• Bulletin of the Korean Mathematical Society
• /
• 제55권2호
• /
• pp.573-586
• /
• 2018

Let R be a noncommutative prime ring of characteristic different from 2, Q be its maximal right ring of quotients and C be its extended centroid. Suppose that $f(x_1,{\ldots},x_n)$ be a noncentral multilinear polynomial over $C,b{\in}Q,F$ a b-generalized derivation of R and d is a nonzero derivation of R such that d([F(f(r)), f(r)]) = 0 for all $r=(r_1,{\ldots},r_n){\in}R^n$. Then one of the following holds: (1) there exists ${\lambda}{\in}C$ such that $F(x)={\lambda}x$ for all $x{\in}R$; (2) there exist ${\lambda}{\in}C$ and $p{\in}Q$ such that $F(x)={\lambda}x+px+xp$ for all $x{\in}R$ with $f(x_1,{\ldots},x_n)^2$ is central valued in R.

• Communications of the Korean Mathematical Society
• /
• 제27권1호
• /
• pp.57-68
• /
• 2012

The commuting graph of an arbitrary ring R, denoted by ${\Gamma}(R)$, is a graph whose vertices are all non-central elements of R, and two distinct vertices a and b are adjacent if and only if ab = ba. In this paper, we investigate the connectivity, the diameter, the maximum degree and the minimum degree of the commuting graph of group ring $Z_nQ_8$. The main result is that $\Gamma(Z_nQ_8)$ is connected if and only if n is not a prime. If $\Gamma(Z_nQ_8)$ is connected, then diam($Z_nQ_8$)= 3, while $\Gamma(Z_nQ_8)$ is disconnected then every connected component of $\Gamma(Z_nQ_8)$ must be a complete graph with a same size. Further, we obtain the degree of every vertex in $\Gamma(Z_nQ_8)$, the maximum degree and the minimum degree of $\Gamma(Z_nQ_8)$.

• Korean Journal of Agricultural and Forest Meteorology
• /
• 제21권3호
• /
• pp.196-207
• /
• 2019

This study was carried out to investigate the effects of C. japonica, D. morbifera, D. macropodum, I. anisatum, Q. glauca and R. indica To investigate the photosynthetic ability, chlorophyll content, chlorophyll fluorescence analysis, and physiological environmental. The photosynthetic rate, cancer respiration rate, stomatal conductance, and rate of evaporation tended to decrease as a result of drying stress in the no-water condition for 28 days. I. anisatum, Q. glauca and R. indica showed a low rate of less than 40% until 28 days of no-treatment. The total chlorophyll contents were decreased in the order of D. macropodum> D. morbifera> C. japonica> Q. glauca> M. thunbergii> R. indica> I. anisatum. Chlorophyll fluorescence analysis showed that there was no change in the qP, but after 28 days no $Fv/F_m$, $F_o$, $R_{fd}$, $NPQ_{_-LSS}$ can be a useful indicator for quantitative estimation within a short period of time with a marked reduction rate of PSII quantum yield ${\Phi}PSII$ in the rectified state by continuous light during the nominal adaptation period. In the case of I. anisatum, Q. glauca and R. indica If water management can be carried out at intervals, it may be possible to plant trees in trees and landscape trees.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권2호
• /
• pp.803-809
• /
• 2015

Background: Colorectal cancer (CRC) is a leading cause of cancer-related death. Oxidative DNA damage may contribute to cancer risk and the antioxidant paraoxonase is one endogenous free radical scavenger in the human body which could therefore exert an influeence. Purpose: Aim of this study was to determine the role of serum arylesterase (ARE) and paraoxonase 1(PON1) activities in CRC patients and to find any association between (PON1) Q192R and L55M gene polymorphisms in CRC patients. Also the serum ARE and PON1 activities in CRC patients will be investigated before and after surgery Materials and Methods: This study involved a total of 50 patients with newly diagnosed CRC and 80 healthy controls. PON1 and ARE activities were determined using an enzymatic spectrophotometric method. PON1 Q192R and L55M gene polymorphisms were determined using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) based restriction fragment analysis. The restriction enzyme AlwI was used to examine the Q192R polymorphism and Hsp92II for the L55M polymorphism. Results: Significant differences in the PON1 Q192R polymorphism were found between patients and controls. The Q allele was more frequent in the patient group than in controls, while the R allele was more frequent in the controls. Significant differences were found in the L55M polymorphism. Additionally, there were significant differences in L and M allele frequencies (p=0.001). The serum activities of PON1 and ARE were low in QQ and MM genotype. Conclusions: serum PON1 and ARE activities were significantly lower in CRC patients compared to healthy subjects. The R allele may protect against colorectal cancer.

