• Structural Engineering and Mechanics
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• 제47권5호
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• pp.643-660
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• 2013

In the present work, the capacity ratings of steel truss bridges have been carried out incorporating dynamic effect of moving vehicles and its accumulating effect as fatigue. Further, corrosion in the steel members has been taken into account to examine the rating factor. Dynamic effect has been considered in the rating procedure making use of impact factors obtained from simulation studies as well as from codal guidelines. A steel truss bridge has been considered to illustrate the approach. Two levels of capacity ratings- the upper load level capacity rating (called operating rating) and the lower load level capacity rating (called inventory rating) were found out using Load and Resistance Factor Design (LRFD) method and a proposal has been made which incorporates fatigue in the rating formula. Random nature of corrosion on the steel member has been taken into account in the rating by considering reduced member strength. Partial safety factor for each truss member has been obtained from the fatigue reliability index considering random variables on the fatigue parameters, traffic growth rate and accumulated number of stress cycle using appropriate probability density function. The bridge has been modeled using Finite Element software. Regressions of rating factor versus vehicle gross weight have been obtained. Results show that rating factor decreases when the impact factor other than those in the codal provisions are considered. The consideration of fatigue and member corrosion gives a lower value of rating factor compared to those when both the effects are ignored. In addition to this, the study reveals that rating factor decreases when the vehicle gross weight is increased.

• KIEAE Journal
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• 제10권3호
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• pp.81-88
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• 2010

Current trend on sustainable tall building shows significant efforts on the integrated design approaches for the performative design to achieve efficient building for the energy, structural and materials. The design of tall buildings should take into consideration of environmental impact and economic benefits from sustainable approaches to ensure low energy consumption and CO2 emissions. Designing sustainable tall building require concerns and comprehensive understanding of sustainable building technology, sustainable rating system and supporting incentive policy. The research has been conducted on available rating system and the incentive policy for sustainable building design methodology through cases studies for this study. In the paper, author tried to emphasis the role of the incentive policy for the sustainable building and provides survey of the impact on rating, adaptable use of sustainable building technology on the current practice of tall building design.

• 아태비즈니스연구
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• 제13권4호
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• pp.79-89
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• 2022

Purpose - The purpose of this study was to examine the impact of ESG rating changes of companies listed in Korean Stock Exchange on stock returns. Design/methodology/approach - This study collected prices and ESG ratings of all the companies listed on the Korea Composite Stock Price Index. Based on yearly change of ESG ratings we grouped companies as 2 portfolios(upgrade and downgrade) and calculated portfolios' return. Findings - First, the difference in returns between upgraded and downgraded portfolios is small and statistically insignificant. Second, however, in the COVID-19 period (2020 ~ 2021), the upgraded portfolio outperforms the downgraded portfolio by 0.7 percentage points per month. The difference in returns between upgraded and downgraded portfolios is statistically significant after controlling for the Carhart four factors. Lastly, there are much higher volatility when the ESG rating changes are made of companies with low levels of ESG ratings. Research implications or Originality - This study is the first to examine the impact of ESG rating changes on stock returns in Korea. Furthermore, the findings can serve as a reference for managers who want to control a firm's risk by ESG rating changes. Practically, asset managers can use the findings to construct portfolios that are less risky or more profitable than the market portfolio.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.631-635
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• 2006

In this study, simplified methods on measurement and evaluation of heavy-wight impact sound was proposed due to provide easy quality control method to construction engineers. The simplified methods include using of rubber impact ball instead of bang machine, reduced number of measuring and impact positions which is prescribed as over 4 points, using of hand-held sound level meter as a frequency analyser and prediction equation for $L_{i.Fmax.AW}$, single number rating, using $L_{Amax}$, and $L_{Lmax}$ at each frequency band. The results showed that a method of boundary driving and boundary measuring is the most similar to the current rating method.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.111-112
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• 2013

Architecture has a large influence in the environment and human health. Therefore eco-friendly concept and sustainable development are important in Architectural field. This study aims to analyze impact of green building rating system on an apartment housing CO₂ emission using multiple regression analysis. But in this result, green building rating system has no effect on CO₂ emission. So, future study is required to analyze factors of green building rating system on the CO₂ emission.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.437-443
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• 2013

Recently, sustainable building design, a growing field within architectural design, has been emerged in the construction industry as the practice of designing, constructing, and operating facilities in such a manner that their environmental impact, which has become a great concern of construction professionals, can be minimized. A number of different green rating systems have been developed to help assess that a building project is designed and built using strategies intended to minimize or eliminate its impact on the environment. In the United States, the widely accepted national standards for sustainable building design are known as the LEED (Leadership in Energy and Environmental Design) Green Building Rating System. The assessment of sustainability using the LEED green rating system is a challenging and time-consuming work due to its complicated process. In effect, the LEED green rating system awards points for satisfying specified green building criteria into five major categories: sustainable sites, water efficiency, energy and atmosphere, materials and resources, and indoor environmental quality; and sustainability of a project is rated by accumulating scores (100 points maximum) from these five major categories. The sustainability rating process could be accelerated and facilitated by using computer technology such as BIM (Building Information Modeling), an innovative new approach to building design, engineering, and construction management that has been widely used in the construction industry. BIM is defined as a model-based technology linked with a database of project information, which can be accessed, manipulated, and retrieved for construction estimating, scheduling, project management, as well as sustainability rating. This paper will present a framework representing the building knowledge contained in the LEED green building criteria. The proposed building knowledge framework will be implemented into a BIM platform (e.g. Autodesk Revit Architecture) in which sustainability rating of a building design can be automatically performed. The development of the automated sustainability rating system and the results of its implementation will be discussed.

