With the development of national industry, the number of social infrastructure facilities is gradually increasing. In addition, as time goes by, the aging of facilities is progressing gradually. For this reason, the importance of maintenance to ensure the safety of facilities is continuously increasing. However, there is still a lack of effective ways to invest the maintenance budget of facilities. For this reason, advanced foreign countries are actively studying facilities asset management techniques. In this study, construction cost and depreciation method of existing major facilities(1,2 class) were applied to examine the asset size of existing facilities according to changes in the service life of facilities.

The spaces under bridge have been used as business zone and yard. The facilities and piles of goods under bridges are considered at high risk for fire danger. In this paper, CFD simulations were conducted to predict the temperature change beneath steel and concrete bridges due to fire in clothing boxes, frequently placed in the space under bridge. Based on these results, the relationship between the piled height of clothing boxes and the clearance of bridge, and temperatures beneath the bridge was derived using a Lagrange interpolation.

This paper presents evaluation of diffusion coefficient, passed charge, and compressive strength considering 3 substitution ratios of fly ash(0%, 30%, and 50%) and 3 different W/B ratios(37%, 42%, and 47%). Also, the relationships among diffusion coefficient, passed charge, and compressive strength are investigated focusing on the results at 28 days and 180 days. With increasing replacement ratio of FA and decreasing W/B, the resistances to chlorides(diffusion coefficient and passed charge) are improved. At 28 days and 180 days, linear relationship are observed between strength and resistance to chloride on the whole.

Phase change material (PCM) has been developed and applied in various fields as construction material. If the application of PCM as the semi-rigid pavement cement grout becomes available, it would be possible to control the occurrence of a micro crack due to the generation of hydration heat in the ultra rapid harding cement, and if the occurrence of a micro crack is reduced, it would be possible to improve the cohesion performance between asphalt matrix and grout as well as to compact the matrix of the pavement material, improving the durability. Therefore, the applicability review of PCM for the purpose of improving the semi-rigid pavement materials through the shrink reduction of ultra rapid harding cement used as the semi-rigid pavement cement grout was carried out in this study.

This paper investigates the effect of amount of Paraffin-encapsulated phase change material (PCM) on the thermal energy storage of cement mortar for developing energy saving concrete. The PCM with melting point of 44℃ was used in this study. The added amounts of PCM in the cement mortar were 0, 10, 20 and 30% of cement weight. The results indicated that the heat storage properties of cement mortar was improved with increasing contents of PCM.

The failure of piping in nuclear power plants and various plant facilities is mainly caused by vibration due to fluid pressure, dead load, temperature expansion and earthquake load in the pipe. Repeated stresses due to vibration cause local fatigue failure on pipe joints where stress is concentrated, which is a factor that hinders the safety of the structure. Therefore, the vibration problem is solved by installing devices to solve the vibration problem in the pipe where vibration frequently occurs. In this study, we developed a damper that damps the dynamic load generated by piping using the friction pendulum principle, and analyzed the behavior curve of the MER-Spring specimen to be used.

Reinforced concrete is used as a main construction because it is excellent durability and strength. However, the problem of durability decrease due to enlargement, high-rise of structures and the cracking due to external force nowadays. Therefore, there is studying on the Textile Reinforced Concrete(TRC), which reinforcing bar changing into Textile. Also, studying on adhesion performance between concrete and Textile. Preceding studies have examined the adhesion performance of single fibers with no specific variable. It can not reflect about grid type and embedding length. Accordingly, on this study examines the change of bond strength according to bond length. As a result, the bond strength increased as the embedding length of the Textile increased, but there was not influence that the bond strength according to the lateral length.

To certificate change in the geochemical characteristics of surface sediments in the main stream of the Nakdong River, surface sediments from 12 sampling sites during the first and second half year (total 24 sampling sites) were collected and analyzed for grain size, ignition loss, total organic carbon and heavy metal content. Surface sediments mainly composed of sand (coarse and medium sand) and fining changed from the first half to the second half of the year. Ignition loss, total organic carbon and heavy metals content increased in the second half of the year. Some heavy metals (Zn, Ni and Cu) were found to be at the lowest effect levels according to Ontario sediment quality guidelines. Additionally, most heavy metals were found to be at the non polluted level and level I according to USEPA sediment quality standards and National Institute of Environmental Research sediment pollution evaluation standard, respectively. The enrichment factor (< 1) and index of geoaccmulation (< 0) were non polluted in the study area. The correlation analysis results showed that ignition loss, total organic carbon and heavy metal content were highly correlated with grain size. Regarding changes in geochemical characteristics of surface sediments in the study area, grain size fine and organic matter and heavy metal content increased in the second half year. Nonetheless these results indicated pollution levels that did not adversely affect the benthos.

