Tradeoff analysis of technology needs for public service helicopters

The design requirements for a family or type of Public Service Helicopter (PSH) is examined which will satisfy the needs of municipal and state governments in the following mission areas: Emergency Medical Service--Airborne Rescue Squad; Law Enforcement; Search and Rescue; and Environmental Control (Fire Fighting, Pollution, Resource Management). The report compares both design and performance requirements as specified by the PSH user's group against current technological capabilities, RTOPS and US Army LHX design requirements. The study explores various design trade-offs and options available to the aircraft designer/manufacturer in order to meet the several criteria specified by the PSH user's group. In addition, the report includes a brief assessment of the feasibility of employing certain advanced rotorcraft designs to meet the stringent combination of operational capabilities desired by the Public Service Helicopter Users

SIMULATION STUDY OF A STANDALONE PHOTOVOLTAIC ELECTRICITY GENERATION SYSTEM

The energy demand of the nation is growing rapidly as Malaysia thrusts forward towards becoming a developed nation. Generation of electricity is still heavily dependent on combustion of fossil fuels such as natural gas and coal. The emissions from the combustion of fossil fuels have led to serious environmental and climatic problems such as global warming and air pollution. The depleting nature of fossil fuels adds further constraint to the utilization of these fuels in meeting the nation’s future energy needs. The problems associated with fossil fuels initiated the interest to explore alternative energy sources that are more environmentally friendly and sustainable for electricity generation. Since Malaysia is located near the equator with monthly average daily solar irradiation of approximately 4500 Wh/m2 and average sunshine duration of up to 8 hours, the utilization of solar energy for electricity generation has great prospects. The photovoltaic-based electricity generation system (PVEGS) converts sunlight into electricity using photovoltaic (PV) modules. However, sunlight is not available continuously throughout the day. The transient nature of solar energy affects the performance of the PV module which results in the need for efficient control and storage of energy. PVEGS installation designing and sizing are crucial for optimum system operation but are complicated due to the characteristics of the energy resource and complexities of system component operation. A simulation program is developed to assist users with the designing and sizing of PVEGS installations according to the solar resource available at site for practical implementation. A PVEGS prototype is implemented in Ipoh using the design and sizing recommendations provided by the simulation program. The prototype is tested and was found to be operating up to expectation and according to the specified requirements. The simulated performance of the PVEGS has a reasonably good correlation of 84.1% with the performance of the implemented PVEGS prototype

A Review of Production Planning Models: Emerging features and limitations compared to practical implementation

In the last few decades, thanks to the interest of industry and academia, production planning (PP) models have shown significant growth. Several structured literature reviews highlighted the evolution of PP and guided the work of scholars providing in-depth reviews of optimization models. Building on these works, the contribution of this paper is an update and detailed analysis of PP optimization models. The present review allows to analyze the development of PP models by considering: i) problem type, ii) modeling approach, iii) development tools, iv) industry-specific solutions. Specifically, to this last point, a proposed industrial solution is compared to emerging features and limitations, which shows a practical evolution of such a system

Trombe walls with nanoporous aerogel insulation applied to UK housing refurbishments

There is an opportunity to improve the efficiency of passive Trombe walls and active solar air collectors by replacing their conventional glass covers with lightweight polycarbonate panels filled with nanoporous aerogel insulation. This study investigates the thermal performance, energy savings, and financial payback period of passive Aerogel Trombe walls applied to the existing UK housing stock. Using parametric modeling, a series of design guidance tables have been generated, providing estimates of the energy savings and overheating risk associated with applying areas of Trombe wall to four different house types across the UK built to six notional construction standards. Calculated energy savings range from 183 kWh/m2/year for an 8 m2 system retrofitted to a solid walled detached house to 62 kWh/m2/year for a 32 m2 system retrofitted to a super insulated flat. Predicted energy savings from Trombe walls up to 24 m2 are found to exceed the energy savings from external insulation across all house types and constructions. Small areas of Trombe wall can provide a useful energy contribution without creating a significant overheating risk. If larger areas are to be installed, then detailed calculations would be recommended to assess and mitigate potential overheating issues.The EPSRC, Brunel University, and Buro Happold Lt

Cost analysis of new and retrofit hot-air type solar assisted heating systems

A detailed cost analysis/cost improvement study was performed on two Department of Energy/National Aeronautics and Space Administration operational test sites to determine actual costs and potential cost improvements of new and retrofit hot air type, solar assisted heating and hot water systems for single family sized structures. This analysis concentrated on the first cost of a system which included procurement, installation, and integration of a solar assisted heating and hot water system on a new or retrofit basis; it also provided several cost projections which can be used as inputs to payback analyses, depending upon the degree of optimism or future improvements assumed. Cost definitions were developed for five categories of cost, and preliminary estimates were developed for each. The costing methodology, approach, and results together with several candidate low cost designs are described

Feasibility study of an Integrated Program for Aerospace vehicle Design (IPAD). Volume 1A: Summary

IPAD was defined as a total system oriented to the product design process. This total system was designed to recognize the product design process, individuals and their design process tasks, and the computer-based IPAD System to aid product design. Principal elements of the IPAD System include the host computer and its interactive system software, new executive and data management software, and an open-ended IPAD library of technical programs to match the intended product design process. The basic goal of the IPAD total system is to increase the productivity of the product design organization. Increases in individual productivity were feasible through automation and computer support of routine information handling. Such proven automation can directly decrease cost and flowtime in the product design process

Applications of high and low fidelity prototypes in researching intuitive interaction

