Dementia: a serious and enduring mental illness

At the 1997 RCN Congress, the RCN Mental Health and Older People Forum put forward a matter for debate--how the definition of 'serious and enduring mental illness' affects services to people with dementia. Subsequently, the RCN agreed both a position paper, which includes dementia in the definition, and an action plan for dissemination and support of the RCN position. Alison Soliman describes the background to the position paper.     

New family of active RC variable equalisers

A new family of active variable equalisers is introduced. The proposed variable equaliser transfer function is generated from Bode's classical transfer function using a new mathematical transformation. The new circuit uses a single operational amplifier and the required full range of variation is obtained by varying a single resistor Rv from zero to Ro (a reference resistance). The variable equaliser circuit requires a single shaping grounded impedance for realisation.     

Minimum sensitivity pole placer

A method is presented for designing a constant-gain state feedback controller for assigning the closed-loop poles of a linear time-invariant multivariable system to desired locations which at the same time minimizes the sensitivity of these poles to variation in the parameters of the plant. The design procedure is illustrated by examples.     

Optimal scalar Lyapunov functions for decentralised stabilisation of interconnected systems

The problem of stabilisation of interconnected linear systems is considered by means of scalar Lyapunov functions and aggregation. A sufficient condition is given for an interconnected system to be stabilised using only local state feedback. The aim is to provide the least restrictive condition possible, which is termed `optimal?, by properly choosing the state-variable weighting matrices for each subsystem.     

The effect of spherical projectile speed in ricochet off water and sand

Experimental results are reported for the ricochet of steel and duralumin spheres ( and 1 in. dia.), from shallow depths of water and dry sand. The critical angle for ricochet off water is shown to increase with speed to approach the theoretical limit of . For ricochet off sand the critical angle decreases with speed but a cut-off angle exists, , for which no ricochet occurs at any speed.     

On the Application of Functional Analysis to the Optimization of the Production of Hydroelectric Power

This paper presents a new approach the authors have used for solving the optimal long-term problem of a hydro power system for maximum expected benefits (benefits from energy generated by a hydro power system over the planning period plus the expected future returns from water left in storage at the end of that period). The problem is formulated as a minimum norm problem in the framework of functional analytic optimization technique. The proposed method takes into account the stochasticity of the water inflows, we assume that their probability properties are pre-estimated from past history. Numerical results are presented for a real system in operation consisting of three rivers; each river has two series reservoirs. The computing time using this approach is very small compared to that of other approaches.     

The oxygen,oxygen/sulphur dioxide and oxygen/carbon dioxide electrodes in molten lithium sulphate—potassium sulphate eutectic

Open-ciruit potential, potentiostatic and voltammetric measurements of the O₂, O₂/SO₂ and O₂/CO₂ electrodes have been made in molten Li₂SO₄K₂SO₄ eutectic at 625°C. In the absence of SO₂ the overall reaction of the O₂ electrode is the reduction of O₂ to O^2? through the formation of O^2?₂ ions. In the presence of SO₂ the overall reaction is the reduction of SO₂ and O₂ to SO^2?₄, probably through the formation of SO^2?₃. The overall reaction of the O₂/CO₂ electrode is similar to that of the same electrode in molten carbonates, ie the reduction of CO₂ and O₂ to CO^2?₃. The transfer coefficients and exchange currents have been estimated for these reactions on platinum and gold.     

Low Voltage Digitally Controlled CMOS Current Conveyor

In this paper, a digitally controlled current conveyo(DCCC) is presented. The proposed DCCC is based on rail-to-rail folded cascode implementation with a current division network (CDN). The CDN is used to provide control on the current gain of the DCCC. The CDN uses a novel current division technique based on differential pairs. The proposed DCCC can operate from ±1.5 V supply voltages. Applications of the proposed DCCC such as variable gain amplifiers (VGA) and digitally tunedfilters have been investigated. PSpice simulations based on the AMI 1.2 µm N-well level 3 parameters are in agreement with the presented work.