In this study, we investigated variations in particle size distribution in the process flow from a fluff-SRF manufacturing process in Y city via particle size analysis of waste. About 110 kg of MSW was analyzed in accordance with the process flows for the analysis of the particle size distribution by separating from 300 mm to 10 mm. The first tranche of waste was crushed with a primary crusher such that 100% of particles were smaller than 200 mm. A secondary crusher was used to ensure that 90% of particles were smaller than 10 mm. The crushing function and disintegration effect resulted in waste that contained 30% particles smaller than 10 mm. The primary multistage bulk selection process separated the first non-combustibles from waste passed by the secondary crusher. It produced 19.24% non-combustibles. Secondary multistage bulk selection discharges the final set of non-combustibles from the first non-combustibles after recovering any remaining combustibles. The combustible recovery ratio was 28.24%, and the final non-combustible discharge ratio was about 71.76%. The regular and high-speed disintegrators exhibited 85% and 97% efficiency in producing waste smaller than then 50 mm, respectively. This is thought to improve the yield and quality of SRF in the context of a reasonable management plan via characteristic analysis of residues from the disintegration process.

In this paper, for selected station of 8 clusters in East Asia (Park, 2017) more (less) warming periods than the wintertime mean warming of intra-seasonal fluctuation curves were taken and their means were computed. Long term trends and synoptic features of the mean temperature changes were examined. In most clusters, around the third of January there were less warming periods (LWP) than the mean wintertime warming. On the contrary, in February and the first and second of January there were more warming periods (MWP) than the winter mean or LWPs having a warming trend with statistical signicance. Time series of the daily Siberian High indices showed they had been weakening in February and being stagnant around late January. In most stations, the mean temperatures of MWP or LWP had large negative correlation coecients with the Siberian high intensity. is result explains the occurrences of MWPs in most clusters in February and LWPs in late January. In cluster B there were LWPs in early February due to the influence of the Aleutian Low which were strengthening in that periods. Cluster E showed different features without LWPs in late January. The cluster is considered to be affected by its plateau environment of West Yúnnán and the Tibet Plateau which prevent cold air of the lower atmosphere in Northern Asia flowing southward, and by the regional atmospheric circulation of 500hPa surface centered in this region.

In this study, the spatio-temporal variations and trends of frost events (total frost days, first/last frost date) in South Korea were investigated using RegCM4.0 simulation data based on two RCP(4.5, 8.5) scenarios. To evaluate the performance of RegCM4.0 for the current (1981-2010) frost events, the daily minimum temperature of 49 observation sites in South Korea were used. Generally, the RegCM4.0 reasonably simulated the spatial characteristics of frost events, but the first (last) frost date was simulated by about 6.6 (3.3) days earlier (later) than that of the observation. As the results, the simulated number of the total frost days was 10.8 days greater than that of the observation. In the mid- 21st century(2021-2050), the first(last) frost date was projected to be delayed (bring forwarded) by about 7.9(3.1) days in RCP4.5 and about 9.6(2.3) days in RCP8.5, respectively. And the first(last) frost date in the late 21st century(2071-2100) is projected to be delayed (bring forwarded) by about 14.5(15.0) days in RCP4.5 and about 22.2(23.5) days in RCP8.5, comparing to the current climate. These changes could induce a significant decrease of the number of total frost days by about 26.5(47.7) days in the late 21st century under RCP4.5(RCP8.5). And the interannual variability of frost events under RCP4.5(RCP8.5) was projected to be relatively higher(smaller) in the mid-21st century than in the late 21st. The results indicated that the extreme frost events is expected to increase in the mid-21st century under RCP4.5, while in the late 21st century under RCP8.5, comparing to the current climate.

