• Korean Journal of Construction Engineering and Management
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• v.6 no.2 s.24
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• pp.111-119
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• 2005

Although the life-spans of most apartment buildings are over fifty years, they are often demolished and retrofitted only after twenty years, in spite of its remaining life expectancy, resulting in economical waste. The purpose of this paper is to estimate optimum remodeling period of apartment buildings using total cost. In this study it is seen that total sum of running cost of life-span on the buildings is about 4.69 times of initial cost till the fifty years of the life expectancy. The optimum remodeling period of the apartment building is thirty years applying the discount rate of $4.17\%$ and the discount rate should be $6.122\%$ to obtain the forty years of the optimum remodeling period. From the sensitivity analysis based on the change of the discount rates, it is seen that if discount rate decreases the optimum remodeling period can be extended, or vice versa. As a result, a time of the demolished and remodeling can be expected and the basic data can also be established for lengthening life-span of the apartment buildings.

• Korean Journal of Construction Engineering and Management
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• v.16 no.2
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• pp.12-20
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• 2015

The public employers are faced the mounting importance of decision process to settle the optimum VE delivery system of such public facilities buildings and etc. The elements of decision process of the public employer are formed in the various relationships of the concerned and when the projects are coming into effect, the decision process in the VE delivery method and the selection of contractor will be the name of the game. The decision process in the VE delivery method and the selection of contractor are created a case to be one and the same as well as initiates a consistency for the performance. However, the function and role of the public employer are projective accordingly to the organization of employer and the employer especially no system is equal to the capability of perfect evaluation and verification of the ability of the employer. Especially the lowest bidder policy that started with justification to increase the competitiveness and technical capability of the contractors through the completion in between contractors has been providing the hotbed for insolvency, irregularity and irrationality as a result. From this point of view it is declared that the buildup the edifice of supporting system in the process of decision to recover the mutual trust and respect of the concerned in the VE delivery system with the technostress and the systematization based on drawing the elements which affect the decision process of public employer.

• Korean Journal of Labor Studies
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• v.17 no.1
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• pp.297-323
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• 2011

Part-time jobs in Sweden are highly feminized yet are in fair conditions in terms of job security, earnings, and collective representation. Three points are considered to be important to understand why part-time work in Sweden carries such positive characteristics. First, the part-time work in Sweden is widely spread not as a result of employers' need for labor flexibilization but as means to enhance the work-life balance, a value pursued within a broader social policy package to change the breadwinner model. Second, discrimination against part-time workers is restrained in Sweden because the boundary between part-time and full-time is not conspicuous. Most of part-time jobs are occupied by regular workers who exert the right to part-time work, hence may go back to the full-time status any time. Third, the regulation on overtime work of part-time workers as well as full-time workers is strong. It is largely agreed among researchers that part-time work contributed greatly to an increase of female employment rate in Sweden. Since the 1970s, the increased availability of part-time jobs induced married women who used to be economically inactive to the labor market and maintained them to be economically active throughout the child rearing period. From the gender perspective, one may still raise issues regarding part-time work in Sweden such as persistent feminization and strong occupational sex segregation. However, the observed trend shows that the part-time work in Sweden has functioned more as a stepping stone to the full-time work for women than as a women's trap.

• Journal of the Korea Concrete Institute
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• v.23 no.5
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• pp.667-674
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• 2011

This paper discusses the analysis method of prestressed concrete girder integral abutment bridges for a 75-year bridge life and the development of prediction models for abutment displacements under thermal loading due to annual temperature fluctuation and time-dependent loading. The developed nonlinear numerical modeling methodologies considered soil-structure interaction between supporting piles and surrounding soils and between abutment and backfills. Material nonlinearity was also considered to simulate differential rotation in construction joints between abutment and backwall. Based on the numerical modeling methodologies, a parametric study of 243 analysis cases, considering five parameters: (1) thermal expansion coefficient, (2) bridge length, (3) backfill height, (4) backfill stiffness, and (5) pile soil stiffness, was performed to established prediction models for abutment displacements over a bridge life. The parametric study results revealed that thermal expansion coefficient, bridge length, and pile-soil stiffness significantly influenced the abutment displacement. Bridge length parameter significantly influenced the abutment top displacement at the centroid of the superstructure, which is similar to the free expansion analysis results. Developed prediction model can be used for a preliminary design of integral abutment bridges.

• Korean Journal of Construction Engineering and Management
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• v.21 no.3
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• pp.20-27
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• 2020

EPC contractors have made continuous efforts to develop integrated project execution methods to improve the performance of industrial plant project. In particular, the concept of Advanced Work Packaging (AWP) has been recently presented by readjusting the existing "Work Packaging" concept as part of the integrated project execution method from the project life-cycle perspective. However, Korean EPC contractors are still unfamiliar with the AWP implementation. Thus, this study aims to identify the organizational competency factor for effective implementation of AWP. For this purpose, first, this study identified the expected risks in AWP project and the 29 organizational competency factors to manage risks. Second, five experts verified the suitability of factors and supplemented the factors. Finally, 37 factors were identified as organizational competency factors for implementing AWP.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.6
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• pp.715-722
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• 2015

The prestressing force has not been managed after construction nevertheless it is one of the importrant factors that maintain the structural safety of PSC girder bridges. The prestressing force is just measured during construction using jacking device and after that, it can not be managed practically. For this reason, this study investigated the measurements of prestress using embedded sensors that can be available now with an ultimate goal to propose smart prestressed girders that can measure the prestress from the birth to the end of service life. 4 types of sensors were installed on the small prestressed girders, and the applicability and the accuracy of those sensors were tested while the prestress was applied to the girders. The results show that a center-hole type loadcell has a tendency to measure a prestressing force higher than a reference value, especially when it is loaded with an eccentricity. a EM sensor shows several advantages that has a good practical accuracy, that can be installed anyplace along the tendons.

