• Asian-Australasian Journal of Animal Sciences
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• v.13 no.12
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• pp.1659-1666
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• 2000

Two experiments were conducted to determine the effects of Leucaena leucocephala (leucaena) and Gliricidia sepium (gliricidia) supplementation on intake, digestion, outflow rates, microbial protein yield and live-weight changes in sheep fed with ammoniated rice straw (ARS). In experiment 1, three rumen cannulated Japanese Corriedale wether (mean body weight of 35.6 kg) in $3{\times}3$ Latin Square Design were used. Animals were fed ad libitum ARS alone, or supplemented with 200 g of either leucaena or gliricidia. In experiment 2, twenty-four growing native Philippine sheep with average body weight of $13.5{\pm}0.25kg$ were used in a completely randomized design (CRD) and offered similar diets to those of experiment 1. Supplementation increased total dry matter intake and nutrient digestibility except for fiber (p<0.05) without affecting ARS consumption. Nitrogen balance revealed that absorbed and retained N was significantly higher in leucaena and gliricidia. The significant improvement in N utilization and more digestible OM intake brought about by the inclusion of leucaena and gliricidia to ARS resulted in increased (p<0.05) microbial N yield. Efficiency of microbial N supply in supplemented group was not significantly different, but higher (p<0.05) than the 24.92 g N/kg DOMR for ARS group. Liquid outflow rate was 7.8 and 6.8 %/h, while the solid phase of rumen digesta was 4.4 and 3.8 %/h for the leucaena and gliricidia group respectively, which were significantly higher than 5.30 and 2.50 %/h in the control diet. The increase in total DMI resulted to higher (p<0.01) growth performance and efficient feed utilization. Average daily gain (ADG) was 19.3, 34.6 and 33.9 g/d for the ARS, leucaena and gliricidia respectively. It is therefore concluded that addition of leucaena and gliricidia to ARS in could increase nutrient intake and digestibility, subsequently improving N utilization and livestock performance.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.11
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• pp.1995-2005
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• 2000

The use of heterotrophic denitrification as an alternative method for supplying alkalinity during sulfur-utilizing autotrophic denitrification was evaluated by examining the effects of external carbon source (both type and concentration) and HRT on denitrification efficiency. Concentrations of $NO_3{^-}-N$ and $COD_{Cr}$ of nitrified landfill leachate used for experiment were 700-900mg/L and 900-2500mg/L. respectively, All experiment was conducted with sulfur packed bed reactors (SPBRs) which were operated at $35^{\circ}C$. The fraction of $NO_3{^-}-N$ removed by heterotrophic denitrification ($HDNR_{fraction}$) to balance the alkalinity consumption by autotrophic denitrification varied with the type of external carbon source. When methanol and sodium acetate was added at theoretical HDNRfraction value. 100% denitrification was achieved without alkalinity addition. However, glucose and molasses require $HDNR_{fraction}$ value greater than theoretical value for complete denitrification. The EBCT and volumetric loading rate at which 100% denitrification efficiency could be achieved were 6.76 h and $2.84kg-NO_3{^-}-N/m^3{\cdot}d$, respectively, based on the fact that 100% denitrification occurred within the bottom 11.5 cm layer of the SPBR. The maximum nitrogen removal rate occurred with 89% removal efficiency at loading rate of $5.05kg-NO_3{^-}-N/m^3{\cdot}d$. However, at short EBCT, clogging of SPBR was observed with excess growth of heterotrophic denitrifiers. This problem may be eliminated by back washing or by separating of heterotrophic denitrification from sulfur-utilizing denitrification.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.384-388
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• 2003

