Due to the shortage of land resources caused by large-scale urban development and construction,old urban areas tend to become the generation places of urban gap space under the background of development and constructi...Due to the shortage of land resources caused by large-scale urban development and construction,old urban areas tend to become the generation places of urban gap space under the background of development and construction without focusing on the utilization of urban stock space.Under the impact of long-term development and new forces,especially the impact of commerce,cities will form self-organized commercial streets for sustainable development,showing the characteristics of disorder and vitality.Based on the urban gap and self-organized commercial street theory,the paper studies the gap space of Zhubao Street in Nanchang,and analyzes the theoretical factors of self-organized commercial street to discuss the characteristics and infl uence of gap space composition,hoping to fi nd out the effective strategy for renovation and renewal.展开更多
We study the effect of electron-phonon (e-ph) interaction on the elastic and inelastic electronic transport of a nanowire connected to two simple rigid leads within the tight-binding and harmonic approximations. The...We study the effect of electron-phonon (e-ph) interaction on the elastic and inelastic electronic transport of a nanowire connected to two simple rigid leads within the tight-binding and harmonic approximations. The model is constructed using Green's function and multi-channel techniques, taking into account the local and nonlocal e-ph interactions. Then, we examine the model for the gapless (simple chain) and gapped (PA-like nanowire) systems. The results show that the tunneling conductance is improved by the e-ph interaction in both local and nonlocal regimes, while for the resonance conductance, the coherent part mainly decreases and the incoherent part increases. At the corresponding energies which depend on the phonon frequency, two dips in the elastic and two peaks in the inelastic conductance spectra appear. The reason is the absorption of the phonon by the electron in transition into inelastic channels.展开更多
Purpose:Secondary displacement represents a frequent complication of conservative treatment of fractures,particularly of the distal radius.The gap space between skin and cast may lead to a certain degree movements and...Purpose:Secondary displacement represents a frequent complication of conservative treatment of fractures,particularly of the distal radius.The gap space between skin and cast may lead to a certain degree movements and this increased mobility might favor redisplacement.The aim of this study was to develop a new 3D method,to measure the gap space in all 3 geometrical planes,and to validate this new technique in a clinical setting of distal radius fractures.Methods:This study applies 3D imaging to measure the space between plaster and skin as a potential factor of secondary displacement and therefore the failure of conservative treatment.We developed and validated a new methodology to analyze and compare different forearm casts made of plaster of Paris and fiberglass.An unpaired t-test was performed to document differences between the investigated parameters between plaster of Paris and fiberglass casts.The significance level was set at p<0.05.Results:In a series of 15 cases,we found the width of the gap space to average 4 mm,being slightly inferior on the radial side.Comparing the two different casting materials,plaster of Paris and fiberglass,we found a significantly larger variance of space under casts made of the first material(p=0.39).A roughness analysis showed also a markedly significantly higher irregularity of the undersurface of plaster of Paris as compared with fiberglass.Conclusion:This study allows for a better understanding of the nature of the"gap space"between cast and skin and will contribute to develop and improve new immobilization techniques and materials.展开更多
This study focuses on the transitions in flow states around two-, three-and four-inline square cylinders under the effect of Reynolds numbers at two different gap spacing values using the lattice Boltzmann method. For...This study focuses on the transitions in flow states around two-, three-and four-inline square cylinders under the effect of Reynolds numbers at two different gap spacing values using the lattice Boltzmann method. For this purpose, Reynolds number is varied in the range 1–130 while two different values of spacing taken into account are gap spacing =2 and 5. Before going to actual problem, the code is tested for flow around a single square cylinder by comparing the results with experimental and numerical results of other researchers, and good agreement is found.The current numerical computations yield that for both spacing values and all combinations of cylinders there exist three different sates of flow depending on Reynolds numbers: steady state, transitional state and unsteady state. It is found that the range of Reynolds numbers for these flow states is different for both spacing values. At gap spacing =2 the range of Reynolds numbers for each flow state decreases by increasing the number of cylinders while at gap spacing =5 opposite trend is observed. The results also show that at gap spacing =2 the reduction in drag force is greater than the corresponding reduction at gap spacing =5. The maximum reduction in drag force is observed at Reynolds numbers =1 at both spacing values. Similarly, at both spacing values and all Reynolds numbers, the maximum reduction in drag force is observed for the case of four-inline square cylinders.展开更多
文摘Due to the shortage of land resources caused by large-scale urban development and construction,old urban areas tend to become the generation places of urban gap space under the background of development and construction without focusing on the utilization of urban stock space.Under the impact of long-term development and new forces,especially the impact of commerce,cities will form self-organized commercial streets for sustainable development,showing the characteristics of disorder and vitality.Based on the urban gap and self-organized commercial street theory,the paper studies the gap space of Zhubao Street in Nanchang,and analyzes the theoretical factors of self-organized commercial street to discuss the characteristics and infl uence of gap space composition,hoping to fi nd out the effective strategy for renovation and renewal.
