• 한국기계가공학회지
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• 제19권4호
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• pp.71-78
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• 2020

The rotary feed axes of a 5-axis machine tool can increase the freedom of the tool posture, while reducing feed speed and rigidity. In addition, as a ball-end mill is inevitably used during machining by rotational feed, the step-over length is reduced compared to the flat-end mill, thereby reducing the material removal rate. Therefore, this study attempts to improve the material removal rate, feed speed, and machining stability using the corner radius flat-end mill and a fixed controlled machining method for the rotary feed axes during roughing. In addition, the tapered ball-end mill and simultaneously controlled machining method for the rotary feed axes were used for finishing to improve the propeller's 5-axis machining efficiency by enhancing the surface quality. In order to create the tool path effectively and easily, we propose a specific approach for using the propeller's geometric properties and evaluate the effectiveness of the proposed method by comparing it with the method of the dedicated module.

• 한국초지조사료학회지
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• 제39권3호
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• pp.185-188
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• 2019

The production of traditional cool season grasses in temperate regions is becoming hampered during summer seasons due to water deficit. Thus, incorporating water use efficient warm season annual grasses are generally considered to fill the gap of summer season forage reduction that would offer considerable flexibility and adaptability to respond to forage demand. Teff (Eragrostis teff Zuccagni) Trotter) is, a C4 drought tolerant warm season annual grass primarily grown for grain production, recently gaining interest for forage production particularly during summer season. Previous reports have showed that teff is palatable and has comparable forage biomass and feed quality as compared to other warm season annual grasses which would make it an alternative forage. However, the available data are not comprehensive to explore the potential of teff as forage, hence further assessment of genotype variability and performance along with compatibility study of teff with forage production system of specific environment is key for future utilization.

• Asian-Australasian Journal of Animal Sciences
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• 제29권10호
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• pp.1458-1463
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• 2016

A 42-d study with 384 Hy-line brown laying hens was conducted to assess the effects of dietary octacosanol supplementation on laying performance, egg quality and blood metabolites of laying hens. Hens were randomly allocated into 4 dietary groups of 8 cages each, which were fed basal diet supplemented with 0 (Control), 9 (OCT9), 18 (OCT18), and 27 (OCT27) mg/kg diet of octacosanol isolated from rice bran, respectively. The experiment was conducted in an environmental controlled house and hens were fed twice daily for ad libitum intake. Laying performance was determined over the 42-d period, and egg quality as well as blood metabolites were estimated on d 21 and d 42. Diets in OCT18 and OCT27 increased (p<0.05) laying rate, egg weight, egg mass, egg albumen height, Haugh unit and eggshell strength on d 42, but decreased (p<0.05) feed conversion rate and levels of total cholesterol, triglyceride and low density lipoprotein cholesterol in the serum as compared to those of Control. Feed intake, yolk color, yolk diameter, eggshell thickness and high density lipoprotein cholesterol were similar (p>0.05) among treatments. Results demonstrate that supplementing 18 to 27 mg/kg diet of rice bran octacosanol can improve laying rate and egg quality and reduce blood lipid of laying hens.

• 한국응용과학기술학회지
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• 제22권1호
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• pp.62-70
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• 2005

Step-feed process for biological nitrogen removal were analyzed numerically for the each unit and final total nitrogen(TN) effluent by water quality management(WQM) model and the results were compared data from these wastewater treatment plants. No bugs and logic error were occurred during simulation work. All of the simulation results tried to two times were obtained and both results were almost same as this model has become good reappearance. It was concluded that most of nitrogen removal occurred in the first oxic tank. Thus the controlling of the first anoxic tank may be more important in term of nitrogen removal. Also each unit of simulation result was kept good relationship with that of measured data. Accordingly this WQM model has good reliance. Finally, WQM model can predict final TN effluent within ${\pm}6.0mg/{\ell}$.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 추계학술대회 논문집
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• pp.251-254
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• 2005

The flow forming has been used to produce long thin walled tube parts, with reduced forming load and enhanced mechanical and surface quality for a good finished part compared with other method formed parts. So flow forming technique is used widely in industrial production. Especially spinning and flow farming techniques an used frequently in automotive, aerial, defense industry. In this paper, FEM analysis of three-roller backward flow forming of a workpiece is carried out to study effects of forming depth and feed rate on forming force. The axial and radial forces on several forming depth and feed rate conditions are obtained. The phenomena such as bell mouth, build up and bulging during simulation are observed as well.

• Asian-Australasian Journal of Animal Sciences
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• 제22권12호
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• pp.1661-1666
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• 2009

The objective of this study was to determine the effect of Se-enriched bean sprout, Se-enriched yeast and sodium selenite on productivity, egg quality and egg Se concentrations in laying hens. Using a Completely Randomized Design, 144 Rohman laying hens at 71 weeks of age were divided into four groups. Each group consisted of four replicates and each replicate contained nine hens. The dietary treatments were T1: control diet, T2: control diet plus 0.3 mg Se/kg from sodium selenite, T3: control diet plus 0.3 mg Se/kg from Se-enriched yeast, T4: control diet plus 0.3 mg Se/kg from Se-enriched bean sprout. The results showed that there was no significant difference (p>0.05) in feed intake, egg production and egg quality among treatments. Selenium supplementation from Seenriched yeast and Se-enriched bean sprout markedly increased (p<0.05) egg Se concentration as compared to the control and sodium selenite groups. The results indicated that Se-enriched bean sprout could be used as an alternative Se source in diets of laying hens.

