• Journal of the Chungcheong Mathematical Society
• /
• v.31 no.1
• /
• pp.43-46
• /
• 2018

It is concerned with the continuity of the Hardy-Little wood maximal function between the classical Lebesgue spaces or the Orlicz spaces. A new approach to the continuity of the Hardy-Littlewood maximal function is presented through the observation that the continuity is closely related to the existence of solutions for a certain type of first order ordinary differential equations. It is applied to verify the continuity of the Hardy-Littlewood maximal function from $L^p({\mathbb{R}}^n)$ to $L^q({\mathbb{R}}^n)$ for 1 ${\leq}$ q < p < ${\infty}$.

• East Asian mathematical journal
• /
• v.35 no.1
• /
• pp.1-7
• /
• 2019

We consider the initial value problem of the Schrodinger equation for an interesting Cauchy-Euler type operator ${\mathfrak{R}}$ on ${\mathbb{C}}^n$ that is an analogue of the harmonic oscillator in ${\mathbb{R}}^n$. We get an appropriate $L^1-L^{\infty}$ dispersive estimate for the solution of the initial value problem.

• Bulletin of the Korean Mathematical Society
• /
• v.33 no.1
• /
• pp.135-170
• /
• 1996

Recently many people have studied the Sobolev orthogonal polynomials, that is, polynomials which are orthogonal relative to a symmetric bilinear form $\phi(\cdot,\cdot)$ defined by $$ (1.1) $\phi(p,q) := (p,q)_N = \sum_{k=0}^{N} \int_{R}p^(k) (x)q^(k) (x) d\mu_k, $$ where each $d\mu_k$ is a signed Borel measure on the real line $R$ with finite moments of all orders. For the brief history on this subject, we refer to the survey article Ronveaux [13] and Marcellan and et al [10].

• Journal of the Korean Society of Propulsion Engineers
• /
• v.9 no.4
• /
• pp.31-38
• /
• 2005

In this paper, the combustion characteristics of a hybrid propulsion system were studied with various L/D(length vs diameter) ratio of the single po.1 type solid fuel. Experiments were performed for 2 cases with the fixed grain port diameter and fuel length respectively. For the first case, results show that there are no large variations for regression rates as the L/D ratio changes. And as the L/D ratio increases, the O/F ratio decreases and thrust, characteristic velocity tends to increase. For the second case, there is no large change for O/F ratio, thrust and characteristic velocity as L/D ratio changes. On the other hand, as the L/D ratio decreases, only the regression rate tends to increase. Experimentally, exponent n in $\dot{r}=a{G_0}^n$ was found about 0.5 and then the O/F ratio was shown nearly constant. In the experiment, PE and gas oxygen were used as a fuel and an oxidizer.

• Journal of applied mathematics & informatics
• /
• v.10 no.1_2
• /
• pp.245-250
• /
• 2002

Consider the Convex Polygon Pm={Al , A2, ‥‥, Am} With Vertex points A$\_$i/ = (a$\_$i/, b$\_$i/),i : 1,‥‥, m, interior P$\^$0/$\_$m/, and length of perimeter denoted by L(P$\_$m/). Let R$\_$n/ = {B$_1$,B$_2$,‥‥,B$\_$n/), where B$\_$i/=(x$\_$i/,y$\_$I/), i =1,‥‥, n, denote a regular polygon with n sides of equal length and equal interior angle. Kaiser[4] used the regular polygon R$\_$n/ to approximate P$\_$m/, and the problem examined in his work is to position R$\_$n/ with respect to P$\_$m/ to minimize the area of the symmetric difference between the two figures. In this paper we give the quality of a approximating regular polygon R$\_$n/ to approximate P$\_$m/.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 1998.08a
• /
• pp.79.3-79
• /
• 1998

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.30 no.4 s.48
• /
• pp.491-497
• /
• 2004

Holographic quantitative structure activity relationships (HQSAR) between the melanogenesis inhibitory activities of alkyl-3,4-dihydroxybenzoate (A) and N-Alkyl-3,4-dihydroxybenzamide (B) derivatives were analyzed and discussed. The statistical results of HQSAR model for the activities showed the best predictability of the activities based on the cross-validated $r^2_{cv}\;(q^2=0.674),$ non-cross-validated, conventional coefficient $(r^2_{ncv}=0.936).$ The melanogenesis inhibitory activities and hydrolytic reactivity of (A) were slightly higher than that of (B) (A>B) and the activities depends upon the $R_1-substituents\;(R_1>R_2).$ It has been found using frontier molecular orbital (FMO) theory that the hydrolysis reactions of (A) and (B) proceeded to an orbital-controlled reactions, while the nucleophillc addition-elimination reactions $(Ad_{N-E})$ between LUMO energy of (A) and (B) and HOMO energy of water molecule are occurred.

