• Honam Mathematical Journal
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• v.32 no.1
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• pp.167-176
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• 2010

Let (B, $\check{g}$) and (N, $\hat{g}$) be Einstein manifolds. Then, we get a complete (necessary and sufficient) condition for the warped product manifold $B\;{\times}_f\;N\;:=\;(B\;{\times}\;N,\;\check{g}\;+\;f{\hat{g}}$) to be Einstein, and obtain a complete condition for the Einstein warped product manifold $B\;{\times}_f\;N$ to be weakly stable. Moreover, we get a complete condition for the map i : ($B,\;\check{g})\;{\times}\;(N,\;\hat{g})\;{\rightarrow}\;B\;{\times}_f\;N$, which is the identity map as a map, to be harmonic. Under the assumption that i is harmonic, we obtain a complete condition for $B\;{\times}_f\;N$ to be Einstein.

• Journal of Nutrition and Health
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• v.26 no.7
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• pp.867-886
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• 1993

Vitamin B-6 status parameters of mothers were assessed in relation to th condition of the infant at birth and during the neonatal period. Parameters were assessed at birth and then weekly in 18 mother-infant pairs during the neonatal period ; mothers were supplemented postnatally with 2 or 27 mg PN-HCI/d. Vitamin B-6 inadequacy in the 2mg supplemented group was suggested by the vitamin status parameters. Mothers whose infants had unsatisfactory Apgar scores at 5min after birth(<7) had lower vitamin B-6 status parameters than mothers whose infants were scored satisfactory. Also, infants who scored unsatisfactory at birth and whose mothers were supplemented with the low level of PN had significantly lower vitamin B-6 status parameters at 7 days of age than infants who scored satisfactory. Infants scored unsatisfactory showed some beneficial effects in both vitamin B-6 status and growth associated with the higher level of maternal postnatal vitamin B-6 supplement. In summary, the mother's prenatal and postnatal vitamin B-6 intake were significantly related to the condition of her infant at birth and during the neonatal period, respectively.

• Journal of Astronomy and Space Sciences
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• v.27 no.4
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• pp.329-335
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• 2010

We investigate the sources of the variation of the high-latitude thermospheric neutral mass density depending on the interplanetary magnetic field (IMF) conditions. For this purpose, we have carried out the National Center for Atmospheric Research Thermosphere-Ionosphere Electrodynamics General Circulation Model (NCAR-TIEGCM) simulations for various IMF conditions under summer condition in the southern hemisphere. The NCAR-TIEGCM is combined with a new empirical model that provides a forcing to the thermosphere in high latitudes. The difference of the high-latitude thermospheric neutral mass density (subtraction of the values for zero IMF condition from the values for non-zero IMF conditions) shows a dependence on the IMF condition: For negative $B_y$ condition, there are significantly enhanced difference densities in the dusk sector and around midnight. Under the positive-$B_y$ condition, there is a decrease in the early morning hours including the dawn side poleward of $-70^{\circ}$. For negative $B_z$, the difference of the thermospheric densities shows a strong enhancement in the cusp region and around midnight, but decreases in the dawn sector. In the dusk sector, those values are relatively larger than those in the dawn sector. The density difference under positive-$B_z$ condition shows decreases generally. The density difference is more significant under negative-$B_z$ condition than under positive-$B_z$ condition. The dependence of the density difference on the IMF conditions in high latitudes, especially, in the dawn and dusk sectors can be explained by the effect of thermospheric winds that are associated with the ionospheric convection and vary following the direction of the IMF. In auroral and cusp regions, heating of thermosphere by ionospheric currents and/or auroral particle precipitation can be also the source of the dependence of the density difference on the IMF conditions.

