• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.12
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• pp.12-20
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• 1993

In a conventional adaptive echo canceller, an ADF(Adaptive Digital Filter) with TDL(Tapped-Delay Line) structure modelling the echo path uses the LMS(Least Mean Square) algorithm to compute the coefficients, and NET detector using energy comparison method prevents the ADF to update the coefficients during the periods of the NET signal presence. The convergence speed of the LMS algorithm depends on the eigenvalue spread ratio of the reference signal and NET detector using the energy comparison method yields poor detection performance if the magnitude of the NET signal is small. This paper presents a new adaptive echo canceller which uses the pre-whitening filter to improve the convergence speed of the LMS algorithm. The pre-whitening filter is realized by using a low-order lattice predictor. Also, a new NET signal detection algorithm is presented, where the start point of the NET signal is detected by computing the cross-correlation coefficient between the primary input and the ADF output while the end point is detected by using the energy comparison method. The simulation results show that the convergence speed of the proposed adaptive echo canceller is faster than that of the conventional echo canceller and the cross-correlation coefficient yields more accurate detection of the start point of the NET signal.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.7
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• pp.1035-1039
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• 1999

Four ruminally cannulated buffalo bulls were fed mottgrass diets using a $4{\times}4$ Latin square design. Treatments were arranged factorially and consisted of mottgrass fertilized with 0 for Kg nitrogen (N) per acre and harvested at 40 and 60 days of age. Nitrogen fertilization improved the concentrations of neutral detergent fiber (NDF), and acid detergent fiber (ADF) in early-cut mottgrass (ECM) but, the acid detergent lignin (ADL) contents were higher in the late-cut mottgrass (LCM). The crude protein (CP) contents of the mottgrass decreased with advancing maturity, but N fertilization increased CP at both maturities. The intake of dry matter (DM), organic matter (OM), CP, NDF and ADF were higher by buffalo bulls fed ECM than those fed LCM. The ruminal pH increased in first 6 hours post feeding in animals fed N fertilized mottgrass and may be due to higher concentration of ruminal ammonia. The digestibilities of DM, OM, CP, NDF and ADF were higher by buffalo bulls fed ECM than those fed LCM. However, the application of N fertilizer did not affect the digestibilities of these nutrients.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.1
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• pp.1-6
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• 1990

The objective of this experiment was to compare the effect of pH-regulated alkaline hydrogen peroxide (AHP) treatment of rice straw with those of sodium hydroxide (NaOH) and anhydrous ammonia ($NH_3$) treatments on in sacco digestivility. Three non-lactating ruminally cannulated Holstein cows were fed a diet containing 90% forage and 10% concentrate on a dry matter (DM) basis. The AHP treatment significantly (p<0.05) reduced acid detergent lignin content of the straw, resulting in significant (p<0.05) increase of neutral detergent fiber (NDF), acid detergent fiber (ADF) and cellulose concentrations. Disappearance rates of DM and NDF of the straw significantly (p<0.05) increased at the incubation time of 24 h. On the other hand, those of ADF and cellulose were significantly (p<0.05) higher at the incubation time of 12 h than those of the others. The effective degradability of DM(EDDM), NDF(EDNDF), ADF(EDADF) and cellulose (EDCE) were determined using in sacco nylon bag technique on the basis of 0.05/h solid outflow rate. The greater differences (p<0.05) of EDDM, EDNDF, EDADF and EDCE were found between AHP treated straw and the others. In general, AHP treatment of the straw recorded higher digestion coefficients than untreated straw as well as NaOH and $NH_3$ treated straws. The results of this study demonstrate that AHP treatment can be used as a effective method for improving the nutritive value of rice straw for ruminants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.4
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• pp.403-409
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• 1989

Dietary fiber(DF) content and their properties were analyzed in some common vegetables such as Squash(leaf), Water cress, Garland chrysanthemum, Leek and sweet potato(stem). DF was analyzed by the method of detergent fractionation. Values for neutral detergent fiber(NDF), acid detergent fiber(ADF), lignin, hemicellulose were obtained. NDF for most samples was $13.83%{\sim}24.31%$, ADF was $11.99%{\sim}21.03%$, lignin was around $0.56%{\sim}3.00%$, hemicellulose was about $1.33%{\sim}3.88%$, cellulose was $9.08%{\sim}14.87%$ except sweet potato(leaf) (20.47%). This paper describes two properties of the fiber-of commonly eaten vegetables ; water-holding capacity(WHC) and metal binding. The capacity of the acetone dried powder (ADP) to hold water was estimated. The WHC measurements differed from 7.49 per 9 of ADP for Water cress to 11.09 per 9 of ADP for Leek. The binding of Fe, Zn in NDF. ADF obtained from five fiber sources was examined under two pH conditions ; 1) pH2.1, 2) pH6.1. Fe, Zn binding increased with higher pH and differed from DF sources.

