New Scale Technologies推出一款新型OEM电机控制器,用于其获得专利的压电式SQUIGGLE电机。该新型MC-1000驱动器将该公司的SQ-2000电源/电机控制器整合为一个单一的卡,可以方便地集成到OEM仪器中。MC-1000控制器产生驱动微型SQL系列...New Scale Technologies推出一款新型OEM电机控制器,用于其获得专利的压电式SQUIGGLE电机。该新型MC-1000驱动器将该公司的SQ-2000电源/电机控制器整合为一个单一的卡,可以方便地集成到OEM仪器中。MC-1000控制器产生驱动微型SQL系列或SQ-100系列线性SQUIGGLE电机所需的两相超声波型。展开更多
We use the latest data to investigate observational constraints on the new generalized Chaplygin gas (NGCG) model. Using the Markov Chain Monte Carlo method, we constrain the NGCG model with type Ia supernovae from ...We use the latest data to investigate observational constraints on the new generalized Chaplygin gas (NGCG) model. Using the Markov Chain Monte Carlo method, we constrain the NGCG model with type Ia supernovae from the Union2 set (557 data), the usual baryonic acoustic oscillation (BAO) observation from the spectroscopic Sloan Digital Sky Survey data release 7 galaxy sample, the cosmic mi- crowave background observation from the 7-year Wilkinson Microwave Anisotropy Probe results, newly revised data on H(z), as well as a value of θBAO (Z = 0.55) = (3.90° ±0.38°) for the angular BAO scale. The constraint results for the NGCG model are ωX=-1.0510+0.1563-0.1685(1σ)+0.2226-0.2398(2σ),η=1.0117+0.0469-0.0502(1σ)+0.0693-0.0716(2σ)and ΩX=0.7297+0.0229-0.0276(1σ)+0.0329-0.0402(2σ), which give a rather stringent constraint. From the results, we can see that a phantom model is slightly favored and the proba- bility that energy transfers from dark matter to dark energy is a little larger than the inverse.展开更多
Expansive soil is sensitive to dry and wet environment change. And the volume deformation and inflation pressure of expansive soil may induce to cause the deformation failure of roadbed or many other adverse effects. ...Expansive soil is sensitive to dry and wet environment change. And the volume deformation and inflation pressure of expansive soil may induce to cause the deformation failure of roadbed or many other adverse effects. Aimed at a high-speed railway engineering practice in the newly built Yun-Gui high-speed railway expansive soil section in China, indoor vibration test on a full-scaled new cutting subgrade model is carried out. Based on the established track-subgrade-foundation of expansive soil system dynamic model test platform, dynamic behavior of new cutting subgrade structure under train loads coupling with extreme service environment(dry, raining, and groundwater level rising) is analyzed comparatively. The results show that the subgrade dynamic response is significantly influenced by service conditions and the dynamic response of subgrade gradually becomes stable with the increasing vibration times under various service environment conditions. The vertical dynamic soil stress is related with the depth in an approximate exponential function, and the curves of vertical dynamic soil stress present a "Z" shape distribution along transverse distance. The peak value of dynamic soil stress appears below the rail, and it increases more obviously near the roadbed surface. However, the peak value of dynamic soil stress is little affected outside 5.0 m of center line. The vibration velocity and acceleration are in a quadratic curve with an increase in depth, and the raining and groundwater level rising increase both the vibration velocity and the acceleration. The vertical deformations at different depths are differently affected by service environment in roadbed. The deformation of roadbed increases sharply when the water gets in the foundation of expansive soil, and more than 60% of the total deformation of roadbed occurs in expansive soil foundation. The laid waterproofing and drainage structure layer, which weakens the dynamic stress and improves the track regularity, presents a positive effect on the control deformation of roadbed surface. An improved empirical formula is then proposed to predict the dynamic stress of ballasted tracks subgrade of expansive soil.展开更多
According to the basic features of socio economic development in China, the paper retrospects the developmental process of Chinese cities in the 20th century. Based on lots of data and related research achievements, f...According to the basic features of socio economic development in China, the paper retrospects the developmental process of Chinese cities in the 20th century. Based on lots of data and related research achievements, five new patterns of Chinese urban development are pointed out, that is 1) regional disparity of urban development in China is still obvious and large; 2) cities in developed region develop in the form of agglomeration and coordination; 3) spatial layout shape of Chinese cities appears relatively tight, and there exists great outside expansion inclination; 4) the construction of exploitation zone becomes the new important factor of urban development in the 1990s; 5) number increase of cities at county level become the main tide of urban development, but cause the discrete understanding for the concept of urban substantial region, which construct a challenge to urban management. In the end the article puts forward a series thoughts on the future trends and countermeasures of urban development in China.展开更多
Ever since involvement of the Binhai New Area into the national development strategy, carrying out highly effective financing promptly will play the pivotal role to implement its economic development strategy smoothly...Ever since involvement of the Binhai New Area into the national development strategy, carrying out highly effective financing promptly will play the pivotal role to implement its economic development strategy smoothly. In this paper, based on nature of regional financing, the descriptive analysis for the financing condition of the Binhai New Area is carried on. And also based on financing restraint theory and the neoclassic investment model, a real diagnosis analysis for the financing constraint condition of the Binhai New Area is studied. Finally, the existed questions in it are pointed out, and propose the correlative improvement countermeasure is put forward.展开更多
