The paper that follows analyzes the basic directions of the Larissa’s Sustainable Urban Mobility Plan and aims at developing a first kind of assessment in relation to whether the plan has achieved its main objectives...The paper that follows analyzes the basic directions of the Larissa’s Sustainable Urban Mobility Plan and aims at developing a first kind of assessment in relation to whether the plan has achieved its main objectives and how it interacts with the existing urban plot.First results show that emphasis is given to“alternative and more environmentally friendly kinds of circulation”and the emergence of the“neighborhood”as the main spatial scale of reference.The plan tries to manage the traffic issue of the city center,unsuccessfully so far.However,it does not take into account the spatial dimension of land uses.The networking of important functions and service providers is not a priority and,as a general conclusion,the plan does not serve the principle of integration neither guarantees the universal access to basic destinations and services.The paper argues that the plan could be improved by introducing a“bottom-up”design process,incorporating elements of the new and emerging agenda of“urban problems”(e.g.resilience targets)and moving away from the unification of“embellishment”and face the main issues of the real city.Those should be the priorities of the so called“combined and integrated design and planning practices”,which are now missing.展开更多
Sustainable mobility planning is an emerging planning concept, largely applied in European and American cities during the last two decades, as a means to achieve more efficient and sustainable cities regarding the cea...Sustainable mobility planning is an emerging planning concept, largely applied in European and American cities during the last two decades, as a means to achieve more efficient and sustainable cities regarding the ceasing of the major threats to urban environment, namely： climate change, accidents, traffic saturation, air and noise pollution, car dependency and domination in the public space. Municipality of Piraeus is a developing autonomous commercial and business center, characterized by high density housing, narrow street geometric characteristics and the port presence. Aim of this paper is to present its recent sustainable mobility plan by putting special emphasis on the strategic plan for a cycling network. The key principles of its methodological development are demonstrated along with the strategic enhancement of walking and multimodal transport services. The main objective is to integrate cycling in mobility policies applied by the described plan in Piraeus.展开更多
Mobile anchors are widely used for localization in WSNs.However,special properties over 3D terrains limit the implementation of them.In this paper,a novel 3D localization algorithm is proposed,called 3 DT-PP,which uti...Mobile anchors are widely used for localization in WSNs.However,special properties over 3D terrains limit the implementation of them.In this paper,a novel 3D localization algorithm is proposed,called 3 DT-PP,which utilizes path planning of mobile anchors over complex 3 D terrains,and simulations based upon the model of mountain surface network are conducted.The simulation results show that the algorithm decreases the position error by about 91%,8.7%and lowers calculation overhead by about 75%,1.3%,than the typical state-of-the-art localization algorithm(i.e.,'MDS-MAP','Landscape-3D').Thus,our algorithm is more potential in practical WSNs which are the characteristic of limited energy and 3D deployment.展开更多
Nikuradse roughness(ks) is very important in the sediment transport prediction because it is related to the evaluations of the velocity distribution, shear stress and erosion depth. Dimensionless Nikuradse roughness(k...Nikuradse roughness(ks) is very important in the sediment transport prediction because it is related to the evaluations of the velocity distribution, shear stress and erosion depth. Dimensionless Nikuradse roughness(ks/D,where D is the sediment diameter) is usually given 1–2.5 on the immobile plan bed or at low shear stress. But it behaves differently on the mobile plan bed at high shear stress with much sediment picked up to movement when the Shields parameter(Θ) is larger than 0.8–1.0. The effective Nikuradse roughness on the mobile plan bed was derived indirectly from the erosion depth correlated to the mobile plan bed thickness considering the mass conservation in the present study. The proposed erosion depth confirmed the relation to the Shields parameters with an extra factor consisting of suspended sediment and its damping to turbulence. The decrement of the erosion depth caused by the increment of the sediment diameter at large shear stress was obtained, which was usually absent in classical empirical formulas based on the bedload theory. Good agreement with experiments was achieved by the present prediction of the Nikuradse roughness, erosion depth and sediment transport rate. Discussion was mainly focused on the prediction improvement caused by considering the impact of suspended sediment and its damping to turbulence.展开更多
