 Pt environmental load before construction to 1,080 Pt of post-maintenance, and damage indicator was improved at 747 Pt. Water quality was improved from 1,827 Pt (before construction) to 1,080 Pt(after construction), and ecosystem was improved after maintenance. Environmental indicator in ecosystem was analyzed 427 Pt(before construction) to 348 Pt(after construction), and damage indicator of Sumnjingang riverine system was improved as much as 79 Pt. In the conclusion, estuarine environmental monitoring through LCA in the area of facility, input material into water and ecosystem showed that close-to-nature stream was 1,172 Pt better than artificial stream in environmental aspects.

A quantitative analysis of GHG emissions from the Korean large scale purse seine fishery using LCA method (전과정 평가 방법에 의한 한국 대형선망의 온실가스 배출량 정량적 분석)

  • Lee, Jihoon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.49 no.3
    • /
    • pp.282-290
    • /
    • 2013
  • The global warming related to GHG (greenhouse gases) emissions from industries is a major issue globally. Furthermore, GHG emissions from the fishery industries also represent an important issue, as indicated by "The Code of Conduct for Responsible Fisheries" at the Cancun, Mexico, meeting in 1992 and by the Kyoto protocol in 2005. Korea pronounced itself to be a voluntary exclusion management country at the 16th IPCC at Cancun, Mexico, in 2010. However, few analyses of GHG emissions from Korean fisheries have been performed. Therefore, a quantitative analysis of GHG emissions from the major Korean fisheries is needed before guidelines for reducing GHG emissions from the fishing industry can be established. The aim of this study was to assess the present GHG emissions from the Korean Purse seine fishery using the LCA (life cycle assessment) method. The system boundary and allocation method were defined for the LCA analysis. The fuel consumption factor of the purse seine fishery was also calculated. The GHG emissions for the edible fish were evaluated by determining the weights of whole fish and gutted fish. Finally, the GHG emissions required to produce 1kg of whole fish and 1kg of edible fish were deduced. The results will help determine the GHG emissions from the fishery. They will also be helpful to stakeholders and the government in understanding the circumstances involved in GHG emissions from the fishing industry.

A Study on the Evaluation Method of Green Remodeling Considering LCA and LCC (LCA 및 LCC를 고려한 환경친화적 리모델링의 평가방법에 관한 연구)

  • Lee, Gwan-Ho;Kim, Nam-Gyu;Rhee, Eon-Ku
    • Journal of the Korean Solar Energy Society
    • /
    • v.23 no.1
    • /
    • pp.57-67
    • /
    • 2003
  • This study aims to presents Evaluation Method of Green Remodeling that analyze the value of environment through expense, using the method of life cycle cost and life cycle assessment simultaneously. The results of this study are summarized as follows. Evaluation Model developed in this study can convert economical value of environment into cost by integrating. In addition, the model can apply as a useful tool to estimation of economical design alternative as well as quantification of environmental loads and costs. Evaluation Model presented In this study observe energy consumption and the environmental load emission with qualification, it can forecast effect of environmental cost that cost estimation is expected to be added to energy cost rate by being possible. Synthetically, when Estimation Model and computer program that developed in this study is applies to the construction industry; reasonable management of environmental load is convenient at each step of Green Remodeling. In addition, at preliminary design phase, practical use may be possible by reasonable yardstick about various alternatives and improvement of design alternatives likewise by grasping environmental effect.

Evaluation Method of Green Construction Technologies Using Integrated LCC and LCA Analysis (LCC-LCA 통합 분석에 의한 친환경 건설기술 평가방법)

  • Kim, Yoon-Duk;Cha, Hee-Sung;Kim, Kyung-Ra;Shin, Dong-Woo
    • Korean Journal of Construction Engineering and Management
    • /
    • v.12 no.3
    • /
    • pp.91-100
    • /
    • 2011
  • Green technologies of buildings are spreading for saving resource and energy consumption during life cycle of buildings. However, selection of optimized the technologies for applying projects is needed a lot of time and costs. Therefore prioritization is necessary to apply the technologies for buildings. An evaluation of economic value for the technologies is significant for prioritization of the technologies, however, the current evaluation system of economic value for technologies is not reflected the accurate features of the technologies. Green technologies have the objectives for reducing the emission of CO2 and saving the cost during the whole lifecycle of buildings. Thus the evaluation of economic feasibility for green technologies is needed to include the economic value from improving the environment. This paper developed the economic evaluation method integrated with LCC and LCA to accurately analyze the economic value for green technologies. Moreover, this paper drew the priority of the technologies by conducting case studies with the integrated method and analyzing the results with AHP. The conclusion of case studies, Green technologies is worth more if to include the economic value from improving the environment. Then in analysis of priority, Green intelligent component technologies were rated the highest. The conclusion of the study is able to utilize the supporting tool for making decision to select the optimized technologies for the projects and precedence study for developing future research of prioritization for green technologies. The future study for improving the developed method will supplement the various evaluation factors and apply the detailed weight to analyze the priority of green technologies.

