• Title/Summary/Keyword: Second cut

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A study on the effects of second cut on the roughness of surfaces treated with wire-cut electric discharge machining (W-EDM) (2차 가공이 와이어 컷 방전가공면 표면조도 분포에 미치는 영향에 관한 연구)

  • Kim, Sei-hwan;Choi, Kye-kwang
    • Design & Manufacturing
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    • v.6 no.1
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    • pp.58-62
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    • 2012
  • Unlike conventional single special cut methods, W-EDM is a combination of multiple-effects. This study focuses on the effects of second cut on the roughness of surfaces treated with W-EDM. W-EDM is, to a large extent, typical unmanned-machining equipment, which represents NC machining equipment that allows long-time full automation. W-EMD is getting popular as a precise machining technology and STD11 is frequently used in press die manufacture. In this study, the former is applied to the latter to look at the effects of second cut on the roughness of surfaces treated with W-EDM.

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THE CONNECTIVITY AND THE MODIFIED SECOND MULTIPLICATIVE ZAGREB INDEX OF GRAPHS

  • DU, JIANWEI;SUN, XIAOLING
    • Journal of applied mathematics & informatics
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    • v.39 no.3_4
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    • pp.339-358
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    • 2021
  • Zagreb indices and their modified versions of a molecular graph are important descriptors which can be used to characterize the structural properties of organic molecules from different aspects. In this work, we investigate some properties of the modified second multiplicative Zagreb index of graphs with given connectivity. In particular, we obtain the maximum values of the modified second multiplicative Zagreb index with fixed number of cut edges, or cut vertices, or edge connectivity, or vertex connectivity of graphs. Furthermore, we characterize the corresponding extremal graphs.

Methane Emissions from Dry Cows Fed Grass or Legume Silage

  • Kasuya, Hirotaka;Takahashi, Junichi
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.5
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    • pp.563-566
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    • 2010
  • Using an open-circuit system, we compared the methane ($CH_4$) emission from dry cows fed first-cut Timothy silage ($1^{st}$ TY), second-cut Timothy silage ($2^{nd}$ TY), second-cut Italian ryegrass silage ($2^{nd}$ IR), third-cut Italian ryegrass silage ($3^{rd}$ IR), or second-cut red clover silage ($2^{nd}$ RC) as the sole feed. The methane emission ranged from 258.2 L $day^{-1}$ to 396.5 L $day^{-1}$. The methane emission from dry cows fed red clover silage was relatively lower than that from dry cows fed grass silage. However, the methane emission per unit digestible neutral detergent fiber (NDF) intake (dNDFI) did not differ significantly between the experimental silages. The methane emission was significantly correlated with the NDF intake and digestibility. Methane emission had a significant correlation with the quadratic function of dNDFI. The differences in the daily volume of methane emission from cows fed different forages can be explained by dNDFI.

Comparison of Dry Matter Production in Reed canarygrass Varieties (Reed canarygrass 품종의 건물 생산성 비교)

  • 이주삼;류수훈;이경은
    • Asian Journal of Turfgrass Science
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    • v.7 no.2_3
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    • pp.121-127
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    • 1993
  • This experiment was carried out to compare the varietal differences of dry matter production in rend canarygrass. The varieties examined were Common, Venture, Castor, Palaton and Venture. Reed canarygrass was harvested three times annually, 1st cut(1O, May), 2nd cut(31, July), and 3rd cut(10, Oct.), respectively. The results were summarized as follows ; 1. Dry matter yield were not significant difference between varieties and for the interaction of variety$\times$cut. But, there was significant difference between cuts. 2. There was not significant difference in dry matter yield between the first cut and second cut. But, the dry matter yield of the third cut was poor than the other two cuts. Thus, the average dry matter yield of varieties were 806.1 kg, 730.8kg and 495.8kg /l0a in the first, second and third cut, respectively. 3. In Venture and Palaton, the percentage of dry matter distribution in spring was higher than that of other varieties. In Common, Castor and Vantage, they were not significantly different between the percentage of dry matter distribution in each cut. Above the results suggested that the first group of varieties(Venture and Palaton) were suited to meadow and last group of varieties(Common, Castor and Vantage) were suited to pasture. 4. Average total dry matter yield of varieties was 2,032kg /l0a/yr,(ranged from 1,922kg to 2,180 kg /l0a /yr.)

