• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.2
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• pp.248-255
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• 2013

The objective of this study is to optimize the Metal Injection Molding(MIM) process with design of experiments(DOE) and numerical analysis. To derive the optimal process condition, experiment or numerical analysis was performed under various process conditions. To analyze the interaction among influential factors contributing to the temperature at flow front and response surface in MIM, both central point and axial point were added to the full factorial design with 2 levels and 5 factors and then their impacts on response variable in 43 experimental conditions were analyzed and the significance was evaluated. As a result, sprue, runner, and gate were completely filled in about 0.247 seconds after injection, the front part of the green body was filled in about 0.3344 seconds, the green body except gate, etc changed to almost solid state in about 3.29 seconds, the Packinging pressure was completed in about 6.29 seconds, and the green body inside and outside and sprue, etc became solid in 13.2 seconds. The impact of individual or reciprocal action of factors on the temperature at flow front was analyzed through regular probability, test statistics, main effect, and interaction effect. As a result, of a total of 31 combinations of factors, 9 unit factors and reciprocal actions were significant, and the screening was also possible. A proper regression equation was drawn with regression analysis and response surface design on the response variable of temperature at flow front, and the applicability could be verified.

• Korean Journal of Poultry Science
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• v.22 no.3
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• pp.179-188
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• 1995

In Experiment 1, microbial assays were conducted on 57 feed ingredient samples to determine the content of total folic acid using Lactobacillus casei(ATCC 7469). Folic acid contents of feed samples pretreated with conjugase, ${\alpha}$-amylase, and a mixture of protease(Pronase)were corn, 09${\pm}$1.18($\pi$g${\pm}$SD); fish meal, 23.05${\pm}$1.27; milo, 29.34${\pm}$0.55; bakery meal, 25.80${\pm}$6.93; meat and bone meal, 56.76${\pm}$4.97; wheat middlings, 85.14${\pm}$2.56; and soybean meal, 193.97${\pm}$3.98. Experiments 2 and 3 were conducted to determine the effects of dietary supplemental folic acid and methionine on the performance of starting broiler chicks for 18 days. Four levels of dietary folic acid(0.24. 0.54,1.14 and 2.34mg/kg) and four levels of dietary methionine(0.45, 0.53,0.61, and 0.69%) were fed in a factorial design. The basal diet was based on corn, isolated soybean protein, meat and bone meal, and fish meal. It contained adequate amounts of all nutrients except methionine and folic acid in both experiments. Increased growth rate was observed in chicks fed the basal diet supplemented with either folic acid or methionine. Total dietary folic acid and methionine plus cysteine requirements for optimum growth were estimated to be 1.80 mg/kg and 0.89% in Experiment 2, and 1.47 mg/kg and 0.91% in Experiment 3, respectively. There were interactions between dietary folic acid and methionine on weight gain in both experiments. Chicks fed diets containing 2.34 mg folic acid /kg tended to display slow growth rate in both experiments. There was a significant linear feed conversion response to folic acid in Experiment 2, and a significant quadratic feed conversion resuonse to methionine in Experiment 3. There were both linear and quadratic liver folic acid responses to dietary folic acid in both experiments. There was no indication that dietary methionine had any effect on liver folic acid content. The incidence of tibial dyschondroplasia increased with increasing supplemental methionine, but were no significant differences detected at 5% level.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.4
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• pp.473-478
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• 2004

Processing and storage of the silage from agricultural by-products were studied in two experiments. The first experiment was conducted to investigate the chemical composition and degradability of various silages with varying ensiling times. The experiment was a 5$\times$3 factorial design, completely randomized, with factor A as the different formulated mixtures by varying level of urea addition (0, 0.5, 1.0, 1.5 and 2.0%) and factor B as the time of ensiling. Chemical composition changed little with time and varied only slightly with levels of urea in the mixtures. Dry matter (DM) degradability increased with increasing cassava levels while crude protein degradability and pH level increased with increasing urea addition. By using 'Flieg point', which relates to organic acid yields, there were no significant difference among ensiled mixtures and times of ensiling. Therefore it can be concluded that the 5th silage formulation is the most appropriate since its DM and crude protein (CP) degradability were highest. The second experiment was carried out to determine the quality of the 5th silage mixtures (from the previous trial) after being stored for up to 6 months. The experiment was a complete randomized design with samples taken at monthly intervals up to 6 months and subjected to laboratory and degradability analyses. The results showed no significant (p>0.05) difference in chemical composition except for increased neutral detergent fiber and acid detergent fiber percentage in association with increasing storage time. There were no significant (p>0.05) differences in 'Flieg point' among times of storage. In conclusion, this experiment showed that the silage from agricultural by-products can be stored for more than 6 months.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.381-384
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• 2002

