• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.3
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• pp.215-222
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• 2001

Neural network based models of semiconductor manufacturing processes have been shown to offer advantages in both accuracy and generalization over traditional methods. However, model development is often complicated by the fact that back-propagation neural networks contain several adjustable parameters whose optimal values unknown during training. These include learning rate, momentum, training tolerance, and the number of hidden layer neurOnS. This paper presents an investigation of the use of genetic algorithms (GAs) to determine the optimal neural network parameters for the modeling of plasma-enhanced chemical vapor deposition (PECVD) of silicon dioxide films. To find an optimal parameter set for the neural network PECVD models, a performance index was defined and used in the GA objective function. This index was designed to account for network prediction error as well as training error, with a higher emphasis on reducing prediction error. The results of the genetic search were compared with the results of a similar search using the simplex algorithm.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.763-767
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• 2005

Effect of ${\alpha}-amylase$ and various emulsifiers on characteristics of bread dough were examined. Fungal or bacterial ${\alpha}-amylase$ and various emulsifiers including monoglyceride (MG), sodium stearoyl-2-lactylate (SSL), and diacetyltartaric acid ester of mono- and diglycerides (DATEM) were added to bread dough both individually and as mixtures. Rheological characteristics of various bread doughs were examined through falling number, farinograph, alveograph, and rapid visco analysis. Results obtained showed falling number decreased via degradation of starch by ${\alpha}-amylase$. In farinogram, addition of ${\alpha}-amylase$ and emulsifiers in dough decreased consistency, water absorption, mechanical tolerance index, and dough development time. Farinogram characteristic was improved by adding SSL+MG to dough formula. Similar to farinogram addition of ${\alpha}-amylase$ and emulsifiers in alveogram of dough decreased overpressure, extensibility, swelling index, and deformation energy. Whereas addition of ${\alpha}-amylase$ did not affect pasting temperature, viscosity of dough tended to decrease.

• Research in Plant Disease
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• v.29 no.2
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• pp.137-144
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• 2023

Exserohilum turcicum is a fungus that causes northern corn leaf blight (NCLB) and has deleterious effects on maize production globally. Therefore, it is prudent to mitigate the effects of NCLB using genetic diversity. The objective of this research was to assess the severity of NCLB disease on the growth and yield of various maize genotypes. A randomized complete block design field experiment, replicated three times, was conducted to evaluate the effect of E. turcicum on 10 maize hybrids. Percent disease index, plant height, and leaf area were recorded at the silk stage. Cob weight, grain fresh weight, and grain yields were determined at harvest maturity. All measured parameters were significantly different (P<0.05) between the maize hybrids. Of the 10 genotypes, four (PAN 4R-528R, PAN 4R-728BR, PAN 3R-724BR, and P1788BR) were susceptible, five (DKC74-74BR, PAN 5R-582R, PAN 5R-890R, PAN 5R-854R, and PAN 5R-590R) were moderately susceptible, and one (DKC80-40BR) was moderately resistant. DKC80-40BR exhibited greater cob weight, while DKC74-74BR was superior in all other plant growth and yield components. Interestingly, although not significant (P>0.05) and high, maize growth and yield parameters had negative correlations with disease incidence, except for grain fresh weight. Therefore, DKC80-40BR may be selected for cultivation in areas prone to NCLB to reduce maize susceptibility to the disease, while DKC74-74BR may improve crop performance. These hybrids could be considered as potential sources of resistance or tolerance to NCLB for further validation by plant breeders.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.9
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• pp.1317-1324
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• 1998

In general, DI gasoline engine has the advantages of higher power output, higher thermal efficiency, higher EGR tolerance and lower emissions due to the operation characteristics of increased volumetric efficiency, compression ratio and ultra-lean combustion scheme. In order to apply the concept of stratified charge into direct injection gasoline engine, some kinds of methodologies have been adapted in various papers. In this study, a reflector was adapted around the injector nozzle to apply the concept of stratified charge combustion which leads the air-fuel mixture to be rich near spark plug. Therefore, the mixture near the spark plug is locally rich to ignite while the lean mixture is wholly introduced into the combustion chamber. The characteristics of combustion is analyzed with the variations of fuel injection pressure and load in a stratified -charge direct injection single cylinder gasoline engine. The obtained results are summarized as follows ; 1. The MBT spark timing approached to TDC with the increase of load on account of the increase of evaporation energy, but has little relation with fuel injection pressure. 2. The stratification effects are apparent with the increase of injection pressure. It is considered by the development of secondary diffusive combustion and the increase of heat release of same region, but proceed rapidly than diesel engine. Especially, in the case of high pressure injection (l70bar) and high load (3.0kgf m), the diffusive combustion parts are developed excessively and results in the decrease of peak pressure than in the case of middle load. 3. The index of engine stability, COVimep value, is drastically decreased with the increase of load. 4. To get better performance of DI gasoline engine development, staged optimizaion must be needed such as injection pressure, reflector, intake swirl, injection timing, chamber shape, ignition system and so on. In this study, the I50bar injection pressure is appeared as the optimum.

