• 한국통신학회논문지
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• 제31권7B호
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• pp.608-618
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• 2006

멀티미디어 스트리밍 서비스의 증가는 인터넷 콘텐츠의 새로운 국면으로 나타나고 있다. 특히, 무선이동통신망에서 증가하는 멀티미디어 응용에 대한 QoS 제공은 무엇보다 중요하다. 서비스 제공자는 클라이언트 가까이에 있는 프락시에서 자주 억세스되어지는 멀티미디어 스트림의 초기 세그먼트를 캐슁함으로써 성능을 향상 시킬 수 있다. 프락시는 서버로부터 스트림의 나머지 부분을 요구함과 동시에 클라이언트에 전송을 시작할 수 있다. 본 논문에서는 IETF의 RTSP 환경에서 프리픽스 캐슁 서비스를 무선망에 적용시키고, 무선 상황이나 핸드오프 시에 네트 워크 상황에 적응적으로 대응하고 단절현상을 줄일 수 있는 효과적인 RTSP 핸들링 기법을 제안 한다. 또한 캐슁 프락시의 성능을 향상시키기 위해 트래픽 기반 캐슁 기법(TSLRU)을 제안한다, TSLRU는 트래픽을 세 종류로 분류하여 캐슁하며, 교체 대상 결정시 여러 요소(traffic types, recency, frequency, object size)를 반영함으로써 캐슁 프락시의 성능을 향상 시킨다. 모의실험에서 캐슁 알고리즘은 byte hit Rate와 startup latency에서 높은 성능을 보였으며, 제안한 RTSP 핸들링 기법 역시 throughput에서 좋은 성능을 보였다.

• 한국산업보건학회지
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• 제15권1호
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• pp.1-7
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• 2005

Although the Fourier Transform Infra-Red spectrophotometric Direct on Filter(FTIR-DOF) method is a useful analytical technique for quantifying quartz content in respirable dust samples, a number of analytical problems must be taken into consideration such as, to name only a few, inhomogeneous deposition of particles, level of environmental humidity, uneven surface of the filter, and interfering minerals in the sample. This study was designed to select the most suitable wavelength and proper filter material for the method, and to investigate effects of humidity and inhomogeneous deposition of particles on the filter. Samples of respirable dust, created in a dust chamber containing standard material of quartz, were collected using a cyclone equipped with a 25mm filter as a collection medium. The results were as follows; 1. Among seven (7) commercially available filters tested for the FTIR-DOF method, the DM 800 filter showed the best analytical performance having the lowest background absorbance bands and no overlapping peaks at 799, 779, and $695cm^{-1}$. 2. The variations of absorbance due to humidity ranged from 1.0% to 3.3% for $799cm^{-1}$, 1.0% to 3.3% for $779cm^{-1}$, and 8.9%~20.9% for $695cm^{-1}$ peaks, respectively. The $699cm^{-1}$ peak was proved to be most vulnerble to environmental humidity for quantitative analysis of quartz. 3. As for effects of inhomogeneous deposition of samples, the highest variation of absorbance of 10.9% ($13.5{\mu}g$) was observed when using the 695cm-1. The variations of absorbance from the other two peaks, 799 and $779cm^{-1}$, ranged from 1.2 to 3.2%, and 1.4 to 4.1%, respectively. Therefore, the $799cm^{-1}$ peak was considered to be most reliable for quantitative analysis of quartz. The results of this study suggest that, for quantitative analysis of quartz in the respirable dust samples, use of the $799cm^{-1}$ peak can minimize the influence of environmental humidity and inhomogeneous deposition of particles on the filter. The FTIR-DOF method, if adopted for routine analysis of quartz in the respirable dust samples, could save sample preparation time and efforts substantially and also could increase analytical throughputs. Since use of the $799cm^{-1}$ peak is prone to be affected by interferences in the sample, further research on minimizing the effects is needed.