Response surface methodology (RSM) was successfully applied to optimize for the production of Ganoderma lucidum in batch fermentations using the whey (40,000 mg latose/L) as substrate. This study was performed according to the central composite design (CCD) with respect to pH and temperature, where the designed intervals were 3.3$22.9^{\circ}C$$37.1^{\circ}C$, respectively. A second-order factorial design of the experiments was used to build empirical models providing a quantitative interpretation of the relationships between the two variables. The optimum conditions to maximize the production of G. lucidum were pH 4.2 and $28.3^{\circ}C$. At optimum conditions, the mycelial dry weight (MDW) and residual soluble COD (SCOD) were simultaneously used to evaluate the biokinetic coefficients assocoated with substrate inhibition model by nonlinear least squares method with 95% confidence interval. The. maximum microbial growth rates (${\mu}m$), half saturation coefficient ($K_s$), and the inhibition substrate concentration ($K_{is}$) were determined to be 0.095 l/hr, 128,000 mg SCOD/L and 49,000 mg SCOD/L, respectively. And the microbial yield coefficient (Y), biomass decay rate coefficient ($K_d$), and the maintenance energy coefficient ($m_s$) were determined to be 0.37 mg MDW/mg SCOD, 0.001 1/hr, and 0.0015 1/hr, respectively.

• Korean Journal of Poultry Science
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• v.35 no.4
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• pp.399-405
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• 2009

Two experiments were conducted to establish the basic data of feeding system in cross-bred Korean native chicks. A total of seven hundred twenty chicks were replaced the 36 floor pen for the first five weeks with $3{\times}3$ factorial design in Experiment 1. Four hundred eighty of five weeks old chicks were raised from six to ten weeks of age with $3{\times}2$ factorial design in Experiment 2. Dietary ME and CP were formulated to contain 3,000, 3,050, 3,100 kcal/kg and 21, 22, 23%, respectively in Experiment 1 and 3,050, 3,100, 3,150 kcal/kg and 18, 19% in Experiment 2. Weight gain, feed intake were measured and calculated the feed conversion. Blood were collected and analyzed at the end of experiments. In Experiment 1, weight gain showed significantly higher in 3,050, 3,100 kcal/kg treatments than 3,000 kcal/kg treatment (P<0.05), but was not different in CP treatments. Feed intake was statistically high in 3,000 kcal/kg treatment compared with 3,050 and 3,100 kcal/kg ones (P<0.05), and more increased in 21% CP treatments compared to that of 22 and 23 CP treatment (P<0.05). Feed conversion of birds fed 3,050 and 3,100 kcal/kg diet showed much lower than 3,000 kcal/kg treatments (P<0.05). FCR was signicantly improved (P<0.05) in chicks fed diets containing 21 and 22% CP as compared to that fed 20% CP. Blood protein, glucose, and total cholesterol tended to increase in high energy and diet treatments. Blood HDL was increased as dietary energy increased, whereas LDL increased in low CP treatments. In Experiment 2, weight gain was not consistent between treatments, but more increased in 18% CP treatments compared to that of 19% CP treatment from six to ten weeks old in cross bred chicks (P<0.05). Feed intake was similar to the result of weight gain, but more increased in 19% CP treatment than 18% CP treatment (P<0.05). There were no statistically difference in FCR, but seemed to improve as dietary ME increased. Blood total protein and glucose increased as dietary CP was high, but triglyceride and HDL increased in high versus low ME (P<0.05). The results of these experiments suggested that optimum dietary ME and CP, were 3,050, 3,150kcal/kg and 22, 19% for the first five weeks and second one, respectively.

• Applied Biological Chemistry
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• v.21 no.1
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• pp.40-50
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• 1978

