• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 추계학술대회 논문집
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• pp.276-277
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• 2012

This study was carried out in the laboratory of the reverberation. A total of six specimens were fabricated depending on the thickness and strength. Floor impact sound insulation performance was measured in 1/3 octave band center frequency. The results of this study are as follows. Although some differences in the frequency band, the result of evaluating the weight impact sound blocking performance as the thickness increases, the floor impact sound insulation performance is improved. In addition, to increase the strength of the slab, even if the block impact sound performance is improved.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.182-183
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• 2014

In case of large soft body impact test at the construction site, the test conditions are different from conditions at the laboratory, and the length of rope to hold the impact specimen must be changed. In a previous study, the fact that the size of impact load is varied by the length of rope on the large soft body impact specimen was confirmed. In this study, the length of rope and fall height were set as independent variables to conduct the load analysis test. It was determined that the load fluctuation was occurred depending on the length of rope under the fall height over 100 mm, and it is concluded that the additional setup of fall height to modify the actual impact load size is required when the length of rope is below 2.5 m. In this study, the modified formula to put equal size of impact load regardless of the length of rope was extracted through the experiment.

• Nuclear Engineering and Technology
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• 제54권10호
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• pp.3766-3777
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• 2022

It is essential to ensure the safety of spent nuclear fuel (SNF) transport cask in drop situation that is included in transport accident scenarios. The safety of the drop situation is affected by the impact absorption performance of impact limiters. Therefore, when designing an impact limiter, the uncertainty in the material properties that affect the impact absorption performance must be considered. In this study, the material properties of the wood inside the impact limiter were selected as the variables for a parametric study. The sensitivity analysis of the drop response of the SNF transport cask with impact limiter was performed. The minimum wood strength required to prevent a direct collision between the cask and floor was derived from the analysis results. In addition, the plastic strain response was analyzed and strain-based evaluation was performed. Based on this result, the critical values of wood properties that change the impact dynamic characteristics were investigated. Finally, the optimal material properties of wood were obtained to secure the structural safety of the SNF transport cask. The results of this study can contribute to the development of SNF transport cask, thereby ensuring safety in transport accident conditions.

• 상하수도학회지
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• 제25권6호
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• pp.885-892
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• 2011

In this study, LCA(Life Cycle Assessment) on 'Saemangum CSO Project' was carried out to evaluate environmental impact which occurred during the construction and operation periods and the potential environmental impact reduction was analyzed by comparing production and reduction level of pollution loads. LCA was conducted out according to the procedure of ISO14040 which suggested Goal and Scope Definition, Life Cycle Inventory Analysis, Life Cycle Impact Assessment and Interpretation. In the Goal and Scope Definition, the functional unit was 1 m3 of CSO, the system boundary was construction and operation phases, and the operation period was 20 years. For the data collection and inventory analysis, input energies and materials from civil, architecture, mechanical and electric fields are collected from design sheet but the landscape architecture field is excepted. LCIA(Life Cycle Impact Assessment) was performed following the procedure of Eco-Labelling Type III under 6 categories which were resource depletion, eutrophication, global warming, ozone-layer destruction, and photochemical oxide formation. In the result of LCA, 83.4% of environmental impact occurred in the construction phase and 16.6% in the operation phase. Especially 78% of environmental impact occurred in civil works. The Global warming category showed the highest contribution level in the environmental impact categories. For the analysis on potential environmental impact reduction, the reduction and increased of environmental impact which occurred on construction and operation phases were compared. In the case of considering only the operation phase, the result of the comparison showed that 78% of environmental impact is reduced. On the other hand, when considering both the construction and operation phases, 50% of environmental impact is increase. Therefore, this study showed that eco-friendly material and construction method should be used for reduction of environmental impact during life cycle, and it is strongly necessary to develop technology and skills to reduce environmental impact such as renewable energies.

• 한국소음진동공학회논문집
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• 제23권12호
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• pp.1117-1126
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• 2013

The standard impact sources, standardized to rate the sound insulation performance of floor structure, should simulate well the real floor impact sources, which is very important to grade the floor structure then to establish counter plan to improve the performance of floor. Recently the tire, the standard heavyweight impact source, has been discussed that the impact force is too big to represent the real impact force. And researches have been carried on the applicability as a substitute or a supplementary. In addition, tapping machine, the standard lightweight impact source, is also questionable if it is representative of real lightweight impact source. This study aims to examine the similarity of standard impact sources with living impact sources, comparing the physical characteristics such as impact force, frequency contents and sound level. The result showed that the physical characteristics of standard impact sounds were somewhat different with that of living impact sounds, and the standard sources couldn't be verified from this result. Later subjective evaluation should be followed to compare how the physical differences make relationship with the subjective differences.

