• 한국지반신소재학회논문집
• /
• 제9권4호
• /
• pp.75-84
• /
• 2010

본 연구에서는 띠형 섬유보강재의 인장특성, 크리프 변형, 내시공성 및 내구성을 평가하기 위한 일련의 장기성능 평가시험을 수행하였다. 또한 시험결과를 바탕으로 장기설계인장강도 산정을 위한 강도감소계수를 평가하였다. 먼저, 크리프 변형 특성을 평가하기 위해 단계 등온법과 시간-온도 중첩법을 이용하였으며, 크리프 감소계수는 1.6을 적용하는 것이 바람직한 것으로 평가되었다. 다음으로 입도 조정된 화강풍화토를 성토재로 사용하여 수행한 내시공성 시험 결과, 보강재의 강도특성에 영향을 미치는 원사의 손상이 거의 없는 것으로 확인되어, 장기설계인장강도에 큰 영향을 미치지 않을 것으로 분석되었다. 마지막으로 내구성 평가 결과, 내화학성, 내미생물 및 내후성을 고려한 강도감소계수는 1.1을 적용하는 것이 합리적인 것으로 평가되었다.

• 한국컴퓨터정보학회논문지
• /
• 제19권2호
• /
• pp.221-231
• /
• 2014

본 연구는 전략적 제휴와 연계를 추구하는 장기 지속적인 그린IT 전략의 필요성을 제시하였다. 그린IT 기업의 사회적 압력과 환경지향성과 환경매력도가 장기 지속적 그린IT 전략에 어떠한 영향을 미치는지, 장기 지속적 그린 IT 전략이 환경성과에 어떠한 영향을 미치는가를 알아보기 위한 연구모형을 설정하였다. 선행연구에서 종속변수로 사용되던 장기지속성을 본 논문에서는 매개변수로 설정하였다. 그린IT 기업을 대상으로 설문조사를 실시하였고, 통계패키지를 이용하여 실증적으로 분석하였다. 사회적 압력과 환경지향성과 환경매력도와 환경성과 사이의 관계에서 장기지속성이 매개효과가 있음을 검증하였다.

• 한국도로학회논문집
• /
• 제18권1호
• /
• pp.63-72
• /
• 2016

PURPOSES : The use of roller-compacted concrete pavement (RCCP) is an environmentally friendly method of construction that utilizes the aggregate interlock effect by means of a hydration reaction and roller compacting, demonstrating a superb structural performance with a relatively small unit water content and unit cement content. However, even if an excellent structural performance was secured through a previous study, the verification research on the environmental load and long-term durability was conducted under unsatisfactory conditions. In order to secure longterm durability, the construction of an appropriate internal air-void structure is required. In this study, a method of improving the long-term durability of RCCP will be suggested by analyzing the internal air-void structure and relevant durability of roller-compacted concrete. METHODS : The method of improving the long-term durability involves measurements of the air content, air voids, and air-spacing factor in RCCP that experiences a change in terms of the kind of air-entraining agent and chemical admixture proportions. This test should be conducted on the basis of test criteria such as ASTM C 457, 672, and KS F 2456. RESULTS : Freezing, thawing, and scaling resistance tests of roller compacted concrete without a chemical admixture showed that it was weak. However, as a result of conducting air entraining (AE) with an AE agent, a large amount of air was distributed with a range of 2~3%, and an air void spacing factor ranging from 200 to $300{\mu}m$ (close to $250{\mu}m$) coming from PCA was secured. Accordingly, the freezing and thawing resistance was improved, with a relative dynamic elastic modulus of more than 80%, and the scaling resistance was improved under the appropriate AE agent content rate. CONCLUSIONS : The long-term durability of RCCP has a direct relationship with the air-void spacing factor, and it can be secured only by ensuring the air void spacing factor through air entraining with the inclusion of an AE agent.

• 공업화학
• /
• 제34권1호
• /
• pp.75-79
• /
• 2023

The International Maritime Organization (IMO) Marine Environmental Protection Committee (MEPC) may adopt actions after completing impact assessments and reviewing results in accordance with the original strategy and impact assessment procedure (MEPC.1/Circ.885). The assessment of the impact of greenhouse gas (GHG) reduction measures is an important step in determining whether to implement GHG regulations. This study identifies and proposes improvements in the impact assessment procedure for future mid- and long-term measures. Improvements for future measures should start with a review of "the procedure for assessing impacts on states of candidate measures" and "the actual process of the comprehensive impact assessment for short-term measures in 2021." The procedural improvements were largely derived from the order and period of task performance, the clear definition of terms, and the review of task results through lessons learned, analysis, and expert workshops. The impact assessment of future mid- and long-term measures should be procedurally improved to ensure uniformity and consistency, which will provide objective results for Member States and industries to help smooth the adoption of measures.

