• Korean Journal of Construction Engineering and Management
• /
• v.6 no.5 s.27
• /
• pp.69-77
• /
• 2005

Change is inevitable and is a reality of construction projects. Most construction contracts include change clauses and allowing contractors an equitable adjustment to the contract price and duration caused by change. However, the actions of a contractor can cause a loss of productivity and furthermore can result in disruption of the whole project because of a cumulative or ripple effect. Because of its complicated nature, it becomes a complex issue to determine the cumulative impact (ripple effect) caused by single or multiple change orders. Furthermore, owners and contractors do not always agree on the adjusted contract price for the cumulative Impact of the changes. A number of studies have attempted to quantify the impact of change orders on project costs and schedule. Many of these attempted to develop regression models to quantify the loss. However, regression analysis has shortcomings in dealing with many qualitative or noisy input data. This study develops ANN models to classify and quantify the labor productivity losses that are caused by the cumulative impact of change orders. The results skew that ANN models give significantly improved performance compared to traditional statistical models.

• Journal of Environmental Impact Assessment
• /
• v.17 no.5
• /
• pp.299-309
• /
• 2008

Cumulative effects can be defined as impacts on environment which results from incremental impacts of a proposed project, which covers other past, present, and reasonably foreseeable future actions. The necessity of Cumulative Effect Assessment is that, when there are several projects near the project area, environmental effects of individual project can be larger or smaller than those of individual project without having projects nearby because of synergy, ascending and descending effects. This study was intended to help Environmental Impact Assessment practitioners identify spatial and temporal boundaries during the scoping stage. To do this, literature review of domestic and foreign legislations, guidelines, textbooks and papers related to Environmental Impact Assessment and Cumulative Effect Assessment was accomplished. This study suggests that continuous research be needed in order to identify spatial boundaries for other assessment fields and to develop methodologies for cumulative effect assessment.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.15 no.3
• /
• pp.29-34
• /
• 2007

Numerical analyses are carried out to evaluate the cumulative impact damage of an automotive front end bumper under the low speed crash events(CMVSS215) by using explicit code. Results of first impact simulation, which are deformed shape, thickness, stress tensors and strain tensors, are used as the initial conditions for a next impact simulation. Between the events, the residual vibration is damped out by using nodal damping, and then recovery after each event is evaluated by several methods, one of which is a springback analysis with implicite finite element analysis code. The coupled analysis scheme for the evaluation of cumulative impact damage is verified through the comparison with test results.

• Korean Journal of Construction Engineering and Management
• /
• v.7 no.2 s.30
• /
• pp.171-180
• /
• 2006

Change is inevitable and is a reality of construction projects. Most construction contracts include change clauses and allowing contractors an equitable adjustment to the contract price and duration caused by change. However, the actions of a contractor can cause a loss of productivity and furthermore can result in disruption of the whole project because of a cumulative or ripple effect. Because of its complicated nature, it becomes a complex issue to determine the cumulative impact (ripple effect) caused by single or multiple change orders. Furthermore, owners and contractors do not always agree on the adjusted contract price for the cumulative impact of the changes. A number of studies have attempted to quantify the impact of change orders on project costs and schedule. Many of these attempted to develop regression models to quantify the loss. However, regression analysis has shortcomings in dealing with many qualitative or noisy input data. This study develops ANN models to classify and quantify the labor productivity losses that are caused by the cumulative impact of change orders. The results show that ANN models give significantly improved performance compared to traditional statistical models.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.9 no.6
• /
• pp.107-116
• /
• 2006

Recently, it has been important not only to evaluate environmental effects but also to assess cumulative and comprehensive effects by the development projects. This paper concentrates on temporal and spatial cumulative impacts on Suji district in Yongin, Gyunggi-do. This paper adopted two methods to assess the cumulative impacts. First, it assesses the temporal change of forest patch size and land cover according to the patch size. Second, it compares housing development zones with the neighborhood. The result of the research appears that the damage is very serious, especially in small forest. The Forest area is changed to farm land, most of them become to built-up area later. In addition, it is assessed that the secondary housing development projects did more harm than the initial one. By assessing the cumulative impacts on Suji district, this research suggests to minimize two kinds of solutions : comprehensive environmental assessments in regional unit and regulation on total forest quantity.

• Journal of Environmental Impact Assessment
• /
• v.9 no.4
• /
• pp.277-290
• /
• 2000

