• Asian-Australasian Journal of Animal Sciences
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• 제22권12호
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• pp.1620-1624
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• 2009

This study aimed to clarify the effect of mobile bag size and ratio of sample size to bag surface area on intestinal digestibility of forage in sheep. Four Suffolk ewes fitted with ruminal and proximal duodenal cannulae were fed second-cut Italian ryegrass (Lolium multiflorum Lam.) hay twice daily, and the same forage was used to measure intestinal digestibility. The forage samples were incubated in the rumen for 16 h and then in pepsin-HCl solution for 3 h before intestinal incubation. The incubated forage samples were placed in a nylon mobile bag. The bag sizes used were either 20 mm${\times}$20 mm (small bag size; SBS) or 30 mm${\times}$30 mm (large bag size; LBS) and the ratio of the sample size to the surface area of the bag was either 5.5 $mg/cm^{2}$ (low ratio; LR) or 11.0 $mg/cm^{2}$ (high ratio; HR) resulting in four different treatment conditions: SBS-LR, SBS-HR, LBS-LR and LBS-HR. Eight bags per animal were inserted through the duodenal cannulae at 15-min intervals and were subsequently collected from the feces of the animal. The mean intestinal bag transition time did not differ significantly between animals, but ranged from 23.2 to 27.0 h. The intestinal digestibility of dry matter (IDDM) ranged from 0.162${\pm}$0.019 g/g in the SBS-HR treatment group to 0.195${\pm}$0.018 g/g in the SBS-LR treatment. The intestinal digestibility of crude protein (IDCP) ranged from 0.610${\pm}$0.031 g/g in the LBS-LR treatment to 0.693${\pm}$0.018 g/g in the SBS-LR treatment. There was no difference in the IDDM and IDCP between different treatments. It was therefore concluded that the size of the mobile bag and the ratio of the sample size to the bag surface area did not influence the intestinal digestibility of forage. Future studies should use bags with high ratios of sample size to surface area in order to obtain sufficient residue for further analysis.

• Asian-Australasian Journal of Animal Sciences
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• 제22권9호
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• pp.1256-1266
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• 2009

Effects of particle size and physical effective fibre (peNDF) of rice straw in diets on chewing activities, feed intake, flow, site and extent of digestion and rumen fermentation in goats were investigated. A 4${\times}$4 Latin square design was employed using 4 mature Liuyang black goats fitted with permanent ruminal, duodenal, and terminal ileal fistulae. During each of the 4 periods, goats were offered 1 of 4 diets that were similar in nutritional content but varied in particle sizes and peNDF through alteration of the theoretical cut length of rice straw (10, 20, 40, and 80 mm, respectively). Dietary peNDF contents were determined using a sieve for particle separation above 8 mm, and were 17.4, 20.9, 22.5 and 25.4%, respectively. Results showed that increasing the particle size and peNDF significantly (p<0.05) increased the time spent on rumination and chewing activities, duodenal starch digestibility and ruminal pH, and decreased ruminal starch digestibility and $NH_{3}$-N concentration. Intake and total tract digestibility of nutrients (i.e. dry matter, organic matter, and starch) and ruminal fermentation were not affected by the dietary particle size and peNDF. Increased particle size and peNDF did not affect ruminal fibre digestibility, but had a great impact on the intestinal and total tract fibre digestibility. The study suggested that rice straw particle size or dietary peNDF was the important influential factor for chewing activity, intestinal fibre and starch digestibility, and ruminal pH, but had minimal impact on feed intake, duodenal and ileal flow, ruminal and total tract digestibility, and ruminal fermentation.

