• 한국식품영양과학회지
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• 제30권3호
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• pp.466-470
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• 2001

Response surface methodology was used for monitoring extraction conditions, based on quality properties of old pumpkin extracts. Hunter's color L value of extracts was maximized at 101℃, 2.6 hr and decreased gradually after maximum point. The polynomial equation for Hunter's color L value showed 10% of significance level and 0.8799 of R². Hunter's color a value was minimized at 117℃, 3.9 hr and R² of polynomial equation was 0.9852 within 1% significance level. Hunter's color b value and ΔE value increased as the extracting temperature and time increased. Extraction yield of old pumpkin was maximized at 110℃, 4 hr and increased in proportional to the extracting temperature and time, but decreased after 113℃ and 2 hr. Viscosity of pumpkin extracts were maximized at 120℃, nearly 3 hr. R² of polynomial equations for yield, viscosity and sugar content were 0.9532, 0.9812 and 0.8869, respectively. Optimum ranges of extraction conditions for quality properties of old pumpkin were 102∼109℃, 2.5∼3.5 hr, respectively. Predicted values at the optimum extraction condition agreed with experimental values.

• 한국미생물·생명공학회지
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• 제21권6호
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• pp.609-614
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• 1993

The optimum conditions for the submerged mycelial culture of Lentinus edodes SR-1 were elucidated to be incubation temperature of 25C, initial pH 4.0, agitation of 300 rpm, inoculation of 10.0%(v/v), and aeration of 1.0 v/v/m in TGY medium. The optimum c/n ratio and economic yield coeffcient for the submerged mycelial culture were 13.1:1 and 0.45 respectively. As the plant growth hormones test, SCM medium containing 0.5ppm of 2,4-dicholorophenoxyacetic acid increased mycelial yield in 1.1%, but 6-benzylaminopurine was not effective.

• 한국식품영양과학회지
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• 제21권4호
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• pp.377-380
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• 1992

To produce economically important acid with pear juice, an acetic acid bacterium was selected from many isolated acetic acid bacteria. The alcohoic fermentation was conducted by inoculating pear juice with Saccharomyces cerevisiae ATCC 4124, and then the pear vinegar was prepared by batch cultivation in flaskes with the isolated Acetobacter sp. The optimum conditions for high yield of acetic acid were studied experimentally in the batch shake flask . For seed purposes the Acetobactor sp. was cultivated for 2 -days and transferred to the acid production medium . Optimum alcohol concentration, initial acidity and temperature for the acid production were 8.0% , 2.0% and 28$^{\circ}C$, respectively. Under the same conditions, the addition of yeast extract (1%) was observed to produce relatively high yield of acetic acid.

• 한국식품저장유통학회지
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• 제9권4호
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• pp.396-399
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• 2002

An attempt was made in this study to investigate the optimum extracting time from meat with bone of goat and the nutritional component of its extract. for the trials, the mixtures of meat with bone and water were adjusted to the ratios of five to four by weight and extracted for 6, 9 and 12 hours at 120$\^{C}$ under autoclave. Judging from the content of mineral and amino acid, nonenzymatic browning and yield, the optimum extracting time was 9 hours. The major components of mineral were composed of 47.7mg％ potassium, 12.7mg% calcium, 150.0mg% sodium, 105.3mg% phosphorus and 0.5mg% iron, and of amino acids composed of 1,308.0mg% glutamic acid, 1,464.2mg% glycine, 750.2mg% alanine and 828.lmg% proline in extract. The yield of extract was 32.1 percentage by dry basis.

• 한국기계연구소 소보
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• 통권20호
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• pp.71-78
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• 1990

This investigation was undertaken to establish the technologies of grain refinement and modification, and to characterize material properties, essential for high quality aluminum alloy castings. Grain refinement seldom changed DAS and eutectic Si size, but largely decrease grain size. The variations of grain size induced by grain refinement had a great influence on the elongation without changes in the tensile strength or yield strength. The optimum Ti level lies between 0.1% and 0.16% to achieve the best possible mechanical properties. DAS and grain size were little affected, but eutectic Si size was greatly refined by modification. The variation of eutectic Si size had a great effect on the elongation, impact value, fracture toughness and fatigue crack propagation rate without changes in the tensile strength or yield strength. The Sr content of 0.015% is optimum to modification.

