• Earthquakes and Structures
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• 제8권6호
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• pp.1463-1480
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• 2015

This research aims to develop an empirical model for simulation of time-varying frequency in earthquake ground motion so as to be used easily in engineering applications. Briefly, 10545 recordings of the Next Generation Attenuation (NGA) global database of accelerograms from shallow crustal earthquakes are selected and binned by magnitude, distance and site condition. Then the wavelet spectrum of each acceleration record is calculated by using one-dimensional continuous wavelet transform, and the frequencies corresponding to the maximum values of the wavelet spectrum at a series of sampling time, named predominant frequencies, are extracted to analyze the variation of frequency content of seismic ground motions in time. And the time-variation of the predominant frequencies of 178 magnitude-distance-site bins for different directions are obtained by calculating the mean square root of predominant frequencies within a bin. The exponential trigonometric function is then use to fit the data, which describes the predominant frequency of ground-motion as a function of time with model parameters given in tables for different magnitude, distance, site conditions and direction. Finally, a practical frequency-dependent amplitude envelope function is developed based on the time-varying frequency derived in this paper, which has clear statistical parameters and can emphasize the effect of low-frequency components on later seismic action. The results illustrate that the time-varying predominant frequency can preferably reflect the non-stationarity of the frequency content in earthquake ground motions and that empirical models given in this paper facilitates the simulation of ground motions.

• 경영과정보연구
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• 제22권
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• pp.85-115
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• 2007

Following is discovered in this study by some. First, attribute(product/non- product) of that truth that get through experiment of this study is WOM deduced result that have statistical meaning in dependent variable which is public trust only in this study. Specially, information by word of mouth type received High positive response more with non-product information by word of mouth attribute than the product attribute in all experiment products that is parted according to involvement. Consumer's response by involvement level of product can affect for site attitude, public trust, and intention to purchase by second. For example, consumer's site attitude has induced the most positive response, and can confirm positive response of High consumer most in that involvement sensitivity product in that participation reason type product and could confirm response that is the most positive in that involvement reason product even if there is for intention to purchase. Result of this study is grasped that have High mean value relatively in site attitude, product attitude, information by word of mouth effect, public trust, brand attitude, purchase intention etc. generally that product involvement and information by word of mouth attribute are interrelation by third. This can change fairly data processing process according to consumer's Involvement Level, behavior deterministic process, consumer's action with attitude formation process, and involvement for products. High occasion than is low incline more efforts in information retrieval and is discreet result such as study finding of produce.

• Journal of Pharmaceutical Investigation
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• 제31권2호
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• pp.107-112
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• 2001

In order to reduce the systemic side effects and gastrointestinal irritation after its oral adminitration, ketoprofen was formulated as water-soluble packs. The effects of fatty acids and fatty alcohols on the penetration of ketoprofen through excised rat skins were evaluated. The role of stratum corneum as a protective barrier was also investigated. Fatty acids and fatty alcohols were generally effective in promoting ketoprofen penetration. The flux of ketoprofen through rat skin was maximized when oleic acid or lauryl alcohol was used as an enhancer. As the concentration of fatty acids and fatty alcohols varied from 0% to 10%, the amounts of ketoprofen penetrated were in direct proportion to that of fatty acids but those had no relationship with that of fatty alcohols. The penetration of ketoprofen through stripped skin was enhanced compared to normal skin irrespective of enhancer type, which indicated that the action site of enhancers would be stratum corneum.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.196.1-196.1
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• 2003

Cinnamic acid derivatives(CAD) originating from vegetable kingdom have some biological activity. Effect of CAD on reversed cutaneous anaphylaxis (RCA) and hemolysin (HY) titer were studied in rats. Experiments were carried out to determine RCA as the skin edema induced at 2 hours after injection of 0.05 $m\ell$/site of anti-rat serum rabbit serum. Drugs were orally administered at one hour before antigen challenge. (omitted)

• Journal of Photoscience
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• 제9권2호
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• pp.424-426
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• 2002

