• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4418-4425
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• 2012

The demand on applying the performance-based logistics (PBL) in the operational phase of the weapon systems development is increasing these days. Therefore, the enhancement of the PBL concept and process needs to be done. This is the objective of the paper. As a method of approach, a modeling method is adopted to cover the whole life cycle of the weapon systems development from the concept development to the operation. The modeling results for the PBL process yield an useful suggestion for improvement. Also, by analyzing the interrelationship model between the PBL process and the integrated logistics support (ILS) procedure, it is possible to take advantage of the PBL concept in the ILS elements development, which is usually carried out from the beginning of the development phase, a lot earlier than the operational phase. Note that the PBL concept has been restrictively applied in only the supply support among many ILS elements up until now. However, the results obtained in the paper can make it also possible to consider the availability, reliability, logistics support, cost and so on from the early phase of the weapon systems development.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.12
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• pp.1914-1922
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• 2004

This paper provides a comprehensive study of optimum design of a helicopter tailrotor driveshaft made of the flexible matrix composites (FMCs). Since the driveshaft transmits power while subjected to large bending deformation due to aerodynamic loadings, the FMCs can be ideal for enhancing the drivetrain performance by absorbing the lateral deformation without shaft segmentation. However, the increased lateral flexibility and high internal damping of the FMCs may induce whirling instability at supercritical operating conditions. Thus, the purpose of optimization in this paper is to find a set of tailored FMC parameters that compromise between the lateral flexibility and the whirling stability while satisfying several criteria such as torsional buckling safety and the maximum shaft temperature at steadystate conditions. At first, the drivetrain was modeled based on the finite element method and the classical laminate theory with complex modulus approach. Then, an objective function was defined as a combination of an allowable bending deformation and external damping and a genetic algorithm was applied to search for an optimum set with respect to ply angles and stack sequences. Results show that an optimum laminate consists of two groups of layers: (i) one has ply angles well below 45$^{\circ}$ and the other far above 45$^{\circ}$ and (ii) the number of layers with low ply angles is much bigger than that with high ply angles. It is also found that a thick FMC shaft is desirable for both lateral flexibility and whirling stability. The genetic algorithm was effective in converging to several local optimums, whose laminates exhibit similar patterns as mentioned above.

• Physical Therapy Rehabilitation Science
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• v.2 no.2
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• pp.87-91
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• 2013

Objective: The present study was aimed at determining the effect of physical training on glutamate transporter activity in a middle cerebral artery occlusion (MCAO)-induced ischemia injury rat model. Design: Randomized controlled trial. Methods: In this study, we randomly divided them into three groups. Group I included non-occlusion sham controls (n=10), Group II included non-physical training after MCAO (n=10), and Group III included rats that were subjected to physical training after MCAO (n=10). Rats in the physical training group underwent treadmill training, which began at 24 h after MCAO and continued for 14 consecutive days. The training intensity was gradually increased from 5 m/min on the first day to 12 m/min on day 3, and it was maintained until day 14. Focal cerebral ischemia was examined in adult male Sprague-Dawley rats by using the MCAO model. We determined the functional outcomes for each rat on days 1, 7, and 14. Glutamate transporter-1 (GLT-1) activity in the cortex of rats from all three groups was examined at the end of the experiment. Results: Out result show that MCAO rats exhibited severe neurological deficits on the 1 day, and there was no statistically significant in each groups. We observed that the functional outcomes were improved at days 7 and 14 after middle cerebral artery occlusion, and GLT-1 activity was increased in the physical training group (p<0.05). Conclusions: These results indicated that physical training after focal cerebral ischemia exerts neuroprotective effects against ischemic brain injury by improving motor performance and increasing the levels of GLT-1 activity.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.131-136
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• 2013

The purpose of this study is to establish the flexural strengthening method of the concrete members. To accomplish this objective, a total of seven concrete beams were tested. From this study, it is found that the initial flexural stiffness and strength of the beams reinforced with NSM CFRP strips were significantly improved compared to the beam without CFRP strip. Failure of the beam reinforced with NSM strips is initiated by failure of NSM strips, eventually sudden explosive compressive failure in the loaded region. This strengthening method combined with NSM CFRP strips and high performance mortar for concrete cover recovery is evaluated by a good strengthening method for the strength, durability and good appearance of concrete structures.