Effects of Zn, P and Fe on Cd uptake and accumulations by tomato (Lycopersicum esculentum Mill) and also their interactions on the uptake of Zn, Fe, Mn, P and Cd were investigated using batch type solution culture technique. Experiment 1 was a factorial scheme with 3 levels of Zn (0, 0.5, 2.5 ppm) and 3 levels of Cd (0, 0.2, 1.0 ppm). At 1.0 ppm Cd, significant yield reduction of dry matter and visual toxicity symptoms (yellowing and necrosis) of Cd was observed for all zinc levels. At this Cd level, increasing Zn treatment from 0 to 2.5 ppm increased Cd concentration from 199 to 235 ppm in leaves and from 124 to 145 ppm in stems. Similarly, Cd treatment did not suppress Zn uptake in leaves, and rather significantly increased in stems. Fe concentrations in leaves and stems were significantly reduced due to Cd treatment while Mn were increased by both Zn and Cd treatment. The results of experiment 2 with 3 levels of P (0.5, 2.0, 4.0m Mol) and 3 levels of Cd (0, 1.0, 2.0 ppm) in a factorial scheme also showed a growth reduction and visual toxic symptons from 1.0 ppm Cd level. Increasing P treatment tend to increase Cd concentrations in leaves and stems although it was not statistically significant. Increasing P concentration due to Cd treatment could be the 'concentration' effect as a result of reduced growth, while there was significant decrease in Fe concentration due to Cd treatment in spite of possible 'concentration' effect. Mn concentration was increased at 1.0 ppm Cd level and then dropped at 2.0 ppm Cd level. Zu concentration in leaves and stems showed significant increase as Cd treatment increased as observed in experiment 1. Experiment 3 had 3 levels of Fe (0.5, 1.0, 2.0 ppm) and 3 levels of Cd (0, 0.8, 1.6 ppm) treatments in a factorial design. Significant growth reduction and visual toxic symptoms as observed in experiment 1 and 2 were also observed from 0.8 ppm Cd level. Increasing Fe treatment obviously alleviated toxic symptoms, improved growth and significantly increased dry matter yield. At 0.8 ppm Cd treatment level, increasing Fe treatment from 0.5 to 2.0 ppm significantly decreased Cd concentration from 141 to 92 ppm in leaves and from 101 to 46 ppm in stems. At 1.6 ppm Cd treatment level the decrease was from 224 to 167 ppm in leaves and from 124 to 109 ppm in stems. As in the case of experiment 1 and 2, Fe concentration in leaves and stems were reduced as Cd treatment increased to 1.6 ppm at 0.5 and 1. 0 Fe treatment levels, whereas at 2.0 ppm Fe level, Cd treatment increased Fe concentration in leaves and stems showing significant interactions of Fe and Cd on Fe uptake. Cd effect on Zn and Mn showed similar results to experiment 1 and 2 and Fe treatments reduced Zn and Mn concentrations in plant tissue. The results of 3 experiments show that P and Zn did not manifest suppressive effect on Cd uptake, Fe significantly demonstrated it. Fe also alleviated Cd toxicity symptoms significantly in terms of visual symptoms and dry matter yield. Visual toxicity symptoms were definitely related to Fe status in plant tissue as well as possible physiological effect of Cd itself, and the results suggest that Fe requirement for normal growth increase as Cd element is present in plant tissue. Zn accumulated more in stems than in leaves whereas Cd, Fe and Mn showed the opposite trend in all experiments.

• Journal of Animal Science and Technology
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• v.58 no.6
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• pp.19.1-19.7
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• 2016

Background: Cowpea (Vigna unguiculata [L.]) is a legume cultivated throughout most tropical countries and is valued as food and feed for human and livestock respectively. The search for an improved cowpea variety has been on-going with the aim of improving traits such as grain yield, drought and pest resistance. But no information exist on the feeding value of these improved varieties. Phosphate (P) fertilizer application is recommended to augment grain yield in grain legumes but data on the effect of P fertilizer on haulm quality is limited. Results: Two separate experiments were conducted to determine the effect of P fertilizer dose on the nutritive value of haulms from different cowpea varieties (V). In experiment 1, effect of three P doses (30, 60 and 90 kg $P_2O_5/ha$) on in vitro gas production (IVGP) characteristics, concentrations of digestible organic matter (DOM), crude protein (CP), acid detergent fiber (ADF) and neutral detergent fiber (NDF) of haulms from five cowpea varieties (Zaayura-SARC 4-75, Songotra-IT97K-499-35, Hewale-IT93K-192-4, IT99K 573-1-1 and Asomdwe-IT94K-410-2) were investigated using the $3(P){\times}5(V)$ factorial treatment arrangements in a completely randomized design. In experiment 2, the effects of two P doses (30 and 90 kg $P_2O_5/ha$) and two varieties (Zaayura-SARC 4-75 and Hewale-IT93K-192-4) on the voluntary feed intake, live weight, haematology and carcass characteristics of Djallonke lambs were also assessed using a $2(P){\times}2(V)$ factorial treatment arrangement. The $V{\times}P$ interaction significantly affected CP, NDF and ADF with CP concentration increasing with increase in P doses in Zaayura-SARC 4-75 and Asomdwe-IT94K-410-2. Whilst an increase (P < 0.05) in NDF was observed in Songotra-IT97K-499-35and Asomdwe-IT94K-410-2 as P doses increased, the other V only increased from P dose 30 to 60 kg/ha and declined at P dose 90 kg/ha. The ADF decreased (P < 0.05) with increase in P dose for all V with the exception of Songotra-IT97K-499-35. There was a significant V effect on DOM with the highest reported in Zaayura-SARC 4-75 (43.44 %). Daily DM intake, carcass length and blood urea nitrogen of the lambs were significantly affected by the V x P interaction. There was a significant V effect on globulin and P effect on live weight at slaughter, dressed weight, chuck, leg, loin, rib and flank and liver and lungs. Conclusion: It can be concluded that nutrient concentrations of cowpea haulms were positively influenced by different P dose and varieties with favorable effects on growth, haematology and carcass composition of lambs. Varieties Zaayura-SARC 4-75 and Hewale-IT93K-192-4 at P dose at 90 kg/ha are recommended to enhance growth performance and carcass yield of Djallonke lambs.

