• 문화기술의 융합
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• 제8권4호
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• pp.127-134
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• 2022

최근까지 많은 학자 및 기업에서 장기간의 고객유지 및 지속적인 수익성 등을 달성하기 위해서 고객 충성도를 제고하기 위한 노력을 쏟아 왔다. 본 논문에서는 고객 충성도를 태도적 및 행동적 차원으로 구분해서 이에 영향을 미치는 선행변수들을 고찰해 볼 수 있는 연구모형을 구상하였다. 구체적으로 자아일치성과 고객 충성도 사이에서 지각된 가치가 매개역할을 수행하는지도 살펴 보았다. 연구결과 자아일치성은 직접적이고도 긍정적인 영향력을 지각된 가치와 고객 충성도에 미치고 있었다. 또한 자아일치성이 태도적 및 행동적 충성도에 영향력을 미치는 상황에서, 지각된 가치가 매개역할을 수행하고 있음을 확인할 수 있었다. 본 연구결과를 이용해 현장의 담당자들과 관련 산업에 하나의 판단근거를 제시할 수 있었다.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.984-991
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• 2022

The use of the sustainability rating systems in infrastructure construction projects is not as common in comparison to building construction projects. While the sustainability rating systems share some commonalities, they differ from one another in certain ways. Thus, project teams cannot make reliable decisions when choosing the best sustainability rating tools for a given infrastructure projects. The Department of Transportation (DOT) in several states are developing its own rating system to address the infrastructure sustainability, but not in the case of California. Therefore, this paper presents the statistical results on the important sustainability determinants that affects the success of meeting sustainability goals of infrastructure construction projects. The authors conducted an online survey using the structured questionnaires. The categories considered include site, water/wastewater, energy, materials/resources, environmental, and others. The statistical analyses such as Kruskal-Wallis and ANOVA are conducted using a total of 25 valid and complete data out of 59 surveys collected. The results demonstrate several factors under each of six major sustainable categories have received higher ranks than other factors. The results also show that a statistically significant difference can be found from water, energy, and environmental categories against the other category based on the pairwise comparisons.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.543-550
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• 2022

The U.S. Department of Energy conducts the Solar Decathlon competition as a student-based achievement that encourages sustainable design with energy efficiency and solar energy technologies. In the 2020 competition, the University of Nevada, Las Vegas (UNLV) team designed, fabricated, and constructed a net-zero modular house that applies innovative and highly efficient building technologies. This paper focused on the lessons learned during the early phases of this ongoing modular project. The research methodology included obtaining feedback from key project participants using a well-structured questionnaire. The results showed that the major items/challenges in the project's planning phase included selecting the modular size, planning the construction system, planning the materials and procurement, estimating costs and duration, selecting a fabricator, collaboration and communication, safety, and planning module transportation. These findings will help modular practitioners and future Solar Decathlon competition participants better understand how and what factors they should consider most during the early phases through the lessons learned.

• 신재생에너지
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• 제19권1호
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• pp.12-21
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• 2023

Governments and global companies are working towards using renewable sources of energy, such as solar, wind, and biomass, to reduce dependency on fossil fuels. In the defense sector, the new strategy seeks to increase the sustainable use of renewable energy sources to improve energy security and reduce military transportation. Renewable energy technologies are affected by factors such as climate, resources, and policy environments. Therefore, governments and global companies need to carefully select the optimal renewable energy sources and deployment strategies. Biomass is a promising energy source owing to its high energy density and ease of collection and harvesting. Many techniques have been developed to convert the biomass into electrical energy. Recently, diverse types of fuel cells have been suggested that can directly convert the chemical energy of biomass into electrical energy. The recently developed biomass flow fuel cell has significantly enhanced the power density several hundred times, reaching to ~100 mW/cm². In this review, we explore various strategies for producing electrical energy from biomass using modern methods, and discuss the challenges and potential prospects of this method.

• 유통과학연구
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• 제22권1호
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• pp.25-36
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• 2024

Purpose: The study attempts to explore the operational performance of the existing Malaysian logistics companies and the extent of their adoption of digitalization. The role of digitalization in enhancing the performance of companies in the logistics industry in Malaysia, for value creation, is the topic of study. Research design, data and methodology: A qualitative research method with a semi-structured interview approach was applied and judgmental sampling was used as the sampling technique to collect data. The research has chosen nine companies in the logistics industry in Peninsular Malaysia, with the interviews aimed at eleven members of top and middle-level management. Data analysis was performed using logical system techniques to examine and evaluate data, reorganizing feedback, comparing it with literature, and transforming it into structured, valuable information after interviews. Results: The study revealed mixed opinions on digitalization in logistics, despite its potential benefits such as improved operational efficiency, real-time information, and customer service. However, high costs may hinder financial performance and require revisions due to stakeholder involvement. Conclusions: The Malaysian logistics industry's adoption of digitalization is gaining traction, with most companies satisfied with their status. However, challenges like cost and inefficiency persist, prompting calls for government support to improve efficiency and reduce costs while ensuring sustainable transportation.

• 한국포장학회지
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• 제29권3호
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• pp.181-193
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• 2023

In this study, we conducted a comparative life cycle assessment (LCA) of two different products, considering reusable and single-use packaging for fresh food distribution. For reusable packaging, we utilized expanded polyethylene (EPE), while for comparison, a disposable box made of widely used expanded polystyrene (EPS) was selected. We comprehensively analyzed the environmental impacts of production, transportation, reprocessing (for reused boxes), and disposal across 18 impact categories. Upon analyzing the actual reuse of 300 rounds of fresh food, the cumulative global warming potential (GWP) values for the EPE box were found to be 280.21 kg carbon dioxide (CO₂) eq, demonstrating a significant 75% reduction compared to those of the EPS box. Furthermore, it was observed that the GWP values for the EPE boxes became equivalent to those of the EPS boxes after 12 rounds of reuse. In conclusion, reusable packaging shows substantial potential to contribute to the reduction of environmental burdens, aligning well with global environmental requirements for sustainable food distribution and related industries.