• 한국환경생태학회지
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• 제32권5호
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• pp.507-512
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• 2018

곰솔의 줄기밀도, 현존량 확장계수, 상대생장식 및 임분 현존량을 파악하기 위하여 전라남도 여수지역에 위치하고 있는 15년생, 29년생, 45년생 등 3개 곰솔 천연임분을 대상으로 임분별 5주씩 총 15주의 표본목을 선정 벌목하여 조사하였다. 줄기밀도는 $0.440-0.457g/cm^3$이었으며, 임분간 유의적인 차이는 없었다. 지상부와 뿌리를 포함한 임목 전체의 현존량 확장계수는 모두 임령이 증가할수록 감소하였으며, 임분 1은 지상부 현존량 확장계수에서 임분 2, 3과 유의적인 차이가 있었고, 임목 전체 현존량 확장계수에서 임분 3과 유의적인 차이가 있었다. 이것은 임령이 증가할수록 줄기의 건중량 구성비가 높아지기 때문이며, 임분 1의 경우 유령림의 생장특성을 보이기 때문으로 판단되었다. 흉고직경(D) 또는 흉고직경과 수고($D^2H$)를 독립변수로 하고 부위별 건중량(Wt)을 종속변수로 하는 2개 유형의 상대생장식($Wt=aD^b$, $Wt=a(D^2H)^b$)을 유도하고 적합도를 검정하였다. 임분 1, 2, 3의 지상부 현존량은 각각 50.72t/ha, 89.92t/ha, 194.07t/ha이었으며, 뿌리를 포함한 임목 전체 현존량은 각각 61.62t/ha, 113.12t/ha, 248.36t/ha이었다.

• 한국초지조사료학회지
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• 제12권1호
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• pp.33-40
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• 1992

본 시험은 수단그라스계 잡종의 수량, 그루터기의 저장탄수화물 및 주수저하에 미치는 파종량과 질소시비수준의 영향을 구명하기 위하여 1983년 서울대학교 농과대학 부속실험목장의 사초시험포장에서 실시되었으며 얻어진 결과를 요약하면 다음과 같다. 1.파종량은 사초수량에 미치지 못하였으나 질소시비수준에 의한 사초수량의 차이는 고도의 유의성이 인정되었다.높은 질소시비 수준에서 최대 건물수량이 생산되었다.2.1회 예취시 파종량과 질소시비수준은 공히 저장탄수화물 수준에 영향을 주었다(P<.0.5).2회 예취시는 2처리 공히 저장탄수화물 수준에 영향을 미치지 못하였다.3.1회 예취시 파종량만이 주수저하에 영향을 주었다.그러나 총고사율은 파종량과 질소시비순에 의해 영향을 받았다(P<.0.5).높은 파종량은 그루터기의 높은 고사율을 유발하였다.4.본 시험결과에 의하면 수단그라스계 잡종을 여름철 사초로 이용할 경우 최대수량을 얻기 위해 ha당 40kg의 파종량과 300kg의 질소시용이 가장 바람직하다고 생각된다.

• 한국초지조사료학회지
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• 제5권1호
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• pp.84-89
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• 1985

1. Alfalfa의 조단백질(粗蛋白質)은 채취시기가 경과함에 따라 1회(回) 19.64%에서 4회(回) 12.37%로 낮아졌으며, 조섬유, CWC, Cellulose도 낮아지는 경향을 보였다. Orchard grass도 조단백질(粗蛋白質)은 1회(回) 13.79%에서 2,3회(回) 12.97, 12.85%로 낮아졌으며 4회(回) 14.72%로 다소 상승하였다. 그밖에 조섬유, CWC는 채취시기가 진행됨에 따라 낮아졌으며 Cellulose는 시기에 다소 증가하였으나 그후 감소하였다. 2. Alfalfa와 Orchard grass의 DM과 Cellulose 소화율(消化率) Alfalfa의 채취시기별 DM 소화율은 1, 2, 3회(回) 51.80, 51.86, 52.92%로 별반 차이가 없었으나 4회(回) 59.52%로 가장 높았고 점차적으로 채취시기가 경과함으로써 증가하는 경향을 보였다. Cellulose 소화율은 3회(回) 시기에 감소하였다가 4회(回)에 약간 상승하였다. Orchard grass의 DM소화율은 1,2,3,4회(回)에 62.21, 66.10, 60.95, 66.32%로 2회(回) 채취초기에 소화율이 높아졌고 3회(回)에 다소 감소하였다가 4회(回)에 증가하였다. Cellulose 소화율은 Alfalfa와 마찬가지로 3회(回) 시기에 감소하였다가 4회(回)에 약간 상승하였다. 3. Alfalfa와 Orchard grass의 발효율(醱酵率) 및 발효속도(醱酵速度) 측정(測定) Alfalfa의 채취시기별로 볼 때 DM의 시간당 발효율은 1회(回)가 0.83%로 가장 높았으며 3, 4회(回)는 별반 차이가 없었다. 또한 Cellulose의 발효율(醱酵率)도 1회(回) 시간당(時間當) 1.29%로 가장 높았고 2,3회(回)에 감소하였다가 4회(回)에 다소 증가하였다. Orchard grass의 DM 소화속도(消化速度)는 1회(回)에서 4회(回) 1.42, 1.58, 1.60, 1.57%로 2.3회(回) 채취시에 빠른 경향을 보였으며 Cellulose는 2회(回)에 1.77%로 가장 높았다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권9호
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• pp.1233-1242
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• 2011

