• International Journal of Highway Engineering
• /
• v.8 no.3 s.29
• /
• pp.129-141
• /
• 2006

The vertical soil pressure developed in the granular layer of asphalt pavement system is influenced by various factors, including the wheel load magnitude, the loading speed, and asphalt pavement temperature. This research observed the distribution of vertical soil pressure in pavement supporting layer by investigating measured data from soil pressure gage in the KHC Test Road. The existing specification of subbase and subgrade compaction was also evaluated with measured vertical pressure. The finite element analysis was conducted to verify the accuracy of results with measured data because it can maximize research capacity without significant field test. The test data was collected from A5, A7, A14, and A15 test sections at August, September, and November 2004 and August 2005. Those test sections and test data were selected because they had best quality. The size of influence area was evaluated and the vertical pressure variation was investigated with respect to load level, load speed, and pavement temperature. The lower speed, higher load level, and higher pavement temperature increased the vertical pressure and reduced the area of influence. The finite element result showed the similar trend of vertical pressure variation in comparison with measured data. The specification of compaction quality for subbase and subgrade is higher than the level of vertical pressure measured with truck load so that it should be lurker investigated.

• Korean Journal of Soil Science and Fertilizer
• /
• v.29 no.1
• /
• pp.60-66
• /
• 1996

Bradyrhizobium japonicum with different colony morphology populated in five Yeongnam soils of Korea was examined for intrinsic antibiotic resistance to eight antibiotics, serological property by immunoblot and immunodiffusion, and protein profile differentiation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Colony morphological distribution of one hundred and twenty B. japonicum isolates was 47% for "dry". 41% for "wet", and 12% for "dry/wet" type. The total isolates showed such a strong correlation between the morphology and antibiotic resistance. Colony morphology, which though was dominantly consisted of the same type within a serogroup, wasn't absolutely linked to serological property of B. japonicum. Based on these data, colony morphology was too simple to identify variations with B. japonicum isolates : antibiotic resistance such complicated compared with serological analyses.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
• /
• 2002.04a
• /
• pp.41-47
• /
• 2002

감 과실(Diospyros kaki folium)은 아열대로부터 온대에 이르는 넓은 지역에서 재배되고 우리나라에서는 고래로부터 중요한 과실의 하나이다. 감은 예로부터 화상, 동상, 해독 및 지혈 등의 치료에 널리 이용되어져 왔으며 특히 곶감꼭지는 시체(枾滯)라 하여 달여서 먹으면 딸꾹질을 멎게 하는데 특효가 있다고 알려져 있다. $\ulcorner$본초비효$\lrcorner$ 에서는 생감을 깍아 말린 곶감은 숙혈을 없애고, 폐열, 혈토, 구역질, 장풍과 치질을 다스리는데 쓰인다고 하였다. 또한 감은 비타민 C의 함량이 많아 감을 먹으면 감기 예방에 좋다고 알려져 왔으며 주로 생식용으로 이용되어져 왔으나 최근 감을 이용한 다양한 가공제품 및 새로운 기능성 식품의 개발을 위한 연구가 활발히 이루어지고 있다. 감의 국내 총 생산량의 약60% 이상이 영남 지방에서 집중되어 재배 생산되고 잇으며 감과실의 비중은 다른 어느 지방보다 크다고 하겠다. 감은 단감과 떫은감이 있는데 단감은 주로 생과로 이용되고 있으며 떫은감은 떫은 맛을 가지기 때문에 생과로서 이용하는데 어려움이 있다. 상주는 백미, 누애고치, 곶감 등 희게 보이는 특산물이 유명한 삼백(三白)의 고장으로 미곡 생산량 전국 9위, 떫은감 2위, 곶감은 저눅 1위, 배는 2위, 사과 5위, 포도 4위를 점유하는 농업의 비중이 매우 높은 지역으로 농산물 시장 개방 확대와 과잉생산에 따른 가격하락의 피해를 예상된다. 종래 곶감의 위생적 문제점을 보완하고 공장 규모로 생산된, 품질이 규격화되고 유통기한이 설정된 고품질 전통 곶감의 제조 및 이에 따른 기술개발이 시급히 요구된다.idin C-1-3'-3" -3/'S _0-trigallate 즉, gallate가 붙은 호합물에서100rM의 농도에서 66%와 63%의 강한 저해효과를 나타났다. Tyrosinase 저해활성을 측정한 결과는pocyanidin C-1-3'-3" -3.'S _0-trigallate는 100rM에서 70%의 강한 저해효과를 나타냈으며,epigallocatechin-(4$\beta$$\longrightarrow$8)-epigallo-catechin-(4$\beta$$\longrightarrow$8)-catechin는 51%의 저해효과를 나타내었다. 산업적응용을 위해 분획한 폴리페놀군은 미백효과 검증실험인 tyrosinase 저해율 측정평가에서 폴리페놀 함량이 가장 높은 Fraction 111의 경우 Sooppm에서 74.2%의 높은 저해율을 나타내었다. 항산화력 실험에서는500pw1이상에서 강한 활성능을 보인 SOD 유사활성능을 제외한 나머지 DPPH와 xanthine oxidase 저해효과에서는 Fraction II와III 모두가50ppm이상에서 80% 이상의 높은 유리라디칼 소거능력을 나타내었다. 그리고 각 Fraction별 항균력 측정 결과 Fraction 르와 111이 우수하게 나타났고 항균활성은 그람음성균보다 그람양성균에서 효과적이었으며, 농도별 항균력시험 결과 농도가 증가할수록 비례하여 저해율도 증가함을 알 수 있었다. 첨가농도를 달리하여 미생물의 생육도를 측정한 결과, fraction II磎꼭\ulcorner경우 그람양성균에 대해 500 ppm 이상에서 뚜렷한 증식억제효과를 나타내었다.

