In this study, the fatigue behavior of reinforced concrete beams strengthened with prestressed NSM CFRP tendons. One of test objectives is to find out strengthening effect with concrete strength 20MPa, 40MPa. As a result of the study, the fatigue behavior of the concrete beams strengthened with prestressed NSM CFRP tendons were considered to be good.

This paper presents the basic data for the structural safety study of the extension wall by evaluating the bending stresses of the existing and extension walls varying according to the plan change of the extension building through the numerical analysis on the horizontal load as follows: 1) the stress variation of the divided wall when the wall opening due to a partial demolition is evaluated by comparing the result of analysis on whether or not the opening of the bearing wall is demolished as a variable; 2) the stress variation of the existing wall due to the increase of the stiffness of the extension wall is also evaluated by comparing the result of analysis on the thickness of the extension wall as a variable.

Recently, because of the increased needs for isolation device structure, a lot of buildings equipped with isolation systems are designed. In this paper, we provide the information about the seismic isolation effects due to the stiffness variation of isolation devices due to the manufacturing errors for middle layer seismic isolation.

도시유역의 중·하류부에 주로 설치되는 4방향 합류맨홀에서 과부하 흐름에 의한 에너지 손실은 도심지 침수피해를 가중시키는 주요 원인이다. 과부하 4방향 합류맨홀에는 유입관의 유입조건에 따라 흐름 양상이 크게 변화되며, 중간맨홀 뿐만 아니라 3방향(T형) 합류맨홀의 흐름조건을 구성한다. 그러므로 유입관의 유입유량 변화에 따른 과부하 4방향 합류맨홀의 에너지 손실 변화 분석 및 손실계수 산정이 필요하다. 본 연구에서는 하수도시설기준을 준용하여 맨홀직경 및 관경을 1/5로 축소 한 수리실험 장치를 제작하였다. 과부하 사각형 4방향 합류맨홀에서 유입관의 유입유 량비 변화에 따른 손실계수를 산정하기 위하여 유입관(주 유입관 및 양측면 유입관)의 유입유량비를 10% 간격으로 변화시켜 다양한 유량조건(40 case)을 선정하였다. 실험 결과 중간맨홀에서 0.40의 가장 낮은 손실계수가, 90° 접합맨홀에서 1.58의 가장 높은 손실계수가 산정되었다. 또한 합류맨홀(T형, 4방향)의 경우 측면 유입유량이 한쪽으로 편향될수록 보다 큰 손실계수를 나타냈다. 유입관의 유입유량 조건 변화에 따른 손실계수를 산정하여 손실계수 범위도를 작도하였으며, 과부하 사각형 4방향 합류맨홀에서 모든 흐름조건을 고려할 수 있는 손실계수 산정식을 제시하였다. 제시된 산정식은 유입관의 유입유량이 변화하는 배수시스템의 설계 및 검증에 적용이 가능할 것으로 판단된다.

A total of 447 accessions consisting of seven Brassica spp.; Brassica carinata (34), B. juncea (199), B. rapa subsp. dichotoma (18), B. rapa. subsp. oleifera (14), B. rapa subsp. rapa (36), B. rapa subsp. trilocularis (56) and B. alba subsp. alba (90) were studied for their morphological characters and fatty acid compositions. There was a wide variation for morphological traits, oil content and fatty acid composition among Brassica species. Seed number/silique and yield/plant were varied from 4.2 (B. alba) to 25.1 (B. rapa subsp. trilocularis) and from 170.7 g (B. rapa subsp. oleifera) to 351.9 g (B. juncea L. Czern.), respectively. Among Brassica species, B. rapa subsp. trilocularis exhibited the highest oil (29.2%), stearic (20.4%) and erucic acid (45.3%) content. B. carinata had the highest content of palmitic (5.2%), oleic (21.2%) and linolenic acid (11.1%). B. rapa subsp. dichotoma and B. rapa subsp. oleifera exhibited the highest content of linoleic (8.1%) and behenic (26.9%) acid, respectively. B. rapa subsp. trilocularis exhibited the highest (45.3%) erucic acid content and significant positive relationship was observed between oleic acid and linoleic acid. This variation of agronomic and fatty acid compositions in Brassica species can be utilized to develop new varieties.

