Measurements with multi-point microprobes: Effect of suspended solids on the hydrodynamics of bubble columns for application in chemical and biotechnological processes

Many experimental studies reveal that suspended solids considerably alter the coalescence behaviour and hydrodynamic functions of wo-phase flow. But no systematic efforts have yet been undertaken to separate the effects of different particle properties on local gas hold-up, bubble size and interfacial area gas/liquid. The aim of this paper is to present the local values of these parameters in three-phase fluidized beds of different solids, using miniaturized optical fiber and conductivity needle probes. It is shown that particle concentration, size and, in particular, density are decisive for the change in coalescence behaviour. Ranges of normal (?_S > ?_L) and inverse fluidization (?_S < ?_L) must be distinguished and the flow regime also exerts a strong influence on the interactions between the dispersed phases, the transition point itself being a function of particle properties can be observed, This effect is evaluated for different column diameters, between 0.1 and 0.3 m.     

Visualization of Back Pain Data—A 3-D Solution

Traditional approaches to gathering and visualizing pain data rely on two-dimensional (2-D) human body models, where different types of sensation are recorded with various monochrome symbols. We propose an alternative that uses a three-dimensional (3-D) representation of the human body, which can be marked in color to visualize and record pain data.     

Reflex-oscillations in evolved single leg neurocontrollers for walking machines

As a prerequisite for developing neural control for walking machines that are able to autonomously navigate through rough terrain, artificial structure evolution is used to generate various single leg controllers. The structure and dynamical properties of the evolved (recurrent) neural networks are then analysed to identify elementary mechanisms of sensor-driven walking behaviour. Based on the biological understanding that legged locomotion implies a highly decentralised and modular control, neuromodules for single, morphological distinct legs of a hexapod walking machine were developed by using a physical simulation. Each of the legs has three degrees of freedom (DOF). The presented results demonstrate how extremely small reflex-oscillators, which inherently rely on the sensorimotor loop and e.g. hysteresis effects, generate effective locomotion. Varying the fitness function by randomly changing the environmental conditions during evolution, neural control mechanisms are identified which allow for robust and adaptive locomotion. Relations to biological findings are discussed.     

Approach versus avoidance: Different types of commitment in intimate relationships.

The major objective of the present study was to examine whether approach versus avoidance commitment to one's intimate relationship was differentially predictive of relationship quality parameters in the long run. In the 1st testing period, 134 participants (67 romantic couples) answered questions about approach- versus avoidance-related measures. Commitment and relationship quality parameters such as satisfaction and emotions depending on the partner's presence were assessed in all 3 testing periods. The proposed distinction between an approach and an avoidance type of commitment was validated through correlations with other approach- versus avoidance-related measures. Longitudinal analyses revealed that approach commitment predicted relationship quality parameters positively, whereas avoidance commitment predicted them negatively. The results are discussed in terms of the benefit of an approach-avoidance-based conceptualization of commitment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Timed Concurrent Constraint Programming for Analysing Biological Systems

In this paper we present our first approach to model and verify biological systems using ntcc, a concurrent constraint process calculus. We argue that the partial information constructs in ntcc can provide a suitable language for such systems. We also illustrate how ntcc may provide a unified framework for the analysis of biological systems, as they can be described, simulated and verified using the elements provided by the calculus.     

Power plant investment in restructured markets

Investment opportunities in electric power generation have changed dramatically since electricity industry restructuring first began. In contrast to regulated utilities adding capacity in line with central planning and regulation, power plant investment is now more often made by independent companies who market power across multiple utility jurisdictions. Because the regulatory approval process is long and outcomes uncertain, developers often plan multiple options for a given development budget. As more information is revealed about the future prospects at different sites, options are abandoned sequentially until only projects that will be completed remain. In this paper we evaluate the decision to build new generation facilities in a changing and uncertain regulatory environment. We estimate hazard rates for new power plant projects using a database of generation projects in North America and examine in greater detail the development patterns in California and Texas, two states with very different regulatory regimes. We find that regulatory uncertainty significantly affects the pattern of development in the electric power generation industry.     

Euclidean push–pull partial covering problems

This paper considers a bicriteria model to locate a semi-obnoxious facility within a convex polygon. Assuming that a given number of closest points and farthest points may be neglected in the analysis, it considers simultaneously the resulting push and pull partial covering criteria with Euclidean distances. Although both objectives are neither concave or convex, low complexity polynomial algorithms to find all the efficient solutions and the tradeoffs involved are developed by way of higher-order Voronoi diagrams. Comparison of the tradeoff for full covering and partial covering enables decision makers to understand to what extent the maximin and minimax criteria are improved at the expense of neglecting some points. The extensions to different sets of points pulling and pushing the facility and to weighted points are discussed. All methods are illustrated via small scale examples.     

A new system for computer-aided preoperative planning and intraoperative navigation during corrective jaw surgery.

A new system for computer-aided corrective surgery of the jaws has been developed and introduced clinically. It combines three-dimensional (3-D) surgical planning with conventional dental occlusion planning. The developed software allows simulating the surgical correction on virtual 3-D models of the facial skeleton generated from computed tomography (CT) scans. Surgery planning and simulation include dynamic cephalometry, semi-automatic mirroring, interactive cutting of bone and segment repositioning. By coupling the software with a tracking system and with the help of a special registration procedure, we are able to acquire dental occlusion plans from plaster model mounts. Upon completion of the surgical plan, the setup is used to manufacture positioning splints for intraoperative guidance. The system provides further intraoperative assistance with the help of a display showing jaw positions and 3-D positioning guides updated in real time during the surgical procedure. The proposed approach offers the advantages of 3-D visualization and tracking technology without sacrificing long-proven cast-based techniques for dental occlusion evaluation. The system has been applied on one patient. Throughout this procedure, we have experienced improved assessment of pathology, increased precision, and augmented control.