• International conference on construction engineering and project management
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• 2022.06a
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• pp.179-187
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• 2022

The project performances can be measured in terms of meeting the project schedule, budget, and conformance to functional and technical specifications. Numerous studies have been conducted to examine the causes and effects of change orders for both vertical and horizontal construction, respectively. However, these studies mainly focus on a single project type, so this paper examines the impact of change order for cost growth and schedule overruns using four different building types to close the gap in the change order research area. A total of 211 building projects are collected from four building types: healthcare, residential, office, and education. Statistical analyses using ANOVA tests and linear regression models are used to examine the created metric $CO/day on the cost and schedule impacts. The results found that mean $CO/day values were not statistically different among building types, and that the sum of change orders is a statistically significant predictor of $CO/day. The results will help project stakeholders mitigate the negative change orders effects can be a challenge for project managers and researchers alike.

• Journal of Environmental Impact Assessment
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• v.27 no.4
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• pp.345-352
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• 2018

In order to establish mainstreaming of climate change adaptation in policy, plan, program or project, we set up three kinds of implementation methods. The first is preparation of new law(tentatively called "Act on Climate Change Response") and independent implementation, the second is preparation of new law and two kinds of implementation in existing Environmental Impact Assessment system, and the third is integrated assessment in Environmental Impact Assessment system without new legal base. And we analyzed merits and demerits of suggested schemes, and specific contents of each method. Furthermore, we suggested overview of contents of new law and revised Environmental Impact Assessment law and related regulations.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.622-624
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• 2015

As uncertain factors are latent in a construction project by nature, a change order occurs frequently. The occurrence of change orders in construction projects conducted during construction phase is known to cause unexpected negative impacts such as cost overrun, schedule delay, quality problem, and claims in the post-process. Thus, an efficient management method is necessary to prevent and minimize change orders during construction phase when they occur frequently. This paper analyzed the causes of change orders and the impact factors that occur during the construction phase of a construction project and suggested a direction for change order database building.

• Journal of Distribution Science
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• v.12 no.12
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• pp.5-17
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• 2014

Purpose - The purpose of this study is to examine the possible ways to minimize damage by analyzing the influence that may be exerted upon the business process of the distribution industry by unexpected climate change. Research design, data, and methodology - The optimum business process is to be implemented after dividing the diversified business process of the distribution industry into the four stages of the Business Continuity Plan (BCP). Results - First, the upper-level risks that would be impacted most sensitively by climate change have been selected. Second, the impact and characteristics of the environment have been discovered. Third, weighted values by criteria item of upper-level business risks have been analyzed. Fourth, it was possible to define the business priority order based on the individual and then to adjust the Recovery Time Objective (RTO). Conclusion - In this study, the priority order has been defined quantitatively by calculating the priority order score. Further, the priority order has been determined depending on whether any targeted business unit is applicable to the items of the business nature criteria.

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

• Journal of Climate Change Research
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• v.6 no.2
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• pp.121-131
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• 2015

As the temperature has changed by climate change, changes in its own characteristic values of the chemical substance or the movement and distribution of chemicals take place in accordance with the changes of hydrological and meteorological phenomena. Depending on the impact of climate change on the chemical behavior, it is necessary to understand and predict quantitative changes in the dynamics of the environment of pollutants due to climate change in order to predict in advance the occurrence of environmental disasters, and minimize the impact on the life and the environment after the incident. In this study, we have analysed and compared chemical fate models validated by previous studies in terms of model configuration, application size and input/output factors. The potential models applicable to municipal and industrial areas were selected on the basis of characteristic of each model, availability of input parameters and consideration for climate change, identified the problems, and then presented an approach to improve applicability.

• Journal of Environmental Health Sciences
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• v.42 no.6
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• pp.465-477
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• 2016

Objectives: This review examined the scientific evidence regarding the impact of climate change on food safety. Methods: The impact of climate change on food safety was assessed based on a survey of related publications reported in the past 20 years. The terms used for literature selection reflect three aspects: climate change; food; and food safety. Results: Climate change is expected to affect the key elements of food production - water and climate. These impact on food safety through many different pathways. Directly, food shortages according to the population grovoth result in a food security/food supply problem, These relationships are commonly understood. The indirect impacts include an increase in food-borne diseases and pathogens, increased mycotoxin production, and increased risk of pesticide residues in foods due to greater use of pesticides in response to warming and increased precipitation and the accompanying diseases in certain crops. Field studies and statistical and scenario analyses were performed to provide evidence. However, quantification of these relationships is still lacking. Conclusion: Adaptation measures at the local and community levels are essential since the pressures from weather and climate events may differ according to region and sector. It is recommended that we go beyond empirical observations of the association between climate change and food safety and develop more scientific explanations. We also need to explore alternative materials for bioenergy demands in order to improve sustainability.

• Journal of KSNVE
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• v.5 no.2
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• pp.247-256
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• 1995

In this paper, double exposure holographic interferometry using ruby pulse laser is formed in order to investigate the propagation of transient waves. The vibration characteristics according to the change of impact load direction, i.e., impacted in the shear direction and in the normal direction are analyzed. It was observed that the macroscopic trends of transient wave generation and propagation in the assembly of precipitator plates were almost similar regardless of the change of impact load direction. But the propagation and mixing of transient wave was advanced relatively slowly when impacted in the normal direction.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.371-375
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• 2015

Design-Build (DB) has gained in popularity in roadway projects due to its defining advantage to improve communication and fast-track project delivery. However, very little is known about the impact of change order frequency and occurrence timing pertaining to DB projects. The study analyzes their impacts on project time and cost performance by conducting a rigorous numerical analysis drawing on 530 3R (rehabilitation, reconstruction, and resurfacing) projects completed between 2002 and 2011 in Florida by using a multiple linear regression. The results indicate that DB outperformed Design-Bid-Build in project cost as well as time. Critically, the regression analysis signifies that earlier change order occurrence caused more unfavorable impacts on schedule and cost. The proposed analyses and models will lead to the improved ability of agencies to quickly and more reliably estimate the potential change order impacts on schedule and cost.

• International Journal of Highway Engineering
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• v.15 no.3
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• pp.65-74
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• 2013

PURPOSES: This study is to evaluate the dynamic modulus changes of permeable asphalt mixtures by using non-destructive impact testing method and to compare the dynamic moduli of permeable asphalt mixtures through repeated freezing and thawing conditions. METHODS: For the study, non-destructive impact testing method is used in order to obtain dynamic modulus of asphalt specimen and to confirm the change of dynamic modulus before and after freezing and thawing conditions. RESULTS : This study has shown that the dynamic moduli of asphalt concrete specimens consisting of 10%, 15% and 20% porosity are reduced by 11.851%, 1.9564%, 24.593% after freezing and thawing cycles. CONCLUSIONS : Non-destructive impact testing method is very useful and has repeatability. Specimen with 15% porosity has high durability than others.