• Archives of Pharmacal Research
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• 제19권3호
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• pp.183-190
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• 1996

There are a wide variety of semi-solid ointments used for healing the skin diseases, whose therapeutic and skin penetration abililties may greatly differ from one another depending on the compositions of ointment vehicles. A computer optimization technique was applied to obtain the optimum formula of o/w type ointment giving the in vitro maximum absorption rate through hairless rat skin membrane. Some of the formulations were selected to find out a relationship between skin penetration of ointment and its Theological characteristics. The experimental value of absorption rate obtained from the ointment by optimum formula agreed well with the theoretical value obtained from a polynomial regression analysis, Three kinds of ointments selected among 15 formulations were obtained with a concentric cylinder type rheometer (Model; Rheolab SM-HM Physica, Germany) at 20, 30, 40 and $50^{\circ}C$ for rheograms of rhelolgical properties of o/w type ointments. As the temperature was raised, all products showed a decrease in both shear stress and yield values. The higher skin penetration, the lower shear stress showed.

• Elastomers and Composites
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• 제45권1호
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• pp.44-50
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• 2010

기계적 혼련법으로 butadiene rubber(BR)과 대표적인 결정성고무인 chloroprene rubber(CR) 블렌드 혼련물을 제조하여, 이들의 가교 거동, 기계적 성질, 내오존성 및 동적 기계적 성질 등을 검토하였다. 내오존시험에 있어서 50 wt% CR 고무의 첨가에 의하여 크게 개선됨을 확인할 수 있었다. Rheovibron에 의한 동적 계적 특성 측정의 결과로부터 BR/CR 블렌드는 두 개의 전이를 보였으며 $tan{\delta}$ 피이크의 위치는 CR 고무의 함량이 증가함에 따라 고온 쪽으로 이동함을 확인할 수 있었다. 한편 CR 고무량이 증가할수록 최적 가황시간이 증가하는 경향을 보였다.

• 한국가구학회지
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• 제14권2호
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• pp.1-12
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• 2003

This study was carried out to determine the mechanical and physical properties of particle boards glued with condensed tannin (Wattle Tannin) powder that was single-molecule phenolic compounds like powdered phenolic resin. Our findings are; 1) It is necessary to spray water on the chip surfaces for effective application of powdered -form tannin resin. It shows that the best and optimum mat moisture increase is 14% of water spray on the surface of chips for developing PB properties. 2) In general, for both liquid and powdered tannin adhesives, their physical and mechanical properties has been proportional to the increase of resin level. But, the most efficient addition ratio is 16% of resin on dry basis. Specially, it is found that the resin level influences on the amount of free formaldehyde emission. The higher the resin level is, the lower the emission is. These phenomena seem to result from the increase of hexamine or formaline in the adhesives used as a hardener, that reduce the free-formaldehyde amount by reaction of tannin of poly-molecule and water. 3) The optimum condition for manufacturing PBs is the condition of hexamine of 5% and formaline of 6% in mechanical and physical properties. Hexamine is superior to formaline in mechanical and physical properties along with the control of the free formaldehyde emission amount. The result of NaOH's addition is insignificant in all experiments of both mechanical and physical properties.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.1047-1053
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• 2009

This paper examined an applicability of optimum algorithm to develope an electric railway pole foundation automated design system. Based on the optimization theory that considered subgrade and bearing capacity characteristics, decided an optimum section of electric railway pole foundation. In this research, Optimum algorithm used the feasible direction method in structural analysis and design efficiently. Design variables are considered geometric properties and anchor bolt area of the electric railway pole foundation as optimum construction cost. Constraints are considered settlement., overturning and activity of foundation. And, also composed flexural and shearing strength. According to optimum analysis result., optimization theory is available more economical design comparing with railway pole foundation that is constructed by current standard drawing, and applicability verified in automated design system development.

• 펄프종이기술
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• 제40권1호
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• pp.41-46
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• 2008

In this study, dewaterability, one of the important properties of wastewater sludge, was investigated using a simple capillary suction time (CST) measurement method. It turned out that one could use the results of CST to find optimum flocculants ratio to improve drainage in wastewater treatment for the printing paper, tissue paper, and newsprint paper mill. Since the optimum ratio of flocculants could be determined with the value of CST, COD removal efficiency could be improved and optimum floc strength could be achieved with precise ratio of flocculants. It was thus that using CST for determining the optimum ratio of flocculants could be economical by reducing the amount of flocculants. Dewaterability could be measured within several seconds using the values of CST in a precise way. The dewaterability could also be useful in investigating the optimum ratio of flocculants.

