Sensor Selection and Optimization for Health Assessment of Aerospace Systems

Aerospace systems are developed similarly to other large-scale systems through a series of reviews, where designs are modified as system requirements are refined. For space-based systems few are built and placed into service. These research vehicles have limited historical experience to draw from and formidable reliability and safety requirements, due to the remote and severe environment of space. Aeronautical systems have similar reliability and safety requirements, and while these systems may have historical information to access, commercial and military systems require longevity under a range of operational conditions and applied loads. Historically, the design of aerospace systems, particularly the selection of sensors, is based on the requirements for control and performance rather than on health assessment needs. Furthermore, the safety and reliability requirements are met through sensor suite augmentation in an ad hoc, heuristic manner, rather than any systematic approach. A review of the current sensor selection practice within and outside of the aerospace community was conducted and a sensor selection architecture is proposed that will provide a justifiable, dependable sensor suite to address system health assessment requirements

Pain Control in the African Context: the Ugandan introduction of affordable morphine to relieve suffering at the end of life

Dr Anne Merriman is the founder of Hospice Africa and Hospice Africa Uganda. She is presently Director of Policy and International Programmes. Here she tells the story of how HAU was founded. Dr Richard Harding is an academic researcher working on palliative care in Sub-Saharan Africa. This paper described Dr Merriman's experience in pioneering palliative care provision. In particular it examines the steps to achieving wider availability of opioids for pain management for those with far advanced disease. Hospice Africa Uganda has been a model facility in achieving high quality clinical care embedded in a strategy of advocacy and education, using a multifaceted approach that has addressed logistical, policy and legislative barriers. Until 1990 control of severe pain in Sub-Saharan Africa was non-existent except in Zimbabwe and S Africa. Oral affordable morphine was brought to Kenya through Nairobi Hospice that year, and to Uganda through Hospice Africa Uganda in 1993. This paper offers an example of a highly effective and cost efficient model of care that has transformed the ability to humanely manage the problems of those with terminal illness, and to offer a culturally appropriate "good death". Thus it is now possible to complete the ethical circle of care in resource poor circumstances

MILP approach for then design of vertical vapor-liquid separation vessels-comparison with heuristics

In this article we compare results from different heuristics approaches for the design of VLE separation vessels. In addition, we present an MILP approach that embeds the aforementioned heuristics and considers the discrete nature of the geometric variables. We show that different heuristics render different results and, while results from heuristics and MILP often coincide, significant departures occur.Fil: Fischer, Carlos Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; ArgentinaFil: Costa, André Hemerly L.. Universidade do Estado de Rio do Janeiro; BrasilFil: Bagajewicz, Miguel J.. Oklahoma State University; Estados Unido

Comparison of steady state and integral dynamic data reconciliation

Abstract This paper is devoted to the comparison of the performance of integral approach to dynamic data reconciliation and steady state data reconciliation. It is shown that in the absence of biases and leaks, the performance of both approaches is similar. Moreover, it is proven that once the appropriate variance is chosen, both methods are identical in the absence of accumulation terms. Finally, an analysis is made on how large the discrepancies are when there are accumulation terms

Design of non-isothermal Process Water Networks

Abstract Despite the fact that many methods have been developed for the optimization of process water networks, solving the problem simultaneously considering heat recovery has rarely been addressed. This paper presents a new approach for the simultaneous synthesis and optimization of heat integrated water networks. The procedure is based on mixed integer non-linear mathematical programming (MINLP). A new superstructure for heat exchanger network (HEN) synthesis capable of exploiting unique features of water networks, like non-isothermal mixing of different streams, thus providing potentially more cost-effective solutions, is proposed. An example is presented to illustrate the synthesis of heat integrated water networks using the proposed approach

A Multi-Objective Optimization Method to integrate Heat Pumps in Industrial Processes

Aim of process integration methods is to increase the efficiency of industrial processes by using pinch analysis combined with process design methods. In this context, appropriate integrated utilities offer promising opportunities to reduce energy consumption, operating costs and pollutants emissions. Energy integration methods are able to integrate any type of predefined utility, but so far there is no systematic approach to generate potential utilities models based on their technology limits. This work focusses on the integration of industrial heat pumps and the development of a corresponding heat pump data base. This latter offers the possibility to integrate different heat pump types to any process, in a flexible and systematic way. A methodology, integrating the heat pump data base in an energy integration problem, and using multi objective optimization in order to identify optimal solutions, is presented. The results of a brewery process are presented and analyzed

A self-validating control system based approach to plant fault detection and diagnosis

An approach is proposed in which fault detection and diagnosis (FDD) tasks are distributed to separate FDD modules associated with each control system located throughout a plant. Intended specifically for those control systems that inherently eliminate steady state error, it is modular, steady state based, requires very little process specific information and therefore should be attractive to control systems implementers who seek economies of scale. The approach is applicable to virtually all types of process plant, whether they are open loop stable or not, have a type or class number of zero or not and so on. Based on qualitative reasoning, the approach is founded on the application of control systems theory to single and cascade control systems with integral action. This results in the derivation of cause-effect knowledge and fault isolation procedures that take into account factors like interactions between control systems, and the availability of non-control-loop-based sensors