This study presents probabilistic-based damage identification technique for highlighting damage in metallic structures. This technique utilizes distributed piezoelectric transducers to generate and monitor the ultrasonic Lamb wave with narrowband frequency. Diagnostic signals were used to define the scatter signals of different paths. The energy of scatter signals till different times were calculated by taking root mean square of the scatter signals. For each pair of parallel paths an error function based on the energy of scatter signals is introduced. The resultant error function then is used to estimate the probability of the presence of damage in the monitoring area. The presented method with an autofocusing feature is applied to aluminum plates for method verification. The results identified using both simulation and experimental Lamb wave signals at different central frequencies agreed well with the actual situations, demonstrating the potential of the presented algorithm for identification of damage in metallic structures. An obvious merit of the presented technique is that in addition to damages located inside the region between transducers; those who are outside this region can also be monitored without any interpretation of signals. This novelty qualifies this method for online structural health monitoring.
Journal of the Korean Society of Food Science and Nutrition
/
v.30
no.1
/
pp.75-79
/
2001
Quality changes in sausage stuffed into irradiated natural pork and lamb intestine were studied. Total aerobic bacteria of the sausage prepared with irradiated natural pork and lamb casing were significantly lower than those of nonirradiated casing and the $D_{10}$ value of those sausages were 1.71 and 1.58 kGy, respectively. The sausages in pork intestine vacuum-packaged and stored in a $4^{\circ}C$ refrigerator showed negligible change in the 2-thiobarbituric acid reactive substances (TBARS) value during storage except for 10-day when the TBARS value was higher than other storage days. Total working force for shear value of the sausages were lower with both irradiated casings but sensory evaluation showed no difference between treatments. As a results, the gamma irradiation was effective for sanitizing the natural pork and lamb casings, thereby preparing high quality sausages.
Journal of the Korean Society for Nondestructive Testing
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v.32
no.1
/
pp.47-55
/
2012
A structural health monitoring technique for locating impact position in a plate structure is presented in this paper. The method employs a single sensor and spatial focusing of time reversal (TR) acoustics. We first examine the TR focusing effect at the impact position and its surroundings through simulation and experiment. The imaging results of impact points show that the impact source location can be accurately estimated in any position of the plate. Compared to existing techniques for locating impact or acoustic emission source, the proposed method has the benefits of using a single sensor and not requiring material properties and geometry of structures. Furthermore, it does not depend on a particular mode of dispersive Lamb waves that is frequently used in other ultrasonic testings of plate-like structures.
The animal production sector in Jordan is characterized by shortages of locally produced feedstuffs derived from rangeland, forage plants or from human food crops as by products. This is exacerbated by insufficient rainfall, overgrazing, early grazing and high stocking rate. Thus, subject to these constraints, other technological improvements are highly desirable to meet the needs of crop growth and animal production. Alternative adapted technologies are also desirable in order to meet the increased demand for red meat in relation to population growth along with the changes in the price subsidy for feedstuff. The technologies are those, which have been introduced to the animal production sector, obtained in agricultural research stations besides on-farm demonstrations. They include technologies suited for increasing birth and twining rates, synchronizing the mating period, introducing the early weaning method, and animal feed and sheep production. Economic assessments conducted in this study demonstrate promising results of hormonal and nutritional practices in improving production efficiency of Awassi sheep in Jordan. Jordanian published data between 1991 and 1998 were used. The examined practices were: 1) use of PMSG in estrus synchronization in ewes, 2) introduction of early lamb weaning program, 3) supplementation with $AD_3E$ for ewes and 4) the use of agro-industrial feed block as a feed supplement for grazing lambs. Production data were then subjected to partial budgeting for economical evaluation. The use of PMSG outperformed the control groups in fertility and net returns per ewe by US$ 8.36/ewe. The early weaning of lambs increased the net returns by US$ 3.90/lamb. The injection with vitamin $AD_3E$ showed an average additional net return of US$ 5.66/ewe. Feeding agriculture by-product blocks improved weight gain in the feed block groups and resulted in additional net returns of US$ 3.5/lamb. The economic viability and reproductive performance indicators demonstrate that efforts should be undertaken to disseminate these new practices in the development program.