• Journal of the Korean Chemical Society
• /
• v.56 no.4
• /
• pp.440-447
• /
• 2012

Heteroleptic complexes of zirconium (IV) derived from bulky Schiff base ligands containing a sulphur atom and oximes of heterocyclic ${\beta}$-diketones of the general formula ZrLL' (where $LH_2=RCNH(C_6H_4)SC:C(OH)N(C_6H_5)N:CCH_3$, $R=-C_6H_5$, $-C_6H_4Cl(p)$ and $L^{\prime}H_2=R^{\prime}C:(NOH)C:C(OH)N(C_6H_5)N:CCH_3$, $R^{\prime}=-CH_2CH_3$, $-C_6H_5$, $-C_6H_4Cl(p)$ were prepared by the reactions of zirconium tetrachloride with disodium salts of Schiff bases ($L\;Na_2$) and oximes of heterocyclic ${\beta}$-diketones ($L^{\prime}\;Na_2$) in 1:1:1 molar ratio in dry refluxing THF. The structures of these monomeric zirconium (IV) complexes were elucidated with the help of elemental analysis, molecular weight measurements, spectroscopic (IR, NMR and mass) studies. A distorted trigonal bipyramidal geometry may be suggested for these heteroleptic zirconium (IV) complexes. The ligands (bulky Schiff base ligands containing a sulphur atom and oximes of heterocyclic ${\beta}$-diketones) and their heteroleptic complexes of zirconium (IV) were screened against A. flavus, P. aeruginesa and E. coli.

• Journal of Food Hygiene and Safety
• /
• v.28 no.3
• /
• pp.234-240
• /
• 2013

This test was performed to evaluate the bactericidal efficacy of Fumagari OPP$^{(R)}$, fumigation disinfectant, containing 20% ortho-phenylphenol against Escherichia coli (E. coli) and Salmonella typhimurium (S. typhimurium). In preliminary tests, both E. coli and S. typhimurium working culture suspension number (N value) was $4.0{\times}10^8$ CFU/mL. And all of the colony numbers on the carriers exposed the fumigant (n1, n2, n3) were higher than 0.5N1 (the number of bacterial test suspentions by pour plate method), 0.5N2 (the number of bacterial test suspentions by filter membrane method) and 0.5N1, respectively. In addition, the mean number of bacteria recovered on the control-carriers (T value) was $3.4{\times}10^6$ CFU/mL. In the bactericidal effect of the fumigant, the reduction number of S. typhimurium and E. coli (d value) was 5.26 and 5.64 logCFU/mL, respectively. According to the French standard for the fumigant, the d value for the effective bactericidal fumigant should be over than 5 logCFU/mL. With the results of this study, Fumagari OPP$^{(R)}$ has an effective bactericidal activity, then the fumigant can be applied to disinfect food materials and kitchen appliances contaminated with pathogenic bacteria.

• Journal of Korean Physical Therapy Science
• /
• v.9 no.2
• /
• pp.67-75
• /
• 2002

