• Title/Summary/Keyword: Covering methods

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Features of Temperature Distribution of Exposed Reinforcement Bars Depending on Changes of Covering Methods of Bubble Sheets (버블시트 피복방법 변화에 따른 동절기 노출철근의 온도분포 특성)

  • Lee, Jea-Hyeon;Lee, Sang-Un;Lee, Joung-Gyo;Yang, Seong-Hwan;Kyung, Yeong-Hyeok;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2016.05a
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    • pp.11-12
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    • 2016
  • The contemporary buildings are becoming super-taller gradually as the industry evolves. Accordingly, winter concrete also became an important element for the year-round construction since shortening of a construction duration became important. Accordingly, this research team once developed a double bubble sheet as concrete cover curing compound during winter. But since there is no proper countermeasure for the exposed reinforcement bars, it is worried that the concrete can be damaged by exposed frozen reinforcement bars at a low temperature during the initial period. Therefore, in this study, it is intended to review the temperature history of the reinforcement bars depending on changes of the covering methods of the exposed reinforcement bars by using bubble sheets.

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Effects of Weed Control on Pseudocercospora vitis and Fruit Characteristics in Campbell Early Vineyard (캠벨얼리 포도원에서 잡초관리 방법이 갈색무늬병 및 과실특성에 미치는 영향)

  • Kim, Sun-Kook;Choi, Won-Ho;Lee, Seok-Ho;Lee, Yun-Sang;Yoon, Changmann;Hong, Seong-Tac
    • Korean Journal of Organic Agriculture
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    • v.23 no.4
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    • pp.897-909
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    • 2015
  • This study was conducted to evaluate the effect of weed control on disease incidence, plant growth and fruit quality, and to provide effective method to farmers at the vineyard. At the raincoat greenhouse cultivating 'Campbell Early', several weed controlling methods were compared to the control. Mean temperature of plots between soil covering (C.B., W.F., S.N., P.F. and R.H.) and non soil covering (M.W.2, M.W.3 and U.T.) were similar with $26.2^{\circ}C$ (July) and $25.8^{\circ}C$ (Aug.), but humidity of soil covering was sharply decreased in late-July under 40%. Soil water were all higher in soil covering plots than that of non-soil covering, however, soil temperature was recorded lower in soil covering plots. Disease incidence of Peudocercospora vitis according to soil coverings had effect on black plastic film mulching by decreasing grapevine leaf spot to 85% in July, 69% in August, compared to the control, with showing the smallest lesion incidence in FMB. Among growth characters, internode length and internode width of black plastic film mulching was higher than that of the control. SPAD value of black plastic film mulching was recorded the highest. It was not significant among the treatments, but brix was recorded highly in black plastic film mulching with $14{\sim}15^{\circ}Brix$.

Evaluation of Surface Covering Methods for Reducing Soil Loss of Highland Slope in Soybean Cultivation (고랭지 경사 밭 콩 재배지에서 토양유실경감을 위한 피복방법 평가)

  • Lee, Jeong-Tae;Lee, Gye-Jun;Ryu, Jong-Soo;Kim, Jeom-Soon;Han, Kyung-Hwa;Zhang, Yong-Seon
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.5
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    • pp.725-732
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    • 2012
  • There is relatively high vulnerability of soil erosion in slope highland agriculture due to a reclamation of mountain as well as low surface covering during early summer with high rainfall intensity. Especially, in soybean cultivation, soil disturbance by conventional tillage and exposure of topsoil at the early stage of soybean have intensified soil loss. The aim of this study was to evaluate various surface covering methods for reducing soil loss in highland soybean cultivation. The experiment was conducted in 17% sloped lysimeter ($2.5m{\times}13.4m$) with 8 treatments. Amount of runoff water and eroded soil, and soybean growth were investigated. Surface covering through sod culture and plant residue showed 3.4~45.0 runoff water amount with $177{\sim}2,375m^3\;ha^{-1}$ compared with control ($5,274m^3\;ha^{-1}$). And the amount of eroded soil was also reduced by 95% in surface covering treatment with $0.02{\sim}1.94Mg\;ha^{-1}$ than control with $40.72Mg\;ha^{-1}$. Yields of soybean pod showed $0.3Mg\;ha^{-1}$ in rye sod culture, $1.3Mg\;ha^{-1}$ in Ligularia fischeri var. spiciformis Nakai, $0.7Mg\;ha^{-1}$ in Aster koraiensis Nakai, $0.2Mg\;ha^{-1}$ in red clover and $2.0Mg\;ha^{-1}$ in non-covering, on the other hand, covering with cut rye showed $3.8Mg\;ha^{-1}$. Conclusively, covering the soil surface with cut rye were beneficial for reduction of soil loss without decreasing soybean yield in highland sloped fields.