Recently, much attention has been paid to the physiological functions of flavonoids associated with their antioxidant properties. However, there was a lack of information on the molecular mechanism at which flavonoids play the antioxidative role. We have already studied on the oxidation of quercetin with hydrogen peroxide and sodium hypochlorite in alcoholic aqueous solution and determined the oxidation products. Through the structural analysis of the oxidation products, it was clarified that the hydroxyl group at C-3 in the C ring plays the important role in the antioxidative action of quercetin. Successively, rutin and (+)-catechin were oxidized with sodium hypochlorite and their mono- and di-chlorinated derivatives were obtained. These facts indicate that these flavonoids can directly scavenge hypochlorous acid and the active site in this scavenging reaction is not the hydroxyl group at C-3.

• 펄프종이기술
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• 제31권1호
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• pp.23-30
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• 1999

The effects of polyelectrolytes and enzyme, alone and in combination, were investigated in OCC recycling system. Four types of the polyelectrolytes based on acrylamide, cationic and anionic monomers were applied to the enzyme-treated KOCC stock to improve the strength and drainage properties of testliner. The polyelectrolytes used in this work were designed in terms of molecular weight and charge density. The water conditions used for recycling were also varied. The results showed that the hydrolytic action of enzyme gave reduced surface area and amorphous region of fiber, and as a result, the cationic polymer was lost apparently its flocculating power due to the reduced bonding site of fiber surface. When the hardness and conductivity of water had been controlled to the conditins of OCC paper mill, the application of amphoteric polyelectrolyte to the enzyme-treated recycled stock was the most effective with respect to the strength and drainage properties of testliner.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.145-152
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• 1999

In the applying of the reinforced soil method, it would be possible to obtain reinforcement effect more than before in terms of economic if high water content clayey soils could be used as embanking material. Futhermore it would be possible to expect the expansion of the applying field of reinforced soil method too. In this study, the authors describe the analysis results on the behavior of 5 meter high walls reinforced with nonwoven geotextile having the permeability and woven geotextile or geogrid having large tensile strength on the soil ground. The behavior of the walls were investigated for about 100 days after construction and the deformations of reinforcements, lateral soil pressures, vertical and horizontal displacements of the walls were examined by automatical measuring system. It was found that this kinds of reinforcing system might effectively improve the performance of the steep walls by virtue of the reciprocal action between soil and reinforcements, and it might be concluded that construction of the clayey reinforced soil walls with three kinds of geotextiles could be done successfully even on the comparative weak ground.

• 한국안전학회지
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• 제12권4호
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• pp.102-107
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• 1997

Ground vibrations are an integral part of the process of rock blasting. The sudden acceleration of the rock by the detonation gas pressure acting on the drillhole walls induces dynamic stresses in the surrounding rock mass. This sets up a wave motion in the ground much like the motion in a bowl of jelly when disturbed by the action of a spoon. The wave motion spreads concentrically from the blasting site, particularly along the ground surface, and is therefore attenuated, since its fixed energy is spread over a greater and greater mass of material as it moves away from its origin. Some theoretical aspects of the generation and propagation of vibrations produced in rock blasting are analyzed; although it must be indicated that this is just a mere approximation to the problem, as the actual phenomena are much more complex owing to the interaction of different types of waves and their modifying mechanics.

• The Plant Pathology Journal
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• 제17권2호
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• pp.83-87
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• 2001

Disease resistance in plants is often controlled by gene-for-gene mechanism in which avirulence (avr) gene products encoding by pathogens are specifically recognized, either directly or indirectly by plant disease resistance (R) gene products. Recent studies arising from molecular cloning of a number of R genes from various plant species that confer resistance to different pathogens and corresponding avr genes from various pathogens resulted in the accumulation of a wealth of knowledge on mode of action of gene-for-gene interaction. Specially, members of the NBS-LRR class of R genes encoding proteins containing a nucleotide binding site (NBS) and carboxyl-terminal leucine-rich repeats (LRRs) confer resistance to very different types of phytopathogens, such as bacteria, fungi, oomycetes, viruses, nematodes and aphids. This article reviewed the molecular events that occur up-stream of defense response pathway, specially, bacterial avr gene protein recognition mediated by NBS-LRR type R gene product in plant based on current research results of well studied model plants.

