• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1029-1033
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• 2004

Concern over the negative environmental impacts associated with the production, use and End-of-Life(EoL) of cellular phones is particularly high due to large production volumes and characteristically short time scales of technological and stylistic obsolescence. Therefore we have to research the environment-friendly technologies and the recycling methods. This paper introduces an improvement of cellular phone remanufacturing processes and develops the Directive of DFE(Design for Environment) for the remanufacturing of a cellular phone. Then We discuss the results of the comparative evaluations.

• Journal of environmental and Sanitary engineering
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• v.15 no.2
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• pp.85-94
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• 2000

The comparative evaluation is the most effective method for site selection because the selection of waste treatment facility is to determine the optimum site out of limited candidate sites. This study adopted the ordinal scale evaluation, one of methods of comparative evaluation. The ordinal scale evaluation aims to determine the investigating items referring to the character of sites, to determine the importance factors for investigating items, and to determine the optimum site according to the quantitative evaluation. This study has focussed on reflecting the opinion of residents to the maximum extent with a weight on social and economic aspects, considering the state of confrontation against each other between the autonomous government organization and local residents, which is being emerged as a social issue relating to the evaluation rating on each item of site selection of an optimum site. Therefore, rational, and clear validity investigations and proper reduction of both time and expenses in site selection as well through this a study.

• Earthquakes and Structures
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• v.10 no.3
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• pp.613-628
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• 2016

The effectiveness of the use of modern repair schemes for the seismic retrofit of existing RC structures were assessed on a comparative experimental study of carbon fiber-reinforced polymer (CFRP) strips and sheets for the repair of reinforced concrete members of RC frames, damaged because of cyclic loading. Two virgin, single - story, one - bay, 1/3 - scale frame specimens were tested under cyclic horizontal loading, up to a drift level of 4%. Then, virgin specimens, B and F, respectively, were repaired and retested in the same way. One, specimen RB, was repaired with epoxy injections and CFRP strips and one, specimen RF, was repaired with epoxy injections and CFRP sheets. The two specimens are used to examine the differences between the structural behavior of frames repaired using CFRP strips and frames repaired using CFRP sheets. Both qualitative and quantitative conclusions, based on the observed maximum loads, loading and reloading stiffness, hysteretic energy absorption and failure mechanisms are presented and compared. The repaired frames recovered their strength, stiffness and energy dissipated reasonably. The use of CFRP sheets was found more effective than CFRP strips, due to the proper anchorage.

• Korean Journal of Plant Taxonomy
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• v.49 no.2
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• pp.107-117
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• 2019

Viburnum in Korea includes ten species. The phylogenetic relationships and morphology of the genus Viburnum in general have been studied substantially for the past three decades. A clear understanding of the systematic relationships and an assessment of the level of morphological variation of these plants distributed in Korea are lacking. This study investigated the morphology of these species using herbarium specimens and fresh materials obtained during fieldwork to examine the morphological variation level for a better understanding of each species in the genus. A comparative analysis showed that the species of Viburnum in Korea are easily distinguishable based on various characters of the bud, leaf, extrafloral nectary, inflorescence, corolla, fruit, and stone.

• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.1
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• pp.19-32
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• 2011

The risk assessment is essential for tunnel design in order to minimize risks associated with uncertainty about geological conditions and tunneling method. This paper provides a comparative risk analysis of a large single bore TBM driven tunnel against sequentially excavated NATM tunnel for a mixed-face large-diameter urban tunnel project near or under a river. The focus of this assessment is on the risks associated with the tunnel excavation methods, in particular whether a TBM or NATM presents more or less risk to achieve the planned excavation duration and bring the project within the estimated bid price. First, the impacts and risks to tunnel construction under each method were discussed, and the risks were scored and ranked in the order of perceived severity and likelihood. Finally, the assessment from a risk based perspective was conducted to decide which alternate tunneling method is more likely to deliver the project with the least time and cost. It is very important to note that this study is only applied to this tunnel project with specific geological conditions and other contract requirements.

• Fire Science and Engineering
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• v.14 no.3
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• pp.27-32
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• 2000

The assessment of wildland fire hazard is the first priority to be considered in the prevention, extinction and control of wildland fire. For the standard to measure wildland fire hazard, the wildland fire Warning System is currently being used in Korea which computes the wildland fire occurrence hazard index through a stick weight to moisture conversion formula. It shows the risk of fuel substance being exposed to fire by meteorological factors. For a comprehensive assessment of wildland fire hazards by area, the major factors'hazards need to be measured and the assessment of wildland fire needs to be conducted through historical statistic examination. Therefore, the wildland (ire outbreak frequency and its seriousness of damage are analyzed through historical statistic examination to conduct the assessment of a wildland fire hazard, and then the calorific value of a forest is analyzed through differential scanning calorimeter measurement which assesses the comparative calorific hazard according to the geographical distribution of vegetation.

