• Title/Summary/Keyword: REED

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Effect of Cutting Freqensy and Leavel of Nitrogen Fertilization on Carbohydrate Resreves of Reed Canarygrass (예취빈도 및 질소시비수준이 Reed Canarygrass의 저장탄수화물함량에 미치는 영향)

  • 서흥종;육완방
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.2
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    • pp.89-97
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    • 1992
  • This experiment was attempted to investigate the effects of growing stage, cutting frequency and the level of nitrogen fertilization on the change of carbohydrate reserves in reed canarygrass(Pha1aris arundinacea L.). The results obtained were as follows: The amount of carbohydrate reserves appeared to markedly decrease up to critical level after the cutting in hot and dry weather season. During the growing stage, the amount of carbohydrate reserves decreased just after the cutting and also during the period of flourishing elongation of reed canarygrass. However, it began to increase sharply from the end of September for wintering. Two cutting system showed the highest mean value(19.53 %) of carbohydrate reserves and those of three, five and four cutting system was 15.32 %. 14.73 %, and 14.60 % respectively. Reed canarygrass with no nitrogen fertilization resulted in 17.17% of carbohydrate reserve, however there was no singificant difference among various levels of nitrogen fertilization. In respect of regrowth. 3 cutting system showed the most effective cutting frequency, however 4 or 5 cutting system had a decreasing tendency of regrowth.

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Direct Decoding Algorithm of (128, 124) Reed-Solomon Codes for ATM adaptation laye and Its VHDL Simulation (ATM 적응계층에 적용 가능한 (128, 124) Reed Solomon 부호의 직접복호법 및 VHDL 시뮬레이션)

  • 김창규
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.10 no.1
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    • pp.3-11
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    • 2000
  • AAL-1에서는 (128, 124) Reed-Solomon부호를 사용한 인터리버 및 디인터리버에 의해 ATM 셀에서 발생하는 오류를 정정하고 있다. Reed-Solomon부호의 복호법 중 직접복호법은 오류위치다항식의 계산없이 오류위치와 오류치를 알 수 있으며 유한체 GF(2m)의 표현에서 정규기저를 사용하면 곱셈과 나눗셈을 단순한게 비트 이동만으로 처리할 수 있다. 직접복호법과 정규기저를 사용하여 ATM 적응계층에 적용 가능한 (128, 124) Reed-Solomon부호의 복호기를 설계하고 VHDL로 시뮬레이션 하였으며 이 복호기는 동일한 복호회로에 의해 둘 또는 하나의 심벌에 발생한 오류를 정정할 수 있다.

EFFECTS OF CUTTING FREQUENCY AND NITROGEN FERTILIZATION ON DRY MATTER YIELD OF REED CANARYGRASS (Phalaris arundinacea L.) IN UNCULTIVATED RICE PADDY

  • Lee, J.S.;Ahn, J.H.;Jo, I.H.;Kim, D.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.9 no.6
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    • pp.737-741
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    • 1996
  • Dry matter yield of reed canarygrass was investigated in uncultivated rice paddy in Korea, and an attempt was made to estimate the most economic and efficient cutting frequency and rates of nitrogen (N) fertilization, for increased production of reed canarygrass. Total dry matter yields of reed canarygrass per year were 7.4-15.7, 8.5-16.1, and 7.5-13.4 tons/ha in 3, 4, and 5 cutting frequencies, respectively, and over the N treatments of 0-120 kg N/ha/cut. When cut 3 or 5 times annually, the 2nd cut produced the highest proportion of total yield at 38.4 and 33.0%, respectively, when cut 4 times the 3rd cut was highest (38.3%). The ranges of economic N level, limiting N level and efficiency of dry matter production were 243.3-293.0, 387.2, and 14.6 kg DM/kg N, respectively. These indicators were particularly low for the 5 cutting frequency possibly because of the unusually high temperature in the summer season. The best cutting frequency for the dry matter production of reed canarygrass in 1994 was 3 per year because of the higher efficiency of dry matter production.

Hybrid-ARQ protocols based on first-order reed-muller codes with soft decision detectors (연판정 검출기를 사용한 1차 reed-muller 부호에 근거한 복합 자동반복요구 프로토콜)

  • 황원택;김동인
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.5
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    • pp.1256-1265
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    • 1996
  • Soft-decision detectors are used in many FEC and ARQ schemes to enhance the bit-error-probability and system throughput. Also, the hybrid-ARQ protocol is a very efficient schemeto achieve overall performance improvement. In this paper, we propose a new hybrid-ARQ protocol based on the first-order Reed-Muller codes employing soft-decision detectors. The Reed-Muller codes have the virtue of being able to use the fast Green machine decoder that is simple to implement. As the performance measures, the bit-error-probability and system throughput are evaluted for the proposed hybrid-ARQ procol, and compared with those of other hybrid-ARQ schemes. It is shown that the use of the proposed hybrid-ARQ protocol results in significant performance improvement without causing much loss in view of system complexity.

