• Composites Research
• /
• 제19권6호
• /
• pp.16-22
• /
• 2006

다양한 조건 하에서 최상의 관통 특성을 발휘하기 위한 최적 조건에 대해 연구하였다. 섬유 종횡비(AR: 섬유 길이/섬유 직경), 계면 조건 그리고 섬유 함유량을 관통 저항력과 마찰력에 지대한 영향을 미치는 변수들로 고려하였다. 단섬유 강화고무의 관통 저항력은 기지에 비해 최대 3.4배 증가하였다. 동일한 섬유 종횡비와 섬유 함유량에서 계면 조건이 우수할수록 더 높은 관통 저항력을 보였다. 기지와 섬유 종횡비가 155이하인 일부 단섬유 강화고무의 마찰력은 존재치 않았다. 우수한 계면과 높은 섬유 종횡비를 갖는 단섬유 강화고무의 마찰력은 기지의 관통 저항력보다도 더 높았다. 전체적으로 계면 조건과 섬유 종횡비 그리고 섬유 함유량이 단섬유 강화고무의 관통 특성에 지대한 영향이 미침을 확인하였다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1996년도 하계학술대회 논문집 A
• /
• pp.372-375
• /
• 1996

In this paper, a new active interphase reactor for twelve-pulse diode rectifiers is proposed. The proposed system draws near sinusoidal currents from the utility. In this scheme, a low kVA(0.02 $P_o$ (PU)) active current source injects a triangular current into an interphase reactor of a twelve-pulse diode rectifier. The modification results in near sinusoidal input current with less than 1% THD. Experimental results are provided from a 208V, 10kVA rectifier system.

• 대한전자공학회논문지
• /
• 제24권4호
• /
• pp.658-666
• /
• 1987

In this paper, a new mehtod of reducing harmonics that involved in input AC line currents or in output DC voltage of the converter system is presented. which is due mainly to the quipment of 2-3 switching taps on interphase reactor. In case that the 3 tap method is applicable to conventional 12 pulse converter, it could not bring to an effect of reducing harmonics under firing angle 15\ulcorner To solve these problems, 24 pulse or 36 pulse converter is controlled by microprocessor. The former is performed in 2 tap method when \ulcorneris less than 15\ulcorner the latter in 3 tap method when it is more then 15\ulcorner Therefore the originality of this paper liea in microprocessor based equipment of the 2-3 switching taps on interphase reactor. I applied this method to the 12 pulse converter, and proved validity of that theoretically and experimentally.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
• /
• pp.276-280
• /
• 1998

This paper proposes a harmonic a harmonic reduction technique of the parallel-connected twelve-pulse thyristor rectifiers. The proposed system is an improvement over the diode rectifier system with an active interphase reactor [2]. In this scheme, a low KVA (0.15 Po (PU) ) active current source injects a triangular current into an interphase reactor of a twelve-pulse thyristor rectifier along the phase delay angle. The current injection results in near sinusoidal input current with less than 1% THD. Detailed analysis of the proposed scheme along scheme along with design equations is illustrated. Simulation results verify the concept.

• 생약학회지
• /
• 제23권2호
• /
• pp.73-76
• /
• 1992

Effect of various fractions prepared from the methanol extract of Ixeris sonchifolia and flavonoids isolated from the extract on hypercholesterolemic mice were examined. When various fractions $(CHCl_3,\;Interphase,\;EtOAc,\;n-BuOH\;and\;H_2O)$were administered to mice, the Interphase material produced a significant activity. Total cholesterol level in the Interphase material-treated group given doses of 25 and 50mg was decreased significantly by as much as 16% and 30%, respectively. Among the isolated flavonoids, cynaroside caused a significant hypocholesterolemic activity.

• 한국세라믹학회지
• /
• 제53권1호
• /
• pp.87-92
• /
• 2016

Due to its stability at high temperature and its layered structure, $Ti_3SiC_2$ MAX phase was considered to the interphase of $SiC_f/SiC$ composite. In this study, $Ti_3SiC_2$ MAX phase powder was deposited on SiC fiber via the electrophoretic deposition (EPD) method. The Zeta potential of the $Ti_3SiC_2$ suspension with and without polyethyleneimine as a dispersant was measured to determine the conditions of the EPD experiments. Using a suspension with 0.03 wt.% ball milled $Ti_3SiC_2$ powder and 0.3 wt.% PEI, $Ti_3SiC_2$ MAX phase was successfully coated on SiC fiber with an EPD voltage of 10 V for 2 h. Most of the coated $Ti_3SiC_2$ powders are composed of spherical particles. Part of the $Ti_3SiC_2$ powders that are platelet shaped are oriented parallel to the SiC fiber surface. From these results we expect that $Ti_3SiC_2$ can be applied to the interphase of $SiC_f/SiC$ composites.

