• Title/Summary/Keyword: spring flush

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Effect of Grass Silage Supplementation on Performance in Lactating Cows Grazing on Pasture

  • Sung, K.I.;Okubo, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.10
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    • pp.1409-1418
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    • 2001
  • Two trials were carried out during two different grazing seasons to evaluate effect of grass silage supplementation, when amount of pasture is limited on dry matter intake (DMI), milk production, and gross energetic efficiency (GEE) of grazed lactating cows on a high forage-based diet. Fifty-one Holstein cows were randomly assigned to one of two dietary treatments: high pasture group or high silage group. In the spring flush, pasture and silage DMI, milk yield, milk fat percentage, and GEE were not different between the dietary groups. After the spring flush, pasture and silage DMI were higher for the high silage group than for the high pasture group. After the spring flush, although these were the higher total DMI of the high silage group than the high pasture group, milk yield was significantly (p<0.05) higher for the high pasture group than the high silage group. Milk fat percentage tended to be higher for the high silage group than the high pasture group. The GEE was significantly (p<0.05) higher for the high pasture group than the high silage group during after the spring flush. This study indicated that supplementation of grass silage, especially after the spring flush, can have a significant effect of increasing of forage intake and maintenance of the milk fat percentage; but not increase milk yield and GEE.

목초생육이 왕성한 시기의 윤환방목에 의한 초지이용

  • 성경일;최아랑;정종원;김병완
    • Proceedings of the Korean Society of Grassland Science Conference
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    • 1999.06a
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    • pp.87.2-88
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    • 1999
  • 목초생육이 왕성한 시기(spring flush기)에 있어서 방목용 초지의 지나친 성장은 제상이나 불식초 증가로 방목초의 섭취량이 저하하므로, 이 시기에 적절한 초지상태를 유지하여 방목초나 섭취량의 저하를 억제해야 한다. 본 연구에서는 spring flush기에 있어서 윤환방목에 의한 초지의 이용에 대하여 검토하였다.(중략)

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Breeding and Cultural Characteristics of Newly Bred Lentinula edodes Strain 'Sanjanghyang' (신품종 표고버섯 '산장향'의 교배 육성 및 재배 특성)

  • Park, Youngae;Jang, Yeongseon;Ryoo, Rhim;Lee, Bonghun;Ka, Kang-Hyeon
    • The Korean Journal of Mycology
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    • v.47 no.2
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    • pp.143-152
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    • 2019
  • A new cultivar 'Sanjanghyang' was bred from monokaryotic strains of 'Sanbaekhyang' and 'Jangan 1ho'. Pileus was flat, round, and reddish brown. The diameters of the pilei and stipe length of the fruiting bodies were 67.1 mm and 16.9 mm, respectively. The scales were white or slightly brown and distributed evenly. The gill density was sparse and showed a rippled texture. The stipe was cream in color and the fluff was medium. 'Sanjanghyang' had a short cultivation period and fruiting bodies occurred sporadically. Temperature for fruiting body formation was a medium, between 15 to $19^{\circ}C$. 'Sanjanghyang' was different from 'Sanbaekhyang' with regard to its pileus diameter (67.1 mm) and autumn and spring fruiting body production period. 'Sanbaekhyang' had pileus diameter of 74.7 mm, and fruiting body formation occurred in spring and autumn. The rate of fruiting body formation was 89% (first flush), 4% (second flush), and 7% (third flush).

A Simplified Steel Beam-To-Column Connection Modelling Approach and Influence of Connection Ductility on Frame Behaviour in Fire

  • Shi, Ruoxi;Huang, Shan-Shan;Davison, Buick
    • International Journal of High-Rise Buildings
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    • v.7 no.4
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    • pp.343-362
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    • 2018
  • A simplified spring connection modelling approach for steel flush endplate beam-to-column connections in fire has been developed to enable realistic behaviour of connections to be incorporated into full-scale frame analyses at elevated temperature. Due to its simplicity and reliability, the proposed approach permits full-scale high-temperature frame analysis to be conducted without high computational cost. The proposed simplified spring connection modelling approach has been used to investigate the influence of connection ductility (both axial and rotational) on frame behaviour in fire. 2D steel and 3D composite frames with a range of beam spans were modelled to aid the understanding of the differences in frame response in fire where the beam-to-column connections have different axial and rotational ductility assumptions. The modelling results highlight that adopting the conventional rigid or pinned connection assumptions does not permit the axial forces acting on the connections to be accurately predicted, since the axial ductility of the connection is completely neglected when the rotational ductility is either fully restrained or free. By accounting for realistic axial and rotational ductilities of beam-to-column connections, the frame response in fire can be predicted more accurately, which is advantageous in performance-based structural fire engineering design.

