• Title/Summary/Keyword: root characteristic

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Characteristic Impact Odorants of Changpo (Acorus calamus var. angustatus Bess) Root Essential Oil

  • Choi, Hyang-Sook
    • Food Science and Biotechnology
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    • v.14 no.4
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    • pp.450-455
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    • 2005
  • This study was conducted to determine firstly the composition of the essential oil from fresh changpo (Acorus calamus var. angustatus Bess) roots quantitatively and qualitatively by use of two internal standards, and secondly volatile compounds which are primarily responsible for the aroma of changpo roots. Simultaneous steam distillation and extraction method was used for essential oil extraction, and aroma extract dilution analysis (AEDA) and sniffing test by gas chromatography/olfactometry (GC/O) were used to detect the characteristic impact odorants. According to the instrumental analysis of changpo root essential oil, cis, trans-famesol (47.56 mg/kg of fresh wt), octanoic acid (23.73 mg/kg of fresh wt), trans-2-dodecenal (20.28 mg/kg of fresh wt) and trans, trans-farnesol (13.81 mg/kg of fresh wt) were the most abundant compounds. Geranyl acetate, trans-nerolidol and trans, trans-farnesyl acetate were evaluated as the characteristic impact odorants of changpo roots from results of AEDA and sniffing test. Especially, geranyl acetate was considered as the most similar odor component to changpo roots by organoleptic evaluation with GC/O.

Analyses of Shear Stress and Erosion Characteristic in a Vegetated Levee Revetment with Root Fiber Quantity (근모량에 따른 식생호안의 전단강도와 침식특성 분석)

  • Choi, Heung Sik;Lee, Woong Hee
    • Ecology and Resilient Infrastructure
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    • v.1 no.1
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    • pp.29-38
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    • 2014
  • This study analyzed shear stress and erosion characteristic of a vegetated levee embankment with root fiber quantity, which is an important factor for evaluating the stability of it. The averaged root fiber quantity in a vegetated levee revetment was measured by the sampler manufactured by this research. The Phragmites Japonica Steud which is somewhat dominant species in a vegetated levee embankment was selected as an experimental vegetation. As a result of experiment of each flow regime, the shear stress was increased while root fiber quantity was increased and the erosion rate was exponentially decreased as the root fiber quantity was increased. The erosion rate was exponentially decreased as the shear stress was increased which is shown that the increase of shear stress by root fiber quantity results in the increase of erosion resistance in a vegetated soil. The relationship between shear stress and erosion rate with root fiber quantity were analyzed and their regression equations were suggested with high determination coefficients. The hydraulic stability is governed by the increase of shear stress by root fiber quantity and the Froude number of flow characteristic in a vegetated levee revetment.

Dynamic Characteristic Study of Hingeless Blade Stiffness Reinforcement for Bearingless Rotor Whirl Tower Test (무베어링 로터 훨타워 시험을 위한 무힌지 블레이드 강성보강에 따른 동특성 연구)

  • Kim, Taejoo;Yun, Chulyong;Kee, Youngjoong;Kim, Seung-Ho;Jung, Sungnam
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.23 no.2
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    • pp.105-111
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    • 2013
  • Whirl tower test is conducted basically during helicopter rotor system development process. And for whirl tower test of rotor hub system, new design blade or existing blade which is remodeled for new rotor hub system is used. Because of simple shape and efficient aerodynamic characteristic, BO-105 helicopter blade is used for helicopter rotor hub development project widely. Originally BO-105 blade is used for hingeless hub system and blade root is used to flexure. So flap stiffness and lag stiffness at blade root area is relatively low compare with airfoil area. So, in order to apply the BO-105 blade to bearingless hub, blade root area have to be reinforced. And in this process, blade root area's section property is changed. In this paper, we suggest reinforcement method of BO-105 blade root area and study dynamic characteristic of bearingless rotor system with reinforcement BO-105 blade.

