• Title/Summary/Keyword: Relative alpha

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The Parametric Sensitivity Analyses of linear System Relative to the Characteristic Ratios of Coefficient(II) : K-Polynomial Case (계수의 특성비에 대한 선형계의 파라미터적 감도해석(II) : K-다항식의 경우)

  • 김영철;김근식
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.4
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    • pp.295-303
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    • 2004
  • Previously it has been shown that the all pole systems resulting good time responses can be characterized by so called K-polynomial. The polynomial is defined in terms of the principal characteristic ratio $\alpha_1$ and the generalized time constant $\tau$ . In this paper, Part II presents several sensitivity analyses of such systems with respect to $\alpha_1$ and $\tau$ changes. We first deal with the root sensitivity to the perturbation of $\alpha_1$ . By way of determining the unnormalized function sensitivity, both time response sensitivity and frequency response sensitivity are derived. Finally, the root sensitivity relative to $\tau$ change is also analyzed. These results provide some useful insight and background theory when we select of and l to compose a reference model of which denominator is a K-polynomial, which is illustrated by examples.

Effect of Maternal Dietary $\omega$3 and $\omega$6 Polyunsaturated Fatty Acids on the Fatty Acid Composition of the Second Generation Rat Brain (어미 쥐의 $\omega$3계 및 $\omega$6계 지방산 식이가 제2세대 쥐의 뇌조직 지방산 성분에 미치는 영향)

  • 김미경
    • Journal of Nutrition and Health
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    • v.26 no.6
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    • pp.661-671
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    • 1993
  • The change in fatty acid composition in brain tissue of the second generation rats(Sprague-Dawley strain) was studied using four different fat diets(Corn oil=CO, Soybean oil=SO, Perilla oil=PO, Fish oil=FO, 10% by Wt). The experimental diets were started from pregnancy in four different groups, each consisting of 9 rats. The seound generation rats were fed the same diet as their mothers. Animals were anesthetized with ether at 0, 3, 9 & 16 weeks of age. Whole brains were dissected out, brain tissues were, then, homogenized and lipids were extracted from brain tissues. The fatty acid compositions were measured after methylation by gas-liquid chromatography at 0, 3, 9 and 16 weeks of age of offspring. The changes in the relative concentrations of polyunsaturated fatty acids(PUFA) or more specifically docosahexaenoic acid(22 : 6, $\omega$3, DHA), the major $\omega$3 fatty acid component in rat brain at different age were similar to changes in the amount of DNA in brain tissue showing the maximum value during the lactation. The changes in saturated fatty acid(SFA) content showed a contrasting patten to those of PUFA, while monounsaturated fatty acid(MUFA) increased steadily throughout the experimental period. At birth, the relative concentrations of $\omega$3 series fatty acids the relative concentrations of PUFA, MUFA and SFA converged to very similar values respectively regardless of the dietary fatty acid compositions. In brain tissue, it is of value to note that while changes in relative concentrations of linoleic acid (18 : 2, $\omega$6, LA) and arachidonic acid(20 : 4, $\omega$6, AA) showed a precursor-product-like relationship, $\alpha$-linolenic acid(18 : 3, $\omega$3, $\alpha$-LnA) and DHA showed a different pattern. Even when the $\omega$3 fatty acid content in very low in maternal diet(CO), the second generation rat brain tissues appeared to secure DHA content, suggesting an essential role of this fatty acid in the brain. The fact that a large amount of $\alpha$-LnA in the maternal diet did not have a significant effect on the second generation rat brain $\alpha$-LnA content, indicated that DHA seemed essential component for the brain development in our experimental condition. In all groups, the relative content of $\alpha$-LnA in the brain tissues remained relatively constant throughout the experimental period at the very low level. The study of the specific concentrations and essential role(s) of DHA in each parts of brain tissue is needed in more details.

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A GAUSSIAN WHITE NOISE GENERATOR AND ITS APPLICATION TO THE FLUCTUATION-DISSIPATION FORMULA

  • Moon, Byung-Soo
    • Journal of applied mathematics & informatics
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    • v.15 no.1_2
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    • pp.363-375
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    • 2004
  • In this paper, We show that the bandpass random signals of the form ∑$_{\alpha}$$\alpha$$_{\alpha}$ a Sin(2$\pi$f$_{\alpha}$t + b$_{\alpha}$) where a$_{\alpha}$ being a random number in [0,1], f$_{\alpha}$ a random integer in a given frequency band, and b$_{\alpha}$ a random number in [0, 2$\pi$], generate Gaussian white noise signals and hence they are adequate for simulating Continuous Markov processes. We apply the result to the fluctuation-dissipation formula for the Johnson noise and show that the probability distribution for the long term average of the power of the Johnson noise is a X$^2$ distribution and that the relative error of the long term average is (equation omitted) where N is the number of blocks used in the average.error of the long term average is (equation omitted) where N is the number of blocks used in the average.

