• Journal of the Korean Ceramic Society
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• v.39 no.1
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• pp.99-107
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• 2002

Impedance Spectroscopy (IS) has been used to study microstructure and hydration mechanism of cement pastes. In this work, the early hydration behaviour of portland cement paste with different blame values and contents of blast-furnace slag was investigated by IS. As slag was added to portland cement, the values of $R_{t(s+1)}$ (the solid-liquid phase resistance) and $R_{t(int)}$ were decreased in the early hydration period. It showed that hydration of cement paste containing slag was slower than it of the reference cement paste. As the content of slag was increased, the values of $R_{t(s+1)}$ was decreased. Furthermore, the diameter of semicircle, $R_{t(int)}$ observed at 72 hours was decreased with the increment of slag content. However, the values of $R_{t(s+1)}$ and $R_{t(int)}$ were increased with blame value of slag from the early hydration period.

• Journal of the Korean Mathematical Society
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• v.34 no.4
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• pp.1029-1036
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• 1997

Let ${A_t)}_{t>0}$ be a dilation group given by $A_t = exp(-P log t)$, where P is a real $n \times n$ matrix whose eigenvalues has strictly positive real part. Let $\nu$ be the trace of P and $P^*$ denote the adjoint of pp. Suppose that $K$ is a function defined on $R^n$ such that $$\mid$K(x)$\mid$ \leq k($\mid$x$\mid$_Q)$ for a bounded and decreasing function $k(t) on R_+$ satisfying $k \diamond $\mid$\cdot$\mid$_Q \in \cup_{\varepsilon >0}L^1((1 + $\mid$x$\mid$)^\varepsilon dx)$ where $Q = \int_{0}^{\infty} exp(-tP^*) exp(-tP)$ dt and the norm $$\mid$\cdot$\mid$_Q$ stands for $$\mid$x$\mid$_Q = \sqrt{}, x \in R^n$. For $f \in L^1(R^n)$, define $mf(x) = sup_{t>0}$\mid$K_t * f(x)$\mid$$ where $K_t(X) = t^{-\nu}K(A_{1/t}^* x)$. Then we show that $m$ is a bounded operator of $L^1(R^n) into L^{1, \infty}(R^n)$.

• Journal of the Korean Mathematical Society
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• v.37 no.4
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• pp.521-530
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• 2000

We find the values of numerical invariants col(R) and row (R) for R=k[te, te+1, t(e-1)e-1] where k is a field and e$\geq$4. We also show that col(R) = crs (R) and row (R) = drs(R), but they are strictly less than the reduction number of R plus 1.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.9 no.1
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• pp.79-90
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• 2005

In this paper we study the numerical solutions of the stochastic differential equations of the form $$du(x,\;t)=f(x,\;t,\;u)dt\;+\;g(x,\;t,\;u)dW(t)\;+\;\sum\limits_{|q|\leq2m}\;A_q(x,\;t)D^qu(x,\;t)dt$$ where $0\;{\leq}\;t\;{\leq}\;T,\;x\;{\in}\;R^{\nu}$, ($R^{nu}$ is the $\nu$-dimensional Euclidean space). Here $u\;{\in}\;R^n$, W(t) is an n-dimensional Brownian motion, $$f\;:\;R^{n+\nu+1}\;{\rightarrow}\;R^n,\;g\;:\;R^{n+\nu+1}\;{\rightarrow}\;R^{n{\times}n},$$, and $$A_q\;:\;R^{\nu}\;{\times}\;[0,\;T]\;{\rightarrow}\;R^{n{\times}n}$$ where ($A_q,\;|\;q\;|{\leq}\;2m$) is a family of square matrices whose elements are sufficiently smooth functions on $R^{\nu}\;{\times}\;[0,\;T]\;and\;D^q\;=\;D^{q_1}_1_{\ldots}_{\ldots}D^{q_{\nu}}_{\nu},\;D_i\;=\;{\frac{\partial}{\partial_{x_i}}}$.

