• Korean Journal of Mathematics
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• v.18 no.4
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• pp.335-342
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• 2010

Let D be an integral domain with quotient field K,$\mathcal{I}(D)$ be the set of nonzero ideals of D, and $w$ be the star-operation on D defined by $I_w=\{x{\in}K{\mid}xJ{\subseteq}I$ for some $J{\in}\mathcal{I}(D)$ such that J is finitely generated and $J^{-1}=D\}$. The D is called a Pr$\ddot{u}$fer $v$-multiplication domain if $(II^{-1})_w=D$ for all nonzero finitely generated ideals I of D. In this paper, we show that D is a Pr$\ddot{u}$fer $v$-multiplication domain if and only if $(A{\cap}(B+C))_w=((A{\cap}B)+(A{\cap}C))_w$ for all $A,B,C{\in}\mathcal{I}(D)$, if and only if $(A(B{\cap}C))_w=(AB{\cap}AC)_w$ for all $A,B,C{\in}\mathcal{I}(D)$, if and only if $((A+B)(A{\cap}B))_w=(AB)_w$ for all $A,B{\in}\mathcal{I}(D)$, if and only if $((A+B):C)_w=((A:C)+(B:C))_w$ for all $A,B,C{\in}\mathcal{I}(D)$ with C finitely generated, if and only if $((a:b)+(b:a))_w=D$ for all nonzero $a,b{\in}D$, if and only if $(A:(B{\cap}C))_w=((A:B)+(A:C))_w$ for all $A,B,C{\in}\mathcal{I}(D)$ with B, C finitely generated.

• Journal of Elementary Mathematics Education in Korea
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• v.23 no.3
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• pp.273-288
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• 2019

This study focuses on understanding proportionality, in particular, what constitutes relational understanding of a:b=c:d, which is called proportional expression. The meanings of a:b=c:d are analyzed and some suggestions are offered for improving the teaching and learning of it. The equation a:b=c:d has three different meanings. First, it represents two different structures in one proportional situation. Second, it represents a common structure in two different proportional situations. Finally, it represents a number or a quantity underlying in different proportional situations. It is important to choose and use a unit flexibly to understand the first and the second meanings of a:b=c:d, Double strip diagram and double number line are useful to visualize the meanings of a:b=c:d. In addition, what a number or a quantity in the third meaning of a:b=c:d refers to in proportional situations should be emphasized in teaching and learning of a:b=c:d.

• Bulletin of the Korean Mathematical Society
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• v.47 no.5
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• pp.907-913
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• 2010

Let D be an integrally closed domain with quotient field K, * be a star operation on D, X, Y be indeterminates over D, $N_*\;=\;\{f\;{\in}\;D[X]|\;(c_D(f))^*\;=\;D\}$ and $R\;=\;D[X]_{N_*}$. Let b be the b-operation on R, and let $*_c$ be the star operation on D defined by $I^{*_c}\;=\;(ID[X]_{N_*})^b\;{\cap}\;K$. Finally, let Kr(R, b) (resp., Kr(D, $*_c$)) be the Kronecker function ring of R (resp., D) with respect to Y (resp., X, Y). In this paper, we show that Kr(R, b) $\subseteq$ Kr(D, $*_c$) and Kr(R, b) is a kfr with respect to K(Y) and X in the notion of [2]. We also prove that Kr(R, b) = Kr(D, $*_c$) if and only if D is a $P{\ast}MD$. As a corollary, we have that if D is not a $P{\ast}MD$, then Kr(R, b) is an example of a kfr with respect to K(Y) and X but not a Kronecker function ring with respect to K(Y) and X.

• Journal of Korea Foresty Energy
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• v.17 no.1
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• pp.23-29
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• 1998

This study was carried out to develop the regression model for estimating biomass of natural Pinus densiflora forests by stand density in northeast Chinese area of Mt. Paekdu. Four allometric regression models(W=aD$^b$, W=a(D$^2$H)$^b$. logW=a+b$\cdot$ logD+cD and logW=a+b$\cdot$log(D$^2$H)+c(D$^2$H)) were used to estimate biomass for each of the tree components. The suitable regression model for estimating biomass of stem, bark and whole tree above ground was logW=a+b$\cdot$log(D$^2$H)+c(D$^2$H), and that for biomass of branch, needle and needle area, logW=a+b$\cdot$logD+cD for all of the stand density classes.