The in vivo digestibility of mulberry leaves (Morus alba) and the effects of the partial replacement of cotton seed with fresh mulberry leaf in rations on the performance of growing Vietnamese cattle was investigated. For the in vivo digestibility trial, twenty castrated rams of Phanrang breed (a local prolific breed) with an initial weight of 23-25 kg, were first assigned to four groups according to weight and then randomly assigned to one of four dietary treatments to determine digestibility of nutrients in mulberry leaves (M. alba), natural Bermuda grass (Cynodon dactylon), elephant grass (Pennisetum purpureum) and buffalo grass (Panicum maximum cv. TD 58). All forages were cut and chopped daily before being offered (at 120% maintenance) to the sheep. In the feeding trial, 20 Laisind (Vietnam yellow cows${\times}$Red Sindhy bulls) crossbred bulls averaged 18 month old and 184 kg were used to investigate the effect of partial replacement of cottonseed in the diet by mulberry leaves on live weight gain and feed conversion rate. The experiment was a randomized complete block design with four levels of fresh mulberry leaves which varied from 0 to 15% of total dietary dry mater and five animals per treatment over an 84 day period. The in vivo digestion trial showed the superior quality of mulberry leaves compared with the grasses. Chemical analysis indicated that mulberry leaves had the highest CP and the lowest NDF contents (22.3 and 31.1% DM, respectively) among the four forages tested. Digestibility of DM and OM of the mulberry leaf (66.4 and 71.8%, respectively) was also the highest but that of CP (58.2%) and NDF (58.4%) was the lowest of the four forages evaluated (p<0.05). Consequently, the ME value and therefore net energy (NE) and unit feed for lactation (UFL) values of the mulberry leaves, which was estimated from chemical composition and digestibility values, were the highest among the forages investigated in the present study. Results of the feeding trial showed no treatment effect on average daily gain (ADG) of the cattle. The values were 554, 583, 565 and 568 g/d for animals in the diets of 0, 5, 10, and 15% mulberry leaves inclusion, respectively. Total DM intake of the animal was not affected by the treatment when expressed as kg/animal/d. However, when adjusted for metabolic weight of the animal the DM intake was reduced (p<0.05) as whole cottonseed was replaced by mulberry leaves in the ration. When the level of mulberry leaves in the ration increased from 5 to 15% of dietary DM at the expense of whole cottonseed, CP and ME intakes of the cattle were significantly decreased (p<0.05) and the feed to gain ratio reduced by 8 to 14% as compared with the control diet (p<0.05). Mulberry leaf is a good feed ingredient for ruminants because of its high level of crude protein and high digestibility of nutrients and energy. Mulberry leaves can be efficiently used as a source of protein supplement to replace cottonseed, a more expensive animal feeds ingredient, in the diet for Vietnamese cattle.