A quantitative analysis of greenhouse gases emissions from bottom pair trawl using a LCA method (전과정평가방법에 의한 쌍끌이 대형기선저인망의 온실가스 배출량 정량적 분석)

  • Yang, Yong-Su;Lee, Dong-Gil;Hwang, Bo-Kyu;Lee, Kyoung-Hoon;Lee, Jihoon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.51 no.1
    • /
    • pp.111-119
    • /
    • 2015
  • The negative factors of fishery in environmental aspect of view are Greenhouse gas emission problems by high usage of fossil fuel, destruction of underwater ecosystem by bottom trawls, reduction of resources by fishing and damage of ecosystem diversity. Especially, the Greenhouse gas emission from fisheries is an important issue due to Canc$\acute{u}$n meeting, Mexico in 1992 and Kyoto protocol in 2005. However, the investigation on the GHG emissions from Korean fisheries did not much carry out. Therefore, the quantitative analysis of GHG emissions from Korean fishery industry is needed as a first step to find a relevant way to reduce GHG emissions from fisheries. The purpose of this research is to investigate which degree of GHG emitted from fishery. Here, we calculated the GHG emission from Korean bottom pair trawl fishery using the LCA (Life Cycle Assessment) method. The system boundary and input parameters for each process level are defined for LCA analysis. The fuel use coefficient of the fishery is also calculated. The GHG emissions from the representative fishes caught by bottom pair trawl will be dealt with. Furthermore, the GHG emissions for the edible weight of fishes are calculated with consideration to the different consuming areas and slaughtering process also. The results will be helpful to understand the circumstances of GHG emissions from Korean fisheries.

A quantitative analysis of greenhouse gas emissions from the major coastal fisheries using the LCA method (전과정평가방법에 의한 주요 연안어업의 온실가스 배출량 정량적 분석)

  • KIM, Hyun-young;YANG, Yong-su;HWANG, Bo-kyu;LEE, Jihoon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.53 no.1
    • /
    • pp.77-88
    • /
    • 2017
  • The concern on the greenhouse gas emissions is increasing globally. Especially, the greenhouse gas emission from fisheries is an important issue due to Cancun Agreements Mexico in 1992 and the Kyoto protocol in 2005. Furthermore, the Korean government has a plan to reduce the GHG emissions as 5.2% compared to the BAU in fisheries until 2020. However, the investigation on the GHG emissions from Korean fisheries has not been executed much. Therefore, the quantitative analysis of GHG emissions from Korean fishery industry is needed as the first step to find a relevant way to reduce GHG emissions from fisheries. The purpose of this research is to investigate which degree of GHG emitted from the major coastal fisheries such as coastal gillnet fishery, coastal dual purpose fishery, coastal pots fishery and coastal small scale stow net fishery. Here, we calculated the GHG emission from the fisheries using the LCA (Life Cycle Assessment) method. The system boundary and input parameters for each process level are defined for LCA analysis. The fuel use coefficients of the fisheries are also calculated according to the fuel type. The GHG emissions from sea activities by the fisheries will be dealt with. Furthermore, the GHG emissions for the unit weight of fishes are also calculated with consideration to the different consuming areas. The results will be helpful to understand the circumstances of GHG emissions from Korean fisheries.

Environmental Impact and Water Foot Print Assessment of Pot Bearing Using Life Cycle Assessment (LCA) (LCA를 이용한 교량용 포트받침 환경영향 및 물발자국 분석)

  • Park, Jihyung;Wie, Daehyung;Ko, Kwanghoon;Hwang, Yongwoo
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.38 no.6
    • /
    • pp.851-857
    • /
    • 2018
  • In this research, LCA analysis of the manufacturing process of pot bearing for fixed, movable in all directions, movable in one direction was carried out to analyze the environmental load using the LCA methodology. Especially, the water footprint that has been and issue in recent years was analyzed. As a result of LCA, it was analyzed that the contribution of the plate was more than 64.2% in all of the six impact categories in the case of fixed pot bearing base, and more than 94% in the category of resource depletion and photochemical oxidant creation. In the case of all direction pot bearing and one direction pot bearing, the contribution of PTFE was the highest in the global warming and stratospheric ozone depletion, and the contribution by the plate was higher in the other impact categories. The water footprint of each type of pot bearing was analyzed as $22.4m^3\;H_2O\;eq/kg$ for one direction pot bearing, $17.1m^3\;H_2O\;eq/kg$ for fixed pot bearing, and $14.1m^3\;H_2O\;eq/kg$ for all direction pot bearing. As a result of life cycle analysis, the contribution of water use in manufacturing was more than 65% in all three types. The results of this study can be used as basic data for decision making in construction method and material selection of bridges in the future.