• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 춘계학술논문 발표대회
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• pp.147-150
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• 2007

As recent buildings often use low-quality concrete materials, are constructed defectively, and are put in extreme environmental conditions, many of them show the shortening of life resulting from the corrosion of reinforcing rods by salt damage, carbonization, freezing and thawing, cracking. This in turn raises the cost of repair and maintenance, so it is required to extend the life of structures through enhancing the durability of concrete. In response to the demand, researches on high-durability concrete are being made actively focused on the maximum water-cement ratio, the maximum unit quantity, the minimum cover thickness, the addition of mineral admixtures, etc. With this background, the present study examined the basic physical properties of concrete containing admixtures for enhancing the durability of concrete.

• 자원ㆍ환경경제연구
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• 제16권1호
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• pp.99-127
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• 2007

시간대별 차등요금제(Time-based Pricing)를 포함하여 전력시장에 존재하는 다양한 수요반응(Demand Response) 제도를 개발하고 이를 활성화하기 위한 정책적 수단들이 해외 선진국 전력시장을 중심으로 활발하게 진행되고 있다. 미국의 경우, 2005년 발효된 에너지법에 의하여 이러한 수요반응의 활성화가 준비되고 있으며, 이에 따라 미국의 각 주에서는 신뢰할 수 있고 활용 가능한 수요반응 서비스를 소비자에게 제공하기 위한 다각적인 노력을 시행하고 있다. 즉, 실시간 요금제도(Real-Time Pricing)와 지역별 요금제도(Locational Pricing)의 도입을 통해 시간과 공간에 따른 차등 요금제를 채택하고 있으며, 다양한 인센티브기반 수요반응(Incentive-based DR) 프로그램에 기초하여 기존의 공급자 위주의 수요관리 프로그램들이 시장 친화적 프로그램인 수요반응 프로그램으로 빠르게 변화하고 있다. 우리나라 전력시장에서도 1970년대 이후로 현재까지 다양한 수요관리사업들이 시행되어 오고 있으나, 해외 전력시장의 사례와 같이, 소비자 중심적이고 시장 친화적인 수요자원 활용으로의 전환이 체계적으로 이루어지지 않고 있는 실정이다. 따라서 본 논문에서는 수요반응자원을 전력시장에 도입했을 때 발생할 수 있는 다양한 이익(전력시장 효율 증진 효과, 공급비용 회피 효과, 현물시장 가격감소 효과 등)에 대한 정량적이고 이론적인 분석을 수행하였으며, 이를 통해 수요반응제도 도입의 사회경제적 이익을 계량화하기 위한 방법을 제시하였다.

• 경제분석
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• 제25권3호
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• pp.30-69
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• 2019

본 연구는 국제무역에 참여하고 있는 우리나라의 기업들을 대상으로 수출입이 기업의 노동수요에 미치는 영향을 살펴보았다. 통계청의 기업활동조사 데이터를 이용하여 2006년부터 2014년까지 제조업 24개 업종에 속해 있는 기업들의 수출입이 노동수요에 미치는 영향을 시스템 GMM 방법을 사용하여 분석하였다. 분석 결과, 생산성이 높은 기업에서는 수출이 늘어나면서 생산 확대를 위한 노동수요가 창출되는 효과가 나타난 반면 생산성이 낮은 기업에서는 이러한 효과가 유의하게 나타나지 않았다. 그러나 기업이 오프쇼어링을 이용하여 국내업무를 해외로 재배치한 경우, 수출이 유발하는 노동수요 증가 효과가 축소되는 것으로 분석되었다. 한편, 수입증대는 기업의 노동수요를 감소시키는 것으로 나타나는 데, 이는 수입제품이 노동을 대체하는 효과 때문인 것으로 보인다. 반면 기업이 오프쇼어링을 이용하는 경우, 생산 효율성 증대로 수입의 노동수요 감소효과가 완화되는 것으로 나타났다. 본 연구의 결과는 수출입이 기업의 고용에 미치는 영향은 기업의 생산성 및 글로벌 아웃소싱 참여 여부에 따라 달라질 수 있음을 시사한다.