• Asian-Australasian Journal of Animal Sciences
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• 제20권10호
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• pp.1525-1538
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• 2007

Because of the increasing evidence of potential benefits of conjugated linoleic acid (CLA) on human health, there is a need to investigate its status in commercial dairies and develop feeding strategies to enhance the content and supply of CLA in milk and milk products. A two-year experiment was conducted to study the status of milk fat c-9, t-11 CLA on four selected commercial dairy farms in Utah (two) and Idaho (two), USA. Farms A and C grazed cows on pasture and supplemented with 7.0 kg/cow per day of their respective grain mixes during summer, while conserved forage and grain mix was fed during winter. Farm B fed a total mixed diet all year, with 10% of diet dry matter as fresh cut pasture during summer. Farm D had 1/3 of its cows grazed on pasture and supplemented with a total mixed diet during summer, while the rest were fed a total mixed diet. All cows in Farm D were fed a total mixed diet during winter. Farms A, B, C, and D had on average 80, 400, 150, and 500 milking cows, respectively, with Holstein or its crosses as the major breed. On a year-round basis, Farms A and C produced milk with 60% or more milk fat c-9, t-11 CLA and transvaccenic acid (TVA) contents than Farm B. Similarly, Farm D produced 30% or more c-9, t-11 CLA and TVA in milk than Farm B. Milk fat content of CLA and TVA was 150-200% more during summer compared with winter. Individual cows varied from 0.16 to 2.22% in milk fat c-9, t-11 CLA contents and 89% of the cows had c-9, t-11 CLA contents between 0.3 and 1.0% of milk fat. Individual cow variation was larger on Farms A and C compared with Farm D, with least variation on Farm B. Variation was larger in summer than in winter. The bulk tank milk c-9, t-11 CLA content varied from 0.27 to 1.35% of milk fat. Cows on Farms A and C produced similar or higher amounts of milk fat c-9, t-11 CLA on a daily basis even though their milk yield was lowest among the dairies. Concentration and supplies of c-9, t-11 CLA and TVA were highest from June through September and lowest from February through April, which should be the months for targeting improvement in the content and supply of milk fat c-9, t-11 CLA and TVA.

• Steel and Composite Structures
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• 제34권5호
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• pp.681-698
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• 2020

The paper addresses contribution to the modeling and optimization of major machinability parameters (cutting force, surface roughness, and tool wear) in finish dry hard turning (FDHT) for machinability evaluation of hardened AISI grade die steel D₃ with PVD-TiN coated (Al₂O₃-TiCN) mixed ceramic tool insert. The turning trials are performed based on Taguchi's L₁₈ orthogonal array design of experiments for the development of regression model as well as adequate model prediction by considering tool approach angle, nose radius, cutting speed, feed rate, and depth of cut as major machining parameters. The models or correlations are developed by employing multiple regression analysis (MRA). In addition, statistical technique (response surface methodology) followed by computational approaches (genetic algorithm and particle swarm optimization) have been employed for multiple response optimization. Thereafter, the effectiveness of proposed three (RSM, GA, PSO) optimization techniques are evaluated by confirmation test and subsequently the best optimization results have been used for estimation of energy consumption which includes savings of carbon footprint towards green machining and for tool life estimation followed by cost analysis to justify the economic feasibility of PVD-TiN coated Al₂O₃+TiCN mixed ceramic tool in FDHT operation. Finally, estimation of energy savings, economic analysis, and sustainability assessment are performed by employing carbon footprint analysis, Gilbert approach, and Pugh matrix, respectively. Novelty aspects, the present work: (i) contributes to practical industrial application of finish hard turning for the shaft and die makers to select the optimum cutting conditions in a range of hardness of 45-60 HRC, (ii) demonstrates the replacement of expensive, time-consuming conventional cylindrical grinding process and proposes the alternative of costlier CBN tool by utilizing ceramic tool in hard turning processes considering technological, economical and ecological aspects, which are helpful and efficient from industrial point of view, (iii) provides environment friendliness, cleaner production for machining of hardened steels, (iv) helps to improve the desirable machinability characteristics, and (v) serves as a knowledge for the development of a common language for sustainable manufacturing in both research field and industrial practice.

