• Journal of Korean Neurosurgical Society
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• 제60권3호
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• pp.322-326
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• 2017

Neuroendoscopic surgery is performed because it causes minimal damage to normal structures, carries a lower rate of complications, and achieves excellent outcomes. Surgeons using an endoscope and related instruments can perform complex operations through very small incisions, which is especially useful for minimally invasive procedures for the brain and spine. Neuroendoscopic surgery is now performed in cases of obstructive hydrocephalus, various intraventricular lesions, hypothalamic hamartomas, craniosynostosis, skull base tumors, and spinal lesions. This review discusses the brief history of neuroendoscopy and the current state and future perspectives of endoscopic surgery.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제22권2호
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• pp.83-97
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• 2019

Science, Technology, Engineering, and Mathematics (STEM) education has been at the forefront of K-12 curricula in the technology-rich 21st century, with emphasis on how these fields reinforce each other in preparing students for a dynamic future. However, there is a need for greater attention to STEM education research in the mathematics education community, in particular to pedagogical approaches that facilitate integrating the mathematics component of STEM education. Toward this end, the authors report the outcomes of a Project-based Learning (PBL) unit in which upper elementary students integrated STEM elements by researching, crafting, testing, and evaluating kites they created by applying scientific knowledge of aerodynamics and mathematical knowledge of polygons, surface area, graphs, and data analysis. This unit, which the authors developed, implemented, and assessed, demonstrates how STEM subjects and in particular mathematics can be effectively integrated in upper elementary school classrooms through PBL.

• 국제학술발표논문집
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• The 2th International Conference on Construction Engineering and Project Management
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• pp.820-829
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• 2007

This paper presents an evaluation of feasibility studies conducted to justify investments in infrastructure projects. An analysis of a previous feasibility study for a highway construction project is presented in this paper with an emphasis on the estimates and forecasts presented in that study in order to weigh expected benefits from the project against expected costs. The forecasted numbers are compared with actual data collected during the operation phase about the usage of the facility. The comparison reveals a huge difference between estimated numbers and actual numbers. Based on the lessons learned from the analyzed case study, recommendations are presented to improve feasibility studies for infrastructure projects including: peer review of feasibility studies; before-and-after feasibility studies; and defined scope and methodology for feasibility studies. Decision makers are advised to take outcomes of feasibility studies for infrastructure projects with extreme caution as some studies may provide erroneous and misleading input to their decisions regarding investment in infrastructure projects.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.791-795
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• 2005

A simulation model is proposed to evaluate the effect of correlations between activity durations on the overall project duration. The proposed model incorporates NORTA, a recent developed statistical method, into the simulation process to allow arbitrarily specified marginal distributions for activity durations and any desired correlation structure. The generality is of practical value when systematic data is not available and planners have to rely on arbitrary experts' estimation, which may involve a mixed situation when some activity durations are continuously distributed whereas others are discrete outcomes. The proposed model is validated by showing that the correlation coefficients of the simulation results are close to the originally specified ones. The simulation results are compared to two conventional approaches: PERT and simulation without correlation. The comparisons illustrate that the proposed model can provide important management information, which would otherwise be distorted due to the neglect of the correlations between activity durations.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.18-24
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• 2022

State highway agencies (SHAs) typically apply a competitive procurement procedure to select contractors for their design-bid-build projects. Since the level of competition affects construction bid prices and project outcomes, the Federal Highway Agency (FHWA) suggests SHAs seek ways to improve competition among contractors continuously. However, they rarely conduct an empirical assessment of the current competition level necessary to identify room for improvement. Besides the number of bidders on a project, other factors such as winning or losing rates among the contractors in previous projects can also indicate the degree of competition; only a few contractors may have won the majority of the projects in a specific region. However, few studies have investigated such factors. This paper proposes a network analysis-based approach to evaluating contractor competition levels of highway projects using historical bid tabulation data. The proposed method provides insights into overall competition levels, the determination of competitive contractors, and winning rate distribution among contractors.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.711-716
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• 2011

Ministry of Land, Transportation and Maritime Affairs of Korea has started a research project on verification process and safety assessment of Communication Based Train Control (CBTC) system for metropolitan railroad control as a 3-year project starting from 2010. As a number of companies has made efforts in securing the technologies for domestic production of CBTC systems, the purpose of the project is to develop the specification for interoperability with the considerations for local environments including metropolitan train operations and wireless communications. And the developed systems and the RAMS related outcomes from the participating companies are subject to Independent Safety Assessment (ISA) performed by a foreign specialized agency and the corresponding certificates are to be issued as a part of the project. In this paper, the RAMS management for verification and commercialization of metropolitan railroad CBTC systems has been studied. The study includes response strategy for the requirements of international standards, responsibility and authority of the related institute and the companies, quantitative RAMS objectives, and risk management strategies in project fulfillment.