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Efficiency of Mineral Nitrogen Fertilization on Yiled and Botanical Composition of Grassland II. Seasonal distribution of dry matter yield and economical mineral nitrogen application on grassland (무기태 질소시비가 초지의 수량과 식생구성에 미치는 영향 I. 초지수량의 계절적 분포와 경제적 무기태 질소시비한계)

  • ;G. Schechtner
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.10 no.3
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    • pp.158-163
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    • 1990
  • This experiment was to study the effect of pure mineral nitrogen fertilizing on seasonal distribution of dry matter yield and the advisable mineral nitrogen amounts on grassland. The results were as follows: 1. With longer regrowth periods the absolute dry matter yields and the nitrogen-efficiences due to nitrogen fertilizing increased substantially, whereas the quality declined at the relatively lesser cutting frequencies. 2. The first cut at 3-cut regimes, the first and fourth cut at 4-cut regimes, and the second and last cut at 5-and 6-cut regimes showed the highest nitrogen-efficiency, respectively. 3. By the sigmaformed process of production curve the most efficient mineral N-dressing rate per ha and cut was calculated: 42-56kg N on the 3-cut areas, 39-55kg N on the 4-cut areas, 38-47kg N on the 5-cut areas and 35-48kg N/ha/cut on the &cut areas. 4. In dependence on site and kind of calculation the economical borders were reached with the following dressings of mineral N/ha/cut: 90-100kg on the 3-cut areas, 70-100kg on the 4-cut areas and 50- 90kg on the 5-and 6-cut areas.

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Iron Status of Pregnant Women and Evaluation of Cut-off Levels of Hb, Hct, TIBC, sTfR, sTfR:ferritin Ratio for Assessment of Iron Deficiency (임신여성의 철영양상태와 철결핍상태 판정을 위한 Hb, Hct, TIBC, sTfR 및 sTfR:ferritin 비의 임계수준 평가s)

  • 이종임;임현숙
    • Korean Journal of Human Ecology
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    • v.4 no.1
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    • pp.36-45
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    • 2001
  • This study was performed to determine the changes of maternal iron status during pregnancy cross sectionally, and to evaluate the appropriateness of the cut-off points of hemoglobin (Hb). hematocrit (Hct), serum transferrin receptor (sTfR) and sTfR : ferritin ratio for assessing iron deficiency status based on serum ferritin level (< 12${\mu}g$/L). Serum Hb concentrations in the first trimester were significantly higher (p < 0.05) than those in the second and third trimester. Serum levels of iron and ferritin in the third trimester were significantly lower (p < 0.05) than those in the first and second trimester. On the other hand, sTfR:ferritin ratios in the third trimester were significantly higher (p < 0.05) than those in the first and second trimester. sTfR concentrations did not change significantly during pregnancy. The appropriate cut-off points of Hb were 11.5g/dL for whole period of pregnancy. 12.0g/dL for 1st trimester. and 11.5g/dL for both 2nd and 3rd trimester. The good cut-off points of Hct were 34% for whole period of pregnancy. 36% for 1st trimester. and 34% for both 2nd and 3rd trimester The suitable cut-off points of TIBC were 400${\mu}g$/dL for whole period of pregnancy. 360${\mu}g$/dL for 1st trimester, and 400${\mu}g$/dL for both 2nd and 3rd trimester. Any cut-off point of sTfR could not be selected because of its low sensitivity and specificity. The proper cut-off point of sTfR : ferritin ratio was 600 or 650 for all the periods determined except the first trimester. In conclusion, there were no reliable cut-off levels of sTfR and those of sTfR : ferritin ratio showed low specificity. The cut-off values of Hb and Hct for assessing iron deficiency were slightly higher than the values used to evaluate anemia. Thus, if appropriate cut-off levels were applied, Hb. Hct, or TIBC might be useful indices for evaluating iron deficiency as well as anemia.

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Cutting Force Test of Cutting Blade Modules for Slitter Design

  • Kim, Young-Hwan;Cho, Yung-Zun;Lee, Young-Soon
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2017.10a
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    • pp.189-190
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    • 2017
  • For the concept design of the device, a tool was made to test the simulated fuel rods and cutting force and the cutting force was measured. When 2-CUT and 3-CUT modules were used, the maximum force in 2-CUT at 12.5 mm/s speed change was $197.5kg_f$ and the maximum force at 3-CUT was $363.2kg_f$. The change of force in 2-CUT rapidly increases from about 1 second, and you can see that there are increase and decrease of the force change from about 5 seconds to 18 seconds, and it was rapidly decreased and the cut was made. The force change in 3-CUT has higher force at about 5 seconds later than 2-CUT at the speed of 12.5 mm/s, and you can see that it has the same tendency afterwards. If you search for the force at adequate speed from this cutting force test, 2-CUT module requires less slitting force than 3-CUT module, and the cutting time for 250 mm at 12.5 mm/s was 21 seconds, which can cut 4 m fuel rod in 5 minutes. But, there are cases of not completely slitting with 2-CUT module, so it is necessary to supplement this in the future through experiments.