Twenty yearling lambs of Southeast Nigeria dwarf, liveweight ($18{\pm}1.9 kg$) were grouped into 5 treatments. Dry brewer's grain was substituted for maize offal in the experiment diets namely A to E at 0%, 15%, 30%, 45% and 60% respectively, as supplement to low quality, dry season cassava leaf top and Andropogan gayanus hay at 1:1 ratio that lasted for 56 days. After which 5 of the lambs (average bodyweight=$24.3{\pm}1.5kg$) were transferred to metabolism crates to determine the digestibility and nitrogen/protein balance studies. While the mean group intakes were (945.9, 996.1, 1,040.5, 1,148.5 and 1,037.7 g conc. DM/day), the growth rates were (115.1, 124.1, 152.5, 168.5 and 123.1 g liveweight gain/day), respectively. There was a recorded decline in both intake (p>0.05) and growth rate (p<0.05) as the level of dry brewer's grain was increased beyond 45% of the supplement. Similar trend was observed on the protein and organic matter efficiency ratios (p>0.05) together with the organic matter intake. The urine nitrogen output was also significant (p>0.05). The work further revealed that, at a certain critical level of intake, dry brewer's grain is able to support growth rates measurable to or better than those noted when feeding maize offal to lambs, and went on to prove dry brewer's grain as an attractive supplementary feed for the drier months of the year, in the Southeast of Nigeria.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.5
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• pp.655-659
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• 2003

Forty eight lambs (24 each of Malpura and Mutton synthetic breeds) were weaned at 90 days of age and divided into two groups. One group of 12 lambs from each of the two breeds was maintained on low energy (52% TDN) and the other group of 12 on high energy (58% TDN) feedlot ration until 6 of the lambs attained 20 kg and the other 6 attained 25 kg live weight in each of the two groups. Daily feed intake and weekly body weights were recorded. Conventional metabolism trials were conducted on the two breeds and the two rations. The growth rate was found to be higher for lambs on high energy ration (p<0.01). The growth rate was also higher for higher target weight groups (p<0.01). The breed did not significantly affect the live weight gains. Mutton synthetic lambs required less number of days to reach 20 kg live weights but took more time to reach 25 kg target weight as compared to Malpura lambs (p<0.01). The lambs of both the breeds reached 25 kg live weight earlier on high energy than those on low energy ration (p<0.01). The dry matter intake, irrespective of breed, was significantly higher (4.57% or 93.4 g per kgW$^{0.75}$) on low energy than that on high energy ration (4.20% or 87.2 g per kg W$^{0.75}$). The digestibility coefficients of all the nutrients excepting crude fibre were significantly higher on high energy diet irrespective of the breed. Lambs on low energy ration, however, digested the crude fibre more than those on the high energy ration (p<0.05). Although there were no significant differences in the intakes of nitrogen, calcium and phosphorus, the balance of nitrogen was higher on high energy ration. The DCP and TDN values were 9.70 and 52.76% for low energy and 9.89 and 57.68 % for high energy ration, respectively. The dressing percentages on live weight basis were 50.2 on low and 51.6 on high energy ration, 50.5 at 20kg and 51.3 at 25 kg slaughter weight and 51.0 in Malpura and 50.8 in Mutton synthetic lambs, respectively. The percent of bones in the carcass was higher on low energy ration in Mutton synthetic lambs at 20 kg slaughter weight than others. It was concluded that the performance of the lambs in respect of mutton production was significantly better on high energy ration fed upto 25 kg slaughter weight with no or little breed differences.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.7
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• pp.1873-1893
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• 2023

The development of lightweight, low energy and small-sized sensors incorporated with the wireless networks has brought about a phenomenal growth of Wireless Sensor Networks (WSNs) in its different fields of applications. Moreover, the routing of data is crucial in a wide number of critical applications that includes ecosystem monitoring, military and disaster management. However, the time-delay, energy imbalance and minimized network lifetime are considered as the key problems faced during the process of data transmission. Furthermore, only when the functionality of cluster head selection is available in WSNs, it is possible to improve energy and network lifetime. Besides that, the task of cluster head selection is regarded as an NP-hard optimization problem that can be effectively modelled using hybrid metaheuristic approaches. Due to this reason, an Improved Coyote Optimization Algorithm-based Clustering Technique (ICOACT) is proposed for extending the lifetime for making efficient choices for cluster heads while maintaining a consistent balance between exploitation and exploration. The issue of premature convergence and its tendency of being trapped into the local optima in the Improved Coyote Optimization Algorithm (ICOA) through the selection of center solution is used for replacing the best solution in the search space during the clustering functionality. The simulation results of the proposed ICOACT confirmed its efficiency by increasing the number of alive nodes, the total number of clusters formed with the least amount of end-to-end delay and mean packet loss rate.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.4
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• pp.337-343
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• 1998