This paper addresses some of the issues involved in incorporating use of prototypes into a research program. Definitions, merits and uses of both low and high-fidelity prototypes are discussed and then the applications of prototypes in our research program into intuitive interaction are explored. It has previously been established that intuitive interaction is based on past experience, and can be encouraged by designing interfaces that contain familiar features (Blackler, 2006; Blackler, Popovic, & Mahar, 2007b). Two aspects of the research program which are relevant to prototyping are: researching the issues of how intuitive use happens and how it can be better facilitated; and developing ways to help designers include investigations about users and their existing knowledge into their design processes in order to make interfaces more intuitive. The current and future planned applications of high and low-fidelity prototypes in each of these areas are explored. Then experiences with using high-fidelity touchscreen prototypes for experimental research into intuitive interaction are discussed, including problems with the prototypes, how they were addressed and what we have learned from the process. Next the potential for low-fidelity prototypes to elicit users’ tacit knowledge during the design process is explored. This has exciting possibilities due to the link between intuitive interaction and tacit knowledge. Finally, the challenges of developing prototype-based design tools for use by older people are discussed and future directions for using prototypes in our research program are considered. Keywords: Prototypes; intuitive interaction; experimental methodology; implicit or tacit knowledge</p

A conceptual design methodology for evaluation of alternate propulsion system modifications on small aircraft

Conceptual design is often considered to be the most important step in the design of a new product or the modification of an existing product. The important steps in this conceptual design phase is the synthesis of potential solutions into concepts, the evaluation of these concepts within a repeatable and robust design methodology framework and analysis to identify and characterise the preferred solution concept. This research has arisen from problems associated with developing aircraft-based design modification concepts and predicting the impact of these changes as they propagate or flow down through the various aircraft subsystems, impacting engineering design, and leading to certification and operations challenges. This research problem is particularly evident in highly integrated systems such as high-performance military aircraft, helicopters, and complex civil aircraft. To illustrate this methodology the author has selected two case studies which apply two different alternate propulsion system technologies to small aircraft. These case studies were selected to provide a diverse design modification space encompassing differing aircraft roles and mission types, differing technologies and subsystems integration scope, and different data sources collection and analysis methods. In order to combine the elements of design synthesis, evaluation of concept alternatives and analysis of outputs, this thesis has formulated a matrix-based conceptual design methodology. This methodology extends current knowledge by implementing the concepts of design synthesis, evaluation and analysis as an iterative process, and building and linking together existing techniques. This new methodology combined various techniques and methods such as Quality Function Deployment (QFD), quantified morphological matrices (QMM), Pugh’s decision matrices, change options Multiple-Domain Matrices (MDM), and has adapted the Change Propagation Method (CPM). The second extension to current knowledge in this area was the development of Engineering and Certification Domain Mapping Matrix (DMM) techniques based on Design Structure Matrices (DSM). This extension into engineering and certification domain was undertaken to ensure that important modification-related risks and costs were incorporated into the early stages of design. The extension adopted existing DSM and DMM-based techniques and tools to evaluate the impact of changes to subsystems and hence impact of risks and costs resulting from aircraft modifications using change propagation method analysis techniques. The validation of this conceptual design methodology was achieved by verifying and assessing the adequacy of its application through an analysis process which examined (1) coverage of the design space attributes; (2) validation of the methodology against accepted scientific and industry conceptual design frameworks; and (3) confirmation of the existing techniques, structures and tools applied within the methodology

High speed research system study. Advanced flight deck configuration effects

In mid-1991 NASA contracted with industry to study the high-speed civil transport (HSCT) flight deck challenges and assess the benefits, prior to initiating their High Speed Research Program (HSRP) Phase 2 efforts, then scheduled for FY-93. The results of this nine-month effort are presented, and a number of the most significant findings for the specified advanced concepts are highlighted: (1) a no nose-droop configuration; (2) a far forward cockpit location; and (3) advanced crew monitoring and control of complex systems. The results indicate that the no nose-droop configuration is critically dependent upon the design and development of a safe, reliable, and certifiable Synthetic Vision System (SVS). The droop-nose configuration would cause significant weight, performance, and cost penalties. The far forward cockpit location, with the conventional side-by-side seating provides little economic advantage; however, a configuration with a tandem seating arrangement provides a substantial increase in either additional payload (i.e., passengers) or potential downsizing of the vehicle with resulting increases in performance efficiencies and associated reductions in emissions. Without a droop nose, forward external visibility is negated and takeoff/landing guidance and control must rely on the use of the SVS. The technologies enabling such capabilities, which de facto provides for Category 3 all-weather operations on every flight independent of weather, represent a dramatic benefits multiplier in a 2005 global ATM network: both in terms of enhanced economic viability and environmental acceptability

Asteroid Redirect Crewed Mission Space Suit and EVA System Maturation

The Asteroid Redirect Crewed Mission (ARCM) requires a Launch/Entry/Abort (LEA) suit capability and short duration Extra Vehicular Activity (EVA) capability from the Orion spacecraft. For this mission, the pressure garment selected for both functions is the Modified Advanced Crew Escape Suit (MACES) with EVA enhancements and the life support option that was selected is the Exploration Portable Life Support System (PLSS) currently under development for Advanced Exploration Systems (AES). The proposed architecture meets the ARCM constraints, but much more work is required to determine the details of the suit upgrades, the integration with the PLSS, and the tools and equipment necessary to accomplish the mission. This work has continued over the last year to better define the operations and hardware maturation of these systems. EVA simulations were completed in the Neutral Buoyancy Lab (NBL) and interfacing options were prototyped and analyzed with testing planned for late 2014. This paper discusses the work done over the last year on the MACES enhancements, the use of tools while using the suit, and the integration of the PLSS with the MACES