• 대한수학회논문집
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• 제38권4호
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• pp.1309-1320
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• 2023

Let f : X → Y be a map between simply connected CW-complexes of finite type with X finite. In this paper, we prove that the rational cohomology of mapping spaces map(X, Y ; f) contains a polynomial algebra over a generator of degree N, where N = max{i, π_i(Y)⊗ℚ ≠ 0} is an even number. Moreover, we are interested in determining the rational homotopy type of map(𝕊ⁿ, ℂP^m; f) and we deduce its rational cohomology as a consequence. The paper ends with a brief discussion about the realization problem of mapping spaces.

• Archives of Pharmacal Research
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• 제17권6호
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• pp.438-442
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• 1994

Antimicrobial activity of GL (the aqueous extract from the carpophores of Ganoderma lucidum ($F_RK_{KARST}$) was tested in vitro aginst Gram positive and Gram negative bacteria by serial broth dilution method, and the antimicrobial activity was expressed by minimal inhibitory concentration (MIC). Among fifteeen species of bacteria tested, the natimicrobial activity of GL was of antimicrobial combinations of GL with four kinds of antibiotics (ampicilin, cefazolin, oxytet-racycline and chloramphenicol), the fractional inhibitory concentraction index (FICI) was determined by checkerboard assy for each stain. The antimicrobial combinations of GL with four antibiotics resulted in additive effect in most instances, synergism in two instances, and antagonism in two instances. Synergism was obversed when GL was combined with cefazolin against Bacillus subtilis and Klebsiella oxytoca.

• 한국군사과학기술학회지
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• 제2권2호
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• pp.251-260
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• 1999

The stiffness of joint parts in the finite element beam model are corrected by the direct comparison between the modal test and analysis model. The corrected stiffness are reviewed according to the boundary conditions of modal testing. For the improved modal test/analysis correction, more modes measured than acceleration sensors are used to make a minimal order system model. In addition, the initial F.E. model is reduced to the degrees of freedom of a minimal order system model, keeping the dynamics of the initial model. Finally, for the parametric correction of the reduced model, the submatrices are used to model the initially assumed stiffness.

• 대한수학회지
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• 제59권1호
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• pp.105-127
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• 2022

It is known that the maximal invariant set of a continuous iterative dynamical system in a compact Hausdorff space is equal to the intersection of its forward image sets, which we will call the first minimal image set. In this article, we investigate the corresponding relation for a class of discontinuous self maps that are on the verge of continuity, or topologically almost continuous endomorphisms. We prove that the iterative dynamics of a topologically almost continuous endomorphisms yields a chain of minimal image sets that attains a unique transfinite length, which we call the maximal invariance order, as it stabilizes itself at the maximal invariant set. We prove the converse, too. Given ordinal number ξ, there exists a topologically almost continuous endomorphism f on a compact Hausdorff space X with the maximal invariance order ξ. We also discuss some further results regarding the maximal invariance order as more layers of topological restrictions are added.

• 말소리와 음성과학
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• 제5권4호
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• pp.129-136
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• 2013

This study investigated how acoustic characteristics (i.e., duration, F1, F2) of English high front vowels /i, ɪ/ are modulated by boundary- and prominence-induced strengthening in native vs. non-native (Korean) speech production. The study also examined how the durational difference in vowels due to the voicing of a following consonant (i.e., voiced vs. voiceless) is modified by prosodic strengthening in two different (native vs. non-native) speaker groups. Five native speakers of Canadian English and eight Korean learners of English (intermediate-advanced level) produced 8 minimal pairs with the CVC sequence (e.g., 'beat'-'bit') in varying prosodic contexts. Native speakers distinguished the two vowels in terms of duration, F1, and F2, whereas non-native speakers only showed durational differences. The two groups were similar in that they maximally distinguished the two vowels when the vowels were accented (F2, duration), while neither group showed boundary-induced strengthening in any of the three measurements. The durational differences due to the voicing of the following consonant were also maximized when accented. The results are discussed further in terms of phonetics-prosody interface in L2 production.