Suppressive Effects of Bio-Sulfur on Citrus Scab (바이오 황을 이용한 감귤 더뎅이병 발병 억제 효과)

  • Oh, Myung-Hyup;Hyun, Jae-Wook;Park, Won-Pyo;Hyun, Hae-Nam
    • Korean Journal of Organic Agriculture
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    • v.28 no.2
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    • pp.223-233
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    • 2020
  • The aim of the present study was to investigate the suppressive effects of the bio-sulfur used by eco-friendly farms on the outbreak of citrus scab. To evaluate the inhibiting effect of bio-sulfur on citrus scab germ tube growth, the citrus scab pathogen Elsinoe fawcettiiwas cultured in PDB and agar media, and germ tube growth was observed after bio-sulfur treatment. At both 40 and 88 h after inoculation, germ tube formation was inhibited by 500-, 1000-, and 2000-fold diluted bio-sulfur, and at dilutions above 4000-fold, germ tube formation was observed, although growth was still inhibited, when compared to untreated cultures. Meanwhile, the occurrence of citrus scab on spring-flush leaves in the field was 40.3% in the untreated control and 5.3, 10.3, 12.3, 15.3, and 24.0% when treated with imibenconazole, 2-4 and 6-6 lime-Bordeaux mixtures, which are also used by eco-friendly farms, 500-fold diluted bio-sulfur, lime sulfur, and 1000-fold diluted bio-sulfur, respectively. The occurrence of citrus scab on citrus fruit was 79.3% in the untreated control and 4.0, 33.8, 42.0, 43.3, 44.8, and 78.0% when treated with imibenconazole, 2-4 lime-Bordeaux mixture, 6-6 lime-Bordeaux mixture, 500-fold diluted bio-sulfur, lime sulfur, and 1000-fold diluted bio-sulfur, respectively. Because citrus scab can infect citrus leaves as early as May, as the spring flush begins, preventative control should be implemented by mid- to late-April, thereby increase disease control and reducing both labor and farming costs.

Dynamic EMCs and Optimum Treatment Criteria for Stormwater Runoff of a Railway Station (철로 역사 건설에 따른 강우 유출수내 비점오염물질의 동적 EMCs 및 처리방안 연구)

  • Lim Kyeong-Ho;Kim Kee-Dong;Lee Byung-Sik;Kim Lee-Hyung
    • Journal of the Korean Society for Railway
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    • v.8 no.4
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    • pp.308-313
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    • 2005
  • In order to successfully propel the stormwater management program, administration plan of stormwater management is enacted in Spring, 2005. Hereafter, in a newly developing area such as a railway station, the best management practices should be established to control the nonpoint pollutant. Construction of a railway station means the increasing of imperviousness rate and lots of nonpoint pollutant emissions during rainfall. Therefore this research was performed to determine the pollutant EMC and to suggest the possible best management practice for treating nonpoint pollutants from a railway station. The $95\%$ confidence intervals of pollutant EMC were ranged to 69.4-115.2mg/L for TSS, 132.7-190.4mg/L for COD, 5.4-15.1ug/L for Oil & Grease, 4.9-12.4mg/L for TKN and 568.4-620.1ug/L for TP. The first flush criteria was ranged to 5-10mm accumulated rainfall using dynamic EMCs, Also laboratory reactor testing was performed. It shows that Zeolite media is useful for removing the washed-off pollutants from a railway station, especially for metal ions.

Survey of the Secondary Effluents from Municipal Wastewater Treatment Plants in Korea (우리나라 하수처리장 방류수 수질현황 및 특성)

  • Kim, Youngchul;An, Ik-Sung;Kang, Min-Gi
    • Journal of Korean Society on Water Environment
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    • v.21 no.2
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    • pp.158-168
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    • 2005
  • In this study, the discharging effluents from have been 9 municipal wastewater treatment plants surveyed for 1 year-period. Statistics including probability distribution, cumulative occurrence concentration and other statistical parameters were presented. In addition, treatment performance and its stability were also discussed. Most of the plants, have an operational problem of high soluble organic content in the secondary effluent which may be associated with the integrated treatment of human and livestock manures. Nitrogen concentration in the effluents were usually higher during the period of summer and winter. It was found that this is mainly due to lack of the proper C/N ratio during the summer, or/and the effects of low temperature and less dilution by dry weather during the winter. Phosphorus concentration is sharply increased in June. Discussion with plant operators told that it is due to the dissolution of phosphate from the sludge accumulated in the primary settling tanks from the early spring to june. During this period, usually, sludge treatment line is highly overloaded with flush-outs of the sediments also stored in the bottom of combined sewer due to the low flow during winter season. Most of the plants can meet new effluent discharge limits of the nitrogen and phosphorus, and total coliform without further treatment.

