• Structural Engineering and Mechanics
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• 제10권3호
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• pp.227-243
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• 2000

In a companion paper, tests on bolted side plated beams have shown that side plates can substantially increase the strength of existing reinforced concrete beams with little if any loss of ductility and, furthermore, induce a gradual mode of failure after commencement of concrete crushing. However, it was also shown that transverse interaction between the side plates and the reinforced concrete beam, that is vertical slip and which is a concept unique to side plated beams, is detrimental. Transverse interaction increases the forces on the bolt shear connectors and, hence, weakens the beam. It also reduces the ability of the composite plated beam to yield and, hence, to attain its full flexural capacity. The generic concept of transverse interaction will be described in this paper and the results used to develop a new form of rigid plastic analysis for bolted side plated beams which is illustrated with an application.

• 한국지능시스템학회논문지
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• 제14권5호
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• pp.598-603
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• 2004

광디스크에 저장된 데이터를 읽기 위한 광디스크 드라이브는 광학헤드 구동기의 포커싱 서보계와 트랙킹 서보계로 구성된다. 기존에 사용하는 지상-진상-진상 보상기는 시스템의 배속이 증가하면서 광학헤드의 구동기 제어가 점점 어려워지는 추세이다. 따라서 본 논문에서는 광학헤드 구동기 서보계 구현을 위하여 유전알고리즘 기반 퍼지 PID 제어 광학헤드 구동기 설계 기법을 제안한다. 제안된 광학헤드 구동기는 두개의 퍼지 PI, PD 제어 블록으로 구성되며 두 제어기의 퍼지 규칙은 유전알고리즘을 사용하여 최적화된다. 구동기의 포커싱, 트랙킹 서보계의 플랜트 모델은 유사하므로 트랙킹 서보계의 모의 실험만을 통하여 제안된 기법의 우수성을 보인다.

• KSBB Journal
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• 제10권2호
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• pp.137-142
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• 1995

Sucrose를 탄소원으로 이용할 수 있는 대장균 W 를 A. eutrophus PHA 합성 유전자가 cloning된 높 은 복제수의 plasmid pSYL105로 형질전환하여 단 순배지에서 배양시 $0.21g/\ell$ 의 낮은 PHB 농도를 얻었다. 이에 107}지의 복합질소원을 소량 첨가하여 PHB 합성에 미치는 영향을 살펴 보았다. Tryptone, casamino acids, casein hydrolysate, 혹은 soy bean hydrolysate의 첨가시 PHB 합성 이 10배 이 상 증대되었다. 또한 이때 sucrose로부터의 PHB 수율도 10배 이상 증가하여 이 네 가지 복합질소원 을 척정 농도로 첨가함으로써 sucrose로부터 효과적인 PHB 생산이 가능함을 알았다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.287-292
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• 2005

The crude polysaccharides(C-CPF, C-CPM, C-CPB) derived from fruiting body, mycelia and mycelia free broth of cordyceps militaris were obtained by ethanol precipitation of hot water extracts. After a batch fermentation of C. militaris was carried out in a 5 L jar vessel, endo-polysaccharide and exo-polysaccharide were obtained. They were demonstrated as the hetero polysaccharides which were composed of glucsose, galactose and mannose by performed with HPAEC(high pH anion exchange chromatography) and conformation of random coil by its complex forming ability with congo red reagent. They were purified by ion exchange (DEAE-cellulose) and gel filtration chromatography. They were monitered by phenol-sulfuric acid method and Bradford method. The NO induction activities of crude polysaccharides and purified polysaccharides derived from mycelia free broth were enhanced rather than LPS(lipo polysaccharide) which was used as a general NO inducer. These effects presumably contibute to the antitumor activities. The homogenieties and molecular weights of polysaccharides were determined by using Sepharose CL-6B. The yield, molecular weights and NO induction activities of C-CPFN Fr.III, C-CPMN Fr.III, C-CPBN Fr.II were 0.387, 0.408 and 0.153, 127 K 210 K and 36 K, 40.79%, 88.72%, and 104.17%, respectively.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제2권1호
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• pp.53-58
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• 2002

In the construction of successful fuzzy models for nonlinear systems, the identification of an optimal fuzzy model system is an important and difficult problem. Traditionally, sGA(simple genetic algorithm) has been used to identify structures and parameters of fuzzy model because it has the ability to search the optimal solution somewhat globally. But SGA optimization process may be the reason of the premature local convergence when the appearance of the superior individual at the population evolution. Therefore, in this paper we propose a new method that can yield a successful fuzzy model using VmGA(virus messy genetic algorithms). The proposed method not only can be the countermeasure of premature convergence through the local information changed in population, but also has more effective and adaptive structure with respect to using changeable length string. In order to demonstrate the superiority and generality of the fuzzy modeling using VmGA, we finally applied the proposed fuzzy modeling methodof a complex nonlinear system.