• Tribology and Lubricants
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• 제40권3호
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• pp.71-77
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• 2024

Hydrogen has emerged as an eco-friendly and sustainable alternative to fossil fuels. However, the utilization of hydrogen requires high-pressure compression, storage, and transportation, which poses challenges to the durability of compressor components, particularly the diaphragm. This study aims to improve the durability of 304 stainless steel diaphragms in hydrogen compressors by optimizing their surface roughness and corrosion resistance through wet etching. The specimens were prepared by immersing 304 stainless steel in a mixture of sulfuric acid and hydrogen peroxide, followed by etching in hydrochloric acid for various durations. The surface morphology, roughness, and wettability of the etched specimens were characterized using optical microscopy, surface profilometry, and water contact angle measurements. The friction and wear characteristics were evaluated using reciprocating sliding tests. The results showed that increasing the etching time led to the development of micro/nanostructures on the surface, thereby increasing surface roughness and hydrophilicity. The friction coefficient initially decreased with increasing surface roughness owing to the reduced contact area but increased during long-term wear owing to the destruction and delamination of surface protrusions. HCl-30M exhibited the lowest average friction coefficient and a balance between the surface roughness and oxide film formation, resulting in improved wear resistance. These findings highlight the importance of controlling the surface roughness and oxide film formation through etching optimization to obtain a uniform and wear-resistant surface for the enhanced durability of 304 stainless steel diaphragms in hydrogen compressors.

• 한국환경보건학회지
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• 제50권2호
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• pp.81-82
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• 2024

Urban air mobility (UAM) is emerging as an innovative transportation solution for cities. However, the potential noise impact on urban life must be carefully examined. Continuous exposure to UAM noise, with its unique frequency characteristics and temporal variability, may adversely affect citizens' health by causing sleep disorders, cardiovascular disease, and cognitive impairmenet, particularly in children. NASA has formed a UAM Noise Working Group to study this issue comprehensively. In Korea, the Seoul Metropolitan Government's UAM demonstration project is expected to accelerate related research and development. Scientific analysis, including noise measurement, prediction modeling, and health impact assessment, must be prioritized. Measures to minimize noise should be established based on this evidence, such as optimizing flight modes, developing noise reduction technologies, and establishing new noise management standards. Transparency and social consensus are crucial throughout this process. Expert review and open communication with civil society are necessary to address related concerns. Sharing demonstration project results and providing opportunities to experience UAM noise through digital twin simulations can help address public concerns and build social consensus. Proactively and scientifically tackling noise issues is essential for the sustainable development and successful integration of UAM into daily life.

• 한국철도학회논문집
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• 제17권1호
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• pp.59-69
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• 2014

국가 전체의 지속가능한 교통체계 확립을 위한 연계교통체계의 구축이 중요한 교통정책으로 대두되고 있고 철도 및 대중교통은 통행의 완결성 부족으로 인해 수단간 연계성을 고려하는 것이 필수적이라 할 수 있다. 특히, 고속철도는 우리나라 교통체계의 획기적 변화를 가져왔고 고속철도역은 다양한 수단이 연계되어야 하는 중요한 교통 결절점으로 수단간 연계교통망 차원에서 분석이 필요하다. 이에 본 연구는 고속철도역의 연계교통망 차원에서 고속철도와 연계교통수단의 연계기능을 객관적이고 정량적으로 분석하기 위한 새로운 연계성 분석 기법을 제시하였다. 서울역, 부산역, 울산역, 신경주역을 공간적 범위로 설정하였고 고속철도 역사내의 내부환승 시설을 제외한 고속철도역과 영향권내 기 종점간을 연결하는 연계교통수단의 세부 연계기능 지표를 조사 분석하였다. 구축된 자료를 이용하여 구조방정식 모형을 적용한 연계성 분석 기법을 제시하고 연계성 지표를 개발하였다.

• 콘크리트학회논문집
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• 제22권6호
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• pp.787-796
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• 2010

전 세계적으로 지구 온난화의 주요원인인 $CO_2$ 발생에 대한 규제가 강화되고 있다. 반 환경산업으로 인식되는 건설 산업의 주요자재로서 다량의 $CO_2$를 배출하는 콘크리트는 생산과정에서 발생된 $CO_2$ 배출량 감소에 대한 필요성이 인식되었다. 이 논문에서는 콘크리트를 기초로 하여 자재생산, 운송, 제조단계에서 발생하는 $CO_2$ 배출량을 평가하기 위한 시스템을 구축하고, $CO_2$ 배출량을 효율적으로 저감하고 평가하기 위한 프로그램을 개발 하였다. 평가결과, 대부분의 $CO_2$ 배출량은 자재생산단계에서 발생했으며, 자재, 운송, 제조단계에서 배출된 $CO_2$ 배출량에 대하여 정량적으로 평가하였다. 더욱이, $CO_2$ 배출량을 저감하기 위하여 각 단계별로 친환경 기술을 적용하여 평가가 가능한 이 평가시스템은 콘크리트 생산에 따른 $CO_2$ 배출량을 정량적으로 평가하기 위한 시스템으로 제안할 수 있으며, 국내 레미콘생산업체는 $CO_2$ 배출량 평가를 하기 위해 이 시스템을 사용할 수 있다.