Microstructures and mechanical properties of Nd : YAG laser welded transformation induced plasticity (TRIP) steel with tensile strength of 645 MPa were studied. Due to high cooling speed of laser welding, the weld ...Microstructures and mechanical properties of Nd : YAG laser welded transformation induced plasticity (TRIP) steel with tensile strength of 645 MPa were studied. Due to high cooling speed of laser welding, the weld metal mainly consists of martensite different from the base metal, which is composed of ferrite matrix with bainite and a little retained austenite. Therefore, the weld metal has maximum hardness at welded joint. The yield strength and tensile strength of welded specimens tested perpendicular to weld line were almost equal to those of the base metal. But the yield strength and tensile strength of welded specimens tested parallel with weld line were a little higher than those of the base metal. The formability of laser welded TRIP steel was decreased compared with that of the base metal.展开更多
Trust, as a major part of human interactions, plays an important role in helping users collect reliable infor-mation and make decisions. However, in reality, user-specified trust relations are often very sparse and fo...Trust, as a major part of human interactions, plays an important role in helping users collect reliable infor-mation and make decisions. However, in reality, user-specified trust relations are often very sparse and follow a power law distribution; hence inferring unknown trust relations attracts increasing attention in recent years. Social theories are frameworks of empirical evidence used to study and interpret social phenomena from a sociological perspective, while social networks reflect the correlations of users in real world; hence, making the principle, rules, ideas and methods of social theories into the analysis of social networks brings new opportunities for trust prediction. In this paper, we investigate how to exploit homophily and social status in trust prediction by modeling social theories. We first give several methods to compute homophily coe?cient and status coe?cient, then provide a principled way to model trust prediction mathe-matically, and propose a novel framework, hsTrust, which incorporates homophily theory and status theory. Experimental results on real-world datasets demonstrate the effectiveness of the proposed framework. Further experiments are conducted to understand the importance of homophily theory and status theory in trust prediction.展开更多
文摘Microstructures and mechanical properties of Nd : YAG laser welded transformation induced plasticity (TRIP) steel with tensile strength of 645 MPa were studied. Due to high cooling speed of laser welding, the weld metal mainly consists of martensite different from the base metal, which is composed of ferrite matrix with bainite and a little retained austenite. Therefore, the weld metal has maximum hardness at welded joint. The yield strength and tensile strength of welded specimens tested perpendicular to weld line were almost equal to those of the base metal. But the yield strength and tensile strength of welded specimens tested parallel with weld line were a little higher than those of the base metal. The formability of laser welded TRIP steel was decreased compared with that of the base metal.
基金This work is supported by the National Natural Science Foundation of China under Grant No. 61300148, the Scientific and Technological Break-Through Program of Jilin Province of China under Grant No. 20130206051GX, and the Science and Technology Development Program of Jilin Province of China under Grant No. 20130522112JH.
文摘Trust, as a major part of human interactions, plays an important role in helping users collect reliable infor-mation and make decisions. However, in reality, user-specified trust relations are often very sparse and follow a power law distribution; hence inferring unknown trust relations attracts increasing attention in recent years. Social theories are frameworks of empirical evidence used to study and interpret social phenomena from a sociological perspective, while social networks reflect the correlations of users in real world; hence, making the principle, rules, ideas and methods of social theories into the analysis of social networks brings new opportunities for trust prediction. In this paper, we investigate how to exploit homophily and social status in trust prediction by modeling social theories. We first give several methods to compute homophily coe?cient and status coe?cient, then provide a principled way to model trust prediction mathe-matically, and propose a novel framework, hsTrust, which incorporates homophily theory and status theory. Experimental results on real-world datasets demonstrate the effectiveness of the proposed framework. Further experiments are conducted to understand the importance of homophily theory and status theory in trust prediction.