• Journal of the Korean Wood Science and Technology
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• v.44 no.2
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• pp.191-203
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• 2016

To investigate the dynamic sorptive and hygroexpansive behaviors of wood by different cyclic hygrothermal changing effects, poplar (populus euramericana Cv.) specimens, were exposed to dynamic sorption processes where relative humidity (RH) and temperature changed simultaneously in sinusoidal waves at 75-45% and $5-35^{\circ}C$ (condition A) and where RH changed sinusoidally at 75-45% but temperature was controlled at $20^{\circ}C$ (condition B), both for three cyclic periods of 1, 6, and 24 h. Moisture and dimensional changes measured during the cycling gave the following results: Moisture and transverse dimensional changes were generally sinusoidal. Moisture and dimensional amplitude increased with increasing cyclic period but all were lower for thicker specimens. The amplitude ratio of condition A to condition B ranged from 1.0 to 1.6 with the maximum value of 1.57 occurring at the shortest cyclic period, not as much as expected. T/R increased as cyclic period increased or specimen thickness decreased. T/R from condition B was weaker than that from condition A. Sorption and swelling hysteresis existed in both conditions. Sorption hysteresis was negatively related to cyclic period but in positive correlation with specimen thickness. Sorption hysteresis was found more obvious in condition B, while moisture sorption coefficient and humidity expansion coefficient showed the opposite results.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.5
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• pp.713-722
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• 2004

This study examined the effects of two kinds of functional sun hats through a head-manikin test and a climatic chamber trial for farm workers in summer. Experiment was composed of four conditions. The first condition was the condition without any hat (Control). The second was the condition with a sun hat on the market (Hat A). The third was the condition with a functional sun hat made of reflective fabric (Hat B). The last was the condition with a functional sun hat having a ventilating structure as well as reflective fabric (Hat C). For the subjects in the climatic chamber trials, 12 healthy males volunteered. Air temperature, relative humidity and globe temperature in the chamber was maintained at $33{\pm}0.5^{\circ}C,\;65{\pm}5%RH\;and\;39{\pm}1^{\circ}C\;(WBGT\;33^{\circ}C)$. Subjects did a simulated red pepper-work (50-min work and 10-min rest, twice repetition) for 120 min. As the result of head-manikin test, the surface temperature on middle of back-neck was the lowest in Hat B of four conditions and the surface temperature on top of head was the lowest in Hat C. As the result of climatic chamber trials, there were apparent differences between with (Hat A, Hat B, Hat C) and without a sun hat (Control). In rectal temperature ($T_{re}$), mean skin temperature ($\={T}_{sk}$), heart rate (HR), total sweat rate (TSR), The physiological heat strain was less in the condition with hats than in the condition without a sun hat. As the increasing rate in Tre, Hat B is the most effective hat for alleviation heat strain. As the subjective responses, Hat B was the most effective hat for thermal comfort even though the difference was not significant. Hat C was less effective than Hat B and the reason might be the increase of weight due to inserting the ventilating structure.

• International journal of advanced smart convergence
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• v.3 no.1
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• pp.20-24
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• 2014

To compare body signal, was designed the F-B function system on the body movement for the comfortable state. To detect subject of the normal state, was decided on the base of physical signal in the body movement. There are to detect the condition of Vision, Vestibular, Somatosensory and CNS. Vision condition was verified a variation of greater average (Vi-${\Phi}_{AVG-AVG}$) was presented slightly greater at $17.424{\pm}9.65$ unit. Vestibular condition was identified a variation of slightly greater average (Ve-${\Phi}_{AVG-AVG}$) was presented at $9.068{\pm}1.478$ unit. Somatosensory condition was checked a variation of smaller average (So-${\Phi}_{AVG-AVG}$) was presented slightly smaller at $2.79{\pm}0.419$ unit. CNS condition was confirmed a variation of diminutive smaller average (C-${\Phi}_{AVG-AVG}$) was presented slightly larger at $0.557{\pm}0.153$ unit. As the model depends on the F-B function system of body movement, average values of these perturbation were computed F-B function comparison data. These systems will be to infer a data algorithm and a data signal processing system for the evaluation of the stability.

• Bulletin of the Korean Mathematical Society
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• v.46 no.3
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• pp.535-543
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• 2009

In this paper we study some properties of the Helton class of an operator. In particular, we show that the Helton class preserves the quasinilpotent property and Dunford's boundedness condition (B). As corollaries, we get that the Helton class of some quadratically hyponormal operators or decomposable subnormal operators satisfies Dunford's boundedness condition (B).

