• Title/Summary/Keyword: yellow

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Feasibility of Domestic Yellow Poplar (Liriodendron tulipifera) Dimension Lumber for Structural Uses (국산 백합나무 구조용 제재목의 이용가능성 평가)

  • Lim, Jin-Ah;Oh, Jung-Kwon;Yeo, Hwan-Myeong;Lee, Jun-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.38 no.6
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    • pp.470-479
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    • 2010
  • In this study, the visual grading based on the visual characteristics and structural timber bending test were conducted for domestic yellow poplar dimension lumber. Structural performance of domestic yellow poplar dimension lumber was conducted through the evaluation of strength and stiffness. Visual grading rule of yellow poplar dimension lumber did not exist in Korea. Visual grading of yellow poplar dimension lumber was performed according to the NSLB (Northern Softwood Lumber Bureau) standard grading rules including several hardwood dimension lumber. The allowable bending stress was calculated from the results of a visual grading. Compared with NDS (National Design Specification), the yellow poplar dimension lumber showed enough strength for structural uses. In addition, the visual grading was performed according to the KFRI (Korea Forest Research Institute) grading rule to calculated allowable bending stress and to evaluated the feasibility. The yellow poplar was classified into the pine groups by the KFRI criteria regulated by specific gravity. Allowable bending stress based on weibull distribution had became highly than KFRI criteria, as No. 1 (10.0 MPa), No. 2 (7.4 MPa) and No. 3 (4.1 MPa). And the availability of yellow poplar dimension lumber for structural uses had been confirmed. The Modulus of Elasticity (MOE) of domestic yellow poplar dimension lumber had not met the NDS and KFRI criteria. However, for the use of domestic yellow poplar, average values of MOE which obtained through this test were suggested as design value for domestic yellow poplar. Design values were supposed No. 1, 2 (9,000 MPa) and No. 3 (8,000 MPa).

Identifying Yellow Sand from the Ocean Color Sensor SeaWIFS Measurements (해색 센서 SeaWiFS 관측을 이용한 황사 판독)

  • 손병주;황석규
    • Korean Journal of Remote Sensing
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    • v.14 no.4
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    • pp.366-375
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    • 1998
  • Optical characteristics of the yellow sand and their influences on the ocean color remote sensing has been studied using ocean color sensor SeaWiFS measurements. Two cases of April 18 and April 25, 1998, representing yellow sand and background aerosol, are selected for emphasizing the impact of high aerosol concentration on the ocean color remote sensing. It was shown that NASA's standard atmospheric correction algorithm treats yellow sand area as either too high radiance or cloud area, in which ocean color information is not generated. Optical thickness of yellow sand arrived over the East Asian sea waters in April 18 indicates that there are two groups loaded with relatively homogeneous yellow sand, i.e.: heavy yellow sand area with optical thickness peak around 0.8 and mild area with about 0.4, which are consistent with ground observations. The movement of the yellow sand area obtained from surface weather maps and backward trajectory analysis manifest the notion that the weak yellow sand area was originated from the outer region of the dust storm. It is also noted that high optical thickness associated with the yellow sand is significantly different from what we may observe from background aerosol, which is about 0.2. These characteristics allow us to determine the yellow sand area with an aid of atmospheric correction parameter. Results indicate that the yellow sand area can be determined by applying the features revealed in scattergrams of atmospheric correction parameter and optical thickness.

상동산 SCHEELITE의 특성연구 <특히 Powellite 진부 구명을 위하여>

  • 황재운
    • Journal of the Korean Professional Engineers Association
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    • v.3 no.10
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    • pp.3-6
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    • 1970
  • The scheelite occurred in Sang Dong mine are disseminated with a fine grain, and shelved pale blue or white color under the fluorescence. But among them, We can often observe the yellow fluorescent color mineral grains, which were called the powellite from the past time without any detail mineral study. I studied the characteristics of Sang-Dong scheelite and the so called powellite. In the result, the so called powellite is proved to be the molybdenum bearing scheelite in the view of specific gravity, index of refraction, chemical composition, other microscopic properties, and dressing. Such a scheelite is contained usually Zor 3% Mo, and oftenly 4 or 6% Mo, and fluorescent colors are pale yellow, leman yellow and chrome yellow.

