• International conference on construction engineering and project management
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• 2015.10a
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• pp.58-59
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• 2015

As the business environment for construction enterprises has been worse, the level of their dependence on public projects increases. Under these circumstances, the public owners should pursue more efficient management process and make continuous efforts to establish strategic project-oriented organizations. There are growing concerns on owners' role with the recognition that the public owners are the key stakeholders to improve effectiveness in public sectors and reinforce competitiveness of entire industry. This study reviewed the characteristics of public construction projects with the concept of program, evaluated the current status of program management capabilities, and discussed the requirement for effective program management.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.203-211
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• 2009

Korean public owners who order public multi-family housing construction projects have yet to gain access to a model for predicting construction cost. For this reason, their construction cost prediction is mainly dependent upon historic data and experience. In this paper, a cost-prediction model based on Case-Based Reasoning (CBR) in the design phase of public multi-family housing construction projects was developed. The developed model can determine the total construction cost by estimating the different Building, Civil, Mechanical, Electronic and Telecommunication, and Landscaping work costs. Model validation showed an accuracy of 97.56%, confirming the model's excellent viability. The developed model can thus be used to predict the construction cost to be shouldered by public owners before the design is completed. Moreover, any change orders during the design phase can be immediately applied to the model, and various construction costs by design alternative can be verified using this model. Therefore, it is expected that public owners can exercise effective design management by using the developed cost prediction model. The use of such an effective cost prediction model can enable the owners to accurately determine in advance the construction cost and prevent increase or decrease in cost arising from the design changes in the design phase, such as change order. The model can also prevent the untoward increase in the duration of the design phase as it can effectively control unnecessary change orders.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.2
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• pp.1043-1063
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• 2019

With delegating proxy to process data before outsourcing, data owners in restricted access could enjoy flexible and powerful cloud storage service for productivity, but still confront with data integrity breach. Identity-based data auditing as a critical technology, could address this security concern efficiently and eliminate complicated owners' public key certificates management issue. Recently, Yu et al. proposed an Identity-Based Public Auditing for Dynamic Outsourced Data with Proxy Processing (https://doi.org/10.3837/tiis.2017.10.019). It aims to offer identity-based, privacy-preserving and batch auditing for multiple owners' data on different clouds, while allowing proxy processing. In this article, we first demonstrate this scheme is insecure in the sense that malicious cloud could pass integrity auditing without original data. Additionally, clouds and owners are able to recover proxy's private key and thus impersonate it to forge tags for any data. Secondly, we propose an improved scheme with provable security in the random oracle model, to achieve desirable secure identity based privacy-preserving batch public auditing with proxy processing. Thirdly, based on theoretical analysis and performance simulation, our scheme shows better efficiency over existing identity-based auditing scheme with proxy processing on single owner and single cloud effort, which will benefit secure big data storage if extrapolating in real application.

• Journal of Communications and Networks
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• v.16 no.6
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• pp.592-599
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• 2014

Cloud computing enables users to easily store their data and simply share data with others. Due to the security threats in an untrusted cloud, users are recommended to compute verification metadata, such as signatures, on their data to protect the integrity. Many mechanisms have been proposed to allow a public verifier to efficiently audit cloud data integrity without receiving the entire data from the cloud. However, to the best of our knowledge, none of them has considered about the efficiency of public verification on multi-owner data, where each block in data is signed by multiple owners. In this paper, we propose a novel public verification mechanism to audit the integrity of multi-owner data in an untrusted cloud by taking the advantage of multisignatures. With our mechanism, the verification time and storage overhead of signatures on multi-owner data in the cloud are independent with the number of owners. In addition, we demonstrate the security of our scheme with rigorous proofs. Compared to the straightforward extension of previous mechanisms, our mechanism shows a better performance in experiments.