Objective: This study aimed to investigate the effect of dietary supplementation with Allium mongolicum Regel extracts on the growth performance, carcass characteristics, fat color, and concentrations of three branched-chain fatty acids related to flavor in ram lambs. Methods: Sixty 3-month-old, male, small-tailed Han sheep were selected and randomly allocated into four groups in a randomized block design. Four feeding treatments were used: i) a basal diet without supplementation as the control group (CK); ii) the basal diet supplemented with 10 g/lamb/d Allium mongolicum Regel powder as the AMR group; iii) the basal diet supplemented with 3.4 g/lamb/d Allium mongolicum Regel water extract as the AWE group; and iv) the basal diet supplemented with 2.8 g/lamb/d Allium mongolicum Regel ethanol extract as the AFE group. Results: The results demonstrated that the dry matter intake was lower for the AFE group than that in other groups (p = 0.001). The feed conversion ratio was greater for the AFE than that in other groups (p = 0.039). Dietary supplementation with Allium mongolicum Regel powder and its extracts decreased the concentrations of 4-methyloctanoic acid (MOA) (p<0.001), 4-ethyloctanoic acid (EOA) (p<0.001), and 4-methylnonanoic acid (MNA) (p = 0.044) in perirenal adipose tissue compared to those observed in the CK lambs. Dietary supplementation with Allium mongolicum Regel powder and its extracts decreased the concentrations of MOA (p<0.001) and EOA (p<0.001) in dorsal subcutaneous adipose tissue compared to those in the CK lambs. The concentrations of MOA (p<0.001) and EOA (p = 0.002) in omental adipose tissue were significantly affected by treatment, although there was a tendency for lower MNA (p = 0.062) in AMR, AWE, and AFE lambs than that in CK lambs. Conclusion: This study demonstrated that Allium mongolicum Regel and its extracts could significantly promote feed efficiency, although dry matter intake decreased and could decrease the MOA and EOA concentrations related to characteristic flavor and odor of body fat in lambs, except for tail adipose tissue.
KSCE Journal of Civil and Environmental Engineering Research
/
v.29
no.5A
/
pp.421-431
/
2009
This paper is the study on the verification of structural health monitoring (SHM) algorithm based on the ultrasonic guided wave. An active inspection system using Lamb wave (LW) for SHM was considered. The basic study about the application of this algorithm was performed for detecting the circular notch defect in steel plate. LW testing technique, pitch-catch method, was used for interpretation of circular notch defect with depth of 50% of plate thickness and 7 mm width. Damage characterization takes place by comparing $S_0$ mode sensor signals collected before and after the damage event. By subtracting the signals of both conditions from each other, a scatter signal is produced which can be used for damage localization. The continuous Gabor wavelet transform is used to attain the time between the arrivals of the scatter and sensor signals. A new practical damage monitoring algorithm, based on damage monitoring polygon and pitch-catch method, has been proposed and verified with good accuracy. The possible damage location can be estimated by the average on calculated location points and the damage extent by the standard deviation.