• Asian-Australasian Journal of Animal Sciences
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• 제17권2호
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• pp.221-227
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• 2004

Nutrient utilization and plasma level of minerals were studied in lactating crossbred cows fed diet supplemented from different source of minerals. Twelve crossbred cows of first to third lactation during their mid stage of lactation were distributed equally under two groups and were fed concentrate mixture, green fodder (para grass) and finger millet straw as per requirement. Cows in group I were fed concentrate mixture supplemented with 1% mineral mixture whereas cows in group II were not supplemented with mineral mixture in the concentrate mixture but were offered additional quantity of green fodder (1 kg DM/cow/day) to compensate for the requirement of minerals. Balance study conducted towards the end of 120 days of feeding experiment indicated that the total dry matter intake in both the groups did not differ significantly. The cows in group II offered additional quantity of green fodder consumed significantly (p<0.05) more of green fodder (5.11 vs. 4.51 kg /animal/day) and the cows in group I consumed significantly (p<0.01) more of finger millet straw (1.71 vs. 0.92 kg/animal/day). The digestibility of major nutrients did not differ between the groups except for ether extract which was significantly (p<0.05) lower in cows fed additional green fodder. The total daily intake of P, Cu, Fe and Co did not differ significantly in both the groups whereas significantly higher intakes of Ca, Mg, Zn and Mn were observed in cows supplemented with inorganic source of minerals. However, supplementation through both the sources could meet the mineral requirement in group I and group II. The gut absorption (%) of all the minerals was comparable between the groups except for Mg which was significantly (p<0.05) higher in cows supplemented mineral mixture. The net retention of all the minerals was significantly more in the group supplemented with inorganic source of minerals. Except for P, Mg and Co the retention as percentage of total intake was comparable for all minerals in both the groups. Irrespective of source of mineral supplementation the average monthly blood plasma mineral levels (Ca, P, Mg, Cu, Zn, Fe) were within the normal range and comparable between the groups. Lower level of Cu observed at the start of the experimental feeding in both the groups increased with the advancement of supplemental feeding. The plasma Zn and Fe content in cows of both the groups did not vary. The blood plasma level of some minerals (Ca, P, Mg and Cu) was significantly higher towards the end of experimental feeding as compared to the initial values due to the reduction in milk yield with advancement of lactation or due to supplemental effect of minerals. It could be concluded that supplementation of minerals through inorganic source is better utilized in terms of retention as compared to green fodder (para grass), which is a moderate source of most nutrients.

• Asian-Australasian Journal of Animal Sciences
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• 제16권12호
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• pp.1763-1769
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• 2003

Two experiments were conducted to examine the production and quality of cassava hay and its utilization in diets for dairy cows. In experiment I, a $2{\times}2$ Factorial arrangement in a randomized complete block design with 4 replications was carried out to determine the effects of different initial (IC) and subsequent cutting (SC) on yield and composition of cassava plant. The results revealed that cassava could produce from 4 to 7 tonne of DM and 1.2 to 1.6 tonne of CP for the first six months after planting. CP content in cassava plant ranged from 20.8 to 28.5% and was affected by different SC regimes. Condensed tannin in cassava foliage ranged from 4.9 to 5.5%. Initial cutting at 2 months with subsequent cutting at 2 month intervals was the optimal to obtain high dry matter and protein yield. In the second experiment, five crossbred Holstein-Friesian cows in mid lactation with an initial live-weight of 505${\pm}6.1kg$ and average milk yield of 10.78${\pm}1.2kg/d$ were randomly assigned in a $5{\times}5$ Latin square design to study the effects of 2 levels of CH (1 and 2 kg/hd/d) and concentrate (1 to 2 kg of milk and 1 to 3 kg of milk) on milk yield and milk composition. The results showed that cassava hay increased rumen $NH_3-N$ and milk urea nitrogen (MUN) (p<0.05). Cassava hay tended to increase milk production and 4% FCM. Milk protein increased in cows fed cassava hay (p<0.05). Moreover, cassava hay could reduce concentrate levels in dairy rations thus resulting in increased economic returns. Cassava hay can be a good source of forage to reduce concentrate supplementation and improve milk quality.