In a feeding trial, Jamunapari male kids (18) of about 4 months age were equally divided into two groups of nine animals each. Goats in the experimental group were fed sun-dried pelleted Leucaena leucocephala leaves and those in the control group were offered a conventional diet without Leucaena leaves as per Kearl (1982) recommendations for a period of 6 months. Daily dry matter intake DMI/100 kg BW was $3.13{\pm}0.04kg$ in the Leucaena group and $3.30{\pm}0.05kg$ in the control. There were significant (p < 0.01) differences in the apparent digestibilities of DM, OM, CP, EE, CF and NFE being lower in the Leucaena group. Contents of digestible crude protein (DCP) and total digestible nutrients (TDN) were 11.40 and 52.20%, respectively, in the Leucaena group and 14.04 and 66.10%, respectively in the control. The nitrogen in the Leucaena group was not well utilized as compared to the control, though kids were in positive nitrogen balance in both the groups. The average daily weight gain of kids on pelleted Leucaena was $29.95{\pm}2.60g$ as against $42.09{\pm}3.24g$ observed in the control. The mean DMI/kg LW gain was significantly (p < 0.01) higher in the Leucaena group ($14.70{\pm}0.78kg$) as compared to the control ($11.55{\pm}0.46kg$). The Hb, BUN, SGOT and SGPT concentrations were statistically similar in both the groups. Histopathological examination of thyroid gland of goats sacrificed at the end of experiment did not reveal any signs of colloidal goitre associated with mimosine toxicity. No significant pathological alterations were observed in vital organs irrespective of dietary treatment. Sundried, pelleted Leucaena foliage appears to be a promising potential feed for growing goats without any significant deleterious effect.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.3
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• pp.231-238
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• 1986

This field experiment was undertaken to assess the effects of three levels of inclination ($10^{\circ}$, $20^{\circ}$ and $30^{\circ}$) and four rates of $N-P_2O_5-K_2O$ (0-0-0, 14-10-10, 28-25-25, and 42-40-40 kg/10a) on the hilly pasture concerning to establishment, forage yield and quality, and botanical composition in the mixed grass-clover sward set up on a new reclaimed woodland by an oversowing method. This part was concerned with the concentration and mutual balance of mineral nutrients in relation to grass tetany hazard. The results obtained were summarized as follows: 1. Concentration of exchangeable Mg, relative proportions of Mg to CEC, K, and Ca in soil were considerably below the critical level for good forage growth and prevention of grass tetany. These properties were rather worsened by increasing the inclination grade and the NPK rate. 2. Compared with the critical level for the likelihood of tetany (Mg < 0.2%, K > 2.5%, and K/(Ca+Mg) equivalent ratio > 2.2 in forages in DM basis), mean concentration of Mg in mixed forages turned out to range from 0.09 to 0.14%. 2.6% of K concentration and 2.5 of K/(Ca+Mg) equivalent ratio were shown to be at a normal NPK rate. The likelihood of grass tetany was generally enhanced by increasing the inclination grade and the NPK rate. 3. The increasing of the inclination grade and NPK rate rather aggravated the low Mg concentration and unbalanced mutual ratios of mineral nutrients, from which resulted the grass tetany hazard and the depression of forage growth. To prevent these two resulted factors, Mg fertilization on grassland and/or extra Mg supplement to dairy cattle needed to be carried out. 4. The Ca/P ratios in the mixed forages ranging from 1.0 to 2.0 were reduced by the increased rate of NPK, whereas the difference due to inclination grade was yet to be recognized.

