• Title/Summary/Keyword: 억제대

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Studies on the suppression of Robinia pseudacacia sprouts by 2·4-D (2·4-D 처리(處理)에 의(依)한 아카시아 맹아억제(萠芽抑制)에 관(關)한 시험(試驗))

  • Son, Won Ha
    • Journal of Korean Society of Forest Science
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    • v.2 no.1
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    • pp.4-9
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    • 1962
  • (1) acacia 맹아(萠芽) 억제(抑制)에 대(對)한 2,4-D 살포(撒布)의 효과(効果)에 관여(關與)되는 조건(條件)을 시험(試驗)한바 다음과 같은 결과(結果)를 얻었다. a. 2,4-D 농도(濃度)${\cdots}{\cdots}{\cdots}$ 3,4,5 두식(斗式)의 범위에서는 3 두식(斗式) 최고농도(最高濃度)의 효과(効果)가 가장 크다. b. 살포시기(撒布時期) 5월(月) 상순(上旬)부터 7월(月) 하순(下旬)까지 순별(旬別) 시기(時期)를 분할(分割)하여 시험(試驗)한 즉 후기(後期)로 갈수록 효과(効果)가 컸다. c. 살포시간(撒布時間) 오전(午前) 10시(時), 오후(午後) 1시(時) 오후(午後) 4시(時) 중(中)에서 오후(午後) 1시(時) 가장 효과적(効果的)이었고 오전(午前) 10시(時) 가장 효과(効果)가 적었다. d. 살포(撒布) 계속년(年) 및 살포(撒布) 회수(回數) 계속 살포(撒布)할수록 효과(効果)는 누진적(累進的)이었다. (2) 다음과 같은 2,4-D 처리(處理)로 acacia 맹아(萠芽)는 억제(抑制) 됨을 알았다. a. 3두식(斗式) 농도(濃度)로 7월(月) 상순(上旬)~7월(月) 하순(下旬) 1년(年) 1차(次)씩 (1차(次)는 3일(日) 3회(回)) 계속 살포 3년간(年間)계속 살포(撒布). b. 3두식(斗式)로 오후(午後) 1시(時)에 5월(月) 상순(上旬)부터 1순(旬) 3회(回)씩 7월(月)까지 계속 살포(撒布).

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An Analysis on Combustion Instability in Solid Rocket Motor of 230mm Grade (230mm급 고체 추진기관의 연소불안정 거동 현상 분석)

  • Kwon, Tae-Hoon;Rho, Tae-Ho;Suh, Hyuk
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2009.05a
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    • pp.177-180
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    • 2009
  • A Possibility of combustion instability on longitudinal mode has a high level at large scale of L/D. Solid propellant has a metal particle and a grain of control to pressure oscillation. Solid rocket motor in slotted-tube grain controls pressure oscillation of longitudinal mode. If slot length is shot, pressure oscillation of longitudinal mode is amplified by cylinder part after middle phase of total burn time. A study has analyzed pressure oscillation of longitudinal mode at spectrum and acoustic modal analysis at pressure of result on static firing test.

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Residual Echo Suppression Based on Tracking Echo-Presence Uncertainty (Tracking Echo-Presence Uncertainty 기반의 잔여 반향 억제)

  • Park, Yun-Sik;Chang, Joon-Hyuk
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.10C
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    • pp.955-960
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    • 2009
  • In this paper, we propose a novel approach to residual echo suppression (RES) algorithm based on tracking echo-presence uncertainty (TEPU) to improve the performance of acoustic echo suppression (AES) in the frequency domain. In the proposed method, the ratio of the microphone input and the echo-suppressed output signal power is employed as the threshold value for the decision rule to estimate the echo-presence uncertainty applied to the RES filter. The proposed RES scheme estimates the echo presence uncertainty in each frequency bin and effectively reduces residual echo signal in a simple fashion. The performance of the proposed algorithm is evaluated by the objective test and yields better results compared with the conventional schemes.

