Local multi-valued logics in modular expert systems

Abstract

Abstract. In this paper we describe an approach to the problem of dealing with uncertainty by means of finite multi-valued logics in modular expert systems, and the results obtained. The modularity of the systems allows us to address two main characteristics of human problem-solving: the adaptation of general knowledge to particular problems and the dependency of the management of uncertainty on the different subtasks being implemented in the modules of the system, i.e. different modules can have different local multiple-valued logics as part of their local deductive mechanisms. Although the results obtained are general, we use, throughout the paper, examples of a medical expert system that has been designed using a modular language called MILORD-II, that implements them showing the practical interest of the theoretical concepts involved.     

Application of iterative suboptimal strategies for improving adaptation transients in adaptive systems

Some solutions which involve iterative optimization techniques are given to improve adaptation transients in adaptive systems. Two suboptimal controllers are developed and applied to an equivalent discrete-time system valid for describing the behaviour of a recent adaptive control scheme when one of the (time-varying) parameters entering the adaptation algorithm varies within a closed domain admissible from a convergence point of view. The resulting suboptimal control strategies are translated into corrections of this parameter in order to recompute the adaptation algorithm over a finite horizon. Some numerical simulations illustrate the usefulness of the proposed scheme.     

Developments in Printing by Rotary Screen

Factors are summarised which led to the development of screen and copper–roller techniques as two complementary systems for textile printing, and problems are explained which delayed the commercial exploitation of the rotary screen. Features of the print–paste applicator and the screen construction are studied. Recent improvements in durability and versatility of screens are examined, and novel fields of application for the rotary screen, particularly in duplex printing, are reviewed.     

The human dead ringer/bright homolog, DRIL1: cDNA cloning, gene structure, and mapping to D19S886, a marker on 19p13.3 that is strictly linked to the Peutz-Jeghers syndrome

A 2-year trial was conducted to evaluate the cost-effectiveness of heliotherapy for psoriasis. The course and cost of psoriasis of 46 Finnish patients were first closely monitored for 1 year, then the patients received a 4-week supervised heliotherapy treatment in the Canary Islands, Spain, after which they continued to be followed for another year. Heliotherapy dramatically reduced the severity of psoriasis and also seemed to have favourable long-term effects on psoriasis. The mean direct cost of the 4-week heliotherapy for one patient was FIM12,289 (1 Pound = FIM7.0 in 1989). The cost of flights and half-board in Spain formed nearly 60% (FIM7033) of the total cost. In the year preceding heliotherapy, the mean direct annual cost of antipsoriasis therapy was FIM7335 and in the year after FIM5700, a reduction of 22% in annual costs; this change was not statistically significant because there were large variations in costs among patients. The costs of heliotherapy exceeded manyfold the mean monthly cost of conventional psoriasis therapy. There were no overall savings using heliotherapy in those patients suffering mainly from moderately severe psoriasis. Heliotherapy saved costs only in those patients with severe psoriasis that required expensive medication or ward treatment. Although heliotherapy cannot be regarded as an economical treatment for the average patients with psoriasis, it clears psoriasis effectively and is preferred by patients. Thus, heliotherapy constitutes an alternative for patients suffering severe psoriasis.     

The removal of arsenic from （ground）-water by adsorbent loaded in polymeric microspheres

Arsenic is a natural tasteless and odourless element,existing in the earth’s crust at average levels of between two and five thousands micrograms per liter (parts per million) . Arsenic is highly toxic to humans, who are exposed to it primarily from air,food and water. The occurrence of arsenic in groundwater is due to geological composition of soil. High concentrations of arsenic in water are the result of dissolution or desorption of ferric oxides and the oxidation of mineral arsenopyrites. Arsenic in drinking water has an important impact on the human health,especially in the less developed countries. Different methods exist to remove arsenic from aquatic media,and one of them is by adsorption. In this work,the adsorption of both As(III) and As(V) by means of novel microspheres has been investigated. In particular,TiO2 has been embedded into polymeric microspheres PES (PolyEtherSulphone) and PEEK-WC (PolyEtherEther-Ketone) . The main advantages of this encapsulation adsorption material are: no loss of adsorbents into the water stream,easy to be used and scaled-up.     

END-WINDING INFLUENCE ON HOMOPOLAR EFFECTS IN ASYMMETRICAL THREE-PHASE MACHINE WINDINGS

ABSTRACT

Asymmetries in three-phase windings of rotating-field a.c, machines may cause homopolar currents in delta-connected phase windings. End-winding particulars can have an Important quantitative influence on these currents and on the connected phase current inequalities.     

ROTOR RESISTANCE ESTIMATION FOR SLIP ADAPTATION IN SENSORLESS INDUCTION MACHINE DRIVES

ABSTRACT

This work presents a rotor resistance estimation algorithm. The estimation process is based on a recursive least squares method. It is applied to a speed sensorless induction motor drive scheme in order to implement slip adaptation. A discrete approach is considered in which an induction motor model written in form of difference equations is used by the estimation algorithm. All the associated mathematical developments are shown. Simulation results are used to verify the performance of the proposed rotor resistance estimator.     

纤维的结构和性能（Ⅲ）

本文介绍了ＰＥＴ高速纺丝纤维的热性能，低速纺丝领域中纤维的大分子取向以及纤维结晶相和非结晶相的取向，指出：纤维的沸水收缩率在纺速为２０００－３０００ｍ／ｍｉｎ内达最大值，其后随纺速增加急剧减少；纤维结晶相取向度随纺增加而增大；非晶向取向在６００ｍ／ｍｉｎ纺速以随纺速增加而增大，６０００ｍ／ｍｉｎ纺速以上随纺增加而减少。另外指出纺丝速度在７０００ｍ／ｍｉｎ以上时，ＰＥＴ纤维横断面上存在一个内部结构分