A Reduction Algorithm of Computational Amount using Adjustment the Not Uniform Interval and Distribution Characteristic of LSP (불균등 간격조절과 선형 스펙트럼 쌍 분포특성을 이용한 계산량 단축 알고리즘)

  • Ju, Sang-Gyu
    • Proceedings of the KAIS Fall Conference
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    • 2010.05a
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    • pp.261-264
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    • 2010
  • Fast algorithm is proposed by using mel scale and the distribution characteristic of LSP parameters, and is to reduce the computational amount. Computational amount means the calculating times of transformation from LPC coefficients to LSP parameters. Among conventional methods, the real root method is considerably simpler than other, but neverthless, it still suffer from its indeterministic computational time. Because the root searching is processed sequentially in frequency region. In this paper, the searching interval is arranged by using mel scale but not it is uniform and searching order is arranged by the distribution characteristic of LSP parameters that is most LSP papameters are occured in specific frequency region. In experimental results, computational amount of the proposed algorithm is reduced about 48.95% in average, but the transformed LSP parameters of the proposed method were the same as those of real root method.

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Studies on the Essential Oil of Korean Valerian Root (Valeriana fauriei var. dasycarpa Hara) (한국산 쥐오줌풀(Vaieriana fauriei var. dasycarpa Hara)의 정유성분에 관한 연구)

  • 김용태;박준영;김영회;김근수;장희진;권영주;이종철;최영현
    • Journal of the Korean Society of Tobacco Science
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    • v.14 no.1
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    • pp.66-78
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    • 1992
  • The essential oil of Korean valerian root ( Valeriana fauriei roar. dasycarpa Hara) was isolated by simultaneous distillation Sl extraction. The oil content of fresh root was 0.7% (wb) and that of dried root was 2.1 5 (db) and sensory analysis of the oil indicated sweet-balsamic, woody and floral characteristic aroma notes. The oil was fractionated into one hydrocarbon fraction and three oxygenated hydrocarbon fractions by using silica gel column chromatograpy. Each fraction was analyzed by capillary GC and GC-MS. Out of 81 characterized compounds, the major compounds were a-pinene, camphene, $\beta$-pinene, bornyl acetate, borneol , bornyl iso-valerate and sesquiphellandrene and the characteristic floral and woody aroma of neutral fraction of Korean valerian root could be due to be the presence of oxygenated compounds such as borneol, bornyl acetate, bornyl iso-valerate, p-ionone ana $\beta$-ionone epoxide. Comparing the yield of Korean valerian root with those from other origins reported, oil content of Korean valerian root was higher than those of European and Indian origins.

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Dynamic Characteristic Study of Hingeless Blade Stiffness Reinforcement for Bearingless Rotor Whirl Tower Test (무베어링 로터 훨타워 시험을 위한 무힌지 블레이드 강성보강에 따른 동특성 연구)

  • Kim, Tae-Joo;Yun, Chul-Yong;Kee, Young-Joong;Kim, Seung-Ho;Jung, Sung-Nam
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2012.04a
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    • pp.622-627
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    • 2012
  • During helicopter rotor system development process, whirl tower test is conducted basically. For conducting whirl tower test during bearingless hub development process, design new blade or using existing blade with repair or remodeling. Because simple shape and efficient aerodynamic characteristic, BO-105 blade is used for hub system development widely. Originally BO-105 blade is used for hingeless hub, ho flap stiffness and lag stiffness on blade root area is relatively low. So applying BO-105 blade to bearingless hub whirl tower test, root area have to be reinforce. In this process, blade root area's section property will be changed. In this paper, suggest reinforcement method of BO-105 blade root area and study dynamic characteristic of bearingless rotor system with reinforcement BO-105 blade.

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A calculation method of root loci band and its applications to robust control system design

  • Okuyama, Yoshifumi;Chen, Hong;Takemori, Fumiaki
    • 제어로봇시스템학회:학술대회논문집
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    • 1994.10a
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    • pp.350-353
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    • 1994
  • This paper presents a method to calculate the characteristic root areas and loci band of control systems with uncertainties. First, equations of boundary curves of root areas in the case of additive and multiplicative perturbation are derived. Then, an algorithm for the calculation of the array of closed curves is presented. When the upper bound of the absolute values of frequency responses for the uncertain part, is also frequency-dependent, the frequency-dependent, terms are included in the characteristic equation of the nominal system. This lead to the boundary equations of the root, areas for control systems with frequency-dependent uncertainty. Numerical examples of the control systems with multiplicative perturbations including frequency-dependent terms are presented to verify this calculation method. Finally, its applications to the design of robust control systems, e.g., passive adaptive control systems are also discussed.