A potential anticacner therapeutic strategy using light-emitting diode (자궁경부암세포 치료를 위한 발광다이오드의 응용)

  • Park, Chul Woo;Park, Kitae;Choi, Hojong;Choe, Se-woon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.05a
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    • pp.712-713
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    • 2017
  • Clinically applicable light emitting diode (LED) has been widely investigated because of relatively low heat generation, low cytotoxicity, and non-invasiveness compared to other therapeutic methods. Therefore, we investigated the therapeutic effects of several wavelengths of light emitting diode against human cervical cancer cells and analyzed the individual inhibitory effect for the cancer cell proliferation. In the experiment, prepared HeLa cells were exposed by red, green and blue light-emitting diode for 10 minutes each. Relatively short-wavelength light-emitting diode (blue) showed stronger therapeutic effects than relatively long-wavelength light-emitting diodes.

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Effects of Beverage Using Herbs on the Antimicrobial, Anticancer and Antiallergy Activities (약초 음료의 항균효과, 항암효과 및 알레르기 억제효과 검증)

  • Park, Eun-Mi;Ye, Eun-Ju;Kim, Soo-Jung;Kim, Sol-Ah;Bae, Man-jong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.7
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    • pp.953-958
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    • 2005
  • This study was conducted to investigate the effect of beverage (beverage HC and beverage PG) using herbs on antimicrobial activity, proliferation of hepatic cancer cell (Hep3B) lines and sarcoma 180 (S-180) and antiallergy, respectively. Beverage PG showed higher antimicrobial activity than beverage HC against Staphylococcus aureus and Pseudomonas aeruginosa. Beverage HC and PG showed the tumor suppressive effect in mice injected with S-180 cells. The growth-inhibitoy ratio against tumor cells were $66\%\;for\;10\%$ beverage HC, $61\%\;for\;10\%$ beverage PG. In an anti-cancer test using Hep3B cells, beverage PG showed higher anti-proliferating effect than beverage HC. Beverage PG showed growth-inhibitory effect of $69.2\%\;at\;100\%$ beverage PG. Beverage PG inhibited histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80. In conclusion, these results suggest that beverage using herbs have an antimicrobial activity, anti-proliferating effect against Hep3B cell and S-180 tumor and will be beneficial in treatment of allergic reaction.

Inhibitory Effects of Medicinal Plant Extracts and Identification of Inhibitory Substances (약용식물(藥用植物) 추출액(抽出液)의 발아억제효과(發芽抑制效果)와 관련화합물(關聯化合物) 탐색(探索))

  • Kim, K.U.;Lee, I.J.
    • Korean Journal of Weed Science
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    • v.9 no.2
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    • pp.154-167
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    • 1989
  • This study was conducted to determine the influence of various extracts from 21 medicinal plants including Bupleurm falcatum on the germination and growth of Lactuca sativa, Oryza native and E. crus-galli var. crus-galli, and the amount of their phenolic acids, fatty acids and organic acids, Water extract(5%) of all the medicinal plants, particularly Acorus gramineus, Cnidium officinale, Aconitum carmicheali, Bulpeurum falcatum, Zingiber officinale, Angelica gigas and Curcuma zeodaria inhibited over 90% of the lettuce seed germination and growth, indicating that medicinal plants contained the biologically active substances. The highest amount of phenolic compounds was observed in Prunus crmenica var, ansu(30.6013mg/g) followed by Aconitum ciliare(29.1008mg/g) and Cnidium officienale(27.2943mg/g) which inhibited markedly the germination of testing plants, showing the close relation of phenolic compounds to inhibitory effects. Cnidium officinale contained the highest amount of fatty acids(24.10mg/g) and organic acids(21.04mg/g) which may be partly related to inhibitory effects.

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Effect of Aqueous Extracts on the Callus Growth, Seed Germination, and Growth of Some Plants and Antibacterial Activity by Equisetum arvense L. (쇠뜨기(Equisetum arvense L.)의 수용추출액이 몇가지 식물의 캘러스 생장, 종자발아, 유묘생장 및 항균활성에 미치는 영향)

