• Title/Summary/Keyword: $2^k$ factorial design

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Isolation and Cultural Properties of Acetic Acid Bacteria for Production of Onion Vinegar

  • Jang, Jae-Kweon;Choi, Young-Jin;Chung, Myong-Soo;Park, Hoon;Shim, Kun-Sub;Park, Young-Seo
    • Food Science and Biotechnology
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    • v.18 no.4
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    • pp.939-947
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    • 2009
  • In order to produce vinegar using onions, 12 acetic acid bacteria were screened from the juice of fallen peaches, and a strain showing the highest acetic acid productivity among them was selected and identified as Acetobacter tropicalis No. 22. The culture broth containing 2.5%(w/v) of initial sugar concentration showed maximum acetic production after 10 days of cultivation, and the acetic acid was produced at the highest rate and reached the maximum acidity after 2 to 6 days of cultivation when the residual sugar and the ethanol concentration were in the range of 1.6 to 2%(w/v) and 0.6 to 1.8%(v/v), respectively. Also optimum conditions for acetic acid production by response surface method using the fractional factorial design with 3 variables and 5 levels were involved with initial ethanol content of 4.67%(v/v), initial acidity of 0.03%, and initial glucose concentration of 2.35%(w/v) and predicted level of acetic acid production at these conditions was 3.77%.

Optimization of Extraction Condition for Black Tea with Chamomile (Anthemis nobilis) by Response Surface Methodology (반응 표면 분석에 의한 캐모마일(Anthemis nobilis) 첨가 홍차의 최적 추출조건)

  • Lim, Oh-Jun;Byun, Kwang-Ihn;Lee, Byoung-Gu
    • Korean journal of food and cookery science
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    • v.23 no.6
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    • pp.954-960
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    • 2007
  • The study was designed to determine optimum extraction conditions, by the factorial design of 3 variables and 3 levels using an a RSM program. To determine the optimal conditions for the extraction of black tea with chamomile, the experimental design was applied. The independent factors were the extraction temperature ($60^{\circ}C$, $80^{\circ}C$, $100^{\circ}C$), extraction time (2 min, 4 min, 6 min), and chamomile addition (0.3%, 1.0%, 1.7%). By the RSM (response surface methodology) analysis of the black tea with chamomile extraction, we found that the extraction temperature greatly affected the extraction yield, brix, pH, and reducing sugar, caffeine, theobromine and theophillin contents. The optimum extraction time, temperature, and chamomile content were 4 min, $90^{\circ}C$, and $1.6{\sim}1.7%$, respectively.

Improving sugarcane bagasse quality as ruminant feed with Lactobacillus, cellulase, and molasses

  • So, Sarong;Cherdthong, Anusorn;Wanapat, Metha
    • Journal of Animal Science and Technology
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    • v.62 no.5
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    • pp.648-658
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    • 2020
  • The objective of the study was to evaluate the effects of Lactobacillus, cellulase, and molasses on chemical composition, fermentation qualities, and microorganism count of sugarcane bagasse silage after 30-days fermentation. The treatments were arranged according to a factorial arrangement (2 × 2 × 2) + 1, in a complete randomized design. The first factor consisted of two levels of Lactobacillus casei TH14 (TH14, 0 and 0.05 g/kg fresh matter; the second factor consisted of two levels of cellulase enzyme (C, 0 and 104 U/kg fresh matter); and the third factor consisted of two levels of molasses (M, 0 and 5 g/ 100 mL distilled water). A treatment (+1) referred to the use of rice straw without any treatments. The result showed that dry matter increased by 4% and neutral detergent fiber decreased by 2% of sugarcane bagasse when ensiled as a combination of additives as compared to untreated sugarcane bagasse. The pH and ammonia nitrogen were significantly dropped to 3.5 and 2.3 g/kg dry matter. Furthermore, lactic acid was increased by 64% when compared to untreated sugarcane bagasse, respectively. Lactic acid bacteria count was increased by 28% as compared to untreated sugarcane bagasse. Based on this experiment, fermenting with L. casei TH14, cellulase, and molasses in combination resulted in the promotion of the best qualities of sugarcane bagasse silage.