• Journal of Convergence for Information Technology
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• v.12 no.3
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• pp.132-140
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• 2022

This study was conducted to identify the optimal lotion manufacturing conditions with decursin and decursinol angelate of Angelica gigas Nakai extraction. Lotion was confirmed that it had viscosity (5,208±112 cPs), assay (99.71±1.01%), and pH (5.62) for 3 months. The optimization of manufacturing conditions of mixing 4 for lotion formulation were made by 22+3 full factorial design. Mixing temperature (40-80℃) and mixing time (10-30 min) were used as independent variables with three responses(assay, pH, and weight variation) as critical quality attributes (CQAs). The model for assay and weight variation identified a proper fit having a determination coefficient of the regression equation (about 0.9) and a p-value less than 0.05. Estimated conditions for the optimal manufacturing process of lotion were 61.93℃ in mixing temperature and 15.85 min in mixing time. Predicted values at the mixing temperature (60℃) and mixing time (20 min) were 100.69% of assay, 5.57 of pH, and 98.07% of weight variation. In the verification of the actual measurement the obtained values showed 100.29±0.98% of assay, 5.57±0.02 of pH, and 98.27±0.89% of weight variation, respectively, in good agreement with predicted values.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.992-997
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• 2002

Two in vivo experiments were conducted to evaluate the effect of novel urease inhibitor hydroquinone (HQ) on ammonia release rate from urea hydrolysis, nitrogen balance, nutrient digestibility and efficiency of microbial protein synthesis. In Exp. 1, twelve crossbred cannulated lambs were randomly assigned within initial body weight block to one of four HQ treatments, which included 0 (control), 30, 60 or 80 mg HQ/kg DM intake. Ammonia concentration and pH of ruminal fluid were immediately measured at 0, 2, 4, 6 and 8 h after feeding. Increasing the dose of HQ tended (p<0.15) to linearly decrease NH3 formation. The ammonia peak concentration (2 h post-feeding) in animals receiving HQ was approximately one-half of that in animals not receiving HQ (p<0.01), and a relatively sustained ammonia release could be obtained at the dose of 30 or 60 mg HQ/kg DM. In Exp. 2, sixteen intact crossbred lambs (weight $40{\pm}0.8kg$) were used in a $2{\times}2$ factorial design experiment. The four rations consisting of soybean meal-based (SBM) or urea-based (Urea) nitrogen source with or without HQ (S1, S0, U1 and U0) were fed in digestion and N balance trials. Apparent digestibility of major nutrients except that of ADF was not affected by either nitrogen source or addition of HQ. Regardless of nitrogen source, supplementation of HQ significantly improved ADF digestibility (p<0.05). The various ration had no effects on N metabolism in the presence of HQ. There was significant difference between total purine derivatives (PD), estimated efficiency of microbial N synthesis (p<0.05) and urea-N excretion (p<0.01) in the urine for the SBM ration and for the Urea ration. However, HQ had little influence on efficiency of microbial N synthesis as proportion of daily intake of total tract digestible OM (p>0.05). No interactions between main nitrogen source and HQ were measured throughout the trial. Results of this study suggest that addition of HQ to ration may improve ADF digestion with having no negative effect on N metabolism and microbial protein production.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.2
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• pp.53-61
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• 1999

This study was conducted to determine the optimal collecting time and methods of utilization of forest topsoil as a seed-bank source for revegetation materials of slopes. From April to November of 1998, nursery seedbeds in the greenhouse of Seoul National University were seeded with mixtures of forest topsoil and seeds. The nursery seedbeds were treated to evaluate the effect of depths of forest topsoil and seeding amounts. Seasonal experiments with $3{\times}3$ factorial design were conducted in April, June and August. More than 40 seedlings/$m^2$ were observed as the naturally-emerged species in the plot, treated with the top-layer forest soil within the depth of 10cm. However, it was found, as seeding more seeds, the number of appearance of the naturally-emerged species reduced because of the heavy competition between the seeded and the naturally-emerged. According to the results of this research, it is recommended that seeding amount should be no more than 1,000 seeds/$m^2$ to avoid the severe competition. Also it was observed that the forest topsoil collected in spring(April) is better than that collected in summer. The more species of the naturally-emerged were found in the forest topsoil collected in spring. Forest-topsoil-mixed-materials as a seed-bank source could significantly increase the plant diversity and productivity. Effective use of forest topsoil as a seed-bank source may become a valuable tool in future restoration of disturbed slopes for promoting plant community diversity and recycling of spoiled-soils from the slopes.