A generic coordination approach applied to a manufacturing environment

This paper describes a generic coordination approach applied to the field of manufacturing engineering. The objective of the coordination mechanism with respect to this application is twofold. Firstly, it is shown that utilising the developed system can result in the efficient organisation of processes leading to a near optimum time taken to manufacture a number of artefacts. Secondly, successful operation of the system in this environment will demonstrate that the approach is generic in nature. The results already achieved using this system within a computational analysis environment supports this hypothesis

Measured electron contribution to Shuttle plasma environment: Abbreviated update

The differential energy spectra of electrons between 1 and 100 eV were measured by an electron spectrometer flown on an early shuttle. This energy range was scanned in 64 incremental steps with a resolution of 7%. The most striking feature that was observed throughout these spectra was a relatively flat distribution of the higher energy electrons out to 100 eV. This is in contrast to normal ambient spectra which consistently show a rapid decline in quantitative flux beyond 50 to 55 eV. The lower energy (1 to 2 eV) end of these spectra showed steep thermal trails comparable to normal ambient spectral structure. In general, daytime fluxes were significantly higher than those obtained during nighttime measurements. Quantitative flux excursions which may possibly be associated with thruster firing were frequently observed. Spectral structure suggestive of the N2 vibrational excitation energy loss mechanism was also seen in the data from some measurement periods. Examples of these spectra are shown and possible correlations are discussed

A methodology for design coordination in a distributed computing environment

At the conceptual stage of the design process it is increasingly common that analysis tools are involved in the evaluation of a large number of alternative designs. Designers use such analysis tools to assist with large scale concept evaluations and the prediction of good initial designs. Consequently there exists a need to coordinate these analysis tools to enable the early stage of design to be performed in a timely and efficient manner. This paper describes a generic methodology that allows the management and coordination of design analysis tools. A Computer Aided Design tool, namely the Design Coordination System (DCS), has been developed to assist the designer in performing computational analysis in a distributed computing environment. Within the DCS, a collection of design agents act as members of a multi-functional team operating in a cooperative and coordinated manner in order to satisfy the objective of efficiently performing the design analysis

Real-time co-ordinated resource management in a computational enviroment

Design co-ordination is an emerging engineering design management philosophy with its emphasis on timeliness and appropriateness. Furthermore, a key element of design coordination has been identified as resource management, the aim of which is to facilitate the optimised use of resources throughout a dynamic and changeable process. An approach to operational design co-ordination has been developed, which incorporates the appropriate techniques to ensure that the aim of co-ordinated resource management can be fulfilled. This approach has been realised within an agent-based software system, called the Design Coordination System (DCS), such that a computational design analysis can be managed in a coherent and co-ordinated manner. The DCS is applied to a computational analysis for turbine blade design provided by industry. The application of the DCS involves resources, i.e. workstations within a computer network, being utilised to perform the computational analysis involving the use of a suite of software tools to calculate stress and vibration characteristics of turbine blades. Furthermore, the application of the system shows that the utilisation of resources can be optimised throughout the computational design analysis despite the variable nature of the computer network

A methodology for prospective operational design co-ordination

Engineering companies are continually faced with the challenge of how best to utilise their design team given some design project. Decisions regarding how to distribute the project workload amongst the members of the design team are the responsibility of a project manager who, in order to do this, often relies upon previous experience and/or the support of some planning tool. Furthermore, a project manager rarely has the opportunity to assess the capability of the design team against the current work load in order to determine what, if any, alterations couldbe made to the team to facilitate appropriate reductions in project time and cost.This paper proposes a mathematical-based methodology aimed at identifying shortfalls in design teams, which if remedied would result in a more efficient project in terms of time and cost. The methodology provides a means of identifying those skills within the design team,with respect to the outstanding work load, in which improvements would have the greatest influence on reducing time and cost. In addition, the methodology employs a genetic algorithm for the purpose of scheduling tasks to be undertaken by potential design teams. The methodology is applied to two practical case studies provided by engineering industry.The first case study involves the assessment of a multi-disciplined design team consisting of single-skilled engineers. In contrast, the second case study entails the assessment of multiskilled engineers within a multi-disciplined design team. As a result of applying the methodology to the case studies, potential improvement to the design teams are identified and, subsequently, evaluated by observing their effects

