• Asian-Australasian Journal of Animal Sciences
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• 제26권5호
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• pp.691-699
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• 2013

Three experiments were conducted to evaluate the metabolizable energy (ME) value, standardized ileal digestibility (SID) of amino acids (AA) of soybean meal (SBM), soy protein concentrate (SPC) and fermented soybean meal (FSBM), and the application of these products in early-weaned piglets. In Exp. 1, four barrows with initial body weight (BW) of $14.2{\pm}1.4$ kg were used in a $4{\times}4$ Latin square design. The diet 1 contained corn as the only energy source. The other three diets replaced 25% of corn in diet 1 with one of the three soybean products, and the digestable energy (DE) and ME contents were determined by difference. In Exp. 2, four barrows (initial BW of $18.2{\pm}1.5$ kg) were fitted with ileal T-cannulas and allotted to a $4{\times}4$ Latin square design. Three cornstarch-based diets were formulated using each of the soybean products as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. In Exp. 3, ninety six piglets (initial BW of $5.6{\pm}0.9$ kg) weaned at $21{\pm}2$ d were blocked by weight and assigned to one of three treatments for a 21-d growth performance study. The control diet was based on corn and SBM, the two treatments' diets contained either 10% SPC or FSBM and were formulated to same SID lysine to ME ratio of 3.6 g/Mcal. The results showed that the ME content of SPC was greater than SBM (p<0.05). The SID of most AA in SPC was greater than the SID of AA in SBM (p<0.05). For the essential AA, the SID of histidine, isoleucine, leucine, lysine and threonine in FSBM were greater than in SBM (p<0.05). Even though they were fed same SID lysine to ME ratio of 3.6 g/Mcal diets, pigs fed SPC and FSBM diets had greater weight gain, G:F (p<0.05) and better fecal score (p<0.05) than pigs fed SBM diet. In conclusion, SPC showed a higher ME content and SID of AA than the SBM. SID of some essential AA in FSBM was higher than SBM and was similar with SPC. But the lower antigenic proteins and anti-nutritional factors content in SPC and FSBM may be the main factors affecting the performance of early-weaned piglets rather than the increased ME content and SID of AA.

• Journal of Nutrition and Health
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• 제25권7호
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• pp.543-554
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• 1992

True metabolizable energy(TME) is believed a better indicator for animal performance than apparent metabolizable energy (AME) for excluding the endogenous energy losses from excreta, However few researches have been conducted to compare superiority of any energy systems through practical animal feeding tests. Present study was to compare the energy systems in young chicks in terms of predictability of energy intake for the birds performances including body energy retention and of methodological accuracy by evaluating reproducibility and additi-vity of energy values of feed ingredients and compound diets. Five ingredients such as yellow corn wheat soybean meal fish meal and wheat bran were measured for their various biological energy values. in the first feeding trial chicks were restric-ted-fed the basal diet at 80, 60 and 40% on weight basis of the amount of feed ingested by chicks fed ad libitum the same diet. chicks in the second trial were also restricted-fed diets at levels of 80, 70, 60 and 50% on energy basis of the amount consumed by the basak duet group fed ad libitum The diets in the latter trial were however composed of differeent formulations from the basal diet. One-week-old Single Comb White Leghorn male chicks were individually alloted in a cage on 10 cages/treatment basis and fed the diets for 14 days. Individual carcass energy was measured after the feeding trials. Coefficients of variation of energy measurements were lesser for nitrogen-corrected AME and TME(AMEn & TMEn respectively) than AME and TME values suggesting taht reprodu-cibility of energy determinations by former systems could be better than the latters. The coeffi-cients for AME and TME were almkost of the same values. Additivity obtained by the rations between the calculated values and catual measurements appeared quite satisfactory for all the energy systems. Those of AME and TME however were relatively better than the other systems. Regression coefficient ${r}^2$ between energy intake by various systems and chick performances appeared higher for TME, AMEn and TMEn than AME implying that the former systems could provide better predictability for body weight gain and energy retention than the AME. The ${r}^2$ values for TME and AMEn particularly for body weight gain were on the average 0.967 and 0.960 respectively. In conclusion TME or AMEn can be recommended as choice for dietary energy system in terms of performance predictability of the birds and of procedural convenience for the measurements.

