• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.1
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• pp.64-70
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• 2007

Raising exhaust gas temperature during cold-start period is very crucial to improve emission performance of SI engines because it enhances the performance of catalyst in the early stage of engine start. In this study, control variables such as ignition timing, idle speed actuator(ISA) opening and fuel injection duration were extensively investigated to analyze variations in exhaust gas temperature and engine stability during cranking period. Experimental results showed that spark timing affected engine stability and exhaust gas temperature but the effects were small. On the other hand, shortened injection duration and increased ISA opening led to a significant increase in exhaust gas temperature. Under such conditions, increase in cranking time was also observed, showing that it becomes harder to start the engine. Based on these observations, a pseudo fuel-air ratio, defined as a ratio of fuel injection time to degree of ISA opening, was introduced to analyze the experimental results. In general, decrease in pseudo fuel-air ratio raised exhaust gas temperature with the cost of stable and fast cranking. On the contrary, an optimal range of the pseudo fuel-air ratio was found to be between 0.3 to 0.5 where higher exhaust gas temperatures can be obtained without sacrificing the engine stability.

• Journal of Mushroom
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• v.16 no.4
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• pp.267-271
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• 2018

This study was carried out to select the suitable for bag cultivation of Lentinula edodes. We investigated the optimal major materials and its mixing ratio in bag cultivation of L. edodes, 'Sanjo701ho' and 'Nongjingo'. The Suitable substrates for L. edodes bag cultivation were oak sawdust and douglas fir sawdust and rice bran mixed ratio 40:40:20(v/v). At the result, the period mycelial incubation shortened up to 13~18 days compared to the control. And Yield of commercial fruiting bodies was 17~19% higher than that in control. We expect that the cultivation period of L. edodes will be shortened, and the yield increased in the medium replaced half of oak sawdust by douglas fir sawdust.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.3
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• pp.262-269
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• 2019

Purpose: As the importance of breastfeeding has been reinforced, human milk is often stored for practical reasons. Therefore, we evaluated optimal storage and processing methods for human milk from a nutritional standpoint. Methods: Human milk samples were collected between June 2017 and February 2018. Also, data about maternal information were collected. Human milk was analyzed for macronutrients and caloric content. The samples were subdivided into groups for nutrient analysis. The control group (fresh milk) was not stored or processed. The other groups (9 groups) consisted of samples analyzed based on different storage temperatures (room temperature, refrigerated, frozen), defrosting methods (bottle warmer, room temperature thawing, microwave oven), and storage period (1 week, 1 month, 2 months) and compared with the control group. Results: There was no statistically significant difference in the nutrient content of human milk among the collected samples. A significant change in the content of macronutrients in milk samples was observed under storage condition at different temperatures for 1 week with subsequent thawing with bottle warmer compared to fresh milk. Under storage at $-20^{\circ}C$ for 1 week with subsequent thawing with different defrosting methods, a significant change in the content of macronutrients in milk samples was observed compared to fresh milk. After storage at $-20^{\circ}C$ for different periods and thawing with a bottle warmer, a significant change in macronutrient content in milk samples was observed compared to fresh milk regardless of the storage period. Conclusion: Unlike previous guidelines, changes in macronutrient content in milk samples were observed regardless of the method of storing and thawing. Apparently, it is proposed that mothers should feed fresh human milk to their babies without storing.

• Journal of radiological science and technology
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• v.45 no.6
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• pp.491-502
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• 2022

The purpose of this study was to retrospectively investigate the upper and lower control limits of treatment planning parameters using EBT film based delivery quality assurance (DQA) results and to analyze the results of statistical process control (SPC) in helical tomotherapy (HT). A total of 152 patients who passed or failed DQA results were retrospectively included in this study. Prostate (n = 66), rectal (n = 51), and large-field cancer patients, including lymph nodes (n = 35), were randomly selected. The absolute point dose difference (DD) and global gamma passing rate (GPR) were analyzed for all patients. Control charts were used to evaluate the upper and lower control limits (UCL and LCL) for all the assessed treatment planning parameters. Treatment planning parameters such as gantry period, leaf open time (LOT), pitch, field width, actual and planning modulation factor, treatment time, couch speed, and couch travel were analyzed to provide the optimal range using the DQA results. The classification and regression tree (CART) was used to predict the relative importance of variables in the DQA results from various treatment planning parameters. We confirmed that the proportion of patients with an LOT below 100 ms in the failure group was relatively higher than that in the passing group. SPC can detect QA failure prior to over dosimetric QA tolerance levels. The acceptable tolerance range of each planning parameter may assist in the prediction of DQA failures using the SPC tool in the future.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.1
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• pp.131-148
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• 2010

Piglet health at weaning is compromised due to several stress factors. Following the ban of antibiotic growth promoters new alternatives are required to control these problems. This paper reviews the evidence available for the use of spray dried animal plasma (SDAP) as an alternative to antibiotics in weaning pigs. Data from 75 trials in 43 publications involving over 12,000 piglets (mean values) have been used to calculate the performance responses of piglets according to several factors including SDAP origin, protein source from the control diet being replaced, dose of inclusion, age and weight of the piglets at weaning, sanitary conditions and simultaneous use or not of medication. Although the use of SDAP of all origins results in positive responses, it appears that plasma from porcine origin has the highest efficacy. This could be explained by the specificity of its IgG against porcine pathogens. During the first week post-weaning the response to plasma appears to increase with the inclusion dose, although over the two-week pre-starter period an optimal inclusion level of 4-8% is suggested. SDAP improves feed efficiency more markedly when the piglets are challenged with an experimental infection or when feed does not contain medication, which could be indicative of a lower expenditure of energy and nutrients to build an immune response against the challenge. There is evidence supporting that SDAP IgG and other bioactive substances therein prevent the binding of pathogens to the gut wall and reduce the incidence of diarrhoea in the post-weaning phase. Overall, plasma can be postulated as an excellent alternative to in-feed antimicrobials for piglets in the post-weaning phase.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.1
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• pp.18-28
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• 1998

