In this study, four 1/5 scaled shaking table tests were conducted to investigate the seismic performance of recycled concrete frame-shear wall structures with different recycled aggregates replacement rates and concea...In this study, four 1/5 scaled shaking table tests were conducted to investigate the seismic performance of recycled concrete frame-shear wall structures with different recycled aggregates replacement rates and concealed bracing detail. The four tested structures included one normal concrete model, one recycled coarse aggregate concrete model, and two recycled coarse and fi ne aggregate concrete models with or without concealed bracings inside the shear walls. The dynamic characteristics, dynamic response and failure mode of each model were compared and analyzed. Finite element models were also developed and nonlinear time-history response analysis was conducted. The test and analysis results show that the seismic performance of the recycled coarse aggregate concrete frame-shear wall structure is slightly worse than the normal concrete structure. The seismic resistance capacity of the recycled concrete frame-shear wall structure can be greatly improved by setting up concealed bracings inside the walls. With appropriate design, the recycled coarse aggregate concrete frame-shear wall structure and recycled concrete structure with concealed bracings inside the walls can be applied in buildings.展开更多
With sales at a quarter of a trillion and over 1.3 million employees,Wal-Mart has been the biggest retailing success ever before.A lot of Wal-Mart’s success was attributed to the strong and pervasive culture at the c...With sales at a quarter of a trillion and over 1.3 million employees,Wal-Mart has been the biggest retailing success ever before.A lot of Wal-Mart’s success was attributed to the strong and pervasive culture at the company.China’s retailing industry should really learn something about corporate culture-building from this excellent enterprise,so that one day it would become a strong competitor both home and abroad in retailing industry.展开更多
Short-leg walking boots are a common intervention for acute and chronic lower extremity injury.Few studies have examined the neuromuscular adaptations associated with short-leg walking boots and no previous study has ...Short-leg walking boots are a common intervention for acute and chronic lower extremity injury.Few studies have examined the neuromuscular adaptations associated with short-leg walking boots and no previous study has investigated timing characteristics of muscle activation during gait.The purpose of the current study was to examine the timing and amplitudes of muscle activation of the extrinsic ankle musculature during walking in two types of short-leg walking boots.Methods:Eleven healthy young adults performed five level walking trials at a self-selected pace in each of three conditions:normal walking,Gait Walker and Equalizer short-leg walking boots.Ground reaction forces were collected from a force platform while surface electromyography (EMG)was collected from the tibialis anterior,peroneus longus and medial gastrocnemius.EMG signals were rectified and smoothed using the root mean squared with a 20-ms smoothing window and were normalized to the largest mean of the normal walking trials.A repeated measures analysis of variance was used to assess the effect of short-leg walking boots on the onset,duration and amplitude of muscle activation.Results:Short-leg walking boots were generally associated with earlier onsets of muscle activation and longer durations of muscle activation.However,there was no reduction in EMG amplitude.Conclusion:The findings of this study show that the induced alterations in muscle activation patterns may limit the short-leg walking boots.Copyright(C)2012,Shanghai University of Sport.Production and hosting by Elsevier B.V.All rights reserved.展开更多
The development of the construction sector is rapidly growing,which induce competition at global level.In order to achieve the current economic development,more high-rise buildings construction projects were commenced...The development of the construction sector is rapidly growing,which induce competition at global level.In order to achieve the current economic development,more high-rise buildings construction projects were commenced without considering importance of the land to human and other living organism.On the other hand,the quality and safety aspect of the engineering technology used must be analyzed carefully and to be the primary aim for engineers to reduce any risk of harm in future.Many of the high-rise buildings in China consist of a frame or skeleton of reinforced concrete wall which need to be strengthened with shear walls to improve the stability and safety of the structures.According to practical work experience and relevant theoretical knowledge,the researcher introduced the reinforcement construction technology of frame-shear wall for high-rise buildings in depth from aspects like the arrangement of steel bar,construction preparation,steel bar anchorage,precautions to follow for the related work in future.展开更多