Effects of Covering Newborn's Head after Bath on Body Temperature, Heart Rate and Arterial Oxygen Saturation

  • Kim, Dong-Yeon;Park, Ho-Ran
    • Child Health Nursing Research
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    • v.18 no.4
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    • pp.201-206
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    • 2012
  • Purpose: In this study changes were observed in body temperature, heart rate and arterial oxygen saturation (SaO2) of newborns after bathing and to determine the effects of covering their heads with cotton hats after bathing. Methods: Participants were 58 newborn infants, 31 in the experimental group had their heads covered with cotton hats after their bath while 27 in the control group did not. Body temperature, arterial oxygen saturation and heart rate were measured at 8 consecutive times after bathing. Data were analyzed using t-test and repeated measures ANOVA. Results: Body temperature declined shortly after bathing. The experimental group showed faster recovery (p<.001). Heart rate increased after bathing in both groups. Heart rate in the experimental group decreased for 120 minutes and gradually increased to baseline (p<.001). In the control group, heart rate decreased for 180 minutes and then increased but did not reach the baseline (p<.001). Arterial oxygen saturation decreased shortly after bathing and recovery to the baseline was more rapid in the experimental group (30 minutes vs. 60 minutes) (p<.001). Conclusion: With significant changes observed in newborns' body temperature, arterial oxygen saturation and heart rate, covering the head right after bathing is effective in stabilizing infants' physiological system.

Changes in the Covering of Pupil and the Visual Acuity by the Illuminance when Wearing Circle Soft Contact Lens (써클 소프트콘택트렌즈 착용 시 조도에 따른 동공의 가려짐과 시력 변화)

  • Kim, So Ra;Choi, Jae Hyung;Lee, Kang-Geun;Park, Mijung
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.1
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    • pp.19-25
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    • 2013
  • Purpose: The degree of the pupil covered with tinted region of circle soft contact lens was determined according to the illuminant conditions in everyday life and the change of visual acuity by its covering was further investigated. Methods: The circle contact lens having the non-tinted area of 6.2 mm in the center of the lens was applied on 82 eyes in their 20s and their minimum separable visual acuity and minimum legible visual acuity were determined under the luminances of 50 and 370 lux. Results: The covering of pupil was not found when wearing circle contact lens under 370 lux, however, some pupil covering ranged from 0.40 to 1.70 mm was observed in all subjects under 50 lux. The minimum separable visual acuity and minimum legible visual acuity were significantly decreased by the wearing of circle contact lens under 50 lux and the correlation between the larger pupil size of subjects and more decrease of visual acuity was observed. Furthermore, the decrease of minimum separable visual acuity was larger than the case of minimum legible visual acuity indicating that minimum separable visual acuity was largely affected by the covering of pupil. Conclusions: The consideration is necessary for the lens wearers and the manufacturers since the wearing circle contact lens in low-light indoor or nighttime activities may affect directly visual acuity.

Estimation of Heat Insulation and Light Transmission Performance According to Covering Methods of Plastic Greenhouses (플라스틱온실의 피복방식에 따른 보온 및 광투과 성능 평가)

  • Lee, Hyun-Woo;Kim, Young-Shik;Sim, Sang-Youn;Lee, Jong-Won;Diop, Souleymane
    • Journal of Bio-Environment Control
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    • v.22 no.3
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    • pp.270-278
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    • 2013
  • The objective of the present study is to provide data needed to decide covering method to be able to increase the thermal insulation and light transmittance efficiency of commercial greenhouse. The thermal insulation effect, PPF transmittance and quantity of condensation water were estimated in experimental tomato greenhouses covered with three types of coverings of single layer, air inflated and conventional double layers covering. The overall heat flow of air inflated double layers greenhouse was similar to that of conventional double layers greenhouse, but the temperature between covering material and thermal screen in air inflated double layers greenhouse was lower than that in conventional double layers greenhouse at the same outside temperature condition due to air leakage through the gap of roof vent. The overall heat transfer coefficients acquired by experiment that was performed in single layer and conventional double layers greenhouses were close to those obtained from model experiment. Even though the PPF transmittance of air inflated double layers greenhouse was lower than that of single layer greenhouse, which was greater than that of conventional double layers greenhouse. The quantity of condensation water on covering surface of single layer greenhouse was greater than that of air inflated double layers greenhouse due to lower covering surface temperature.