The purpose of this study is to know the average of hip joint range of motion and difference according to the aging for the elderly. This study consisted of elder male(n=75) and elder female(n=109). The result of assessment and analysis in hip pint range of motion are as follows : 1) The average hip flexion(knee flexed) joint range of motion in 60-69(from sixty to sixty-nine)years old are $104.26^{\circ}$(Left-Male), $101.00^{\circ}$(Right-Male), $107.05^{\circ}$(Left-Female), $107.05^{\circ}$(Right-Female). 70-79years old are $104.59^{\circ}$(L-M), $102.05^{\circ}$(R-M), $105.73^{\circ}$(L-F), $108.75^{\circ}$(R-F). 80-89years old are $101.53^{\circ}$(L-M), $101.13^{\circ}$(R-M), $96.83^{\circ}$(L-F), $97.67^{\circ}$(R-F). There was significant difference in hip flexion(knee flexed) among female group(p<.01). The average hip flexion(knee extended) joint range of motion in 60-69(from sixty to sixty-nine)years old are $73.13^{\circ}$(Left-Male), $72.04^{\circ}$(Right-Male), $77.29^{\circ}$(Left-Female), $75.97^{\circ}$(Right-Female). 70-79years old are $74.95^{\circ}$(L-M), $72.19^{\circ}$(R-M), $76.73^{\circ}$(L-F), $76.65^{\circ}$(R-F). 80-89years old are $70.83^{\circ}$(L-M), $70.37^{\circ}$(R-M), $69.00^{\circ}$(L-F), $69.00^{\circ}$(R-F). There was significant difference in left hip flexion(knee extended) among female group(p<.05). 2) The average hip extension joint range of motion in 60-69years old are $13.09^{\circ}$(L-M), $12.78^{\circ}$(R-M), $10.97^{\circ}$(L-F), $10.68^{\circ}$(R-F). 70-79years old are $8.95^{\circ}$(L-M), $8.48^{\circ}$(R-M), $11.24^{\circ}$(L-F), $10.90^{\circ}$(R-F). 80-89 years old are $8.40^{\circ}$(L-M), $8.23^{\circ}$(R-M), $7.33^{\circ}$(L-F), $7.33^{\circ}$(R-F). There was significant difference in left(p<.01) and right(p<.05) hip extension among male group(p<.05). 3) The average hip abduction joint range of motion in 60-69 years old are $33.04^{\circ}$(L-M), $33.17^{\circ}$(R-M), $33.16^{\circ}$(L-F), $33.37^{\circ}$(R-F). 70-79 years old are $31.00^{\circ}$(L-M), $30.05^{\circ}$(R-M), $32.44^{\circ}$(L-F), $32.68^{\circ}$(R-F). 80-89 years old are $29.07^{\circ}$(L-M), $27.90^{\circ}$(R-M), $28.17^{\circ}$(L-F), $28.67^{\circ}$(R-F). There was no significant difference among group. 4) The average hip adduction pint range, of motion in 60-69years old are $29.57^{\circ}$(L-M), $29.35^{\circ}$(R-M), $31.87^{\circ}$(L-F), $31.89^{\circ}$(R-F). 70-79, years old are $27.41^{\circ}$(L-M), 27.00(R-M) $30.85^{\circ}$(L-F), $31.28^{\circ}$(R-F). 80-89 years old are $26.87^{\circ}$(L-M), $26.63^{\circ}$(R-M), $24.67^{\circ}$(L-F), $24.83^{\circ}$(R-F). There was significant difference in hip abduction among female group(p<01). 5) The average hip external rotation pint range of motion in 60-69years old are $32.26^{\circ}$(L-M), $31.17^{\circ}$(R-M), $33.53^{\circ}$(L-F), $34.42^{\circ}$(R-F). 70-79 years old are $31.64^{\circ}$(L-M), $28.62^{\circ}$(R-M) $31.29^{\circ}$(L-F), $31.45^{\circ}$(R-F). 80-89 years old are $26.40^{\circ}$(L-M), $26.07^{\circ}$(R-M), $24.77^{\circ}$(L-F), $24.27^{\circ}$(R-F). There was significant difference in left(male, female p<.01) and right(female p<.0l) hip external rotation among group. 6) The average hip internal rotation joint range of motion in 60-69years old are $30.30^{\circ}$(L-M), $28.13^{\circ}$(R-M), $34.27^{\circ}$(L-F), $36.03^{\circ}$(R-F). 70-79years old are $31.24^{\circ}$(L-M), $29.57^{\circ}$(R-M), $28.51^{\circ}$(L-F), $29.10^{\circ}$(R-F). 80-89 years old are $24.63^{\circ}$(L-M), $24.40^{\circ}$(R-M), $24.27^{\circ}$(L-F), $24.27^{\circ}$(R-F). There was significant difference in left(male p<.05, female p<.01) and right(female p<.01) hip internal rotation among group.