Showing papers on "Technical performance measure published in 2011"

Environmentally Responsible Aviation (ERA) Project - N+2 Advanced Vehicle Concepts Study and Conceptual Design of Subscale Test Vehicle (STV) Final Report

Abstract: NASA has set demanding goals for technology developments to meet national needs to improve fuel efficiency concurrent with improving the environment to enable air transportation growth. A figure shows NASA's subsonic transport system metrics. The results of Boeing ERA N+2 Advanced Vehicle Concept Study show that the Blended Wing Body (BWB) vehicle, with ultra high bypass propulsion systems have the potential to meet the combined NASA ERA N+2 goals. This study had 3 main activities. 1) The development of an advanced vehicle concepts that can meet the NASA system level metrics. 2) Identification of key enabling technologies and the development of technology roadmaps and maturation plans. 3) The development of a subscale test vehicle that can demonstrate and mature the key enabling technologies needed to meet the NASA system level metrics. Technology maturation plans are presented and include key performance parameters and technical performance measures. The plans describe the risks that will be reduced with technology development and the expected progression of technical maturity.

The Canonical Decomposition Fuzzy Comparative Methodology for Assessing Architectures

Abstract: The challenge for system architects is to perform a realistic assessment of an inherently ambiguous system concept. Many existing assessment methods are available, but these are often subjective and unrepeatable. Repeatability, objectivity, and increased fidelity are desired. An architecture assessment methodology capable of achieving these objectives is possible by drawing on the strengths of existing approaches while addressing their collective weaknesses. The proposed methodology is the Canonical Decomposition Fuzzy Comparative approach. The theoretical foundations of this methodology are developed herein and tested through the assessment of three physical architectures for a peer-to-peer wireless network. An extensible modeling framework is established to decompose high-level system attributes into technical performance measures suitable for analysis via computational modeling. Canonical design primitives are used to assess antenna performance in the form of a comparative analysis between the baseline free space gain patterns and the installed gain patterns. Finally, a fuzzy inference system is used to interpret the comparative feature set and offer a numerical assessment. The results of this experiment support the assertion that the proposed methodology is well suited for exposing integration sensitivity and assessing coupled performance in physical architecture concepts.

A Statistical Approach to the Development of Progress Plans Utilizing Bayesian Methods and Expert Judgment

Abstract: : The development of progress plans for each identified technical performance parameter (TPP) is a critical element of technical performance measurement. The measured values of TPPs are referred to as technical performance measures (TPMs). These terms are used interchangeably; however, TPMs more directly reflect how technical progress and technical risk are measured and evaluated. Progress plans, or planned performance profiles, are crucial to effective risk assessment; however, methods for developing these plans are subjective in nature, have no statistical basis or criteria as a rule, and are not sufficiently addressed in literature. The methodology proposed herein for progress plan development will involve the elicitation of expert judgments to formulate probability distributions that reflect the expected values/estimates used to establish progress plans.

Using Technical Performance Measures

Abstract: All programs have requirements. For these requirements to be met, there must be a means of measurement. A Technical Performance Measure (TPM) is defined to produce a measured quantity that can be compared to the requirement. In practice, the TPM is often expressed as a maximum or minimum and a goal. Example TPMs for a rocket program are: vacuum or sea level specific impulse (lsp), weight, reliability (often expressed as a failure rate), schedule, operability (turn-around time), design and development cost, production cost, and operating cost. Program status is evaluated by comparing the TPMs against specified values of the requirements. During the program many design decisions are made and most of them affect some or all of the TPMs. Often, the same design decision changes some TPMs favorably while affecting other TPMs unfavorably. The problem then becomes how to compare the effects of a design decision on different TPMs. How much failure rate is one second of specific impulse worth? How many days of schedule is one pound of weight worth? In other words, how to compare dissimilar quantities in order to trade and manage the TPMs to meet all requirements. One method that has been used successfully and has a mathematical basis is Utility Analysis. Utility Analysis enables quantitative comparison among dissimilar attributes. It uses a mathematical model that maps decision maker preferences over the tradeable range of each attribute. It is capable of modeling both independent and dependent attributes. Utility Analysis is well supported in the literature on Decision Theory. It has been used at Pratt & Whitney Rocketdyne for internal programs and for contracted work such as the J-2X rocket engine program. This paper describes the construction of TPMs and describes Utility Analysis. It then discusses the use of TPMs in design trades and to manage margin during a program using Utility Analysis.