• 한국콘텐츠학회논문지
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• 제10권6호
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• pp.373-377
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• 2010

영어의 경우는 모음포만트 분석이 질적이나 양적으로 이미 오래전부터 많이 이루어져 왔다. 그러나 한국어 모음이 음향음성학적으로는 제대로 분석되지 않고 있는 실정이다. 본 연구의 목적은 한국어 모음에 대한 음향음성학적 측면에서 정량적으로 충분한 자료 확보를 위한 과정의 일환으로 정상 남자 20대와 30대를 대상으로 한국어 모음의 음향학적 측면에서 정량적 자료를 얻고자 하였다. 한국어 표준어를 산출하는 20~30대의 남자 총 31명을 대상으로 기본 5 모음 인 /아, 에(애), 이, 오, 우/를 3회 반복산출한 것을 Cool edit에 녹음하여 MATLAB음향분석 프로그램을 이용하여 모음의 F1, F2, F3, F4를 구하였다. F1과 F2 모두에서 본 연구의 모음 포만트가 선행연구보다 전반적으로 낮은 경향을 보였으나 전체적인 패턴은 매우 유사하였다. 연령별, 어음재료에 따른 한국어 모음 자료들에 대한 연구가 더 요구될 것으로 사료된다.

• Annals of Clinical Neurophysiology
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• 제19권1호
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• pp.13-19
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• 2017

Background: Median F-wave latencies are physiologically shorter than ulnar latencies, but they are often longer relative to ulnar latencies in carpal tunnel syndrome (CTS). This study aimed to investigate the value of absolute F-waves and relative latency changes compared to ulnar latencies in the diagnosis of CTS. Methods: F-wave latencies of median and ulnar nerves in 339 hands from 339 patients with CTS and 60 hands from 60 control subjects were investigated. Mean F-wave minimal latencies of median and ulnar nerves were compared between groups. Patients were further divided into subgroups based on Canterbury grading and then analyzed using F-wave latency differences (FWLD) and F-wave ratio (FWR). Results: Of 339 hands in the CTS group, 236 hands exhibited F-wave inversion based on the FWLD criterion and 277 hands had F-wave inversion based on the FWR criterion. F-wave inversion had a sensitivity of 81.7% using the FWR criterion to diagnose CTS. The mean FWLD and FWR were significantly greater in all patient subgroups compared to the control group (p < 0.001). In addition, mean FWLD and FWR showed significant correlations (r = -0.683 and r = 0.674, respectively, p < 0.001) with disease severity. Conclusions: F-wave studies are effective supplementary diagnostic tools comparing to other standard electrophysiologic criteria for screening patients with CTS.

• 한국환경과학회지
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• 제24권12호
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• pp.1591-1600
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• 2015

The response of the freshwater microalga, Chlorella vulgaris, to heavy metal stress was examined based on chlorophyll fluorescence analysis to assess the toxic effects of heavy metals in freshwater ecosystems. When toxic effects were analyzed using regular chlorophyll fluorescence analysis, photosystem II activity($F_v/F_m$) decreased significantly when exposed to $Cu^{2+}$ and $Hg^{2+}$ for 12 h, and decreased in the order of $Hg^{2+}>Cu^{2+}>Cd^{2+}>Ni^{2+}$ when exposed for 24h. The effective photochemical quantum yield(${\phi}{\prime}_{PSII}$), chlorophyll fluorescence decrease ratio($R_{Fd}$), minimal fluorescence yield($F_o$), and non-photochemical quenching(NPQ), but not photochemical quenching(qP), responded sensitively to $Hg^{2+}$, $Cu^{2+}$, and $Cd^{2+}$. These results suggest that $F_v/F_m$, as well as ${\phi}{\prime}_{PSII}$, $R_{Fd}$, $F_o$, and NPQ could be used to assess the effects of heavy metal ions in freshwater ecosystems. However, because many types of heavy metal ions and toxic compounds co-occur under natural conditions, it is difficult to assess heavy metal toxicity in freshwater ecosystems. When Chlorella was exposed to heavy metal ions for 12 or 24h, $F_v/F_m$ and maximal fluorescence yield($F_m$) changed in response to $Hg^{2+}$ and $Cu^{2+}$ based on image analysis. However, assessing quantitatively the toxic effects of several heavy metal ions is challenging.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 2005년도 제44차 추계학술대회 및 총회
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• pp.328.2-328.2
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• 2005

• 호남수학학술지
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• 제36권2호
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• pp.387-398
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• 2014

In this paper, we give a structure theorem for a class of Gorenstein ideal of grade 4 which is the sum of an almost complete intersection of grade 3 and a Gorenstein ideal of grade 3 geometrically linked by a regular sequence. We also present the Hilbert function of a Gorenstein ideal of grade 4 induced by a Gorenstein matrix f.