• 센서학회지
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• 제11권4호
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• pp.209-217
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• 2002

광섬유 ROTDR (Rayleigh Optical Time Domain Reflectometry)을 이용하여 침입자를 높은 감도와 넓은 영역에서 탐지할 수 있는 매설형 광섬유 센서의 개발에 관한 실험을 수행하였다. 단위 길이당 넓은 면적을 감지 할 수 있는 매설형 광섬유 감지부를 설계 제작하고, 인가된 침입물체의 하중에 따른 신호특성을 고찰하였다. 일반 광통신용인 직경 1.5mm와 3.5mm인 광섬유를 길이 각각 4km를 사용하여 광섬유 굽힘손실을 발생시키는 침입감지 장치를 설계 제작하고, 상용 ROTDR의 조건설정은 파장 $1.55{\mu}m$, 거리범위 5km, 펄스폭 20 ns, S/N비가 5.7인 시스템으로 실험하였으며, 광섬유 RODTR 센서시스템의 측정신호로부터 침입자 신호를 찾아내기 위한 측정신호처리 시스템을 구성하였다. 광섬유 센서의 인가하중과 광손실값과의 관계는 거의 선형적으로 변함을 보였으며, 공간분해능은 2m로 측정되었고, 침입감지면적은 단위길이당 $1.3m^2$이고, 감도는 0.17dB/kg으로 외부 침입물체등을 감지하기에 충분히 높은 감도와 감지영역을 가짐을 알 수 있다.

• 농업과학연구
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• 제27권1호
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• pp.48-53
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• 2000

1. 난중(卵重) 및 진동량 계측 시스템은 로드셀 1개를 이용한 기존의 방법을 로드셀 배치 I, 계란의 이송방향과 평행하게 같은 방향으로 부착한 방법을 로드셀 배치 II 로 하였고 로드셀 2개를 이용하여 서로 마주보도록 부착한 방법을 로드셀 배치 III, 2 개의 로드셀이 계란의 이송방향과 평행하게 같은 방향으로 부착한 방법을 로드셀 배치 IV로 구성하여 난중(卵重) 및 진동량을 측정, 분석 하였다. 2. 4가지의 로드셀 배치에 따른 난중(卵重)측정결과 로드셀 배치 I, 로드셀 배치 II, 로드셀 배치 III, 로드셀 배치 IV에 의한 난중(卵重)평균 오차가 각각 1.2128g, 0.5953g, 0.7786g, 0.2793g으로 로드셀 2개를 계란 이송방향과 평행하게 부착한 방법이 난중(卵重) 평균 오차가 가장 낮게 나와 정밀도가 매우 높음을 알 수 있었다. 3 계란 자동 선별기를 이용하여 대란 등급의 계란 선별시 X, Y, Z축 방향에서 평균 진동량이 각각 $5.1937{\times}10^{-3}G$, $9.3604{\times}10^{-3}G$, $16.8657{\times}10^{-3}G$로서 Z축방향의 진동값이 X, Y방향보다 상대적으로 크다는 것을 알 수 있었다.

• 한국철도학회논문집
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• 제20권3호
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• pp.329-338
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• 2017

최근 철도차량용 보조전원장치는 시스템의 경량화를 위해 기존 60Hz 저주파 변압기를 제거하고 고주파 구동과 절연 특성을 갖는 '절연형 dc/dc 컨버터'를 적용하는 구조가 주목받고 있다. 본 논문에서는 '절연형 dc/dc 컨버터를 적용한 보조전원장치 구조'에 대해서 설명하고, 다양한 분석을 통해 보조전원장치의 고효율 및 경량화에 적합한 dc/dc 컨버터 및 구조를 제안하고자 한다. 대용량 IGBT 소자의 고주파 스위칭(경량화)을 위해 필수적인 '영전압-영전류-스위칭'특성을 갖는 '공진형 컨버터'를 활용하여 다양한 보조전원장치용 전력변환장치 구조(1-Stage와 2-Stage)를 제안하였고, 각각의 구조에 적합한 컨버터 회로를 선정한 후 설계 및 시뮬레이션을 통해 비교하였다. 1-Stage 구조의 경우 공진형 컨버터만을 사용하였고, 2-Stage 구조의 경우 공진형 컨버터와 공진형 컨버터의 입력전압 변동을 최소화하는 Pre-regulator를 적용하였다. Pre-regulator로서 감압 컨버터 또는 승압 컨버터를 각각 적용하여 서로 다른 2-Stage 구조를 구성하고 각 방식의 손실을 비교하였다. 회로에 사용되는 소자들의 전압 및 전류 스트레스를 고려하여 소자를 선정하고 시뮬레이션을 통해 동작을 검증하였으며, 손실 분석을 통해 고효율 및 경량화에 가장 적합한 구조 및 회로를 제안하였다.