• Journal of the Korean housing association
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• v.10 no.1
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• pp.11-19
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• 1999

This study is for the development of C.B.D. residential land that is available in the changeable housing market and urban planning paradigm. The results are as follows. First, we developed a Logit model to analyzed the suitable resident for living downtown and we used several variables in the model such as their living place, the location of their works, in come according to sex and age, and whether they have a car or not. Second, in analysis for the suitable residents using the Logit model, the main demanders who live in C.B.D. or have a job there and the young and old were chosen, Third, it shows that the suitable residents prefer semi-C.B.D. because it has convenient accessibility to C.B.D. rater quickly (in ten minutes). They prefer apartment and Mixed-Use building. Fourth, there are much residential land in semi-C.B.D. (63.7%) so as to support enough land in ease of redevelopment. The land price is tremendously low compared to that of land for business or for C.B.D.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.972-978
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• 2005

The present study was carried out to investigate the blood markers of Jeju horses. The redcell cypes (blood groups) and blood protein types (biochemical polymorphisms) were tested from 102 Jeju horses by serological and electrophoretc procedure, and their phenotypes and gene frequencies were estimated. The blood group and biochemical polymorphism phenotypes observed with high frequency were $A^{af}\;(27.45\%$), $C^{a}\;(99.02\%$), $K^{-}\;(97.06\%$), $U^{a}\;(62.75\%$), $P^{b}\;(36.27\%$), $Q^{c}\;(47.06\%$), $D^{cgm/dghm}\;(13.73\%$), $D^{adn/cgm}\;(9.80\%$), $D^{ad/cgm}$\;(8.82\%$), $D^{dghm/dghm}(7.84\%$), $D^{cgm/cgm}(7.84\%$), $AL^{B}\;(48.04\%$), $GC^{F}\;(99.02\%$), $AlB^{K}\;(97.06\%$), $ES^{FI}\;(36.27\%$), $TF^{F2}\;(25.49\%$), $HB^{B1}\;(45.10\%$), and $PGD^{F}\;(86.27\%$) in Jeju horses, respectively. Alleles observed with high gene frequency were $A^{af}$ (0.3726), $A^{C}$ (0.2647), $C^{-}$ (0.5050), $K^{-}$ (0.9853), $U^{-}$ (0.6863), $P^{b}$ (0.4657), $Q^{c}$ (0.5294), $D^{cgm}$ (0.3039), $HB^{B1}$(0.6863), $PGD^{F}$ (0.9265), $AL^{B}$ (0.6912), $ALB^{K}$ (0.9852), $GC^{F}$ (0.9950), $ES^{I}$ (0.5000) and $TF^{F2}$ (0.4950) in Jeju horses, and sfecific alleles, $D^{cgm(f)}$ (0.0196), $HB^{A}$ (0.0147), $HB^{A2}$ (0.0196), $ES^{G}$ (0.0441), $ES^{H}$ (0.0098), $TF^{E}$TF'(0.0246), $TF^{H2}$ (0.0049) and $PGD^{D}$ (0.0098) were detected in Jeju horses. These preliminary results present basic information for detecting the genetic markers in Jeju horse. and developing a system for parentage verification and individuals identification in jeju horses.

• Korean Journal of Animal Reproduction
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• v.21 no.2
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• pp.197-205
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• 1997

