• Title/Summary/Keyword: Comparison time constant

Search Result 263, Processing Time 0.023 seconds

Comparison of In Vitro Digestion Kinetics of Cup-Plant and Alfalfa

  • Han, K.J.;Albrecht, K.A.;Mertens, D.R.;Kim, D.A.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.13 no.5
    • /
    • pp.641-644
    • /
    • 2000
  • In vitro true digestibility of cup-plant (Silphium perfoliatum L.) is higher than other alternative forages and comparative to alfalfa (Medicago sativa L.) even at the high neutral detergent fiber (NDF) concentration. This study was conducted to determine whether the digestion kinetic parameters of cup-plant could explain high in vitro true digestibility of cup-plant at the several NDF levels. Cup-plant and alfalfa were both collected in Arlington and Lancaster, Wisconsin to meet the NDF content within 40 to 50% range. The collected samples were incubated with rumen juice to investigate the digestion kinetics at 3, 6, 9, 14, 20, 28, 36, 48, and 72 h. Kinetics was estimated by the model $R=D_0\;e-k(t-L)+U$ where R is residue remaining at time t, and $D_0$ is digestible fraction, k is digestion rate constant, L is discrete lag time, and U is indigestible fraction. Parameters of the model were estimated by the direct nonlinear least squares (DNLS) method. Digestion rate and potential extent of digestion were not statistically different in either forage. However, alfalfa had shorter lag time (p<0.05). The indigestible fraction increased with maturation in alfalfa and in cup-plant (p<0.05). The ratio of indigestible fraction to acid detergent lignin (ADL) was higher in cup-plant than in alfalfa (p<0.05). From the results, alfalfa is probably digested more rapidly than cup-plant, however, cup-plant maintains higher digestibility with maturation due to a relatively slower increase of indigestible fraction in NDF.

Studies on the Syndiotactic Poly(vinyl alcohol) Polarizing Film -Preparation of Low Molecular Weight Syndiotactic Poly(vinyl alcohol)/Iodine Complex Film and Its Characterization- (교대배열 폴리비닐알코올 편광필름에 관한 연구 -저분자량 교대배열 폴리비닐알코올/요오드 복합체 필름의 제조와 특성 해석-)

  • 류원석;염정현;최진현;지병철;노태환
    • Polymer(Korea)
    • /
    • v.24 no.5
    • /
    • pp.713-720
    • /
    • 2000
  • A polymer/iodine complex film was prepared using syndiotactic poly(vinyl alcohol) (s-PVA) with number-average degree of polymerization of 900 and syndiotactic diad content of 63.1%. In comparison with atactic-PVA/iodine films, degree of polarization of the s-PVA/iodine film was improved up to over 99% although a lower transmittance was obtained. By soaking in iodine/potassium iodide aqueous solution of a lower iodine concentration and subsequent drawing by 4 times, s-PVA/iodine film of a higher transmittance and degree of polarization was produced. The degree of iodine desorption of the s-PVA/iodine film in water were very low. The crystallinity and the d-spacing and crystal size of (100) plane increased at the early stage of soaking time, however, remained constant or decreased slightly with increasing soaking time. In consequence, s-PVA/iodine complex formation took place mainly inside crystal region at the initial stage of soaking time, whereas it occurred outside crystal region or physical adsorption of iodine dominated after sufficient soaking.

  • PDF

Experiment for Clinical Application with Photodiode (Photodiode를 사용한 측정기의 임상응용을 위한 실험)

  • Kim, You-Hyun;Kwon, Soo-Il;Huh, Joon
    • Journal of radiological science and technology
    • /
    • v.19 no.2
    • /
    • pp.71-77
    • /
    • 1996
  • Studies were conducted to determine the clinical application of photodiode. We compared photodiode with ion-chamber as to change of tube potential, tube current, mAs and measured decreasing rate of penetration dose. When tube potential was changed from 60 kVp to 120 kVp, output of photodiode and ion-chamber were changed from 0.4 to 1.625, and 1.018 to 4.268, respectively. This was a good agreement to theory that $I=Kv^2it$(I is intensity, K is constant, v is tube potential, i is tube current, t is time). Characteristics for change of tube current and mAs were also a good agreement to theory. And comparison in decreasing rate of penetration dose was similar except above 6 cm in depth. Our results indicated that photodiode was a good instrument for relative measurement of radiation exposure, but we can not use the photodiode for absolute radiation dose.