• Elastomers and Composites
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• 제40권4호
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• pp.266-271
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• 2005

실리콘 고무 (SR) 함량이 EPDM/SR 블랜드의 열안정성에 미치는 영향을 고찰하기 위하여 질소 분위기하에서 TGA 열분석을 수행하여 열분해온도, 열분해 활성화에너지 ($E_d$), 열분해 후 잔여량 등 열안정성 인자들을 알아보았다. 실험 결과, SR 첨가량이 10 wt%일 경우 블랜드의 열분해 곡선은 순수한 EPDM 고무와 비슷한 경향을 보였으나, SR 함량이 증가함에 따라 블랜드의 열분해는 더 높은 온도에서 진행되었다. 순수한 EPDM 고무인 경우 $E_d$ 값은 처음에는 서서히 감소하다가 분해분율이 20 wt%이상에서는 거의 일정한 값을 나타내었다. SR 함량이 10-20 wt%일 경우 블렌드의 $E_d$은 순수한 EPDM 고무의 경우보다 높은 값을 나타내었으며, 분해분율이 증가함에 따라 점차 감소하였다. 반면에 SR 첨가량이 30 wt%일 경우 블렌드의 $E_d$은 순수한 EPDM 고무의 경우보다 낮은 값을 나타내었으며, 분해분율이 증가함에 따라 서서히 감소하였다. 또한, $800^{\circ}C$에서의 열분해 후 잔여량은 SR 함량이 증가함에 따라 증가하였으며, 이는 분해된 실록산 그룹이 경화된 수지의 표면에 보호막을 형성하여 열전달 및 확산을 제한한 것으로 판단된다.

• 농업과학연구
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• 제15권2호
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• pp.143-152
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• 1988

우리나라 보급(普及)된 동력경운기(動力耕耘機)에 탑재(搭載)된 6, 7.5kW 수냉식(水冷式) 4 Cycle 디젤 기관(機關)의 성능향상(性能向上), 중량경감(重量經減), 생산비(生産費) 절감(節減)을 도모하고져, 기관(機關) 기획(企劃), 설계시(設計時) 고려할 수 있는 기본(基本) 자료(資料)를 얻기 위하여 동력경운기(動力耕耘機) 탑재용(搭載用) 기관(機關)의 기존(旣存)의 타(他) 부품(部品)은 고정(固定)하고 Flywheel의 중량(重量)만을 32.2, 29.7, 26.4, 24.2kg 등(等)의 4수준(水準)으로 감소(減少)시키면서, 출력(出力), 열과소비율(熱科消費率), Motoring loss, Toque, 진동량(振動量), 열효율(熱效率), 등(等)을 측정(測定) 분석(分析)한 결과(結果)는 다음과 같다. 1. 기관(機關)의 최대(最大) 출력(出力)은 6kW 기관(機關)은 7.43kW, 7.5kW 기관(機關)은 7.85kW이었으며 Flywheel의 중량(重量)을 32.2kg에서 24.2kg으로 감소(減少)시켰을때 6kW 기관(機關)은 7.70kW로 0.27kW의 출력(出力)이 증가(增加)되었고 7.5kW 기관(機關)은 7.85kW에서 8.25kW로 0.39kW의 출력(出力) 향상(向上)이 되었다. 2. Flywheel의 중략(重量)을 감소(減少)시킴으로서 결과소비율(練料消費率)은 6kW 기관(機關)은 300.8g/kW-h에서 296.8g/kW-h로 4.0g/kW-h, 7.5kW 기관(機關)은 313.6g/kW-h로 0.8g/kW-h로 0.8g/kW-h가 감소(減少)하였다. 3. 기관(機關)의 효율(效率)은 Flywheel의 중량(重量)을 32.2kg에서 24.2kg으로 감소(減少)시켰을 때 6kW 기관(機關)은 76.1에서 76.8로 0.7%, 7.5kW 기관(機關)은 76.68에서 77.02kW로 0.34%가 증가(增加)하였다. 4. Flywheel 중량(重量)이 32.2kg에서 24.2kg으로 감소(減少)함에 따라 진동량(振動量)은 6kW 기관(機關)의 경우 X축(軸)및 Z축(軸)에서는 약간 감소(減少)하는 경향(傾向)이 있으며 7.5kW 기관(機關)의 경우 모든 방향(方向)과 6kW 기관(機關)의 Y축(軸)에서는 약간 증가(增加)하는 경향(傾向)이었다. 5. Motoring loss는 flywheel 중량(重量)이 32.2kg 2200 rpm (6/7.5kW)에서는 2.33/2.46kW이었고 24.2kg에서는 1.76/1.84kW로 감소(減少)하였다. 위의 결과(結果)를 종합(綜合)하여 고찰(考察)해 보면, 이론식(理論式)에 의한 Flywheel의 중량(重量) 6kW 기관(機關)이 19.7kg 이었고 7.5kW 기관(機關)은 24.59kW이었으며 실험결과(實驗結果) 7.5kW 기관(機關)은 7kg, 6.0kW 기관(機關)은 10kg 정도 감소(減少)시켜 기관(機關)의 건중량(乾重量)을 감소(減少)시키는 것이 타당한 것으로 인정(認定)된다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권7호
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• pp.990-995
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• 2014

