• Journal of Life Science
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• v.23 no.8
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• pp.1004-1009
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• 2013

The biochemical compositions and nutritive values of six species of seaweeds were analyzed to determine their applicability in functional foods or ingredients. The biochemical compositions (moisture, ash, protein, lipid, and dietary fiber) and fatty acid contents were determined for the following seaweed extracts: Phaeophyceae (Laminaria japonica, Hizikia fusiformis, and Undaria pinnatifida), Rhodophyceae (Porphyra tenera and Gracilaria verrucosa), and Chlorophyceae (Ulva lactuca). The moisture content (% dry weight) ranged from 11.47% to 13.94%, ash from 19.15% to 26.50%, protein from 5.08% to 15.44%, lipid from 2.75% to 4.43%, and dietary fiber from 36.84% to 52.98%. C14:0, C16:0, C18:0, C16:1, C18: 1n-3, C18:2n-6, C18:3n-6, C20:4n-6, and C20:5n-3 represented the predominant proportions of fatty acids. Interestingly, docosahexaenoic acid (C22:6n-3, DHA) was either not found or only detected in trace amounts in the analyzed seaweeds. The levels of n-3 fatty acid were higher than other polyunsaturated fatty acids, and the n-6/n-3 ratio was very low. These results indicate that seaweed inhabiting Korean coastal areas will be beneficial to human health.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1996.11a
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• pp.134-139
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• 1996

The electron energy distributions function were analysed in sulphur hexaflouride at E/N : 500~800(Td) for a case of non-equilibrium ion in the mean electron energy. This paper describes the electron transport characteristics in SF$_{6}$ gas calculated for range of E/N values from 150~800(Td) by the Monte Carlo simulation and Boltzmann equation method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters. The results gained that the value of an electron swarm parameter such as the electron drift velocity, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients agree with the experimental and theoretical for a range of E/N. The properties of electron avalanches in an electron energy non-equilibrium region.n.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.8
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• pp.1163-1172
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• 2001

The two dimensional problem of a layered tribological system(TiN/Steel) containing a vertical surface breaking crack and subject to rolling contact is considered in this study. Using finite elements and stress extrapolation method, a series of preliminary models are developed. Preliminary results indicate that the extrapolation technique is valid to determine Modes I and II stress intensity factors for cracks. In the case of TiN/Steel medium, KI and KII were determined for variations in crack length, layer thickness, and load location. The results show that KII reaches maximum values when the contact is adjacent to the crack where Mode I stresses are compressive. KII values decrease with decreased crack length and significantly decrease for reduced layer thickness.

• Kyungpook Mathematical Journal
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• v.55 no.3
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• pp.641-652
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• 2015

In this paper we study the problem of normal families of meromorphic functions concerning shared values. Let F be a family of meromorphic functions in the plane domain $D{\subseteq}{\mathbb{C}}$ and n, k be two positive integers such that $n{\geq}k+1$, and let a, b be two finite complex constants such that $a{\neq}0$. Suppose that (1) $f+a(f^{(k)})^n$ and $g+a(g^{(k)})^n$ share b in D for every pair of functions f, $g{\in}F$; (2) All zeros of f have multiplicity at least k + 2 and all poles of f have multiplicity at least 2 for each $f{\in}F$ in D; (3) Zeros of $f^{(k)}(z)$ are not the b points of f(z) for each $f{\in}F$ in D. Then F is normal in D. And some examples are provided to show the result is sharp.

• Journal of the Korean Ceramic Society
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• v.26 no.2
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• pp.201-209
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• 1989

Fine Si-Al-OH coprecipitate powders were prepared from Si- and Al-alkoxides by the hydrolysis method. $\beta$-Sialon powder was obtained from prepared Si-Al-OH coprecipitate by the simultaneous reduction and nitridation method. The syntehsized Sialon powder was pressureless sintered at 175$0^{\circ}C$ for 90 min in N2 atmosphere. The characterization of the Sialon powder was performed with XRD, BET, SEM, TEM and particle size analysis. The sinterability and mechanical properties of sintered bodies were investigated in terms of relative density, M.O.R., fracture toughness, hardness and the morphology of microstructure. The highest values of their mechanical properties were obtained for the $\beta$-Sialon ceramics at Z=1 and those values are as follows : M.O.R., KIC and HV of $\beta$-Sialon ceramics(Z=1) are 499.1 MPa, 5.9MN/m3/2 and 18.7GPa, respectively.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.13 no.2
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• pp.227-227
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• 1999

The electron energy distributions function were analysed in sulphur hexaflouride at E/N : 500~800(Td) for a case of non-equilibrium region in the mean electron energy. This paper describes the electron transport characteristics in $SF_6$ gas calculated for range of E/N values from 150~800(Td) by the Monte Carlo simulation and Boltzmann equation method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters. The results gained that the value of ane1ctron swarm parameter such as the e1ectron drift velocity, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients agree with the experimental and theoretical for a range of E/N. The properties of electron avalanches in an electron energy non-equilibrium region.

