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For the past ten years, the Intelligent Robotics Laboratory (IRL) at Vanderbilt University has been developing service robots that interact naturally, closely and safely with human beings. Two main issues for research have arisen from this prior work. The first is how to achieve a high level of interaction between the human and robot. The result has been the philosophy of human directed local autonomy (HuDL), a guiding principle for research, design, and implementation of service robots. The human‐robot relationship we seek to achieve is symbiotic in the sense that both the human and the robot work together to achieve goals, for example as aids to the elderly or disabled. The second issue is the general problem of system integration, with a specific focus on integrating humans into the service robotic system. This issue has led to the development of the Intelligent Machine Architecture (IMA), a novel software architecture specifically designed to simplify the integration of the many diverse algorithms, sensors, and actuators necessary for intelligent interactive service robots.

Materials commonly involve microstructure. Clay is a microinhomogeneous material with nanoscale microstructure. Key issues to understand the behavior of such a finely microinhomogeneous material are as follows: the microstructure is characterized in detail, the local distribution of material properties is identified by experiment or simulation, and the microscale characteristics are related to the macroscale behavior by a seamless manner. For characterizing a microstructure of bentonite, we introduce a conforcal laser scanning microscope (CLSM) together with SEM. By CLSM we can specify a 3D configuration under atmospheric condition. Properties of water‐saturated bentonite are mainly controlled by hydrated montmorillonite, which is the major clay mineral of bentonite. Smectite minerals including montmorillonite are extremely fine and poorly crystallized, so it is difficult to determine the properties by experiment. We inquire into the physicochemical properties by a molecular dynamics simulation method. Then, we develop a multiscale homogenization method to extend the microscopic characteristics to the macroscopic behavior. We show numerical examples of a diffusion problem.

The paper aims to clarify the relationship between the micro-structures of porous media and the coefficient of permeability. Most materials involve different types of defects like caves, pores and cracks, which are important characters of porous media and have a great influence on the physical properties of materials. To study the seepage mechanical characteristics of damaged porous media, the constitutive model of porous media dealing with coupled modeling of pores damage and its impact on permeability property of a deforming media was studied in this paper.

The paper opted for an exploratory study using the approach of continuum damage mechanics (CDM).

The paper provides some new insights on the fluid dynamics of porous media. The dynamic evolution model of permeability coefficient established in this paper can be used to model the fluid flow problems in damaged porous media. Moreover, the modified Darcy's law developed in this paper is considered to be an extension of the Darcy's law for fluid flow and seepage in a porous medium.

Owing to the limitations of time, conditions, funds, etc., the research results should be subject to multifaceted experiments before their innovative significance can be fully verified.

The paper includes implications for the development of fluid dynamics of porous media.

This paper fulfils an identified need to study the relationship between the micro-structures of porous media and the coefficient of permeability.

The purpose of this paper is to apply lattice Boltzmann equation method (LBM) with multiple relaxation time (MRT) model, to investigate lid‐driven flow in a three‐dimensional (3D), rectangular cavity, and compare the results with flow in an equivalent two‐dimensional (2D) cavity.

The second‐order MRT model is implemented in a 3D LBM code. The flow structure in cavities of different aspect ratios (0.25‐4) and Reynolds numbers (0.01‐1000) is investigated. The LBM simulation results are compared with those from numerical solution of Navier‐Stokes (NS) equations and with available experimental data.

The 3D simulations demonstrate that 2D models may predict the flow structure reasonably well at low Reynolds numbers, but significant differences with experimental data appear at high Reynolds numbers. Such discrepancy between 2D and 3D results are attributed to the effect of boundary layers near the side‐walls in transverse direction (in 3D), due to which the vorticity in the core‐region is weakened in general. Secondly, owing to the vortex stretching effect present in 3D flow, the vorticity in the transverse plane intensifies whereas that in the lateral plane decays, with increase in Reynolds number. However, on the symmetry‐plane, the flow structure variation with respect to cavity aspect ratio is found to be qualitatively consistent with results of 2D simulations. Secondary flow vortices whose axis is in the direction of the lid‐motion are observed; these are weak at low Reynolds numbers, but become quite strong at high Reynolds numbers.

The findings will be useful in the study of variety of enclosed fluid flows.

This paper describes the results for magnetic damping in torsional mode (TEAM problem 16). A total of six solutions are presented and compared with experimental results. The problem is treated as a coupled electromagnetomechanical one. In general numerical predictions agree well with experiment.

The digital down converter (DDC) is a principal component in modern communication systems. The DDC process traditionally entails quadrature down conversion, bandwidth reducing filters and commensurate sample rate reduction. To avoid group delay, distortion linear phase FIR filters are used in the DDC. The filter performance specifications related to deep stopband attenuation, small in-band ripple and narrow transition bandwidth lead to filters with a large number of coefficients. To reduce the computational workload of the filtering process, filtering is often performed as a two-stage process, the first stage being a down sampling Hoegenauer (or cascade-integrated comb) filter and a reduced sample rate FIR filter. An alternative option is an M-Path polyphase partition of a band cantered FIR filter. Even though IIR filters offer reduced workload to implement a specific filtering task, the authors avoid using them because of their poor group delay characteristics. This paper aims to propose the design of M-path, approximately linear phase IIR filters as an alternative option to the M-path FIR filter.

Two filter designs are presented in the paper. The first approach uses linear phase IIR low pass structure to reduce the filter’s coefficient. Whereas the second approach uses multipath polyphase structure to design approximately linear phase IIR filter in DDC.

The authors have compared the performance and workload of the proposed polyphase structured IIR filters with state-of-the-art filter design used in DDC. The proposed design is seen to satisfy tight design specification with a significant reduction in arithmetic operations and required power consumption.

The proposed design is an alternate solution to the M-path polyphase FIR filter offering very less number of coefficients in the filter design. Proposed DDC using polyphase structured IIR filter satisfies the requirement of linear phase with the least number of computation cost in comparison with other DDC structure.