The electric coupling between the lithosphere and the ionosphere is examined. The electric field is considered as a timevarying irregular vertical Coulomb field presumably produced on the Earth’s surface before an earthquake within its epicentral zone by some micro-processes in the lithosphere. It is shown that the Fourier component of this electric field with a frequency of 500 Hz and a horizontal scale-size of 100 km produces in the nighttime ionosphere of high and middle latitudes a transverse electric field with a magnitude of ~20 mV/m if the peak value of the amplitude of this Fourier component is just 30 V/m. The time-varying vertical Coulomb field with a frequency of 500 Hz penetrates from the ground into the ionosphere by a factor of ~7×105 more efficient than a time independent vertical electrostatic field of the same scale size. The transverse electric field with amplitude of 20 mV/m will cause perturbations in the nighttime F region electron density through heating the F region plasma resulting in a reduction of the downward plasma flux from the protonosphere and an excitation of acoustic gravity waves.

It is important for radish to have late flowering characteristics especially in the case of spring and winter cultivars. To understand late flowering characteristics of radish at the molecular level the flowering time genes of two radish lines (NH-JS1 and NH-JS2) with different flowering time were compared by re-sequencing their genomes. There were a total of 872,587 SNPs and 194,637 INDELs between the two lines. The SNP density of each chromosome was relatively uniform throughout, but the region with low SNP density was found at the end of R3 and the middle of R9. To compare the flowering time genes of the two lines, we first looked for the flowering time genes in radish using Arabidopsis thaliana flowering time genes. As a result, homologs of radish were found for most flowering time genes, but FRIGIDA was not found. Among 224 radish flowering time gene-homologs found, 97 genes showed more than one sequence difference (SNP or INDEL) between the two lines, and 127 genes had no difference. In particular, no sequence differences were found in FT, CO, and FLC, core flowering time control genes. Rs350520 (FVE), Rs193800 (CURLY LEAF) and Rs255320 (ATX1) with more than 100 sequence variations were expected to have a significant effect on flowering time difference between the two lines. These results will be of great help in understanding the flowering timing difference between the two lines at the molecular level.

Numerical analysis using commercial CFD code was carried out to develop the drag force type vertical axis hydraulic turbine for the improvement of the production efficiency of small hydro energy at low flow velocity condition. Blade pressure changes and internal flows were analyzed according to the presence or absence of the hydraulic turbine blade holes at flow velocity of less than 1.0~3.0 m/s. According to the numerical results, the pressure and flow velocity is severly affected by the flow velocity in turbine blade with no holes, while the influence of flow velocity is comparatively decreased in turbine blade with holes. It is also found that the pressure and flow velocity on the blade surface with holes are evenly distributed with no singular location and it is believed that forming a hole in the blade may be helpful in terms of structural safety.

This paper presents a mathematical model derived from the upper-bound theorem of concrete plasticity to rationally evaluate the shear friction strength of concrete interfaces with a construction joint. The upper limit of the shear friction strength was formulated from the limit state of concrete crushing failure on the strut-and-tie action along the construction joints to avoid overestimating the shear transfer capacity of a transverse reinforcement with a high clamping force. The present model approach proposed that the cohesion and coefficient of friction of concrete can be set to be 0.27(fck)0.65 and 0.95, respectively, for rough construction joints and 0.11(fck)0.65 and 0.64, respectively, for smooth ones, where fck is the compressive strength of concrete. From the comparisons with 155 data compiled from the available literature, the proposed model gave lower values of standard deviation and coefficient of variation of the ratios between predictions and experiments than AASHTO and fib 2010 equations, indicating that the proposed model has consistent trends with test results, unlike the significant underestimation results of such code equations in evaluating the shear friction strength.

