• Journal of Microbiology
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• 제34권4호
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• pp.300-304
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• 1996

To define the effects of zooplankton and phytoplankton to bacteria, bacterial numbers, frequency of dividing cells (FDC) and size distribution were performed with image analysis in the surface layer of Lake Soyang. In August 1992, when Anabaena was blooming, the bacterial number increased at daytime. Bacterial numbers and FDC value had a negative correlation (r = 0.83, P < 0.01). Bacterial size spectrums were dynamically changed during the day and night, especially the small bacteria less than $0.5\;{\mu}m^3$. Meanwhile, in October, after the bloom, the bacterial number was only one third of that in August, even though the FDC was higher than that in August. The bacterial numbers of small size class dropped at 13:00. But the size spectrums were relatively constant during the night time. These results suggest that the bacterial growth was tightly coupled with phytoplankton during Anabaena bloom. And after the bloom, the bacterial number was controlled grazing activity of zooplankton at daytime.

• 대한지구과학교육학회지
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• 제8권2호
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• pp.152-163
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• 2015

In this study, to raise the interest and curiosity of students and at the same time to learn science concepts meaningfully for students, the teaching and learning program was developed by applying the Frayer model. The purpose of this study was to find out the Effect of Elementary Science Teaching Program with Frayer model on Learning Motive and Learning Achievement. To this end, the 6th grade classroom of A-elementary school located in Seogwipo-city was selected the experimental group (26 patients). And the other 6th grade classroom in the same school was selected to the comparative group (27 patients). The experimental group was conducted applying the Frayer model. Comparison group has been conducted lesson program in accordance with the general science class teacher guide. Was through a pre-test of science learning motivation and academic achievement level can be assumed in the same group. After completing the experimental treatment by conducting a post-mortem examination was statistically validated. In this study, the following conclusions were obtained. First, elementary science class which applied Frayer model had the effect of to improve the scientific motivation. In particular, attention (p <.01), association (p <.01), confidence (p <.01) in the experimental group were higher than the scores of the comparative group, the difference was significant. Second, the Frayer model applied to elementary science class had a significant effect on improving science achievement. The experimental group which applied Frayer model was higher than the comparative group in science achievement post-test comparison. Between the groups showed a significant difference between the two groups (p <.01). The above findings, Elementary science class which applied Frayer model can be concluded to be effective in science and science achievement motivation. Therefore, applying the Frayer model of elementary science class could be useful in science teaching and learning methods. In addition, when it is determined through the previous study, applying the Frayer model classes will be able to derive a meaningful learning also subjected to a number of fields and areas.

• 대한소아치과학회지
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• 제29권4호
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• pp.568-573
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• 2002

교정치료를 받는 어린이들의 우식활성에 관여하는 요인들을 규명하고자, 고정성 및 가철성 교정장치를 구강에 장착하고 있는 어린이 50명을 대상으로 Cariostat 우식활성검사를 실시하고 우식활성요인으로서 성별, 연령, 교정장치 장착기간, 장치의 종류, 장치를 장착한 부위, Angle씨 부정교합 분류, 우식경험치 수 등의 요인을 조사하였다. 연구대상의 Cariostat 검사성적은 0점과 3점이 각각 1명(2%)씩 있었고 1점이 22명(44%), 2점이 26명(52%)이었다. 저우식활성군의 평균 연령은 9.96세 고우식활성군의 평균 연령은 11.56세로서 두 군간의 차이가 유의하였다(P<0.01). 구강내 교정장치 장착기간은 저우식활성군이 16.13개월, 고우식활성군이 20.48개월로서 고우식활성군의 장착기간이 길었으나 유의한 차이는 없었다(P>0.05). 가철성 장치만 장착한 경우에 비해 고정성 장치를 장착한 경우에서 우식활성이 더 높았다(P<0.01). 상악에만 장착한 경우에 비해 상악과 하악에 다 장착한 경우에서 우식활성이 더 높은 분포를 보였으나 통계학적 유의성은 없었다(P>0.05). Angle씨 I 급 부정교합의 경우에 우식활성이 높고 III 급 부정교합의 경우에 우식활성이 낮은 분포를 보였으나 통계학적 유의성은 없었다(P>0.05). 우식경험치 수는 저우식활성군이 1.83개, 고우식활성군이 1.41개이었으나 유의한 차이는 아니었고(P>0.05) 전체 평균은 1.60개이었다.