• Journal of the Korean Mathematical Society
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• v.59 no.4
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• pp.757-774
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• 2022

Let a and b be positive even integers. An even [a, b]-factor of a graph G is a spanning subgraph H such that for every vertex v ∈ V (G), d_H(v) is even and a ≤ dH(v) ≤ b. Let κ(G) be the minimum size of a vertex set S such that G - S is disconnected or one vertex, and let σ₂(G) = min_uv∉E(G) (d(u)+d(v)). In 2005, Matsuda proved an Ore-type condition for an n-vertex graph satisfying certain properties to guarantee the existence of an even [2, b]-factor. In this paper, we prove that for an even positive integer b with b ≥ 6, if G is an n-vertex graph such that n ≥ b + 5, κ(G) ≥ 4, and σ₂(G) ≥ ${\frac{8n}{b+4}}$, then G contains an even [4, b]-factor; each condition on n, κ(G), and σ₂(G) is sharp.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.9
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• pp.964-975
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• 1990

This paper aims at the design of high voltage electrode contour under specified field condition. Defining the contour with B-Spline curve, the number of contour variables can be reduced and very smooth electrode can be obtained. For the analysis of the electric field, Surface Charge Method which has advantages in practical model has been used. As an initial contour, the rod-plane gap has been used since the difference between maximum and minimum field value is relatively large. Various field conditions including uniform field condition are given to the end of the rod electrode. Under uniform field condition, authors designed an electrode whose field-deviation was under 0.5%. Finally, the relation between the curvature and field of the electrode has been checked, which showed that B-Spline curve is appropriate for the shape function.

• Journal of the East Asian Society of Dietary Life
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• v.4 no.3
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• pp.147-169
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• 1994

This study was conducted to ivestigate the quality of modeled chinese-cabbage Kimchi. The mutual action of sub-ingredients and optimum mixing conditions were examined by analyses of pH, acidity, content of vitamins, carotenes, number of total microorganism, and Lactobacilli, the activities of softening related to enzymes (polygalacturonase and ${\beta}$-galactosidase), and sensory quality during fermentation. The result about the mutual action of red pepler powder and garlic showed that the pH was decresed as concentration of garlic was higher and that of red peppler powder became lower. Kimchi had unpleasant taste and undesirable odor when the adding ratio of the peper powder and garlic was unbalanced. As the concentration of garlic became higher, the content of vitamin C in Kimchi tissue decreased while that of vitamin C in Kimchi juice increased. The contents of vitamin B1, B2 and carotene increased as the concentration of garlic became lower. The optimum mixing ratio of red pepper powder and garlic evaluated by overall eating quality was 4.66% and 3.45%, respectively. The result about the mutual action of ginger and green onion was that pH became higher as the concentration of ginger was 1.84% and that of green onion was 5.96%. The intensity of fresh taste and odor became stronger as the concentration of ginger increaed to 2.76% and that of green onion decreased to 2.98%. The balance of sour, salty and hot taste became better as the concentration of ginger increased and that of green onion decreased. The optimum mixing condition evaluated by overall eating quality was 2.94% in ginger ＋ 2.78% in green onion. The contents of vitamin B1, B2 and C were high in this condition. The result about the mutual action of leek and salted anchovy juice was that pH became lower as the concentration of leek increased and that of salted anchovy juice decreased. Sour, hot and sweet tastes were good in the condition of leek 12%, salted anchovy juice 4.69%. Palatable, fresh taste and odor became weaker when the one of both sub-ingredients was too much little. The optimum mixing condition evaluated by overall easting quality was 9.76% in leek ＋ 7.32% in salted anchovy juice. The contents of vitamin B1, B2, C and carotene were high in this condition and other sensory qualities were good. The result about the mutual action of salt and sugar was that pH became lower as the concentration of sugar became higher and that of salt became lower. The sweet taste was reduced of hot taste than salty taste. Palatable and fresh tastes were desirable when Kimchi fermented with less salt and more sugar. The optimum mixing condition evaluated by overall eating quality was 3.29% in sugar ＋ 4.80% in salt. The contents of vitamin B1, B1, C and carotene were high in this condition. The result of model Kimchi fermented at 20$^{\circ}C$ was that the number of Lactobacilli in model Kimchi was higher than that of in control Kimchi. The fermentation period was extended under pH 4.0 and the contents of vitamin B1, B1,C and carotene were high through the whole edible period. The activity of polygalacturonase was low, but that of ${\beta}$-galactosidase was high during fermentation.