文摘The paper that follows analyzes the basic directions of the Larissa’s Sustainable Urban Mobility Plan and aims at developing a first kind of assessment in relation to whether the plan has achieved its main objectives and how it interacts with the existing urban plot.First results show that emphasis is given to“alternative and more environmentally friendly kinds of circulation”and the emergence of the“neighborhood”as the main spatial scale of reference.The plan tries to manage the traffic issue of the city center,unsuccessfully so far.However,it does not take into account the spatial dimension of land uses.The networking of important functions and service providers is not a priority and,as a general conclusion,the plan does not serve the principle of integration neither guarantees the universal access to basic destinations and services.The paper argues that the plan could be improved by introducing a“bottom-up”design process,incorporating elements of the new and emerging agenda of“urban problems”(e.g.resilience targets)and moving away from the unification of“embellishment”and face the main issues of the real city.Those should be the priorities of the so called“combined and integrated design and planning practices”,which are now missing.
文摘Sustainable mobility planning is an emerging planning concept, largely applied in European and American cities during the last two decades, as a means to achieve more efficient and sustainable cities regarding the ceasing of the major threats to urban environment, namely： climate change, accidents, traffic saturation, air and noise pollution, car dependency and domination in the public space. Municipality of Piraeus is a developing autonomous commercial and business center, characterized by high density housing, narrow street geometric characteristics and the port presence. Aim of this paper is to present its recent sustainable mobility plan by putting special emphasis on the strategic plan for a cycling network. The key principles of its methodological development are demonstrated along with the strategic enhancement of walking and multimodal transport services. The main objective is to integrate cycling in mobility policies applied by the described plan in Piraeus.
基金Supported by the Important National Science and Technology Specific Project of China(No.20112X03002-002-03)the National NatureScience Foundation of China(No.61133016,61163066)
文摘Mobile anchors are widely used for localization in WSNs.However,special properties over 3D terrains limit the implementation of them.In this paper,a novel 3D localization algorithm is proposed,called 3 DT-PP,which utilizes path planning of mobile anchors over complex 3 D terrains,and simulations based upon the model of mountain surface network are conducted.The simulation results show that the algorithm decreases the position error by about 91%,8.7%and lowers calculation overhead by about 75%,1.3%,than the typical state-of-the-art localization algorithm(i.e.,'MDS-MAP','Landscape-3D').Thus,our algorithm is more potential in practical WSNs which are the characteristic of limited energy and 3D deployment.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.51836010 and 51609244)the National Science-Technology Support Plan Projects(Grant No.2015BAD20B01)
文摘Nikuradse roughness(ks) is very important in the sediment transport prediction because it is related to the evaluations of the velocity distribution, shear stress and erosion depth. Dimensionless Nikuradse roughness(ks/D,where D is the sediment diameter) is usually given 1–2.5 on the immobile plan bed or at low shear stress. But it behaves differently on the mobile plan bed at high shear stress with much sediment picked up to movement when the Shields parameter(Θ) is larger than 0.8–1.0. The effective Nikuradse roughness on the mobile plan bed was derived indirectly from the erosion depth correlated to the mobile plan bed thickness considering the mass conservation in the present study. The proposed erosion depth confirmed the relation to the Shields parameters with an extra factor consisting of suspended sediment and its damping to turbulence. The decrement of the erosion depth caused by the increment of the sediment diameter at large shear stress was obtained, which was usually absent in classical empirical formulas based on the bedload theory. Good agreement with experiments was achieved by the present prediction of the Nikuradse roughness, erosion depth and sediment transport rate. Discussion was mainly focused on the prediction improvement caused by considering the impact of suspended sediment and its damping to turbulence.