• International Journal of Concrete Structures and Materials
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• v.11 no.2
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• pp.199-213
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• 2017

Chloride penetration is among the main causes of corrosion initiation in reinforced concrete (RC) structures producing premature degradations. Weather and exposure conditions directly affect chloride ingress mechanisms and therefore the operational service life and safety of RC structures. Consequently, comprehensive chloride ingress models are useful tools to estimate corrosion initiation risks and minimize maintenance costs for RC structures placed under chloride-contaminated environments. This paper first presents a coupled thermo-hydro-chemical model for predicting chloride penetration into concrete that accounts for realistic weather conditions. This complete numerical model takes into account multiple factors affecting chloride ingress such as diffusion, convection, chloride binding, ionic interaction, and concrete aging. Since the complete model could be computationally expensive for long-term assessment, this study also proposes model simplifications in order to reduce the computational cost. Long-term chloride assessments of complete and reduced models are compared for three locations in France (Brest, Strasbourg and Nice) characterized by different weather and exposure conditions (tidal zone, de-icing salts and salt spray). The comparative study indicates that the reduced model is computationally efficient and accurate for long-term chloride ingress modeling in comparison to the complete one. Given that long-term assessment requires larger climate databases, this research also studies how climate models may affect chloride ingress assessment. The results indicate that the selection of climate models as well as the considered training periods introduce significant errors for mid- and long- term chloride ingress assessment.

• Industry Promotion Research
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• v.8 no.3
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• pp.201-210
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• 2023

This study is based on data ecology theory and takes Chinese local governments' open public data as the research object. Data asset value assessment methods are compared from a new perspective of data business operations. The results show that the assessment model constructed using the hierarchical analysis method (AHP) can more objectively reflect the commercial value of government open data assets than the traditional cost, revenue and market methods, has the advantage of a comprehensive assessment of data value index, and better reflects the findings of a comprehensive index of regional data value. The data show that the local government data value assessment index is positively proportional to the region's digital economy development index, highlighting the driving effect on the digital economy. The results of the study provide a good help for the identification of local government data value rights. The research and practice of promoting the construction of data innovation and data business operation models, improving social well-being and promoting the rapid development of the digital economy to achieve data realisation provides a good reference.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2A
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• pp.293-300
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• 2006

There is a high degree of uncertainty in measurements of the thickness or the loss of thickness of corroded elements. Generally the thickness of corroded elements varies from one location of the element to another depending on the degree of corrosion, which makes the safety assessment difficult. Therefore, a procedure for safety assessment of corrosion- damaged steel structures using an imprecise reliability is proposed in this paper. The proposed safety assessment procedure using the imprecise reliability was also applied to a cable-stayed bridge in Korea to demonstrate its effectiveness and applicability. Since there is a large variation in measurements of the thickness of corroded elements, the thickness of corroded elements was considered as the imprecise element. This variation was found to be directly related to the degree of corrosion. Therefore, the variation increases as the degree of corrosion increases. Based on the comparative observations between the conventional reliability and the imprecise reliability, it is suggested that the imprecise reliability analysis derived based on the subjective or statistical judgment of conditional independence could be successfully utilized for the risk or safety assessment of corrosion-damaged structures.

• Journal of Environmental Impact Assessment
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• v.20 no.6
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• pp.823-831
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• 2011

파라과이와 한국의 환경영향평가에 관련된 제도와 법률은 환경영향평가 대상사업, 실행방법 및 사후감시 등에서 상이하다. 양국의 환경영향평가 제도 중에는 전혀 관련 없는 것도 있는데, 경제적, 사회적, 문화적, 역사적 그리고 지연조건이 상이하여 양국의 환경영향평가 제도에 영향을 주는 것으로 분석된다. 파라과이에서는 스코핑이 Term of References (TOR)가 준비되는 단계이다. TOR은 환경부에 의해 준비된 특정의 환경영향평가의 요구조건을 포함한다. 파라과이에서는 스코핑 단계에서 환경부의 주도로 주민참여가 진행된다. Environmental Impact Relatorio (RIMA)가 개발사업으로 인해 영향을 받는 지역사회에 시행되고, 간결하고 이해하기 쉬운 표현으로 작성된다. 파라과이에서는 EIS가 승인되기 전에 RIMA를 지역사회에 공개한다.