Establishment of Disposing Method for Dairy Cow Manure by Vermiculture (지렁이를 이용한 젖소분뇨 처리에 관한 연구)

  • 나영은;한민수;이상범;김세근;박형만
    • The Korean Journal of Soil Zoology
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    • v.5 no.2
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    • pp.125-131
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    • 2000
  • Disposing technique for dairy cattle manure using earthworms and the possibility of utilizing earthworms in poultry feed were investigated. In addition, chemical properties of manure and cast of earthworms were investigated. Temperature in the vinyl-house for earthworm nursery was able to be maintained above 0$\^{C}$ in winter and 25-28$\^{C}$ in summer. In closed-covering method, the number of escaped earthworms was the highest among three covering methods. The time was longer after manure excretion, the numbers of escaped earthworm were higher. There were some incidences of mortality of earthworm in closed-covering site. The amount of manure ingested by earthworm was increased in order of non-covering, closed-covering and gap-covering method. Fresh manure was more ingested than old one by earthworm. Earthworms reduced manure about 50% on the dry weight base and reduced total amounts of N, P$_2$O$\_$5/ and K$_2$O of manure by 41, 50 and 60%, respectively. Earthworm could be utilized by adult poultry (>60 g) for feeding. However, adverse effect of live earthworm was observed with young poultry (<450 g).

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Effect of Covering Method of Ventilating Non-Woven Fabric and $\textrm{GA}_3$ Treatment on the Growth and Yield of Leaf Lettuce during Low Temperature Season (통기성 부직포의 피복방법 및 $\textrm{GA}_3$ 처리가 저온기에 잎상추의 생육 및 수량에 미치는 영향)

  • 최영환;손병구;강점순;안종길
    • Journal of Bio-Environment Control
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    • v.12 no.2
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    • pp.72-76
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    • 2003
  • This study was conducted to estimate stimulation of plant growth of green and red leafy lettuces (Lactuca sutiva L. cv. Chungchima and Jugchima) at affected by covering method and time with protected film materials containing concentrated PO film and GA$_3$ foliar spray. Plants were covered with ‘Pasraido’ material from October 26 to November 31 (direct 1), from November 5 to November 31 (direct 2), or with a tunnel, or direct 2+ tunnel. Mean air temperature and relative humidity under the covering were higher in direct and tunnel, direct and non-covering, in that order. The fresh weight and dry weight of red and green lettuces increased in direct and tunnel followed by direct 1, direct 2, tunnel and the control. GA$_3$ treatment promoted the growth in all covering methods, but decreased the chlorophyll contents. Fresh weight and dry weight were higher in red lettuce than in green lettuce in the control.

Nearest Neighbor Based Prototype Classification Preserving Class Regions

  • Hwang, Doosung;Kim, Daewon
    • Journal of Information Processing Systems
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    • v.13 no.5
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    • pp.1345-1357
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    • 2017
  • A prototype selection method chooses a small set of training points from a whole set of class data. As the data size increases, the selected prototypes play a significant role in covering class regions and learning a discriminate rule. This paper discusses the methods for selecting prototypes in a classification framework. We formulate a prototype selection problem into a set covering optimization problem in which the sets are composed with distance metric and predefined classes. The formulation of our problem makes us draw attention only to prototypes per class, not considering the other class points. A training point becomes a prototype by checking the number of neighbors and whether it is preselected. In this setting, we propose a greedy algorithm which chooses the most relevant points for preserving the class dominant regions. The proposed method is simple to implement, does not have parameters to adapt, and achieves better or comparable results on both artificial and real-world problems.

Vibration control laws via shunted piezoelectric transducers: A review

  • Qureshi, Ehtesham Mustafa;Shen, Xing;Chen, JinJin
    • International Journal of Aeronautical and Space Sciences
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    • v.15 no.1
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    • pp.1-19
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    • 2014
  • Attaching a piezoelectric transducer to a vibrating structure, and shunting it with an electric circuit, gives rise to different passive, semi-passive, and semi-active control techniques. This paper attempts to review the research related to structural vibration control, via passive, semi-passive, and semi-active control methods. First, the existing electromechanical modeling is reviewed, along with the modeling methods. These range from lumped parameters, to distributed parameters modeling of piezostructural systems shunted by electrical networks. Vibration control laws are then discussed, covering passive, semi-passive, and semi-active control techniques, which are classified according to whether external power is supplied to the piezoelectric transducers, or not. Emphasis is placed on recent articles covering semi-passive and semi-active control techniques, based upon switched shunt circuits. This review provides the necessary background material for researchers interested in the growing field of vibration damping and control, via shunted piezostructural systems.