• 대한치과보철학회지
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• 제41권1호
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• pp.35-47
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• 2003

The dimensional stability of tissue conditioners characterizes the ability of the materials to yield accurate functional impressions of oral mucosa. This study evaluated the viscoelastic property and the linear dimensional changes with the factor of time and thickness of tissue conditioners ($COE-COMFORT^{TM}$, Visco-gel. $COE-SOFT^{TM}$, Soft-Liner). The thickness of these materials were changed (1.5mm, 3.0mm) and the percentage changes in dimension were measured at 1h, 12h, 24h, 36h, 3day, 7day after specimen preparation. From the results large differences appear between the various tissue conditioners. The results suggest that the period recommended for forming functional impression would be 2-3days after insertion in the mouth. in addition. it is important to select tissue conditioners suitable for functional impression because of the wide range of dimensional stability among the materials.

• BMB Reports
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• 제39권5호
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• pp.546-555
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• 2006

An acidic polysaccharide fraction that had high anti-complementary activity was isolated from the stems of Grey Mangrove in 0.15% yield. The final fractions was designated HAM-3-IIb-II. The polysaccharide fraction appeared to be homogenous by high performance size exclusion chromatography with an estimated molecular weight of 105 kDa. The isolated polysaccharide is more effective than polysaccharide K (PSK) in its anti-complementary activity at 58 ${\mu}g/ml$ of PSK and 23 ${\mu}g/ml$ of HAM-3-IIb-II that inhibit 50% of complement activity in the complement fixation assay. Structural studies indicated that HAM-3-IIb-II was rich in galacturonic acid along with arabinose, galactose and rhamnose, characterizing a pectin-type polysaccharide, which was also confirmed by FT-IR spectrum. The presence of rich neutral sugar side chains of arabinogalactans may have contributed to the expression of high activity. Traditionally, this mangrove plant is used for medicinal purposes and it appears to have some scientific applications.

• Interaction and multiscale mechanics
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• 제3권3호
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• pp.235-255
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• 2010

This paper investigates the heat equation for domains subjected to an internal source with a sharp spatial gradient. The solution is first approximated using linear finite elements, and sufficiently small time-step sizes to yield stable simulations. The main area of interest is then in the ability to approximate the solution using Generalized Finite Elements, and again explore the time-step limitations required for stable simulations. Both high order elements, as well as elements with special enrichments are used to generate solutions. When compared to linear finite elements, the high order elements deliver better accuracy at a given level of mesh refinement, but do not offer an increase in critical time-step size. When special enrichment functions are used, the solution can be approximated accurately on very coarse meshes, while yielding solutions which are both accurate and computationally efficient. The major conclusion of interest is that the significantly larger element size yields larger allowable time-step sizes while still maintaining stability of the time-stepping algorithm.

• Journal of Ginseng Research
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• 제40권2호
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• pp.121-126
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• 2016

Background: Ginsenoside F1, a pharmaceutical component of ginseng, is known to have antiaging, antioxidant, anticancer, and keratinocyte protective effects. However, the usage of ginsenoside F1 is restricted owing to the small amount found in Korean ginseng. Methods: To enhance the production of ginsenoside F1 as a 10 g unit with high specificity, yield, and purity, an enzymatic bioconversion method was developed to adopt the commercial enzyme Cellulase KN from Aspergillus niger with food grade, which has ginsenoside-transforming ability. The proposed optimum reaction conditions of Cellulase KN were pH 5.0 and $50^{\circ}C$. Results: Cellulase KN could effectively transform the ginsenosides Re and Rg1 into F1. A scaled-up biotransformation reaction was performed in a 10 L jar fermenter at pH 5.0 and $50^{\circ}C$ for 48 h with protopanaxatriol-type ginsenoside mixture (at a concentration of 10 mg/mL) from ginseng roots. Finally, 13.0 g of F1 was produced from 50 g of protopanaxatriol-type ginsenoside mixture with $91.5{\pm}1.1%$ chromatographic purity. Conclusion: The results suggest that this enzymatic method could be exploited usefully for the preparation of ginsenoside F1 to be used in cosmetic, functional food, and pharmaceutical industries.

• 산업경영시스템학회지
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• 제39권1호
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• pp.105-115
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• 2016

Ensemble classification involves combining individually trained classifiers to yield more accurate prediction, compared with individual models. Ensemble techniques are very useful for improving the generalization ability of classifiers. The random subspace ensemble technique is a simple but effective method for constructing ensemble classifiers; it involves randomly drawing some of the features from each classifier in the ensemble. The instance selection technique involves selecting critical instances while deleting and removing irrelevant and noisy instances from the original dataset. The instance selection and random subspace methods are both well known in the field of data mining and have proven to be very effective in many applications. However, few studies have focused on integrating the instance selection and random subspace methods. Therefore, this study proposed a new hybrid ensemble model that integrates instance selection and random subspace techniques using genetic algorithms (GAs) to improve the performance of a random subspace ensemble model. GAs are used to select optimal (or near optimal) instances, which are used as input data for the random subspace ensemble model. The proposed model was applied to both Kaggle credit data and corporate credit data, and the results were compared with those of other models to investigate performance in terms of classification accuracy, levels of diversity, and average classification rates of base classifiers in the ensemble. The experimental results demonstrated that the proposed model outperformed other models including the single model, the instance selection model, and the original random subspace ensemble model.