• Asian-Australasian Journal of Animal Sciences
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• 제28권3호
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• pp.351-359
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• 2015

Twelve multiparous Holstein dairy cows in mid-lactation were selected for a replicated $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement to investigate the effects of corn and soybean meal (SBM) types on rumen fermentation, N metabolism and lactation performance in dairy cows. Two types of corn (dry ground [DGC] and steam-flaked corn [SFC]) and two types of SBM (solvent-extracted and heat-treated SBM) with different ruminal degradation rates and extents were used to formulate four diets with the same basal ingredients. Each period lasted for 21 days, including 14 d for adaptation and 7 d for sample collection. Cows receiving SFC had a lower dry matter (DM) and total N intake than those fed DGC. However, the milk yield and milk protein yield were not influenced by the corn type, resulting in higher feed and N utilization efficiency in SFC-fed cows than those receiving DGC. Ruminal acetate concentrations was greater and total volatile fatty acids concentrations tended to be greater for cows receiving DGC relative to cows fed SFC, but milk fat content was not influenced by corn type. The SFC-fed cows had lower ruminal ammonia-N, less urea N in their blood and milk, and lower fecal N excretion than those on DGC. Compared with solvent-extracted SBM-fed cows, cows receiving heat-treated SBM had lower microbial protein yield in the rumen, but similar total tract apparent nutrient digestibility, N metabolism measurements, and productivity. Excessive supply of metabolizable protein in all diets may have caused the lack of difference in lactation performance between SBM types. Results of the present study indicated that increasing the energy degradability in the rumen could improve feed efficiency, and reduce environmental pollution.

• Asian-Australasian Journal of Animal Sciences
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• 제15권12호
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• pp.1754-1759
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• 2002

A study was carried out to investigate the nutritive value and utilization of hybrid sorghum and perennial grass species viz. setaria (Setaria anceps) and hybrid napier when intercropped with soybean by growing Jersey crossbred heifers. Fifteen growing crossbred heifers (Jersey${\times}$Red Sindhi) of between 7-10 months age and pre-trial average body weight of 49-50 kg were divided on the basis of weight in to three treatment groups viz. $T_1$-hybrid sorghum+soybean, $T_2$-setaria+soybean and $T_3$-hybrid napier+soybean in a completely randomized block design. Intercropped forages were harvested fresh, chaffed and mixed before they were offered to the heifers. Chemical composition of the herbage, dry matter intake (DMI), body weight gain and nutrient digestibility co-efficients were estimated. The herbage mixtures had crude protein (CP) content in the range of 11.87 to 13.86% and ether extract (EE) contents were 2.91 to 3.11%, respectively. The herbage mixtures were rich in minerals (ash). The gross energy (kcal/g DM) was higher in hybrid napier+soybean, while hybrid sorghum+soybean and setaria+soybean herbage mixtures had lower value for gross energy. The hybrid sorghum+soybean and setaria+soybean herbage mixtures had higher contents of NDF, ADF, cellulose, lignin and silica as compared to that of hybrid napier+soybean herbage mixture. The heifers fed hybrid napier+soybean herbage mixture had significantly (p<0.05) higher $DMI\;g/kg\;W^{0.75}$ ($97.41{\pm}4.34$) as compared to hybrid sorghum+soybean ($88.31{\pm}2.66$) and setaria+soybean ($79.29{\pm}1.06$) herbage mixtures. Nutrients digestibility, DCP percent, DCP intake and nitrogen balance were significantly (p<0.05) higher in the heifers fed on hybrid napier+soybean herbage mixture. There was a significant (p<0.05) difference among different herbage mixtures in TDN. The heifers on setaria+soybean herbage mixture had lower average body weight gain (g/day) than those on hybrid sorghum+soybean and hybrid napier+soybean herbage mixtures. Data obtained in this experiment demonstrated that herbage mixture of hybrid napier+soybean was better than hybrid sorghum+soybean and setaria+soybean herbage mixtures in the nutrition of growing heifers. It had highest nutritive value, better digestibility co-efficients which showed better growth rate and higher feed efficiency. In ranking, hybrid napier+soybean herbage mixture was better followed by hybrid sorghum+soybean and setaria+soybean in nutritive value in the parameters studied. For future wasteland development program in humid-sub tropics of Himachal Pradesh hybrid napier and its intercropping with soybean is recommended for general adoption because of its better adaptability and higher nutritive value.