• 한국유기농업학회지
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• 제25권1호
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• pp.37-52
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• 2017

Three varieties of green pepper - Chungyang pepper, Cucumber-taste pepper and Nokgwang pepper - are competing with one another in consumption due to the overlapping shipment period. The objective of this study is to analyze the influence of monthly variations of shipment quantities on the wholesale market prices. A Linear Approximated Inverse Almost Ideal Demand System (LA/IAIDS) is employed with monthly data set of three different varieties of green pepper consumption. The results show that if there is an excess supply in the market, the rate of the price decline is larger for forcing culture Chungyang pepper than other pepper varieties. On the contrary, change in supply of cucumber-taste pepper and Nokgwang pepper has little effect on the price of Chungyang pepper. The results of this study can be utilized as a basic information for enhancing the farm income and promoting agricultural policies related to the establishment of self-help funds by Chungyang pepper producer groups in Gyeongnam region.

• International Journal of Railway
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• 제5권4호
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• pp.144-147
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• 2012

New transport technologies have been rapidly developed and various transport systems are ready to introduce. However, there no exists effective decision making tools for pre-feasibility studies on transport systems. The pre-feasibility studies should provide reliable solutions about whether a certain transport system is feasible or not by cost-benefit analysis and effectiveness test of enhancing regional economy. This study introduces the smart transport investment/information system (SMARTIS) for supporting decision making with ease, fast and reliable methods. The SMARTIS incorporates travel demand estimates into the process of feasibility studies with automatic data processing methods to give reliable solutions quickly. The SMARTIS is expected to be informative for transit agencies, planners, and operators.

• Smart Structures and Systems
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• 제33권1호
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• pp.27-39
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• 2024

The effectiveness of conventional tuned liquid dampers (TLDs) in controlling the wind-induced response of tall flexible structures has been indicated. However, the impaired control effect in the detuning condition or a considerably high mass cost of liquid may be incurred in ensuring the high-level serviceability. To provide an efficient TLD-based solution for wind-induced vibration control, this study proposes a serviceability-oriented optimal design method for isolated TLDs (ILDs) and derives analytical design formulae. The ILD is implemented by mounting the TLD on the linear isolators. Stochastic response analysis is performed for the ILD-equipped structure subjected to stochastic wind and white noise, and the results are considered to derive the closed-form responses. Correspondingly, an extensive parametric analysis is conducted to clarify a serviceability-oriented optimal design framework by incorporating the comfort demand. The obtained results show that the high-level serviceability demand can be satisfied by the ILD based on the proposed optimal design framework. Analytical design formulae can be preliminarily adopted to ensure the target serviceability demand while enhancing the structural displacement performance to increase the safety level. Compared with conventional TLD systems, the ILD exhibits higher effectiveness and a larger frequency bandwidth for wind-induced vibration control at a small mass ratio.

• 인터넷정보학회논문지
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• 제13권1호
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• pp.117-124
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• 2012

정보서비스는 개방형 혁신, 참여자 중심, Web 2.0 등으로 인해 변화하고 있으며, 정보 수요 분석을 통한 서비스 전략 연구의 중요성은 더 강조되고 있다. 정보 수요를 어떻게 파악하고 분류하는가와 정보서비스 개선 관점에서 어떻게 활용가능한지는 정보서비스 개선 연구에서 중요한 이슈이다. 본 연구에서는 녹색기술 정보이용자를 대상으로 수요 분석 결과를 제시하고, 이를 바탕으로 서비스 개선 방안을 제시한다. 정보유형, 부가기능, 오픈이노베이션 니즈에 대해 소속기관, 담당업무, 종사분야와의 상관관계를 각각 분석한 결과, 종사분야와 세 개의 니즈가 약한 양의 상관관계에 있음을 확인하였으며, 녹색기술 정보서비스에 있어서 종사분야별로 서비스 전략을 차별화하는 것이 유의미함을 밝혔다. 각 정보/기능 니즈와 교차분석을 통해 종사분야별 니즈에 맞는 서비스 전략을 제시한 것은 녹색기술 정보서비스 방향을 점검하는 데 있어 본 연구가 기여한 바이다.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.408-417
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• 2022