폐기물매립지에서 함수율은 폐기물의 분해속도뿐만 아니라 폐기물의 분해율에도 영향을 미치는 것으로 알려져 있으며, 이에 매립지 내부의 수분을 인위적으로 증가시켜 매립가스 발생량을 증대시키는 bioreactor 공법이 연구되고 있다. 따라서 향후에는 국내외 매립가스 자원화를 계획 및 진행하고 있는 폐기물매립지를 대상으로 bioreactor 공법이 적용될 것으로 예상되며, 이를 위해 매립지 내부의 함수율 변화에 따른 매립가스 발생특성이 예측되어야 할 것이다. 그러나 기존 연구들에서는 실내실험 및 현장 실증실험을 통하여 bioreactor 공법 적용에 따른 조기안정화 및 매립가스 발생량 증대 효과만을 나타내었을 뿐 함수율 변화가 폐기물의 분해도 및 분해속도에 미치는 영향을 수치적으로 나타내지 않아 bioreactor 공법 적용에 따른 정확하고 신뢰성 있는 매립가스 발생량 예측이 어려운 점이 있다. 이에 본 연구에서는 매립지 내부에서의 함수율 변화가 메탄발생 특성에 미치는 영향을 평가하여 향후 함수율 변화에 따른 메탄발생량 및 발생속도 예측의 기초자료로 이용하고자 하였다. 시료는 가연물 중 매립지에 가장 높은 비율로 매립되는 종이를 대상으로 하였다. 각 반응조별 초기 함수율은 10%, 20%, 30%, 40%, 50%로 설정하였으며, 초기함수율 10~40%의 반응조들은 가스발생이 중지되었을 때 함수율을 10%씩 증가시켜 최종적으로는 모든 반응조의 함수율이 50%에 도달하도록 실험을 진행하였다. 실험결과 메탄발생이 최초 중지되는 시점의 각 반응조별 메탄발생 비율은 50% 반응조 대비 10%는 0.4%, 20%는 0.8%로 메탄발생이 매우 미미하였으며, 30%는 6.5%, 40%는 28.9%로 매우 적은 메탄발생 비율을 나타내었다. 이후 각 반응조마다 메탄발생이 중지되는 시점에 함수율을 10%씩 증가시켜 모든 반응조의 최종 함수율이 50%가 되도록 하였으며, 실험 종료 후 메탄발생 비율은 초기함수율 50% 대비 10%는 3.5%, 20%는 7.0%, 30%는 25.1%, 40%는 49.6%로 나타났다. 이론적으로는 초기 함수율이 낮아도 최종 함수율이 동일하면 유기물의 분해속도는 달라도 최종 함수율이 나타내는 메탄발생량과 동일한 값을 나타내어야 하나 초기함수율 10~40% 반응조 모두 초기함수율 50%가 나타내는 메탄발생량에 훨씬 못미치는 메탄발생량을 나타내었다. 따라서 메탄발생량과 연관하여 초기함수율은 매우 중요 인자이며, 메탄발생이 중지되는 시점에 수분을 추가로 주입하면 메탄발생이 다시 시작되나 최종 메탄발생량은 초기 함수율이 낮을수록 크지 않을 것으로 판단된다.

