• Structural Engineering and Mechanics
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• v.35 no.2
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• pp.127-140
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• 2010

This paper focuses on a number of criteria that enable controlling the influence of geometric simplification on the quality of finite element (FE) computations. To perform the mechanical simulation of a component, the corresponding geometric model typically needs to be simplified in accordance with hypotheses adopted regarding the component's mechanical behaviour. The method presented herein serves to compute an a posteriori indicator for the purpose of estimating the significance of each feature removal. This method can be used as part of an adaptive process of geometric simplification. If a shape detail removed during the shape simplification process proves to be influential on mechanical behaviour, the particular detail can then be reinserted into the simplified model, thus making it possible to readapt the initial simulation model. The fields of application for such a method are: static problems involving linear elastic behaviour, and linear thermal problems with stationary conduction.

• Wind and Structures
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• v.14 no.2
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• pp.133-151
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• 2011

For a detailed investigation of the dynamic behaviour of slender bridges under wind action especially the motion-induced fluid forces should be available not only for harmonic motions but also for more general ones. If linear transfer behaviour is assumed, the force-displacement relation for almost arbitrary motions can be handled in the frequency domain using aerodynamic transfer functions. In aerospace engineering as well as in bridge engineering, these functions are usually approximated by special kinds of complex-valued rational functions which depend on complex frequencies. The quality of this approximation is evaluated for several bridge cross sections in this article. It is shown that rational functions are for some sections scarcely suitable to realistically represent the transfer behaviour of motion-induced aerodynamic forces for arbitrarily complex frequencies.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.1
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• pp.28-38
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• 2012

The characteristics of vibration and noise of a compressor used for electric appliances have significant influence on the quality of the products. For improvement on the quality of electric appliances, investigations for understanding the dynamic behaviour of the compressor are essential. Since Virtual Lab for the dynamics model and MAXWELL for the electromagnetics model are separate software programs with no interface, the joint simulation of the models could not be performed. This study suggests a way to develop the compressor model capable of the joint simulation with MATLAB/SIMULINK linking a flexible multi-body dynamics model, a torque model, and an electricity control model. The compressor model is found to be able to perform I/O data transfer among the sub-models and joint simulation. The simulation results of the flexible body and rigid body dynamics models were compared to check availability of the joint simulation system. In addition, the simulated vibration and driving torque of the compressor mechanisms were compared with measurements. Through the simulations, the influence of springs and LDT on the dynamic behaviour of the compressor was examined. This study examines the influence of the dynamic behaviour of the compressor mechanisms through joint simulation of the flexible multi-body dynamics model and electromagnetic circuit allows analysis.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.4
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• pp.527-530
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• 1994

The effect of orally supplemented urea on eating and rumination behaviour of sheep fed a low-quality hay was investigated in this study. Daily time spent eating was not influenced by ruminal addition of urea, thus the eating rate (g DM/min) also did not change with urea supplementation. The rumination appearance (the lag time after eating) tended to be shorted with urea supplement than without supplement, but not significantly (p>0.05). Daily time spent ruminating was in the range of 600-630 min/d, and rumination index (ruminating time/100 g DM ingested) was 85 min. on the average for all the treatments, but there were no significant differences among the values in each treatment. Daily number of rumination periods tended to be smaller with urea supplement than with no urea, but not significantly (p>0.05), and cyclic rate was almost constant in all the treatments. From these results, it may be concluded that an administration of urea in sheep receiving hay diet could have little effect on eating and rumination behaviour, when it was given at two times a day.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.165-172
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• 2012

This study was designed to determine the effect of different floor space and type of finishing building on performance, behaviour and carcass quality of finishing pig. Three hundred and thirty six finishing pigs were alloted into two space allowance ($1.0m^2$and $2.5m^2$/pig) and two floor type (concrete slat and bedded with sawdust) of finishing building. There was no significant difference between the different space allowance in the body gain, feed intake and feed per gain. And also floor type of finishing building was not affected by the performance of finishing pig. Space allowance per pig affected the maintenance behaviour, but there was no significant difference between the floor type of finishing building in the spent time on lying, sitting and standing. Floor type was affected by the occurrence of standing behaviour, the finishing pigs in the bedded with sawdust showed less occurrence of standing. Carcass traits did not show any significant difference due to the difference of space allowance and floor type of finishing building. There was no significant difference in the chemical compositions of pork loin between the space allowance and floor type of finishing building.

• Steel and Composite Structures
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• v.29 no.1
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• pp.1-22
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• 2018

Multi-storey precast concrete skeletal structures are assembled from individual prefabricated components which are erected on-site using various types of connections. In the current design of these structures, beam-to-column connections are assumed to be pin jointed. Welded plate beam to-column connections have been used in the precast concrete industry for many years. They have many advantages over other jointing methods in component production, quality control, transportation and assembly. However, there is at present limited information concerning their detailed structural behaviour under bending and shear loadings. The experimental work has involved the determination of moment-rotation relationships for semi-rigid precast concrete connections in full scale connection tests. The study reported in this paper was undertaken to clarify the behaviour of such connections under symmetrical vertical loadings. A series of full-scale tests was performed on sample column for which the column geometry and weld arrangements conformed with successful commercial practice. Proprietary hollow core slabs were tied to the beams by tensile reinforcing bars, which also provide the in-plane continuity across the connections. The strength of the connections in the double sided tests was at least 0.84 times the predicted moment of resistance of the composite beam and slab. The secant stiffness of the connections ranged from 0.7 to 3.9 times the flexural stiffness of the attached beam. When the connections were tested without the floor slabs and tie steel, the reduced strength and stiffness were approximately a third and half respectively. This remarkable contribution of the floor strength and stiffness to the flexural capacity of the joint is currently neglected in the design process for precast concrete frames. In general, the double sided connections were found to be more suited to a semi-rigid design approach than the single sided ones. The behaviour of double sided welded plate connection test results are presented in this paper. The behaviour of single sided welded plate connection test results is the subject of another paper.