• Kyungpook Mathematical Journal
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• 제43권4호
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• pp.489-494
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• 2003

In this paper, we first establish an interesting theorem involving the $\bar{H}$-function introduced by Inayat-Hussain ([7], [8]). The convergence and existence condition, basic properties of this function were given by Buschman and Srivastava ([2]). Next, we obtain certain new integrals and an expansion formula by the application of our theorem. On account of the most general nature of the functions involved herein, our main findings are capable of yielding a large number of new, interesting and useful integrals, expansion formulae involving simple special functions and polynomials as their special cases. A known special case of our main theorem in also given ([11]).

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제16권2호
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• pp.199-212
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• 2009

We investigate the multiplicity of the nontrivial periodic solutions for a class of the system of the nonlinear suspension bridge equations with Dirichlet boundary condition and periodic condition. We show that the system has at least two nontrivial periodic solutions by the abstract version of the critical point theory on the manifold with boundary. We investigate the geometry of the sublevel sets of the corresponding functional of the system and the topology of the sublevel sets. Since the functional is strongly indefinite, we use the notion of the suitable version of the Palais-Smale condition.

• The Korean Journal of Ecology
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• 제14권3호
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• pp.305-316
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• 1991

Growth hadit and demograph in a mature population of polygonatum and polygonatum humile in kanghwa island were studied for two growing seasons. Shoots of two species emerged early spring from the growing apices of the underdground rhizomes which had persisted for up to 1~5 year.after flowering, the ramets produced two rhizome buds at the shoot base. Bacause of the apical dominance in the rhizome system, a new rhizome was developed from only one bud, an actual bud,and the other latent buds were suppressed sothat remained dormant. The latent dud produced a new rhizome only when the actual dud was severed by the herbivores or by the physical obstacles. Therefore, the ramet number is not increased by the new rhizome from the latent bud. however, new ramets dould sometimes grow from latent buds which had been produced more than a year ago. Production of these ramets was main means increasing the ramet numbew and widening the potential zone of exploitation. Changes in size class of each ramet were noyiceable after a tear in small size-classes. Small ramets replaced themselves with larger-sized ramet, while large ramets with similar-sized or smallar-sized ramets. ramet numbers were average 0.82and 1.14 times of those fromthe previous year inp. involucratum and p. humile, though there was between-site variation. Almost all the ramets in the quadrats were alive during the growing season. when the entire rhizome systems were excavater next spring, there were many rhizomesegments without shoots, especially in p. involucratum. therefore, the drcrease of ramet number in p. involucratum in probably due to the climatic factors of winter.

• 응용통계연구
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• 제15권2호
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• pp.367-379
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• 2002

본 연구에서는 부분이면교배에서 p개의 근교계통의 일반조합능력을 비교하기 위한 불완비 블록계획을 구성하는 방법을 제시한다. 부분이면 블록계획은 블록의 크기가 2 이면서 m개의 동반분류를 갖는 부분 균형 불완비 블록계획과균형 불완비 블록계획을 이용하여 구성한다. 또한, p $\leq$ 24일 때 이러한 방법으로 구성되는 블록계획의 효율성을 표로 제시한다.