• Journal of the Korean Chemical Society
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• v.23 no.1
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• pp.1-6
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• 1979

The dipole moments for square planar and tetrahedral $[M(II)N_2S_2]$ type complexes are calculated, using the expansion method for spherical harmonics [M(II) = Co(II), Ni(II), Cu(II) or Zn(II)]. The calculated values of the dipole moments for these complexes are in the range of the experimental values. The possible structures for these complexes in benzene solution are discussed on the basis of the calculated dipole moments and the the magnetic properties.

• Journal of Biosystems Engineering
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• v.21 no.1
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• pp.84-93
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• 1996

Several paraffins(CnH2n +2) can be used as the thermal energy storage medium because of their large amount of latent heat and their flexibility of phase change temperature. But they have not been used in the thermal energy storage system because their long term stability have not been verified. Paraffins(CnH2n+2) which the values of n are 23, 24, 26 and 28 were selected for this experimental research. And this research was peformed to apply them to the practical systems. The results were summarized as follows. (1) The increase of phase change cycles had no effect on their phase change temperatures. (2) According as the values of n increased from 23 to 28, the specific heats of paraffins(CnH2n+2) increased, and were in the range of 0.47 0.75 ㎉/$kg^circ C$. (3) Thermal conductivities of them were in the range of 0.14 0.17 W/$m^circ C$. and specific gravities of them were in the range of 765800 kg/m3. (4) The density of paraffins was in the range of 765 800 kg/$m^circ C$ , and the density of solid phase was larger than that of liquid phase. (5) When the number of phase change cycles was 1, 500 cycles, the latent heat of paraffins was 90% of the initial value.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4361-4365
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• 2011

The nucleophilic substitution reactions of bis(N,N-dimethylamino) phosphinic chloride (3) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at $65.0^{\circ}C$. The anilinolysis rate of 3 is rather slow to be rationalized by the conventional stereoelectronic effects. The magnitudes of ${\rho}_X$ (= -6.42) and ${\beta}_X$ (= 2.27) values are exceptionally great. The deuterium kinetic isotope effects (DKIEs; $k_H/k_D$) are secondary inverse ($k_H/k_D$ = 0.69-0.96). A concerted $S_N2$ mechanism involving a backside attack is proposed on the basis of secondary inverse DKIEs and the variation trend of the $k_H/k_D$ values with X. The anilinolyses of six phosphinic chlorides in MeCN are briefly reviewed by means of DKIEs, steric effects of the two ligands, positive charge of the reaction center phosphorus atom, and selectivity parameters to obtain systematic information on phosphoryl transfer reaction mechanism.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.101-107
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• 2011

This study aimed to determine dose-response (DR) curve of avian influenza (AI) virus to predict the probability of illness or adverse health effects that may result from exposure to a pathogenic microorganism in a quantitative microbial risk assessment. To determine the parametric DR relationship of several strains of AI virus, 7 feeding trial data sets challenging humans (5 sets) and chickens (2 sets) for strains of H3N2 (4 sets), H5N1 (2 sets) and H1N1 (1 set) from the published literatures. Except for one data set (study with intra-tracheal inoculation for data set no. 6), all were obtained from the studies with intranasal inoculation. The data were analyzed using three types of DR model as the basis of heterogeneity in infectivity of AI strains in humans and chickens: exponential, beta-binomial and beta-Poisson. We fitted to the data using maximum likelihood estimation to get the parameter estimates of each model. The alpha and beta values of the beta-Poisson DR model ranged 0.06-0.19 and 1.7-48.8, respectively for H3N2 strain. Corresponding values for H5N1 ranged 0.464-0.563 and 97.3-99.4, respectively. For H1N1 the parameter values were 0.103 and 12.7, respectively. Using the exponential model, r (infectivity parameter) ranged from $1.6{\times}10^{-8}$ to $1.2{\times}10^{-5}$ for H3N2 and from $7.5{\times}10^{-3}$ to $4.0{\times}10^{-2}$ for H5N1, while the value was $1.6{\times}10^{-8}$ for H1N1. The beta-Poisson DR model provided the best fit to five of 7 data sets tested, and the estimated parameter values in betabinomial model were very close to those of beta-Poisson. Our study indicated that beta-binomial or beta-Poisson model could be the choice for DR modeling of AI, even though DR relationship varied depending on the virus strains studied, as indicated in prior studies. Further DR modeling should be conducted to quantify the differences among AI virus strains.