Analyzing and Synthesizing Images by Evolving Curves with the Osher-Sethian Method

Numerical analysis of conservation laws plays an important role in the implementation of curve evolution equations. This paper reviews the relevant concepts in numerical analysis and the relation between curve evolution, Hamilton-Jacobi partial differential equations, and differential conservation laws. This close relation enables us to introduce finite difference approximations, based on the theory of conservation laws, into curve evolution. It is shown how curve evolution serves as a powerful tool for image analysis, and how these mathematical relations enable us to construct efficient and accurate numerical schemes. Some examples demonstrate the importance of the CFL condition as a necessary condition for the stability of the numerical schemes.     

n-octane dehydrocyclisation on monofunctional and bifunctional Pt/Al2O3 catalyst

The dehydrocyclisation of n-octane to iso-octane, ethylbenzene and o-, m- and p-xylene was investigated on monofunctional (non-acidic) and bifunctional (acidic) Pt/Al₂O₃ catalyst in a microcatalytic reactor with hydrogen as carrier at 1.8 atm and 563–673 K. On bifunctional Pt/Al₂O₃, the total conversion of n-octane started from a high value and decreased with increasing temperature for all pulse sizes investigated. The primary product of n-octane conversion on acidic Pt/Al₂O₃ was iso-octane. The product yield-temperature profiles showed a large initial production of iso-octane which decreased to a minimum as the catalyst temperature increased due to its conversion to ethylbenzene and o-xylene. On non-acidic Pt/Al₂O₃, the total conversion of n-octane increased initially and then went through a maximum as the catalyst temperature increased. The primary products of the reaction were found to be ethylbenzene and o-xylene, indicative of the activity of the metal to effect these ring closure reactions.     

International Mentoring

Abstract

Despite some obvious differences between the two countries, Australian experience and approaches are proving useful in technical assistance to current reforms in the Sri Lankan water sector. A system of bulk water allocation through transferable entitlements is proposed in a policy package being considered by government. Demand management measures, including sharing of water management costs, are also proposed. Integrated planning of basin water resources is expected to play an important part in the new water management strategy. Institutional recommendations have also been prepared. An apex National Water Resources Authority along with an inter-ministerial Water Resources Council and an appeal resolution Water Resources Tribunal are proposed to carry out planning, regulatory, co-ordination, and related functions. River basin committees are recommended for basin level coordination in many areas, while the Mahaweli Authority, a major irrigation-oriented development agency, is being restructured along the lines of a river basin authority with Australian and other national guidance. A long-term, bilateral relationship has also been proposed as a means of capacity building and technical support for emerging issues.     

Modelling the Competitive Growth of Primary,Allotriomorphic, and Secondary Alpha in Ti-6Al-4V

Metallurgical and Materials Transactions A - The competitive formation of allotriomorphic α along the prior β grain boundaries, secondary α-phase and the growth of globular primary...     

Analysis of Subcycle Electro-Optic Sampling Without Background

Journal of Infrared, Millimeter, and Terahertz Waves - We explore background-free options to detect mid-infrared (MIR) electric transients. The MIR field and a near-infrared probe interact via sum-...     

Drought Forecasting using Markov Chain Model and Artificial Neural Networks

Water resources management is a complex task. It requires accurate prediction of inflow to reservoirs for the optimal management of surface resources, especially in arid and semi-arid regions. It is in particular complicated by droughts. Markov chain models have provided valuable information on drought or moisture conditions. A complementary method, however, is required that can both evaluate the accuracy of the Markov chain models for predicted drought conditions, and forecast the values for ensuing months. To that end, this study draws on Artificial Neural Networks (ANNs) as a data-driven model. The employed ANNs were trained and tested by means of a statistically-based input selection procedure to accurately predict reservoir inflow and consequently drought conditions. Thirty three years’ data of inflow volume on a monthly time resolution were selected to enable calculation of the standardized streamflow index (SSI) for the Markov chain model. Availability of hydro-climatic data from the Doroodzan reservoir in the Fars province, Iran, allowed us to develop a reservoir specific ANN model. Results demonstrated that both models accurately predicted drought conditions, by employing a randomization procedure that facilitated the selection of the required data for the ANN to forecast reservoir inflow close to the observed values over a validation period. The results confirmed that combining the two models improved short-term prediction reliability. This was in contrast to single model applications that resulted into substantial uncertainty. This research emphasized the importance of the correct selection of data or data mining, prior to entering a specific modeling routine.     

Advance Care Planning in der Psychiatrie

Definition of the problem

The term Advance Care Planning describes a concept of comprehensive planning for future health care situations that, amongst others, aims at supporting people to set up advance statements defining goals and desired directions of patient care, using qualified, prospective counseling offers. Another aim is to promote the dissemination and implementation of this concept with the help of structural, mostly regional measures.

Arguments

This article discusses Advance Care Planning in psychiatry. It visualizes different forms of psychiatric advance statements and reports legal regulations from the US, Great Britain and Germany. Furthermore, this article provides an overview of international studies on the implementation of Advance Care Planning in psychiatry. These studies impressively illustrate the need of qualified counseling- and supportive offers, as without such offers, advance statements are hardly implemented and noticed in practice.

Conclusion

Against this background, the authors recommend the experimental implementation of (regional) Advance Care Planning programs as pilot projects, aiming at ameliorating quality and acceptance of advance statements in psychiatry. These projects should be scientifically accompanied, evaluated and where necessary adjusted.

     

NON-UNIFORM PARTICLE DISTRIBUTIONS DURING TUBE FLOWS OF NEUTRALLY BUOYANT SUSPENSIONS IN SECOND-ORDER FLUIDS

Flow through an inclined tube of a suspension of uniform, neutrally buoyant spheres in a second-order fluid has been analyzed using the theory of (Li and Slattery, 1989) The result predicts that the spheres will migrate toward the center of the tube, forming a core with a maximum packing density. The velocity and concentration distributions agree qualitatively with previous observations. The predicted apparent viscosity is significantly lower than that obtained with a cone-plate viscometer (limiting case in which the angle between the cone and the plate approaches zero) or a parallel-plate viscometer, in which uniform concentration distributions are expected.