The purpose of this study is to identify the problems of environmental impact assessment(EIA) and to suggest new EIA technology. The problems of EIA in Korea can be summarized as follows. First, the EIA does not reflect the impact of policy, plan and program on environment. Second, the project EIA does not consider the cumulative impacts such as additive impacts, synergistic impacts, threshold/saturation impacts, induced and indirect impacts, time-crowded impacts, and space-crowded impacts. Third, the EIA techniques in Korea are not standardized. Finally, the present EIA suggests only alternatives to reduce adverse impacts. To solve above-mentioned problems, the development of new EIA technology is essential. First, the new EIA technology should be developed toward pollution prevention technology and comprehensive and integrated environmental management technology. Second, new fields of EIA for pollution prevention contain strategic environmental assessment, cumulative impacts assessment, socio-economic impact assessment, cyber EIA and EIA technology necessary after the reunification of Korean Peninsula. Third, EIA technology for integrated environmental management contains the development of integated environment assessment system and the development of packaged EIA technology. The EIA technology for integrated environmental assessment system contains (1) development of integrated impact assessment technology combining air/water quality model, GIS and remote sensing, (2) integrated impact assessment of EIA, traffic impact assessment, population impact assessment and disaster impact assessment. (3) development of integrated technology combining risk assessment and EIA (4) development of integrated technology of life cycle assessment and EIA, (5) development of integrated technology of spatial planning and EIA, (6) EIA technology for biodiversity towards sustainable development, (7) mathematical model and GIS based location decision techniques, and (8) environmental monitoring and audit. Furthermore, there are some fields which need packaged EIA technology. In case of dam development, urban or industrial complex development, tourist development, landfill or combustion facilities construction, electric power plant development, development of port, road/rail/air port, is necessary the standardized and packaged EIA technology which considers the common characteristics of the same kind of development project.

• Journal of Environmental Health Sciences
• /
• v.46 no.1
• /
• pp.22-34
• /
• 2020

Objectives: Based on the concept of environmental justice, we developed an evaluation model for setting and adopting the direction of environmental health policy using environmental health indicators and statistics from the local governments of Seoul, including environmentally susceptible populations. Methods: We selected a total of 20 variables based on data officially released from national and local governments. After the classification of these variables into the five components of environmental pressure, environmental status, environmental disease, sensitive population, and socioeconomic status, a basic model was constructed to calculate the relative scores of the local governments. Results: The cumulative impact scores for assessment of environmental health status were similar to those of the environmental pressure and status components. The highest five cumulative impact scores fell between 114 and 147. Local government A reported the highest scores and had high environmental pressure, environmental status and socioeconomic status. In addition, the evaluation of the other four local governments indicated that they exhibited above average scores for environmental pressure and environmental status, two did so for environmental disease, and four for sensitive population. Conclusion: We constructed a model to evaluate the environmental health status of the local governments of Seoul based on cumulative impact scores under the concept of environmental justice. As an approach for studying environmentally vulnerable areas through relative ranking, this model was feasible for policy-setting. In addition, this approach would be an analytically useful tool for decision-makers.

• Journal of Environmental Impact Assessment
• /
• v.30 no.6
• /
• pp.413-424
• /
• 2021

Health impact assessment in the environmental impact assessment is conducted to determine whether to exceed the standard of each single substance and to establish appropriate reduction measures. In some development projects, although all substances in risk assessment meet the standard, exposure concentration is very close to it. However, considering the cumulative exposure of all substances, health effects are likely to occur considerably severer than those of individual substances, so it is necessary to prepare a concrete and improved methodology for integrating evaluation of emissions to identify the health effects actually exposed to receptors of living things. This study established the definition of cumulative risk assessment through overseas advanced cases and domestic and foreign literature reviews, and proposed a methodology for utilizing cumulative risk assessment considering health effects on multiple substances when developing industrial complexes. Applied by the proposed methodology, integrated indicators forfourtypes of hazardous heavy metals (Ni, Cr⁶⁺, Cd, As) emitted from industrial complexes were calculated, and applicability was tested with case of the industrial complex development projects conducted over the last decade (2011-2020).

• Journal of the Korean association of regional geographers
• /
• v.20 no.4
• /
• pp.444-453
• /
• 2014

Inequality of environmental impact is forecast to deepen due to the damage of environmental risk by the interaction between environmental and social inequalities causing more harms to environmentally vulnerable population. This study assessed the integrated cumulative impact of Seoul using Environmental Health Screening Tool developed by Environmental Protection Agency of California. In order to screen vulnerable area to environmental health, 10 indexes have been selected according to the environmental burden of exposure to environment and public health effects, population characteristics of sensitive populations and socio-economic factors. As a result of assessment conducted on cumulative impact of Seoul for years 2009~2011 through Environmental Health Screening Tool, risk factor for districts of Gangseo and Gangnam of Seoul showed high - Gangseo area indicated high risk factor both in environmental burden and population characteristics, while Gangnam area appeared high in environmental burden. The result of survey will be able to suggest scientific basis to push through fair and effective environmental policy in consideration of environment vulnerable population.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.3D
• /
• pp.363-369
• /
• 2008

Change is inevitable and is a reality of construction projects. Change adjustment includes the cost associated with materials, labor, etc. However, the actions of a contractor can cause a loss of productivity and furthermore can result in disruption of the whole project because of a cumulative or ripple effect. Because of its complicated nature, it becomes a complex issue to determine the cumulative impact (ripple effect) caused by single or multiple change orders. Furthermore, owners and contractors do not always agree on the adjusted contract price for the cumulative impact of the changes. What is needed is a reliable method to identify and quantify the loss of productivity caused by cumulative impact of change orders. This study survey the change orders data in domestic area for public construction and analyze to quantify change order impact. This study developed concepts of "%CO", "%Delta", "%T" to capture change order effect on project and search the relationships between them. Finally, this study find strong relationship between change order and loss.