  • PDF

Rheological Properties of Rehydrated Freeze Dried Instant Rice (동결건조 즉석미반의 리올로지적 성질)

  • Kim, Kwan-Yu;Lee, Shin-Young;Joo, Hyun-Kyu
    • Applied Biological Chemistry
    • /
    • v.32 no.4
    • /
    • pp.332-337
    • /
    • 1989
  • Rheological properties of rehydrated freeze dried instant rice were investigated in comparison with that of cooked rice. The time changes in reciprocal hardness of instant rice grains at various rehydration temperatures$(60{\sim}90^{\circ}C)$ could be expressed by the first order reaction rate equation regardless of rehydration temperature and reaction rate constant increased as the rehydration temperature increased. Activation energy for rehydrating instant rice was 6.1 kcal/g-mol. Analysis of compressive stress relaxation test showed that the viscoelastic properties of both rehydrated instant rice and cooked rice grains could be expressed by 6-elements generalized Maxwell model. Rehydrated instant rice revealed higher relaxation decay than that of cooked rice and showed the elastic property increased by increasing the rehydration temperature.

  • PDF

Comparison of Inguinal, Rectal, Axillary,and Tympanic Temperature in Newborns (신생아의 서혜, 직장, 액와, 고막 체온 측정 비교)

  • Koo, Hyun-Young;Son, Jung-Tae
    • Child Health Nursing Research
    • /
    • v.11 no.2
    • /
    • pp.203-210
    • /
    • 2005
  • Purpose: In order to identify the usability of inguinal temperature in a neonatal unit, this study was done to compare inguinal temperature of newborns with rectal, axillary, and tympanic temperatures. Method: Fifty-one normal newborns admitted to the nursery of a university affiliated hospital participated in the study. Tympanic temperatures were taken with a tympanic thermometer. Inguinal, rectal, and axillary temperatures were taken with glass mercury thermometers, and were recorded every 1 minute until the reading remained constant for 2 times. The data were analyzed using the SPSS program. Result: The measurement time for inguinal temperatures in newborns was significantly longer than that for rectal temperatures, but was shorter than that for axillary temperatures. The mean temperature for the newborn's inguinal site was lower than for rectal, axillary, and tympanic temperatures (the lower side), but wasn't different from tympanic temperature (the upper side). The inguinal temperature was significantly correlated with rectal, axillary, and tympanic temperature. The inguinal temperature was not different according to general characteristics of the newborn. Conclusion: These findings indicate that measurement of inguinal temperature is a useful alternative to rectal temperature.

  • PDF

DYNAMIC ANALYSIS OF A PERIODICALLY FORCED HOLLING-TYPE II TWO-PREY ONE-PREDATOR SYSTEM WITH IMPULSIVE CONTROL STRATEGIES

  • Kim, Hye-Kyung;Baek, Hun-Ki
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • v.14 no.4
    • /
    • pp.225-247
    • /
    • 2010
  • In this paper, we establish a two-competitive-prey and one-predator Holling type II system by introducing a proportional periodic impulsive harvesting for all species and a constant periodic releasing, or immigrating, for the predator at different fixed time. We show the boundedness of the system and find conditions for the local and global stabilities of two-prey-free periodic solutions by using Floquet theory for the impulsive differential equation, small amplitude perturbation skills and comparison techniques. Also, we prove that the system is permanent under some conditions and give sufficient conditions under which one of the two preys is extinct and the remaining two species are permanent. In addition, we take account of the system with seasonality as a periodic forcing term in the intrinsic growth rate of prey population and then find conditions for the stability of the two-prey-free periodic solutions and for the permanence of this system. We discuss the complex dynamical aspects of these systems via bifurcation diagrams.

A study on the inner flow fields characteristics of the Semi-active muffler (반능동형 머플러 내부의 유동장특성에 관한 연구)

  • Park Kyoung-Suk;Heo Hyung-Seok;Park Se-Jong;Son Sung-Man;Kim Dong-Hyun
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.23 no.3 s.180
    • /
    • pp.125-131
    • /
    • 2006
  • Recently air pollution has become an important issue. So, as tile number of vehicles increases, the noise pollution has become one of the most serious social issues nowadays. It is a muffler, which is one of the vehicle components. that has the hugest impact on the noise from the vehicle. And it also has a direct influence on the engine performance. So lately the research is proceeding on tile semi-active muffler which can control the back pressure variably by setting up the exhaust variable valve in the baffle to improve its internal structure. The inner parts of muffler which consist of a baffle, pipes and etc. appear to have the complicated turbulence phenomena by the pulsational wave of an unsteady state in the engine and by the structural characteristics of the inner parts. To analyze these phenomena, it is required to have an analysis of its constant quantity and quality. Therefore this study is to analyze with PIV measurement which can analyze the time and space variables, not with the point measurement method like former multi-point anemometer. It is to suggest proper design variables which need to make internal structure of the muffler improve though comparison between the passive type muffler and the semi-active muffler by fabricating a muffler which can be visualized.