• Magazine of the Korean Society of Agricultural Engineers
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• v.19 no.1
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• pp.4279-4295
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• 1977

Two types of model were established in order to product the soil moisture content by which information on irrigation could be obtained. Model-I was to represent the soil moisture depletion and was established based on the concept of water balance in a given soil profile. Model-II was a mathematical model derived from the analysis of soil moisture variation curves which were drawn from the observed data. In establishing the Model-I, the method and procedure to estimate parameters for the determination of the variables such as evapotranspirations, effective rainfalls, and drainage amounts were discussed. Empirical equations representing soil moisture variation curves were derived from the observed data as the Model-II. The procedure for forecasting timing and amounts of irrigation under the given soil moisture content was discussed. The established models were checked by comparing the observed data with those predicted by the model. Obtained results are summarized as follows: 1. As a water balance model of a given soil profile, the soil moisture depletion D, could be represented as the equation(2). 2. Among the various empirical formulae for potential evapotranspiration (Etp), Penman's formula was best fit to the data observed with the evaporation pans and tanks in Suweon area. High degree of positive correlation between Penman's predicted data and observed data with a large evaporation pan was confirmed. and the regression enquation was Y=0.7436X+17.2918, where Y represents evaporation rate from large evaporation pan, in mm/10days, and X represents potential evapotranspiration rate estimated by use of Penman's formula. 3. Evapotranspiration, Et, could be estimated from the potential evapotranspiration, Etp, by introducing the consumptive use coefficient, Kc, which was repre sensed by the following relationship: Kc=Kco$.$Ka＋Ks‥‥‥(Eq. 6) where Kco : crop coefficient Ka : coefficient depending on the soil moisture content Ks : correction coefficient a. Crop coefficient. Kco. Crop coefficients of barley, bean, and wheat for each growth stage were found to be dependent on the crop. b. Coefficient depending on the soil moisture content, Ka. The values of Ka for clay loam, sandy loam, and loamy sand revealed a similar tendency to those of Pierce type. c. Correction coefficent, Ks. Following relationships were established to estimate Ks values: Ks=Kc-Kco$.$Ka, where Ks=0 if Kc,=Kco$.$K0$\geq$1.0, otherwise Ks=1-Kco$.$Ka 4. Effective rainfall, Re, was estimated by using following relationships : Re=D, if R-D$\geq$0, otherwise, Re=R 5. The difference between rainfall, R, and the soil moisture depletion D, was taken as drainage amount, Wd. {{{{D= SUM from { {i }=1} to n (Et-Re-I+Wd)}}}} if Wd=0, otherwise, {{{{D= SUM from { {i }=tf} to n (Et-Re-I+Wd)}}}} where tf=2∼3 days. 6. The curves and their corresponding empirical equations for the variation of soil moisture depending on the soil types, soil depths are shown on Fig. 8 (a,b.c,d). The general mathematical model on soil moisture variation depending on seasons, weather, and soil types were as follow: {{{{SMC= SUM ( { C}_{i }Exp( { - lambda }_{i } { t}_{i } )+ { Re}_{i } - { Excess}_{i } )}}}} where SMC : soil moisture content C : constant depending on an initial soil moisture content $\lambda$ : constant depending on season t : time Re : effective rainfall Excess : drainage and excess soil moisture other than drainage. The values of $\lambda$ are shown on Table 1. 7. The timing and amount of irrigation could be predicted by the equation (9-a) and (9-b,c), respectively. 8. Under the given conditions, the model for scheduling irrigation was completed. Fig. 9 show computer flow charts of the model. a. To estimate a potential evapotranspiration, Penman's equation was used if a complete observed meteorological data were available, and Jensen-Haise's equation was used if a forecasted meteorological data were available, However none of the observed or forecasted data were available, the equation (15) was used. b. As an input time data, a crop carlender was used, which was made based on the time when the growth stage of the crop shows it's maximum effective leaf coverage. 9. For the purpose of validation of the models, observed data of soil moiture content under various conditions from May, 1975 to July, 1975 were compared to the data predicted by Model-I and Model-II. Model-I shows the relative error of 4.6 to 14.3 percent which is an acceptable range of error in view of engineering purpose. Model-II shows 3 to 16.7 percent of relative error which is a little larger than the one from the Model-I. 10. Comparing two models, the followings are concluded: Model-I established on the theoretical background can predict with a satisfiable reliability far practical use provided that forecasted meteorological data are available. On the other hand, Model-II was superior to Model-I in it's simplicity, but it needs long period and wide scope of observed data to predict acceptable soil moisture content. Further studies are needed on the Model-II to make it acceptable in practical use.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.80-90
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• 2004

