• Journal of The Korean Society of Grassland and Forage Science
• /
• v.30 no.4
• /
• pp.309-316
• /
• 2010

The performance of grass filter strips (GFS) in reducing $PO_4$-P concentrations and soil loss from the forage cropland was tested in an experiment on the 10% slope in Grassland and Forages Division, National Institute of Animal Science, Rural Development Administration (RDA) from October 2007 to September 2009. Forage cropland with rye-corn double cropping system receiving inorganic fertilizer or livestock manure (LM) were compared in a natural condition. The plots were hydrologically isolated in a randomized block layout of 3 treatments $\times$ 2 factors $\times$ 3 replicates. Main plots consisted of the length of GFS, such as $25\;m^2$ ($5{\times}5\;m$), $50m^2$ ($5{\times}10\;m$), $75m^2$ ($5{\times}15\;m$). Sub plots consisted of the type of LM, such as chemical fertilizer (CF), cattle manure (CM) and swine manure (SM). Concentrations of $PO_4$-P in surface runoff water were reduced as the length of GFS increased. Especially, GFS with 10 m and 15 m reduced $PO_4$-P concentrations significantly compared to that with 0 m (p<0.05). However, there was not significant different between $PO_4$-P concentrations of GFS with 10m and that of GFS with 15 m. Moreover, Soil loss in surface runoff water were reduced as the length of GFS increased. GFS with 15 m reduced soil loss significantly compared to that with 5 m and 10 m (p<0.05). The results from this study suggest GFS improve the removal and trapping $PO_4$-P and soil loss from forage cropland.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.30 no.3
• /
• pp.247-256
• /
• 2010

This experiment was carried out to investigate the effect of seeding rate of newly developed Italian ryegrass varieties, "Kogreen" and "Hwasan 101", on those seed production in Cheonan for three years (2005 to 2007). Two Italian ryegrass varieties were seeded at experimental fields of Grassland and Forage Division, National Institute of Animal Science on late September, and harvested at seed shattering stage. The experiment was arranged in randomized complete block design with three replications by each variety. The treatments was consisted of five seeding rates (5, 10, 20, 30, 40 kg/ha). The average heading date of "Kogreen" was 9 May and "Hwasan 101" was 25 May. The harvesting date of "Kogreen" was on 16 June when the rainy season should not set in. In the case of "Hwasan 101", the harvesting date of seed production was 3 July, because of rainy season. The number of ear per square meter, ear length, spikelet number, seed yield per ha and ripening rate of "Hwasan 101" were 471, 28.5 cm, 24.8, 1,631 kg and 71%, respectively. and those of "Kogreen" were 633, 24.0 cm, 20.8, 2,676 kg and 82.1%, respectively. The shattering property rate of "Hwasan 101" 40.3% was higher than that of "Kogreen" 2.6%. The germination rate of harvested "Hwasan 101" seed was 81.8% and that of "Kogreen" was 79.4%, respectively. In conclusion, the optimum seeding rate of Italian ryegrass for seed production are recommended 20kg/ha in both "Hwasan 101" and "Kogreen".

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.27 no.4
• /
• pp.249-256
• /
• 2007

This experiment was conducted to compare the agronomic characteristics and productivity in introduced hairy vetch cultivars and developed new Korean Hairy vetch cultivars in two areas of the experimental field of Grassland and Forage Crops Division, National Institute of Animal Science from 2005 to 2006. The experiment was arranged in randomized complete block design with three replications. A total of 11 hairy vetch cultivars used in this study including 9 introduced cultivars (Penn-02, Sander, Latigo, Welta, Ostsaat, VV4712, Minnie, Barlosa and Capello) and 2 Korean cultivars (Cold green and Cheong pa). The early flowering varieties of Minnie, Barlosa, Capello and Cold green were grown as early maturity cultivars, while the late flowering varieties of Penn-02, Sander, Latigo, Welta, Ostsaat, VV4712 and Cheong pa were grown as medium and late maturity. The winter hardiness of hairy vetch was good except for Minnie, Barlosa and Capello of early maturity cultivars. In this study, dry matter yield of VV4712 was the highest of 11 hairy vetch cultivars. And dry matter yield of medium and late maturity vetch increased in the middle region while that of early maturity increased in the south. The new Korean cultivar, Cheong pa, as a medium and late maturity hairy vetch was not bad compared to introduced cultivars and Cold green as an early maturity hairy vetch was an excellent cultivar compared to introduced cultivars in both regions. Latigo in NDF (neutral detergent fiber) and Welta in ADF (acid detergent fiber) were lower than other cultivars, while Sander in IVDMD (in vitro dry matter digestibility) and CP (crude protein) content were higher than other cultivars. The results of this experiment indicated that the productivity of hairy vetch cultivars was highest in VV4712, and Cheong pa and Cold green of new Korean cultivar were the promising cultivars of hairy vetch in Korea.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.37 no.4
• /
• pp.277-282
• /
• 2017

