• 유기물자원화
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• 제24권2호
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• pp.15-29
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• 2016

본 연구는 바이오가스화 처리 유 무에 따라 하수슬러지 처리방법별, 즉 소각, 탄화, 건조, 고형화 등에 대한 환경성 및 경제성 분석을 실시하였다. 혐기소화에 대한 B/C분석에 대하여, 하수처리장 시설규모 $270,000m^3/d$ (하수슬러지 처리규모 $1,150m^3/day$)에서 B/C가 1이 되었다. 함수율을 95 %일 경우, B/C 는 하수처리장 규모 $100000m^3/d$ (하수슬러지 처리규모 $400m^3/day$)에서 1이 되었다. 혐기소화 + 고형화가 가장 경제성이 있었으며, 다음으로는 혐기소화 +소각과 혐기소화 + 건조였으며, 혐기소화 + 탄화가 가장 경제성이 약한 것으로 분석되었다. 유기물 분해율을 45 % 까지 증대시킨 경우 혐기소화를 시키지 않는 경우보다 혐기소화를 하여 후처리를 하는 경우가 처리비용이 3,000 - 5,000 원/톤 감소하고, 다만, 고형화로 후처리 하는 경우는 처리비용이 2,000 - 3,000 원/톤 감소하는 것으로 분석되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권5호
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• pp.719-725
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• 2003

An experiment was conducted to study the requirement of calcium (Ca) and non-phytin phosphorus (NPP) in commercial broilers during starter phase. Seven hundred and twenty day-old Vencob male broiler chicks were randomly distributed into 144 stainless steel battery brooders, 5 birds in each. Four levels each of Ca (6, 7, 8, and 9 g/kg) and NPP (3, 3.5, 4, and 4.5 g/kg diet) were fed in a factorial design in a corn-soya basal diet. Levels of dicalcium phosphate and oyster shell grit were adjusted to obtain the desired levels of Ca and NPP. Each diet was fed ad libidum to chicks in 9 battery brooders from one d to 21 d of age. Body weight gain and feed intake were depressed (p<0.01) by increasing the dietary Ca level (8 and 9 g/kg) at lower levels of NPP (3 and 3.5 g/kg diet). The growth depression observed at lower NPP level was alleviated by reducing the Ca content to 6 g/kg diet. The tibia ash content and tibia breaking strength increased with increase in both Ca (>6 g/kg) and NPP (>3 g/kg) levels. The leg abnormality score decreased (p<0.01) with increase in NPP content in the diet at all levels of Ca tested. The serum Ca and inorganic P levels were increased with increase in the level of the respective mineral in the diet, but the serum concentration of Ca and P were inversely related to the level of NPP and Ca, respectively /kg diet. In general, the excretion of macro minerals (Ca, and P), and micro minerals {zinc (Zn), manganese (Mn), iron (Fe), and copper (Cu)} was significantly lower at lower levels of Ca and NPP tested (6 and 3 g/kg diet, respectively). The mineral excretion increased with increase in dietary Ca and NPP levels, more conspicuously at the disproportionate ratio of these minerals (>2:1, Ca and NPP). Similarly, the retention of Zn, Mn, and Fe in liver was significantly higher (p<0.01) at lower levels of Ca and NPP tested. Results from this study indicate that the commercial broilers do not require more than 3 g NPP and 6g Ca/kg diet during starter phase (up to 21 d of age) for optimum weight gain, feed efficiency and utilization of Ca, P, Zn, Mn, Fe and Cu. However, the requirements of these minerals for optimum bone mineralization were higher than the levels suggested above.

• Asian-Australasian Journal of Animal Sciences
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• 제7권4호
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• pp.537-546
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• 1994

This experiment was carried out to compare the effects of six different plant protein sources such as soybean meal, extruded full-fat soybean, canola meal, rapeseed meal, cottonseed meal and perilla meal as a sole protein source of diets on growth performance and amino acid bioavailabilities in growing-finishing pigs. A total of 54 pigs with average 25 kg of body weight were used as experimental subjects for a 65-d feeding trial. Digestion trial was carried out with seven ileal-cannulated pigs. The most rapid rate of weight gain was observed in pigs fed soybean meal and full-fat soybean, the moderate one in pigs fed canola meal and cottonseed meal and the least one in pigs fed rapeseed meal and perilla meal (p<0.005). Feed efficiency was better for groups fed soybean meal and full-fat soybean than other protein meals (p<0.05). The apparent ileal digestibilities of essential amino acids of soybean meal and full-fat soybean (82.5% and 81.6%) were significantly (p<0.05) higher than those of other protein sources (61.2 to 69.4%). Regardless of protein sources, the apparent ileal digestibility of arginine was highest, whereas that of histidine was lowest among essential amino acids. Proline had the lowest digestibility among non-essential amino acids. True amino acid digestibilities tended to be higher than apparent amino acid digestibilities. The differences between true and apparent ileal digestibilities were greater in canola meal, rapeseed meal or cottonseed meal than other protein sources. The differences was greatest in praline except for cottonseed meal. The fecal digestibility appeared to be higher than the ileal digestibility. The differences between fecal and ileal digestibilities were greater in canola meal, rapeseed meal, cottonseed meal and perilla meal than in soybean meal and full-fat soybean. In general, praline was the most disappeared amino acid in the hind gut, while the net synthesis of lysine in the large intestine was observed in all protein sources except perilla meal. It is appropriate that swine feeds should be formulated based on true ileal amino acid digestibility of protein sources for pig's normal growth.

