Multi-discipline Problem Research Articles

A perturbation adaptive pursuit strategy based hyper-heuristic for multi-objective optimization problems

Abstract For multi-objective optimization problems, obtaining a uniformly distributed approximation set is among the most important issues. During the past decades, various diversity mechanisms have been proposed to address this challenge. However, the existing diversity mechanisms tend to be problem-specific, and may not generalize well over different problem domains. Inspired by the idea of utilizing multiple low-level heuristics to achieve better diversity performance in multi-discipline problem solving, we focus on efficient algorithm design based on the methodology of selection hyper-heuristics. This study proposes a novel selection hyper-heuristic operating over multiple diversity mechanisms. The unique feature of the proposed approach lies in its ability to intelligently learn, select, and combine different diversity mechanisms with the purpose of taking advantages of them to obtain well-distributed approximation sets. Moreover, this work develops a new learning mechanism, the perturbation adaptive pursuit strategy, which is incorporated into the proposed hyper-heuristic to improve the decision-making process of selecting suitable diversity mechanisms for the problem at hand. The performance of the proposed hyper-heuristic is tested on 2-objective ZDT, 3-objective DTLZ, and 5-objective WFG test suites. Additionally, experiments are also conducted to investigate the ability of the novel hyper-heuristic to integrate existing multi-objective meta-heuristics on MaOP test suite from 3- to 10-objectives. Experimental results demonstrate the effectiveness of the proposed selection hyper-heuristic for cross-domain capacity, particularly in producing well distributed approximation set with respect to Spacing metric and Hypervolume metric.

Vertigo in neurological practice: rare causes and difficult decisions

The dizziness is a multidiscipline problem in management of neurologists, ototrhinolaryngologists, general practicioners. The first clinical goal seems to be the differentiation between central and peripherial vestibular syndrome. After that doctor should search the nosological form. It may become the challenge if the disease is rare. In such cases it is impossible to limit the therapy with vestibular rehabilitation with usement of the vertigolitic drugs. Accordingly to nososlogical form surgical methods, anticonvulsants, glucocorticoids or cytostatics may be needful.

Secondary Encoding

Translation between media is often used to make information encoded in one modality available to users who are unable to make use of that modality. Translation acts on the primary means of encoding the information (e.g., text, sound). Secondary encoding (e.g., color, intonations) is often added to primarily encoded information to help the user correctly interpret its intended meaning. During translation between media, secondary encodings are often removed and their information remains inaccessible. When this happens, miscommunications may occur. Although secondary encoding is a multi-discipline problem, different types of secondary encoding are usually analyzed as separate problems. In reality, they are aspects of a single problem. This paper presents a taxonomy of secondary encodings and guidance for improving the accessibility of secondary encoded information.

Experiences with Automatic Differentiation Applied to a Volume Grid Generation Code

Automatic differentiation (AD) is a methodology for developing reliable sensitivity-enhanced versions of arbitrary computer programs with little human effort. As such, it can vastly accelerate the use of advanced simulation codes in a multidisciplinary design optimization context because the time for generating and verifying derivative codes is greatly reduced. The application of the recently developed automatic differentiation of C programs (ADIC) prototype tool for ANSI-C programs on the coordinate and sensitivity calculator for multidisciplinary design optimization multiblock three-dimensional volume grid generator are reported. The ADIC-generated code can easily be interfaced with Fortran derivative codes generated with the ADIFOR AD tool for Fortran 77 programs; thus providing efe cient sensitivityenhancement techniques for multilanguage, multidiscipline problems.

Communications aspects of intercontinental deployment of enterprise wide applications

Using telecommunication networks and shared databases, modern enterprises may deploy the applications that will hold the operations fabric of their enterprises together and improve their worldwide competitiveness. Enterprise-wide applications deployment is a complex systems integration project, even in cases of single-country deployment, because the computing platforms, databases, applications, and communications infrastructure have to be planned and deployed in concert with each other. When the regional and corporate headquarters are on different continents, network planners, data processing (DP) personnel, and executive management alike find themselves dealing with this multidiscipline problem complicated by multicontinental logistics. We consider a number of technical architecture options for the enterprise-wide applications deployment of intercontinental multisite operations and qualify them in terms of their feasibility, technical risks, capital and operation costs, and user satisfaction. We also address the spongy keyboard problem, a condition that may make centralized solutions unsuitable for intercontinental deployment. In choosing the technical architecture to support enterprise-wide applications, we consider the following options: centralized processing, autonomous processing with centralized batch consolidation, regionalized processing with ongoing centralized consolidation, and regionalized processing with global distributed consolidation.