This study was conducted to evaluate on agronomic characteristics, forage quality and dry matter (DM) yields of mugwort (Artemisia princeps Pamp.) collected different region at Seongju in Kyeongbuk from 2014 to 2015. The experiment was arranged in randomized complete block design with three replications. Mugwort was planted on $17^{th}$ March, 2014 and harvested on $13^{th}$ September, 2014 and on $25^{th}$ May and $9^{th}$ September, 2015. DM yields of Dalsung(1), Seongju B.(1), Dalsung(2) and Sajuarissuk were 17.3, 16.8, 16.7 and $16.7(MT\;ha^{-1})$, respectively and the DM yields of those were higher (p<0.05) than the other mugworts in 2014. In 2015, DM yields of Dalsung(1), Dalsung(2), Seongju B.(1), and Sajuarissuk were 19.5, 19.3, 18.4 and $18.4(MT\;ha^{-1})$, respectively and DM yields of those were higher (p<0.05) than the others. DDM(digestable dry matter) content of mugworts was a range of 56.4 to 60.8% and that of Sajabalssuk, 60.8% was the highest. Seongju B.(1) 58.8% was higher than Seongju B.(2) 56.4% but there were no difference among the Dalsung(1) 58.4%, Dalsung(2) 58.1%, Sajuarissuk 57.7% and Yeongcheon. The result of this study indicated that Dalsung(1), Dalsung(2), Sajuarissuk and Seongju B.(1) would be recommendable for forage production.

• Horticultural Science & Technology
• /
• v.34 no.1
• /
• pp.195-205
• /
• 2016

Sugar beet cyst nematode, Heterodera schachtii, causes serious economic losses worldwide in Brassicaceae crops. In 2011, this nematode was first found in highland vegetable cultivation areas in Korea, and thereafter spread to the surrounding healthy Chinese cabbage fields. However, little has been documented on the biological and ecological characteristics of the sugar beet nematode in highland vegetable cultivation areas. In this study the dispersal of the sugar beet cyst nematode was examined, focusing on spreading through soil and/or water infested with the nematode. When farmers with work boots trampled on Chinese cabbage fields for 10 minutes, the number of cysts recovered from the soil attached to the working differed depending on the research sites. Under irrigation conditions of 2, 4, and 8 liters of water per $m^2$, the amounts of soils attached on the bottom of the work boots and the number of healthy cysts in the soils increased significantly with the increase in soil moisture, although the total number of cysts, eggs, and juveniles did not increase significantly. After driving on the farm road adjacent to cabbage fields infested with the sugar beet cyst nematode, cysts were also recovered from the soil attached to the vehicle's tires, suggesting that the sugar beet cyst nematode can spread to new fields through soil carried by vehicles and by farmers. An excavator and a motor truck could deliver 41 kg and 224 g, respectively, of soil on the shovel shoes and the wheels to other locations during the Chinese cabbage harvest, suggesting that farming equipment and transportation vehicles may be vital means by which the cyst nematode spreads to non-infested fields in the highland area of Korea. Runoff water also contained cysts, whose amounts increased after water irrigation onto the ridges to simulate rainy conditions, with no significant difference in the number of cysts with increasing amounts of irrigation water. All of these results confirmed that the sugar beet cyst nematode spreads through soil attached to work boots, harvesting tools, and transportation vehicles, especially during the harvest time, and through runoff water on rainy days. These observations suggest that personal sanitization and cleaning of working tools and vehicles are one of the most important means to prevent the dispersal of the sugar beet cyst nematode in fields.