• ETRI Journal
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• 제28권6호
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• pp.745-760
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• 2006

In this paper, we particularly deal with no $F_p$-rational two-torsion elliptic curves, where $F_p$ is the prime field of the characteristic p. First we introduce a shift product-based polynomial transform. Then, we show that the parities of (#E - 1)/2 and (#E' - 1)/2 are reciprocal to each other, where #E and #E' are the orders of the two candidate curves obtained at the last step of complex multiplication (CM)-based algorithm. Based on this property, we propose a method to check the parity by using the shift product-based polynomial transform. For a 160 bits prime number as the characteristic, the proposed method carries out the parity check 25 or more times faster than the conventional checking method when 4 divides the characteristic minus 1. Finally, this paper shows that the proposed method can make CM-based algorithm that looks up a table of precomputed class polynomials more than 10 percent faster.

• 전자공학회논문지CI
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• 제47권6호
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• pp.28-39
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• 2010

본 논문은 IEEE 802.11p에 기반한 CSMA의 미디어 접근 제어로서, 경쟁 차량단말기(OnBord Unit, OBU)의 증가에 따른 전송 지연(transmission delay)과 감소(data throughput decrease) 문제를 해결하고자 한다. 경쟁 기반의 전송매체에서는 OBU 증가에 따라 충돌 확률이 높아진다. 이러한 미디엄 계층의 성능 향상을 위해 교통량과 데이터 종류를 고려하여 접속 단말기의 개별 충돌 윈도(Contention Windows, CW)를 동적으로 조절하는 EDCA(Enhanced Distributed Channel Access)를 제안하였다. EDCA는 채널별 서비스 차별화를 위해 네 개의 클래스를 AC(Access Category)마다 고정된 최소 경쟁 윈도우(CWmin) 값과 최대 경쟁 윈도우(CWmax) 값을 적용한다. EDCA는 트래픽 특성별로 구분되어 AC 간의 차별화를 보장하지만, IEEE 802.11p 에 구성된 채널별 특성과 네트워크 상태를 보장하지 않기 때문에, 짧은 채널 서비스별 혼잡에 따른 충돌 발생을 능동적으로 대처할 수 없다. 이에 따른 해결방안으로 CWminAS(CWmin Adaptation Scheme)와 ACATICT(Adaptive Contention window Adjustment Technique based on Individual Class Traffic)가 능동적인 CW의 제어 기법으로 제시되었다. 선행연구는 개별 AC 값에 따라 발생하는 충돌 확률을 고려하지 않거나 단일 채널 기반의 개별 AC 값만 고려하고, IEEE 802.11p의 채널별 요구 사항과 이에 따른 충돌 확률을 반영하지 않았다. 본 연구는 이전 서비스 구간에서 OBU 경쟁에 따라 발생하는 충돌 횟수와 현재 무선망의 혼잡을 고려하여, 다음 채널의 CW를 능동적으로 제어하는 기법으로 ACCW(Adaptive Control of Contention windows in considering the WAVE situation)를 제안한다.

• 한국통신학회논문지
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• 제27권1A호
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• pp.42-50
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• 2002

본 논문에서는 소수 p에 대해 이상적인 자기상관특성을 갖는 p진 d-동차시퀀스를 발생시키기 위한 생성방법을 제안하고 Helleseth와 Kumar, Martinsen이 찾아낸 3진 d-동차시퀀스를 이용한 이상적인 자기상관특성을 갖는 3진 d-동차시퀀스를 소개하였다. p진 확장시퀀스(기하시퀀스의 특별한 경우)의 방생 방법과 p진 d-동차시퀀스의 발생방법을 조합하면 이진과 p진 확장 시퀀스, d-동차시퀀스 모두를 포함하는 매우 일반적인 행태의 이상적인 자기상관 특성을 갖는 p진 통합(확장 d-동차)시퀀스의 발생 방법을 제안하였다. 또한, Helleseth와 Kumar, Martinsen이 발견한 이상적인 자기상관특성을 갖는 3진 시퀀스로부터, 이상적인 자기상관특성을 갖는 3진 통합시퀀스를 생성하였다.