• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.1004-1007
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• 2005

As a new approach to analyze grinding energy, this paper introduces a specific grinding energy model based on the average grain. Using this model, grinding characteristics such as specific grinding energy of SM45C were investigated with changing variables such as grain size of CBN, workpiece velocity(v) and apparent depth of cut(Z) in down-surface grinding. From the experimental results, the specific grinding energy decreases as the maximum undeformed chip thickness increases.

• Journal of Animal Science and Technology
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• 제62권3호
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• pp.374-384
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• 2020

Two experiments were conducted to determine apparent metabolizable energy (AME), nitrogen-corrected AME (AMEn), and ileal digestible amino acid (AA) content of brown rice (BR) and to investigate the effect of dietary supplementation of BR on laying performance and egg quality of laying hens. In Exp. 1, 72 Hy-line Brown layers (49-week-old) were allocated to two treatments using a completely randomized block design, and each treatment included six cages per treatment and six hens per cage. A semi-purified diet was formulated to include BR as the sole source of AA and energy and an N-free diet was used to determine basal endogenous loss of AA. The hens were fed a commercial layer diet for adaptation to the experimental environment and diet for 7 days from d 0, and then fed experimental diets for 5 days from d 7. Excreta were collected from d 10 to 11 and ileal digesta were collected on d 12. On a dry matter (DM) basis, the AME and AMEn of BR was determined at 3,773 and 3,729 kcal/kg, respectively. The apparent ileal digestibility (AID) of BR ranged from 32.7% for Thr to 73.7% for Arg. The range of the standardized ileal digestibility (SID) value was between 79.4% for Met and 96.6% for Lys. In Exp. 2, 252 Hy-line Brown layers (44-week-old) were divided into four groups, comprising seven replicates of nine birds each and assigned to four experimental diets containing 0 (Control), 5%, 10%, or 15% BR for 5 weeks. The BR-containing diets were formulated to be equal in the content of AMEn and digestible AA to those of the diet without BR. No significant differences were observed in laying performances. Egg quality and blood profiles were not linearly or quadratically affected by dietary treatments. These results suggest that up to 15% BR can be included into layer feed without any adverse effects on laying performance and egg quality, if its energy and digestible AA values are well evaluated.

• 자원리싸이클링
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• 제10권3호
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• pp.60-65
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• 2001

폴리염화비닐(PVC)을 0~2 M NaOH수용액중에서 반응온도 $200~250^{\circ}C$, 반응시간 0~5시간으로 수열처리한 경우 PVC의 탈염화수소속도에 관해서 조사했다 수중에서는 PVC분말의 탈염화수소반응은 외견상 0차반응으로 진행되며, 이때의 활성화에너지는 약 46 kcal/mol이다. NaOH중에서의 탈염화수소에서는 NaOH농도가 0.5 M까지는 탈염화수소반응은 촉진되어지며 탈염화수소반응은 외 견상 1차반응으로 진행되었다. 또한 0.5M이상에서는 반응속도는 거의 일정했다. 0.1 M 및 0.5M NaOH수용액중에서의 탈염화수소반응의 활성화에너지는 약 46 kcal/mol로서 수중의 경우와 거의 같았다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1155-1162
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• 2015

This study aimed to evaluate the nutrient digestibility of growing rabbits fed diets with different levels of either Leucaena leucocephala (LLM) or Moringa oleifera (MOLM) leaf meals and also to compare total collection and $TiO_2$ marker methods for estimating digestibility. A total of 30 California growing rabbits ($1.81{\pm}0.19kg$ live weight on average) were randomly distributed into five experimental groups of six rabbits each and were housed in individual cages. The groups were control, 30% LLM, 40% LLM, 30% MOLM, and 40% MOLM. All groups received pelleted diets for two weeks; diets also contained 4 g/kg titanium dioxide as dietary marker. Daily feed intake was recorded during the whole experimental period and total feces were collected daily and weighed individually during four days. The results showed that there were no difference (p>0.05) in feed, dry matter (DM), organic matter (OM), crude protein (CP), digestible energy, and crude fiber (CF) intake between the control group and the other experimental groups. The apparent digestibility values of DM, OM, CP, CF, acid detergent fiber, and gross energy were the highest for control group (p = 0.001), meanwhile MOLM diets had generally higher nutrient digestibility coefficients than LLM diets. Increasing the inclusion level of leaf meal in the diet from 30% to 40% improved the digestibility of CF from 45.02% to 51.69% for LLM and from 48.11% to 55.89% for MOLM. Similar results for apparent nutrient digestibility coefficients were obtained when either total collection or indigestible marker method was used. In conclusion, the digestibility of MOLM containing diets were better than LLM diets, furthermore $TiO_2$ as an external marker could be used as a simple, practical and reliable method to estimate nutrients digestibility in rabbit diets.

