SV/IEEE 802.15.3a model has been the standard model for Ultra-wide bandwidth (UWB) indoor non-line-of-sight (NLOS) wireless propagation,but for line-of-sight (LOS) case,it is not well defined. In this paper,a new stat...SV/IEEE 802.15.3a model has been the standard model for Ultra-wide bandwidth (UWB) indoor non-line-of-sight (NLOS) wireless propagation,but for line-of-sight (LOS) case,it is not well defined. In this paper,a new statistical distribution model exclusively used for LOS environment is proposed based on investigation of the experimental data. By reducing the number of the visible random arriving clusters,the model itself and the parameters estimating of the corresponding model are simplified in comparison with SV/IEEE 802.15.3a model. The simulation result indicates that the proposed model is more accurate in modeling small-scale LOS environment than SV/IEEE 802.15.3a model when considering cumulative distribution functions (CDFs) for the three key channel impulse response (CIR) statistics.展开更多
The agricultural sector is often considered to be the largest water consumer and the policy aimed at saving irrigation water exists across Europe. The flip-side of such policy, however, is the disappearance of traditi...The agricultural sector is often considered to be the largest water consumer and the policy aimed at saving irrigation water exists across Europe. The flip-side of such policy, however, is the disappearance of traditional irrigation canals since farmers are encouraged to turn to drip irrigation and overhead irrigation gradually. Given this, we would like to argue that traditional irrigation canals need to be reexamined. Such canals are not only built aquatic infrastructure, they are also the product of a culture and social relationship with water in the Mediterranean region. Canals form a complex system which is driven by environmental, economic and social factors. Our sociological and environmental research in Provence （and around the Durance basin more specifically） points up how the very dense territorial network of gravity-fed canals is useful in water management, as well as in other shared uses over the long-term. The findings underscore the positive environmental role played by these historical and anthropogenic constructions. They contribute to refilling the aquifer and also act as a valuable environmental good and service （e.g., run-off regulation, biodiversity, landscape, recreation, etc.）. Further, several local actors have underscored their role as part of an intangible cultural heritage and as important for the area＇s economic and social development. Such canals play a central role in sustainable development since beyond their productive role in agriculture, they play a social role （new uses） and an ecological role （as reservoirs for biodiversity and ecological corridors）.展开更多
基金the Key Program of National Natural Science Foundation of China(Grant No.60432040).
文摘SV/IEEE 802.15.3a model has been the standard model for Ultra-wide bandwidth (UWB) indoor non-line-of-sight (NLOS) wireless propagation,but for line-of-sight (LOS) case,it is not well defined. In this paper,a new statistical distribution model exclusively used for LOS environment is proposed based on investigation of the experimental data. By reducing the number of the visible random arriving clusters,the model itself and the parameters estimating of the corresponding model are simplified in comparison with SV/IEEE 802.15.3a model. The simulation result indicates that the proposed model is more accurate in modeling small-scale LOS environment than SV/IEEE 802.15.3a model when considering cumulative distribution functions (CDFs) for the three key channel impulse response (CIR) statistics.
文摘The agricultural sector is often considered to be the largest water consumer and the policy aimed at saving irrigation water exists across Europe. The flip-side of such policy, however, is the disappearance of traditional irrigation canals since farmers are encouraged to turn to drip irrigation and overhead irrigation gradually. Given this, we would like to argue that traditional irrigation canals need to be reexamined. Such canals are not only built aquatic infrastructure, they are also the product of a culture and social relationship with water in the Mediterranean region. Canals form a complex system which is driven by environmental, economic and social factors. Our sociological and environmental research in Provence （and around the Durance basin more specifically） points up how the very dense territorial network of gravity-fed canals is useful in water management, as well as in other shared uses over the long-term. The findings underscore the positive environmental role played by these historical and anthropogenic constructions. They contribute to refilling the aquifer and also act as a valuable environmental good and service （e.g., run-off regulation, biodiversity, landscape, recreation, etc.）. Further, several local actors have underscored their role as part of an intangible cultural heritage and as important for the area＇s economic and social development. Such canals play a central role in sustainable development since beyond their productive role in agriculture, they play a social role （new uses） and an ecological role （as reservoirs for biodiversity and ecological corridors）.
