• International Journal of Concrete Structures and Materials
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• v.6 no.2
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• pp.79-85
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• 2012

This paper presents the differences in growth of time-dependent strain values in reinforced cement concrete (RCC) and pre-stressed concrete (PSC) flexural members through experiment. It was observed that at any particular age, the time-dependent strain values were less in RCC beams than in PSC beams of identical size and grade of concrete. Variables considered in the study were percentage area of reinforcement, span of members for RCC beams and eccentricity of applied pre-stress force for PSC beams. In RCC beams the time-dependent strain values increases with reduction in percentage area of reinforcement and in PSC beams eccentricity directly influences the growth of time-dependent strain. With increase in age, a non-uniform strain develops across the depth of beams which influence the growth of concave curvature in RCC beams and convex curvature in PSC beams. The experimentally obtained strain values were compared with predicted strain values of similar size and grade of plane concrete (PC) beam using ACI 318 Model Code and found more than RCC beams but less than PSC beams.

• Journal of the Ergonomics Society of Korea
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• v.27 no.3
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• pp.1-6
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• 2008

Individual finger/total grip forces, and subjective preferences for various individual finger grip spans (i.e., four fingers had identical grip spans or different grip spans) were evaluated by using an "Adjustable Multi-Finger Force Measurement (MFFM) System". In this study, three grip spans were defined as follows: a 'favorite grip span' which is the span with the highest subjective preference; a 'maximum grip span' which is the span with the highest total grip force; a 'maximum finger grip span' which is a set of four grip spans that had maximum finger grip forces associated with the index, middle, ring, and little fingers, respectively. Ten males were recruited from university population for this study. In experiment I, each participant tested the maximum grip force with five grip spans (45 to 65mm) to investigate grip forces and subjective preferences for three types of grip spans. Results showed that subjective preferences for grip spans were not coincidence with the performance of total grip forces. It was noted that the 'favorite grip span' represented the lowest total grip force, whereas the 'maximum finger grip span' showed the lowest subjective preferences. The individual finger forces and the average percentage contribution to the total finger force were also investigated in this study. The findings of this study might be valuable information for designing ergonomics hand-tools to reduce finger/hand stress as well as to improve tool users' preferences and performance.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.8
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• pp.1195-1201
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• 2009

An experiment was conducted to evaluate the effects of dietary alpha-lipoic acid (LA) on growth performance, carcass characteristics and meat quality in Arbor Acres broilers. A total of 240 1-d-old male Arbor Acres broilers were randomly allocated to 4 dietary treatments (0, 300 ppm, 600 ppm, and 900 ppm dietary LA supplementation, respectively). Birds were slaughtered at 42 days old. Live body weight (BW), average daily gain (ADG), average feed intake (AFI), feed conversion ratio (FCR), dressing percentage, breast muscle percentage, thigh muscle percentage, abdominal fat percentage, muscle color (L*, a*, b*), pH values at 24 h postmortem, meat shear force value (SFV) and anti-oxidative ability were measured. Results showed that addition of 600 ppm or 900 ppm LA decreased BW (p<0.01), ADG (p<0.01) and AFI (p<0.05) compared with other diets. FCR was not affected by dietary LA content. LA had no marked effect on dressing percentage, breast muscle percentage or thigh muscle percentage. Abdominal fat percentage was lower (p<0.05) in the 900 ppm LA supplementation group than the control group. Dietary 900 ppm LA increased (p<0.05) breast and thigh muscle pH value at 24 h postmortem compared with the control treatment. Dietary LA increased thigh muscle a* value, though no significant difference was found in thigh muscle a* value among the treatments. Dietary LA significantly decreased breast muscle L* value (p<0.05), breast muscle b* value (p<0.01) and thigh muscle b* value (p<0.05). Broilers fed LA had higher breast muscle a* value (p<0.05) and thigh muscle L* value (p<0.05). All test groups had lower (p<0.05) breast muscle SFV than the control group. Dietary 600 ppm or 900 ppm LA both decreased (p<0.01) thigh muscle SFV compared with the control treatment. Dietary 900 ppm LA significantly increased (p<0.05) TAOC, SOD and GSHPx compared with no LA treatment. Broilers fed LA had lower (p<0.01) MDA compared with the control treatment. These results suggested that dietary LA enhanced the anti-oxidative ability and oxidative stability, and contributed to the improvement of meat quality in broilers.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.1B
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• pp.57-62
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• 2011