基金supported by the National Natural Science Foundation of China under the Distinguished Young Scholar program(Grant No. 10825313)the National Basic Research Program of China (973 program,Grant No. 2012CB821804)the Fundamental Research Funds for the Central Universities and Scientific Research Foundation of Beijing Normal University
文摘We use the latest data to investigate observational constraints on the new generalized Chaplygin gas (NGCG) model. Using the Markov Chain Monte Carlo method, we constrain the NGCG model with type Ia supernovae from the Union2 set (557 data), the usual baryonic acoustic oscillation (BAO) observation from the spectroscopic Sloan Digital Sky Survey data release 7 galaxy sample, the cosmic mi- crowave background observation from the 7-year Wilkinson Microwave Anisotropy Probe results, newly revised data on H(z), as well as a value of θBAO (Z = 0.55) = (3.90° ±0.38°) for the angular BAO scale. The constraint results for the NGCG model are ωX=-1.0510+0.1563-0.1685(1σ)+0.2226-0.2398(2σ),η=1.0117+0.0469-0.0502(1σ)+0.0693-0.0716(2σ)and ΩX=0.7297+0.0229-0.0276(1σ)+0.0329-0.0402(2σ), which give a rather stringent constraint. From the results, we can see that a phantom model is slightly favored and the proba- bility that energy transfers from dark matter to dark energy is a little larger than the inverse.
基金Projects(51478484,51308551,51678571)supported by the National Natural Science Foundation of ChinaProject(2016zzts063)supported by Fundamental Research Funds for the Central Universities,China
文摘Expansive soil is sensitive to dry and wet environment change. And the volume deformation and inflation pressure of expansive soil may induce to cause the deformation failure of roadbed or many other adverse effects. Aimed at a high-speed railway engineering practice in the newly built Yun-Gui high-speed railway expansive soil section in China, indoor vibration test on a full-scaled new cutting subgrade model is carried out. Based on the established track-subgrade-foundation of expansive soil system dynamic model test platform, dynamic behavior of new cutting subgrade structure under train loads coupling with extreme service environment(dry, raining, and groundwater level rising) is analyzed comparatively. The results show that the subgrade dynamic response is significantly influenced by service conditions and the dynamic response of subgrade gradually becomes stable with the increasing vibration times under various service environment conditions. The vertical dynamic soil stress is related with the depth in an approximate exponential function, and the curves of vertical dynamic soil stress present a "Z" shape distribution along transverse distance. The peak value of dynamic soil stress appears below the rail, and it increases more obviously near the roadbed surface. However, the peak value of dynamic soil stress is little affected outside 5.0 m of center line. The vibration velocity and acceleration are in a quadratic curve with an increase in depth, and the raining and groundwater level rising increase both the vibration velocity and the acceleration. The vertical deformations at different depths are differently affected by service environment in roadbed. The deformation of roadbed increases sharply when the water gets in the foundation of expansive soil, and more than 60% of the total deformation of roadbed occurs in expansive soil foundation. The laid waterproofing and drainage structure layer, which weakens the dynamic stress and improves the track regularity, presents a positive effect on the control deformation of roadbed surface. An improved empirical formula is then proposed to predict the dynamic stress of ballasted tracks subgrade of expansive soil.
文摘According to the basic features of socio economic development in China, the paper retrospects the developmental process of Chinese cities in the 20th century. Based on lots of data and related research achievements, five new patterns of Chinese urban development are pointed out, that is 1) regional disparity of urban development in China is still obvious and large; 2) cities in developed region develop in the form of agglomeration and coordination; 3) spatial layout shape of Chinese cities appears relatively tight, and there exists great outside expansion inclination; 4) the construction of exploitation zone becomes the new important factor of urban development in the 1990s; 5) number increase of cities at county level become the main tide of urban development, but cause the discrete understanding for the concept of urban substantial region, which construct a challenge to urban management. In the end the article puts forward a series thoughts on the future trends and countermeasures of urban development in China.
基金This paper is supported by the Philosophy and Social Science Foundation of Tianjin City (No. TJ05-GL010), and supported by the Two Groups "Binhai New Area Development Study" and "Construction of Philosophy and Social Sciences" in Tianjin City, and also supported by Tianjin Scientific and Technologic Development Strategy.
文摘Ever since involvement of the Binhai New Area into the national development strategy, carrying out highly effective financing promptly will play the pivotal role to implement its economic development strategy smoothly. In this paper, based on nature of regional financing, the descriptive analysis for the financing condition of the Binhai New Area is carried on. And also based on financing restraint theory and the neoclassic investment model, a real diagnosis analysis for the financing constraint condition of the Binhai New Area is studied. Finally, the existed questions in it are pointed out, and propose the correlative improvement countermeasure is put forward.