• Korean Journal of Materials Research
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• v.5 no.5
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• pp.503-511
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• 1995

금속/실리콘계에 대한 이온선 혼합시의 비정질상 및 결정상 형성여부를 예측할 수 있는 모델(ADF Model)과초기 결정상 예측 모델(PDF Model)의 적용을 실험적으로 조사하기 위하여 Ni/Si계에 대한 이온선 혼합을 온도와 이온선량을 변수로 하여 행하였으며 상형ㅅㅇ과정을 해석하였다. 이온선 혼합은 80keV가속기를 이용하여 상온~20$0^{\circ}C$의 온도 범위에서 1.0 $\times$ $10^{15}$Ar^{+}$/$cm^{2}$~2.0 $\times$ $10^{-16}$Ar^{+}$/$cm^{2}$의 이온선량을 변화시키면서 실험하였고, 상분석은 TEM과 GXRD를 이용하였다. Ni/Si게에 대한 ADF값은 0.804로 양의 값을 가지므로 이온선 혼합시 비정실상이 형성되고, $Ni_{2}$Si상이 다른 화합물상보다 훨씬 큰 음의 PDF값을 갖으므로 초기 결정상이 $Ni_{2}$Si가 될 것을 예측하였다. 이러한 예측은 실험결과와 매우 잘 일치하였다. 이상의 연구결과로부터 ADF 및 PDF모델을 이용하여 박막에서 형성되는 상을 보다 정확히 예측할수 잇음을 알 수 있었다.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.31.4-32
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• 2018

The ADF-S (AKARI Deep Field - South) toward South Ecliptic Pole is one of the deep survey fields designed for the study of Cosmic Infrared Background (CIB). Owing to the easy accessibility with space missions and its low background brightness, the deep extragalactic survey was initiated by AKARI deep far-infrared observations and it will be performed by other future missions (e.g., Euclid, NISS, SPHEREx). The recent optical survey with KMTNet enabled us to identify the optical counterparts for dusty star-forming galaxies such as ULIRG, DOG, SMG. In addition, the NISS will perform the valuable spectro-photometric survey in the ADF-S. Those multi-wavelength data sets helps to trace the major galaxy population contributing to the CIB. Here, we introduce the extragalactic survey with the NISS and report the current status of the multi-wavelength extragalactic studies in the ADF-S.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.2
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• pp.187-193
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• 2014

As a result of the cost of grains, the replacement of grains by co-products (i.e. DDGS) in feedlot diets is a common practice. This change produces diets that contain a lower amount of starch and greater amount of fibre. Hypothetically, combining feed grade urea (U) with slow release urea (Optigen) in this type of diet should elicit a better synchrony between starch (high-rate of digestion) and fibre (low-rate of digestion) promoting a better microbial protein synthesis and ruminal digestion with increasing the digestible energy of the diet. Four cannulated Holstein steers ($213{\pm}4$ kg) were used in a $4{\times}4$ Latin square design to examine the combination of Optigen and U in a finishing diet containing different starch:acid detergent fibre ratios (S:F) on the characteristics of digestive function. Three S:F ratios (3.0, 4.5, and 6.0) were tested using a combination of U (0.80%) and Optigen (1.0%). Additionally, a treatment of 4.5 S:F ratio with urea (0.80% in ration) as the sole source of non-protein nitrogen was used to compare the effect of urea combination at same S:F ratio. The S:F ratio of the diet was manipulated by replacing the corn grain by dried distillers grain with solubles and roughage. Urea combination did not affect ruminal pH. The S:F ratio did not affect ruminal pH at 0 and 2 h post-feeding but, at 4 and 6 h, the ruminal pH decreased as the S:F ratio increased (linear, p<0.05). Ruminal digestion of OM, starch and feed N were not affected by urea combination or S:F ratio. The urea combination did not affect ADF ruminal digestion. ADF ruminal digestion decreased linearly (p = 0.02) as the S:F ratio increased. Compared to the urea treatment (p<0.05) and within the urea combination treatment (quadratic, p<0.01), the flow of microbial nitrogen (MN) to the small intestine and ruminal microbial efficiency were greater for the urea combination at a S:F ratio of 4.5. Irrespective of the S:F ratio, the urea combination improved (2.8%, p = 0.02) postruminal N digestion. As S:F ratio increased, OM digestion increased, but ADF total tract digestion decreased. The combination of urea at 4.5 S:F improved (2%, p = 0.04) the digestible energy (DE) more than expected. Combining urea and Optigen resulted in positive effects on the MN flow and DE of the diet, but apparently these advantages are observed only when there is a certain proportion of starch:ADF in the diet.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.510-521
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• 1998

