• Proceedings of the Korea Water Resources Association Conference
• /
• 2021.06a
• /
• pp.465-465
• /
• 2021

2019년 도시계획현황 통계에 따르면 우리나라 국민의 90% 이상이 도시에 거주하고 있는 것으로 나타났다. 도시의 인구증가는 불투수면적 증가, 표면유출 증가, 침투량감소 등 도시 물순환의 왜곡을 발생시키며 건전한 물순환을 저해시키는 원인이 되고 있다. 본 연구에서는 이러한 도시 물순환을 저해시키는 요인을 평가할 수 있는 지표를 개발하기 위하여 물순환 관련법, 물순환 및 물관리를 위한 조례, 국내외 연구 사례를 조사하였으며 국내에서 수행된 다양한 지표 연구결과물을 분석하였다. 물순환 지표를 특정할 수 있는 6개의 키워드를 선정하여 105건의 논문 및 보고서를 검토하였으며, 최종적으로 49건을 선정하였다. 선정된 문헌별 지표를 수요·공급, 이수·치수, 수질·생태로 구분하여 정보를 분리화 한 후 분리된 정보를 유사한 지표별로 통합하여 세부지표를 도출하였다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.12
• /
• pp.785-792
• /
• 2017

In recent times, the lack of good quality natural aggregate has led to the alternative use of recycled aggregate. However, the adhered mortars in recycled aggregate lower the performance of the concrete, such as by reducing its strength and causing deterioration and cracking. In this study, the effects of nylon fiber (NF) on the mechanical and durable performance of recycled coarse aggregate concrete (RAC) were experimentally examined. Concrete specimens with natural coarse aggregate (NA) or RA were produced by adding 0, 0.6 and $1.2kg/m^3$ of NF. Various mechanical properties and the durability of the RAC were measured and compared with those of the NAC. In addition, in order to observe the hydrates and ITZ, SEM observations were made of the 28-day concrete samples. From the test results, as expected, it was found that the RAC exhibited lower performance than the NAC. However, the addition of NF to the concrete was effective in significantly enhancing the performance of the RAC due to the bridge effect of the NF.

• Journal of Chest Surgery
• /
• v.37 no.9
• /
• pp.793-795
• /
• 2004

Modified Norwood procedure with maintaining cardiac beat was done in a 30-day-old neonate. Procedure was done with regional perfusion of innominate and coronary artery. Postoperative course was uneventful. Second-stage operation (bi-directional cavopulmonary shunt) was done 4 months later. The diameter of ascending aorta was more than 5 mm, Norwood procedure can be done in beating hearts.

• 기계와재료
• /
• v.23 no.1
• /
• pp.34-43
• /
• 2011

최근 노령화와 스포츠 인구의 증가로 인해 족부 혈액순환 장애 및 족관절의 퇴행성 질환이 증가하고 있으며 이로 인해 몸의 평형기능 및 운동성에 기능장애가 동반하게 된다. 이로 인해 일상생활 기능 저하와 낙상과 같은 이차적 합병증 발생을 초래하여 기능 및 삶의 질 저하, 활동제한 등으로 건강한 노년에 대한 심각한 위협 요인이 될 수 있다. 따라서 족부 혈액순환 증진을 위해 IT기술을 활용하여 압력에 따른 부위별 자극의 세기를 달리하고, 3D영상을 통해 가공의 상황 및 가상의 환경을 사람의 감각을 통해 느끼게 하여 실제 상호작용하고 있는 것처럼 만들어 주어, 혈액순환 개선의 효과를 극대화하고자 노화에 따른 족부건강 변화 및 족부 자극의 효과를 분석하고, 가상현실을 기반으로 한 족부혈액 순환 증진 장치와 관련 컨텐츠에 대해 제시하고자 한다.

• Proceeding of EDISON Challenge
• /
• 2016.03a
• /
• pp.625-627
• /
• 2016

본 논문은 EDISON CFD의 전처리기, eMEGA를 이용하여 격자를 생성하고, 2차원 정렬 격자 기반 비압축성 해석자를 이용하여 유동해석을 진행한 뒤 후처리기, eDAVA를 통해 유동선을 그려 블라인드 장착에 따른 실내 공기 순환에 대한 연구 내용을 담고 있다. 본 연구는 시중에 판매중인 사생활 보호용 블라인드를 포함, 여러 블라인드의 장착 여부에 따라 실내 내부 공기 순환의 양상을 확인하고 실제로 블라인드 장착 시 실내환기에 어떤 영향을 주는지 유동 선을 통해 확인해 보았다. 블라인드 미장착시, 실내 전체적으로 공기가 고루 순환되는 모습을 보였으며, 블라인드 장착 시 대체로 블라인드 형태에 따라 유동이 이동하는 것을 볼 수 있었다. 본 연구는 사생활 보호와 환기 효율성의 관점에서의 소비자 선택권에 영향을 미치는 효과를 가져 올 것으로 보인다.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.4 no.1
• /
• pp.1-9
• /
• 2016