• Computers and Concrete
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• v.26 no.4
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• pp.327-342
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• 2020

The objective of this study is to manufacture environmentally-friendly synthetic lightweight aggregates that may be used in the structural lightweight concrete production. The cold-bonding pelletization process has been used in the agglomeration of the pozzolanic materials to achieve these synthetic lightweight aggregates. In this context, it was aimed to recycle the waste fly ash by employing it in the manufacturing process as the major cementitious component. According to the well-known facts reported in the literature, it is stated that the main disadvantage of the synthetic lightweight aggregate produced by applying the cold-bonding pelletization technique to the pozzolanic materials is that it has a lower strength in comparison with the natural aggregate. Therefore, in this study, the metakaolin made of high purity kaolin and calcined kaolin obtained from impure kaolin have been employed at particular contents in the synthetic lightweight aggregate manufacturing as a cementitious material to enhance the particle crushing strength. Additionally, to propose a curing condition for practical attempts, different curing conditions were designated and their influences on the characteristics of the synthetic lightweight aggregates were investigated. Three substantial features of the aggregates, specific gravity, water absorption capacity, and particle crushing strength, were measured at the end of 28-day adopted curing conditions. Observed that the incorporation of thermally treated kaolin significantly influenced the crushing strength and water absorption of the aggregates. The statistical evaluation indicated that the investigated properties of the synthetic lightweight aggregate were affected by the thermally treated kaolin content more than the kaoline type and curing regime. Utilizing the thermally treated kaolin in the synthetic aggregate manufacturing lead to a more than 40% increase in the crushing strength of the pellets in all curing regimes. Moreover, two numerical formulations having high estimation capacity have been developed to predict the crushing strength of such types of aggregates by using soft-computing techniques: gene expression programming and artificial neural networks. The R-squared values, indicating the estimation performance of the models, of approximately 0.97 and 0.98 were achieved for the numerical formulations generated by using gene expression programming and artificial neural networks techniques, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.11
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• pp.1555-1559
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• 2003

The objective of the present study was to explore associations between five microsatellites linked to $Fec^B$ and $FecX^I$ genes and litter size in Small Tail Han sheep. The polymorphisms of five microsatellite loci, OarAE101, BM1329, BMS2508, TGLA54 and TGLA68 were detected in 244 ewes of Small Tail Han sheep. Analysis of association between three microsatellite loci (BMS2508, BM1329 and OarAE101) located in the 10 cM region covering the $Fec^B$ gene (Booroola gene) and litter size in Small Tail Han sheep indicated that BMS2508 had significant effect on litter size in the second parity (p<0.05), but no significant effect on litter size in the first parity (p>0.05), while the other two microsatellite loci had no significant effect on litter size in both the first and the second parity in Small Tail Han sheep (p>0.05). At microsatellite locus BMS2508, least squares means in the second parity of genotypes 101/111 and 99/109 were significantly higher than those of genotypes 99/99, 99/101, 99/111 and 99/115 (p<0.05); least squares mean in the second parity of genotype 101/111 was significantly higher than that of genotypes 109/111 and 111/111 (p<0.05). Results of this study also indicated that two microsatellite loci (TGLA54 and TGLA68) that confined the 28.7 cM region covering the $FecX^I$ gene (Inverdale gene) did not affect litter size in both the first and the second parity in Small Tail Han sheep significantly (p>0.05). The information found in the present study is very important for improving the reproductive performance in sheep breeds by marker assisted selection.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.6
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• pp.800-809
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• 2011

The objective of this study was to investigate the effects of different ratios of corn silage (CS): alfalfa hay (AH), and extruded soybeans (ESB) on milk yield, milk composition, blood metabolites, and fatty acids in milk fat and plasma. Ninety multiparous Holstein cows were arranged in a randomized block design experiment which lasted 14 weeks. Treatments were arranged as a $3{\times}3$ factorial with 0%, 5% or 10% ESB (dry matter basis) and three forage treatments: I) 30% CS, 10% AH and 10% Leymus chinense hay (LC); ii) 20% corn silage, 20% alfalfa hay and 10% LC; iii) 10% CS, 30% AH and 10% LC. Cows were allowed to consume a total mixed ration ad libitum. There was no change of dry matter intake when cows were fed the experimental diets. As more AH was added to the diets, milk yield, milk protein content and yield, and trans9, cis11-conjugated linoleic acids (CLA) concentrations in milk fat and plasma increased. When ESB were supplemented to the diets, milk yield, and trans9, cis11-CLA concentration in milk fat and plasma increased. When 10% ESB was added to the diet containing 30% AH the trans9, cis11-CLA content (1.46 g/100 g of total fatty acids) in milk was the highest among all treatments. These results suggests that AH could replace part of a CS diet and be a good forage source of diet for dairy cows to improve milk yield and milk composition. Meanwhile, ESB could be included in the diet with high AH to improve production performance of dairy cows.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1395-1403
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• 2012