• Culinary science and hospitality research
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• v.20 no.4
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• pp.127-143
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• 2014

This study investigated color barley powder substituted for wheat flour in bread recipes with the amounts of 0%, 5%, 10%, 15% and 20%. Color barley powder consisted of 9.35% of moisture content, 9.37% of crude protein, 1.64% of crude fat and 2.96% of crude ash. Water soluble dietary fiber is 3.21, insoluble dietary fiber is 4.91, total dietary fiber content is 8.12, and ${\beta}$-glucan is 49.31. DPPH radical scavenging activity is 56.76%, total phenol content is 234.34. The farinograph measurement result of the bread made with color barley powder showed that consistency, water absorption, development time and time breakdown have decreased. The alveogram measurement result of the bread made with color barley powder showed that overpressure, extensibility, swelling index and deformation energy have increased. The amylograph measurement result of the bread made with color barley powder showed that peak viscosity, hot past viscosity and breakdown have decreased. Baking loss and specific loaf volume have decreased as the color barley powder content increased. The chromaticity measurement result showed that the 'L' and 'b' of bread have increased as the color barley powder content increased, while the chromatic 'a' value increased. The texture measurement result showed that the hardness and gumminess of bread have increased as the color barley powder content increased. cohesiveness, springiness and chewiness have decreased. Overall preference scores showed a high overall acceptability for the bread made with 10% color barley powder.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.1
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• pp.67-76
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• 2002

Objective: To assess the difference of baseline hormonal status and pathophysio logy, and confirm the risk factors for long term complication according to Body Mass Index in women with polycystic ovary syndrome. Materials and Methods: Serum level of LH, FSH, Estradiol, Prolactin, Testosterone, DHEA-S, fasting insulin were measured and 100 gm oral glucose tolerance test and endometrial biopsy were performed in total 75 chronic anovulation patients and 20 normal cycling infertility patients. 95 evaluated patients were divided into 3 groups including patients with chronic anovulation having BMI below 25, BMI beyond 25.1, normal cycling infertility patients, Group 1 (n=39), Group 2 (n=36), Group 3 (n=20), respectively. Statistical analysis was performed respect to relationship between BMI and measured hormone level, sum of glucose level during 100 gm OGTT, insulin resistance using t-test, ANOVA test, Post Hoc test, Mann-Whitney test. p<0.05 was considered as statistically significant. Results: Serum LH level and LH/FSH ratio was significantly higher in Group 1, compared than Group 2 or 3 (p<0.05), BMI and LH, LH/FSH ratio was negatively correlated (r=-0.351, r=-0.318). There was no significant difference according to BMI in FSH, testosterone, estradiol, prolactin, DHEA-S level. Fasting insulin and sum of glucose level during 100 gm OGTT were significantly higher in Group 2 compared than Group 1 or Group 3 (p<0.05), there was no significant difference between Group 1 and Group 3. Insulin resistance was more frequently identified in Group 2 compared than Group 1 (p=0.001). Conclusions: BMI and LH, LH/FSH ratio were negatively correlated, so clinical significance of LH, LH/FSH ratio in diagnosis of PCOS may be attenuated by increasing body weight. Overweight patients with chronic anovulation may be the risk group for developing insulin resistance, hyperinsulinemia, glucose intolerance, later type 2 DM. Hyperinsulinemia may operate mainly in overweight chronic anovulation patients in development of hyperandrogenism.

