Missouri University of Science and Technology

About: Missouri University of Science and Technology is a education organization based out in Rolla, Missouri, United States. It is known for research contribution in the topics: Control theory & Artificial neural network. The organization has 9380 authors who have published 21161 publications receiving 462544 citations. The organization is also known as: Missouri S&T & University of Missouri–Rolla.

Location-Aware Collaborative Filtering for QoS-Based Service Recommendation

Abstract: Collaborative filtering is one of widely used Web service recommendation techniques. In QoS-based Web service recommendation, predicting missing QoS values of services is often required. There have been several methods of Web service recommendation based on collaborative filtering, but seldom have they considered locations of both users and services in predicting QoS values of Web services. Actually, locations of users or services do have remarkable impacts on values of QoS factors, such as response time, throughput, and reliability. In this paper, we propose a method of location-aware collaborative filtering to recommend Web services to users by incorporating locations of both users and services. Different from existing user-based collaborative filtering for finding similar users for a target user, instead of searching entire set of users, we concentrate on users physically near to the target user. Similarly, we also modify existing service similarity measurement of collaborative filtering by employing service location information. After finding similar users and services, we use the similarity measurement to predict missing QoS values based on a hybrid collaborative filtering technique. Web service candidates with the top QoS values are recommended to users. To validate our method, we conduct series of large-scale experiments based on a real-world Web service QoS dataset. Experimental results show that the location-aware method improves performance of recommendation significantly.

Microstructural modification of as-cast Al-Si-Mg alloy by friction stir processing

Abstract: Friction stir processing (FSP) has been applied to cast aluminum alloy A356 plates to enhance the mechanical properties through microstructural refinement and homogenization. The effect of tool geometry and FSP parameters on resultant microstructure and mechanical properties was investigated. The FSP broke up and dispersed the coarse acicular Si particles creating a uniform distribution of Si particles in the aluminum matrix with significant microstructural refinement. Further, FSP healed the casting porosity. These microstructural changes led to a significant improvement in both strength and ductility. Higher tool rotation rate was the most effective parameter to refine coarse Si particles, heal the casting porosity, and consequently increase strength. The effect of tool geometry was complicated and no systematic trend was observed. For a standard pin design, maximum strength was achieved at a tool rotation rate of 900 rpm and traverse speed of 203 mm/min. Post-FSP aging increased strength for materials processed at higher tool rotation rates of 700 to 1100 rpm, but exerted only a marginal effect on samples prepared at the lower rotation rate of 300 rpm. Two-pass FSP with 100 pct overlapping passes resulted in higher strength for both as-FSP and post-FSP aged conditions.

Phytovolatilization of Organic Contaminants

Abstract: Plants can interact with a variety of organic compounds, and thereby affect the fate and transport of many environmental contaminants. Volatile organic compounds may be volatilized from stems or leaves (direct phytovolatilization) or from soil due to plant root activities (indirect phytovolatilization). Fluxes of contaminants volatilizing from plants are important across scales ranging from local contaminant spills to global fluxes of methane emanating from ecosystems biochemically reducing organic carbon. In this article past studies are reviewed to clearly differentiate between direct- and indirect-phytovolatilization and we discuss the plant physiology driving phytovolatilization in different ecosystems. Current measurement techniques are also described, including common difficulties in experimental design. We also discuss reports of phytovolatilization in the literature, finding that compounds with low octanol-air partitioning coefficients are more likely to be phytovolatilized (log KOA < 5). Reports ...