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The Bodotriid Cumacea (Crustacea: Malacostraca) from the Yellow Sea

  • Park Mi-Ra;Hong Jae-Sang;Choi Kwang-Sik
    • Fisheries and Aquatic Sciences
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    • v.1 no.1
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    • pp.94-112
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    • 1998
  • The present study dealt with cumaceans (Cumacea: Bodotriidae) collected from the Yellow Sea. Specimens were sampled using a van Veen grab m the Yellow Sea and in. Kyonggi Bay surrounding Inchon, Korea. New figures and redescriptions of the four bodotiid cumaceans are presented including Bodotria ovalis Gamo, 1965, Iphinoe tenera Lomakina, 1960, Eocuma cf. hilgendorfi Marcusen, 1894, and Heterocuma sarsi Miers, 1879. They are newly added in the Korean fauna.

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Recent Environmental Changes Influenced by Human Being in Lower Reach of Yellow River (황하강 하류지역에서의 인간에 의한 최근 환경변화)

  • Qingsong, Zhang
    • Journal of the Korean Geographical Society
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    • v.33 no.spc
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    • pp.729-738
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    • 1998
  • Under background of global change, regional and local environmental changes in short-term are significantly influenced by human activities in recent time. This paper deals with serious environmental problems which has become a barrier of sustainable development in the lower reach of Yellow River due to over use of diverted water from Yellow River and underground water from coastal plain. Some countermeasures for improving local environment and economic development are introduced in the paper.

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Occurrence and Ecological Characteristics of Colour Morphs of the Green Peach Aphid, Myzus Persicae (Sulzer) (Homoptera : Aphididae) in Tobacco Field (담배포장에서의 복숭아혹진딧물 체색형별 발생과 생태적 특성)

  • 손준수;송유한
    • Journal of the Korean Society of Tobacco Science
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    • v.16 no.1
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    • pp.76-83
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    • 1994
  • The dominant colour - types of fundatrices of green peach aphid, Myzsts persicae 5. were yellow - green, red and green. Yellow type was the minority among nymphs produced by field collected alatae. Rate of producing dead nymphs was over 34.0% in red and yellow types apterae grown from tobacco plants in early summer. Brown and green were the dominant colour - type in apterae throughout tobacco growing season. Brown type on tobacco, and yellow type on hot pepper and tomato grew better and produced more nymphs than other colour - types.

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An Aggregate Fairness Marker without Per Flow Management for Fairness Improvement of Assured Service in DiffServ (DiffServ 방식의 Assured Service 에서 플로별 관리 없이 Fairness향상을 위한 Aggregate Fairness Marker)

  • Park, Ji-Hoon;Hur, Kyeong;Eom, Doo-Seop
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.7B
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    • pp.613-627
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    • 2004
  • In this paper, we propose an Aggregate Fairness Maker (ARM) required for an Edge router to improve fairness of throughput among the flows of Assured Service in DiffServ with different round trip time (RTT) and we propose a user flow Three Color Marker (uf-TCM) as a flow marker that marks packets from the flow as green, yellow, or red. A yellow packet is the packet that consumes loss token in uf-TCM as well as that is demoted green packet in AM due to disobey the aggregate traffic profile. The proposed AFH promotes yellow packet to green packet or demotes green packet to yellow packet through the fair method without per-flow management, and it improves the feirness of throughput among the flows as well as link utilization. A yellow packet and a red packet have the same drop precedence at Core Router in our scheme. So we can use the RIO buffer management scheme. We evaluated the performance of our proposed AFM and the REDP Marker that was proposed to improve fairness without per-flow management. Simulation results show that, compared with the REDP marker, proposed AFM can improve performance of throughput fairness among the flows with different RTT and link utilization under the over-provisioning, exact-provisioning, and under-provisioning network environments at Multiple DiffServ domains as well as at Single DiffServ domain.