A laboratory experiment was made of a control of temperature oscillation in Czochralski convection. Numerical computation was also made to delineate the control of temperature oscillation. The suppression of temperature oscillation was achieved by varying the rotation rate of crystal rod ($\Omega=\Omega_0(1+A sin 2{\pi}ft/t_p)$), where A denotes the amplitude of rotation rate and f the frequency factor. Based on the inherent dimesionless time period of temperature oscillation ($t_p$), the suppression rate of temperature oscillation was characterized by the mixed convection parameter ($0.217{\leq}Ra/PrRe^2{\leq}1.658$). The optimal values of A and f were also scrutinized. To understand the suppression mechanism of temperature oscillation, the controls of isotherm($\theta$) and equi-vorticity($\omega$) were investigated.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.4
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• pp.267-275
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• 2004

This research is concerned with the development of a real-time adaptive PPF controller for the active vibration suppression of smart structure. In general, the tuning of the PPF controller is carried out off-line. In this research, the real-time learning algorithm is developed to find the optimal filter frequency of the PPF controller in real time and the efficacy of the algorithm is proved by implementing it in real time. To this end, the adaptive algorithm is developed by applying the gradient descent method to the predefined performance index, which is similar to the method used popularly in the optimization and neural network controller design. The experiment was carried out to verify the validity of the adaptive PPF controller developed in this research. The experimental results showed that adaptive PPF controller is effective for active vibration control of the structure which is excited by either impact or harmonic disturbance. The filter frequency of the PPF controller is tuned in a very short period of time thus proving the efficiency of the adaptive PPF controller.

• Korean journal of food and cookery science
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• v.24 no.6
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• pp.735-741
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• 2008

The principal objective of this study was to evaluate the quality characteristics of yogurt to which had been added extracts of low quality dried persimmons, in an attempt to expand the range of use of low-quality dried persimmons. In the results of our sensory evaluation, our optimal results were attained with the addition of 5 g of dried persimmon extracts, 90 g of water, 20 g of oligosaccharide, and 50 g of fructose at a specific level of 1000 mL. During the 20-day storage period, the pH value of the dried persimmon yogurt was lowest on the 15th day in the control group and the 20th day in the yogurt to which 0.5% extract had been added. The titratable acidity was lowest by a significant margin on the 10th day for all types of yogurt. Viscosity assays showed a stable level of acidity over different storage periods. The number of viable cells demonstrated a trend toward increase with passing time, and the number of viable cells in the dried-persimmon yogurt was higher than that in the control yogurt.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.6
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• pp.888-895
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• 2010

Riceyeotgangjung (RYG) with added spirulina was prepared with citron juice for masking of odor. Oil temperature for puffing was found to be $220^{\circ}C$ for frying dry rice based upon the results of expansion rate and color. RYGs with added spirulina (1, 2, and 3%) were prepared under the above conditions, and their physicochemical and sensory properties were examined under storage at $60^{\circ}C$ for 15 days. Moisture content of RYG decreased proportionally with the spirulina content and storage time. The hardness levels of the freshly made RYGs with spirulina were higher than that of control. During storage, the hardness of the control gradually increased, but those of the RYGs with spirulina gradually decreased, although no significant differences existed between the spirulina containing RYGs. Lightness and redness values in the Hunter color system decreased according to the spirulina content and storage time. Yellowness value also increased with the spirulina content and storage time. Phycocyanin and total phenolic content increased with spirulina content, but decreased with the storage period. Sensory evaluation results showed that RYG with 2% added spirulina received the highest scores for color, taste, overall acceptability, and intention of purchase. As a result, the optimal addition amount of spirulina to RYG is recommended to be 2%.

• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.216-222
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• 2003

In order to develop effective control methods for Bakanae disease caused by Gibberella fujikuroi (Saito) Ito during rearing of rice seedlings, we investigated the disease resistance of 15 rice varieties to G. fujikuroi and control effect of six seed disinfectants, and tried to improve the using methods of the seed disinfectants. Disease resistance was tested by investigating the disease incidence on each rice cultivar grown in rice seedling box infested with or not infested with G. fujikuroi at 30 days after sowing seeds and 20 days after heading date. The results showed that Hwayongbyeo, Dongjinbyeo, Hwoanbyeo, Nonghobyeo, Nampyeongbyeo, and Hwojinbyeo were resistant G. fujikuroi, meanwhile Keulubyeo, Sobibyeo, Odaebyeo, Junambyeo, Samchonebyeo, Sangjubyeo, and Hwabongbyeo were susceptible. Three seed disinfectants, prochloraz, fludioxonil, and carproamid + thiram + fludioxonil controlled Bakanae disease of rice very well, while bonomyl + thiram, thiophanate-methyl + thiram and thiophanate-methyl + triflumizole did not suppress the disease enough. Water temperature was turned to be an important factor for controlling the disease by treating seed disinfectants. Prochloraz showed 61% control value on the disease at $10^{\circ}C$, but it showed above 95% control value at the range of $30-35^{\circ}C$. It was confirmed that the control effect of seed disinfectants increased with increasing water temperature. Meanwhile soaking period of rice seeds in the suspension of seed disinfectants and chemical dosage had no high relation to control the disease. This results suggest that rice varieties, water temperature, and optimal selection of suitable seed disinfectants are very important to control Bakanae disease effectively.