The objective of the study was to quantify annual and seasonal differences in the chemical composition, in vitro gas production, in situ degradability and ruminal fermentation of grazing steers… diets. Diet samples were collected with four esophageal cannulated steers ($350{\pm}3$ kg BW); and four ruminally cannulated heifers ($342{\pm}1.5$ kg BW) were used to study the dry matter degradation and fermentation in rumen. Data were analyzed with repeated measurements split plot design. The crude protein, in vitro dry matter digestibility and metabolizable energy were higher during the first year of trial and in the summer (p<0.01). The values of calcium, phosphorus, magnesium, zinc and copper were higher in summer (p<0.05). The gas produced by the soluble and insoluble fractions, as well as the constant rate of gas production were greater in summer and fall (p<0.01). The ammonia nitrogen ($NH_3N$) and total volatile fatty acids concentrations in rumen, the soluble and degradable fractions, the constant rate of degradation and the effective degradability of DM and NDF were affected by year (p<0.05) and season (p<0.01). Our study provides new and useful knowledge for the formulation of protein, energetic and mineral supplements that grazing cattle need to improve their productive and reproductive performance.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.5
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• pp.609-615
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• 2014

Appetite-related neuropeptides proopiomelanocortin (POMC) and Neuropeptide Y (NPY) are essential for regulating feeding behavior and energy homeostasis. The objective of this study was to evaluate the effects of variants in POMC and NPY genes on growth, carcass and meat quality traits in rabbits. A total of six SNPs were identified for POMC (n = 2) and NPY (n = 4) genes by direct sequencing. Three SNPs were subsequently genotyped by using MassArray system (Sequenom iPLEXassay) in 235 individuals, which belong to three meat rabbit breeds, including 93 Ira rabbits; 81 Champagne rabbits and 61 Tianfu black rabbits. The SNP c.112-12G>T was in intron-exon boundaries (intron 1) of POMC gene, and the association analysis showed that individuals with TT genotype had a greater 84 d body weight (BW84), eviscerated weight and semi-eviscerated weight than those with GT genotype (p<0.05); the TT individuals were also higher than those GG in the ripe meat ratio (RMR) (p<0.05). The g.1778G>C SNP, which was in complete linkage with other three SNPs (g.1491G>A, g.1525G>T and g.1530C>T) in intron 1 of NPY gene, was significantly correlated with eviscerated slaughter percentage and semi-eviscerated slaughter percentage in rabbits, and the individuals with CC genotype had a better performance than CG genotype (p<0.05). These findings would provide primary clues for the biological roles of POMC and NPY underlying the rabbit growth-related traits.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.5
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• pp.628-635
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• 2018

Objective: To determine the effects of genomic breeding values (GBV) and single nucleotide polymorphisms (SNP) on the total number of piglets born (TNB) in 3 pig breeds (Berkshire, Landrace, and Yorkshire). Methods: After collecting genomic information (Porcine SNP BeadChip) and phenotypic TNB records for each breed, the effects of GBV and SNP were estimated by using single step best linear unbiased prediction (ssBLUP) method. Results: The heritability estimates for TNB in Berkshire, Landrace, and Yorkshire breeds were 0.078, 0.107, and 0.121, respectively. The breeding value estimates for TNB in Berkshire, Landrace, and Yorkshire breeds were in the range of -1.34 to 1.47 heads, -1.79 to 1.87 heads, and -2.60 to 2.94 heads, respectively. Of sows having records for TNB, the reliability of breeding value for individuals with SNP information was higher than that for individuals without SNP information. Distributions of the SNP effects on TNB did not follow gamma distribution. Most SNP effects were near zero. Only a few SNPs had large effects. The numbers of SNPs with absolute value of more than 4 standard deviations in Berkshire, Landrace, and Yorkshire breeds were 11, 8, and 19, respectively. There was no SNP with absolute value of more than 5 standard deviations in Berkshire or Landrace. However, in Yorkshire, four SNPs (ASGA 0089457, ASGA0103374, ALGA0111816, and ALGA0098882) had absolute values of more than 5 standard deviations. Conclusion: There was no common SNP with large effect among breeds. This might be due to the large genetic composition differences and the small size of reference population. For the precise evaluation of genetic performance of individuals using a genomic selection method, it may be necessary to establish the appropriate size of reference population.