다양한 환경에서 수집한 국내 민들레속 유전자원 수집종의 엽록체 DNA 영역(trnL-trnF와 rps16-trnK) 염기서열을 이용하여 종내․ 간 변이 및 배수성을 구명하여 유전자원 육성의 기초 자료룰 제공하고자 수행하였다. 민들레속 유전자원의 배수성은 털민들레, 서양민들레, 붉은씨서양민들레가 3배체이고, 흰 민들레와 흰노랑민들레는 4배체였다. 염기서열의 길이는 trnLtrnF 영역에서 자생종류인 털민들레, 흰민들레, 흰노랑민들레 가 931 bp에서 935 bp, 서양민들레는 910 bp, 붉은씨서양민들레 는 975 bp로 종간 차이를 나타내었고, 종 특이적 염기서열 88개, 자생종 및 귀화종 특이적 염기서열 41개가 검출되었다. rps16- trnK 영역은 털민들레 882∼883 bp, 흰민들레 875∼881 bp, 흰 노랑민들레는 878∼883 bp 서양민들레 874∼876 bp, 붉은씨서 양민들레는 847∼848 bp로 37개 종특이적 염기서열이 검출되 었다. 염기서열의 유사도는 trnL-trnF 영역에서 0.860∼1.000 사이로 평균 0.949이며, rps16-trnK 영역의 유사도는 0.919∼ 1.000 사이로 평균 0.967이었다. 염기서열을 바탕으로 유연관계를 분석한 결과, trnL-trnF 영역은 크게 자생종류와 귀화종 류로 구분되었으며, 서양민들레와 붉은씨서양민들레는 같은 종 간에 유집되었고, 자생종류는 분리되지 않았으며, rps16-trnK 4개 그룹과 유집되지 않은 5개체로 나뉘었다. 흰노랑민들레는 두 영역 모두 흰민들레와 동일 계통군을 형성하였고, 염기서열 상 두 종간 뚜렷한 차이가 없었다. 유연관계에서 모두 독립적으로 존재한 흰민들레 No. 10 (조계산)과 털민들레 1번(광양)은 민들레 유전자원 육성소재로 활용이 기대된다.

최신 영상 기법인 MAGiC sequence의 RF coil channel 수 변화에 따른 T1, T2 이완 시간 및 T1, T2 이완율 을 측정하여 분석하였고 그에 따른 재현성을 평가하였다. Channel 수가 각각 (1, 8, 16, 32)channel 인 RF coi l에 조영제 phantom(1.0, 0.6, 0.2, 0mM)을 위치시키고 MAGiC sequence를 이용하여 T1, T2, R1, R2 map을 획 득하였다. 그리고 각각의 channel 수와 농도별로 T1, T2, R1, R2 value 그리고 relaxation rate를 측정하였고 이를 기반으로 각 농도에 따른 Relaxivity를 구하였다. 각각의 coil에서 T1, T2, R1, R2 value를 측정한 결과 T1, R1 value는 coil간의 유의한 차이가 없었다(p>0.05). 하지만 T2, R2 value는 유의한 차이가 있는 것으로 나타났다(p<0.05). 사후분석 결과에서는 T2 value의 경우 1 channel coil에서 측정한 결과가 8, 16, 32 channel coil에서 측정한 결과와 유의한 차이가 나타났고(p<0.05) 8, 16, 32 channel coil간의 차이는 나타나지 않았다 (p>0.05). R2 value의 경우도 마찬가지로 1 channel coil에서 측정한 결과가 8, 16, 32 channel coil에서 측정한 결과와 유의한 차이가 나타났으며 또한 8 channel coil에서 측정한 결과와 16 channel coil에서 측정한 결과 가 유의한 차이가 나타났다(p<0.05). 결론적으로 T1, R1 value는 coil의 channel 수 변화에 따른 차이가 크지 않지만 T2, R2 value는 큰 차이를 나타냈다. 따라서 MAGiC sequence를 이용하여 T2, R2 value를 정량적으로 측정할 경우 재현성을 위해 동일한 channel 수의 coil을 사용해야 할 것으로 사료된다.