• 한국농공학회지
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• 제11권4호
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• pp.1783-1790
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• 1969

It is one of the most economical method of soil stabilization works to compact soil, which increases soil density artificially. Compaction effort is to lessen void of soils, and consequently its aim is to enlarge friction and cohesion force, and reduce permeability of soil. Factors in compaction effort are moisture content, grain size, grain size distribution, physical properties, compaction method and temperature of soils etc. The results obtained in this study on the effects that grain size, gradation and physical properties influence upon compaction effort for 20 samples under the constant compaction method, are summarized as follows: 1. The bigger the maximum dry density is, the smaller the optimum moisture content is, on the other hand, the smaller the maximum dry densityis, the bigger the optimum moisture content is, ingeneral. 2. The coarser the grain size is, the bigger the maximum dry density is, and the optimum moisture content becomes small, and dry density-moisture content curve has the sharp peak, generally. Also, the finer the grain size is the smaller the maximum dry density is, and the optimum moisture content shows the big value, and dry density-moisture content curve has the dull peak. 3. The maximum dry density shows the biggest value on the sample to be about 15% of particles finer than No. 200 sieve. The more the percent passing of No. 10 sieve increase, the smaller the maximum dry density is. Soils which have uniformity coefficient less than 5 in particles larger than 0.074mm hardly show dry density-moisture content curve. 4. There is a relation which is ramax＝2.3948-0.0376 Wopt between the maximum dry density and the optimum moisture content, namely, the maximum dry density is increased in proportion to decrease of the optimum moisture content. 5. There are relations to be the straight lines which the maximum dry density decrease, on the other hand, the optimum moisture content increase in accordance with enlargement of Atterberg Limit(LL, PL, PL) in compacted soils.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.414-419
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• 2001

In this research, reliability based optimum design is presented for the thin walled beam structures. Deterministic and stochastic optimum design are compared for the thin walled beam structures. Monte Carlo simulation is used for stochastic optimum design with consideration of probabilistic distribution of representative section properties of the thin walled beams with the Response Surface Method.

• 한국연초학회지
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• 제11권1호
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• pp.79-85
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• 1989

For the Purpose of this study, were researched the optimum condition preconditioning condition of orient tobacco leaves . The loss of 3-methyl pentanoic acid (3-MP) component of BASMA leaves in the treatment process amount to about 60% , but the loss of 3-MP At the optimum conditions of BASMA CTC treatment, the temperature was 45-$65^{\circ}C$ and the treatment time 25-35 minutes. And further, the physical properties of BASMA after CTC treatment was remarkably similar to the control's. Since VTC minimized the loss, it is suggested that CTC method should be changed by VTC method.

• BMB Reports
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• 제39권4호
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• pp.426-431
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• 2006

Embryonic stem cells (ESCs), representing a population of undifferentiated pluripotent cells with both self-renewal and multilineage differentiation characteristics, are capable of spontaneous differentiation into cardiomyocytes. The present study sought to define the kinetic characterization of lactate dehydrogenase (LDH) and creatine kinase (CK) of ESC- and neonatal-derived cardiomyocytes. Spontaneously differentiated cardiomyocytes from embryoid bodies (EBs) derived from mouse ESC line (Royan B1) and neonatal cardiomyocytes were dispersed in a buffer solution. Enzymes were extracted by sonication and centrifugation for kinetic evaluation of LDH and CK with spectrophotometric methods. While a comparison between the kinetic properties of the LDH and CK of both groups revealed not only different Michaelis constants and optimum temperatures for LDH but also different Michaelis constants and optimum pH for CK, the pH profile of LDH and optimum temperature of CK were similar. In defining some kinetic properties of cardiac metabolic enzymes of ESC-derived cardiomyocytes, our results are expected to further facilitate the use of ESCs as an experimental model.

• 한국식품영양과학회지
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• 제27권1호
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• pp.80-86
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• 1998

This work was designed to determine the optimum roasting conditions with application of a pressure roaster for improving the roasting process of the Polygonatum sibiricum tea which has been roasting with a traditional method. Soluble solid content of the Polygonatum cibiricum tea was 63.16% in the tea roasted at 0.85kgf/$\textrm{cm}^2$(roasting pressure) and 13.9min(roasting time) which were maximum point by the ridge analysis. The optimum conditions predicted for each corresponding sensory properties of the Polygonatum cibirium tea were 0.87kgf/$\textrm{cm}^2$ and 9.2min in color, 0.89kgf/$\textrm{cm}^2$ and 9.7min in sweet 0.72kgf/$\textrm{cm}^2$ and 5.4min in burnt flavor, 0.89kgf/$\textrm{cm}^2$ and 9.9min in appetizing flavor, 0.87kgf/$\textrm{cm}^2$ and 9.3min in aftertaste, 0.89kgf/$\textrm{cm}^2$ and 10.0min in aroma, and 0.88kgf/$\textrm{cm}^2$ and 9.6min in overall acceptability of the tea. The optimum conditions based on the soluble solid content and sensory properties of the Polygonatum cibiricum tea, were 0.83~0.88kgf/$\textrm{cm}^2$ and 9.7~10.4min.