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A Study on a Morphological Identification of Root of Angelica tenuissima, Ligusticum sinense and Ligusticum jeholense (고본(藁本)의 형태감별(形態鑑別)에 관한 연구(硏究))

  • Shin, Myoung-Soup;Kil, Ki-Jung;Lee, Young-Jong
    • The Korea Journal of Herbology
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    • v.20 no.4
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    • pp.33-39
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    • 2005
  • Objectives : Because Ligusticum sinense Root as well as those of Angelica tenuissima Root are sole as Gobon(藁本) in domestic markets, morphological characteristics of them are attempted to be distinguished. Methods : The slice of the tested material made by paraffin section technique was colored with Safranine Malachite Green contrast methods, and then observed and photographed by olymphus-BHT. Results : 1. Angelica tenuissima Root has considerable number of thick roots, but Chinese Ligusticum sinense Root and Ligusticum jeholense Root are composed of rhizomes mostly with small roots. 2. Intersection of rhizomes of Angelica tenuissima Root shows a 'V'-like arrangement of xylem vessel. 3. Chinese Ligusticum sinense Root and Ligusticum jeholense Root did not show the 'V'-like arrangement, and sliced fiber bundles were found in xylem. 4. There was no difference between Chinese Ligusticum sinense Root and Ligusticum jeholense Root. Conclusions : In conclusion, Angelica tenuissima Root, Chinese Ligusticum sinense Root, and Ligusticum jeholense Root show characteristic differences in internal forms, so that it is possible to distinguish them with optical microscope.

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The Computation Reduction Algorithm Independent of the Language for CELP Vocoders (각국 언어 특성에 독립적인 CELP 계열 보코더에서의 계산량 단축 알고리즘)

  • 민소연;배명진
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.2451-2454
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    • 2003
  • In this paper, we propose the computation reduction methods of LSP(Line spectrum pairs) transformation that is mainly used in CELP vocoders. In order to decrease the computational time in real root method the characteristic of four proposed algorithms is as the following. First, scheme to reduce the LSP transformation time uses met scale. Developed the second scheme is the control of searching order by the distribution characteristic of LSP parameters. Third, scheme to reduce the LSP transformation time uses voice characteristics. Developed the fourth scheme is the control of searching interval and order by the distribution characteristic of LSP parameters. As a result of searching time, computational amount, transformed LSP parameters, SNR, MOS test, waveform of synthesized speech, speech, spectrogram analysis, searching time reduced about 37.5%, 46.21%, 46.3%, 51.29% in average, computational amount is reduced about 44.76%, 49.44%, 47.03%, 57.40%. But the transformed LSP parameters of the proposed methods were the same as those of real root method.

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A study of clinical meaning and characteristic of Eight extra meridians(奇經八脈) (기경팔맥(奇經八脈)의 특징과 임상적 의의 연구)

  • Sohn, In-Chul
    • Korean Journal of Acupuncture
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    • v.25 no.1
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    • pp.39-50
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    • 2008
  • Objectives : The purpose of this study was to inquire clinical meaning and characteristic of Eight extra meridians(奇經八脈) by researching building and progression of Eight extra meridians theory. Results : As a result of research of building and progression of Eight extra meridians(奇經八脈) theory, we can regard that the origin of Eight extra meridians was based on lower Danjeon(丹田) which was the root of Primordial energy and the origin of the Twelve meridians and collaterals(十二經脈) was based on Middle energizer which was the root of Acquired energy. On this, we could know that Eight extra meridians and the Twelve meridians and collaterals are based on Primordial energy and Acquired energy and function of Eight extra meridians and the Twelve meridians and collaterals are complement each other. So, we can say that considering the Twelve meridians and collaterals means that is valued on Acquired energy clinically, and considering Eight extra meridians means that is valued on Primordial energy in health preserving method (養生).

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