The Effects of Seasons (Hot/Dry and Cool/Humid) on Thermoregulatory Responses of Male and Female Bali-Cattle Working in the Field

  • Kasa, I.W.;Hill, M.K.;Thawites, C.J.;Baillie, N.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.1
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    • pp.64-69
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    • 1997
  • A study was conducted on the effects of ploughing on physiological responses of male and female Bali-cattle. A $2{\times}2{\times}6{\times}8$ factorial design (2 seasons, 2 sexes, 6 days and 8 consecutive time of measurements every 30 minutes) was employed. Responses during the cool/humid season were lower than hot/dry; respiration rate (RR) was 52 vs 75/min, rectal temperature(RT) was 39.1 vs $39.5^{\circ}C$ and skin temperature (ST) was 37.1 vs $37.6^{\circ}C$. Within sexes, males were less tolerant than females in that their RR (66 vs 61 breath/min), RT (39.4 vs $39.2^{\circ}C$) and ST (37.6 vs $37.1^{\circ}C$) were each higher than females during work. With increasing time, during the average 2.5 h working period gradual increases in RR, RT and ST were recorded and the overall increases of 84 breath/min, $1.9^{\circ}C$ and $13.8^{\circ}C$ respectively (p < 0.001). Packed cell volume (PCV) data indicated significant difference between sexes, time and season (p < 0.001, p < 0.05 and p < 0.001 respectively). Within time (before and after 2.5 h working) the PCV decreased from 27.4 to 25.6%.

Optimization of Extraction Conditions for Hot Water Extracts from Chrysanthemum indicum L. by Response Surface Methodology (반응표면분석법을 이용한 감국(甘菊) 열수 추출물의 추출조건 최적화)

  • Yun, Ok-Hui;Jo, Jeong-Sun
    • Korean journal of food and cookery science
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    • v.23 no.1 s.97
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    • pp.1-8
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    • 2007
  • Extraction conditions were optimized using response surface methodology for preparing high-quality, hot water extracts from cultivated Chrysanthemum indicum L. petals. A fractional factorial design was applied to investigate the effects of added sample ratio ($X_1$), extraction temperature ($X_2$) and extraction time ($X_3$) variables on extract properties, such as, soluble solid contents ($Y_1$), sugar content ($Y_2$), ?E ($Y_3$), turbidity ($Y_4$), total phenol ($Y_5$) and DPPH ($Y_6$). Second-order models were employed to generate a 3-dimensional response surface for dependent variables and their coefficients of determination ($R^2$) ranged from 0.8408${\sim}$0.9914. The range of optimum conditions at $80^{\circ}C$ extraction for maximize characteristics of hot water extracts was 2.3${\sim}$2.7 g and 9.2${\sim}$11.2 hr.

Evaluation of Oxalic Acid Pretreatment Condition Using Response Surface Method for Producing Bio-ethanol from Yellow Poplar (Liriodendron tulipifera) by Simultaneous Saccharification and Fermentation (바이오에탄올 생산을 위한 백합나무(Liriodendron tulipifera)칩의 동시당화발효 및 Response Surface Method를 이용한 옥살산 전처리 조건 탐색)

  • Kim, Hye-Yun;Lee, Jae-Won;Jeffries, Thomas W.;Choi, In-Gyu
    • Journal of the Korean Wood Science and Technology
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    • v.39 no.1
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    • pp.75-85
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    • 2011
  • The main purpose of this study is to evaluate the potential of producing bioethanol from yellow poplar ($Liriodendron$ $tulipifera$) wood chips by oxalic acid pretreatment and to examine the pretreatment conditions by response surface methodology (RSM). Based on $2^3$ factorial design, adjusted variables were reaction temperature ($^{\circ}C$), residence time (min), and acid loading (g/g), and a series of distinct 15 experimental conditions was organized with duplication at central point (total 16 performances). After pretreatment, simultaneous saccharification and fermentation (SSF) was subjected on solid fraction with yeast strain $Pichia$ $stipitis$. Maximum ethanol yields of the most samples were measured at 72 hours and applied to RSM as a dependent variable. 9.7 g/${\ell}$ of ethanol was produced from the solid pretreated at $180^{\circ}C$ for 40 min with 0.013 g/g of oxalic acid loading. According to the response surface methodology, it was determined that the temperature is the most governing factor via statistic analysis.