Real-time co-ordinated scheduling using a genetic algorithm

Real-time co-ordination is an emerging approach to operational engineering management aimed at being more comprehensive and widely applicable than existing approaches. Schedule management is a key characteristic of operational co-ordination related to managing the planning and dynamic assignment of tasks to resources, and the enactment of the resulting schedules, throughout a changeable process. This paper presents the application of an agent-oriented system, called the Design Co-ordination System, to an industrial case study in order to demonstrate the appropriate use of a genetic algorithm for the purpose of real-time scheduling. The application demonstrates that real-time co-ordinated scheduling can provide significant reductions in time to complete the computational design process

Vitamin B12 measurements across neurodegenerative disorders.

Background:Vitamin B12 deficiency causes a number of neurological features including cognitive and psychiatric disturbances, gait instability, neuropathy, and autonomic dysfunction. Clinical recognition of B12 deficiency in neurodegenerative disorders is more challenging because it causes defects that overlap with expected disease progression. We sought to determine whether B12 levels at the time of diagnosis in patients with Parkinson's disease (PD) differed from those in patients with other neurodegenerative disorders. Methods:We performed a cross-sectional analysis of B12 levels obtained around the time of diagnosis in patients with PD, Multiple System Atrophy (MSA), Dementia with Lewy Bodies (DLB), Alzheimer's disease (AD), Progressive Supranuclear Palsy (PSP), Frontotemporal Dementia (FTD), or Mild Cognitive Impairment (MCI). We also evaluated the rate of B12 decline in PD, AD, and MCI. Results:In multivariable analysis adjusted for age, sex, and B12 supplementation, we found that B12 levels were significantly lower at time of diagnosis in patients with PD than in patients with PSP, FTD, and DLB. In PD, AD, and MCI, the rate of B12 decline ranged from - 17 to - 47 pg/ml/year, much greater than that reported for the elderly population. Conclusions:Further studies are needed to determine whether comorbid B12 deficiency affects progression of these disorders

1/n expansions for two-electron Coulomb matrix elements

The study of 1/n expansions for various atomic matrix elements, where n is the principal quantum number, plays an important role in the theoretical foundations of the quantum defect method. The paper develops an expansion in powers of 1/n 2 for hydrogenic boundstate wavefunctions which can be used to calculate 1/n expansions of matrix elements. The 1/n expansions of the two-electron direct and exchange Coulomb integrals are evaluated as an example. © 1993 IOP Publishing Ltd

A PC program to optimize system configuration for desired reliability at minimum cost

High reliability is desired in all engineered systems. One way to improve system reliability is to use redundant components. When redundant components are used, the problem becomes one of allocating them to achieve the best reliability without exceeding other design constraints such as cost, weight, or volume. Systems with few components can be optimized by simply examining every possible combination but the number of combinations for most systems is prohibitive. A computerized iteration of the process is possible but anything short of a super computer requires too much time to be practical. Many researchers have derived mathematical formulations for calculating the optimum configuration directly. However, most of the derivations are based on continuous functions whereas the real system is composed of discrete entities. Therefore, these techniques are approximations of the true optimum solution. This paper describes a computer program that will determine the optimum configuration of a system of multiple redundancy of both standard and optional components. The algorithm is a pair-wise comparative progression technique which can derive the true optimum by calculating only a small fraction of the total number of combinations. A designer can quickly analyze a system with this program on a personal computer

Acceleration of thermal ions at the lunar surface : Apollo XII observations

An experiment designed to measure the differential energy spectrum and a coarse mass spectrum of ions near the lunar surface (Suprathermal Ion Detector Experiment) was deployed by the Apollo XII astronauts. This experiment has yielded evidence for a general mechanism which accelerates originally thermal ions up to several hundred electron volts.by Hans Balsiger, John W. Freeman, Jr., and H. Kent Hills