• Journal of the Chungcheong Mathematical Society
• /
• 제22권1호
• /
• pp.117-121
• /
• 2009

For $1{\leq}p$, $q{\leq}{\infty}$ and $s{\in}\mathbb{R}$, it is proved that there exists a constant C > 0 such that for any $f{\in}B^{s+2}_{p,q}(\mathbb{R}^n)$ $${\parallel}f{\parallel}_{B^{s+2}_{p,q}(\mathbb{R}^n)}{\leq}C{\parallel}f\;-\;{\Delta}f{\parallel}_{B^{s}_{p,q}(\mathbb{R}^n)}$$, which tells us that the operator $I-\Delta$ is $B^{s+2}_{p,q}$-coercive on the Besov space $B^s_{p,q}$.

• The Korean Journal of Pesticide Science
• /
• 제7권2호
• /
• pp.75-82
• /
• 2003

We discuss that the growth inhibition activities against root and shoot of rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) by N-phenyl-3,4,5,6-tetrahydrophthalimide (A) and N-phenyl-3,4-dimethylmaleimide (B) derivatives with changing substituents can be explained and predicted using comparative molecular field analyses (CoMPA) method. And the results show that the cross-validation value, $q^2$ at three components and Pearson correlation coefficient, $r^2$ were rice plant: shoot; $r^2=0.987$, $q^2=0.387$ & root; $r^2=0.923$, $q^2=0.307$ and barnyard grass: shoot; $r^2=0.902$, $q^2=0.535$ & root; $r^2=0.900$, $q^2=0.450$, respectively. In addition, The activities of unknown compounds were predicted by CoMFA method. From the contour map of (A) derivatives, the selective factors to remove barnyard grass takes positive charge on the benzylic carbon atom (C27), negative charged carbon atom (C29) of meta position and steric bulky groups on the cyclic imino ring (C7-C8).

• Journal of Ginseng Research
• /
• 제33권3호
• /
• pp.240-243
• /
• 2009

To better understand how to increase a ginseng grower's revenue, a 4-factor revenue determination model (RDM) of raw ginseng production (R=A Y Q P) was proposed. The total revenue (R) is a multiplicative function of four factors: cultivation area(A), unit yield (Y), quality grade (Q) and unit price (P). The A appears to be a pure capital factor. Y and Q are technological factors and P is social and market factor. When P is constant, the technological term (YQ) is the revenue per unit area (R/A) production efficiency per capital. The RDM appears to be a linear model between R and A with the slope [YQ]. RDM was applied to three farmers' raw ginseng production for assessment of its dependency on capital and technological factors.

• Honam Mathematical Journal
• /
• 제17권1호
• /
• pp.107-118
• /
• 1995

We study the asymptotic behavior of nonnegative singular solutions of semilinear parabolic equations of the type $$u_t={\Delta}u-(u^q)_y-u^p$$ defined in the whole space $x=(x,y){\in}R^{N-1}{\times}R$ for t>0, with initial data a Dirac mass, ${\delta}(x)$. The exponents q, p satisfy $$1 where $q^*=max\{q,(N+1)/N\}$.

• Bulletin of the Korean Mathematical Society
• /
• 제52권4호
• /
• pp.1047-1057
• /
• 2015

In [6], it is proved that the lengths of periods occurring in the ${\beta}$-expansion of a rational series r noted by $Per_{\beta}(r)$ depend only on the denominator of the reduced form of r for quadratic Pisot unit series. In this paper, we will show first that every rational r in the unit disk has strictly periodic ${\beta}$-expansion for Pisot or Salem unit basis under some condition. Second, for this basis, if $r=\frac{P}{Q}$ is written in reduced form with |P| < |Q|, we will generalize the curious property "$Per_{\beta}(\frac{P}{Q})=Per_{\beta}(\frac{1}{Q})$".

• Journal of the Korean Mathematical Society
• /
• 제48권2호
• /
• pp.431-447
• /
• 2011

We investigate the asymptotic behavior of positive solutions to the elliptic equation (0.1) ${\Delta}u+|x|^{l_1}u^p+|x|^{l_2}u^q=0$ in $\mathbb{R}^n$. We obtain a conclusion that, for n $\geq$ 3, -2 < $l_2$ < $l_1$ $\leq$ 0 and q > p > 1, any positive radial solution to (0.1) has the following properties: $lim_{r{\rightarrow}{\infty}}r^{\frac{2+l_1}{p-1}}\;u$ and $lim_{r{\rightarrow}0}r^{\frac{2+l_2}{q-1}}\;u$ always exist if $\frac{n+1_1}{n-2}$ < p < q, $p\;{\neq}\;\frac{n+2+2l_1}{n-2}$, $q\;{\neq}\;\frac{n+2+2l_2}{n-2}$. In addition, we prove that the singular positive solution of (0.1) is unique under some conditions.