While the amount of construction waste has not been changed much in discharge for last 10 years, the recycled resources refined from construction waste have been mainly applied to low-leveled one such as reclamation, back-fill, road base or subbase and so on. Thus this study addresses the applicability of recycled fine aggregate as a replaceable material in precast concrete. To evaluate the possibility, both of dry and wet processes were adopted as well as steam curing, widely used in the field for rapid producing. Most important experimental parameters were driven through preliminary experiments and were evaluated in terms of concrete properties. It is found from aggregate-replacement tests that all of consistency and strengths of concrete were decreased as the ratio of recycled fine aggregate increased, and the amount of decrease can be estimated using proposed equations. Though the recycled fine aggregate showed a decrease of concrete properties more or less, the applicability in large volume as a constituent of precast product was well noted from experimental results.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.5 no.3
• /
• pp.63-69
• /
• 2010

This study investigates the chemical resistance of the recycled aggregate concrete containing calcined ground slag, fly ash, and diatom powder. The recycled aggregate which had the density of $2.48g/cm^3$, the absorption of 4.25%, and standard gradation was used and the concrete specimens were submerged in solutions of $Na_2SO_4$ and $CaCl_2$ at 10% concentration for 6 months. As the submersion result, pore volume of over $0.02{\mu}m$ diameter was formed less in the concrete specimens containing calcined ground slag, fly ash, and diatom powder than in the concrete without the pozzolanic materials and the result shows the effectiveness of the pozzolanic materials for the increase of chemical resistance of the recycled aggregate concrete.

• 한국노년학
• /
• v.29 no.3
• /
• pp.823-835
• /
• 2009

This study was designed to examine the effects of 12 weeks of circuit exercise on obesity, physical fitness and metabolic syndrome index in elderly obese women. 19 elderly obese women volunteered to participate in and completed the study. Participants went through their exercise program for 30 minutes per session and 3 sessions per week for 12 weeks. Lower(p<.001) and upper extremities strength(p<.05), upper(p<.05) and lower extremities flexibility(p<.01), agility & dynamic balance(p<.001), endurance exercise capacity(p<.05) were significantly increased after 12 weeks circuit training. Also, Body weight(p<.001), BMI(p<.001) & Metabolic syndrome index as waist circumference(p<.01), systolic BP(p<.05), TG(p<.001), HDL-C(p<.01), glucose(p<.05) were significantly differenced between pre and post. It was concluded that circuit exercise program has positive effects on body composition, physical fitness and metabolic syndrome index in elderly obese women.

• Journal of The Korean Association For Science Education
• /
• v.40 no.3
• /
• pp.237-251
• /
• 2020

Issues on climate change we are facing, such as global warming, are very important as it affects our lives directly. To overcome this, efforts to reduce greenhouse gases emissions (e.g., carbon dioxide) are necessary and these efforts should be based on our integrated understanding of carbon cycle. The purpose of this study is to examine the research trend on carbon cycle education and to suggest the value and direction of carbon cycle education for students who will be citizens of the future. We analyzed 52 carbon cycle education related studies collected from academic research databases (RISS, KCI, ERIC, Google Scholar, and others). As a result, we conclude that resources are still limited and more researches on verification and utilization of developed program, development of accurate and comprehensive tools for students' recognition and level assessment, developing educational model or teacher professional development, providing more appropriate curriculum resources, and the use of various topics or materials for carbon cycle education are necessary. Students' comprehensive understanding of the carbon cycle is important to actively react to the changes in the global environment. Therefore, to support such learning opportunities, resources that can be connected to students' daily experiences to improve students' understanding of carbon cycle and replace misconceptions based on the verification of existing programs should be provided in the classroom as well as the curriculum. In addition, sufficient exemplary cases in carbon cycle education including various materials and topics should be provided through professional development to support teachers teaching strategies with carbon cycle.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.10 no.4
• /
• pp.475-481
• /
• 2022

Recycled aggregates show high water absorption rate compared to natural aggregates due to microcrack developed during production process and adhered cement pastes at the surface of recycled aggregates. This leads to the deterioration of mechanical properties and slow work flow. Currently it is getting hard to satisfy high demand for natural aggregates. Utilizing recycled aggregate more widely may be a substitutable countermeasure for the shortage of natural resources. In this study, two-stage mixing approach(TSMA) suggested by Tam et al. is used to produce recycled aggregate concrete(RAC) with 100 % replacement of coarse natural aggregate and tests for compressive strength, elastic modulus, and chloride ion diffusion coefficient are conducted to find out the effect of TSMA compared to normal mixing method. According to experimental result compressive strength and elastic modulus of RAC with TSMA was superior to those of RAC with normal mixing irrespective of water-cement ratio, and in some cases mechanical properties of RAC with TSMA approached to those of natural aggregate concrete(NAC). However, chloride ion diffusion coefficient of RAC was higher than that of NAC. This illustrates that TSMA is not an appropriate method in reducing chloride ion diffusion coefficient, resulting in inconsequential contribution of TSMA to the durability of RAC.