Three experiments were performed to test the assumption that imbalanced dietary amino acid mixtures must lead to increased heat production (HP). The first experiment was based on diets formulated to have a wide range of crude protein (CP) concentrations but a fixed concentration of lysine, formulated to be the first-limiting amino acid. In the second (converse) experiment, lysine concentration was varied over a wide range while CP content was kept constant. To prevent the masking of dietary effects by thermoregulatory demands, the third experiment was performed at 30 $^{\circ}C$ with the diets similar to the diets used in the second experiment. The detailed relationships among amino acid balance, nitrogen (N) metabolism and energy (E) metabolism were investigated in a computer-controlled chamber calorimetry system. The results of experiments were compared with the predictions of a computerised simulation model of E metabolism. In experiment 1. with constant lysine and varying CP, there was a 75 % increase in N intake as CP concentration increased. This led to a 150 % increase in N excretion. with no significant change in HP. Simulated HP agreed with the empirically determined results in not showing a trend with dietary CP. In experiment 2, with varying lysine but constant CP, there was a 3-fold difference in daily weight gain between the lowest and highest lysine diets. HP per bird increased significantly with dietary lysine concentration. There was still an effect when HP was adjusted for body weight differences, but it failed to maintain statistical significance. Simulated HP results agreed in showing little effect of varying lysine concentration and growth rate on HP. Based on the results of these two experiments, the third experiment was designed to test the response of birds to dietary lysine in high ambient temperature. In experiment 3 which performed at high ambient temperature (30 $^{\circ}C$), HP per bird increased significantly with dietary lysine content, whether or not adjusted for body-weight. The trend was greater than in the previous experiment (20 $^{\circ}C$).

• Atmosphere
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• v.31 no.5
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• pp.593-606
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• 2021

The Korea Meteorological Administration/National Institute of Meteorological Sciences (KMA/NIMS) has monitored atmospheric CO₂ at Anmyeondo (AMY) World Meteorological Organization (WMO) Global Atmosphere Watch Programme (GAW) regional station since 1999, and expanded its observations at Jeju Gosan Suwolbong station (JGS) in the South and at Ulleungdo-Dokdo stations in the East (ULD and DOK) since 2012. Due to a recent WMO CO₂ scale update and a new filter (NIMS) to select baseline levels at each station, the 22 years of CO₂ data are recalculated. After correction for the new CO₂ scale, we confirmed that those corrected records are reasonable within the compatibility goal (±0.1 ppm of CO₂) between KMA/NIMS and National Oceanic and Atmosphereic Administration (NOAA) flask-air measurements with the new scale. With the new NIMS filter, CO₂ baseline levels are now more representative of the large-scale background compared to previous values, which contained large CO₂ enhancements. Atmospheric CO₂ observed in South Korea is 4 to 8 ppm greater than the global average while the amplitude of seasonal variation is similar (10~13 ppm) to the amplitude averaged over a comparable latitude zone (30°N-60°N). Variations in CO₂ growth rate are also similar, increasing and decreasing similar to global values, as it reflects the net balance between terrestrial respiration and photosynthesis. In 2020, atmospheric CO₂ continued increasing despite the COVID-19 pandemic. Even though fossil emission was reduced (around -7% globally), we still emitted large amounts of anthropogenic CO₂. Overall, since CO₂ has large natural variations and its source was derived from not only fossil fuel but also biomass burning, the small fossil emission reduction could not affect the atmospheric level directly.