• 한국음향학회지
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• 제39권1호
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• pp.57-63
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• 2020

바이노럴 비트는 양이에 도달한 소리의 주파수 차이로 유발된 주관적인 맥놀이 현상이다. 물리적으로 맥놀이의 세기는 주파수가 다른 두 신호의 크기에 영향을 받는다. 따라서 바이노럴 비트는 좌우 청력의 차이에 따라 영향을 받을 것으로 예상된다. 본 연구에서는 청력에 따른 효과를 평가하기 위해, 정상 청력을 가진 34명의 피실험자가 한 쪽 귀에 기준음[440 Hz, 50 dB Sound Pressure Level(SPL)], 반대 측 귀에 주파수가 다른 제시음(450 Hz)을 SPL을 감소하며 들을 때, 주관적으로 느끼는 바이노럴 비트 의 세기의 변화를 Semantic Differential Method(SDM) 이용하여 평가하도록 했다. 실험 결과 피실험자가 느끼는 바이노럴 비트의 세기는, 좌우 소리의 SPL 차이가 역치(2.2 dB)보다 크면, 좌우 소리의 SPL 차이가 증가함에 따라 지속적으로 유의하게 감소하는 것으로 나타났다. 이러한 결과는 바이노럴 비트 효과를 최대로 하기 위해 좌우 청력 차이를 적절한 범위(예. 2.2 dB) 이내로 유지하는 것이 필요하다는 것을 시사한다.

• 동의생리병리학회지
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• 제16권2호
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• pp.353-358
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• 2002

To test the protective effect of herbal medicine against oxygen free radical-induced myocardiotoxicity, cytotoxicity of xanthine oxidase/hypoxanthine (XO/HX) was examined using MTT, TBARS, and beating rate assay in the presence of water extract of Sujeom-san(SJS) or single consituents of its prescription. Myocardial toxicity was evaluated in neonatal rat myocardiocytes in cultures. In the present paper, XO/HX resulted in a decrease in viability and beating rate and increases in lipid peroxidation in cultured myocardial cells. In the effect of SJS water extract, it showed effects from the cardiocytotoxicity induced by XO/HX treatment such as increases in beating rate and decreases in lipid peroxidation. In the effect of Rhizoma Corydalis (RC), Faeces Trogopterori (FT), Fructus Amomi Tsaoko (FAT) and Myrrha on the cardiocytotoxicity, they were significantly effective in blocking the XO/HX-induced cardiocytotoxicity by increase of beating rate in FAT and FT group as well as decrease of lipid peroxidation in FT and RC group. These results show that oxygen free radical elicits toxic effects in cultured myocardial cells derived from neonatal rat, and suggest that water extract of Sujeomsan, Rhizoma Corydalis, Faeces Trogopterori, Fructus Amomi Tsaoko or Myrrha is very effective in the prevention of xanthine oxidase/hypoxanthine- induced cardiotoxicity.

• 한국식생활문화학회지
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• 제7권4호
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• pp.291-296
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• 1992

본 연구에서는 전통적 강정 제조법을 표준화하기 위하여 주재료인 찹쌀의 수침기간과 익힌 찹쌀 반죽의 교반시간에 대한 최적수준을 결정하였다. 찹쌀의 흡수율은 수침 2시간 후에 거의 최고치에 달하였으며, 그 이후에는 거의 일정한 경향을 보였다. 수침 7일의 수침액은 가장 낮은 pH를 나타내었고 찹쌀 수침액의 환원당량은 수침기간이 길어짐에 따라 증가하였다. 강정의 팽화율은 수침 5일에서 가장 높았으며 교반횟수가 증가함에 따라 감소하는 경향이었다. 반응표면방법을 이용하여 관능검사 결과로부터 처리요인의 최적수준을 다음과 같이 결정하였다 : 강정 제조시 찹쌀의 최적 수침시간은 7일, 익힌 찹쌀 반죽의 최적 교반시간은 4분(40회/분).