• Asian-Australasian Journal of Animal Sciences
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• 제19권11호
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• pp.1643-1648
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• 2006

To investigate the effects of feeding restricted on growth, carcass characteristics and plasma profiles in an attempt for optimum responses, a total of 108 cross-bred finishing barrows [(Landrace${\times}$Yorkshire)${\times}$Duroc]weighing an average of $46.88{\pm}0.52kg$ were assigned in a randomized complete block (RCB) design to one of four treatments with three replicates and nine pigs per pen. Feeding regimens were, 1) ad libitum from 50 kg to market weight (Ad 3/3), 2) restricted feeding from 90 kg to market weight (Ad 2/3), 3) restricted feeding from 70 kg to market weight (Ad 1/3), and 4) restricted feeding from 50 kg to market weight (Ad 0/3). During the experimental period, average daily feed intake (ADFI) was decreased from 2.53 kg (AD 3/3) to 2.09 kg (AD 0/3) with increasing restricted feeding duration of (p<0.05). Average daily gain (ADG) of AD 3/3 (0.79 kg) was significantly higher (p<0.05) than those of AD 1/3 (0.74 kg) or AD 0/3 (0.72 kg). Feed efficiency was not influenced by restriction regimens. Blood IGF-I concentrations were increased from 74.14 to 134.25 (167.36-115.66) ng/ml as body weight increased. Blood leptin concentrations were affected by feed intake level and coincided with blood IGF-I concentrations. Most of carcass characteristics were not significantly affected by restricted feeding, however cooking losses in AD 1/3 and Ad 0/3 treatment diet were higher than those in Ad 3/3 and Ad 2/3. In addition, there was a trend that backfat thickness was lowered in proportional to decreasing feed intake (p>0.05). In conclusion, restricted feeding improved feed efficiency after 50 kg body weight without deteriorating the pork quality of barrows.

• 한국가금학회지
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• 제27권1호
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• pp.7-12
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• 2000

An experiment was conducted to investigate the effects of feeding fermented food waste on the egg production and egg qualities in laying hens. A lot of 30 commercial layer(ISA Brown) at the age 58 weeks were placed in individual of 80% commercial feed and 20% fermented food waste(C80%+F20%), a mixture of 50% commercial feed and 50% fermented food waste (C50%+F50%), and a mixture of 20% commercial feed and 80% fermented food waste (C20%+F80%). Daily measurements were made on feed intake, egg production rate, egg weight, yolk color, Haugh unit, shell color during the experimental period. At the end of the experiment, body weight change and egg cholesterol contents were determined. The results indicate that up to 50% of basal diet could be supplied by fermented food waste with little depression in feed intake and efficiency in egg production (p＜0.01). Egg weight, egg shell thickness and Haugh units were not significant different between the treatments and the control. Egg color quality improved with increasing the proportion of the fermented food waste in the diet.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2002년도 학술대회지
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• pp.482-485
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• 2002

200만호 주택건설로 폭발된 1980년대 주택건설 시장의 활성화는 수도권 및 신도시를 중심으로 많은 APT를 양산하였고 그 과정에서 품질수준은 물량 공급 위주의 주택정책으로 소비자의 욕구를 충족시키지 못하였고 준공된 건물에서는 예상치 못한 많은 하자를 발생시켰다. 이에 따라 $1980\~1990$년대 공동주택의 하자 예방을 위한 연구가 수행되어 하자 다발 공종과 분야별 빈도 및 하자 발생으로 인한 손실추정 등 여러 연구 성과가 축적되었으나 하자 발생율을 줄이고 하자로 인한 소비자의 불만족을 해소시키는데는 크게 기여하지 못하고 있다. 이는 하자 관련 연구가 실제 공사를 수행하는 시점에 적절히 관리하고 통제하는 SYSTEM과 연계되지 못하고, 제대로 적용되지 못하기 때문이다. 따라서 본 연구에서는 국내 건설공사 중에서 공통주택에서 발생하는 하자에 관한 정보와 현황에 대한 분석을 실시하고, 그 유형별 특성에 따른 분류를 실시한 뒤 이를 종합하여 체계적인 정보의 확보 및 활용을 위한 WEB 기반 FEED-BACK 시스템을 제안하고자 한다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권10호
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• pp.1435-1440
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• 2008

An experiment was carried out to investigate whether a local breed of cattle is better adapted than European breed crosses to low quality feeds and to variations in their supply. Four Red Chittagong (RC) and four Holstein cross Sahiwal (Hx) cattle were used to compare the intake and digestibility of German grass (Echinocloa crusgalli) and rice straw with four regimes of feed supply. These were; a choice of German grass and rice straw each offered ad libitum on the same day (A); German grass and rice straw offered ad libitum on alternate days (B); rice straw offered ad libitum for 5 days followed by German grass ad libitum for 5 days (C); and German grass offered ad libitum for 5 days followed by rice straw ad libitum for 5 days (D). Each breed was offered the treatments in a $4{\times}4$ Latin Square design. The German grass intake and total dry matter intake per kg metabolic live weight were significantly higher for the Hx than for RC, but there were no significant effects of genotype on digestibility of nutrients or live weight. Treatment A had the highest proportion of German grass relative to rice straw in the total DM intake, and had the highest total DM intake and apparent digestibility of nutrients compared with treatments B, C and D. It was concluded that there was no significant evidence that the RG cattle were better adapted to a variable supply of low quality feed than Hx cattle, and that the variable feed supply reduced the ability of cattle to select a preferred diet and consequently nutrient intake was depressed.