• 한국잡초학회지
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• 제14권2호
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• pp.107-111
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• 1994

Oxyfluorfen과 chlomethoxynil의 근부처리(根部處理)에 있어서 각 식물(植物) 종간(種間)의 선택성(選擇性) 기구(機構)를 밝히기 위해 각 식물(植物)에서 약제(藥劑)의 살초작용(殺草作用)과 흡수(吸收), 이행(移行) 및 대사(代謝)등의 관계(關係)를 조사(調査)하였다. 공시식물(公試植物)은 화본과(禾本科) 식물(植物)로서 벼, 피, 수수와 옥수수를, 광엽식물(廣葉植物)로서 토마토, 양배추, 무, 오이와 메밀을 이용(利用)하였다. Oxyfluorfen은 각 식물(植物)에 대하여 chlomethoxynil보다 강한 살초(殺草) 활성(活性)을 나타내었다. Oxyfluorfen은 chlomethoxynil에 비하여 대사속도(代謝速度)가 다소 늦었지만 흡수량(吸收量)이 보다 적었기 때문에, 근부내(根部內)의 작용점(作用點)에서 Oxyfluorfen의 작용활성(作用活性)은 chlomethoxynil보다 큰 것으로 추찰(推察)되었다. Oxyfluorfen에 대하여 화본과(禾本科) 식물(植物)은 광엽식물(廣葉植物) 보다 흡수량(吸收量)이 적었다. 화본과(禾本科)인 피는 벼에 비하여 oxyfluorfen 흡수량(吸收量)의 차이(差異)는 거의 없었지만, 벼보다 큰 감수성(感受性)을 나타내었으며, 또한 광엽식물(廣葉植物)인 토마토와 오이는 메밀이나 무보다 흡수량(吸收量)이 적었음에도 불구하고 큰 감수성(感受性)을 나타내었다. 각 식물(植物)이 흡수(吸收)한 $^{14}C$-oxyfluorfen은 대부분이 대사(代謝)되지 않고 미변화(未變化)의 형태(形態)로 존재(存在)하였으며 저항성(振抗性) 식물(植物)과 감수성(感受性) 식물(植物)과의 대사율(代謝率)의 차이(差異)는 보이지 않았다. 또 water fraction을 조사(調査)한 결과, 각 식물(植物)에서 oxyfluorfen은 glucose를 포함(包含)한 식물성분(植物成分)과 소량(少量)의 포합체(抱合體)를 형성(形成)하는 것으로 나타났다. Chlomethoxynil 처리(處理)에 있어서도, 화본과(未本科) 식물(植物)은 oxyfluorfen 처리(處理)와 동양(同樣)으로 광엽식물(廣葉植物)에 비하여 약제(藥劑)의 흡수량(吸收量)이 적었다. 피는 화본과(未本科) 식물(植物)중에서 약제처리(藥劑處理) 24시간 후에 흡수율(吸收率)이 가장 낮았고, 또한, 토마토는 양배추나 메밀보다 吸收率(흡수율)이 낮았음에도 불구하고 피와 토마토만이 큰 감수성(感受性)을 보였다. 각 식물(植物)에 의해 흡수(吸收)된 $^{14}C$-chlomethoxynil의 방사능(放射能)중 60-80%는 n-hexane 중에 존재(存在)하였으며, 그 대부분은 chlomethoxynil로 부터의 것이었지만, n-hexane fraction의 TLC를 행한 결과, 벼에서 소량(少量)의 탈(脫) methyl체(體)가 대사산물(代謝産物)로서 검출(檢出)되었다. 또한, 각 식물(植物)에서 oxyfluorfen과 동양(同樣)으로 소량(少量)의 chlomethoxynil이 glucose나 다른 성분(成分)과 포합체(抱合體)를 형성(形成)하였다.