For high-quality colored rice production, the cultivation environment is a critical factor. The major environmental factor is temperature, which includes the accumulated and average temperature during vegetative and reproductive stages. Generally, during the cultivation period, the temperature can be controlled by shifting the transplanting date. This study was carried out to determine the optimum transplanting date for high-quality red-colored rice production. Four red-colored rice varieties (Jeokjinju, Jeokjinjuchal, Hongjinju, and Gunganghongmi) were used as test materials. The transplanting dates were May 20 and June 5, 20, and 30 in 2015~2016. The most variable factor controlled by the transplanting date was the grain filling rate. The varieties transplanted on June 30 showed low yields owing to the decrease in the grain filling rate. In contrast, the polyphenol content increased with increasing delay in the transplanting date. Collectively, these two results indicate that the optimum transplanting date was June 20. The average temperature for 30 days after the heading date (30DAH) highly affected the polyphenol content. A lower temperature during the 30DAH induced higher polyphenol contents but also caused low yield. The optimum 30DAH temperature for obtaining a higher yield and polyphenol content was 22~23°C. Using the average 30DAH and accumulated temperatures, the optimum transplanting date was calculated as June 18 to 24 in Miryang region. The optimum transplanting date of Kyeungsangnamdo region was approximately mid-June to early July, and that of Kyeungsangbukdo region was approximately early to mid-June.

Magnesium is important not only for the growth of rice itself, but also as an essential micronutrient component of half of the world population who are supported by rice. Here, we performed genome-wide association study (GWAS) with high-resolution density SNPs to identify natural allelic variation in Mg2+ increase from rice set, which is derived from a total 24,368 rice germplasms. The range of the concentration and distribution of Mg2+ in 295 core accessions of brown rice grain were wide, from 18.17mg/L to 57.11mg/L, with mean 39.71mg/L. In particular, GWAS result shows that the high peak found on chromosomes 3 and 11. The new natural variants identified through haplotyping analysis would be useful to develop new rice varieties with improved storage ability of the valuable mineral through the future molecular breeding.

Due to recent climate changes, damage to the soundproof wall due to typhoons and strong winds is on the rise. This study determine the fragility curve of aluminum frame, which is a weak member of the soundproofing wall, due to strong wind. The fragility was analyzed in term of aluminum frame thickness variation. Finite element analysis of the wall was performed with ABAQUS, a commercial program. Random wind loads applied to the structures were generated using the Monte Carlo simulation technique. Also, the limit state was set based on the analysis results. The fragility curves were developed with consideration of three influential factors which are installation location, wind exposure and thickness aluminium frame of soundproof wall.

Morphological variation between cultivated and weedy types of Perilla frutescens var. frutescens and P. frutescens var. crispa were studied in 327 germplasm by examining 17 morphological characters. The germplasm between the two varieties were varied for their qualitative and quantitative characters. The seed coat color of cultivated P. frutescens var. frutescens is commonly light brown and brown while deep brown color was observed in the weedy type P. frutescens var. frutescens and P. frutescens var. crispa. The leaf size, cluster length, plant height, flower number per cluster and seed weight in cultivated P. frutescens var. frutescens were significantly (P<0.05) different from weedy type P. frutescens var. frutescens and P. frutescens var. crispa. The cultivated P. frutescens var. frutescens exhibited significantly higher plant height (158.6 ㎝) compared to the weedy P. frutescens var. crispa (133.8 ㎝). Likewise, seed weight was significantly higher in cultivated (1.9 g) than in the weedy type of P. frutescens var. frutescens (1.6 g) and P. frutescens var. crispa (1.4 g). Principal component analysis (PCA) result showed that the first and second principal component cumulatively explained 86.6% of the total variation. The cultivated type P. frutescens var. frutescens and its weedy accessions were not clearly separated with P. frutescens var. crispa by PCA. Hence it requires the use of molecular markers for better understanding of their genetic diversity.

