A new finite element model for single-layered strand was investigated for accurate and efficient mechanical behavior analysis.Mathematical model was created by sectional path-nodes sweeping and dynamic node-beam mappi...A new finite element model for single-layered strand was investigated for accurate and efficient mechanical behavior analysis.Mathematical model was created by sectional path-nodes sweeping and dynamic node-beam mapping.Geometric relations between nodes in center core wire and helical wires were deduced in tension and bending incorporating material elasticity theory and deformation geometrical compatibility.Based on Timoshenko beam theory,strand of a pitch length was modeled with specific material,geometric parameters and synthesized constraint equations defined in ANSYS software,and predetermined load cases were performed.The obtained results show that discrepancies between suggested method and Costello theory do not exceed 1.51% in tension and 6.21% in bending,which verifies the correctness and accuracy of the suggested finite element model in predicting mechanical behavior of single-layered wire strand.展开更多
The geometric and physical analysis methods are conventional methods for the derivation of skeleton lines in the fields of cartography,digital photogrammetry,and related areas.This paper proposes a stepwise approach t...The geometric and physical analysis methods are conventional methods for the derivation of skeleton lines in the fields of cartography,digital photogrammetry,and related areas.This paper proposes a stepwise approach that uses the physical analysis method in the first stage and the geometric analysis method in the subsequent stage.The physical analysis method analyses the terrain globally to obtain a rough set of skeleton lines for a terrain surface.The rough skeleton lines help to structure the ordering of feature points by the geometric analysis method.展开更多
This paper proposes that organizational performance improvement could be achieved through improving the relationship between suppliers and customers. Accordingly, the paper proposes that performance could be improved ...This paper proposes that organizational performance improvement could be achieved through improving the relationship between suppliers and customers. Accordingly, the paper proposes that performance could be improved by properly managing differences （gaps） that are usually found between customers＇ expectations and of suppliers perception with respect to services delivered. The paper also proposes that gaps in the relationship between customers and suppliers could be analyzed using mapping techniques. The paper points to the possibility of finding perception gaps and expectation gaps in the interrelated value attributes of goods and/or services; namely quality, cost, and time of delivery of goods or services to customers. In addition, the paper suggests that those gaps may impact on the performance from the perspectives of quality, cost, and speed of delivery of the service. It is envisaged that this research could assist management in controlling cost and avoid wastage and improve organizational performance.展开更多
Spatial clustering is widely used in many fields such as WSN (Wireless Sensor Networks), web clustering, remote sensing and so on for discovery groups and to identify interesting distributions in the underlying databa...Spatial clustering is widely used in many fields such as WSN (Wireless Sensor Networks), web clustering, remote sensing and so on for discovery groups and to identify interesting distributions in the underlying database. By discussing the relationships between the optimal clustering and the initial seeds, a clustering validity index and the principle of seeking initial seeds were proposed, and on this principle we recommend an initial seed-seeking strategy: SSPG (Single-Shortest-Path Graph). With SSPG strategy used in clustering algorithms, we find that the result of clustering is optimized with more probability. At the end of the paper, according to the combinational theory of optimization, a method is proposed to obtain optimal reference k value of cluster number, and is proven to be efficient.展开更多
基金Project(2009J007)supported by Science and Technology Department of Railway Ministry of ChinaProject(U1134203)supported by Joint Fund of High-speed Railway Fundamental Research,China
文摘A new finite element model for single-layered strand was investigated for accurate and efficient mechanical behavior analysis.Mathematical model was created by sectional path-nodes sweeping and dynamic node-beam mapping.Geometric relations between nodes in center core wire and helical wires were deduced in tension and bending incorporating material elasticity theory and deformation geometrical compatibility.Based on Timoshenko beam theory,strand of a pitch length was modeled with specific material,geometric parameters and synthesized constraint equations defined in ANSYS software,and predetermined load cases were performed.The obtained results show that discrepancies between suggested method and Costello theory do not exceed 1.51% in tension and 6.21% in bending,which verifies the correctness and accuracy of the suggested finite element model in predicting mechanical behavior of single-layered wire strand.
文摘The geometric and physical analysis methods are conventional methods for the derivation of skeleton lines in the fields of cartography,digital photogrammetry,and related areas.This paper proposes a stepwise approach that uses the physical analysis method in the first stage and the geometric analysis method in the subsequent stage.The physical analysis method analyses the terrain globally to obtain a rough set of skeleton lines for a terrain surface.The rough skeleton lines help to structure the ordering of feature points by the geometric analysis method.
文摘This paper proposes that organizational performance improvement could be achieved through improving the relationship between suppliers and customers. Accordingly, the paper proposes that performance could be improved by properly managing differences （gaps） that are usually found between customers＇ expectations and of suppliers perception with respect to services delivered. The paper also proposes that gaps in the relationship between customers and suppliers could be analyzed using mapping techniques. The paper points to the possibility of finding perception gaps and expectation gaps in the interrelated value attributes of goods and/or services; namely quality, cost, and time of delivery of goods or services to customers. In addition, the paper suggests that those gaps may impact on the performance from the perspectives of quality, cost, and speed of delivery of the service. It is envisaged that this research could assist management in controlling cost and avoid wastage and improve organizational performance.
基金Supported by the National Natural Science Foundation of China （No.60502028, No. 90204008）.
文摘Spatial clustering is widely used in many fields such as WSN (Wireless Sensor Networks), web clustering, remote sensing and so on for discovery groups and to identify interesting distributions in the underlying database. By discussing the relationships between the optimal clustering and the initial seeds, a clustering validity index and the principle of seeking initial seeds were proposed, and on this principle we recommend an initial seed-seeking strategy: SSPG (Single-Shortest-Path Graph). With SSPG strategy used in clustering algorithms, we find that the result of clustering is optimized with more probability. At the end of the paper, according to the combinational theory of optimization, a method is proposed to obtain optimal reference k value of cluster number, and is proven to be efficient.