• 동의생리병리학회지
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• 제30권1호
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• pp.40-46
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• 2016

Many medicinal plants have been used for the treatment of edema, jaundice, and gonorrhea in traditional Oriental medicine. This screening study was designed to search the positive inotropic effects of herbal extracts in beating rabbit atria. Aquarius extracts of twenty six herbs were examined in atrial mechanical dynamics such as pulse pressure and stroke volume and atrial natriuretic peptide (ANP), one of the main hormones involved in the regulation of the body fluid and blood pressure homeostasis in perfused beating rabbit atria. Sophora flavescens Ait., Rheum officinale Baill., Acorus gramineus Sol., Chelidonium majus L., Pulsatilla koreana Nakai., Reynoutria japonica Houtt., Euphorbia lathyris L., Pyrrosia lingua (Thunb.) Farwell, Poncirus trifoliata Rafin., Anemarrhena asphodeloides Bunge, Kochia scoparia Schrad. significantly increased stroke volume and pulse pressure. However, those herbal extracts were not induced ANP secretion. We clarified the eleven herbal extracts for the positive inotropic effect independent of ANP secretion in beating rabbit atria. Thus these results provide a beneficial data for the treatment of the impairment of body fluid and blood pressure in traditional Oriental medicine.

• 펄프종이기술
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• 제47권5호
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• pp.68-73
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• 2015

Electron beam irradiation is also an eco-friendly treatment compared to other physical and chemical treatments. In this study, we attempted to evaluate the possibilities of energy savings by applying electron beam irradiation to the refining process. After softwood unbleached kraft pulp (UKP) was irradiated with electron beams at 50 and 100 kGy, it was beaten in a laboratory beater, and then its freeness and fiber properties were analyzed. The physical properties of their fiber handsheet were also and measured. As the irradiation dose of the electron beam and the beating time increased, lower freeness and fiber lengths of the UKP were observed. Handsheets made from UKP that was irradiated by electron beam and beaten showed a reciprocal relationship with the irradiation dose of the electron beam, in particular, the strength of the handsheets decreased dramatically at 100 kGy of irradiation. Therefore, it was confirmed that electron beam irradiation is effective in reducing the beating time or beating energy. But the irradiation dose must be controlled under 50 kGy to minimize the loss of paper strength.

• 한국지진공학회논문집
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• 제3권2호
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• pp.67-76
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• 1999

이동하중에 의한 교량의 공진현상은 차량의 속도와 유효타격간격에 의해 결정되는 이동하중의 운행진동수와 교량의 고유진동수가 일치할 경우 발생하게 된다. 철도교의 경우에는 정해진 열차만 통행하게 되므로 이러한 유효타격간격이 정량적으로 정해져있다 본 연구에서는 고속전철하중을 받는 교량의 지간장 변화에 따른 교량의 공진현상과 공진소멸현상을 분석하고자 한다. 강합성형 철도교에 대하여 판요소와 공간뼈대요소의 조합에 의한 3차원 모델링을 적용하였으며 또한 고속전철하중은 이동집중하중 모델과 3차원 모델링 두가지 방법을 사용하였다 수치예제로서 지간장 변화에 따른 수직처짐의 동적확대계수 상판의 최대수직가속도 단부회전각 등의 동적응답 분석을 통하여 고속철도 교량의 동적안정성에 적합한 지간장 설계기준에 대하여 논의 하였다.

• Archives of Pharmacal Research
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• 제28권8호
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• pp.930-935
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• 2005

We have investigated the effects of relatively high concentration of carbachol (CCh), an agonist of muscarinic acetylcholine receptor (mAChR), on cardiac automaticity in mouse heart. Action potentials from automatically beating right atria of mice were measured with conventional microelectrodes. When atria were treated with $100{\mu}M$ CCh, atrial beating was immediately arrested and diastolic membrane potential (DMP) was depolarized. After exposure of the atria to CCh for $\~4 min$, action potentials were regenerated. The regenerated action potentials had lower frequency and shorter duration when compared with the control. When atria were pre-exposed to pirenzepine $(1{\mu}M)$, an $M_1$ mAChR antagonist, there was complete inhibition of CCh-induced depolarization of DMP and regeneration of action potentials. Pre-exposure to AFDX-116 (11 ({2-[(diethylamino)-methyl]-1-piperidyl}acetyl)-5, 11-dihydro-6H-pyridol[2,3-b][1,4] benzodiazepine-6-one base, $1{\mu}M$), an $M_2$ mAChR antagonist, failed to block CCh-induced arrest of the beating. However, prolonged exposure to CCh elicited gradual depolarization of DMP and slight acceleration in beating rate. Our data indicate that high concentration of CCh depolarizes membrane potential and recovers right atrial automaticity via $M_1$ mAChR, providing functional evidence for the role of $M_1$ mAChR in the atrial myocytes.

