• 대한수학회보
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• 제49권2호
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• pp.395-409
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• 2012

In the study of homology cobordisms, knot concordance and link concordance, the following technical problem arises frequently: let ${\pi}$ be a group and let M ${\rightarrow}$ N be a homomorphism between projective $\mathbb{Z}[{\pi}]$-modules such that $\mathbb{Z}_p\;{\otimes}_{\mathbb{Z}[{\pi}]}M{\rightarrow}\mathbb{Z}_p{\otimes}_{\mathbb{Z}[{\pi}]}\;N$ is injective; for which other right $\mathbb{Z}[{\pi}]$-modules V is the induced map $V{\otimes}_{\mathbb{Z}[{\pi}]}\;M{\rightarrow}\;V{\otimes}_{\mathbb{Z}[{\pi}]}\;N$ also injective? Our main theorem gives a new criterion which combines and generalizes many previous results.

• The Plant Pathology Journal
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• 제16권2호
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• pp.105-109
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• 2000

The Pi-b is the rice gene conferring race specific resistance to the blast fungus Magnaporthe grisea race having a corresponding avirulence gene, AVR-Pi-b. All resistant cultivars have two copies of the Pi-b gene, but susceptible cultivars have a single copy of the gene. About 1 Kbp insertion sequence was detected in the open reading frame of the Pi-b gene from the susceptible cv. Nipponbare. The nature of insertion sequence was identified as a solo long terminal repeat (LTR) of new rice Tyl-copia-like retrotransposon. LTR was widely distributed in the rice genome. Various types of different patterns of restriction fragment length polymorphism of LTR were detected in indica cultivars, whereas a single type was detected from japonica cultivars. The insertion of LTR sequence in the Pi-b gene in the susceptible cultivar suggested that retrotransposon-mediated insertional mutation might played an important role in the resistance breakdown as well as evolution of resistance genes in rice.

• 전자공학회논문지B
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• 제30B권5호
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• pp.109-119
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• 1993

To improve limitations of fuzzy PI controllers especially when applied to systems of order higher than one, we propose a fuzzy PI controller that takes out appropriate amounts of accumulated control input according to fuzzily described situations in addition to the calculation of incremental control input as in the case of conventional fuzzy PI controllers. The structure of the proposed controller was motivated by the characteristics of fuzzy PI controller that it generally gives inevitable overshoot when one tries to reduce rise time of the response especially when a system of order higher than one is under consideration. Since the undesirable characteristics of the fuzzy PI controller is caused by integrator of the controller, even though the integrator is introduced to overcome steady state error of response, we propose a controller that fuzzily clears out integrated quantities according to situation to give reduced rise time as well as small overshoots. To show the usefulness of the proposed controller, it is applied in simulations to such systems as are difficult to stabilize or difficult to get satisfactory responses by conventional fuzzy PI controllers.

• 한국전기전자재료학회논문지
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• 제14권2호
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• pp.130-132
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• 2001

The mechanisms of pretilt angle generation in nematic liquid crystal (NLC) with negative dielectric anisotropy on a rubbed polyimide (PI) surface for homeotropic alignment were studied. The pretilt angle of negative type NLC was smaller than that of the positive type NLC for all rubbing strength regions on the rubbed PI surface. The pretilt angle generated in NLC does not attributable to steric interaction between the fluorine moiety of NLC and the polymer surface on the rubbed PI surface. Consequently, the mechanism of the pretilt angle generation for homeotropic alignment is different from the one for homogeneous alignment.

• The Korean Journal of Physiology and Pharmacology
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• 제4권6호
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• pp.507-513
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• 2000

ErbB3/HER3 is a cell surface receptor which belongs to the ErbB/HER subfamily of receptor protein tyrosine kinases. When expressed in NIH/3T3 cells, ErbB3 can form heterodimeric coreceptor with endogenous ErbB2. Among known intracellular effectors of the ErbB2/ErbB3 are mitogen-activated protein kinase (MAPK) and phosphoinositide (PI) 3-kinase. In the present study, we studied relative contributions of above two distinct signaling pathways to the heregulin-induced mitogenic response via activated ErbB3. For this, clonal NIH-3T3 cell lines expressing wild-type ErbB3 and ErbB3 mutants were stimulated with $heregulin{\beta}_1$. While cyclin D1 level was markedly high and further increased by treatment of heregulin in cells expressing wild-type ErbB3, the elimination of either Shc binding or PI 3-kinase binding lowered both levels. This result was supported by the reduction of cyclin $D_1$ expression by preteatment with MAPK kinase inhibitor or PI 3-kinase inhibitor before stimulation with heregulin. In accordance with the cyclin $D_1$ expression, elimination of either Shc binding or PI 3-kinase binding reduced the heregulin-induced DNA synthesis and cell growth rate. Our results obtained by the comparison of wild-type and ErbB3 mutants indicate that the full induction of the cell cycle progression through $G_1/S$ phase by ErbB3 activation is dependent on both Shc/MAPK and PI 3-kinase signal transduction pathways.