• Steel and Composite Structures
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• v.29 no.5
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• pp.603-622
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• 2018

Precast concrete structures are erected from individual prefabricated components, which are assembled on-site using different types of connections. In the present design of these structures, beam-to-column connections are assumed pin jointed. Bolted billet beam to-column connections have been used in the precast concrete industry for many years. They have many advantages over other jointing methods in component production, quality control, transportation and assembly. However, there is currently limited information concerning their detailed structural behaviour under vertical loadings. The experimental work has involved the determination of moment-relative rotation relationships for semi-rigid precast concrete connections in full-scale connection tests. The study reported in this paper was undertaken to clarify the behaviour of such connections under symmetrical vertical loadings. A series of full-scale tests was performed on sample column for which the column geometry and bolt arrangements conformed to successful commercial practice. Proprietary hollow core floor slabs were tied to the beams by 2T25 tensile reinforcing bars, which also provide the in-plane continuity across the connections. The contribution of the floor strength and stiffness to the flexural capacity of the joint is currently neglected in the design process for precast concrete frames. The flexural strength of the connections in the double-sided tests was at least 0.93 times the predicted moment of resistance of the composite beam and slab. The secant stiffness of the connections ranged from 0.94 to 1.94 times the flexural stiffness of the attached beam. In general, the double-sided connections were found to be more suited to a semi-rigid design approach than the single sided ones. The behaviour of double sided bolted billet connection test results are presented in this paper. The behaviour of single sided bolted billet connection test results is the subject of another paper.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1594-1599
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• 2005

The effects of long-term feeding of diets based on bermudagrass hay supplemented with lucerne hay cube (LH) or fermented bagasse feed (FBF) on the growth rate, feed efficiency, behaviour, gut development, carcass characteristics and meat quality of goats were investigated. Six spring-born 8-month-old male crossbred (Japanese Saanen${\times}$Tokara native goats) bucks weighing mean 21.6 kg were allotted to 2 treatment groups (3 animals each) and each animal had ad libitum access to feeds, i.e. bermudagrass hay (basal diet)+LH or FBF throughout the experiment. The FBF was produced by the solid-state fermentation of substrates containing dried sugarcane bagasse mixed with wheat bran in a ratio of 1:3 (w/w DM) with Aspergillus sojae. The live body weight, final weight and average daily gain were not different between treatments. Average basal diet intake of goats fed FBF diet was significantly higher than that fed LH diet (p<0.05), but average dry matter intake (DMI; g/day and g/$W^{0.75}$), feed conversion ratio, digestible crude protein (DCP) and total digestible nutrients (TDN) intake of experimental diets were not significantly different between treatments. Goats fed on LH and FBF diets had similar eating, rumination, resting and drinking behaviours, and blood constituents except for phosphorus content. Slaughter and carcass weights, net meat percentage [(total meat/carcass weight)${\times}$100], loin ratio [(loin/total meat)${\times}$100] and rib-eye area were not different between treatments. However, goats fed FBF diet had lower dressing percentage and higher bone/muscle ratio compared with goats fed LH diet (p<0.01). Empty gut and guts fill of goats fed FBF diet were significantly greater (p<0.05 and p<0.01, respectively) than those fed LH diet. The weights of rumen and abomasum were also significantly heavier in goats fed FBF diet (p<0.05), but the length and density of papillae of rumen in goats were not different between treatments. Although meat composition of loin was not different in both groups, the meat of goats fed FBF diet was superior to that of LH diet in flavor, aroma and overall quality of loin (p<0.01). In conclusion, the nature of the diet consumed voluntarily did not affect subsequent growth, nutrient intake and behaviour of goats but had an influence on carcass traits and sensory evaluation of meat partly, when either of LH or FBF was fed with bermudagrass hay.

• Tunnel and Underground Space
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• v.14 no.3
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• pp.215-228
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• 2004

Rock mass contains discontinuities such as faults and joints, and their mechanical properties and spatial distribution dominate the stability of rock mass. Because the deformation of rock mass occurs discontinuities in many cases. However in the case of poor quality rock mass under high stresses, the deformation along intact rock can also influence the structure's stability. In this study, two dimensional finite element program was developed with a rheological model to analyze the stability of the structure excavated in jointed rock mass. The “equivalent material” approach was used assuming intact rock, joints and rock bolts as visco-plastic materials. The program was verified by analysing an intact rock model, a jointed rock mass model and a reinforced jointed rock mass model. The displacement was examined in each model with changing the intact rock behaviour as elastic and visco-plastic. In the case of poor quality rock mass under high stresses, e assumption of visco-plastic behaviour of intact rock resulted in larger displacement than when assuming elastic behaviour for intact rock. Therefore it is recommended to add intact rock's visco-plastic behaviour to the existing model, which only assumes visco-plastic behaviour of joints and rock bolts.

• International Journal of Quality Innovation
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• v.6 no.2
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• pp.46-58
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• 2005

The internet is enabling a new economy based on the networking of human knowledge. While the benefits of connecting people to people, people to information and people to data within an organization are becoming more recognized and appreciated, much less is known about managing knowledge creation and dissemination across corporate boundaries. This paper addresses the challenges associated with selecting the best collaborative strategy and managing relationships which span organizational cultures and boundaries.