• 환경영향평가
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• 제13권2호
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• pp.57-71
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• 2004

This study aims to review the environmental impact assessment systems of Japanese local governments, to compare its outcome with the systems of Korean local governments, and to suggest the development direction for the environmental impact assessment systems of Korean local governments based on the result. The study results showed that, first, due to distinction in the political systems of Japan and Korea, while Japan has bottom-up environmental impact assessment systems, Korea has topdown environment impact assessment systems. Second, although introduction of national systems on planning was put on hold as a future initiative, local governments including Tokyo and Saitama are experimenting evaluation procedures tailored to local features by legislating them as regulations. On the other hand, while 'prior environmental review system' was in effect as a national system, nothing was practiced at all by local governments. Third, in a total of 47 Japanese local governments, about 45 projects and 44 assessment items were added to local government environmental impact assessment only and designated as target projects and assessment items. Fourth, in both national and local environment impact assessment systems in Japan, screening procedures to determine assessment by separating into Type 1 projects and Type 2 projects and scoping procedures to discuss assessment items in advance were introduced and in effect. This Japanese EIA system may serve as a good reference to the Korean national and local government EIA systems.

• 환경영향평가
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• 제21권1호
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• pp.15-24
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• 2012

The purpose of this study is to understand the process and characteristics of social impact caused by development projects through research and analysis on issues presented during development projects carried out in Korea. Furthermore, on the basis this analysis, this study proposes possible improvement measure environmental impact assessment for minimizing social impact of development projects in the future. Issues related to development projects are generated mainly by the following three causes. Initial social impact can occur when a development project directly causes certain changes in natural, living and social environment. Operational problems related to assessment are another cause of social impact, and it can also occur when changes in natural and living environment work in tandem with social environment sphere. Social impact of development projects is not brought about solely by changes in social environment, but is the result of interaction of factors such as changes in social, natural, living environment and problems related to assessment or operation/management. As to why the current environmental impact assessment could not provide satisfactory solution to the issues mentioned above, this study suggests the following reasons: limitations of assessment method used in social environment category, difficulties in defining assessment criteria, limitations inherent in criterion referenced assessment method, insufficient issue-making in local community, and lack of participation on the part of local residents. Possible solutions for these limitations are as follows: 1) To identify local issues in social environment category through participation of local experts in scoping stage, 2) To adopt deliberative method for local participation, 3) To utilize social survey technique.

• International Journal of Computer Science & Network Security
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• 제22권12호
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• pp.19-28
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• 2022

The study aimed to identify the impact of Applications of Internet of things on practice of knowledge management in organizations: the mediating role of employees' Engagement. A quantitative questionnaire survey is conducted. The study population consisted of all senior and middle administrations in small and medium enterprises in Jordan. The study sample consisted of (350) senior and middle administrations. The study sample was selected by random stratified method. The results revealed that There is an impact of Applications of Internet of things on the practice of knowledge management at (α ≤ 0.05) in the small and medium enterprises in Jordan. Furthermore, there is an impact of Applications of Internet of things on the employees' Engagement. The current study provided some important insights into an issue that requires further research. Understanding the applications of the Internet of Things and their impact on improving knowledge management is of paramount importance in raising the quality of products and improving the company's image, as shown in this research.

• 환경영향평가
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• 제21권5호
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• pp.801-811
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• 2012

For biodiversity conservation, Biological Impact Assessment is very important. The focus of the study is to enhance efficient Environment Impact Assessment(EIA) based on collecting existing information of endangered species covering the status survey, estimation of effects and reducing methods. Habitat Suitability Index(HSI) can be applicable to Ecological Impact Assessment and finding various reducing methods based on estimating effects. For this study, the EIA report of Samjang - Sanchung highway construction was chosen as an example and Prionailurus bengalensis euptilura as an endangered species was chosen to assess the ecosystem impact on road construction. Water, road, ground coverage, slope, altitude as variables of habitat were weighted and final HSI map was calculated using Arc map and Arc view. Through comparing of before and after HSI, quantitative estimating on effects was possible to minimize impact of road construction to wildlife habitat.

• 한국IT서비스학회지
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• 제19권5호
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• pp.107-124
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• 2020

Due to spread of covid-19, which began in December 2019, the usage of online distance learning has expanded within colleges. However, because of the lack of readiness for running online distance learning, professors and students had to experience a lot of inconvenience. In the near future, the usage of online distance learnig is expected to more expand, thus, it seems that there should be a strategies for sustainable online learning operations. This study aims to investigate which factors have impact on the continuance intention to usage of online distance learning of airline department students, focused on Post-Acceptance Model. For the empirical analysis, this study utilized a structural equation model after collecting 136 survey data. The results is as follow; First, user interface has positive impact on confirmation and confirmation has positive impact on satisfaction of online distance learning. Seconds, confirmation has positive impact on perceived usefulness, flow and social presence. Third, social presence has positive impact on satisfaction of online distance learning, but perceived usefulness and flow didn't have statistically meaningful impact on satisfaction. Finally, statisfaction of online distance learning has huge positive impact on continuance intention to usage. It is expected that the implications of this study enable colleges effectively to run online distance learning in preparation for the post-covid 19 era.