• 농촌계획
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• 제19권2호
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• pp.107-120
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• 2013

A lot of rural development projects have been planned and implemented for revitalizing rural areas in South Korea. However, it is not easy to properly evaluate and quantitatively analyze project outcomes. For this reason only selected regions have been evaluated for rural projects by government agencies. In this study, we analyzed the purpose and the contents of the Rural Village Development Project (RVDP) and Green Tourism Village Project (GTVP) to find indicators for evaluating results of rural projects using logistic regression analysis. Outputs of this study show that RVDPs increase regional population and GTVPs positively affect the sales of agricultural products. We also estimated the spatial distribution of project effects through spatial autocorrelation analysis and local-spatial autocorrelation analysis. Results show that the Moran's I values for the proportion of farmers with avocational jobs, product sales changes, and population growth in Jeol-La province are positive and the biggest one is population growth. Especially, key areas of agricultural product sales are widely distributed.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.628-634
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• 2009

It is a common practice in Hong Kong for the main contractors of local building projects to sublet most of the work to subcontractors. Consequently their roles have gradually transformed from a constructor to a manager of subcontractors. The outcomes of a project therefore depend heavily on the subcontractors' performance. However, most of the subcontractors complain that they are unable to efficiently and effectively operate due to site coordination problems, such as inaccurate site reference lines, caused by main contractors. The site problems may consume significant amounts of resources if practical solutions cannot be agreed by the project participants early enough. Rahim Organizational Conflict Inventory-II (ROCI-II) model was developed by M.A. Rahim that measure five types of conflict management style including Integrating, Obliging, Dominating, Avoiding and Compromising. This paper presents the questionnaire survey based on the ROCI-II model to rank the preference on the conflict management style adopted by the project representatives of the subcontractors in handling the site coordination problems and its impact to the time used to agree the solutions to the different types of site coordination problems with main contractor. The survey results show that most of the subcontractors' project representatives preferred to adopt the Compromising style to tackle the site coordination problems and the time used to agree the solutions with main contractor was influenced by the conflict management style adopted.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.774-779
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• 2005

Client requirements is a concept with increasing interest in relation to several outcomes of companies, and in particular, in the event of apartment project that takes large share in the domestic construction industry, diverse angle of survey is performed to discover the client requirements and reflect them to the project to improve the quality. For this purpose, it is required to learn the client requirements and apply it in the apartment project, and the QFD (Quality Function Deployment) linked ROQ (Return On Quality) is a technique used in the manufacturing that surveys the client requirements to improve the customer satisfaction, and apply it to the quality improvement program to improve the profitability in this process. In this study, through the application of the ROQ process, the plan to improve the apartment quality management is presented. For this purpose, the consumer interview survey, FGI (focus group interview) survey and the client requirements are analyzed, and thereafter, through the interview with the specialist, the quality improvement program that enables the application to the product development of new apartment product is established. Through this process, the new apartment quality management improvement plan is presented.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.608-615
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• 2013

The major countries including Korea extend the national investment on R&D and implement the business performance diffusion policy as the knowledge based competition age arrives recently. The necessity for risk management and systematic management system for R&D achievement have been appeared to prevent the failure as the R&D scale becomes larger as it was said. For this matter, the organization such as NASA and DoD in USA defines the Technology Readiness Level (TRL) as a quantitative accomplishment management index and utilize the Technology Readiness Assessment (TRA) system as a criterion. Such tool is evaluated as very effective in the R&D project purposed the practicalization. It is expected that the disadvantage of evaluation system which is oriented to the academic accomplishment in its contents of current research and to contribute greatly to the practicalization of outcomes when such technology readiness level concept is applied to Korean national construction and transportation R&D project. Accordingly, this study analyzed the concept of TRL·TRA, the characteristics and current evaluation management system of Korean national construction and transportation R&D project and suggested the construction and transportation R&D project TRL·TRA performance model to accomplish the practicalization purpose.