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Design of Triple-Error-Correcting Reed-Solomon Decoder using Direct Decoding Method (Reed-Solomon 부호의 직접복호법을 이용한 3중 오류정정 복호기 설계)

  • 조용석;박상규
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.8A
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    • pp.1238-1244
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    • 1999
  • In this paper, a new design of a triple-erroe-correcting (TEC) Reed-Solomon decoder is presented based on direct decoding method which is more efficient for the case of relatively small error correction capability. The proposed decoder requires only 9 GF(2m) multipliers in obtaining the error-locator polynomial and the error-evaluator polynomial, whereas other decoders needs 24 multipliers. Thus, the attractive feature of this decoder is its remarkable simplicity from the point of view of implementation. Futhermore, the proposed TEC Reed-Solomon decoder has very simple control circuit and short decoding delay. Therefore this decoder can be implemented by simple hardware and also save buffer memory which stores received sequence.

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Horizontal Flow Zeolite-Filled Reed Bed for Treatment of Artificial Sewage with Intermittent Feeding (수평 흐름 제올라이트 갈대 여과상에 의한 인공하수 처리)

  • 서정윤;최민수
    • KSBB Journal
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    • v.18 no.6
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    • pp.506-510
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    • 2003
  • The artificial sewage was treated using a horizontal flow zeolite-filled reed bed. The artificial sewage was fed into the reed bed for 10 minutes every 6 hours at the hydraulic load of 314 L/㎡$.$day. The filtering height of the reed bed was 100 cm and the zeolite mixture was filled in the reed bed. The mixttjre consisted of the same volume of two types of zeolite: 0.5∼l mm and 1∼3 mm in diameter. Annual average removal efficiency was CODcr 95.8%, T-N 56.5%, NH$\_$4/$\^$+/-N 99.4% and T-P 61.3%. T-N removal efficiency decreased remarkably from 84 to 32% with the operating time.

Uptake Patterns of N and P by Reeds (Phragmites australis) of Newly Constructed Shihwa Tidal Freshwater Marshes (시화지구 인공습지에서 갈대에 의한 질소 및 인 흡수)

  • 노희명;최우정;이은주;윤석인;최영대
    • The Korean Journal of Ecology
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    • v.25 no.5
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    • pp.359-364
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    • 2002
  • This study was conducted to examine the seasonal pattern of N and P uptake by reeds (Phragmites australis) planted in newly constructed Shihwa tidal freshwater marshes. Reed and soil samples were collected from the wetland periodically from June 2000 to May 2002. Reed samples were analyzed for dry weight and content of N and P Soil organic matter content and salinity were also determined. Dry matter content of reed increased during the growing season but decreased in the fall and winter. However, this seasonal pattern was not so evident in the second year. In particular, throughout the measurement period, dry matter content of reed was lowest at a site showing high soil salinity. Regression analyses between dry matter content of reed and soil EC(1:5) suggested that dry matter content per unit square meter would decrease by 1.5 kg with every 1 dS m/sup -1/ increase in soil EC(1:5). The amount of N and P assimilated by reed significantly decreased from the fall and was lowest in the spring. Net decrease in N content from reed during the fall and next spring was calculated as 34.5 and 24.6 g m/sup -2/ in the first and second years, respectively, while the corresponding P loss was 4.0 and 1.8 g m/sup -2/. Soil organic mailer content increased in the fall and winter, but decreased in the spring and summer. The results of this study suggested that the removal of N and P by reed would be considerable during the growing season but the nutrients taken up by reeds would return as detritus to the marshes in the fall and winter. Based on the results of the study, therefore, the harvest of the reed at the latter part of the growth would be recommended to prevent further water quality degradation. However, the long-term effects of reed harvest needs further study.

Research for Carbon Dioxide Fluctuation using Drone above the Mud Flat and Reed Beds in the Suncheon Bay (드론 관측을 통한 순천만 갯벌과 갈대밭 상부 대기의 이산화탄소 농도 분포 연구)