Assessing system architectures: The canonical decomposition fuzzy comparative methodology

Abstract: : The impacts of decisions made during the selection of the system architecture propagate throughout the entire system lifecycle. The challenge for system architects is to perform a realistic assessment of an inherently ambiguous system concept. Subject matter expert interpretations, intuition, and heuristics are performed quickly and guide system development in the right overall direction, but these methods are subjective and unrepeatable. Traditional analytical assessments dismiss complexity in a system by assuming severability between system components and are intolerant of ambiguity. To be defensible, a suitable methodology must be repeatable, analytically rigorous, and yet tolerant of ambiguity. The hypothesis for this research is that an architecture assessment methodology capable of achieving these objectives is possible by drawing on the strengths of existing approaches while addressing their collective weaknesses. The proposed methodology is the Canonical Decomposition Fuzzy Comparative approach. The theoretical foundations of this methodology are developed and tested through the assessment of three physical architectures for a peer-to-peer wireless network. An extensible modeling framework is established to decompose high-level system attributes into technical performance measures suitable for analysis via computational modeling. Canonical design primitives are used to assess antenna performance in the form of a comparative analysis between the baseline free space gain patterns and the installed gain patterns. Finally, a fuzzy inference system is used to interpret the comparative feature set and offer a numerical assessment. The results of this experiment support the hypothesis that the proposed methodology is well suited for exposing integration sensitivity and assessing coupled performance in physical architecture concepts.

Technology Performance Risk Measure Method for System and Its Application

Abstract: Aiming at the problem that Technical Performance Measure(TPM) only accounts for the achieved performance instead of both the achieved and unmet performance,it is impossible to reflect the aggregated risk.This paper extends the technology category in TPM.A new kind of technology is added to the traditional TPM and the calculating formula is given.The proposed TPM is based on two concepts: the unmet performance and the degree of difficulty with the unmet performance.In order to demonstrate how to use this method,two applications are given.

Discussion on Military Technical Human Resources Value and Its Measurement

Abstract: Military technical human resource value points out the value of human resources which are devoted to military department for military intentionThis paper points out that it has several characters,such as complexity to measure,increment of valiance,compensatory lag and so on,and puts forward a way to measure military technical human resources value,which combines output and cost,lifecycle and earning cycle,currency measurement and non-currency measurement

The Development of a Model of Technical Expertise: Towards Innovative Teaching Methods in Technical Education

Abstract: Technical education plays a significant role in providing middle level manpower needed for work in various industries for development and economic growth of every nation. There is the need for technical education to provide students with expertise to cope with the changing industrial demands in the present knowledge and technological economy. However, research has identified a significant gap between technical education and industries. For this reason the present teaching methods and the practices of technical education have been questioned. This article discusses and analyses the cognitive processes of novice and expert technicians in line with expertise development from the perspective of cognitive psychology. The intention is to describe and propose a model of technical expertise towards the identification of innovative teaching methods for the development of technical expertise in technical schools.

Proposed Methodology for Performance Prediction and Monitoring for an Acknowledged Systems of Systems

Abstract: : Program managers (PMs) are expected to quantifiably justify that their program will result in the delivery of a system with the required performance through development. Traditionally, the PM has several technical management tools at their disposal, including Technical Performance Measures (TPMs), modeling and simulation, etc., that provide insight and predictive capability in system performance. When the program matures to a point where actual test data can be gathered, it is compared against expected system performance. The increasing use of the system of systems (SoS) model for the rapid fielding of warfighting capabilities poses new systems engineering challenges for the DoD. Due to the complex nature of SoS interdependencies, PMs are especially challenged when asked to quantifiably predict progress made toward full-capability SoS performance in an incremental development. To support the PM in making technical trades and tracking performance progress for an acknowledged SoS, the U.S. Navy (PMS 420 and SSC Pacific) have been collaborating on the development and verification of an SoS Performance Measure (SPM) tool set. The SPM tool applies a modified TPM-type approach to an SoS construct. However, instead of focusing on a single measurable technical value that can be monitored during development of an individual system the SPM links the SoS Key Performance Parameters (KPPs) to individual component capabilities, their maturity, and their potential usage rates. The System Maturity Model (SMM), Concept of Operations (CONOPS), and usage rate variance analyses are all considered in the SPM calculation. The SPM tool will be reviewed and valuable lessons learned to date within the Mission Modules Program will be discussed.