The recent slowdown in the residential and commercial building sectors has resulted in significant unemployment. Given the experience of these construction workers, it may be appropriate for transportation and public ...The recent slowdown in the residential and commercial building sectors has resulted in significant unemployment. Given the experience of these construction workers, it may be appropriate for transportation and public works agencies to assess the potential to retrain these workers for the transportation sector. This widens the pool of available workers, and brings workers with compatible skill sets to the transportation industry. This paper examines the pool of eligible workers, discusses the potential benefits and challenges of bringing these workers into the transportation sector, and identifies programs that have been undertaken to re-train workers for the transportation sector. A program to re-train construction workers from the residential and commercial sector for the transportation sector is presented, including specific training issues to facilitate the successful transition from residential and commercial construction to transportation construction.展开更多
This study gives a comparison between what occurs when braking on a MOT （Ministry of Transport） brake tester. The results from this research and the exhaustive comparative study carried out by the mechanical enginee...This study gives a comparison between what occurs when braking on a MOT （Ministry of Transport） brake tester. The results from this research and the exhaustive comparative study carried out by the mechanical engineering staffs at the mechanical laboratory at MOT stations in cities such as： Elche, Pilar de la Horadada and Orihuela from Alicante region [2] have led to the following main conclusions： this paper demonstrates that MOT brake testing results can vary depending on parameters variation such as： distance between rollers, roller diameter, roughness of rollers and velocity of the brake test.展开更多
In a flank array on an unmanned underwater vehicle （UUV）, self-generated noise which has broadband and colored spectrum property in frequency and spatial domain is the main factor affecting the performance of weak s...In a flank array on an unmanned underwater vehicle （UUV）, self-generated noise which has broadband and colored spectrum property in frequency and spatial domain is the main factor affecting the performance of weak signal detection, so the technique of adaptive noise cancellation （ANC） as well as physical denoising and active noise cancellation are often used in practice. Because ANC is based on correlations, improvements in performance come from better correlation between reference signals and primary signals. Taking full advantage of the characteristics of flank arrays and the characteristics of information obtained from hydrophones, a new method for reference signal acquisition for adaptive noise cancellation is proposed, in which the multi-channel reference signals are obtained by accurate delaying for a given direction of arrival （DOA） and differencing between adjacent outputs of array elements. The validity of the proposed method was verified through system modeling simulations and lake experiments which showed good performance with little additional computational burden.展开更多
The traffic bottleneck plays a key role in most of the natural and artificial network. Here we present a simply model for bottleneck dynamical characteristics consideration the reliability on the complex network by ta...The traffic bottleneck plays a key role in most of the natural and artificial network. Here we present a simply model for bottleneck dynamical characteristics consideration the reliability on the complex network by taking into account the network topology characteristics and system size. We find that there is a critical rate of flow generation below which the network traffic is free but above which traffic congestion occurs. Also, it is found that random networks have larger critical flow generating rate than scale free ones. Analytical results may be practically useful for designing networks, especially for the urban traffic network.展开更多
基金supported by a Key SciTech Project of Shandong Province(2004GG1104001),a Key Project of the National Natural Science Foundation of China(60334020) ,an Open Project Research of the Key Laboratory of Complex System &Intelligence Science of Chinese Academy of Sciences(20050101) ,aProject of the National Natural Science Foundation of China (60504025) ,a Doctoral Fund Project of Shandong Academy of Sciences (2005006) ,a KeyProject of Shandong Academy of Sciences (2005029)
文摘The recent slowdown in the residential and commercial building sectors has resulted in significant unemployment. Given the experience of these construction workers, it may be appropriate for transportation and public works agencies to assess the potential to retrain these workers for the transportation sector. This widens the pool of available workers, and brings workers with compatible skill sets to the transportation industry. This paper examines the pool of eligible workers, discusses the potential benefits and challenges of bringing these workers into the transportation sector, and identifies programs that have been undertaken to re-train workers for the transportation sector. A program to re-train construction workers from the residential and commercial sector for the transportation sector is presented, including specific training issues to facilitate the successful transition from residential and commercial construction to transportation construction.
文摘This study gives a comparison between what occurs when braking on a MOT （Ministry of Transport） brake tester. The results from this research and the exhaustive comparative study carried out by the mechanical engineering staffs at the mechanical laboratory at MOT stations in cities such as： Elche, Pilar de la Horadada and Orihuela from Alicante region [2] have led to the following main conclusions： this paper demonstrates that MOT brake testing results can vary depending on parameters variation such as： distance between rollers, roller diameter, roughness of rollers and velocity of the brake test.
基金the National Natural Science Foundation of China under Grant No.60572098
文摘In a flank array on an unmanned underwater vehicle （UUV）, self-generated noise which has broadband and colored spectrum property in frequency and spatial domain is the main factor affecting the performance of weak signal detection, so the technique of adaptive noise cancellation （ANC） as well as physical denoising and active noise cancellation are often used in practice. Because ANC is based on correlations, improvements in performance come from better correlation between reference signals and primary signals. Taking full advantage of the characteristics of flank arrays and the characteristics of information obtained from hydrophones, a new method for reference signal acquisition for adaptive noise cancellation is proposed, in which the multi-channel reference signals are obtained by accurate delaying for a given direction of arrival （DOA） and differencing between adjacent outputs of array elements. The validity of the proposed method was verified through system modeling simulations and lake experiments which showed good performance with little additional computational burden.
基金Supported by National Natural Science Foundation of China under Grant Nos.70871009 and 70801005Beijing Natural Science Foundation under Grant No 8102029+1 种基金Program for New Century Excellent Talents in University under Grart No.NCET-09-0208the Foundation of State Key Laboratory of Rail Traffie Control,and Safety under Grant No.RCS2010ZT001
文摘The traffic bottleneck plays a key role in most of the natural and artificial network. Here we present a simply model for bottleneck dynamical characteristics consideration the reliability on the complex network by taking into account the network topology characteristics and system size. We find that there is a critical rate of flow generation below which the network traffic is free but above which traffic congestion occurs. Also, it is found that random networks have larger critical flow generating rate than scale free ones. Analytical results may be practically useful for designing networks, especially for the urban traffic network.