The present study evaluated the effect of controlled ryegrass-white clover herbage availability from day 128 until day 142 of pregnancy in comparison to unrestricted availability, on the performance of twin-bearing ewes of varying body condition score (BCS; 2.0, 2.5, or 3.0) and their lambs. It was hypothesised that under conditions of controlled herbage availability, the performance of lambs born to ewes with a greater BCS would be greater than those born to ewes with a lower BCS. During the period that the nutritional regimens were imposed, the pre- and post-grazing herbage masses of the Control regimen ($1,070{\pm}69$ and $801{\pm}30$ kg dry matter [DM]/ha) were lower than the ad libitum regimen ($1,784{\pm}69$ and $1,333{\pm}33kg\;DM/ha$; p<0.05). The average herbage masses during lactation were $1,410{\pm}31kg\;DM/ha$. Nutritional regimen had no effect on ewe live weight, BCS and back fat depth or on lamb live weight, indices of colostrum uptake, maximal heat production, total litter weight weaned or survival to weaning (p>0.05). The difference in ewe BCSs and back fats observed among body condition groups was maintained throughout pregnancy (p<0.05). At weaning, ewes from the BCS2.0 group had lower BCS and live weight ($2.4{\pm}0.2$, $74.3{\pm}2.6kg$) than both the BCS2.5 ($2.6{\pm}0.2$, $78.6{\pm}2.4kg$) and BCS3.0 ewes ($2.7{\pm}0.2$, $79.0{\pm}2.6kg$; p<0.05), which did not differ (p>0.05). Ewe BCS group had no effect on lamb live weight at birth or weaning or on maximal heat production (p>0.05). Serum gamma glutamyl transferase concentrations of lambs born to BCS3.0 ewes were higher within 36 hours of birth than lambs born to BCS2.0 ewes and BCS2.5 ewes ($51.8{\pm}1.9$ vs $46.5{\pm}1.9$ and $45.6{\pm}1.9IU/mL$, respectively [p<0.05]). There was, however, no effect of ewe body condition on lamb plasma glucose concentration (p>0.05). Lamb survival was the only lamb parameter that showed an interaction between ewe nutritional regimen and ewe BCS whereby survival of lambs born to BCS2.5 and BCS3.0 ewes differed but only within the Control nutritional regimen ewes (p<0.05). These results indicate farmers can provide twin-bearing ewes with pre- and post-grazing ryegrass-white clover herbage covers of approximately 1,100 and 800 kg DM/ha in late pregnancy, provided that herbage covers are 1400 in lactation, without affecting lamb performance to weaning. The present results also indicate that under these grazing conditions, there is little difference in ewe performance within the BCS range of 2.0 to 3.0 and therefore they do not need to be managed separately.
Lycopene, a red non-provitamin A carotenoid, mainly presenting in tomato and tomato byproducts, has the highest antioxidant activity among carotenoids because of its high number of conjugated double bonds. The objective of this study was to investigate the effect of lycopene supplementation in the diet on plasma lipid profile, lipid peroxidation and antioxidant defense system in feedlot lamb. Twenty-eight Bamei male lambs (90 days old) were divided into four groups and fed a basal diet (LP0, 40:60 roughage: concentrate) or the basal diet supplemented with 50, 100, and 200 mg/kg lycopene. After 120 days of feeding, all lambs were slaughtered and sampled. Dietary lycopene supplementation significantly reduced the levels of plasma total cholesterol (p<0.05, linearly), total triglycerides (TG, p<0.05) and low-density lipoprotein cholesterol (LDL-C, p<0.05), as well as atherogenic index (p<0.001), whereas no change was observed in high-density lipoprotein cholesterol (p>0.05). The levels of TG (p<0.001) and LDL-C (p<0.001) were decreased with the feeding time extension, and both showed a linear trend (p<0.01). Malondialdehyde level in plasma and liver decreased linearly with the increase of lycopene inclusion levels (p<0.01). Dietary lycopene intake linearly increased the plasma antioxidant vitamin E level (p<0.001), total antioxidant capacity (T-AOC, p<0.05), and activities of catalase (CAT, p<0.01), glutathione peroxidase (GSH-Px, p<0.05) and superoxide dismutase (SOD, p<0.05). The plasma T-AOC and activities of GSH-Px and SOD decreased with the extension of the feeding time. In liver, dietary lycopene inclusion showed similar antioxidant effects with respect to activities of CAT (p<0.05, linearly) and SOD (p<0.001, linearly). Therefore, it was concluded that lycopene supplementation improved the antioxidant status of the lamb and optimized the plasma lipid profile, the dosage of 200 mg lycopene/kg feed might be desirable for growing lambs to prevent environment stress and maintain normal physiological metabolism.
Lee, H.J.;Lee, S.C.;Kim, D.W.;Park, J.G.;Han, In K.