• Asian-Australasian Journal of Animal Sciences
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• 제21권12호
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• pp.1745-1752
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• 2008

This study was conducted to compare the growth performance and carcass evaluation of Jeju native cattle (JNC) and its crossbreds (CBK = 25 JNC: 50 Charolais: 25 Brahman and BCBK = 62.5 JNC: 25 Charolais: 12.5 Brahman) fed for a short fattening period. Eight male calves each of JNC (80.$40{\pm}10$), CBK ($113.50{\pm}12.3$), and BCBK ($100.3{\pm}9.5$) were weaned at 4 month of age and were fed similar diets for 18 months of their age. All animals were fed a growing ration until 12 months of age and thereafter switched to a fattening ration for a period of 6 months. Final body weight (BW) and BW gain were significantly higher in CBK and BCBK compared with JNC. The CBK and BCBK gained 27.42% and 25.99% more BW, respectively, compared with JNC. The CBK and BCBK animals consumed significantly less DM than JNC to gain a unit of BW. Body weight gain, DM intake and feed conversion efficiency were similar between CBK and BCBK. Weight of hot and cold carcass, ribs, boneless meat and Longissimus dorsi muscle area were significantly different among JNC and its crossbreds. The heaviest carcass was observed in CBK followed by BCBK and JNC. Carcass, chest and femur lengths were greater in CBK and BCBK compared with JNC. Chest width, chest depth and hip width were similar in JNC and its crossbreds. Femur width was significantly greater in CBK compared with BCBK and JNC. Femur depth and chest girth were significantly greater in CBK and BCBK compared with JNC. Weight and fat yield in different carcass cuts were greater in crossbreds compared to JNC. Percent moisture, crude ash, and crude protein of meat were similar in JNC and its crossbreds. Percent crude fat in beef was significantly greater in JNC compared with its crossbreds. Beef shear force value, percent water holding capacity, juiciness and tenderness were significantly greater for JNC compared to its crossbreds. In conclusion, CBK and BCBK have shown greater growth rates and produced heavier carcasses with good degree of fatness when compared with JNC.

• Asian-Australasian Journal of Animal Sciences
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• 제28권11호
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• pp.1614-1623
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• 2015

The objectives of the current experiment were to study the response of the growth performance of early finishing gilts to different net energy (NE) concentrations in diets, and to compare the NE values of diets between calculated NE values and measured NE values using French and Dutch CVB (Centraal Veevoederbureau; Central Bureau for Livestock Feeding) NE systems. In a metabolism trail, the NE concentrations in five diets used for the growth trial were determined based on digestible nutrient concentrations, digestible energy, and metabolizable energy using a replicated $5{\times}5$ Latin square design with 10 barrows (initial body weight [BW], $39.2{\pm}2.2kg$). In a growth trial, a total of 60 early finishing gilts (Landrace${\times}$Yorkshire; initial BW, $47.7{\pm}3.5kg$) were allotted to five dietary treatments of 8.0, 9.0, 10.0, 11.0, and 12.0 MJ NE/kg (calculated, as-is basis) with 12 replicate pens and one pig per pen in a 42-d feeding experiment. The NE and amino acid (AA) concentrations in all diets were calculated based on the values from NRC (2012). Ratios between standardized ileal digestible AA and NE concentrations in all diets were closely maintained. Pigs were allowed ad libitum access to feed and water. Results indicated that calculated NE concentrations in diets (i.e., five dietary treatments) were close to measured NE concentrations using French NE system in diets. The final BW was increased (linear and quadratic, p<0.05) with increasing NE concentrations in diets. Furthermore, average daily gain (ADG) was increased (linear and quadratic, p<0.01) with increasing NE concentrations in diets. There was a quadratic relationship (p<0.01) between average daily feed intake and NE concentrations in diets. Feed efficiency (G:F) was also increased (linear, p<0.01) as NE concentrations in diets were increased. The NE intake per BW gain (kcal NE/kg of BWG) was increased (linear, p<0.01) with increasing NE concentrations in diets that were predicted from both French and Dutch CVB NE systems. Linear regression indicated that predictability of daily NE intake from the BW of pigs was very low for both French ($R^2$, 0.366) and Dutch CVB ($R^2$, 0.374) NE systems. In conclusion, increasing NE concentrations in diets increase BW, ADG, G:F, and NE intake per BW gain of early finishing gilts. The BW of early finishing gilts is not a good sole variable for the prediction of daily NE intake.