The river disaster caused by installation of hydraulic structures on the river gives varieties to flowing water stream, tractive force and so on. In this study, the changes of tractive force and energy from the side weir installation for the purpose of flood control was analyzed through laboratory experiment. The experiments of the pre and after-installation have been performed under conditions that waterway is trapezoidal shape, waterway slope ranges are from 0.1 to 1.0 percentage, and flow rates are 25 l/sec. As results, the specific energy ratio increases in the higher slope and at a certain point, larger specific energy ratio showed than 1 in the 1.0% slope. The tractive force ratio decreases in higher slope and the sections that tractive force ratio appeared higher than 1 are more widespread in the direction of downstream. And calculated tractive force is about 1.3.

• YAKHAK HOEJI
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• v.26 no.4
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• pp.239-251
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• 1982

The rate of deterioration of contractile force of isolated hearts from control and panax ginseng treated rats was determined and response of contractile force of the hearts from ginseng treated rats to several autonomic and other drugs was investigated. Rats weighing 150-250g were administrered orally with ginseng ethanol extract (100mg/kg) and total ginseng saponin (50mg/kg/day) for a week. Ginsenoside Rb$_{1}$ (5mg/kg/day) and ginsenoside Re (5mg/kg/day) were administered respectively for a week. The isolated hearts from rats were perfused with Krebs-Henseleit solution by using Langendorff perfusion apparatus. The control group was only able to maintain approximately 75.5% of their initial strength after 60 min of perfusion, whereas ginseng ethanol extract, total ginseng saponin treated hearts were able to sustain nearly their initial strength even after 60 min. Ginsenoside Rol treated hearts also sustained 93% of their initial strength, but there was no significant difference in the deterioration percentage of the contractile force of ginsenoside Re treated hearts. Experiments were conducted to study the response to perfusion of ginseng treated animal heart with epinephrine, isoproterenol, propranolol, and phenobarbital. The isolated hearts were perfused with Krebs-Henseleit solution containing epinephrine (10$^{-6}$ M), isoproterenol ($10^{-7}$M), propranolol ($10^{-6}$M) and phenobarbital (7{\times}10^{-3}M$) respectively. The maximum inotropic effect of epinephrine and isoproterenol was observed after 2~3 minutes of drug perfusion. Effect of epinephrine on ginseng ethanol extract and total ginseng saponin treated hearts was reduced compared with control. On the other hand, this phenomenon was not observed in ginsenoside Re treated rats but on ginsenoside $Rb_{1}$ treated rats. The positive inotropic effect of isoproterenol was reduced in the hearts from ginseng treated rats compared with control heart, Propranolol or phenobaribital decreased the contractile force in the control rats. The depressant effect of propranolol and phenobarbitat on ginseng treated rat hearts was less than those of control rat hearts. The result suggest that ginseng ethanol extract , ind total ginseng saponin and ginsenoside $Rb_{1}$ may protect the deterioration of contractile force of the heart and may attenuate the response to several drugs on hearts.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.1321-1327
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• 2006

This paper presents the calculation of unbalanced magnetic pull (UMP) that causes rotor misalignment in induction motor. The excessive noise and vibration will be occurred by means of rotor misalignment. Angular misalignment of rotor will produce air-gap permeance wave which is function of axial and circumferential coordinate. In this paper, the UMP is calculated using permeance and magneto motive force (MMF) in the case of static and dynamic misalignment. Based on the percentage of misalignment, the result shows that the UMP and magnetic pressure are increased according to the increasing of misalignment. The UMP is occurred not only in It frequency component but also the others.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.12
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• pp.1639-1644
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• 2010

An experiment was conducted to evaluate the effects of dietary acetyl-L-carnitine (ALC) on growth performance, carcass characteristics, meat quality and lipid metabolism in broilers. A total of 240 one-day-old male Arbor Acres broilers were randomly allocated to 4 dietary treatments (0, 300, 600, and 900 mg/kg dietary ALC supplementation, respectively). Compared with the control treatment, addition of ALC resulted in lower (linear effect, p<0.05) ADG and AFI. Abdominal fat percentage decreased (linear effect, p<0.05) as dietary ALC was increased, but there was no effect on dressing percentage, breast muscle percentage or thigh muscle percentage. Breast muscle pH value 24 h post-mortem increased (linear effect, p<0.05), but there were no significant differences among treatments. However, thigh muscle pH value increased (linear effect, p<0.05) as dietary ALC was increased. Breast and thigh muscle $a^*$ values increased (linear effect, p<0.05), and breast and thigh muscle $b^*$ values decreased (linear effect, p<0.05) with increased ALC in the diet. In addition, breast and thigh muscle shear force value decreased (linear effect, p<0.05) as dietary ALC was increased. Total cholesterol, triglyceride, low-density lipoprotein cholesterol and lipoprotein lipase decreased (linear effect, p<0.05) and free fatty acid and lipase in serum increased (linear effect, p<0.05) with increased ALC in diets.