Asian-Australasian Journal of Animal Sciences
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v.13
no.2
/
pp.155-160
/
2000
In order to understand the effects of sex or age on cellular characteristics of adipocytes from Hanwoo and sheep, samples were obtained from omental, subcutaneous, intermuscular and intramuscular adipose tissue depots of bulls, steers, heifers and cows in Hanwoo, and perirenal, omental and subcutaneous adipose tissues of fetal lambs, suckling lambs and wethers in sheep. In case of Hanwoo, mean diameter, surface area and volume of adipocytes from each depot were obtained by multisizer II (Coulter Co., UK). Osmium-fixed adipocytes were sized and counted using $560{\mu}m$ aperture. For samples obtained from sheep, cellularity was measured by using microscope and MCV program of Texas Instrument. Bulls had less subcutaneous and kidney fat than steers even though their slaughter and carcass weight were heavier. The amounts of fat from cows were greater in subcutaneous, kidney and internal organs than heifers. Steers had larger adipocytes in subcutaneous, intermuscular and intramuscular adipose tissues than bulls, although the differences were significant only for the subcutaneous adipose tissue depots. Adipocytes appeared to be largest in omental and smallest in intramuscular adipose tissue, although there were no significant differences among tissues. In a comparison of heifers and cows, significant site effects (p<0.05) were shown in adipocyte diameter, surface area and volume, and adipocyte appeared to be largest in omental tissue. Statistical difference (p<0.05) was only shown in cell volume of intramuscular tissue which was higher in cow than heifer. Intramuscular adipose tissue tended to have relatively greater numbers of cells per gram tissue and reflect lesser maturity of intramuscular adipose tissue relative to other adipose tissues. In sheep, regardless of adipose tissue depots, wethers had the greater adipocyte diameters than those at any other growth stage of sheep. Within adipose depots, the ranking of cell size was the greatest in the omental tissue of wether and the lowest in the renal and subcutaneous adipose tissue depots of fetal lamb. The cell size of adipocyte became larger with age, especially from fetal to suckling lamb due to a rapid hypertrophy of both perirenal and subcutaneous adipocytes during the suckling period.
Gronqvist, Gabriella V.;Corner-Thomas, Rene A.;Kenyon, Paul R.;Stafford, Kevin J.;Morris, Stephen T.;Hickson, Rebecca E.
Asian-Australasian Journal of Animal Sciences
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v.31
no.12
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pp.1991-2000
/
2018
Objective: Triplet-born lambs are less likely to survive to weaning than twin-born or single-born lambs. Appropriate ewe-lamb bonding behaviours and lamb vigour behaviours are necessary for survival of lambs. The aim of this experiment was to determine whether maternal nutrition during late pregnancy influenced behaviour of the ewe and her lambs soon after birth, and to determine whether mid-pregnancy body condition score (BCS) influenced any behavioural response. Methods: The experiments included ewes that were in BCS 2.0, 2.5, or 3.0 in mid-pregnancy and were fed either ad libitum or to pregnancy-maintenance requirements in late-pregnancy (day 115 until 136 in experiment one, and day 128 until 141 in experiment two). The time taken for lambs to stand, contact dam, suck from dam and follow dam was recorded three to 18 h after birth. The number of high- and low-pitched bleats emitted by the ewe and lambs was recorded, along with maternal behaviour score (MBS) of the ewe. Lambs in experiment two underwent a maternal-recognition test at 12 or 24 h. Results: There were significant effects of feeding treatment on bleating behaviour of ewes and lambs, but these were inconsistent among BCS groups and between experiments. Lamb vigour behaviours were not affected by feeding treatment. In experiment one, there was no effect of feeding treatment or BCS on MBS, but in experiment two, ewes in BCS3 in mid-pregnancy had greater MBS than ewes in BCS2 in mid-pregnancy (MBS 3.1/5 vs MBS 2.1/5; p<0.05). Conclusion: Given there were no repeatable effects on behaviour of ewes and lambs, ad libitum feeding rather than feeding for pregnancy-maintenance requirements cannot be used to improve behaviours soon after birth of triplet-bearing ewes in BCS 2-3 and their lambs in extensive pastoral conditions.
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