• Bulletin of the Society of Naval Architects of Korea
• /
• v.27 no.3
• /
• pp.131-136
• /
• 1990

여러해 전부터 선박의 생산실적이나 생산성 관련 자료를 기록하고 보완하는 작업을 꾸준히 개선토록 노력해온 결과중 중요한 것 하나는, 선박의 여러 가지 설계 검토과정에서 충분히 활용할 수 있는 함축성 있고 믿을만한 형태의 생산정보를 제공해줄 수 있게 되었다는 것이라고 말 할 수 있겠다. 이러한 자료들은 생산계획상 각 단계(stage)에서의 작업량, 예상재료비와 인건비의 산출등이 포함될 수 있으며, 선박이나 해상구조물의 전반적인 설계방법론(design methodology)을 개선코자 한다면 ''생산지향적 설계(Design for Production)''의 근간이 되는 선박건조전략(build strategy), 구매정책(purchasing policy)과 생산기술(production technology)에 대한 폭넓은 지식이 한데 어우러져야 한다. 최근에는 CIMS의 일부분에서 보는 바와 같은 경영관리, 설계 및 생산지원 시스템의 도입으로 이와 같은 설계 프로세스의 추진을 가능케하고 있다. 이와 병행하여 설계를 지원하기 위한 전산기술, 특히 대화형 화상처리기술(interactive graphics)의 발달은 설계자가 선박의 형상이나 구조 배치를 여러 가지로 변화시켜 가면서 눈으로 즉시 확인할 수 있도록 설계자의 능력을 배가시키는데 크게 기여하고 있다. 여러 가지의 설계안(alternative design arrangement)을 신속히 만들어내고 이를 즉시 검토 평가할 수 있는 능력을 초기설계 단계에서 가질 수 있다면 이는 분명히 큰 장점일 것이며, 더구나 설계초기 단계에 생산관련인자를 설계에서 고려할 수 있다면 이는 더욱 두드러진 발전일 것이다. 생산공법과 관련생산 비용을 정확히 반영한 각 가지의 설계안을 짧은 시간내에 검토하고 생산소요 비용을 산출하여 비교함으로써, 수주계약단계에서 실제적인 생산공법과 신뢰성있는 생산실적자료를 기준으로 하여 총 건조비(total production cost)를 최소로 하는 최적의 설계를 선택할 수 있도록 해 줄 것이다. 이제 이와 같은 새로운 설계도구(design tool)를 제공해 주므로써 초기설계에 각종 생산관련 정보나 지식 및 실적자료가 반영가능토록 발전되었다. 본 논문은 영국의 뉴카슬대학교(Univ. of Newcastle upon Type)에서 위에 언급한 특징들을 반영하여 새로운 선박구조 설계 방법을 개발한 연구결과를 보여주고 있다. 본 선계연구는 5단계로 구분되는데; (1) 컴퓨터 그라픽스를 이용하고 생산정보 데이타베이스와 연결시켜 구조형상(geometry)을 정의하고 구조부재 칫수(scantling) 계산/결정 (2) 블럭 분할(block division) 및 강재 배치(panel arrangement)의 확정을 위해 생산기술 및 건조방식에 대한 정보 제공 (3) 상기 (1) 및 (2)를 활용하여 아래 각 생산 단계에서의 생산작업 분석(work content assessment) a) 생산 준비 단계(Preparation) b) 가공 조립 단계(Fabrication/Assembly) c) 탑재 단계(Erection) (4) 각각의 설계(안)에 대하여 재료비(material cost), 인건비(labour cost) 및 오버헤드 비용(overhead cost)을 산출키 위한 조선소의 생산시설 및 각종 품셈 정보 (5) 총 건조 비용(total production cost)을 산출하여 각각의 설계안을 비교 검토. 본 설계 방식을 산적화물선(Bulk Carrier) 설계에 적용하여 구조배치(structural geometry), 표준화의 정도(levels of standardisation), 구조생산공법(structural topology) 등의 변화에 따른 설계 결과의 민감도를 분석(sensitivity studies)하였다. 전산장비는 설계자의 대화형 접근을 용이하도록 하기 위해 VAX의 화상 처리장치를 이용하여 각 설계안에 대한 구조형상과 작업분석, 건조비 현황 등을 제시할 수 있도록 하였다. 결론적으로 본 연구는 설계초기 단계에서 상세한 건조비 모델(detailed production cost model)을 대화형 화상 처리방법에 접합시켜 이를 이용하여 여러가지 설계안의 도출과 비교검토를 신속히 처리할 수 있도록 함은 물론, 각종 생산 실적정보를 초기설계에 반영하는 최초의 시도라고 믿으며, 생산지향적(Design for Production) 최적설계분야의 발전에 많은 도움이 되기를 기대해 마지 않는다. 참고로 본 시스템의 설계 적용결과를 부록에 요약 소개하며, 상세한 내용은 참고문헌 [4] 또는 [7]을 참조 요망한다.