The effects of two types of protein, soybean meal (SBM) and fish meal (FM); and two types of energy supplements, corn flour (CF) and paper pulp (PP), on intake of guinea grass (Panicum maximum), fibre digestion and microbial activities in four Merino rams with an average weight of $54.4{\pm}4.5kg$ were studied. Each animal was fitted with a ruminal cannula and a duodenal cannula at the proximal position. The animals were fed twice daily with chopped guinea grass (5 cm) ad libitum and one of the four dietary supplements: 170 g FM+268 g PP; 170 g FM+268 g CF; 200 g SBM+200 g PP or 200 g SBM+200 g CF. All the supplements were mixed with 100 g molasses. In sacco and in vivo digestibilities, digesta flow rates, fermentation and microbial population were studied in a $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement of dietary treatments. The effects of energy or protein sources were not significant on grass intake of sheep. The potential degradabilities of NDF and ADF were not significantly affected by any of the supplements. However, the energy and protein sources had significant efects on disappearance rate of NDF and ADF. The disappearance rate of both NDF and ADF were significantly (p < 0.05) higher in animals fed PP when compared to animals fed CF. Animals fed FM also showed significantly (p < 0.03) higher disappearance rate of ADF than those fed SBM. Animals fed PP showed better digestion in the rumen and total tract. Total flow of NDF and ADF through the duodenum was not significantly affected by the various supplements. The mean rumen pH values (5.8-6.1) were not significantly different among the four different diets. The concentration of rumen ammonia was significantly (p < 0.0001) higher in animals fed SBM (235-266.4 mg N/L) supplement than in animals fed FM (174.9-179.7 mg N/L), while total VFA concentration was not significantly affected by both energy and protein supplements. Mean values of total VFA ranged from 72.5-82.3 mM. Molar proportions of acetate, propionate and butyrate were typical of a roughage type fermentation. Molar proportion of acetate was significantly (p < 0.0001) higher in sheep fed PP when compared to sheep fed CF. Animals fed FM had higher total viable bacterial counts, while animals fed CF showed higher protozoal numbers. Proportions of cellulolytic bacteria were only slightly higher in animals fed SBM or PP.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.1
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• pp.1-8
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• 2007

This experiment was conducted to determine the effect of growth stage and variety on the yield and quality of whole crop rice (WCR) at National Livestock Research Institute, RDA from 2003 to 2005. Two types of rice ("Chucheong" for food and "Hamasari" for feed) were harvested at six different growth stages (heading, flowering, milk, dough, yellow ripening and fully ripening stage). Crude protein content decreased with progressed maturity at harvest. As growth stage delayed, TDN (total digestible nutrient) content of all rice varieties increased. The average TDN content of two type of rice was about 60% (59.3) which was calculated from ADF(acid detergent fiber) content. The contents of ADF and NDF(neutral detergent fiber) decreased with harvest maturity. The highest DM(dry matter) yield was at the ripening stage (p<0.05) and "Chucheong" gave higher yields than for "Hamasari". In this experiment, the DM yield of all varieties was low. The yield of TDN followed a similar trend to DM yield. According to this results that dough to yellow ripening stage of harvest maturity will be recommendable as proper harvest time for whole crop rice silage.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.554-561
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• 2017

Objective: This experiment was conducted as a $3{\times}2{\times}2$ factorial design to examine the effects of particle size (mean particle size of 331, 640, or $862{\mu}m$), evaluation method (direct vs indirect method) and adaptation duration (7 or 26 days) on the energy content and the apparent total tract digestibility (ATTD) of various chemical components in wheat when fed to finishing pigs. Methods: Forty-two barrows ($Duroc{\times}Landrace{\times}Yorkshire$) with an initial body weight of $63.0{\pm}0.8kg$ were individually placed in metabolic cages and randomly allotted to 1 of 7 diets with 6 pigs fed each diet. For the indirect method, the pigs were fed either a corn-soybean meal based basal diet or diets in which 38.94% of the basal diet was substituted by wheat of the different particle sizes. In the direct method, the diets contained 97.34% wheat with the different particle sizes. For both the direct and indirect methods, the pigs were adapted to their diets for either 7 or 26 days. Results: A reduction in particle size linearly increased the digestible energy (DE) and metabolizable energy (ME) contents as well as the ATTD of gross energy, crude protein, organic matter, ether extract (EE) and acid detergent fiber (ADF) (p<0.05), and had a trend to increase the ATTD of dry matter of wheat (p = 0.084). The DE, ME contents, and ATTD of gross energy, crude protein, dry matter and organic matter were higher (p<0.05) when determined by the direct method, but the ATTD of ADF, EE, and neutral detergent fiber were higher when determined by the indirect method (p<0.05). Prolongation of the adaption duration decreased the ATTD of neutral detergent fiber (p<0.05) and had a trend to increase the ATTD of EE (p = 0.061). There were no interactions between particle size and the duration of the adaptation duration. The ATTD of EE in wheat was influenced by a trend of interaction between method and adaptation duration (p = 0.074). The ATTD of ADF and EE in wheat was influenced by an interaction between evaluation method and wheat particle size such that there were linear equations (p<0.01) about ATTD of ADF and EE when determined by the direct method but quadratic equations (p = 0.073 and p = 0.088, respectively) about ATTD of ADF and EE when determined by the indirect method. Conclusion: Decreasing particle size can improve the DE and ME contents of wheat; both of the direct and indirect methods of evaluation are suitable for evaluating the DE and ME contents of wheat with different particle sizes; and an adaptation duration of 7 d is sufficient to evaluate DE and ME contents of wheat in finishing pigs.