• Animal Bioscience
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• 제35권4호
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• pp.577-586
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• 2022

Objective: The objective of this study was to evaluate the effects of supplementing quercetin extracted from Sophora japonica flower (QS) to the diet of broiler chicks on their growth performance, apparent nutrient digestibility, cecal microbiota, serum lipid profiles, relative organ weight, and breast muscle quality. Methods: A total of 1,088 1-day-old broiler chicks (mixed sex) were randomly assigned to four groups based on the initial body weight (43.00±0.29 g). The experimental period was 35 days (starter, days 0 to 7; grower, days 7 to 21; finisher, days 21 to 35). There were 17 replicate cages per treatment and 16 birds per cage. Dietary treatments consisted of birds receiving basal diet without quercetin as the control group and treatment groups consisted of birds fed basal diet supplemented with 0.2, 0.4, or 0.6 g/kg QS. Results: With the increase of the QS dosage, body weight gain during days 0 to 7 (p = 0.021), 7 to 21 (p = 0.010), and 1 to 35 (p = 0.045), feed intake during days 0 to 7 (p = 0.037) and 1 to 35 (p = 0.025), apparent dry matter digestibility (p = 0.008), apparent energy retention (p = 0.004), cecal lactic acid bacteria counts (p = 0.023), the relative weight of breast muscle (p = 0.014), pH value from breast muscle (p<0.001), and the water holding capacity of breast muscle (p = 0.012) increased linearly, whereas the drip loss from breast muscle (p = 0.001) decreased linearly. Conclusion: The addition of QS in the diet of broiler chicks had positive effects on the breast muscle yield and breast muscle quality, and improved the dry matter digestibility and energy retention by increasing cecal beneficial bacteria counts, thus improving growth performance.

• Animal Bioscience
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• 제36권11호
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• pp.1700-1708
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• 2023

Objective: The objective of this study was to determine the effects of β-mannanase on metabolizable energy (ME) and apparent total tract digestibility (ATTD) of protein in various feedstuffs including barley, copra meal, corn, corn distillers dried grains with solubles (DDGS), palm kernel meal, sorghum, and soybean meal. Methods: A basal diet was formulated with 94.8% corn and 0.77% amino acids, minerals, and vitamins and test diets replacing corn-basal diets with barley, corn DDGS, sorghum, soybean meal, or wheat (50%, respectively) and copra meal or palm kernel meal (30%, respectively). The basal diet and test diets were evaluated by using triplicated or quadruplicated 2×2 Latin square designs consisting of 2 diets and 2 periods with a total of 54 barrows at 20.6±0.6 kg (9 wk of age). Dietary treatments were levels of β-mannanase supplementation (0 or 800 U/kg of feed). Fecal and urine samples were collected for 4 d following a 4-d adaptation period. The ME and ATTD of crude protein (CP) in feedstuffs were calculated by a difference procedure. Data were analyzed using Proc general linear model of SAS. Results: Supplementation of β-mannanase improved (p<0.05) ME of barley (10.4%), palm kernel meal (12.4%), sorghum (6.0%), and soybean meal (2.9%) fed to growing pigs. Supplementation of β-mannanase increased (p<0.05) ATTD of CP in palm kernel meal (8.8%) and tended to increase (p = 0.061) ATTD of CP in copra meal (18.0%) fed to growing pigs. Conclusion: This study indicates that various factors such as the structure and the amount of β-mannans, water binding capacity, and the level of resistant starch vary among feedstuffs and the efficacy of supplemental β-mannanase may be influenced by these factors.