• 동의생리병리학회지
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• 제17권4호
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• pp.1031-1036
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• 2003

To certify the protective effect of herbal medicine against oxygen free radical-induced myocardiotoxicity, cytotoxicity was measured using TBARS assay and Beating rate in the presence of Tongryeong-san(TRS) extracts or single constituents of this prescription. Myocardial toxicity was evaluated in neonatal rat myocardiocytes in cultures. In the present study, xanthine oxidase/hypoxanthine (XO/HX) resulted in a increase in lipid peroxidation and decreases in beating rate in cultured myocardial cells. In the effect of TRS extract, it showed the prevention from the XO/HX-induced cardiotoxicity by the increases of beating rate as well as the decrease of lipid peroxidation, In the protective effect of Faeces Trogopterori(FT), Pollen Typhae(PT), Caulis Akebiae(CA) and Radix Paeoniae Rubra(PRR), all the extracts were significantly effective in the protection of XO/HX-induced cardiotoxocity in cultured myocardial cells by the increase of beating rate as well as th decrease of lipid peroxidation. From these results, they show that XO/HX is cardiotoxic in cultured myocardial cells derived from neonatal rat, and it suggests that TRS, FT, PT, CA and PRR extracts are positively effective in the blocking in XO/HX-induced cardiotoxicity.

• 펄프종이기술
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• 제34권4호
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• pp.22-29
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• 2002

This research was conducted to investigate the morphological characteristics of fine fibers produced during beating process of high yield pulp treated with ozone and the distribution of lignin in the produced fine fibers. Thermomechanical(TMP) pulp and chemithermomechanical(CTMP) pulp of spruce and CTMP of white birch were beaten to reach 200$m\ell$ CSF, and then the fine fibers were observed using ultraviolet microscope. The fine fibers produced from TMP and CTMP of spruce using treated with ozone for 15 minutes were fragments of fiber surfaces or cell corners, and most of them contained lignin. However, lignin was not observed in the fibers after 15 minutes of ozone treatment. The fine fibers produced from CTMP of white birch were broken pieces or fragments of fiber surfaces or cell corners. The lignin was observed in the fibers until 5min of ozone treatment but no lignin was observed after 5 minutes of ozone treatment. Different morphological characteristics of TMP and CTMP explained both the different morphological characteristics and the distribution of lignin observed in the fine fibers produced from the beating process of TMP and CTMP treated with ozone.

• 한국광학회지
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• 제6권4호
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• pp.324-330
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• 1995

단일모드광섬유에서의 유도브릴루앙산란을 설명하고 광원에 의한 기준신호 및 광섬유에서의 유도브릴루앙산란 신호를 이용해 헤테로다인 방식으로 주파수변화를 조사하였다. 수개의 종모드를 갖는 광원과 고리형 광섬유공진기를 결합하여 간단하게 스팩트럼분석기로 광섬유에서의 브릴루앙산란을 관측할 수 있다. 이 방법은 기준맥놀이 신호를 사용하기 때문에 13GHz 영역에서의 주파수변화를 수 GHz의 낮은 영역에서의 주파수변화로 브릴루앙산란 신호를 볼 수 있다. 분산천이광섬유와 크래딩에 Ti 도핑된 광섬유및 일반단일모드광섬유를 적절히 선택하여 13GHz 영역에서의 주파수변화를 수 GHz 이하의 영역에서 주파수변화로 조사하니 각각 3.32GHz, 900MHz 및 870MHz였다.