  • 이중호;이승엽
    • Korean Journal of Plant Resources
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    • v.12 no.1
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    • pp.20-26
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    • 1999
  • To investigate phytotoxic substances in Equisetum arvense, the aqueous extracts(25 and 8$0^{\circ}C$) or the freeze-drying matter from aqueous extracts($25^{\circ}C$) of E. arvense were tested at different concentrations for biological activities on callus induction and growth, seed germination, seedling growth and antibacterial function. Callus induction and growth of Oryza sativa and Brassica campestris ssp. pekinensis were inhibited by the aqueous extracts at 8$0^{\circ}C$ than at $25^{\circ}C$ and the higher concentrations. Callus growth of four receptor species was inhibited in order of Platycodon grandiflorum, Sesamum indicum, Brassica campestris ssp. pekinensis and Oryza sativa. Seed germination of Ο. sativa, S. indicum, and B. campestris ssp. pekinensis was not affected at low concentration, but it was proportionally inhibited by the higher concentrations. The greatest inhibition of seed germination was 28.3% compared to control, when 2,000$\mu\textrm{g}$/ml of freeze-drying matter was applied to B. campestris ssp. pekinensis. Shoot growth was stimulated by 500$\mu\textrm{g}$/ml of freeze-drying matter, but it was inhibited by the higher concentrations. Root growth was significantly inhibited compare to control at all concentrations. Antibacterial activity of freeze-drying matter didn't showed against Xantomonas oryzae and Eschrichia coli, but a small clear zone was formed by 500$\mu\textrm{g}$ of freeze-drying matter against Erwinia carotovora ssp. carotovora.

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Risk Factors of Delirium Among the Patients at a Surgical Intensive Care Unit (일 종합병원 외과계 중환자실 환자의 섬망 발생 요인)

  • Chun, You Kyoung;Park, Jeong Yun
    • Journal of Korean Critical Care Nursing
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    • v.10 no.3
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    • pp.31-40
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    • 2017
  • Purpose : This study examined the prevalence of delirium-related factors in a surgical intensive care unit (SICU). Methods : This retrospective study enrolled 73 patients who were admitted to an SICU from October 1, 2016 to March 20, 2017 and who had been hospitalized for more than 72 hours. Data was collected by reviewing electronic medical records. Results : Delirium occurred in 46 (63.0%) patients. Its related factors were age, education, mechanical ventilator, sleep, narcotics, physical restraint, and central line catheters. Conclusion : The results indicate that sleep and physical restraint are significant factors related to delirium occurrence. The results of this study can help in developing guidelines for the prevention of delirium.

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Noise Suppression Algorithm using Neural Network based Amplitude and Phase Spectrum (진폭 및 위상스펙트럼이 도입된 신경회로망에 의한 잡음억제 알고리즘)

  • Choi, Jae-Seung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.4
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    • pp.652-657
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    • 2009
  • This paper proposes an adaptive noise suppression system based on human auditory model to enhance speech signal that is degraded by various background noises. The proposed system detects voiced, unvoiced and silence sections for each frame and implements an adaptive auditory process, then reduces the noise speech signal using a neural network including amplitude component and phase component. Based on measuring signal-to-noise ratios, experiments confirm that the proposed system is effective for speech signal that is degraded by various noises.

Movement of Herbicide Pretilachlor in Plants and Soils (식물체(植物體) 및 토양중(土壤中)에 있어서 제초제(際草劑) Pretilachlor의 이동특성(移動特性))

  • Ma, Sang-Yong;Moon, Young-Hee;Ryang, Hwan-Seong
    • Applied Biological Chemistry
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    • v.30 no.4
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    • pp.351-356
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    • 1987
  • This study was conducted to investigate the absorption and translocation of pretilachlor [2-chloro-2, 6-diethyl-N-(n-propoxyethyl)-acetanilide] in plants and to evaluate the mobility in soil using the $^{14}C-or$ non-labelled compound in laboratory. Rice plant(Oryza sativa L.) was very tolerant to pretilachlor. Echinochloa crus-galli P. Beauv. was completely controlled by pretilachlor at 60g a.i./10a. At the 120g a.i./l0a, growth of Cyperus serotinus Rottb. and Sagittaria pygmaea Miq. was inhibited by 75% and 25%, respectively. The growth inhibition depended on absorbed amount of $^{14}C-pretilachlor$. The greatest concentration of $^{14}C$ was found in E. crus-galli, whereas the lowest was determined in rice plant. The rate of absorption and translocation in E. curs-galli was faster than in rice plan. Pretilachlor moved to 6cm deep in sandy clay loam, clay loam and loam soils, but to 10cm in sandy loam soil. In the soils herbicide-treated layer was found 0 to 2cm profile.

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