Efficiency of Yellow and White light Traps on Controlling Tobacco Whitefly in tomato Greenhouse (토마토 온실에서 담배가루이 성충에 대한 노란색 및 백색 트랩의 방제효과)

  • Lee, Jung-Sup;Lee, Jae-Han;Park, Kyung-Seob;Yeo, Kyung-Hwan;Kim, Jin-Hyun;Kweon, Jun-Kuk
    • Journal of Bio-Environment Control
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    • v.26 no.4
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    • pp.432-437
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    • 2017
  • Yellow sticky traps have been commonly used for monitoring tobacco whitefly populations in open-fields, as well as in greenhouses. However, the attractiveness depends on various factors such as the reflected intensity (brightness) and hues of yellow color (wavelength) of the trap surface, which is often influenced by environmental conditions and may sometimes affect tobacco whitefly capture. Therefore, the use of light-emitting traps can be a significant complementary tool to strengthen the attractiveness and selectivity of these traps. This research was carried out in tomato greenhouses to evaluate the light-emitting trap as potential attractants for Bemisia tabaci adults. The results showed that B. tabaci adults on average preferred (p>0.05) traps in yellow lights (590 nm) ($168{\pm}7.6adults/trap$) compared to traps in white lights ($106{\pm}4.6adults/trap$) and traps without lights ($60{\pm}4.8adults/trap$). The yellow light trap(590 nm) showed the most attractive to B. tabaci adults, followed by a little lower attraction to the white light trap(450-625 nm), whereas the control (no light trap) was little attractive to B. tabaci adults. These results suggested that yellow and white light traps could have a promising use in greenhouses for the identification, monitoring, and pest control tools of tobacco whiteflies.

Effects of Yellow Clay on the Production of Volatile Fatty Acids during the Anaerobic Decomposition of the Red Tide Dinoflagellate Cochlodinium polykrikoides in Marine Sediments (해양퇴적층에서 적조생물(Cochlodinium polykrikoides)의 혐기성 분해과정 중 황토가 휘발성 지방산 생성에 미치는 영향)

  • Park, Young-Tae;Lee, Chang-Kyu;Park, Tae-Gyu;Lee, Yoon;Bae, Heon-Meen
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.45 no.5
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    • pp.472-479
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    • 2012
  • The formation of volatile fatty acids(VFAs) and changes in pH, oxidation and reduction potential(Eh) and acid volatile sulfide(AVS) with the addition of yellow clay were investigated using microcosm systems to examine the effects of yellow clay dispersion on the anaerobic decomposition of Cochlodinium polykrikoides in marine sediments. The acetate concentration reached a maximum by day 4 and was 1.2-1.8 fold less in the sample treated with yellow clay compared to the untreated sample (224-270 vs. 333 uM). The formate concentration reached a maximum by day 1 and was 1.3-2.8 fold less in the sample treated with yellow clay compared to the untreated sample (202-439 vs. 563 uM). The propionate concentration reached a maximum by day 2 and was 1.5-1.8 fold less in the sample treated with yellow clay compared to the untreated sample (32.6 vs. 57.2 uM). After the amounts of acetate, formate and propionate peaked the levels dropped dramatically due to the utilization by sulfate reducing bacteria. The Eh of the samples treated with yellow clay was similar to the untreated sample on day 0 but was higher in the sample treated with yellow clay(140-206 mV) from days 4 to 17. AVS started to form on day 3 and this was sustained until day 6, and 1.2-2.2 fold less was produced in the sample treated with yellow clay compared to the untreated sample (40.2-69.3 vs. 83.2-93.8 mg/L). Accordingly, during the anaerobic decomposition of C. polykrikoides in marine sediments, yellow clay dispersal seems to suppress the reduction state of Eh and the formation of volatile fatty acids(acetate, formate and propionate) used as an energy source by sulfate reducing bacteria, indicating that this process controls the production of hydrogen sulfide that negatively affects marine organisms and the marine sediment environment.