In this study, the intra-seasonal fluctuation (ISF) of wintertime temperature change in East Asia was classified by a cluster analysis of complete linkage. A ISF of temperature change was defined as a difference of synthesized harmonics (1 to 36 harmonic) of daily temperature averaged for 30 years (1951~1980, 1981~2010). Eight clusters were gained from the ISF curves of 96 stations in East Asia. Regions of the cluster C, G and A1 seem to be affected by the Siberian High (SH) center, whereas the cluster A1, A2, D, B and F by the SH main pathways. Regions of the cluster E are apart from the SH main pathways and appear to be in the area of influence of other factors. Wintertime temperatures in Northwest China (clusters C, G) and Northeast China (cluster A1) were increased very largely. In most clusters, around late January there were less warming periods than the winter mean of the mean ISF of the clusters, before and after this time there were more warming periods than the winter mean.

뜰보리수 열매 식초 발효 중 이화학적 특성, 생리활성물질(flavonols과 phenolic acids) 및 생리활성 변화를 조사하였다. 자연 발효 중 pH와 환원당은 발효 초기 각각 3.55와 6.88 mg/mL에서 3.34와 2.13 mg/mL로 감소하였고, 반면에 산도는 0.48%에서 5.48%로 증가하였다. 알코올 함량은 20일째까지 증가하여 6.6%로 최대치를 나타낸 후 감소하여 발효 종기 2.0%를 나타내었다. 초산균수는 발효 10일째 4.32 log CFU/mL에서 5.4 log CFU/mL로 증가하였고, 효모균수는 3.23 log CFU/mL에서 5.5 log CFU/mL로 증가하였다. 뜰보리수 열매 식초의 주요 유기산은 초산, 젖산 및 사과산으로 각각 38.84 mg/mL, 4.92 mg/mL 및 1.51 mg/mL를 함유하고 있었다. 수용성 phenolics와 flavonoids 함량은 발효 중에 증가하여 발효 초기 각각 0.79 mg/mL과 0.12 mg/mL에서 1.22 mg/mL과 0.14 mg/mL로 증가하였다. Flavonols 화합물 중 epicatechin gallate는 발효 10일째 168.1 μg/mL에서 115.97 μg/mL로 감소하였으나, phenolic acids 화합물 중 gallic acid는 18.52 μg/mL에서 95.07 μg/mL로 증가하였다. 자연 발효 60일째 DPPH 라디칼 소거활성은 71.35%, ABTS 라디칼 소거활성은 79.27%, hydroxyl 라디칼 소거활성은 68.72%, α-glucosidase 저해활성은 85.42%, α-amylase 저해활성은 52.12% 및 pancreatic lipase 저해활성은 53.66%를 나타내었다.

본 연구는 강건성 지수와 불확실성 분석기법을 활용하여 기후변화 취약성 평가과정에서 발생하는 불확실성을 정량화하였다. 본 연구는 우리나 라의 6개 광역시(부산, 대구, 인천, 광주, 대전, 울산)를 대상으로 다기준 의사결정기법 중 하나인 TOPSIS 기법을 이용하여 용수공급 취약성 순위를 산정하였다. 강건성 지수는 두 대상 도시의 순위가 가중치의 변화로 인해 순위역전현상이 발생할 수 있는 가능성을 정량화하고 불확실성 분석 기법 은 두 도시 사이에 순위역전이 발생할 수 있는 가중치의 최소 변화량을 산정한다. 그 결과 인천과 대구는 용수공급 측면에서 취약한 것으로 나타났 으며, 대구와 부산은 용수공급 취약성에 민감한 것으로 나타났다. 따라서 대구는 다른 대안에 비해 상대적으로 용수공급이 취약한 지역으로 나타났 으나, 취약성에 민감하기 때문에 기후변화 적응대책 수립 및 시행을 통해 취약성이 크게 향상될 수 있을 것으로 판단된다. 본 연구는 기후변화와 용 수공급 측면에서의 적응전략을 계획하고 수립하는데 있어서 우선적으로 고려해야하는 방향을 제안하는 데 사용될 수 있다.