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1140-1149
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• 2015

This research aimed to define the energy requirement of Dorper and Hu Hybrid $F_1$ ewes 20 to 50 kg of body weight, furthermore to study energy requirement changes with age and evaluate the effect of age on energy requirement parameters. In comparative slaughter trial, thirty animals were divided into three dry matter intake treatments (ad libitum, n = 18; low restricted, n = 6; high restricted, n = 6), and were all slaughtered as baseline, intermediate, and final slaughter groups, to calculate body chemical components and energy retained. In digestibility trial, twelve ewes were housed in individual metabolic cages and randomly assigned to three feeding treatments in accordance with the design of a comparative slaughter trial, to evaluate dietary energetic values at different feed intake levels. The combined data indicated that, with increasing age, the net energy requirement for maintenance ($NE_m$) decreased from $260.62{\pm}13.21$ to $250.61{\pm}11.79kJ/kg^{0.75}$ of shrunk body weight (SBW)/d, and metabolizable energy requirement for maintenance (MEm) decreased from $401.99{\pm}20.31$ to $371.23{\pm}17.47kJ/kg^{0.75}$ of SBW/d. Partial efficiency of ME utilization for maintenance ($k_m$, 0.65 vs 0.68) and growth ($k_g$, 0.42 vs 0.41) did not differ (p>0.05) due to age; At the similar condition of average daily gain, net energy requirements for growth ($NE_g$) and metabolizable energy requirements for growth ($ME_g$) for ewes during late fattening period were 23% and 25% greater than corresponding values of ewes during early fattening period. In conclusion, the effect of age upon energy requirement parameters in the present study were similar in tendency with previous recommendations, values of energy requirement for growth ($NE_g$ and $ME_g$) for Dorper and Hu crossbred female lambs ranged between the NRC (2007) recommendation for early and later maturating growing sheep.

• 대한환경공학회지
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• 제33권9호
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• pp.636-643
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• 2011

초음파를 사용한 슬러지 가용화는 슬러지 부피 감소 및 혐기성 바이오가스 생산시의 소화효율 강화를 위해 그 이용이 증가하고 있다. 본 연구에서는 세 종류의 슬러지(G 하수처리장의 반송슬러지, 잉여슬러지와 혼합슬러지)를 대상으로 가장 효율적인 가용화를 위해 전기장단독처리와 초음파단독처리 및 전기장-초음파 복합처리를 연구하였다. 폐쇄된 회로로서, 평균 $0.7m^3/h$의 유량으로 200 L의 슬러지(이는 1시간당 3.5회 처리에 해당)를 24시간 동안 84회까지 연속적으로 가용화 공정을 통과시켰다. 전기장만 단독으로 적용하였을 때의 경우 슬러지 종류와 관계없이, 처리 전과 후에 어떤 sCOD/tCOD 변화도 발생하지 않았다. 그러나 초음파 단독 또는 복합된 공정을 이용한 경우 통과횟수에 따라 두 방법 모두 슬러지 가용화율이 증가하였고 복합된 경우 더 크게 증가하였다. 또한, 입자의 직경(0.9)과 직경(0.5)이 원 슬러지보다 감소하는 동시에 VSS/TSS는 2~6% 범위까지 감소하였다. 잉여슬러지와 혼합슬러지에는 전기장 및 초음파 복합처리가 더 적합했던 것에 비해 반송슬러지는 초음파 처리가 더 가용화를 효과적으로 촉진하였다. 가장 효율적인 슬러지 파괴를 위해서는 슬러지 종류에 따라 가용화 공정이 선택적으로 적용되어져야 할 것으로 판단할 수 있었다.

