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In this paper, reproduced by permission of the Institute of Printed Circuits (USA), the pros and cons of die perforated and drilled holes are discussed in relation to speed of production and quality of plated‐through holes, both with etched and additive printed wiring boards, single‐ and double‐sided.

LeaRonal (UK) plc of Buxton, Derbyshire, specialists in plating and allied services to the printed circuit board industry, has appointed John Flynn to their technical staff. Mr Flynn, who will be based in his native Scotland, brings with him a decade of experience in electroless copper, hard gold plating and photoimageable processing in the PCB industry.

The Palexpo Exhibition and Conference Centre close to Geneva Airport was the location for this timely event organised by the EIPC and sponsored by Du Pont Electronics. Participants, including speakers, chairpersons and press, totalled approximately 190—perhaps a slightly lower figure than anticipated for this first European symposium on an issue of considerable significance for the industry.

The CCA is a non‐profit organisation composed of member companies within the state of California, aimed at providing an environment for information exchange between individuals involved in the printed circuit industry. Each branch holds monthly meetings on state‐of‐the‐art technology. Other benefits of CCA membership include: free admission to Nepcon technical sessions; educational and employment information; reduced fees for the annual fall symposium; and a monthly newsletter.

The subject of the meeting on 20 June was ‘Numerically Controlled Routing’. Dave Dosier, of Paul Dosier Associates, explained how important it is to maximise programming and routing equipment. Former dusty, noisy fabrication rooms are now humming with NC equipment.

ISHM (UK) presented a technical meeting on this topic on the 23rd October 1982 at the Cunard International Hotel, London. The meeting was attended by some 50 engineers, both those involved in the field of hybrids and potential users. It was generally felt that this was a useful meeting but more especially that it would have appealed to many potential users of hybrids, had the right people been able to be contacted.

Following the Supreme Court’s 1988 decision in Basic, securities class plaintiffs can invoke the “rebuttable presumption of reliance on public, material misrepresentations regarding securities traded in an efficient market” [the “fraud-on-the-market” doctrine] to prove classwide reliance. Although this requires plaintiffs to prove that the security traded in an informationally efficient market throughout the class period, Basic did not identify what constituted adequate proof of efficiency for reliance purposes.

Market efficiency cannot be presumed without proof because even large publicly traded stocks do not always trade in efficient markets, as documented in the economic literature that has grown significantly since Basic. For instance, during the recent global financial crisis, lack of liquidity limited arbitrage (the mechanism that renders markets efficient) and led to significant price distortions in many asset markets. Yet, lower courts following Basic have frequently granted class certification based on a mechanical review of some factors that are considered intuitive “proxies” of market efficiency (albeit incorrectly, according to recent studies and our own analysis). Such factors have little probative value and their review does not constitute the rigorous analysis demanded by the Supreme Court.

Instead, to invoke fraud-on-the-market, plaintiffs must first establish that the security traded in a weak-form efficient market (absent which a security cannot, as a logical matter, trade in a “semi-strong form” efficient market, the standard required for reliance purposes) using well-accepted tests. Only then do event study results, which are commonly used to demonstrate “cause and effect” (i.e., prove that the security’s price reacted quickly to news – a hallmark of a semi-strong form efficient market), have any merit. Even then, to claim classwide reliance, plaintiffs must prove such cause-and-effect relationship throughout the class period, not simply on selected disclosure dates identified in the complaint as plaintiffs often do.

These issues have policy implications because, once a class is certified, defendants frequently settle to avoid the magnified costs and risks associated with a trial, and the merits of the case (including the proper application of legal presumptions) are rarely examined at a trial.

In the last few years, the understanding of environmental problems has grown. Car producers – original equipment manufacturers – are aiming to reduce fuel consumption and pollution. In order to fulfil these aims, new technologies have been launched. Many hydraulics systems have been removed and replaced with electric ones, e.g. power steering, water and oil pump, etc. In this paper, an electromechanical subsystem used in an automotive application is analyzed. The subsystem is composed of interior permanent synchronous magnet motor and electronic control unit. The range of mechanical output power for studied system is up to 1 kW. The aim of this paper is to compare electromechanical systems working with different on‐board voltage levels in order to find the optimum balance between motors' and electronics' efficiency. This will help to decrease the total system's weight, the consequence of which will decrease fuel consumption and reduce CO₂ emissions.

During the analysis, the reduced order modelling (ROM) techniques has been applied. First, with utilization of finite‐elemente‐methode the basic motor's parameter like: synchronous inductance and flux per pole as a function of the direct‐axis current and also the quadrature‐axis current are calculated. In the second step, these parameters are used in the system simulation. During this simulation, the maximum torque per ampere control strategy together with ROM techniques was used.

As a result, the performance of the system for different voltage levels has been obtained. Additionally, the important factors for an electromechanical system, such as maximum power density, sizing and cost of the total electromechanical system, have been compared.

The performed comparison shows that the cost optimized system should work with the higher voltage, where the electric motor size is reduced ca. 25 per cent. This result is also valid for different electromechanical systems in an automotive area, e.g. automated manual transmission, engine cooling and electric compressor.

It is the first paper, where electric power steering system design for different on‐board voltage levels has been systematically analyzed and compared. Results from this paper can be also applied to different electromechanical systems mounted in hybrid or electric cars.