Highly Selective and Simple Zero and First Order Derivative Spectrophotometric Determination of Palladium by Using α-Benzilmonoxime in Triton X-100 Micellar Solution

  • Eskandari, Habibollah;Karkaragh, Gholamhassan Imanzadeh
    • Bulletin of the Korean Chemical Society
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    • v.24 no.12
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    • pp.1731-1736
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    • 2003
  • The reaction of ${\alpha}$-Benzilmonoxime with palladium(II) produces a green complex in triton X-100 micellar media. Palladium has been determined using zero and first derivative spectrophotometric methods. The absorbances of Pd(II)- ${\alpha}$--benzilmonoxime complex at 441.8 and 677.0 nm in 0.10 M perchloric acid solution were monitored and linear working ranges of 0.3-12.0 and 0.7-20 ${\mu}$g mL$^{-1}$ with detection limits of 0.07 and 0.10 ${\mu}$g $mL^-1$ were obtained, respectively. Also, recoveries in the range of 92.8 to 100.1% and relative standard deviations in the range of 0.4 to 7.1% were obtained. First derivative spectrophotometry has also been applied for palladium determination under the optimum condition. The linear dynamic range of 0.2-24.0 ${\mu}$g $mL^{-1}$ palladium with relative standard deviations of 0.6-6.9% and recoveries in the range of 94.9-102.5% has been obtained by first derivative spectrophotometry. The method shows high selectivity because of the high concentration of acid used, which prevents formation of complexes of ${\alpha}$--benzilmonoxime with the other cations. The palladium complex formed was stable at least one day. The method was successfully applied to the determination of palladium in some synthetic palladium alloys and palladium-charcoal powder.

Effects of Cranial Electrotherapy Stimulation on Electrocephalogram

  • Lee, Jeongwoo;Lee, Hyejein;Park, Woongsik
    • Journal of International Academy of Physical Therapy Research
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    • v.10 no.1
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    • pp.1687-1694
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    • 2019
  • Background: Although cranial electrotherapy stimulation (CES) is reported to have positive effects on mental functions such as depression and sleep improvement, detailed studies regarding awakening, attention and concentration among brain waves reflecting brain activity are lacking. Objective: To examine the effects of cranial electrotherapy stimulation (CES) on various electroencephalograms (EEGs) reflecting brain activities. Design: Randomized controlled clinical trial (single blind) Methods: This study selected 30 healthy adult women in their 20s who volunteered for this experiment. A total of 30 subjects were randomly assigned to three groups (Sham group, 0.5 Hz CES group, and 100 Hz CES group). EEGs were measured before and after the single CES, and the results were compared and analyzed. Results: The relative theta, alpha, and gamma waves indicated no significant differences in the interaction effects between time and group. The relative fast alpha wave only showed significant differences in the interaction effects between time and group in P4. The relative slow beta wave only indicated statistically significant differences in the interaction effects between time and group in T3 and T4. The relative mid and fast beta waves showed statistically significant differences in the interaction effects between time and group in all areas. Conclusions: These results suggest that a CES of 0.5 Hz awakens consciousness and has a positive influence on brain activity, while a CES of 100 Hz has a positive influence on thinking activity accompanying mental load during concentrating on one subject.

Effect of Change in Degrees of Inclination during Treadmill Gait Training on EEG of Stroke Patients (경사도 각도에 따른 트레드밀 보행훈련 시 뇌졸중 환자의 뇌파에 미치는 영향)

  • Sun-Min Kim;Dong-Hoon Kim;Sang-Hun Jang
    • PNF and Movement
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    • v.22 no.1
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    • pp.139-149
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    • 2024
  • Purpose: This study aimed to investigate the effects of gradually increasing treadmill inclination on the electroencephalogram (EEG) of stroke patients during gait training. Methods: Three stroke patients who were diagnosed with stroke within six months and capable of walking on a treadmill were selected as subjects. EEG electrodes were attached at Fp1, Fp2, F3, F4, C3, C4, P3, and P4 positions of the cerebral hemispheres using the International 10-20 system. The intervention involved walking for 2 minutes each at 0 degrees, 15 degrees, and 30 degrees inclination on the treadmill while focusing on a target point located in front during the treadmill gait training. The EEG (Smartingmobi, Serbia) generated when the treadmill gradient gradually increased was measured. In addition, relative alpha and relative beta waves were visualized through the Brain mapping program in the TeleScan program to assess the changes in each brain region for the activity of the EEG. Results: The relative alpha wave value decreased as treadmill inclination increased, while the relative beta wave value increased. Conclusion: Gradually increasing the inclination during treadmill gait training appears to be a crucial parameter for increasing the brain activity levels of stroke patients.