• Asian-Australasian Journal of Animal Sciences
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• 제16권9호
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• pp.1309-1314
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• 2003

Growth performance, nutrient digestibility and changes in caecal fermentation pattern was studied on four groups of 8 grower rabbits (soviet chinchilla) each, fed on diets containing 17 to 18% CP and $10.4-11.00MJ\;DE\;kg^{-1}$ feed. The complete diets contained mulberry leaves along with other feed ingredients at 0 (LH), 15 (ML15), 30 (ML30) and 45% (ML45) levels. In LH diet ground lucerne hay was added at 15% of the diet as roughage source. The diets were uniform in other nutritional parameters except the higher amount of hemicellulose (18.7 and 16.5%) in LH and ML15 diets. The performance of grower rabbits was better (p<0.05) on LH and ML15 diets in terms of twelve weeks weight (kg), total gain (g), average daily gain (ADG) and feed efficiency (%). Different levels of mulberry leaves in the diet did not influence the dry matter intake. Digestibility of nutrients for DM, OM, CP, NDF and energy was uniform in all the diets but the digestibility of CF, ADF and cellulose was higher (p<0.01) on ML15, ML30 and ML 45 diets. The hemicellulose digestibility was significantly higher (p<0.01) on LH (44.52%) and ML15 (48.00%) compared to ML30 (33.54%) and ML 45 (39.17%) diets. The nitrogen retention (% of intake) was higher (p<0.05) in LH and ML15 diets than ML30 and ML45 diets. The caecum weight as percent of intestine weight consistently increased (p<0.05) with increasing content of mulberry leaves in diets. Total nitrogen and $NH_3$-N was higher on LH and ML15 diets. It is concluded that incorporation of mulberry leaves can replace Lucerne hay in complete rabbit feed (15% in diet). Even at higher level i.e. 30 and 45% of the diet mulberry leaves based complete feed gave promising results.

• Asian-Australasian Journal of Animal Sciences
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• 제16권8호
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• pp.1108-1117
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• 2003

In Guadeloupe small ruminants (SR) are reared for meat production under pasture conditions. Intensive rotational grazing systems (irrigated, fertilised and high stocked) allow reasonable levels of production but generate high post-grazing residues. Experiments were designed to control them. A system in which residuals were mown (RM) was tested in comparison to the control system (Residuals Remained, RR). The same design was carried out for two years with Creole goat (G) and Martinik sheep (S). An accelerated reproductive rate (3 parturitions over 2 years) was carried out. Systems were compared at three parturition seasons per year(dry, intermediate and rainy seasons). Each group was composed of 20 goats ($36.0{\pm}2.5kg$) or 20 ewes ($46.8{\pm}2.4kg$). The female body traits did not vary according to pasture management and seasons. The stocking rate averaged 1,400 kg LW/ha. The mean fertility rate for does varied significantly (p<0.05) within the kidding season, from $80.4{\pm}0.5%$ to $93.7{\pm}2.9%$ while the mean litter size was $2.30{\pm}0.07$ total kids born. No effect of pasture system was observed. Corresponding values for ewes were $83.2{\pm}12.8%$ vs. $75.6{\pm}12.5%$ (p<0.05) and $2.43{\pm}0.24$ vs. $2.03{\pm}0.29$ (p<0.01) total lambs born for SRM and SRR ewes, respectively. A seasonal effect was observed upon ewe performances. The preweaning mortality of kids and lambs averaged 16.3% and 14.4%, respectively. It was 7 and 9 percentage points more (p<0.01) for RR than for RM kids and lambs, respectively. For both species, weaning took place at an average age of $81.4{\pm}3.6days$. In Creole kids, live weight at birth and at weaning were $1.9{\pm}0.2kg$ and $8.9{\pm}0.8kg$, respectively. In the Martinik sheep, the traits averaged $2.9{\pm}0.2kg$ and $18.9{\pm}0.9kg$. For both traits in both species, significant (p<0.05) group${\times}$season interactions were recorded. The consequences of elimination of post-grazing residues varied according to the SR species, the environmental conditions and the animal physiological status. The forage characteristics were not limiting factors since forage availability in the RM systems (2,300 and 2,600 kg DM/ha, respectively) and chemical composition were at satisfactory levels (CP content averaged 12 and 10%). It is recommended to develop new grazing system which would allow the use of post-grazing residues instead of mowing the refusals.