• Korean Journal of Ecology and Environment
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• v.50 no.4
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• pp.403-410
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• 2017

We collected fishes at the 12,873 sites in stream order (1~7) from 2008 to 2016. In the results, two populations(Zacco platypus and Zacco koreanus) represented distributional differences in the stream order gradient, and correlation analysis showed that the two populations had a potential competitive relationship. The ecological characteristics of the fish except for the Z. platypus and the Z. koreanus, according to the gradient of stream order showed a pronounced gradient in the species such as intermediate species, sensitive species, carnivores, herbivores and omnivores. The two populations showed a high correlation between intermediate species, sensitive species of the tolerance guild and omnivores, insectivores of the trophic guild. Fish assessment index (FAI) was negative relation with stream order. According to the stream order gradient, the two populations showed different correlations with FAI.

• Applied Biological Chemistry
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• v.32 no.4
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• pp.327-331
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• 1989

In this study the Theological properties between C1-treated soft wheat flour and untreated soft wheat flour was determined. Chlorine treatment lowered pH of the flour in a linear fashion. Water absorption and dough stability was high in proportion to the increase of treatment level but mechanical tolerance index was reduced by each increment of chlorine. The valorimeter value did not exhibit reproducible trend on treatment of chlorine. In general, resistance(BU), resistance to extension and maximum viscosity(BU) were highest in control group; lowest in 1 oz./cwt. flour and tended to rise in 2 oz./cwt. flour when it fermented in chamber for 90 min and 135 min. The maximum viscosity was highest (1,160BU) in 4 oz./cwt. flour and temperature at maximum viscosity tended to rise gradually in proportion to the increase of treated level.

• Progress in Medical Physics
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• v.25 no.1
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• pp.23-30
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• 2014

The purpose of this study is to evaluate the developed dose verification program for in vivo dosimetry based on transit dose in radiotherapy. Five intensity modulated radiotherapy (IMRT) plans of lung cancer patients were used in the irradiation of a homogeneous solid water phantom and anthropomorphic phantom. Transit dose distribution was measured using electronic portal imaging device (EPID) and used for the calculation of in vivo dose in patient. The average passing rate compared with treatment planning system based on a gamma index with a 3% dose and a 3 mm distance-to-dose agreement tolerance limit was 95% for the in vivo dose with the homogeneous phantom, but was reduced to 81.8% for the in vivo dose with the anthropomorphic phantom. This feasibility study suggested that transit dose-based in vivo dosimetry can provide information about the actual dose delivery to patients in the treatment room.

• Advances in Traditional Medicine
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• v.3 no.4
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• pp.196-204
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• 2003

Aqueous extract of Enicostemma littorale is reported to have antidiabetic activity. In the present investigation, we studied the effect of aqueous extract of E. littorale and its different fractions i.e., toluene, chloroform, ethyl acetate, n-butanol fractions and remaining residual fraction in streptozotocin (STZ)-induced neonatal type 2 diabetic rats. Fasting glucose and insulin levels in NIDDM were significantly (P<0.05) higher than control rats and they were significantly decreased by treatment with aqueous extract of E. littorale and its n-butanol and ethyl acetate fractions. Results of oral glucose tolerance test (OGTT) showed that aqueous extract and its n-butanol and ethyl acetate fractions significantly (P<0.05) decrease both $AUC_{glucose}$ and $AUC_{insulin}$ values in NIDDM treated groups. Insulin sensitivity $(K_{ITT})$ index of NIDDM control was significantly lower as compared to normal control and this was significantly (P<0.05) increased after treatment with aqueous extract, its n-butanol and ethyl acetate fractions. Treatment with aqueous extract of E. littorale and its n-butanol and ethyl acetate fractions lowered the elevated cholesterol and triglyceride levels observed in NIDDM rats. Treatment with aqueous extract of E. littorale and its n-butanol fraction showed significant decrease in creatinine, urea, SGPT and SGOT levels as compared to NIDDM control rats. However ethyl acetate fraction showed significant changes only in creatinine and SGOT levels, and not in the levels of urea, and SGPT as compared to NIDDM control rats. Treatment with toluene, chloroform and residual fractions of E. littorale did not produce any effect on glucose, insulin, triglyceride, cholesterol, creatinine, urea, SGPT or SGOT levels as compared to NIDDM control rats. Our data suggest that n-butanol and ethyl acetate fractions contain the active compounds which may be responsible for the above activity and associated complications in NIDDM diabetes mellitus.