• Advances in Computational Design
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• v.2 no.1
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• pp.15-28
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• 2017

One of the major developments in seismic design over the past few decades is the increased emphasis for limit states design now generally termed as Performance Based Engineering. Performance Based Seismic Design (PBSD) uses Displacement Based Design (DBD) methodology wherein structures are designed for a target level of displacement rather than Force Based Design (FBD) methodology where force or strength aspect is being used. Indian codes still follow FBD methodology compared to other modern codes like CalTrans, which follow DBD methodology. Hence in the present study, a detailed review of the two most common design methodologies i.e., FBD and DBD is presented. A critical evaluation of both these methodologies by comparing the seismic performance of bridge models designed using them highlight the importance of adopting DBD techniques in Indian Standards also. The inherent discrepancy associated with FBD in achieving 'seismic regularity' is highlighted by assessing the seismic performance of bridges with varied relative height ratios. The study also encompasses a brief comparison of the seismic design and detailing provisions of IRC 112 (2011), IRC 21 (2000), AASHTO LRFD (2012) and CalTrans (2013) to evaluate the discrepancies on the same in the Indian Standards. Based on the seismic performance evaluation and literature review a need for increasing the minimum longitudinal reinforcement percentage stipulated by IRC 112 (2011) for bridge columns is found necessary.

• Korean Journal of Applied Biomechanics
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• v.28 no.1
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• pp.29-35
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• 2018

Objective: The purpose of this study was to determine the asymmetry of vertical ground reaction force (GRF) components between dominant and non-dominant legs in rested and fatigued states in prolonged running. Method: Twenty healthy men, heel strikers, were included (age: $24.00{\pm}5.0years$; height: $176.1{\pm}6.0cm$; body mass: $69.0{\pm}6.0kg$) in this study. Subjects ran on an instrumented treadmill for 130 minutes. During treadmill running, GRF data (1,000 Hz) were collected for 20 strides at five minutes (rested) and 125 minutes (fatigued) running while they were unaware of collecting data. Asymmetry indexes (ASI) were calculated to quantify the asymmetry magnitude in rested and fatigued states. Paired t-test was used to verify the differences between dominant and non-dominant legs in rested and fatigued states. In addition, one-way repeated measure analysis of variance was applied for comparison of ASI of both states. The level of significance was set at p < .05. Results: Passive force peak magnitude, loading rate, and impulse affecting the development of running injury were found significantly greater in dominant leg than in non-dominant leg at rested state (p < .05). However, passive force peak time and active force peak magnitude were found significantly different between legs in fatigued state (p < .05). To determine changes in percentage of asymmetry between legs in both states, ASI was used. ASI for all variables increased in fatigued state; however, no significant differences were found between both states. Conclusion: This study found that fatigue did not affect differences in vertical GRF between dominant and non-dominant legs and asymmetry changes.

• The Journal of Engineering Geology
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• v.17 no.4
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• pp.525-534
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• 2007

The peculiarity of end-expanded soil nailing method(EESNM) is in fixing the wedge-type steel body spreaded by collars and grouting its surroundings by cement milk within soils, after extending hole bottom over drilling hole diameter with top drill bit. The present study was done to establish the effect of this method. Laboratory model test were carried out to investigate the behavior characteristics with the performance of the pull-out test and failure experiment, after preparing soil test box having 1,300mm length, width 1,000mm, and height 1,100mm, and the same experimental condition was set up to compare with the general soil nailing method(GSNM). The pull-out force of about 23 percentage was increased, and the horizontal displacements 1.2 from 9.1 percentage in soil-nailed wall decreased in EESNM compare with GSNM. The axial force acting on nail increased considerably at load level over 7 ton in EESNM and 5 ton in GSNM. The predicted failure line from the maxima analyzed by axial tensile strain located at long distance from soil-nailed wall in EESNM. The EESNM demonstrated the superiority of reinforcement effect in comparison with GSNM from the results above mentioned.