• 한국태양에너지학회 논문집
• /
• 제26권3호
• /
• pp.1-8
• /
• 2006

The objective of this research is to study on the analysis of long-term performance characteristics of various solar thermal system for heating protected horticulture system for reducing heating cost, increasing the value of product by environment control, and developing advanced culture technology by deploying solar thermal system. Long term field test for the demonstration was carried out in horticulture complex in Jeju Island. Reliability and economic aspect of the system which was operated complementary with thermal storage and solar hot water generation were analyzed by investigating collector efficiency, operation performance, and control features. Optimum operating condition and its characteristics were closely investigated by changing the control condition based on the temperature difference which is the most important operating parameter. However, it is expected that, in high-insolation areas where large-scale ground storage is adaptable, solar system demonstrated in the research could be economically competitive and promisingly disseminate over various application areas.

• 한국도로학회논문집
• /
• 제7권2호
• /
• pp.77-86
• /
• 2005

국내 고속도로 장기공용성 조사구간의 파손자료와 기후자료 및 포장물성 자료를 이용하여 줄눈 콘크리트 포장의 스폴링 모형이 개발되었다. 줄눈 콘크리트 포장 장기공용성 조사구간 22개소의 스폴링 파손 상태가 1999년과 2004년에 각각 조사되어 총44개의 스폴링 파손 자료가 수집되었으며 각 위치에서의 기후자료 및 포장의 형태 및 물성 자료 또한 수집되었다. 수집된 자료들의 민감도 분석을 통하여 스폴링 발생에 영향이 큰 인자들을 찾아내었으며, 그 인자들을 다중 회귀분석하여 스폴링 파손 모형이 개발되었다. 개발된 스폴링 모형은 외국의 모형과 비교할 때 합리적인 스폴링 발생 추이를 보였다.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
• /
• pp.110.1-110.1
• /
• 2011

This study analyzed the performance of long term operation photovoltaic system The 50 kWp grid connected photovoltaic system which was installed at KEPRI site in 1999 has been operated more than 12 years. In order to acquire long term operation characteristics of medium size photovoltaic system, the operation test data related on power generation electricity and capacity factor of 50 kWp system, which have been collected since 1999, were analysed. From the analysing results, 57.7 MWh in annual power generation electricity of 50 kWp photovoltaic system in 1999 has been decreased 49.1 MWh in 2005 and reached 38.0 MWh in 2010. In addition to, the capacity factor of 50 kWp photovoltaic system also showed 13.2 % in 1999, 11.2% in 2005 and finally reached 8.8% in 2011. The operation test data showed a trend of decreasing of generation electricity and capacity factor during the 12 years operation time and we guessed that was caused by solar cell performance degradation and decreasing of PCS system efficiency.

• 한국태양에너지학회:학술대회논문집
• /
• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
• /
• pp.172-177
• /
• 2008

This study was carry out evaluation of long-term performance for the decentralized desalination system with the solar thermal system and the photovoltaic power system. First operating demonstration system was set up in Cheju in 2006. These system comprises the desalination unit with designed daily fresh water capacity of $2m^3$ and is supplied by a $120m^2$ evacuated tubular solar collector, a $6m^3$ heat storage tank, and a 5kW photovoltaic power generation supply the electricity for hydraulic pumps to move the working fluids. In a clear day more than 400W/$m^2$, the daily fresh water showed to produce more than about 500liter, and from January, 2007 to October, 2008 for 2 years, solar irradiance daily averaged was measured 370W/$m^2$, the daily fresh water yield showed that can be produced about 330liter.

• 한국인터넷방송통신학회논문지
• /
• 제20권3호
• /
• pp.1-7
• /
• 2020

증가하는 사이버공격에 대응하기 위하여 머신러닝을 적용한 자동화된 침입탐지기술이 연구되고 있다. 최근 연구결과에 따르면, 순환형 학습모델을 적용한 침입탐지기술이 높은 탐지성능을 보여주는 것으로 확인되었다. 하지만 단순한 순환형 모델을 적용하는 것은 통신이 중첩된 환경일수록 연관된 통신의 특성을 반영하기 어려워 탐지성능이 저하될 수 있다. 본 논문에서는 이 같은 문제점을 해결하고자 세션관리모듈을 설계하여 LSTM(Long Short-Term Memory) 순환형 모델에 적용하였다. 실험을 위하여 CSE-CIC-IDS 2018 데이터 셋을 사용하였으며, 정상통신비율을 증가시켜 악성통신의 연관성을 낮추었다. 실험결과 통신연관성을 파악하기 힘든 환경에서도 제안하는 모델은 높은 탐지성능을 유지할 수 있음을 확인하였다.

• 지역사회간호학회지
• /
• 제24권3호
• /
• pp.332-345
• /
• 2013

Purpose: This study was attempted to provide quality improvement and revitalization of visiting nurse services by Importance-Performance Analysis of persons being provided with the services. Methods: The subjects were 350 people being provided with visiting nurse services from a long term home care institution in the kangwon Province during the period of data collection between Aug. 16 and Sep. 15, 2011. Data analysis was conducted through t-test, ANOVA, and IPA by using the SPSS/WIN 12.0 program. Results: As a result of the Importance-Performance Analysis of visiting nurse services, it turned out that the strength on reliability, assurance, and empathy should be maintained with good work and the aspects of responsiveness appeared to be intensively improved, and the tangibility proved to be subject to improvement. Conclusion: For the activation of visiting nurse services, methods for improving the performance in the intensive care area and management strategy establishment which highlights the advantages of strength maintenance area are needed.