• 한국식품과학회지
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• 제20권5호
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• pp.711-717
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• 1988

배추의 염절임중 배추 조직으로의 소금흡수 속도를 측정하고 확산에 관한 수학적인 모델과 computer simulation을 통해서 확산계수를 구하였다. 배추 줄기로의 소금의 침투 및 탈염 될 때의 확산계수는 각각 $1.7{\times}10^{-11}m^2/s$와 $11.6{\times}10^{-11}m^2/s$이었다. Apparent diffusivity는 소금의 농도와 배추의 종류에 커다란 영향을 받지 않으며, 온도의존성은 Arrhenius식으로 나타낼 수 있고 이때의 활성화 에너지는 66 KJ/mol 이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권9호
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• pp.1355-1359
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• 2003

This study examined the replacement of the fish meal (FM) with commercial poultry by-product meal (PBM) in practical diets for rainbow trout (Onchorynchus mykiss, Walbaum). Five isocaloric and isonitrogenous diets containing levels 0 (control), 10, 20, 30 and 40% of PBM as a replacement for FM were fed to three replicate groups of rainbow trout with a initial weight $34.50{\pm}0.43g$ (mean${\pm}$SE). Protein efficiency ratio (PER) of diets containing PBM up to 20% were similar to the control while significantly lower values were obtained from the groups receiving higher levels of PBM (p<0.05). Apparent protein digestibility coefficients (ADCs) were significantly lower than that of the control group when PBM was included at level of 20% or more. Similarly, significantly lower values were observed with diets containing 30 and 40% PBM in terms of dry matter, organic matter, ether extract, ash and energy digestibility (p<0.05). Dietary treatments did not significantly affect the body composition of the fish in terms of dry matter, crude protein, ether extract and ash. In conclusion, PBM in a proportion of 20% may replace about 40 % of FM in rainbow trout diet without significant impairment grow.

• Asian-Australasian Journal of Animal Sciences
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• 제13권7호
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• pp.948-956
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• 2000

The effect of high and low level of feed intakes on nutrient digestibility, nutrient losses through methane, energy and protein utilization by goats fed on alfalfa (Medicago sativa L.) pellets based diets was investigated in this study. Twelve castrated Japanese goats were employed in two subsequent digestion and metabolism trials. The goats were divided into three groups, offered three diets. Diet 1 consisted of 100% alfalfa pellet, Diet 2 was 70% alfalfa pellet and 30% corn, and Diet 3 was 40% alfalfa pellet and 60% corn. The two intake levels were high (1.6 times) and low (0.9 times) the maintenance requirement of total digestible nutrients (TON). Rumen ammonia nitrogen ($NH_3$-N) level of Diet 1 was lower (p<0.001) compared to Diets 2 and 3, but the values were always above the critical level (I50 mg/liter), The pH values of rumen liquor ranged from 6.02 to 7.30. Apparent digestibility of nutrient components did not show differences (p>0.05) between the two intake levels but inclusion of corn significantly altered the nutrient digestibility. Diet 3 had highest (p<0.001) dry matter (DM), organic matter (OM), ether extract (EE) and nitrogen fee extract (NFE) digestibility followed by the Diet 2 and Diet 1. The crude protein (CP) digestibility values among the three diets were in a narrow range (70.1 to 70.8%). Crude fiber (CF) digestibility for Diet 3 was slight higher (p>0.05) than that for other two diets. When alfalfa was replaced by corn, there were highly significant (p<0.001) increases in DM, OM, EE and NFE apparent digestibility and a slight increase in the CF digestibility (p>0.05). There were no differences (p>0.05) in energy losses as methane ($CH_4$) and heat production among the diets but energy loss through urine was higher for the Diet 1. The total energy loss as $CH_4$ and heat production were higher for the high intake level but the energy loss as $CH_4$ per gram DM intake were same (0.305 kcal/g) between the high and low intake level. Retained energy (RE) was higher for Diet 3 and Diet 2. Nitrogen (N) losses through feces and urine were higher (p<0.001) for Diet 1. Consequently, N retention was lower (p>0.05) for Diet 1 and higher in Diets 3 and 2. It is concluded that inclusion of corn with alfalfa increased the metabolizable energy (ME) and RE, and retained N through reducing the energy and N losses. The high level of intake reduced the rate of nutrient losses through feces and urine.

• 한국건설순환자원학회논문집
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• 제7권4호
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• pp.121-127
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• 2012

본 연구에서는 플라이애시를 치환한 시멘트 모르터의 양생온도에 따른 강도증진을 검토하기 위하여 등가재령방법에 의한 강도증진해석을 실시하였다. 플라이애시를 30% 치환한 시멘트모르터의 겉보기활성화에너지를 ASTM C 1074 방법에 의하여 산정한 결과 34.75KJ/mol로 산정되었고, 이를 토대로 Plowman 모델과 Gompertz 모델을 이용하여 해석한 결과 해석치가 측정치를 양호하게 추정함을 알 수 있었고 특히 Gompertz 모델식이 보다 양호한 추정 정밀도를 갖는 것으로 확인되었다.