Control of Layered Encryption for SVC Video Streaming (SVC 비디오 스트리밍을 위한 계층적 암호화 제어 기법)

  • Hwang, Jae-Hyung;Seo, Kwang-Deok;Jung, Soon-Heung
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.14 no.7
    • /
    • pp.1617-1625
    • /
    • 2010
  • Recently, the standardization of SVC technology which can provide adaptive video quality in diverse service environments has been completed. This paper proposes a layered encryption technique which takes into account the prioritized layer characteristics of SVC and control constant encryption complexity satisfying the target computational complexity. In particular, it analyzes the importance of NAL unit in the SVC video layer and suggests a method to apply appropriate encryption complexity proper for it. The effectiveness of the proposed method is proved through the comparison of time required for encryption and the reconstructed video quality using imperfect decryption key.

Spectrophotometric Determination of Chlorpheniramine Maleate with Methyl Orange (메칠오렌지에 의한 말레인산클로르페니라민의 분광광도 정량)

  • Chun, In-Koo
    • Journal of Pharmaceutical Investigation
    • /
    • v.16 no.4
    • /
    • pp.139-147
    • /
    • 1986
  • A singly charged methyl orange(MO) anion was found to be extracted with chlorpheniramine maleate(CPM) as a 1 : 1 complex in chloroform. Of various solvents, MO-chloroform system gave a yellow color for CPM, while in the absence of CPM, an organic phase showed almost no color. In this way, the spectrophotometric method was investigated for the determination of CPM by solvent extraction. The addition of alcoholic bolic acid solution to the solvent extract gave a higher color stability and transparency at least 5 days, but the extract alone lost its color intensity significantly. CPM is determined by measuring the absorbance of the extracts over a range of $1{\sim}7{\times}10^{-4}M\;(39{\sim}273\;{\mu}g/ml)$ in aqueous solution at 423 nm. The molar absorptivity was $2.26{\times}10^3\;l,\;mol^{-1},\;cm^{-1}$. The absorbance of the extract was constant in the range of pH $3.7{\sim}4.6$. This novel method was applied for the determination of CPM in artificial and commercial preparations in comparison with the analytical method of CPM tablets in K.P.IV. The results obtained showed that the former was better in accuracy and time consumption than the latter.

  • PDF

A Comparison Test of Eastern and Western Plow in Draft Resistance (우리나라 쟁기와 Plow의 산인저항의 관한 비교연구)

  • 최재갑
    • Magazine of the Korean Society of Agricultural Engineers
    • /
    • v.12 no.3
    • /
    • pp.2035-2042
    • /
    • 1970
  • Korean Janggi and Western plow to have developed for a long time in the east and west were tested and compared in their draft resistance. The charaderistic of Korean Janggi and plow to be able to make deep plowing, on of the most important factors influeneed the increased yield, were ofserved. The study was undertaken to obtain these basic factors' to device and construct the deep plowing Janggi. The results were as follow; 1. The draft resistance of Korean Janggi far less than that of plow and on the dry field, the influence of soil moisture contant to the draft resistance was larger in the Korean Janggi than in the western plow, but on the rice paddy, there was not differences between them. 2. The plow was more stable than that of Janggi in their operation. 3. The relation ship between the specific draft resistance and plowing depth was shown bygthe carved equation. $$K=Ax+\frac{B}{x}+C$$(K ; specific draft restance, x; plowing depth) A, B, C; Constant controled by soil and instrument factor) 4. Minimam values of the specific draft resistance were as follow; a. On the dry field; Korean Janggi; x = $8{\sim}14cm$ $4K=280{\sim}330gr/cm^2$$ Westean plow; x=$10{\sim}12cm$ $$K=480{\sim}490gr/cm^2$$ 6. On the rice paddy; Korean Janggi; x=$8{\sim}12cm$ $$K=255{\sim}280gr/cm^2$ Western plow; x=$7{\sim}10cm$ $$K=415{\sim}420grc/m^2$$

  • PDF