• Journal of Biosystems Engineering
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• 제43권4호
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• pp.362-368
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• 2018

Purpose: Self-sufficiency in paper production is desired in Nigeria. This study was aimed at evaluating the performance of a locally fabricated batch pulp digester. Methods: The pulp yields of sheaths generated as waste in the production of bamboo (Bambusa vulgaris) laminates were determined at different liquor concentrations and treatment time after preliminary experiments to ascertain the conditions under which the sheath started to pulp. Moreover, the optimum pulping conditions and fiber characteristics were determined and estimated, respectively, to ascertain the pulp fiber suitability for paper production. Results: An optimum pulp yield of 65.1% was obtained at 50% NaOH and 25% $Na_2S$ liquor concentration (w/w) when the cooking time was 4 h. The results of fiber characterization of the pulp indicated an average fiber length of 2.19 mm with a low Runkel ratio of 1.63, both of which signify the suitability of the pulp for medium quality paper production. Conclusions: Softwood pulp can be blended with the fibers to improve the strength of the produced paper; further investigation should be carried out to use other non-woody plants for pulp and papermaking.

• 동력기계공학회지
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• 제21권5호
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• pp.86-91
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• 2017

Friction Stir Welding (FSW) is useful technique to join aluminum alloy with energy efficient and environment friendly. In this paper, the design of experiment with three-way factorial design was adopted for optimum conditions of welding variables in the FSW of Al 6061 alloy. Tools of shoulder diameter of 9, 12, 15 mm and pin length of 1.5 mm were used. Also the material's dimension for welding were $2{\times}100{\times}150mm$, and the tensile specimens were worked by water-jet technique. Welding variables were shoulder diameter, rotating speed and travel speed of tool. From the results of this work, the welding factor influenced on yield strength most was travel speed and the optimum condition for FSW was predicted as the shoulder diameter of 15 mm, welding speed of 500 mm/min and rotating speed of 2,000 rpm. Also the presumption range of yield strength at optimal condition of reliability 99% was estimated to $207.19{\pm}9.91MPa$.

• 한국산학기술학회논문지
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• 제13권6호
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• pp.2697-2701
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• 2012

안티퓨즈 MOS 커패시터를 기반으로 제작된 OTP 소자의 수율은 프로그램 과정에서 입력 저항(Rin)값과 통과 트랜지스터(Pass Tr)의 크기, 데이터 읽기 과정에서 읽기 트랜지스터(Read Tr)와 읽기 전압에 영향을 받는다. 따라서 수율에 영향을 주는 요소를 분석하기 위해 여러 가지 실험 조건을 달리하여 각각의 조건에 대해 블로잉 후 실효소자의 저항 특성에 대한 풀 맵(full map) 데이터를 얻어 OTP 소자가 어떻게 동작하는지를 분석하여 수율 개선에 필요한 최적 조건을 연구하였다. 최적 조건은 입력저항이 $50{\Omega}$, 통과 트랜지스터의 W값이 $10{\mu}m$, 읽기 전압이 2.8 V 일 때이다.

• 한국식품영양과학회지
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• 제33권1호
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• pp.225-228
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• 2004

반응표면분석법(RSM)을 활용하여 유동층과립기의 흡입공기온도, 물의 투입비율, 분무압력 등이 분유의 과립화에 미치는 영향을 분석하였다. 분유의 과립화 수율은 물의 투입 비율에 많은 영향을 받고 있음을 알 수 있었으며, 겉보기밀도 및 다짐 밀도는 분무압력에 크게 영향을 받고 있음을 보여주었다. 분유의 유동층 과립화의 최적조건은 흡입공기온도6$0^{\circ}C$, 물의 투입비율 16 mL/min, 그리고 분무압력 2.1 bar이었으며, 이때 과립화 수율은 94.0%, 겉보기밀도는 0.350 g/㎤, 그리고 다짐밀도는 0.446 g/㎤로 각각 예측되었다.

• 한국식품영양과학회지
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• 제23권1호
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• pp.156-163
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• 1994

To investigate the optimum conditions of seaweed Mooks prepared with sea mustard (Indaria pinnatifida) and sea tangel(Laminaria japonica), pH, viscosity , yield and jelly strength were studied on the sol and /or gel (Mook ) made from homogenized seaweeds. Solubilization conditions of homogenized seaweeds were heating at $65^{\circ}C$ for one hour after mixing homogenized seaweed with 1 % $K_2$HPO$_4$ by 1 ; 1 (v/v) . Gelation conditions were 24 hrs by natural permeation of Ca++ into the sol in three times (v/v) of 1 % CaCl$_2$ solution to solubilized seaweed passed through 60 mesh of sieve. There are generally no relationship between viscosity of solubilized seaweed and jelly strength of Mook produced by gelation of the sol in CaCl$_2$ solution . Jelly strength of sea mustard Mook was more than 500g/$\textrm{cm}^2$ , yield was 87.5% of the solubilized and filtrated seaweed . Jelly strength and specific gravity of sea tangle Mook were higher those of sea mustard Mook, while its yield was lower than that of sea mustard Mook.