The sun is not equally bright over the whole sphere, but rather is darkened toward the limb. This effect is well-known as limb darkening. The limb darkening coefficient is defined by the ratio of the center intensity to limb intensity. In this study, we calculate the limb darkening coefficient using the photospheric intensity estimated from solar images taken by solar and helispheric observatory (SOHO) and solar dynamics observatory (SDO). The photospheric intensity data cover almost two solar cycles from May 1996 to December 2016. The limb darkening coefficient for a size of 0.9 diameter is about 0.69 and this value is consistent with solar limb darkening. The limb darkening coefficient estimated from SOHO shows a temporal increase at solar maximum and a gradual increase since the solar minimum of 2008. The limb darkening coefficient estimated from SDO shows a constant value of about 0.65 and a decreasing trend since 2014. The increase in the coefficient reflects the effect of weakened solar activity. However, the decrease since 2014 is caused by the aging effect.

In this study, we analyzed the changes in the echolocation and prey-capture behavior of the horseshoe bat Rhinolophus ferrumequinum from search phase to capture time. The experiment was conducted in an indoor free-flight room fitted with an ultra-high-speed camera. We found that the bats searched for food while hanging from a structure, and capturing was carried out using the flight membrane. In addition, it was confirmed that the mouth and uropatagium were continuously used in tandem during the capturing process. Furthermore, using Constant Frequency (CF), we confirmed that the prey catching method reflected the wing morphology and echolocation pattern of R. ferrumequinum. The echolocation analysis revealed that the pulse duration, pulse interval, peak frequency, start-FM-bandwidth, and CF duration decreased as the search phase approached the terminal phase. Detailed analysis of echolocation pulse showed that the end-FM bandwidth, which increases as it gets nearer to the capture time of prey, was closely related to the accurate grasp of the location of an insect. At the final moment of prey capture, the passive listening that stopped the divergence of the echolocation was identified; this was determined to be the process of minimizing the interruption from the echo of the echolocation call emitted from the bat itself and sound waves emitted from the prey.

Meteorological characteristics related to variations in ozone (O3) concentrations in the Korean peninsula before, during, and after Typhoon Talas (1112) were analyzed using both observation data and numerical modeling. This case study takes into account a high O3 episode (e.g., a daily maximum of ≥90 ppb) without rainfall. Before the typhoon period, high O3 concentrations in the study areas (e.g., Daejeon, Daegu, and Busan) resulted from the combined effects of stable atmospheric conditions with high temperature under a migratory anticyclone (including subsiding air), and wind convergence due to a change in direction caused by the typhoon. The O3 concentrations during the typhoon period decreased around the study area due to very weak photochemical activity under increased cloud cover and active vertical dispersion under a low pressure system. However, the maximum O3 concentrations during this period were somewhat high (similar to those in the normal period extraneous to the typhoon), possibly because of the relatively slow photochemical loss of O3 by a H2O + O(1D) reaction resulting from the low air temperature and low relative humidity. The lowest O3 concentrations during the typhoon period were relatively high compared to the period before and after the typhoon, mainly due to the transport effect resulting from the strong nocturnal winds caused by the typhoon. In addition, the O3 increase observed at night in Daegu and Busan was primarily caused by local wind conditions (e.g., mountain winds) and atmospheric stagnation in the wind convergence zone around inland mountains and valleys.

본 연구에서는 다공성 매질의 공극율과 투수능 그리고 유체의 동점성 계수와 같은 물리적 특성에 따른 유체흐름의 비선형 거동에 대한 수치적 분 석을 수행하였다. 적용된 수치모형은 ANSYS CFX 3차원 유동해석 모형이며, 모형의 검증은 기존의 물리적 실험 결과 및 수치모의 결과의 적용을 통해 수행되었으며, 적용된 압력경사와 유속과의 관계 그리고 마찰계수와 레이놀즈 수와의 관계에 대해 비교적 잘 일치하였다. 다공성 매질의 공극 율과 투수능 그리고 유체의 동점성 계수의 값을 변화시키면서 모의한 결과 유체의 동점성 계수가 다공성 매질의 유체흐름의 비선형 거동에 가장 큰 영향을 미치는 것으로 나타났다.