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The purpose of this paper is to perform the limiting performance analysis of a vehicle restraint system (seat belt) in order to find the optimal control force, and its pre-acting time that minimizes the risk of injury.

A discrete model of the human thorax is used. A multiobjective optimum design problem is formulated in order to minimize the risk of injuries in case of impact. Several injury criteria are minimized and are required to remain below a safety threshold value.

The authors found which of the objectives are contradictory and which are not. Several of the optimal sets of design variables are analyzed and their performance compared to one another. The results are also compared to the case of not taking in account the pre-acting time. As expected, the results in this case are worse.

As with all limiting performance analysis, the technological implementation restraints of the control force are not taken into account. As such, the solutions must be considered a benchmark to which the actual solution can be compared to.

The limiting performance analysis concept allows us to have a theoretical benchmark to which the real control performance can be compared to.

As far as the authors know, the pre-acting time, and its implications on the improvement of the performance of the control system, is an original contribution to the problem the authors tried to solve.

To the purpose of this paper is to show the main features of the Direct Multisearch method and how it can be enhanced and hybridized without compromising its mathematical properties.

The study is based on a mathematical analysis of the properties of the method which is then validated with analytical benchmarks and tested on a problem related to magnetic-assisted surgery.

The presented multi-objective optimizer, based on an extension of the well-known Pattern Search (PS) method, due to its deterministic nature, enjoys provable convergence properties. Furthermore, the method is successfully extended by hybridizing it with some stochastic approaches in order to improve its performance. Numerical examples show the effectiveness of the developed approach which can be used as a general and robust tool for multi-objective optimization. In a specific application, related to magnetic-assisted surgery, the proposed algorithm achieved 100 percent detection accuracy under realistic test conditions.

Due to the provable convergence characteristics of the algorithm, the presented technique can be applied to problems where minima must be identified with very high accuracy.

The paper presents enhanced and hybridized versions of the PS algorithm.

Although the Internet is already a valuable information resource in medicine, there are important challenges to be faced before physicians and general users will have extensive access to this information. As a result of a research effort to compile a health‐related Internet directory, new tools and strategies have been developed to solve key problems derived from the explosive growth of medical information on the Net and the great concern over the quality of such critical information. The current Internet search engines lack some important capabilities. We suggest using second generation tools (client‐side based) able to deal with large quantities of data and to increase the usability of the records recovered. We tested the capabilities of these programs to solve health‐related information problems, recognising six groups according to the kind of topics addressed: Z39.50 clients, downloaders, multisearchers, tracing agents, indexers and mappers. The evaluation of the quality of health information available on the Internet could require a large amount of human effort. A possible solution may be to use quantitative indicators based on the hypertext visibility of the Web sites. The cybermetric measures are valid for quality evaluation if they are derived from indirect peer review by experts with Web pages citing the site. The hypertext links acting as citations need to be extracted from a controlled sample of quality super‐sites.