• 한국노년학
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• v.39 no.2
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• pp.213-229
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• 2019

The purpose of this study was to examine various factors influencing the needs of Seoul's newly implemented outreach community services for older adults, and to suggest the direction of the outreach community health services in Seoul. A multi-level regression was conducted using data collected by face-to-face interviews from 1,000 individuals aged 65 and 70 in 17 districts, where participated in the Seoul's outreach community services. The results demonstrated that socioeconomic status (higher income and living alone), health status (having multiple chronic conditions and depression, lower health literacy), limited experience of the outreach community services, and low government trust at the individual level were associated with higher unmet need for the community outreach services. In addition, shorter participation period of the outreach services and financial independency at the district level were associated with higher unmet need for the services. The findings from this study implies the need for improving the quality of services by focusing on vulnerable groups such as individuals with lower income and worse health status. In addition, the outreach community health services may need to target individuals aged 66 to increasing efficiency of the services through utilizing results of life-cycle health checkup by the National Health Insurance Corporation.

• Korea journal of population studies
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• v.22 no.1
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• pp.123-151
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• 1999

미국사회에서 노인의 거주지 적응양식은 인종간에 차이가 크다. 일반적으로 소수인종노인은 백인 노인에 비하여 자녀와 함께 사는 경향이 강하다. 이에 대하여 문화적 입장에서는 소수인종은 백인에 비하여 가족부양규범이 강하다고 주장한다. 다른 한편 경제적 입장에서는 소수인종은 그들의 생애를 지배하는 빈곤 때문에 규모의 경제를 통하여 가계비용을 줄이기 위하여 확대가족을 유지할 수밖에 없다고 주장한다. 본 연구는 노인이 질병과 빈곤에 적응하는 방식에 있어 인종간 차이를 검토함으로써 기존의 경제학적 논의와 문화적 논의의 적합성을 검정하는데 목적을 두고 있다. 이를 위하여 노인의 거주지 적응에 대한 문화적 영향과 관련하여 두가지 가설을 검정하고 있다. 첫째, 소수인종 노인은 백인노인에 비하여 빈곤과 질병상황에서 가족으로부터 더 오랜기간 보호를 받는지를 검토한다. 둘째, 소수인종 노인은 백인노인에 비하여 건강이 악화될 때 더욱 신속하게 가족으로부터 보호를 받을 수 있는지를 검토한다. 분석을 위해서 1984년에서 1990년기간 동안 실시된 "고령화에 대한 종단적 조사(Longitudinal Survey on Aging)"를 이용하여 마르코비안 다중생명표 모형과 사건분석을 수행하였다. 본 연구결과에 따르면 소수인종 노인은 가족부양규범의 문화적 이점을 그다지 크게 다지고 있지 않다. 인종간 사망력과 시설입소의 차이를 통제할 때, 소수인종 노인은 백인노인에 비하여 보다 흔하게 자녀동거에서 단독거주형태로 혹은 그 반대방향으로 거주지 변화를 경험하고 있다. 백인 노인은 소수인종에 비하여 질병상태와 관련하여 자녀와 동거하는 경향이 더 강하다. 사망력과 시설입소의 인종간 차이를 통제할 때 소수인종노인이 백인노인보다 쉽게 자녀동거에서 단독거주로 이행하는데 이는 소수인종에서 가족부양체계가 불안정함을 의미한다. 또한 빈곤시에 소수인종 노인은 백인노인에 비하여 쉽게 자녀와 떨어져 살게 된다. 이러한 결과는 소수인종 노인에 대한 가족의 지원은 그 가족의 경제적 제약속에서 매우 안정적이지 못함을 시사한다. 못함을 시사한다.

• Korean Journal of Construction Engineering and Management
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• v.5 no.2 s.18
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• pp.181-193
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• 2004

A life cycle cost analysis model for public water supply systems should be different from the ones for other civil and architectural facilities as the operation and the maintenance cost of the water supply systems mainly come from the various mechanical systems and the pipeline systems of the collecting/treating/distributing facilities. This paper presents a cost classification scheme and a probabilistic life cycle cost analysis (PLCCA) model for public water supply systems. A value analysis (VA) procedure that is well suited for practical purposes is also presented. The presented probabilistic life cycle model and the value analysis procedure were applied to a real world project, and this case study is discussed in the paper. The model and the procedure presented in this study can greatly contribute to the value-oriented design alternative selection, the estimation of the maintenance cost, and the allocation of budget for water supply system construction projects.

• Korea Real Estate Review
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• v.28 no.2
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• pp.49-64
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• 2018

The purpose of this study is to analyze the effect of eco-friendly building certification grade on the price and cost of office in Seoul office building. For this purpose, multiple regression analysis is used to examine the prices of buildings. In order to identify the effect of environmental cost reduction of buildings with high eco-friendly certification, we also performed LCC (Life Cycle Cost) + LCA (Life Cycle Assessment) analysis. Results of our analysis show that office buildings with a higher level of eco-friendly certification are priced significantly higher. Through LCC analysis, it was also found that buildings with high levels of eco-friendly certification cost less than those with lower-level certification. Furthermore, it was confirmed that office buildings with higher-level environmental certification have total lower environmental load costs (TCA = LCC+LCA) than buildings without certification. According to the TCA analysis, buildings with a high level eco-certification generated lower social costs than buildings with lower-level or no certification.