• 대한환경공학회지
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• 제29권12호
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• pp.1371-1380
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• 2007

폐플라스틱 열분해 재생유의 품질향상을 위하여 불안정화 요인 규명 연구를 수행하였다. 열분해 재생유를 오존화반응시킨 결과 이중결합 불포화탄화수소가 알데히드와 케톤으로 변하면서 폐HDPE 열분해 재생유의 약 45%는 1-알켄구조불포화탄화수소이며, 폐PP 열분해 재생유는 $\sim47%$의 secondary alkene과 $\sim20%$의 primary alkene을 포함한 약 73 wt% 불포화탄화수소를 함유하고 있음을 확인하였다. 오존화 반응 후 기름의 냄새, 짙은 색도가 개선되었는데 이중결합 불포화탄화수소와 관련이 있음을 확인하였다. 저장 용기 별 시험에서는 철제 캔이 갈색유리병보다 좀더 기름의 질 변화를 일으킴을 보여주었다. 기름에 투입된 항산화제는 2-3일 만에 90여 wt%가 소모되면서 항산화제 기능으로 인하여 불포화탄화수소올레핀은 50일이 지나도 안정하였다. 불순물질 제거 흡착여과 시험에서는 실리카, 활성탄, 알루미나 순으로 불순물질 제거효율이 좋으나 수분의 제거효율은 낮았다. 무수탄산나트륨과 무수황산마그네슘이 수분 및 침전물 제거효율이 모두 높으나 실제 열분해재생유 생산 공정에 원가상승을 거의 하지 않은 무수탄산나트륨을 투여 혼합 여과하여 기름의 품질 향상을 달성하였다.

• 한국인쇄학회지
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• 제31권1호
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• pp.39-49
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• 2013

Nowadays the printing market has shift from 2D(two dimension) industry to 3D(three dimension) industry, along with IT. With rapidly changing market, it's true that the effort to develop the printing materials and upgrade the printing qualities is produced actively in the country. Particularly, the differences in printing materials can often determine the quality of printings in the printability. In the case of the printability of offset, 9 items(paper, ink, order of printing, ink supply, blowing-up halftone, grey balance, key color(base color), overlap efficiency, quality at the halftone dot reproduction etc.) are usually considered as the important factors and used to estimate the printability at abroad. However, in domestic, ink-jet paper is not used for the printing/publishing by ink-jet printing for digital, but done mainly for offset printing. Because the paper of gloss coated type, which is the ink-jet paper, has high price, it's too hard to manufacture massively printing/publishing. Also, in the case of the paper of uncoated type, in spite of its reasonable price rather than the former, the type of uncoated one also has demerit that the ink-jet paper has a clear difference between the front and the back. Therefore, it's tough reality that Ink Jet paper is hardly taken advantage of as the printing/publishing. Thus, what is done in the first to print and/or publish on ink-jet paper is that the front and the back must be printed evenly, and appropriate to the printability of ink-jet. Although there're some kinds of ink-jet paper in the country, it has not been produced in true domestic production yet. In addition, thanks to the brightness of fluorescence brightening agent, the foreign product can offer the good-qualified one-time printing. But when it comes to the printing/publishing, there're difficulties that it may cause the Ocular Fatigue because of long-term exposure of the eyes to text. This research tries to find out the optimum ink-jet paper in domestic for the printing/publishing by studying on the printability of ink-jet on digital web-printing. And it also tries to look for the paper's brightness which can be reduce the possibility to cause the consumers' Ocular Fatigue.

• 방사성폐기물학회지
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• 제13권1호
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• pp.11-19
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• 2015

원자력발전소 증설에 따라 핵연료 피복관의 생산량이 증가 할 것으로 예상되며, 튜브 제조 시 발생되는 지르코늄(Zr) 스크랩 역시 증가 할 것으로 판단된다. 지르코늄(Zr) 정련기 대용량화와 회수율 향상을 위한 사전 연구로서 LiF-KF-ZrF₄ 불화물의 염에서 다전극을 이용하여 전해정련실험을 실시하였다. LiF-KF-ZrF₄염에서는 -0.8 V(vs.Ni)에서 환원전위가 관찰되었으며, 분극 거동 관찰 결과 전극의 개수가 증가할수록 셀의 저항이 낮아져 인가전류량이 증가하였다. 6개의 다 전극을 이용하여 정련 실험을 한 결과 가장 낮은 전류밀도인 25.64 mA/cm²조건에서 98%의 회수율로 가장 높은 회수율은 보였다. XRD 및 TG 분석 결과 순수한 Zr이 회수되었으며, ICP 분석결과 양극재의 기본 불순물 함량을 포함한 순도 97.8% 보다 낮은 불순물의 함량을 포함한 순도 99.92%의 Zr을 나타내었다. 폭 20 mm 높이 65 mm의 전극 6개를 사용시 전력소모율은 7.15 kWh/Kg으로 크롤 공정대비 39.7% 전력을 소모하게 된다. 다 전극 사용 시 단일 전극 사용에 비해 인가전류와 셀 효율 및 회수율 증대로 대용량화를 위한 효율적인 기술로 판단된다.