Although traditionally perceived as being a visualization and asset management resource, the relatively rapid rate of improvement of computing power, coupled with the proliferation of cloud and edge computing and the IoT has seen the expanded functionality of modern Digital Twins (DTs). These technologies, when applied to buildings, are now providing users with the ability to analyse and predict their energy consumption, implement building controls and identify faults quickly and efficiently, while preserving acceptable comfort and well-being levels. Furthermore, when these building DTs are linked together to form a community DT, entirely new and novel energy management techniques, such as demand side management, demand response, flexibility and local energy markets can be unlocked and analysed in detail, creating circularity in the economy and making ordinary building occupants active participants in the energy market. Through the EU Horizon 2020 funded TwinERGY project, three different levels of DT (consumer - building - community) are being created to support the creation of local energy markets while optimising building performance for real-time occupant preferences and requirements for their building and community. The aim of this research work is to demonstrate the development of this new, interrelated, multi-level DT that can be used as a decision-making tool, helping to determine optimal scenarios simultaneously at consumer, building and community level, while enhancing and successfully supporting the community's management plan implementation.

• International Journal of Computer Science & Network Security
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• 제23권12호
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• pp.13-26
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• 2023

Recently, the development of wireless network technologies has been advancing in several directions: increasing data transmission speed, enhancing user mobility, expanding the range of services offered, improving the utilization of the radio frequency spectrum, and enhancing the intelligence of network and subscriber equipment. In this research, a series of contradictions has emerged in the field of wireless network technologies, with the most acute being the contradiction between the growing demand for wireless communication services (on operational frequencies) and natural limitations of frequency resources, in addition to the contradiction between the expansions of the spectrum of services offered by wireless networks, increased quality requirements, and the use of traditional (outdated) management technologies. One effective method for resolving these contradictions is the application of artificial intelligence elements in wireless telecommunication systems. Thus, the development of technologies for building intelligent (cognitive) radio and cognitive wireless networks is a technological imperative of our time. The functions of artificial intelligence in prospective wireless systems and networks can be implemented in various ways. One of the modern approaches to implementing artificial intelligence functions in cognitive wireless network systems is the application of fuzzy logic and fuzzy processors. In this regard, the work focused on exploring the application of fuzzy logic in prospective cognitive wireless systems is considered relevant.

• 융합경영연구
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• 제11권3호
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• pp.37-46
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• 2023

Purpose: The purpose of this study is to analyze the elderly friendliness of the serious game for dementia prevention and to seek out the influence factors for enhance the friendliness. Research design, data and methodology: It measured the elderly friendliness of the serious game for dementia prevention, run with multi-touchscreens, for 300 elderly people using the Seoul-based General Social welfare centers located at Seoul, and participants evaluated the elder-friendliness of the serious game, by responding to a questionnaire survey. In addition, it analyzed the influence relationship between the elderly friendliness (EF) and the influence factors of the serious game, by setting the factors as the game level (GL), the demand of expectations for demand (DoE) and the prevention & usefulness of cognitive decline (PUCD). Results: the findings show that most of participants positively evaluated the EF of the serious game, regardless of their socio-demographic characteristics. Moreover, it can be found that the more the 'GL DoE and PUCD', the more the 'EF'. The EF was most strongly affected by DoE, followed by PUCD, and then GL Developing and running the serious game by actively reflecting such factors may be one of ways for enhancing the participation in the serious game for dementia prevention and facilitating the sustainable use of it.