Farmland and primary farmland protection are important contents of land management and land use planning of China. In the new round of land use planning and database construction, primary farmland protection zones are...Farmland and primary farmland protection are important contents of land management and land use planning of China. In the new round of land use planning and database construction, primary farmland protection zones are required to have high integrity and connectivity. Using landscape pattern indexes, the integrity and connectivity of primary farmland protection zones was studied in Licheng District of Jinan City. The results showed that, except patch area standard deviation, the other indexes including average patch area, patch area variation coefficient, patch edge density, largest patch index, and mean euclidean nearest-neighbor, all indicate high connectivity of primary farmland protection zones after layout adjustment. A simple and convenient method for identifying the integrity and connectivity of primary farmland protection zones was supplied.展开更多
The distributed hierarchical control based on multi-agent system(MAS) is the main control method of micro-grids.By allowing more flexible interactions between computing components and their physical environments,cyber...The distributed hierarchical control based on multi-agent system(MAS) is the main control method of micro-grids.By allowing more flexible interactions between computing components and their physical environments,cyber physical system(CPS) presents a new approach for the distributed hierarchical engineering system,with micro-grids included.The object of this paper is to integrate the CPS concept with MAS technology and propose a new control framework for micro-grids.With the analysis of the operating mode and control method of micro-grids,the cyber physical control concepts of ontologybased semantic agent are discussed.Then an MAS-based architecture of cyber physical micro-grid system and an intelligent electronic device(IED) function structure are proposed.Finally,in order to operate and test the cyber physical micro-grid concept,an integrated simulation model is presented.展开更多
Integral abutment bridges are becoming rather common, due to the durability problems of bearings and expansion joints. At the same time, among short- and medium-span bridges, multi-beam steel-concrete composite deck w...Integral abutment bridges are becoming rather common, due to the durability problems of bearings and expansion joints. At the same time, among short- and medium-span bridges, multi-beam steel-concrete composite deck with hot-rolled girder is an economical and interesting alternative to traditional pre-stressed concrete solutions. The two concepts can be linked together to design integral steel-concrete composite bridges with the benefits of two typologies. The most critical aspect for these bridges is usually the joints between deck and piers or abutments. In this paper, an innovative beam-to-pier joint is proposed and a theoretical and experimental study is introduced and discussed. The analyzed connection is aimed at combining general ease of construction with a highly simplified assembly procedure and a good transmission of hogging and sagging moment at the supports in continuous beams. For this purpose, the traditional shear studs, used at the interface be- tween steel beam and upper concrete slab, are also used at the ends of steel profiles welded horizontally to the end plates. To better understand the behaviour of this kind of joints and the roles played by different components, three large-scale specimens were tested and an FE model was implemented. The theoretical and experimental results confirmed the po- tential of the proposed connection for practical applications and indicated the way to improve its structural behaviour.展开更多
基金Sponsored by Land Use Planning Database Construction Program of Licheng District,Jinan City
文摘Farmland and primary farmland protection are important contents of land management and land use planning of China. In the new round of land use planning and database construction, primary farmland protection zones are required to have high integrity and connectivity. Using landscape pattern indexes, the integrity and connectivity of primary farmland protection zones was studied in Licheng District of Jinan City. The results showed that, except patch area standard deviation, the other indexes including average patch area, patch area variation coefficient, patch edge density, largest patch index, and mean euclidean nearest-neighbor, all indicate high connectivity of primary farmland protection zones after layout adjustment. A simple and convenient method for identifying the integrity and connectivity of primary farmland protection zones was supplied.
基金National Natural Science Foundation of China(No.51477097)the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,China(No.LAPS13009)National High-Technology Research and Development Program of China(863 Program)(No.2013BAA01B04)
文摘The distributed hierarchical control based on multi-agent system(MAS) is the main control method of micro-grids.By allowing more flexible interactions between computing components and their physical environments,cyber physical system(CPS) presents a new approach for the distributed hierarchical engineering system,with micro-grids included.The object of this paper is to integrate the CPS concept with MAS technology and propose a new control framework for micro-grids.With the analysis of the operating mode and control method of micro-grids,the cyber physical control concepts of ontologybased semantic agent are discussed.Then an MAS-based architecture of cyber physical micro-grid system and an intelligent electronic device(IED) function structure are proposed.Finally,in order to operate and test the cyber physical micro-grid concept,an integrated simulation model is presented.
文摘Integral abutment bridges are becoming rather common, due to the durability problems of bearings and expansion joints. At the same time, among short- and medium-span bridges, multi-beam steel-concrete composite deck with hot-rolled girder is an economical and interesting alternative to traditional pre-stressed concrete solutions. The two concepts can be linked together to design integral steel-concrete composite bridges with the benefits of two typologies. The most critical aspect for these bridges is usually the joints between deck and piers or abutments. In this paper, an innovative beam-to-pier joint is proposed and a theoretical and experimental study is introduced and discussed. The analyzed connection is aimed at combining general ease of construction with a highly simplified assembly procedure and a good transmission of hogging and sagging moment at the supports in continuous beams. For this purpose, the traditional shear studs, used at the interface be- tween steel beam and upper concrete slab, are also used at the ends of steel profiles welded horizontally to the end plates. To better understand the behaviour of this kind of joints and the roles played by different components, three large-scale specimens were tested and an FE model was implemented. The theoretical and experimental results confirmed the po- tential of the proposed connection for practical applications and indicated the way to improve its structural behaviour.