• 한국소음진동공학회논문집
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• 제14권7호
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• pp.626-631
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• 2004

In this study, the extracted words from the former study such as annoying, loud, noisy, irritating, disagreeable, strident, disturbed, and dissonant are given to subjects in psycho acoustic experiment lab. And then, correlation analysis between the words and floor impact noise rating method were carried out. As a result of this study followings are suggested ‘Annoying’ is the word most accurately expressing the subjects’ unpleasant feeling of domestic floor impact noise. The results of this study could be basic materials for psycho acoustic experiments for criteria on floor impact noise and Sound Classification on Floor Impact Sound Insulation Performance.

• 한국소음진동공학회논문집
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• 제20권1호
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• pp.66-73
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• 2010

Vehicles experience the impact due to harsh road conditions. Contact with a barrier on a road induces vehicles to vibrate, which brings about an impact sound. The attenuation of the impact sound is an important issue since passengers may complain about the impact noise. However, the perfect removal of impact noise is not possible as most of impact noise is caused by external conditions. It is thus necessary to make vehicles to possess more desirable sound quality characteristic of impact sound. More research is needed on objective attributes of impact sound; it is not a simple matter since impact noise is transient in nature and has a high level of sound at an instantaneous moment. A new objective attribute of impact noise is designed by using wavelet transform. Wavelet transform is appropriate for the analysis of transient signals such as impact noise. The usefulness of new objective attribute, which is a sound metric, is examined by comparison with the mean subjective rating for real impact noise of passenger cars. The new sound metric has better correlation with the mean subjective rating than already existing sound metrics

• KIEAE Journal
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• 제10권5호
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• pp.139-150
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• 2010

Until now, the eco-friendly construction (green construction) has been focused on reducing environmental impacts in use(operation and maintenance) phase. Considering the environmental influence along the life cycle of construction project, the impact in execution phase is rather lower than that in use phase. However, that impact is thought to be greatly decreased by well-organized activities. Based on its urgency and requirement for timely action, this study aimed to discuss the greenhouse gas (GHG) reduction plan in execution phase from a broad perspective. To achieve this purpose, the green building rating systems in domestic and foreign countries have been reviewed, and the practice in Japan was investigated. In order to improve current on-site greenhouse gas management, the integration among construction phases, participants, and environmental factors, and institutional supports are required as well as the contractor's efforts.

• 한국구조물진단유지관리공학회 논문집
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• 제21권4호
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• pp.69-79
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• 2017

표준 중량 충격원의 실제 충격원 재현성에 대한 논란이 있음에도 현재 기준에서는 뱅머신 방식만 사용하고 있다. 현행 기준의 평가방법 및 등급 기준이 충격원 특성을 고려하지 못하고 있어 충격원의 선택에 따라 바닥충격음 차단 성능 등급에 차이가 발생하기 때문이다. 본 연구는 충격원 특성 외에 바닥 진동 거동 특성을 함께 고려한 현행 기준의 바닥충격음 평가 방법 고찰을 목적으로 한다. 공동주택 mock-up 실험동에서 표준 중량 충격원과 실충격원에 대하여 바닥충격음을 측정하고 이를 이용하여 해외 평가 방법과 우리나라의 평가 방법을 비교 검토하였다. 또한 현행 바닥충격음 평가 기준의 대상 주파수 범위를 벗어나는 저주파수 대역의 음압레벨은 네텔란드의 저주파 소음 인지 곡선과 국내 연구자가 제안한 저주파 소음 기준안을 이용하여 평가하였다. 그 결과 기준 및 평가 산정 방법에 따라 성능 평가 결과가 상이하며, 바닥 진동의 지배 주파수 범위에서 모든 충격원에 대한 바닥충격음 가청 소음으로 인식하여 성가시게 느낄 가능성이 매우 크다. 현행 평가 기준의 단일수치 평가량 산정 방법은 충격원에 따라 상이한 음압레벨 스펙트럼 특성을 제대로 반영하지 못하며, 바닥의 진동 거동 지배 주파수를 포함하는 저주파수 대역의 음압레벨을 고려하지 않고 있어 바닥충격음에 대한 평가 결과와 사람의 인지 수준에 차이가 발생할 수 있다. 따라서 충격원에 따른 음압레벨의 스펙트럼 특성과 저주파수 대역의 음압레벨을 반영할 수 있도록 현행 기준의 평가 방법을 보완할 필요가 있다.