The objective of this experiment was to determine the concentration and digestibility of crude protein (CP) and amino acid (AA) in meat meal (MM), and to compare these values with the respective values in soybean meal (SBM). Six barrows (initial body weight = $66.9{\pm}3.8kg$) surgically fitted with a T-cannula at the distal ileum were allotted to a replicated $3{\times}3$ balanced Latin square design with 3 diets and 3 periods. Two experimental diets containing test ingredients as the sole source of AA were prepared to estimate the apparent ileal digestibility (AID) for CP and AA by the direct method. An N-free diet was also prepared to estimate basal endogenous losses of CP and AA. All experimental diets contained 5% chromic oxide as an indigestible index. Each period consisted of a 5-d adaptation period and a 2-d of ileal digesta collection period. Ileal digesta samples were collected from 0900 to 1700 on d 6 and 7 of each period. The concentrations of CP, Lys, Met, and Trp in MM and SBM were analyzed to be 64.1, 3.5, 1.1 and 0.6, and 45.6, 2.8, 0.8, and 0.3%, respectively. The AID of all AA except Gly in MM was less (p<0.05) than in SBM. The AID of Lys, Met, and Trp in MM was estimated to be 56.0, 71.7, and 47.1%, respectively. The SID of all AA in MM was less (p<0.05) than in SBM. The SID of Lys, Met, and Trp was 65.1, 79.2, and 78.5%, respectively. In conclusion, the CP and AA contents in MM were greater than those in SBM whereas the ileal digestibility of all AA in MM was less than in SBM.

• Asian-Australasian Journal of Animal Sciences
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• 제26권2호
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• pp.195-201
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• 2013

A lab-scale ensiling study was carried out to investigate the fermentation quality of water hyacinth (WH) supplemented with molasses, rice bran, as an absorbent, and an inoculant in the form of fermented vegetable juice and their combinations. After wilting the water hyacinths for 7 h to a dry matter (DM) content of 240 to 250 g/kg, the following treatments were applied: i) Control (C), WH only; ii) WH with sugarcane molasses at 40 g/kg WH (CM); iii) WH inoculated with fermented vegetable juice at 10 ml/kg WH (CI); iv) CM and CI (CMI) combined; v) WH with 150 g rice bran/kg WH (CA); vi) CA and CI combined (CAI); vii) CA and CM combined (CAM); and viii) CA, CM and CI combined (CAMI). After application of additives, the differently treated forages were mixed and ensiled in triplicates in 1,500-ml polyethylene jars. After ensiling for 3 d, pH values in all treatments, except C and CI, had decreased to approximately 4.0 and remained low till 14 d. After 56 d, pH had increased between 0.4 to 0.9 pH-units compared to those at 14 d. The ammonia nitrogen ($NH_3$-N) concentration ranged from an acceptable level in treatment CM (8 g/kg N) to a high $NH_3$-N value in treatment CMI (16 g/kg N). Lactic acid formation was higher in CI than in all other treatments. Butyric acid contents, which indicate badly fermented silages, were low in all silages (<2 g/kg DM). There were two-way interactions (p-values from <0.001 to 0.045) for almost all fermentation end-products and pH, except for the molasses${\times}$inoculant interaction on $NH_3$-N (p = 0.26). Significant 3-way interactions were found on all observed variables except for weight losses of silages. It is concluded that conserving wilted WH as silage for ruminants may be improved by the addition of molasses or rice bran.

• Asian-Australasian Journal of Animal Sciences
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• 제26권2호
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• pp.227-232
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• 2013

Phytate is not only an unavailable source of phosphorus (P) for broilers but it also acts as an anti-nutrient, reducing protein and mineral absorption, increasing endogenous losses and reducing broiler performance. The objective of this study was to investigate the anti-nutritional effects of phytate by including high levels of phytase in diets not severely limited in available P. A total of 768 male Arbor Acres broilers were distributed in six treatments of eight replicate pens of 16 birds each consisting of a positive control diet (PC), positive control with 500 FTU/kg phytase, negative control (NC) diet with lower available P and calcium (Ca) levels and the same NC diet with 500, 1,000 or 1,500 FTU/kg phytase. Body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and mortality were determined at 21 and 35 d of age while foot ash was determined in four birds per pen at 21 d of age. FI, FCR and foot ash where not affected by the lower mineral diets at 21 d of age nor by the enzyme inclusion but broilers fed lower Ca and available P diets had lower BWG. At 35 d of age no difference was observed between broilers fed the positive or NC diets but broilers fed 500, 1,000 and 1,500 FTU/kg on top of the NC diet had better FCR than broilers fed the positive control diet. When compared to birds fed a diet adequate in P, birds fed the same diet included with 500, 1,000 and 1,500 FTU/kg of phytase in marginally deficient available P and Ca diets had an improvement of performance. These results support the concept that hydrolysing phytate and reducing the anti-nutritional effects of phytate improves bird performance on marginally deficient diets that were not covering the P requirement of birds.