• Asian-Australasian Journal of Animal Sciences
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• 제16권8호
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• pp.1143-1150
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• 2003

This study was conducted to investigate in vitro methane production of feed ingredients and relationship between the content of crude nutrients and methane production. Feed ingredients (total 26) were grouped as grains (5 ingredients), brans and hulls (8), oil seed meals (9) roughages (3), and animal by-product (1) from their nutrient composition and their methane production protential were measured by in vitro gas test. Among the groups, the in vitro methane productions for both 6 and 24 h incubation were highest in grains, followed by brans and hulls, oil meals and roughages, animal byproducts. Within the group of grains, methane production from wheat flour was the highest, followed by wheat, corn, tapioca, and then oat. Within the brans and hulls, soybean hull showed the highest methane production and cotton seed hull, the lowest. Methane production from oil meals was lower compared with grains and brans and hulls, and in decreasing order production from canola meal was followed by soybean meal, coconut meal, and corn germ meal (p<0.01). Three ingredients were selected and the interactions among feed ingredients were evaluated for methane production. Correlation coefficient between measured and estimated values of the combinations were 0.91. Methane production from each feed ingredient was decreased with increasing amount of crude fiber (CF), protein (CP) and ether extract (EE), whereas positive relationship was noted with the concentrations of N-free extract (NFE). The multiple regression equation (n=134) for methane production and nutrient concentrations was as follows. Methane production (ml/0.2 g DM)=(0.032${\times}$CP)-(0.057${\times}$EE)-(0.012${\times}$CF)+(0.124${\times}$NFE) (p<0.01; $R^2$=0.929). Positive relationship was noted for CP and NFE and negative relationship for CF and EE. It seems possible to predict methane production potential from nutritional composition of the ingredients for their effective application on formulating less methane emitting rations.

• Asian-Australasian Journal of Animal Sciences
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• 제28권1호
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• pp.143-150
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• 2015

The objective of this study was to evaluate the effects of different litter mixture compositions on bedding system temperature, pH and volatile fatty acid and ammonia-N ($NH_3$-N) content, and the serum physico-chemical parameters and growth indices of calves. Thirty-two Limousin calves ($280{\pm}20kg$) were randomly assigned to four groups (n = 8 for each group) according to the bedding system used: i) control with soil only (CTR); ii) mixture with 50% paddy hulls (PH), 30% saw dusts (SD), 10% peat moss (PM) and 10% corn cobs (CC) (TRT1); iii) mixture with 15% PH, 15% SD, 10% PM, 40% CC, and 20% corn stover (CS) (TRT2); iv) mixture with 30% PH, 10% PM, 40% CC, and 20% CS (TRT3). The litter material combinations of different treatments were based on the cost of bedding system materials in China. The cost of four treatments from low to high: Control$NH_3$-N level (271.83 to 894.72 mg/kg) was lowest for TRT1 (p<0.0001) and highest for TRT2 (p<0.0001). The acetate, propionate and butyrate levels were highest for the control group (p<0.0001). In all the groups, the pH value (6.90 to 9.09) increased at the beginning and later remained stable at below 9.09. The temperature of deep litter increased at the first week and reached the maximum ($42.1^{\circ}C$) on day 38. 3,5,3'-Triiodothyronine ($T_3$) levels in the TRT1 group animals (p<0.0001) were lower than those in the control and TRT2 animals. 3,5,3',5'-Tetraiodothyronine ($T_4$) in the TRT1 group (p = 0.006) was lower than that in the other treatment groups. Cortisol (COR) in the control and TRT1 group was lower (p<0.0001) than that in the TRT2 and TRT3 groups. Corticosterone (CORt) in the control group was higher (p<0.0001) than that in the treatment groups. The findings indicate that the deep litter bedding systems provided better conditions for animal health and growth performance compared with the control system. Furthermore, the litter composition of TRT1 was found to be optimal among the three treatment groups.