  • Kang, Dong-hwan;Jo, Won Gi;Yun, Yeon Su;Yu, Hun Sun;Jang, Seon Woong;Kim, Dong Lib;Park, Jeong Hwan;Song, Young Chul;Choi, Yong Jae
    • Journal of Environmental Science International
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    • v.29 no.7
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    • pp.703-713
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    • 2020
  • In this study, carbon dioxide concentration and air temperature at different elevations were observed and analyzed in the upper atmosphere of mud flat and reed beds at low tide in Suncheon Bay. The carbon dioxide concentration and air temperature sensors were mounted on the drone, and the carbon dioxide concentration and air temperature by altitude (5 m, 10 m, 20 m, 40 m) at five points in the tidal flat and reed beds were observed in the morning and afternoon. The carbon dioxide concentrations in the upper atmosphere of the tidal flat ranged from 453.0 to 460.2 ppm in the morning and 441.6 to 449.7 ppm in the afternoon. The carbon dioxide concentrations in the upper atmosphere of the reed beds ranged from 448.9 to 452.4 ppm in the morning and 446.0 to 454.4 ppm in the afternoon. The carbon dioxide concentrations in the upper atmosphere of the tidal flat was higher in the morning than in the afternoon, and the carbon dioxide concentration decreased as the altitude increased. The carbon dioxide concentration in the upper atmosphere of the reed beds was similar in the morning and afternoon at all altitudes, and the carbon dioxide concentration decreased as the altitude increased. The correlation coefficient between carbon dioxide concentration and air temperature observed in the tidal flat in the morning was -0.54 ~ -0.77, and the correlation coefficient between carbon dioxide concentration and air temperature observed in the afternoon was 0.56 ~ 0.80. The correlation coefficient between carbon dioxide concentration and temperature observed in the morning in the reed field was low, below 0.3, and the correlation coefficient between carbon dioxide concentration and air temperature observed in the afternoon was 0.35 ~ 0.77. In the upper atmosphere of the tidal flats and reed beds, the linear function was suitable for the change of carbon dioxide concentration as a air temperature, and the coefficient of determination of the estimated linear function was higher in the afternoon than in the morning. Through this study, it was confirmed that the carbon dioxide concentration in the upper atmosphere of the tidal flat and the reed beds was different, and the increase rate of carbon dioxide concentration in the upper atmosphere of the tidal flat and the reed beds was higher in the afternoon than in the morning.

Reduction of Chattering Error of Reed Switch Sensor for Remote Measurement of Water Flow Meter (리드 스위치 센서를 이용한 원격 검침용 상수도 계량기에서 채터링 오차 감소 방안 연구)

  • Ayurzana, Odgerel;Kim, Hie-Sik
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.44 no.4 s.316
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    • pp.42-47
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    • 2007
  • To reduce the chattering errors of reed switch sensors in the automatic remote measurement of water meter a reed switch sensor was analyzed and improved. The operation of reed switch sensors can be described as a mechanical contact switch by approximation of permanent magnet piece to generate an electrical pulse. The reed switch sensors are used mostly in measurement application to detect the rotational or translational displacement. To apply for water flow measurement devices, the reed switch sensors should keep high reliability. They are applied for the electronic digital type of water flow meters. The reed switch sensor is just mounted simply on the conventional mechanical type flow meter. A small magnet is attached on a pointer of the water meter counter rotor. Inside the reed sensor two steel leaf springs make mechanical contact and apart repeatedly as rotation of flow meter counter. The counting electrical contact pulses can be converted as the water flow amount. The MCU sends the digital flow rate data to the server using the wireless communication network. But the digital data is occurred difference or won by chattering noise. The reed switch sensor contains chattering error by it self at the force equivalent position. The vibrations such as passing vehicle near to the switch sensor installed location causes chattering. In order to reduce chattering error, most system uses just software methods, for example using filter algorithm and also statistical calibration methods. The chattering errors were reduced by changing leaf spring structure using mechanical characteristics.

New Low-Power and Small-Area Reed-Solomon Decoder (새로운 저전력 및 저면적 리드-솔로몬 복호기)

  • Baek, Jae-Hyun;SunWoo, Myung-Hoon
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.6
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    • pp.96-103
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    • 2008
  • This paper proposes a new low-power and small-area Reed-Solomon decoder. The proposed Reed-Solomon decoder using a novel simplified form of the modified Euclid's algorithm can support low-hardware complexity and low-Power consumption for Reed-Solomon decoding. The simplified modified Euclid's algorithm uses new initial conditions and polynomial computations to reduce hardware complexity, and thus, the implemented architecture consisting of 3r basic cells has the lowest hardware complexity compared with existing modified Euclid's and Berlekamp-Massey architectures. The Reed-Solomon decoder has been synthesized using the $0.18{\mu}m$ Samsung standard cell library and operates at 370MHz and its data rate supports up to 2.9Gbps. For the (255, 239, 8) RS code, the gate counts of the simplified modified Euclid's architecture and the whole decoder excluding FIFO memory are only 20,166 and 40,136, respectively. Therefore, the proposed decoder can reduce the total gate count at least 5% compared with the conventional DCME decoder.