• Journal of the Korean Society for Railway
• /
• v.18 no.3
• /
• pp.252-260
• /
• 2015

Ballasted track on an asphalt roadbed can be beneficial for its various effects such as (i) decreasing of roadbed thickness by dispersing train load; (ii) prevention of both strength reduction and weakening in roadbed system by preventing rainwater penetration; and (iii) reducing maintenance cost by preventing roadbed mud-pumping and frostbite. With these beneficial effects, ballasted track on asphalt roadbed has been widely used in Europe and Japan, and relevant research for applying such ballasted track on asphalt roadbed systems in Korea is ongoing. In this study, full-scale static and dynamic train load tests were performed to compare the performance of ballasted track on asphalt roadbed and ballasted track. The optimum thickness levels of asphalt and reinforced roadbeds, corresponding to the design criteria for reinforced roadbed of high-speed railway, was estimated using the FEM program ABAQUS. Test results show that the earth pressure on reinforced roadbed of ballasted track on the asphalt roadbed was relatively low compared with that of simple ballasted track. The elastic and plastic displacements of simple ballasted track on the asphalt roadbed were also lower than those of ballasted track. These test results may indicate that the use of ballasted track on asphalt roadbed is an advantageous system in view of long-term maintenance.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.30 no.2
• /
• pp.159-168
• /
• 2010

This study was carried out to investigate the effects of by-product mixing silage feeding on the eating and ruminating behavior of fattening Hanwoo steer. A total of 12 Hanwoo steers (21 months old) were divided into three feeding groups and assigned to 3 dietary treatments: control (C: concentrate + ad libitum feeding of rice straw), and by-product mixing silage groups (T1: concentrate + 1 kg restricted feeding of by-product mixing silage + ad libitum feeding of rice straw, T2: concentrate + ad libitum feeding of by-product mixing silage). Eating behaviors were observed for 48 hours. Total feed intake was high in the order of T1 > C > T2, but not significantly different among the treatments. The eating and chewing time were significantly higher in C than by-product mixing silage treatments (P<0.05). Ruminating and resting time were not significantly different among the treatments. Number of bolus, number of total chews and number of chews per bolus were not significantly different among the treatments. But ruminating time per bolus and FVI (feed value index) were significantly higher in C than T1 and T2 (p<0,01, 0.05). Bolus per minute was the highest in T1 (p<0.01). Number of drinking was significantly higher in T2 than C and T1 (p<0.05), but defecating and urinating were not significantly difference among the treatments. Eating rate was the highest in T2 (p<0.05), but ruminating and chewing efficiency were not significantly difference among the treatments. Consequently, there was no big difference on eating behavior when feed by-product silage comparing with rice straw. Therefore, it is thought that by-product mixing silage could be the alternative for the rice straw.

• Journal of Sericultural and Entomological Science
• /
• v.23 no.2
• /
• pp.11-36
• /
• 1982

Forty-nine plant species as additives to silkworm artificial diet and 5 species as cellulose sources for artificial diet were screened for their economic values as feed-resources for the silkworm. Feeding response to artificial diet was tested on 82 silkworm strains. The effect of rearing conditions on feeding response and enzyme activities in the silkworm was investigated. The results were summarized as follows. 1. Seven species out of 49, Vigna sinensis ENDL, Ipomoea vatatas Lamarck, Cyperus anuricus Var. Laxus, Alnus japonica Stendel, Trifolium repens L, Prunus serrulata Lindley. Var, Glycine max L increased feeding response, compared with the basic formula of artificial diet. 2. The economic values of Vigna sinensis ENDL, Ipomoea vatatas Lamarck, Cyperus anuricus Var. Laxus, Ainus japonica Stendel, Cassia tera L, Erigeron canedensis L as feed-resources for artificiale diet were recognized, through feeding experiment during the entire larval stage. 3. Mulberry cellulose showed the best results in rearing and cocoon characteristics. 4. The extent of feeding response varied according to strains and varieties. Varieties in japanese strains showed higher feeding response than those in chinese and european varieties, with considerable variations among a varieties in strains. 5. The begining of 4th instar seems to be a proper time to convert from mulberry to artificial diet, or artificial diet to mulberry, however the middle of 3rd instar seems acceptable. 6. The optimum temperature for artificial diet rearing is 30$^{\circ}C$ during the period of 1st-3rd instar and 28$^{\circ}C$ for 4th-5th instar. 7. Electrophoretic isozyme patterns of esterase and acid phosphatase on agarose gel, as affected by strain. rearing temperature and feed-resources, were observed as follow. (1) Isozyme patterns of mid-gut esterase varied, depending on instar. One or two more isozyme bands were observed in the larvae than feed on the mulberry fed for the artificial diet. (2) A strain, chinese-15 with a higher feeding response, had 1∼2 more bands than chinese-60 with a lower feeding response. (3) Five bands of mid-gut esterase in 3rd and 4th instar larvae reared at 28$^{\circ}C$. and 4 for 3rd instar and 6∼7 for 4th instar larvae at 35$^{\circ}C$ were observed. (4) No similar esterase bands could be found among mid-gut, blood and silkgland. There are five esterase bands in the midgut, one in blood and three in silkgland. (5) There was rather small digerence in acid phosphatase types of mid-gut and blood according to varieties and rearing temperature. No active band was shown in silkgland. In midgut, there was one acid phosphatase band at 3rd instar, two at 4th instar and three at 5th instar. In blood, one active band at 3rd or 4th instar and three bands at 5th inster wire detected.