• Journal of Practical Agriculture & Fisheries Research
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• v.13 no.1
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• pp.131-136
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• 2011

For the establishment of seed production technique of warm water abalone species Haliotis sieboldii, development of the fertilized eggs and its biological minimum temperature were determined. The durations of each development stages at the six rearing temperature regimes were expressed as an exponential equation: 4 celled stage 1/h = 0.1346T - 2.1709(r² = 0.88) Morula stage 1/h = 0.0176T - 0.2184 (r² = 0.89) Trochophore 1/h = 0.0063T - 0.0512 (r² = 0.98) Veliger 1/h = 0.0045T - 0.0295 (r² = 0.99) 2nd c.t. 1/h = 0.0008T - 0.0047 (r² = 0.99) According to the equation, the biological minimum temperature for Haliotis sieboldii was estimated to be 9.7 ℃.

• Journal of the Korean Mathematical Society
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• v.51 no.2
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• pp.239-250
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• 2014

Let R be a commutative Noetherian (not necessarily local) ring, I an ideal of R and M a finitely generated R-module. In this paper, by computing the local cohomology modules and Ext-modules via the injective resolution of M, we proved that, if for an integer t > 0, dim$_RH_I^i(M){\leq}k$ for ${\forall}i$ < t, then $$\displaystyle\bigcup_{i=0}^{j}(Ass_RH_I^i(M))_{{\geq}k}=\displaystyle\bigcup_{i=0}^{j}(Ass_RExt_R^i(R/I^n,M))_{{\geq}k}$$ for ${\forall}j{\leq}t$ and ${\forall}n$ >0. This shows that${\bigcup}_{n>0}(Ass_RExt_R^i(R/I^n,M))_{{\geq}k}$ is a finite set for ${\forall}i{\leq}t$. Also, we prove that $\displaystyle\bigcup_{i=1}^{r}(Ass_RM/(x_1^{n_1},x_2^{n_2},{\ldots},x_i^{n_i})M)_{{\geq}k}=\displaystyle\bigcup_{i=1}^{r}(Ass_RM/(x_1,x_2,{\ldots},x_i)M)_{{\geq}k}$ if $x_1,x_2,{\ldots},x_r$ is M-sequences in dimension > k and $n_1,n_2,{\ldots},n_r$ are some positive integers. Here, for a subset T of Spec(R), set $T_{{\geq}i}=\{{p{\in}T{\mid}dimR/p{\geq}i}\}$.

• Journal of Aquaculture
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• v.4 no.1
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• pp.13-18
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• 1991

In order to obtain basic biological data for effective seed production of the red sea bream, Pargus major, the influence of water temperature on egg development was investigated. The time of egg development was shorter with higher water temperature. The relationships between the water temperature($T\;:\;^{\circ}C$) and the required time(t : hour) from egg to each developmental stage were given as follows : 8-cell 1/t=0.0618T-0.5877(r=0.9899) Morula : 1/t=0.0284T-0.2556(r=0.9948) Kupffer's : 1/t=0.0076T-0.0829(r=0.9902) vesicle Hatching : 1/t=0.0031T-0.0350(r=0.9985) Biological minimium temperature for the egg development was estimated to be $10.2^{\circ}C$ in average.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.777-786
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• 2003