최근 동위원소를 이용한 뼈 스캔 (Bone Scan)검사 후 골밀도 (BMD; Bone Mineral Density)검사를 당일검사로 병행한 경우 이로 인한 골밀도 측정값에 오차 발생 가능성이 제기되고 있으나 방사성의약품 표지화합물 투여 후 이중에너지 X선을 이용한 골밀도 측정값 변화에 대한 임상적 자료가 미비하여 핵의학 체내 검사 후 당일 골다공증 검사의 측정값에 대한 논란의 소지가 있다. 따라서 동위원소 표지화합물인 99mTc-MDP가 골밀도 측정값에 영향을 미치는지 임상적 측면에서 실험하였다. 실험에 참가한 대상자의 평균 나이는 35.17±9.45세로 실험 대상자 17명 중 대사성 질환과 골밀도 측정에 영향을 줄 수 있는 허리뼈 압박골절 및 몸쪽 넓적다리뼈 골절이 있는 자를 제외한 12명 중 정상 골밀도 T-scores〉-1.0의 환자 6명을 대상으로 99mTc-MDP 투여 전·후 측정값을 분석한 결과 허리뼈에서 전·후 각각 평균 0.975±0.084 g/cm², 0.966±0.078 g/cm²으로 0.009 g/cm² 증가, 우측 몸쪽 넓적다리뼈에서는 전·후 각각 평균 0.909±0.078 g/cm², 0.913±0.086 g/cm²으로 0.004 g/cm² 감소, 좌측 몸쪽 넓적다리뼈에서는 각각 평균 0.887±0.099 g/cm², 0.881±0.103 g/cm²으로 0.007 g/cm²의 증가를 보여 몸쪽 넓적다리뼈 보다 허리뼈에서 더 큰 골밀도 변화를 보여주었다. 그러나 허리뼈와 몸쪽 넓적다리뼈 전체에서 전·후 변화 평균은 0.0038±0.014 g/cm²으로 골밀도 측정값에 유의한 영향이 없음을 알 수 있으며, 또한 두 실험간 전체 상관계수는 0.987으로 방사성동위원소 표지화합물인 99mTc-MDP 투여가 골밀도 측정값에 영향을 주지 않았다. 따라서 140 keV의 감마선 에너지를 방출하는 테크네슘 표지화합물을 이용한 뼈 스캔검사 후 골밀도 측정값에 유의한 영향을 미치지 않음을 확인하였다. 그러나 핵의학적 체내검사와 골다공증 검사를 당일로 검사함으로 인한 환자의 피폭을 고려한다면 시간 간격을 두고 검사를 시행하는 것이 좋을 것으로 사료된다.

With the development of national industry, the number of social infrastructure facilities is gradually increasing. In addition, as time goes by, the aging of facilities is progressing gradually. For this reason, the importance of maintenance to ensure the safety of facilities is continuously increasing. However, there is still a lack of effective ways to invest the maintenance budget of facilities. For this reason, advanced foreign countries are actively studying facilities asset management techniques. In this study, construction cost and depreciation method of existing major facilities(1,2 class) were applied to examine the asset size of existing facilities according to changes in the service life of facilities.

The spaces under bridge have been used as business zone and yard. The facilities and piles of goods under bridges are considered at high risk for fire danger. In this paper, CFD simulations were conducted to predict the temperature change beneath steel and concrete bridges due to fire in clothing boxes, frequently placed in the space under bridge. Based on these results, the relationship between the piled height of clothing boxes and the clearance of bridge, and temperatures beneath the bridge was derived using a Lagrange interpolation.

This paper presents evaluation of diffusion coefficient, passed charge, and compressive strength considering 3 substitution ratios of fly ash(0%, 30%, and 50%) and 3 different W/B ratios(37%, 42%, and 47%). Also, the relationships among diffusion coefficient, passed charge, and compressive strength are investigated focusing on the results at 28 days and 180 days. With increasing replacement ratio of FA and decreasing W/B, the resistances to chlorides(diffusion coefficient and passed charge) are improved. At 28 days and 180 days, linear relationship are observed between strength and resistance to chloride on the whole.

Phase change material (PCM) has been developed and applied in various fields as construction material. If the application of PCM as the semi-rigid pavement cement grout becomes available, it would be possible to control the occurrence of a micro crack due to the generation of hydration heat in the ultra rapid harding cement, and if the occurrence of a micro crack is reduced, it would be possible to improve the cohesion performance between asphalt matrix and grout as well as to compact the matrix of the pavement material, improving the durability. Therefore, the applicability review of PCM for the purpose of improving the semi-rigid pavement materials through the shrink reduction of ultra rapid harding cement used as the semi-rigid pavement cement grout was carried out in this

This paper investigates the effect of amount of Paraffin-encapsulated phase change material (PCM) on the thermal energy storage of cement mortar for developing energy saving concrete. The PCM with melting point of 44℃ was used in this study. The added amounts of PCM in the cement mortar were 0, 10, 20 and 30% of cement weight. The results indicated that the heat storage properties of cement mortar was improved with increasing contents of PCM.