• Journal of Microbiology and Biotechnology
• /
• 제27권1호
• /
• pp.130-140
• /
• 2017

It is vital to understand the changing characteristics of interphase microbial communities and interspecies synergism during the fermentation of Chinese liquors. In this study, microbial communities in the three indispensable phases (pit mud, zaopei, and huangshui) of Luzhou-flavored liquor manufacturing pits and their shifts during cellars use were first investigated by polyphasic culture-independent approaches. The archaeal and eubacterial communities in the three phases were quantitatively assessed by combined phospholipid ether lipids/phospholipid fatty acid analysis and fluorescence in situ hybridization. In addition, qualitative information regarding the microbial community was analyzed by PCR-denaturing gradient gel electrophoresis. Results suggested that the interphase microbial community profiles were quite different, and the proportions of specific microbial groups evolved gradually. Anaerobic bacteria and gram-positive bacteria were dominant and their numbers were higher in pit mud ($10^9$ cells/g) than in huangshui ($10^7$ cells/ml) and zaopei ($10^7$ cells/g). Hydrogenotrophic methanogenic archaea were the dominant archaea, and their proportions were virtually unchanged in pit mud (around 65%), whereas they first increased and then decreased in zaopei (59%-82%-47%) and increased with pit age in huangshui (82%-92%). Interactions between microbial communities, especially between eubacteria and methanogens, played a key role in the formation of favorable niches for liquor fermentation. Furthermore, daqu (an essential saccharifying and fermentative agent) and metabolic regulation parameters greatly affected the microbial community.

• Composites Research
• /
• 제32권5호
• /
• pp.270-278
• /
• 2019

본 연구에서는 섬유, 기지 및 계면으로 구성된 단방향 복합재료의 대표체적요소를 이용해서 가로방향 기계적 물성을 계면 특성 변화에 따라 예측하고 시험결과에 맞춰 계면의 특성의 보정을 실시하였다. 섬유와 기지로 모델링 된 기존의 대표체적요소는 섬유 길이방향 기계적 물성에 대해 예측 정확도가 높으나 가로방향에 대하여 어느 정도의 편차를 보인다. 따라서, 이런 차이를 보완하기 위해 계면 영역을 도입하였고, 계면의 두께, 탄성 물성과 강도 파라미터에 따라 기계적 물성을 보정하여 복합재료 대표체적요소를 통한 예측의 정확도를 향상시켰다. 그 결과, 복합재료 대표체적요소의 길이방향 물성의 정확도는 유지한 채 가로방향 강성 및 강도의 정확도가 향상됨을 확인하였다.

• Applied Microscopy
• /
• 제24권3호
• /
• pp.78-86
• /
• 1994

A TEM study on proeutectoid ${\alpha}$ reaction at sub-eutectoid temperatures has been made in hypoeutectoid Ti-3.gw/o Co and Ti-5.2w/o Fe alloys. Widmanstatten ${\alpha}$ plates were formed in both alloys within the ${\beta}$ matrix with some modification of degenerate forms. These degenerate plates were formed by the sympathetic nucleation of ${\alpha}$ plates at ${\alpha}:{\beta}$ interphase boundaries. Three types of sympathetic nucleation, i.e., edge-to-edge, face-to-edge, face-to-face, were found in both alloys. The edge-to-edge sympathetically nucleated crystals formed a low-angle boundary between two crystals. The ${\alpha}:{\beta}$ interphase boundaries were found to be partially coherent interfaces which consist of regularly spaced misfit dislocations. The growth of these interphase boundaries were accomplished by the lateral movement of growth ledges. The intersection points of two ${\alpha}$ plates or the low angle boundaries which had formed by edge-to-edge sympathetic nucleation played a role as the potential sources of growth ledges during the growth of plate. The interfacial structures and the spatial morphologies of the degenerate proeutectoid ${\alpha}$ plates would be expected to influence the nucleation and growth of the succeeding eutectoid decomposition process.

• Journal of Ginseng Research
• /
• 제36권3호
• /
• pp.322-326
• /
• 2012

Results of karyological study of intact plants and some callus lines of Panax ginseng are presented. In the native plants of P. ginseng the nucleus with 1 nucleolus (90%) dominate, and nucleus with 2 nucleoli is rare. One nucleolar nucleus also dominate in interphase nuclei of cells of cultivated P. ginseng (from 2006), but we also found nucleus with 2 to 3 nucleoli in the same cell lines. Interphase nuclei of P. ginseng in long cultivated lines (from 1988) contain 1 to 9 nucleoli, with a predominance of nuclei containing from 3 to 4 nucleoli. It was shown that long-time cells (cultivated since 1988) had cytogenetic changes such as increase level of polyploid and aneuploid cells, increase of nucleoli number into interphase nucleus and decrease of nuclei/nucleoli ratio. These long-time cultivated cells had very low ginsenoside content.