• 대한한의학원전학회지
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• 제24권2호
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• pp.23-50
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• 2011

"LeiGongPaoZhiLun" is the first pharmaceutical book, and there are various opinion on when LeiXiao(雷斅), the author lived. From the aspect of several data, it is appropriate most that LeiXiao live in the period of Sui(隋) Dynasty, like SuSong(蘇頌) in the Sung Dynasty said, This book was not made at one time by one person. At the beginning, it was written by LeiXiao and the later generations enlarged to finish. The original of "LeiGongPaoZhiLun" disappeared already but a large amount of this book was quoted to "ZhengLeiBenCao(證類本草)" to be preserved. The contents of "LeiGongPaoZhiLun" are the first professional book about processing of medicinal, in which most of processing of medicinal that is generally used today, is included and some methods are unused. Besides, the regulations of this book are specific, the range is broad, and theoretical frame is established for the first time. This book has abundant contents, in which several processing of medicinal are written. There are 10 methods such as steaming(蒸法), boiling(煮法), baking(炮法), stir-frying(炒法), calcining(煅法), long time boiling(煉法), scorching(燒法), baking after wrapping(煨法), immersing(浸法), washing(洗法), flying(飛法), etc. How to remove some section that is not used for drug, how to separate according to medical use and region to be applied, how to smash, how to cut, how to dry, container for medicine, warning for making a prescription, time to make medicine and amount of medicine, how to distinguish superior and inferior and origin, how to make medicine partially, etc, are contained in this book. The contents of "LeiGongPaoZhiLun" can be mixture of processing of medicinal of medical scientists and taoists. In conclusion, however, the effect by the later medical generations of "LeiGongPaoZhiLun" was not great on processing of medicinal. It stemmed from the difference of processing of medicinal in this very taoistic book that realistic difficulties were disregarded by taoists for training and practical purpose, treatment that is the reason that later medical generations used processing of medicinal. Consequently, there is no great relation between the development of processing of medicinal in the Sung Dynasty and this book. "LeiGongYaoXingFu(雷公藥性賦)" that was abundant in medical market in Ming(明) and Qing(清) period has no relation with "LeiGongPaoZhiLun" is kind of a distribution-purposed book that was mnge in or after Ming Dynasty. However, since a book that is said to be written by 'LiGao(李杲)'PaoZhihis nof a dijust borrowed and focus on a brief summery, it is not desirable for beginners to learn medical knowledge. "LeiGongPaoZhiLun" is the first pharmaceutical book and is a model to show how a science in the history of the herb medicine generated and developed and how such a book is changed and modified to make a change of value.

• 콘크리트학회논문집
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• 제22권6호
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• pp.867-873
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• 2010

이 연구에서는 강섬유로 보강된 철근콘크리트에서의 부식 특성에 관한 실험적 연구를 수행하였다. 먼저 강섬유의 보강콘크리트의 수송특성, 즉 공극률, 흡수성, 투과성 및 염소이온 확산성에 관한 실험을 수행하여 철근부식과 의 관계를 비교 평가 하였다. 강섬유의 보강으로 인해 약간의 압축강도 증가와 함께, 흡수성, 투과성 및 확산성에 관한 실험 결과에서도 콘크리트 내부로의 유해물질의 침투저항성이 크게 증가하는 것으로 나타났다. 철근부식과의 관계에서는 예상된 결과와는 다르게 강섬유의 혼입이 철근부식을 가속화 시키는 경향이 나타났다. 염화나트륨 용액이 침투하는 노출면에서는 강섬유의 부식팽창으로 인한 표면박리현상이 관찰되었으며, 철근부위 절단면에서는 철근 주변에 강섬유의 부식이 국부적으로 관찰 되었다. 고온 및 고농도의 염화물 환경에서의 건습 싸이클링이 노출표면에 가까운 공극에서 지속적으로 염분결정체의 증가와 더불어 내부공극에서의 강섬유의 부식으로 증가된 압력이 표면 박리를 일으킨 것으로 보인다. 결과적으로는 노출면 부근에서의 미세균열을 증가가 물, 염화이온 및 산소의 침투를 보강근으로의 가속화를 진행 시킨 것으로 판단이 된다. 이 연구에서는 강섬유로 보강된 철근콘크리트에서 철근부식에 영향을 주는 명확한 메커니즘은 충분히 규명이 되지 않았으며, 보다 명확한 관계를 이해하기 위해서는 부식과정에서 강섬유의 잠재적인 부식팽창에 관한 보다 상세한 실험적 연구가 필요할 것으로 판단되어 진다.