基金Project supported by the Iranian Nanotechnology Initiativesupported by Shahrekord University through a research fund
文摘We study the effect of electron-phonon (e-ph) interaction on the elastic and inelastic electronic transport of a nanowire connected to two simple rigid leads within the tight-binding and harmonic approximations. The model is constructed using Green's function and multi-channel techniques, taking into account the local and nonlocal e-ph interactions. Then, we examine the model for the gapless (simple chain) and gapped (PA-like nanowire) systems. The results show that the tunneling conductance is improved by the e-ph interaction in both local and nonlocal regimes, while for the resonance conductance, the coherent part mainly decreases and the incoherent part increases. At the corresponding energies which depend on the phonon frequency, two dips in the elastic and two peaks in the inelastic conductance spectra appear. The reason is the absorption of the phonon by the electron in transition into inelastic channels.
文摘Purpose:Secondary displacement represents a frequent complication of conservative treatment of fractures,particularly of the distal radius.The gap space between skin and cast may lead to a certain degree movements and this increased mobility might favor redisplacement.The aim of this study was to develop a new 3D method,to measure the gap space in all 3 geometrical planes,and to validate this new technique in a clinical setting of distal radius fractures.Methods:This study applies 3D imaging to measure the space between plaster and skin as a potential factor of secondary displacement and therefore the failure of conservative treatment.We developed and validated a new methodology to analyze and compare different forearm casts made of plaster of Paris and fiberglass.An unpaired t-test was performed to document differences between the investigated parameters between plaster of Paris and fiberglass casts.The significance level was set at p<0.05.Results:In a series of 15 cases,we found the width of the gap space to average 4 mm,being slightly inferior on the radial side.Comparing the two different casting materials,plaster of Paris and fiberglass,we found a significantly larger variance of space under casts made of the first material(p=0.39).A roughness analysis showed also a markedly significantly higher irregularity of the undersurface of plaster of Paris as compared with fiberglass.Conclusion:This study allows for a better understanding of the nature of the"gap space"between cast and skin and will contribute to develop and improve new immobilization techniques and materials.
文摘This study focuses on the transitions in flow states around two-, three-and four-inline square cylinders under the effect of Reynolds numbers at two different gap spacing values using the lattice Boltzmann method. For this purpose, Reynolds number is varied in the range 1–130 while two different values of spacing taken into account are gap spacing =2 and 5. Before going to actual problem, the code is tested for flow around a single square cylinder by comparing the results with experimental and numerical results of other researchers, and good agreement is found.The current numerical computations yield that for both spacing values and all combinations of cylinders there exist three different sates of flow depending on Reynolds numbers: steady state, transitional state and unsteady state. It is found that the range of Reynolds numbers for these flow states is different for both spacing values. At gap spacing =2 the range of Reynolds numbers for each flow state decreases by increasing the number of cylinders while at gap spacing =5 opposite trend is observed. The results also show that at gap spacing =2 the reduction in drag force is greater than the corresponding reduction at gap spacing =5. The maximum reduction in drag force is observed at Reynolds numbers =1 at both spacing values. Similarly, at both spacing values and all Reynolds numbers, the maximum reduction in drag force is observed for the case of four-inline square cylinders.