• 제어로봇시스템학회논문지
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• 제11권8호
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• pp.656-661
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• 2005

This paper is concerned with an iterative linear matrix inequality (LMI) approach to the design of a structurally constrained output feedback controller such as decentralized control. The structured synthesis is formulated as a novel rank-constrained LMI optimization problem, where the controller parameters are explicitly described so as to impose structural constraints on the parameter matrices. An iterative penalty method is applied to solve the rank-constrained LMI problem. Numerical experiments are performed to illustrate the effectiveness of the proposed method.

• 소음진동
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• 제6권1호
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• pp.57-64
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• 1996

The objectiv of this paper is to offer the method of the optimum structural modification by fixing the stiffener on the structure. The vibrational characteristics of a open box type structure are analyzed by the sub-structure synthesis method and sensitivies of each sub-structure are calculated by sensitivity analysis method. The positions to modify are found and the quantities to change are obtained by optimization techniques. As the result, it was found that; (1) The sensitivites of the natural frequency could easily be calculated by the sensitivity analysis method and the optimum position to fix stiffeners could be found. (2) The exact size of stiffeners could be calculated by the optimum structural modification method and the natural frequency could be easily shifted to the objective value. (3) It could be confirmed that the stiffener is a effective tool for accomplishing structural modification.

• Structural Engineering and Mechanics
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• 제44권3호
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• pp.305-323
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• 2012

Structural defects such as cracks are the source of local flexibilities and cause deficiencies in structural resistance. In the engineering constructions, structural elements sometimes are subjected to axial loading. Therefore, besides crack ratios and locations, influence of applied load on the stability and dynamical characteristics should also be explored. This study offers a numerical technique for the vibration and stability analysis of axially loaded cracked beams. The model merges finite element and component mode synthesis methods. Initially, stability analysis is completed and then dynamical characteristics of beams are found. Very good conformities between outcomes of the current study and those in literature, give the confidence that proposed method is reliable and effective.

• 한국정보처리학회논문지
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• 제5권11호
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• pp.2973-2979
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• 1998

본 논문은 상위 수준 합성식의 자원 제약 조건하에서 파이프라인 데이타패스 합성을 위한 스케쥴링 알고리즘으로, 제안된 휴리스틱 알고리즘은 자원의 충돌수에 근거한 우선순위 함수를 사용한다. 자원 제약하에서 파이프라인 데이타패스 합성수를 정의하여 스케쥴링 한다. 제안 알고리즘은 실질적인 하드웨어 설계를 위해 체이닝, 멀티사이클링, 구조적 파이프라인이 지원되도록 한다. 제안 알고리즘에 의한 16 포인트 FIR 필터와 5차 엘립틱 웨이브 필터 합성 결과에 의해 다른 시스템들과의 성능을 비교하였으며, 대부분의 경우에 최적의 해를 찾을 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제9권6호
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• pp.655-665
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• 1996

The effects of feeding rice bran and beet pulp mixtures on the site and extent of digestion and microbial synthesis in fattening steers were studied. Three Holstein steers fitted with ruminal, duodenal and ileal cannulas were fed four diets in a $4{\times}3$ Youden square design. The four diets consisted of 15% Italian ryegrass hay and 85% concentrate as a control diet which included 72% rolled barley, 20% rice bran plus 40% beet pulp, 30% rice bran plus 30% beet pulp or 40% rice bran plus 20% beet pulp. All diets provided 1.8 times digestible energy required for maintenance. The digestibility of fat in the small intestine (% of flow) showed an increase with rice bran content among the by-product diets. Digestibility of structural carbohydrate both in the rumen and the whole digestive tract decreased linearly with rice bran content. The digestibility of nonstructural carbohydrate was not affected by rice bran content, but that of nonstructural, nonstarch polysaccharides was higher in the rumen and lower in the large intestine for the by-product diets than for the control diet. A rice bran content of more than 30% in the by-product diets severely inhibits ruminal microbial synthesis and digestible energy intake in fattening steers.

• 한국재료학회지
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• 제27권8호
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• pp.445-450
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• 2017

YSZ (Yttria-stabilized zirconia) is a ceramic material that is used for electronic and structural materials due to its excellent mechanical properties and specific electrical characteristics according to the Yttrium addition. Hydrothermal synthesis has several advantages such as fine particle size, uniform crystalline phase, fast reaction time, low process temperature and good dispersion condition. In order to synthesize YSZ nanoparticles with high crystallinity, hydrothermal synthesis was performed at various concentrations of NaOH. The hydrothermal process was held at a low temperature ($100^{\circ}C$), with a short process time (2,4,8 hours); the acidity or alkalinity of solution was controlled in a range of pH 2~12 by addition of NaOH. The optimum condition was found to be pH 12, at which high solubility levels of Y(OH) and Zr(OH) were reported. The synthesized nano powder showed high crystallinity and homogenous composition, and uniform particle size of about 10 nm.