• Nutrition Research and Practice
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• v.10 no.6
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• pp.635-640
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• 2016

BACKGROUND/OBJECTIVES: This study was conducted to evaluate the feasibility of a sodium reduction program at local restaurants through nutrition education and examination of the health of restaurant owners and cooks.SUBJECTS/METHODS: The study was a single-arm pilot intervention using a pre-post design in one business district with densely populated restaurants in Seoul, South Korea. The intervention focused on improving nutrition behaviors and psychosocial factors through education, health examination, and counseling of restaurant personnel. Forty-eight restaurant owners and cooks completed the baseline survey and participated in the intervention. Forty participants completed the post-intervention survey. RESULTS: The overweight and obesity prevalences were 25.6% and 39.5%, respectively, and 74.4% of participants had elevated blood pressure. After health examination, counseling, and nutrition education, several nutrition behaviors related to sodium intake showed improvement. In addition, those who consumed less salt in their baseline diet (measured with urine dipsticks) were more likely to agree that providing healthy foods to their customers is necessary. This study demonstrated the potential to reduce the sodium contents of restaurant foods by improving restaurant owners' and cooks' psychological factors and their own health behaviors. CONCLUSIONS: This small pilot study demonstrated that working with restaurant owners and cooks to improve their own health and sodium intake may have an effect on participation in restaurant-based sodium reduction initiatives. Future intervention studies with a larger sample size and comparison group can focus on improving the health and perceptions of restaurant personnel in order to increase the feasibility and efficacy of restaurant-based sodium reduction programs and policies.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.119-124
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• 2006

Design-Build, one contractor is responsible for both the design and construction, has become more popular since the government framed the policy on how to activate the design-build projects in 1996. The reality is, however, there are many problems encounted on Contractor Selection Method for Public Design-Build Projects. The purpose of this paper is to improve the problems, no way to meet the goal(value) the owners expect from the design-build projects, for instance, not fully reflecting the characteristics of projects and owners intention, not systematical enough to judge if bidders could carry out the contract. This study will insist we introduce Best Value Procurement, which is being commonly used in some advanced countries recently, so that we would properly select the contractor suitable for Best Value concept which totally depends on the owners, types of work and specified conditions. Furthermore, by passing through the Two-Step Procedures following Pre-qualification in Best Value Procurement, we expect it lighten the bidders' burden for proposal and the owners' complicate bid administration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.7430-7437
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• 2014

Owing to the increase in large and complex construction projects, the design paradigm of architecture and civil engineering projects has changed from 2D CAD to 3D CAD. For this reason, to meet the strong requirements of project contractors, various efforts have been made to adopt a Building Information Modeling (BIM) technology for effective construction management. On the other hand, compared to architectural projects, only a few civil engineering project cases have been conducted in the perspective of public contractors. This is because the characteristics of civil project contractors and the negative pursuit of adopting BIM technology due to the lack of a current BIM system and technologies. Recently, positive changes in adopting BIM technology for public projects were anticipated by public owners, such as the Public Procurement Service and the Ministry of Land, Infrastructure and Transport. In this regard, this study analyzed the current BIM technology status of public owners in Korea to adopt the BIM policies and guidelines of the Korean government. Strategies for adopting BIM technologies for Korean public owners are also discussed based on an analysis of civil engineering BIM project cases.

• KDI Journal of Economic Policy
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• v.33 no.3
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• pp.121-161
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• 2011

We study incentive structures of public developers and land owners in the process of public expropriations using a sequential game model. In the model, we show that there is an incentive for the public developer to give more compensation than just compensation that are defined by law. Also the model shows that there is an incentive for the land owners to revolt strategically against the public expropriation. Then an ideal authority delegation model is introduced to resolve the problems, where an independent appraiser determines the compensation for the expropriation. In the real world, improving the independence of appraisal process is critical to make the system closer to the ideal authority delegation model. So this paper concludes by making a few policy suggestions to improve the current appraisal system.

• Korean Architects
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• s.649
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• pp.116-117
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• 2023

• Korean Journal of Computational Design and Engineering
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• v.20 no.3
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• pp.269-280
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• 2015

Although BIM has been recognized as one of the main streams that advance the construction industry worldwide, it is difficult to ensure the quality of BIM data due to the problems such as internal errors of BIM tools and lack of guidelines that enhance design quality. Such problems cause designers, constructors, and project owners to hesitate applying it to their business. The main objective of this research is to develop a BIM guide for public project owners that is to be usable at the design phase of the public projects. To meet the objective, the study invited 10 BIM experts from Korean construction industry and operated workshops with focus group interview methodology. As well, a number of BIM guidelines from the BIM advanced countries were reviewed to identify valuable contents for the guide. There are four main parts in the guide developed: BIM design procurement process guide, Request for Proposal development guide for BIM design, BIM execution plan development and evaluation guide, and BIM output and deliverables review and evaluation guide.