Substituent Effect in Photochemistry of ${\beta}-Ethoxy-{\alpha}-halopropiophenones$

  • Cho, Sung-Su;Park, Bong-Ser
    • Journal of Photoscience
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    • v.12 no.2
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    • pp.83-85
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    • 2005
  • Photochemical reactivities of ${\beta}-ethoxypropiophenones$ are changed dramatically by putting a halogen at a position to the carbonyl functionality. ${\alpha}-Bromo-{\beta}-ethoxypropiophenone$ gives C-Br bond cleavage products solely, but ${\alpha}-chloro-{\beta}-ethoxypropiophenone$ forms mainly the Yang photocyclization products upon irradiation. The different reactivities of two compounds can be explained by relative rates of C-X bond cleavage and a-hydrogen abstraction.

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A NOTE ON THE DISPERSION RELATION OF THE MODIFIED BOUSSINSQ EQUATIONS

  • Cho, Yong-Sik;Lee, Chang-hoon
    • Water Engineering Research
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    • v.1 no.4
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    • pp.293-298
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    • 2000
  • Optimal values of $\alpha$ characterizing the linear dispersion property in the modified Boussinesq equations are determined by minimizing the combined relative errors of the phase and group velocities. The value of $\alpha$ is fixed in previous studies, whereas it is varying in the present study. The phase and group velocities are calculated by using variable $\alpha$ and compared to those of the linear Stokes wave theory and previous studies. It is found that the present study produces the best match to the linear Stokes theory.

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Functional Properties of $\alpha$-Lactalbumin Separated from Bovine Whey (우우 유청으로부터 분리한 $\alpha$-락트알부민의 기능적 특성)

  • 홍윤호
    • Food Science of Animal Resources
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    • v.18 no.1
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    • pp.9-18
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    • 1998
  • This study was performed to obtain a large quantity of $\alpha$-lactalbumin ($\alpha$-LA) from milk by an improved separation and purification method. Functional properties-solubility viscosity, emulsifying activity, foamability surface hydrophobicity and gelation-of the purified $\alpha$-LA were investigated, $\alpha$-LA was purified in a large quantity by DEAE-Sephacel chromatography using 0.15M NaCl in 20mM Tris-HCl buffer(pH 7.2), as an eluent. The yield and purity of the purified $\alpha$-LA were 23.6%, 92.5%, respect-ively. The solubility viscosity and emulsifying activity of the purified $\alpha$-LA were 92.2$\pm$2% 3.46$\pm$0.19 cP and 345$\pm$5.0m^2$-/g respecively. The foamability of $\alpha$ -LA was 762 after 5min whipping which was lower than that of WPC and showed decreasing tendency with whipping time. The relative surface hydrophobicity of the $\alpha$-LA was formed when a 10% $\alpha$-LA solution containing 100mM NaCl and 20 mM $CaCl_2$ was heated at 92$^{\circ}C$for 40min. The $\alpha$-LA gel showed 31.5 as hardness and showed low springiness and cohesiveness.

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A Study on the Indoor Temperature effects on Neuro-energy (실내 온도가 뉴로에너지에 미치는 영향에 관한 연구)

  • Kim, Jung-Min;Kim, Myung-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.4
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    • pp.2436-2442
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    • 2014
  • In this study, EEG, HRV, and Vibra image were compared and analyzed in the environmental test room due to variation of temperature. The condition of the environmental test room was in relative humidity 50[RH%], air current speed 0.02[m/s] and illuminance 1000[lux] with setting up different temperatures from $18[^{\circ}C]$ to $31[^{\circ}C]$. At temperature $25[^{\circ}C]$, relative $M{\alpha}$ wave, relative $M{\beta}$ wave, $\frac{SMR}{\theta}$, and SDNN were revitalized, and both sides ${\alpha}$ wave asymmetry index $A_2$, HRT, stress index, and fatigue degree were decreased. Therefore, it was found that temperature $25[^{\circ}C]$ effects to increase the Neuro-energy like amenity, productivity, and concentration.