• Korean Journal of Heritage: History & Science
• /
• v.43 no.4
• /
• pp.24-55
• /
• 2010

Jangmyeongdeung Lantern (貞陵長明燈) refers to the stone lantern placed in front of the royal tomb. It serves both symbolic and decorative purposes; symbolic because it is supposed to guard and illuminate the buried, and decorative because it is a work of sculpture that adorns the entire graveyard. The Jangmyeongdeung of Jeongneung was the earliest stone lantern to be produced during the Joseon period. Its square shape is unique among those from the early to mid-Joseon period. The three major parts of Jangmyeongdeung - the stand, the lantern, and the roof-shaped cover parts - are square in shape, differing from the octagonal shaped Jangmyeongdeung. The stand consists of three single stone blocks, the Hadaeseok(下臺石), Ganjuseok(竿柱石), and Sangdaeseok(上臺石). The Hwasaseok(火舍石), or the lantern part, is also a single stone block. Jangmyeongdeung of Jeongneung succeeds the style of those of Hyeon-neung and Jeongneung(玄正陵) of the Goryeo period and is of a better artistic quality. As the first Jangmyeongdeung lantern, it is a refined work of art that marks the foundation of the Joseon Kingdom. This paper tries to ascertain the stylistic origin of the square-shaped Jangmyeongdeung of Jeongneung and compare it with those of Buddhist temples. Consequently, similarities were found among the stone lanterns of Zen priests 'Jigong'(指空) and 'Nawong'(懶翁) in the Hweamsa Temple(檜巖寺) site from the late Goryeo period, those of Zen priest 'Muhak'(無學) of the Hweamsa Temple site, and those of national priest 'Bogak'(普覺) of Cheongnyongsa Temple(靑龍寺) from the early Joseon period. Primarily, this is because the three components(the stand, the lantern part, and the roof-shaped cover) are essentially square-shaped. Second, as the Ganjuseok(one of the components of the stand) became shorter, the stand took a more stable form. Third, the Hwasaseok(the lantern part) consists of two stone blocks joined together. Fourth, the roof-shaped cover is also in square in shape. Similarly, the Jangmyeongdeung of Jeongneung contains Buddhist elements as well. The three-bead pattern that decorates the Ganjuseok stand is an example. The three-bead pattern is one of the symbolic elements related to Tantric Buddhism. It is found on the diadems worn by Bodhisattvas from the Goryeo and early Joseon periods. The Jangmyeongdeung of Jeongneung in early Joseon directly influenced the production of the square-shaped stone lanterns used to decorate the tombs during the Joseon period. After the latter half of the 15th century, however, the octagonal-shaped Jangmyeongdeung style began to prevail. The Jangmyeongdeung of Jeongneung reflects the succession of the tradition of royal tombs from Goryeo to Joseon, the introduction of square-shaped stone lanterns to Buddhist temples, and the influence of the Buddhist philosophy of the time. It is a living testimony to various elements of each time and corresponding cultural trends.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.44 no.2
• /
• pp.64-70
• /
• 2024