• 치과방사선
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• 제17권1호
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• pp.27-49
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• 1987

Using ³H-proline as a radioactive tracer, the relationship between the ultrastructural differentiation and the site of protein synthesis has been investigated in developing red blood corpuscles. The general ultra-structure of erythropoietic cells in differentiation after 60 minutes of in vitro labeling has confirmed the results from previous investigations by Bessis, M., Thiery, J. and others. In dividing nuclei more than two-thirds of the labeling were present at the interface between heterochromatin and euchromatin. In less differentiated cells most of the grains in interphase cells was localized over the nucleus. As the cells continued to develope beyond a stage where cytoplasmic density was clearly increased over other cell lines in bone marrow, the majority of grains localized over the cytoplasmic area was decreased in more mature cells, as judged by the density of cytoplasm, and the structural changes in mitochondria, Golgi complex and polysomal configurations. These results show; 1) that the cytoplasm of erythroblast series does not change under in vitro conditions employed in the study; 2) that protein synthesis in the nucleus occurs largely at the interface between euchromatin and heterochromatin in active nuclei; and 3) that cytoplasmic synthesis of proteins continues to take place well into the normoblast stage solong as the physically visible polysomes are present in maturing red blood corpuscles.

• Journal of Microbiology and Biotechnology
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• 제7권6호
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• pp.391-396
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• 1997

Two series of carbon sources, linear primary $C_1$~$C_9$ alcohols and linear $C_2$~$C_{10}$ monocarboxylic acids were tested for PHA synthesis in Paracoccus denitrificans. The results showed that the growth-associated synthesis of PHA could be referred only to the carbon sources with odd number of carbon except methanol. For all carbon sources with even number of carbon, nitrogen limitation was required to induce PHA synthesis in P. denitrificans. Poly(3-hydroxyvalerate)[P(3HV)] homopolymer was synthesized from $C_5$, $C_7$, and $C_9$ while growing in the presence of nitrogen, but the nitrogen depletion in the later growth period incorporated 3-hydroxybutyrate(3HB) unit into the polymer chain. The optimum C/N ratio for P(3HV) homopolymer production was found to be 10 when the strain was grown on 10 ml/l of valeric acid for 96 h. P. denitrificans synthesized P(3HB-co-3HV) copolymers from n-hexanoic and n-octanoic acid. The microstructural characterics of the P(3HB-co-3HV) copolymer from n-propanol was investigated using $^13C$-nuclear magnetic resonance spectroscopy, showing a structural heterogeneity.

• 한국세라믹학회지
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• 제31권10호
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• pp.1159-1168
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• 1994

We powders were synthesized from W powders in differnet particle sizes by Self-propagating High-temperature Synthesis process (SHS) using a chemical furnace. The effects of the mole ratio of chemical fuel content, pellet thickness and the mole ratio between carbon and tungsten (C/W Ratio) on synthesis were investigated with the tungsten powders have different particle size each other. Compositional and structural characterization of these powders was carried out by scanning electron microscope (SEM0 and x-ray diffractometer. Powder characterization was carried out by the measurement of particle size distribution with laser-particle size analyzer. The amounts of WC obtained by SHS process depend very much on the particle size of tungsten powder and heat contents given in a product, i.e. as the particle size of W powder is smaller, the amounts of WC produced increase. Also the more heat contents is given, the more amounts of WC increase. By optimizing the synthesis conditions, it is possible to fabricate WC powders which have little secondary phases (W2C, C).

• KSBB Journal
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• 제8권4호
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• pp.320-327
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• 1993

스티렌/아크렬 라텍스 폴리머를 폴리에릴렌이민으 로 표면처 리하여 얻은 PEI-microspheres는 그 표면 화학적 특성이 효소의 고정화에 적합하여 배당체의 합성반응에 서 필요로 하는 alginate-enclosed micro­s spheres biocatalyst를 제조할 수 있었고 라텍스 폴리머 표변에 형성된 폴리에틸렌이민 피막은 효소 부근에 친수성 분위기를 유지하여 높은 효소활성을 나 타내었을 뿐만 아니라, 생성된 배당체가 효소에 접 근하여 가수분해되는 반응을 억제하여 배당체의 수 율과 농도를 크게 증가시 켰으므로 alginate-en closed microspheres에 의한 배당체의 합성반응이 연속생산공정으로 연구개발 될 수 있다.