Improved hypophysectomy technique and the efficacy of bGH in hypophysectomized female rats were studied as a basis for the function of endocrine gland and hormones. 1. With improved sublaryngeal a, pp.oach by hypophysectomy, 34 rats out of 40 were successfully hypophysectomized(more than 80% of success). The surgical time for hypophysectomy per rat was taken about 3.0$\pm$1.0 min. 2. For the effect of hypophysectomy and bGH on body weight gain among the 5 gruops of A, B, C, D, and E, the weight gains for A, B, C, D, and E, were 93g, 9.2g, 10.7g, 25.1g and 36.2g, respectively, which implied that hypophysectomy had a major effect on body weight. And also, the effect of bGH was paralleled with the level of bGH. There were significant difference between control and hypophysectomized groups, and between the bGH treated and bGH non-treated groups after hypophysectomy(p<0.01). 3. For the effect of hypophysectomy and bGH on the length of femur, tibia, humerus, and anterbrachi, longest was for A, shortest for B, and longer in order of C, D, and E. The A group was significantly longer than B, C, D, and E groups. The B group was shorter than C, D, and E groups(p<0.01). 4. For the effect of hypophysectomy and bGH on the weight of femur, tibia, humerus, and antebrachi, heaviest was for A, lightest for B, and heavier in order of C, D, and E. The A group was significantly heavier than B, C, D, and E groups. The B group was lighter than C, D, and E groups(p<0.01). 5. In changes of body length, and weights of liver and heart, A group was most drastically increased. Among the hypophysectomized groups, the change was increased in order of B, C, D, and E. Especially, the change of A group was significantly greater than B, C, D and E gruops. However, no significant differences were found among B, C, D, and E groups. 6. The hypophysectomy in rat had a significant effect on body growth. The effect of hormone was remarkably different depending upon the level of hormone. It was found that 300$\mu\textrm{g}$ of bGH/kg of body wt/day was slightly lower for normal growth.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.192-196
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• 1985

Eight strains of Lactobacilli(a, b, b', c, d, e, f and g) were isolated from seven Korean liquid-yogurts(A, B, C, D, E, F and G), and identification and tolerance-test to digestive fluids were carried out. Isolate a from yogurt A and isolate a from yogurt E were identified as L. casei, isolate b from yogurt B as L. acidophilus, isolate d from yogurt D as L. bulgaricus, isolate f from yogurt F as L. helveticus, and isolate b' from yogurt B, isolate c from yogurt C and isolate g from yogurt G as L. jugurti, respectively. Isolate f(L. helveticus) and c(L. jugurti) showed high tolerance to artificial gastric juice but didn't to bile acid. Isolate b(L. acidophilus), a(L. casei), and e(L. casei) showed high tolerance to both artificial gastric juice and bile acid, but isolate d(L. bulgaricus), b'(L. jurgurti) and g(L. jugurti) did not.

• Food Science and Preservation
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• v.14 no.6
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• pp.571-577
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• 2007

Storage characteristics of fresh and thawed sliced raw fish (flounder and rockfish) washed in different solutions (tap water, A; jade water, B; 0.2% chitosan-ascorbate (CA), C; 0.03 ppm ozone water, D; 1.5% vinegar containing jade water, E; 1.5% vinegar and 0.2% CA containing jade water, F) at $10^{\circ}C$ were investigated. Changes in pH and acidity of thawed sliced raw fish (TS) during storage were lower than for fresh sliced raw fish (DS). The total microbial content (log cfu/g) of A stored for 3 days in DS was 6.7 (which represented an increase of 1 log cycle compared with day zero), but was 5.50 in B, 3.23 in C, 4.90 in D, 2.40 in E and 1.77 in F, the latter similar to counts at day zero. The degree of microbial contamination of DS and TS followed the order F > E > D > C > B > A in flounder, and F > E > C > D > B > A in rockfish. In general the hardness and chewiness of TS was less than for DS. While the effect of CA on TS texture was not significant in flounder, the effect showed in rockfish. For DS, the appearance in B, C and D was relatively good, as was freshness. Fishiness of flavor was in the order A > B > F > E > D > C. Overall acceptability of flounder and rockfish treated with C was better than treatment with the other washing agents. For TS the appearance of flounder and rockfish were good in B and C. The freshness of flounder and rockfish were in the order of D > C > B > A > E > F and D > C > B > A > E > F, respectively. Fishiness of the flavor of sliced raw fish was lowest in D, which also provided the best overall acceptability.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.34-38
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• 2000

In this paper, interference effects between NGSO and HAPS in the feeder link have been simulated and analyzed by means of calculating excess time percent and duration below the C/I protection ratio. As the results, in the case of HAPS interference into NGSO, it can be obtained that the lowest C/I values are 27.42dB in 50km and 12.73dB in 20Km of HAPS altitudes, respectively. And in the case of NGSO interference into HAPS, it can be obtained that the lowest C/I values are 13.94dB and 10.42dB respectively. HAPS system has more interference reception from other systems or effects more interference into other systems as its altitude is lower. Also, the lowest C/I values are appeared at difference time with its altitude.