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Analysis on the production and consumption of the cut lily bulb in world market (세계 시장에서의 절화 백합의 생산 및 소비 분석)

  • Kim, Sounghun;Kim, Jootae
    • Korean Journal of Agricultural Science
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    • v.42 no.1
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    • pp.73-79
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    • 2015
  • The cut lily is one of the most important exporting flowers in Korea, which value is 19.9 million dollars in 2013. However, Korean farmers and exporting firms recently have experiences a large decrease in lily export, and need to find the way to the increasing exportation. The purpose of this paper is to analyze the situation of production and consumption of the cut lily in the world and to present the implication for the acceleration of exportation of Korean cut lily. The results of studies present a few findings: First, Korean farmers and business firms need to study and benchmark the production and exportation system of Netherlands which is the best country in the world. Second, Colombia, Kenya, Ecuador and Ethiopia are also need to be studied for the upgrading Korean system of exportation of cut lily. Third, Korean farmers and business firms should continuously monitor the three main markets of cut lily (EU, U.S., and Japan), and develop strategies for the exportation of Korean cut lily. Forth, especially, Korean farmers and business firms should define the preference of cut lily in the main exporting markets (Japan, China, Russia), including breed and color of flower, and the main period of consumption, in order to develop the marketing strategy for Korean cut lily.

A Study on the Infiltration Characteristics of Soil Cut-Slope (토사절토사면의 침투특성에 관한 연구)

  • Lee, Jeong-Yeob;Koo, Ho-Bon;Kim, Seung-Hyun;Bae, Gyu-Jin
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.735-738
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    • 2005
  • The purpose of this study is the infiltration characteristics of soil cut-slope by rainfall. Stability analysis of soil cut-slopes has been conducted by limit equilibrium method on Seep/w and finite element method on Slope/w. Result is same as following. First. the hour when seepage line and groundwater in contact is proportionate from rainfall rate condition and upper natural slope gradient condition which is identical. Second, when seepage line and groundwater is contact, seepage line moves gradually at soil cut-slope surface. Finally, seepage line is formed similarly with soil cut-slope gradient. Third, when rainfall is ended, from the recording upper natural slope where the hour will pass it is stabilized

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Development of a Moldboard Plow to Invert Furrow Slice at the Same Position (토양의 제자리 반전을 위한 몰드보드 플라우의 개발)

  • 이규승;박원엽;권병기
    • Journal of Biosystems Engineering
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    • v.29 no.1
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    • pp.9-20
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    • 2004
  • On the basis of design theory of soil inversion, two types of moldboard plow with secondary soil mover was designed and constructed to invert furrow slice at same position with furrow bottom. A series of soil bin experiment was carried to investigate the performance of prototypes. First prototype of new concept plow showed two kinds of problems during the preliminary experiment. For the plowing depth of 6cut the prototype did not invert the furrow slice, instead it just cut furrow bottom and the furrow slice returned to the original position. For the plowing depth of 8cm, there was soil clogging problem at the rear part of plow. From the above results it was concluded that the first prototype can not be used for the inversion of furrow slice at same position with furrow bottom. Second prototype could invert furrow slice at the same position with furrow bottom, but the performance was affected by soil moisture content soil hardness and plowing speed very much. For the higher soil moisture content, for the higher soil hardness and higher plowing speed, the prototype showed higher soil inversion performance. For the second prototype the inversion ratio was almost 100%, inversion angle was in the range of 90 to 100 degree and side displacement was less than 4 cm. But the furrow slice was not continuous, it was cut in the length of 30 to 40 cm. The reason why the furrow slice was cut in that length is blamed for the design of moldboard surface. The specific draft of prototype was in the range of 37.24 kN/㎡ to 42.14 kN/㎡ this value is a little higher than that of the conventional plow, or from 30.38 kN/㎡ to 33.32 kN/㎡. But the difference was not so big. The inversion performance of the second prototype for the field experiment was much better than that of soil bin experiment due to the better soil and operational conditions. Sticky and compacted soil conditions, and higher plowing speed was suitable for the plowing operation of the second prototype