• 대한한방내과학회지
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• 제30권3호
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• pp.550-557
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• 2009

Objectives : The purpose of this study was to investigate the possibility of Bi-Su as a pattern identification (PI) index in stroke patients. Methods : The subjects were 424 hospitalized stroke patients within 1 month from onset and diagnosed with the same PI subtypes (dampness & phlegm, qi deficiency, fire & heat, eum deficiency, and blood stasis) by agreement of two clinical experts. Bi-Su type is a kind of body shape (Bi : fat, Su : lean). Bi-Su type and degree (Bi-Su score) were decided by clinical expert. Body mass index (BMI) and waist-hip ratio (WHR) were used as an obesity index. Correlation analysis between Bi-Su score and obesity index (Spearman) and variance analysis for Bi-Su score, BMI, and WHR among PI subtypes (ANOVA) and sex were carried out. Results : While there was partial correlation between Bi-Su type and BMI($r^2$=0.634, p<0.001), the distribution of the BMI group based on the Bi-Su group showed the broadest range. The Bi-Su score in the dampness & phlegm group was higher than in the other groups (p<0.001). BMI in the dampness & phlegm groups was also higher but the BMI differences among PI subtypes was low (p=0.002). The Bi-Su score in the dampness & phlegm group was similar in both sexes, although the hand score in the eum deficiency group was the lowest, especially in males. Conclusions : Although BMI is not an objective enough tool for evaluating Bi-Su type, Bi-Su type is more appropriate than BMI as PI index. Therefore Bi-Su type could be used as one of the PI indices for dampness & phlegm or eum deficiency group in stroke patients.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.67-70
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• 2003

The control of tilt angle for nematic liquid crystal (NLC) with negative and positive dielectric anisotropy on the rubbed homeotropic polyimide (PI) using baking method by hot plate equipment was investigated. LC tilt angle decreased with increasing baking temperature and time. Especially, the low LC tilt angle of positive type NLC ($\Delta\varepsilon$ >0) on the rubbed homeotropic PI surface by increasing temperature and time was measured. The tilt angle of positive type NLC ($\Delta\varepsilon$ >0) is smaller than that of the negative type ($\Delta\varepsilon$ >0) on rubbed PI with increasing baking temperature and time. We consider that the tilt angle of NLC is decreased due to increasing the steric interaction between horizon component of permittivity $\varepsilon$ = of NLC and the stress of polymer side chain by high temperature.

• 전자공학회논문지B
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• 제30B권12호
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• pp.87-97
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• 1993

To improve the limitation of fuzzy PI controller when is applied to systems of order higher than one, a fuzzy PI controller that fuzzily resets or amplifies the accumulated control input according to fuzzy rules defined on (error, change of error) space is proposed. The proposed controller structure was motivated by the characteristics of fuzzy PI controller that it generally gives unevitable large overshoot in trial of reducing rise time of response especially when a system of order higher than one is considered. Based on the observation that the undesirable characteristics of the fuzzy PI controller is caused by integrating control input excessively, even though the integrator is introduced to overcome steady state error, we propose a controller that clear out or doubles integrated control input in a fuzzy manner according to the situation to reduce rise time as well as overshoot. To show the usefulness of the proposed controller, it is applied to the systems that are difficult to stabilize or difficult to get satisfactory response by conventional fuzzy PI controllers.

• Macromolecular Research
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• 제12권3호
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• pp.251-257
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• 2004

The nature of the nematic liquid crystal (LC) alignment induced by the rubbed polyimide (PI) alignment layers (ALs) and the electro-optical (EO) properties of the LC cells are expected to depend on the chemical and physical features of the PI. By employing five pyromellitic dianhydride (PMDA)-type PIs having different functionalities, we have studied the effects of the PI's structure and chemistry on the alignment characteristics and the cell's EO properties. Increasing the flexibility of the PI increases the pretilt angle and tends to improve the alignment stability. On the other hand, the rigid, fluorinated PI displays poor stability for LCs and induces a less stable/uniform LC alignment and, subsequently, a small pre tilt angle. It also transpired that fluorination of the PI deteriorated the voltage-transmittance characteristics and the voltage holding ratio; increasing the flexibility of the PI structure improves these EO properties. The finding that the qualitative trends for the PI's functionalities are similar for both the alignment and EO properties suggests that the EO properties are closely related to the alignment characteristics, which are determined by short-range interactions between LC and PI molecules.

• 폴리머
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• 제34권4호
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• pp.376-380
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• 2010

분자내 전하이동(intramolecular charge transfer, ICT)이 가능한 도너-$\pi$-억셉터(D-$\pi$-A)타입의 발색단 을 근간으로 한 폴리머를 신규 합성하였다. 이 폴리머는 UV-visible spectra 측정결과 용액 상태에서 뿐만 아니라 고체박막 상태에서도 카르보닐기(carbonyl group)에서 기인하는 흡수와 함께 ICT에 의한 장파장 영역에서의 흡수가 관 찰되었다. $Eu^{3+}$ 이온의 첨가에 의해 장파장영역에서 일어나는 흡수의 적색이동(red shift)을 유도하였으며, 더불어 용 액과 박막의 색상도 황색에서 적색으로 변화하는 것이 관찰되었다. 합성된 고분자의 형태 및 유기 용매에 대한 용해도 는 가교제의 함량에 따라 다양한 특성을 나타내었다. 또한, 첨가된 가교제의 함량과 $Eu^{3+}$ 이온의 첨가는 성막 특성의 향상을 유도하였다.