• Title/Summary/Keyword: impact rating

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Rating of steel bridges considering fatigue and corrosion

  • Lalthlamuana, R.;Talukdar, S.
    • Structural Engineering and Mechanics
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    • v.47 no.5
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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.

A Study on Sustainable Tall Building by Rating System and Incentive Policy through Case Study (해외사례조사를 통해 본 친환경 인증 초고층 빌딩과 인센티브정책에 관한 연구)

  • Kim, Hyeong Il;Shin, Sung Woo
    • KIEAE Journal
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    • v.10 no.3
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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.

A Study on Responsible Investment Strategies with ESG Rating Change (ESG 등급 변화를 이용한 책임투자전략 연구)

  • Young-Joon Lee;Yun-Sik Kang;Bohyun Yoon
    • Asia-Pacific Journal of Business
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    • v.13 no.4
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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.

Simplified method on measurement and evaluation of floor impact sound using impact ball (임팩트 볼에 의한 바닥충격음 측정 및 평가 간편법)

  • Kim, Yong-Hee;Lee, Sin-Young;Jeon, Jin-Yong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.11a
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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.

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Impact of Green Building Rating System on an Apartment Housing CO2 Emission using Multiple Regression Analysis (다중 회귀 분석을 이용한 친환경 건축물 인증제도가 공동주택 CO2 발생량에 미치는 영향 분석)

  • Jung, Jung-Hee;Ryu, Hyeok-Jun;Lee, Jong-Hun;Kim, Ju-Hyung;Kim, Jae-Jun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2013.05a
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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.

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A Framework of Building Knowledge Representation for Sustainability Rating in BIM

  • Shahaboddin Hashemi Toroghi;Tang-Hung. Nguyen;Jin-Lee. Kim
    • International conference on construction engineering and project management
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    • 2013.01a
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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.

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A Study on the Proper Vocabularies for Evaluating Floor Impact Sound in Apartment Houses Considering Rating Methods (평가방법을 고려한 공동주택 바닥충격음 평가어휘 선정에 관한 연구)

  • 이재연;김선우;송민정
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.14 no.7
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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.

Sound Metric for the Impact Sound of a Car (자동차 임팩트 소음에 대한 음질 요소 개발)

  • Park, Sang-Won;Kim, Ho-Wuk;Na, Eun-Woo;Lee, Sang-Kwon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.20 no.1
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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

Greenhouse Gas Management Policy during Construction Execution Phase -Focused on Green Building Rating Systems and Japanese Case- (건축물 시공단계에서의 온실가스 배출 관리 방안 -국내외 친환경 인증제도와 일본 현장의 대응 방안을 중심으로-)

  • Song, Sang Hoon
    • KIEAE Journal
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    • v.10 no.5
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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.

Consideration on Rating Method for Heavy Impact Sound Taking Account of the Characteristics of Floor Vibration and Impact Sources (바닥 진동 거동 및 충격원 특성을 고려한 바닥 중량 충격음 평가방법 고찰)

  • Lee, Min-Jung;Choi, Hyun-Ki
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.21 no.4
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    • pp.69-79
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    • 2017
  • The purpose of this study is to reconsider the rating method for the floor impact sound insulation performance in current criterion. Although there are some arguments about proper standard heavy impact source with reproducibility of actual impact source in residence building, bang machine is adopted as the only standard heavy impact source in domestic criterion. To inspect the rating methods of evaluation criteria, this study conducted vibration test for both of standard heavy impact sources and actual impact sources. Using the test results, the floor impact sound insulation performance levels were assessed by each of several criteria. In addition, low frequency noise beyond current criteria was evaluated. Consequently, the floor impact sound levels have different performance levels according to adopted criteria, and measured floor impact sounds are bound to annoy the neighbors in the low frequency range. Current criteria does not consider the spectrum characteristics of floor impact sound according to impact sources and low frequency noise. This may cause the difference between the floor impact sound insulation performance level and human perception. Thus current criterion needs to be complemented to reflect the spectrum characteristics of floor impact sound levels according to impact sources and sound pressure levels in low frequency range.