Wal-Mart, the world famous retailing giant, set its foot on the land of China 17 years ago. Now despite of its success elsewhere as well as its confidence and ambition to"conquer"the vast market China which ...Wal-Mart, the world famous retailing giant, set its foot on the land of China 17 years ago. Now despite of its success elsewhere as well as its confidence and ambition to"conquer"the vast market China which shows great potential, Wal-Mart fails to reach its goal anyway. To be more exact, it is far from the goal. Considering its unexpected failure, this article mainly discusses why Wal-Mart has experienced such a hard time in China. The issue is analyzed from the following aspects, namely cultural dif ference, distribution, management and public relationship.展开更多
基金National Science and Technology Support Program of China under Grant No.2011BAJ08B02Natural Science Foundation of Beijing under Grant No.8132016Beijing City University Youth Backbone Talent Training Project under Grant No.PHR201108009
文摘In this study, four 1/5 scaled shaking table tests were conducted to investigate the seismic performance of recycled concrete frame-shear wall structures with different recycled aggregates replacement rates and concealed bracing detail. The four tested structures included one normal concrete model, one recycled coarse aggregate concrete model, and two recycled coarse and fi ne aggregate concrete models with or without concealed bracings inside the shear walls. The dynamic characteristics, dynamic response and failure mode of each model were compared and analyzed. Finite element models were also developed and nonlinear time-history response analysis was conducted. The test and analysis results show that the seismic performance of the recycled coarse aggregate concrete frame-shear wall structure is slightly worse than the normal concrete structure. The seismic resistance capacity of the recycled concrete frame-shear wall structure can be greatly improved by setting up concealed bracings inside the walls. With appropriate design, the recycled coarse aggregate concrete frame-shear wall structure and recycled concrete structure with concealed bracings inside the walls can be applied in buildings.
文摘With sales at a quarter of a trillion and over 1.3 million employees,Wal-Mart has been the biggest retailing success ever before.A lot of Wal-Mart’s success was attributed to the strong and pervasive culture at the company.China’s retailing industry should really learn something about corporate culture-building from this excellent enterprise,so that one day it would become a strong competitor both home and abroad in retailing industry.
基金funded in part by a grant from DeRoyal Industries,Inc.,Powell,TN,USA
文摘Short-leg walking boots are a common intervention for acute and chronic lower extremity injury.Few studies have examined the neuromuscular adaptations associated with short-leg walking boots and no previous study has investigated timing characteristics of muscle activation during gait.The purpose of the current study was to examine the timing and amplitudes of muscle activation of the extrinsic ankle musculature during walking in two types of short-leg walking boots.Methods:Eleven healthy young adults performed five level walking trials at a self-selected pace in each of three conditions:normal walking,Gait Walker and Equalizer short-leg walking boots.Ground reaction forces were collected from a force platform while surface electromyography (EMG)was collected from the tibialis anterior,peroneus longus and medial gastrocnemius.EMG signals were rectified and smoothed using the root mean squared with a 20-ms smoothing window and were normalized to the largest mean of the normal walking trials.A repeated measures analysis of variance was used to assess the effect of short-leg walking boots on the onset,duration and amplitude of muscle activation.Results:Short-leg walking boots were generally associated with earlier onsets of muscle activation and longer durations of muscle activation.However,there was no reduction in EMG amplitude.Conclusion:The findings of this study show that the induced alterations in muscle activation patterns may limit the short-leg walking boots.Copyright(C)2012,Shanghai University of Sport.Production and hosting by Elsevier B.V.All rights reserved.
文摘The development of the construction sector is rapidly growing,which induce competition at global level.In order to achieve the current economic development,more high-rise buildings construction projects were commenced without considering importance of the land to human and other living organism.On the other hand,the quality and safety aspect of the engineering technology used must be analyzed carefully and to be the primary aim for engineers to reduce any risk of harm in future.Many of the high-rise buildings in China consist of a frame or skeleton of reinforced concrete wall which need to be strengthened with shear walls to improve the stability and safety of the structures.According to practical work experience and relevant theoretical knowledge,the researcher introduced the reinforcement construction technology of frame-shear wall for high-rise buildings in depth from aspects like the arrangement of steel bar,construction preparation,steel bar anchorage,precautions to follow for the related work in future.
文摘Wal-Mart, the world famous retailing giant, set its foot on the land of China 17 years ago. Now despite of its success elsewhere as well as its confidence and ambition to"conquer"the vast market China which shows great potential, Wal-Mart fails to reach its goal anyway. To be more exact, it is far from the goal. Considering its unexpected failure, this article mainly discusses why Wal-Mart has experienced such a hard time in China. The issue is analyzed from the following aspects, namely cultural dif ference, distribution, management and public relationship.