An experiment was conducted to investigate the effects of supplementary Blended essential oil(CRINA$^{\circledR}$) on the performance, nutrient availability, fatty acid composition of leg muscle, small intestinal microflora and blood parameters in broiler chickens. One thousand unsexed day-old broiler chickens were assigned to five treatments : control(T1), 5ppm avilamycin(starter diet) & 5ppm flavomycin(grower diet) T2, 5ppm avilamycin(starter diet) & 50ppm CRINA$^{\circledR}$(grower diet) T3, 50ppm CRINA$^{\circledR}$(starter & grower diet) T4, 50ppm CRINA$^{\circledR}$+ 500ppm lactic acid$^{\circledR}$ (starter & grower diet) T5. Each treatment had four replications of 50 birds each. Growth performance was significantly improved by dietary supplements(T2-T5). There were no significant differences among treatment T2, T3, T4 and T5. Feed intake was not significantly different among treatments. Dietary supplementation of CRINA$^{\circledR}$(T3, T4, T5) resulted in significant(p〈0.05) improvement in feed/gain(F/G) during finishing period (4-5weeks). The birds fed CRINA$^{\circledR}$ supplemented diet(T4) showed significantly(p〈0.05) higher availability of crude fat, methionine and methionine + cystine than those fed antibiotics supplemented diet(T2). Mortality was not significantly affected by treatments. The colony forming unit(CFU) of E.coli in small intestinal content was significantly lower in antibiotics & CRINA$^{\circledR}$(T3) compared to CRINA$^{\circledR}$ treatment(T4)(P〈0.05). CFU of Cl. perfringens was low in CRINA$^{\circledR}$(T4) but not different significantly with other treatments. Serum triglyceride level of birds fed CRINA$^{\circledR}$ + lactic acid diet(T5) was significantly lower(p〈0.05) than those fed antibiotics supplemented diet(T2). Cholesterol level of the birds fed antibiotics(T2) or CRINA$^{\circledR}$ + lactic acid supplemented diet(T5) was significantly higher(p〈0.05) than other treatments. HDL level of birds fed control diet was significantly lower(p〈0.05) than that of others. The levels of serum IgG were not significantly different among treatments. Major fatty acids composition of leg muscle fat was significantly influenced by treatments. Control group showed significantly higher palmitic acid(C$_{16:0}$) and steraric acid(C$_{18:0}$) content than other treatments(p〈0.05). Content of oleic acid(C$_{18:1}$), however, was significantly lower in the control than others treatments. Content of linolenic acid(C$_{18:3}$) was significantly higher in CRINA$^{\circledR}$+ lactic acid(T5) than antibiotics & CRINA$^{\circledR}$(T3) treatments. Total saturated fatty acids content was higher and total unsaturated fatty acids were lower in the leg muscle fat of the control than that of other treatments. It is concluded that CRINA$^{\circledR}$ supplementation improved growth rate and F/G ratio in broilers. The combination of CRINA$^{\circledR}$ with either antibiotics or lactic acid did not show any additive or synergistic effects in broiler chickens .

• Journal of the Korean Mathematical Society
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• v.52 no.6
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• pp.1253-1270
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• 2015

Let (R, m) be a commutative Noetherian local domain, M a non-zero finitely generated R-module of dimension n > 0 and I be an ideal of R. In this paper it is shown that if $x_1,{\ldots },x_t$ ($1{\leq}t{\leq}n$) be a sub-set of a system of parameters for M, then the R-module $H^t_{(x_1,{\ldots },x_t)}$(R) is faithful, i.e., Ann $H^t_{(x_1,{\ldots },x_t)}$(R) = 0. Also, it is shown that, if $H^i_I$ (R) = 0 for all i > dim R - dim R/I, then the R-module $H^{dimR-dimR/I}_I(R)$ is faithful. These results provide some partially affirmative answers to the Lynch's conjecture in [10]. Moreover, for an ideal I of an arbitrary Noetherian ring R, we calculate the annihilator of the top local cohomology module $H^1_I(M)$, when $H^i_I(M)=0$ for all integers i > 1. Also, for such ideals we show that the finitely generated R-algebra $D_I(R)$ is a flat R-algebra.

• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.332-338
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• 1999

This study was carried out to investigate weight gain and prevention of diarrhea in suckling calves which were injected with recombinant bovine somatopropin (rBST). A total of 101 breeding cows were assigned to the six groups according to the administered dosage and injected time, respectively. Groups T-1, T-3, T-4 and T-6 were injected starting 1 week before calving and groups T-2 and T-5 were injected on the calving day. The six groups were injected five times at two week intervals. Groups T-1 and T-2 were injected with 250mg composite rBST, Group T-3 was injected with 375 mg composite rBST. Groups T-4 and T-5 were injected with 500mg composite rBST, And group T-6 was injected with 500mg rBST-S. The control group was not injected with BST. The groups injected with 500 mg BrST had a lower rate of morbidity from diarrhea than the control group or the groups injected with 250 mg rBST (T-1 and T-2). Weight gain was higher in group T-4 than in the control group or groups T-1 and T-2. In Korean Native Cattle, the total weight gain was greater in group T-4 than in the control group (p<0.05). In crossbred cows, total weight gain was the highest in group T-4, and the total weight gain rate was greater than in group T-4 and the control group (p<0.05). The results of the hematological values showed that injections of rBST did not affect the level of the RBC, TP and BUN in the breeding cows at 9 weeks after postpartum or the neonatal calves. The results of this study indicate that injecting breeding cows with 500 mg rBST before calving would be effective in the preventing of diarrhea and in increasing weight gain of calves from birth to weaning.