• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.5 s.98
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• pp.542-549
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• 2005

Impact sounds, such as those created by footsteps, the dropping of an object or the moving of furniture, can be a source of great annoyance In residential buildings. Running and jumping impact sound by child are one of the most irritating noises in an apartment buildings. It's necessary to know that the impact power characteristics of real impact source in an apartment buildings. This study aims to Investigate the impact power characteristics and impact power time of running and jumping by child. This study carried out investigation through the 159 children in school. The results of this study is that jumping impact power is greater than running impact power.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.265-268
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• 2004

Impact sounds, such as those created by footsteps, the dropping of an object or the moving of furniture, can be a source of great annoyance in residential buildings. Running and jumping impact sound by child are one of the most irritating noises in an apartment buildings. It's necessary to know that the impact force characteristics of real impact source in an apartment buildings. This study aims to investigate the impact force characteristics and impact force time of running and jumping by child. This study cud out investigation through the 155 children in school. The results of this study is that jumping impact force is greater than running impact force but impact force time is lower than that.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.865-868
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• 2002

This study investigated the shape deformation of ball projectile(5.56mn) under the low energy impact by the use of the drop weight impact tester. ball projectile(5.56mm) consisted of the copper face with a lead core. The impact conditions were changed with the variations of the mass and the drop height of the impact tup. Shape deformation of ball projectile(5.56mm) after low velocity impact was measured using a video microscope and CCD camera. The test result showed that impact energy by changing of drop height of the impact tup affected shape deformation of ball projectile(5.56mm). So, it is important to study the relativity between shape deformation of ball projectile(5.56mm) and ballistic protection of plate(such as hybrid composite laminates) under the high velocity impact.

• Journal of Environmental Impact Assessment
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• v.16 no.1
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• pp.45-58
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• 2007

Despite the ubiquitous practice of environmental impact assessment around the world, social impact assessment has been alienated from assessment process from the beginning. Not until 1993 was 'Interorganizational Committee' established in the United States to prepare for 'Principles and Guidelines for Social Impact Assessment.' This study is an attempt to critically examine US 'Principles and Guidelines.' First, the study traces history of social impact assessment to reveal why the latter became "the orphan in the assessment process." Second, it critically reviews 'Principles and Guidelines' to find its merits and defects. For instance, a principle regarding environmental justice is perceived as necessary as society has become conscious of social justice and equity while putting too much emphasis on predictive traits of social impact assessments only fosters "checklist mentality." Third, the study reflects on 'Principles and Guidelines' in particular and social impact assessment in general in order to probe what is social impact assessment. To do so, it pays attention to scholars, who have criticized technocratic and procedural elements of 'Principles and Guidelines.' They show that social impact assessment is philosophically and methodologically teleological in that "fluid and contested meanings" between social impacts and the public are meaningful in itself. And simple procedural guarantee of the public involvement, they argue, is not enough to define social impacts. Lastly, from the critical analysis of 'Principles and Guideline,' the study looks for alternatives to improve how to assess social impacts in a Korean context.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.545-548
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• 2008

In this study, the concept of safety impact assessment to achieve 'Design-for-Safety' in design phase is introduced. For this purpose, safety impact assessment model was devised and a methodology using the risk-based safety impact assessment approach for NATM of tunnel projects is suggested. The suggested methodology includes safety information survey, classification of safety impact factors caused by design and construction, and quantitative estimation of magnitude and frequency of safety impact factors. A real-world case study on the safety impact assessment of a tunnel construction project is also provided in the paper.

• Journal of KSNVE
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• v.7 no.4
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• pp.669-679
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• 1997

This paper deals with a study of striker type impact hammer drill for improving the drilling performance. The study was performed through a numerical simulation of the impact hammer mechanism and an experimental comparison of the numerical simulation results was followed. Optimization of the impact mechanism was also performed. The numerical model of the impact hammer drill takes into account the striker motion and the effects of the pressure in the cylinder as well as the friction acting on the striker. The equation of motion is solved with the pressure equation in the cylinder including the friction force. The friction is considered as a combination of Coulomb friction and viscous damping friction. At the moment of impact, an ideal impact model that uses restitution coefficient is used to calculate the sudden change of the striker motion. The numerically simulated impact force shows a good agreement with the experimental result and thus, the validity of the numerical model is proven. Based upon the proposed model, an optimization was performed to improve the impact force of the hammer drill. The objective function is to maximize the impact force and the used design variables are striker mass, frequency of piston, bit guide mass, cylindrical diameter and dimensions of the mechanism components. Each design variable and some other conditions that are essential to manitain normal operation of the hammer drill are considered as constraints. The optimized result show a remarkable improvement in impact force and an experimental proof was investigated.

• Journal of Environmental Impact Assessment
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• v.14 no.4
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• pp.217-225
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• 2005

In apartment buildings, floor-impact sound has bean regarded as the major source which induces complaints from residents. It is mainly due to the use of light-weight structures. The vibration produced by impact on one part of an apartment building would travel as far as the other parts of structure with a little alleviation. As a result, the impact sound from upstairs has been regarded as a main source of noise causing discontentment among occupants. This study was carried out to measure the floor-impact sound levels and evaluate the insulation performance of floor-impact sound for nine apartment buildings. The floor-impact sound levels were measured for twenty-five On-dol floor structures and various factors which influence the floor-impact sound were analyzed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.8 no.1
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• pp.64-70
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• 2009

This study is to analyze the impact of automotive body with computer simulation. The total deformation, equivalent strain and strain and principal stress are analyzed respectively in case of front, rear and side impacts. The maximum total deformation of side impact is more than 6 times as large as that of rear impact. The maximum equivalent strain or stress of side impact is more than 4 times as large as that of rear impact. These deformation, strain and stress of front impact are a little more than those of rear impact. The maximum principal stress of side impact is more than 4.5 times as large as that of rear impact. This stress of front impact is a little more than that of rear impact.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.419-422
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• 2014

Floor impact sound level is affected by various factors. This study was examined about impact sources and floor coverings influenced at floor impact sound. So this study wishes to get method to reduce sound pressure level of receiving room. Light-weight impact sound in mid frequency and Heavy-weight impact sound in low frequency was affected by floor coverings. Therefore, method to reduce floor impact sound level is to use proper floor coverings. Some coverings can amplify the heavy-weight impact sound in low frequency. Floor impact sound sources used measurement and analysis were standard heavy-impact source(Tapping, Bang, Ball) and living impact sources(Cleaner, Chair, Toy-car, Soccer ball). And Floor coverings used measurements were various thickness vinyl, laminate(or ply-wood) floor. Especially vinyl floor coverings were very effective method to reduce floor impact.

• Journal of the Korean Home Economics Association
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• v.50 no.7
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• pp.97-107
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• 2012

The aim of this study is to suggest the introduction of family impact analysis. Family impact analysis is needed to evaluate family policies from the family perspective. This study deals with the definition of family impact analysis and the cases of other impact analysis, such as gender impact assessment and employment impact analysis. In addition, this study suggests the introduction of family impact analysis with evaluation methods, evaluation indicators, and evaluation processes. Evaluation methods are divided into self-assessment and specific-assessment. Evaluation indicators need to be developed based on the family strength. This research also suggests the securing of family time as a basic assessment indicator. The evaluation processes consist of object selection, assessment, evaluation report, and policy improvement. Finally, this study suggests that family impact analysis is a strong strategy for promoting family-friendly policies. In order to introduce family impact analysis in a more systematic manner, further studies on the standards of assessment, formation of research institutions, and the legislative system will be necessary.