A Study on Detection of Outliers and Influential Observations in Linear Models

  • Kang, Eun M.;Park, Sung H.
    • Journal of Korean Society for Quality Management
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    • v.16 no.2
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    • pp.18-33
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    • 1988
  • A new diagnostic statistic for detecting outliers and influential observations in linear models is suggested and studied in this paper. The proposed statistic is a weighted sum of two measures ; one is for detecting outliers and the other is for detecting influential ovservations. The merit of this statistic is that it is possible to distinguish outliers from influential observations. This statistic can be used for not only regression models but also factorial design models. A Monte Carlo simulation study is reported to suggest critical values for detecting outliers and influential observations for simple regression models when the number of observations is 11. 21, 31, 41 or 51.

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A NOVEL METHOD FOR REFINING A META-MODEL BY PARETO FRONTIER (파레토 프론티어를 이용한 메타모델 정예화 기법 개발)

  • Jo, S.J.;Chae, S.H.;Yee, K.J.
    • Journal of computational fluids engineering
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    • v.14 no.4
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    • pp.31-40
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    • 2009
  • Although optimization by sequentially refining metamodels is known to be computationally very efficient, the metamodel that can be used for this purpose is limited to Kriging method due to the difficulties related with sample points selections. The present study suggests a novel method for sequentially refining metamodels using Pareto Frontiers, which can be used independent of the type of metamodels. It is shown from the examples that the present method yields more accurate metamodels compared with full-factorial optimization and also guarantees global optimum irrespective of the initial conditions. Finally, in order to prove the generality of the present method, it is applied to a 2D transonic airfoil optimization problem, and the successful design results are obtained.

Biofortification of mushroom (Pleurotus floridanus) using calcium based supplements

  • Odiketa, J.K;Whitehall, S.;Adedokun, O.M.
    • Journal of Mushroom
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    • v.18 no.4
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    • pp.287-291
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    • 2020
  • The nutritional value and yield of mushrooms depend on the substrate on which it is grown. This study sought to biofortify Pleurotus floridanus with calcium supplements and assess its effect on the yield and calcium levels. The experiment was set up in a 2 × 5 factorial and replicated thrice in a completely randomized design. Two calcium supplements, OML and OMW, were added to two growth media. The examination of total dry weight yield showed that calcium supplements OML and OMW in the sawdust medium containing wheatbran in the ratio 1:10 had a mean value of 4.37 g, which was significantly higher (P < 0.05) than that in the control (1.29 g). However, in the sawdust-only medium, there was no significant difference (p > 0.05) in the application of treatments. No significant difference (p > 0.05) was observed between the calcium types in both growth media. The mineral analysis showed that calcium levels were increased in harvested mushrooms with the addition of calcium OML and OMW to the growth media.

The effects of female applicant's facial attractiveness and feminine-masculine clothing image on job performance evaluation and hiring decision (여성 응모자의 얼굴 매력성과 의복의 여성성/남성성이 직무수행능력 판단과 고용의사결정에 미치는 영향)

  • Kim, Jeongmi;Chung, Myung-Sun
    • The Research Journal of the Costume Culture
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    • v.21 no.3
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    • pp.401-412
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    • 2013
  • The purpose of this study was to investigate the effects of female applicant's facial attractiveness and feminine-masculine clothing image on job performance evaluation and hiring decision. The research design of study consisted of 3(facial attractiveness high, middle, low)${\times}$2(feminine and masculine clothing image) factorial design. The subject consisted of 243 persons whose occupation were mid-sized companies' administrator in Gwangju and Seoul City. The data were analyzed by factor analysis, Duncan test, ANOVA, t-test. The results of this study were as follows. First, three factors emerged to account for the job performance evaluation. These factors were given the titles of task performance, cooperation and self-management factors. Second, applicant's facial attractiveness exerted significant positive effect on self-management and significant negative effect on cooperation. Third, applicant's facial attractiveness exerted significant effect on hiring decision. Finally, the interaction effect of female applicant's facial attractiveness and feminine-masculine clothing image on job performance evaluation and hiring decision were not significant.