A remote antenna unit （RAU） selection model is presented, and two kinds of handoffs, intra-cell handoff （HO） and inter-cell HO, are defined in distributed mobile communications systems （DAS）. After that, an inte...A remote antenna unit （RAU） selection model is presented, and two kinds of handoffs, intra-cell handoff （HO） and inter-cell HO, are defined in distributed mobile communications systems （DAS）. After that, an inter-cell HO model is proposed, in which the average power of the active set （AS） is used to predict the position of the mobile station （MS）. The total power of the AS and the handoff set （HOS） are utilized to determine whether an inter-cell HO is necessary. Furthermore, the relationship between HO parameters and performance metrics is studied in detail based on RAU selection. Simulation results show that both the intra-cell HO and the inter-cell HO can achieve oerfect performance by aoprooriate settings of HO parameters.展开更多
This paper briefs the configuration and performance of large size gas turbines and their composed combined cycle power plants designed and produced by four large renown gas turbine manufacturing firms in the world, pr...This paper briefs the configuration and performance of large size gas turbines and their composed combined cycle power plants designed and produced by four large renown gas turbine manufacturing firms in the world, providing reference for the relevant sectors and enterprises in importing advanced gas turbines and technologies.展开更多
Context:Without clear understanding of the units used for ecosystem service(ES)mapping,ES assessment accuracy and the practical application of ES knowledge will be hampered.Method:We systematically reviewed 106 studie...Context:Without clear understanding of the units used for ecosystem service(ES)mapping,ES assessment accuracy and the practical application of ES knowledge will be hampered.Method:We systematically reviewed 106 studies over the past 11 years to explore the type,characteristic pattern and deficiencies of mapping units.Result:We proposed that ES mapping units can be categorized into minimal unit for assessing ESs using corresponding indicators and methods,and aggregated unit for analysis and application based on research objectives,and classified the mapping units into five common types.Of the 12 characterizing variables of ES mapping studies,some have been shown to introduce a difference in the selection of mapping units and to exhibit characteristic patterns.We also found that the accuracy of ES assessments based on minimal units was lacking,and aggregated units were insufficient to establish a link between ES knowledge and practice.Conclusion:Herein,we propose possible solutions such as the use of fine spatial resolution grids and the introduction of additional data beyond land cover as supplements to improve the assessment accuracy.To enhance the availability of the results for practice,aggregated units connected with urban planning units should be established at a spatial level suitable for urban management.展开更多
基金The National Natural Science Foundation of China(No60496311)
文摘A remote antenna unit （RAU） selection model is presented, and two kinds of handoffs, intra-cell handoff （HO） and inter-cell HO, are defined in distributed mobile communications systems （DAS）. After that, an inter-cell HO model is proposed, in which the average power of the active set （AS） is used to predict the position of the mobile station （MS）. The total power of the AS and the handoff set （HOS） are utilized to determine whether an inter-cell HO is necessary. Furthermore, the relationship between HO parameters and performance metrics is studied in detail based on RAU selection. Simulation results show that both the intra-cell HO and the inter-cell HO can achieve oerfect performance by aoprooriate settings of HO parameters.
文摘This paper briefs the configuration and performance of large size gas turbines and their composed combined cycle power plants designed and produced by four large renown gas turbine manufacturing firms in the world, providing reference for the relevant sectors and enterprises in importing advanced gas turbines and technologies.
基金This work was supported by the China National R&D Program under grant number 2017YFC0505705.
文摘Context:Without clear understanding of the units used for ecosystem service(ES)mapping,ES assessment accuracy and the practical application of ES knowledge will be hampered.Method:We systematically reviewed 106 studies over the past 11 years to explore the type,characteristic pattern and deficiencies of mapping units.Result:We proposed that ES mapping units can be categorized into minimal unit for assessing ESs using corresponding indicators and methods,and aggregated unit for analysis and application based on research objectives,and classified the mapping units into five common types.Of the 12 characterizing variables of ES mapping studies,some have been shown to introduce a difference in the selection of mapping units and to exhibit characteristic patterns.We also found that the accuracy of ES assessments based on minimal units was lacking,and aggregated units were insufficient to establish a link between ES knowledge and practice.Conclusion:Herein,we propose possible solutions such as the use of fine spatial resolution grids and the introduction of additional data beyond land cover as supplements to improve the assessment accuracy.To enhance the availability of the results for practice,aggregated units connected with urban planning units should be established at a spatial level suitable for urban management.