Dynamic increase factor for progressive collapse analysis of semi-rigid steel frames

  • Zhu, Yan Fei;Chen, Chang Hong;Yao, Yao;Keer, Leon M.;Huang, Ying
    • Steel and Composite Structures
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    • v.28 no.2
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    • pp.209-221
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    • 2018
  • An empirical and efficient method is presented for calculating the dynamic increase factor to amplify the applied loads on the affected bays of a steel frame structure with semi-rigid connections. The nonlinear static alternate path analysis is used to evaluate the dynamic responses. First, the polynomial models of the extended end plate and the top and seat connection are modified, and the proposed polynomial model of the flush end plate connection shows good agreement as compared with experimental results. Next, a beam model with nonlinear spring elements and plastic hinges is utilized to incorporate the combined effect of connection flexibility and material nonlinearity. A new step-by-step analysis procedure is established to obtain quickly the dynamic increase factor based on a combination of the pushdown analysis and nonlinear dynamic analysis. Finally, the modified dynamic increase factor equation, defined as a function of the maximum ratio value of energy demand to energy capacity of an affected beam, is derived by curve fitting data points generated by the different analysis cases with different column removal scenarios and five types of semi-rigid connections.

Optimum Capacity of Retention Basin for Treating Nonpoint Pollutants and Its Removal Efficiency in Industrial Complex Areas (산업단지내 비점오염물질 처리를 위한 적정 저류조 용량 산정 및 처리효율)

  • Kim, Lee-Hyung;Lee, Byung-sik;Kwon, Soo-Youl
    • Journal of Wetlands Research
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    • v.7 no.3
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    • pp.75-85
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    • 2005
  • The Construction of industrial complex areas means the increase of imperviousness rate and the increase of nonpoint pollutant emissions during a rainfall. Generally the retention basin can become the alternative for removing and controling these nonpoint pollutants. Recently Ministry of Environment are trying to change the purpose of retention basins from flooding control to nonpoint pollutant control. In order to propel the stormwater management program, administration plan of stormwater management is enacted in Spring, 2005. Hereafter, in a newly developing area, the best management practices should be established to control the nonpoint pollutant. Landuses of the research area are classified to the categories of the 1st manufacturing industry, metal industry, fiber and chemical product manufacturing industry, etc. Therefore, this research was performed to understand washed-off characteristics of stormwater and to suggest the controling method of nonpoint pollutants. The optimum capacity of the retention basin can be determined by analyzing the relationships among data of rainfall, runoff, washed-off pollutants from the areas. The rainfall analysis using the data of normal year, recent 2, 5 and 10 years shows that the 80% rainfall frequency was occurred on 10mm accumulated rainfall, but which is not considered the first flush effect. However, by considering the first flush effect, the appropriate treatment capacity of rainfall can be decreased to 4-5mm accumulated rainfall. Using the criteria, the optimum capacity of retention basin is determined to $12,000m^3$ in the research area. The washed-off nonpoint pollutant loading from the areas have beeb calculated to 435ton/yr for TSS, 238ton/yr for COD, 8,518kg/yr for TKN and 1,816kg/yr for TP. The mass of 78.3ton/yr for TSS, 20.4ton/yr for BOD, 128.6ton/yr for COD, 4.6ton/yr for TKN and 980kg/yr for TP can be reduced by constructing the retention basin. The sediment accumulation rate is also calculated by $6.53kg/m^2-hr$.

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Nitrogen Recovery and Application Method in a Satsuma Mandarins Orchard (온주밀감 과원 토양에서 질소에 대한 시비방법과 시비수준에 따른 회수율)

  • Kang, Young-Kil;U, Zang-Kual;Kang, Bong-Kyoon
    • Korean Journal of Soil Science and Fertilizer
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    • v.31 no.2
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    • pp.143-150
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    • 1998
  • In order to evaluate the nitrogen (N) balance, from the different application methods and levels of $^{15}N$ applied to a satsuma mandarin orchard soils in spring, we surface-applied N as urea at the rates of 50 (water-dissolved), 100 (solid and water-dissolved) and 150% (solid) of the recommended rate ($180kg\;ha^{-1}$) in spring (lebeled N), summer (nonlebeled N) with application ratio of 5:2:3. Fruit yield and quality were not significantly affected by any treatment. Nitrogen contents of spring flush leaves in late August were 3.0% regardless of the treatments. The N recovery by parts of tree itself was in the order of leaves, fruits, roots, stems, and the highest recovery per tree was 22.3% in the 50% recommended water-dissolved surface broadcast while there were not much differences for N recovery (11.9 to 13.6%) among the other three treatments. Total N content in top 30cm of soils was 0.47% regardless of the treatments, but N proportion and total residual N from the fertilizer applied increased with increasing N rate while the N recovery in soils decreased. For the recommended N rate, N proportion and the residual N from the fertilizer applied were greater in the water-dissolved surface broadcast than those in soils surface broadcast. The highest total (tree + soils) N recovery was 70.9% in the 50% recommended water-dissolved surface broadcast, but tended to decrease to 52.2, 46.6, and 43.2% for the recommended water-dissolved surface broadcast, 100 and 150% of the recommended solid surface broadcast, respectively.

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