The experiment was conducted to determine the changes in seed productivity of Italian ryegrass (Lolium multiflorum Lam.) according to nitrogen fertilization levels in the southern region of Korea. Italian ryegrass (IRG) variety 'Green Call' was sown in the fall of 2021 in Jinju, Gyeongsangnam-do. The experiment consisted of three nitrogen fertilizer levels (100, 120, and 140 N kg/ha) with three replications using a randomized complete block design. Harvesting was done approximately 30 days after heading on May 18th. There was no difference in heading date among treatments, which occurred on April 18th. The longest IRG was observed in the 140 N kg/ha treatment, but there was no significant difference. No significant differences were observed in lodging, disease resistance, and cold tolerance among treatments, but lodging was severe in all treatments. The length of the spike averaged 44.95 cm, with no difference among treatments, and the number of seeds per spike was highest in the 120 N kg/ha treatment. Seed yield increased with increasing nitrogen fertilizer levels, averaging 3,707 kg/ha (as-fed basis). DM content of seed and straw averaged 76.95% and 62.19%, respectively, with no significant differences among treatments. The remaining straw after harvesting averaged 6,525 kg/ha on a dry matter basis, with the highest value observed in the 140 N kg/ha treatment. Overall, considering the results, the optimal nitrogen fertilizer application rate for seed production of Italian ryegrass in the southern region when sown in autumn was found to be 120 N kg/ha.

• Korean Journal of Mineralogy and Petrology
• /
• v.33 no.3
• /
• pp.273-291
• /
• 2020

The strength characteristics of the three orthogonal splitting planes, known as rift, grain and hardway planes in granite quarries, were examined. R, G and H specimens were obtained from the block samples of Jurassic granites in Geochang and Hapcheon areas. The directions of the long axes of these three specimens are perpendicular to each of the three planes. First, The chart, showing the scaling characteristics of three graphs related to the uniaxial compressive strengths of R, G and H specimens, were made. The graphs for the three specimens, along with the increase of strength, are arranged in the order of H < G < R. The angles of inclination of the graphs for the three specimens, suggesting the degree of uniformity of the texture within the specimen, were compared. The above angles for H specimens(θ^H, 24.0°~37.3°) are the lowest among the three specimens. Second, the scaling characteristics related to the three graphs of RG, GH and RH specimens, representing a combination of the mean compressive strengths of the two specimens, were derived. These three graphs, taking the various N-shaped forms, are arranged in the order of GH < RH < RG. Third, the correlation chart between the strength difference(Δσ_t) and the angle of inclination(θ) was made. The above two parameters show the correlation of the exponential function with an exponent(λ) of -0.003. In both granites, the angle of inclination(θ^RH) of the RH-graph is the lowest. Fourth, the six types of charts, showing the correlations among the three kinds of compressive strengths for the three specimens and the five parameters for the two sets of microcracks aligned parallel to the compressive load applied to each specimen, were made. From these charts for Geochang and Hapcheon granites, the mean value(0.877) of the correlation coefficients(R²) for total density(Lt), along with the frequency(N, 0.872) and density(ρ, 0.874), is the highest. In addition, the mean values(0.829) of correlation coefficients associated with the mean compressive strengths are more higher than the minimum(0.768) and maximum(0.804) compression strengths of three specimens. Fifth, the distributional characteristics of the Brazilian tensile strengths measured in directions parallel to the above two sets of microcracks in the three specimens from Geochang granite were derived. From the related chart, the three graphs for these tensile strengths corresponding to the R, G and H specimens show an order of H(R1+G1) < G(R2+H1) < R(R1+G1). The order of arrangement of the three graphs for the tensile strengths and that for the compressive strengths are mutually consistent. Therefore, the compressive strengths of the three specimens are proportional to the three types of tensile strengths. Sixth, the values of correlation coefficients, among the three tensile strengths corresponding to each cumulative number(N=1~10) from the above three graphs and the five parameters corresponding to each graph, were derived. The mean values of correlation coefficients for each parameter from the 10 correlation charts increase in the order of density(0.763) < total length(0.817) < frequency(0.839) < mean length(Lm, 0.901) ≤ median length(Lmed, 0.903). Seventh, the correlation charts among the compressive strengths and tensile strengths for the three specimens were made. The above correlation charts were divided into nine types based on the three kinds of compressive strengths and the five groups(A~E) of tensile strengths. From the related charts, as the tensile strength increases with the mean and maximum compressive strengths excluding the minimum compressive strength, the value of correlation coefficient increases rapidly.