The Value of Weapon System Reliability in a Combat Environment: Costs and Performance

1989 ◽  
pp. 387-406
Author(s):  
Karen W. Tyson ◽  
Stanley A. Horowitz ◽  
D. Graham McBryde ◽  
Peter Evanovich
Keyword(s):  
System Reliability ◽  
Weapon System ◽  
And Performance ◽  
Combat Environment

Loading and Design Parameter Uncertainty in the Dynamics and Performance of High-Speed-Parallel-Helical Stage of a Wind Turbine Gearbox

2013 ◽  
Author(s):  
Fisseha M. Alemayehu ◽  
Stephen Ekwaro-Osire
Keyword(s):  
Wind Turbine ◽  
Parameter Uncertainty ◽  
System Reliability ◽  
Design Parameter ◽  
High Speed ◽  
Probability Of Failure ◽  
Wind Turbine Gearbox ◽  
Input Shaft ◽  
Input Variables ◽  
And Performance

The Wind Turbine Gearboxes (WTGs) are highly subjected to variable torsional and non-torsional loads. In addition, the manufacturing and assembly process of these devices results in uncertainty in the system. These gearboxes are reported to fail in their early life of operation, within three to seven years as opposed to the expected twenty years of operation. Their downtime and maintenance process is the most costly of any failure of subassembly of wind turbines. The objective of this work is to perform a probabilistic multibody dynamic analysis (PMBDA) of the high-speed-parallel-helical stage of the gearbox of wind turbine that considers uncertainty of generator side torque loading and the input shaft speed, assembly errors and design parameter uncertainty. System reliability, probability of failure, and probabilistic sensitivities of all the input variables towards several performance functions have been measured and conclusions have been drawn. PMBDA has demonstrated a new dimension of design and installation of wind turbine gearboxes than traditional deterministic approach. In addition to revealing system reliability or under-performance through probability of failure, the method will also help designers to consider certain variables critically through the sensitivity results.

Mpt in the Air Force

1986 ◽  
Vol 30 (13) ◽  
pp. 1294-1295
Author(s):  
John Speigel ◽  
Mike Skinner
Keyword(s):  
Air Force ◽  
Weapon System ◽  
Integration System ◽  
Weapon Systems ◽  
System Acquisition ◽  
And Performance ◽  
And Training ◽  
Equal Consideration

The Air Force recognizes the importance of Manpower, Personnel, and Training (MPT) issues in weapon system acquisition. To give supportability of future weapon systems equal consideration to cost, schedule, and performance of the system, the Air Force has set out to build an integration system to monitor MPT issues.

scholarly journals Feedback on system or operator performance: Which is more useful for the timely detection of changes in reliability, trust calibration and appropriate automation usage?

2019 ◽  
Vol 63 (1) ◽  
pp. 312-316
Author(s):  
Yidu Lu ◽  
Nadine Sarter
Keyword(s):  
Performance Feedback ◽  
System Reliability ◽  
Target Identification ◽  
Identification Task ◽  
Operator Performance ◽  
Two Factors ◽  
Machine Systems ◽  
And Performance ◽  
Subjective Trust

Creating safe human-machine systems requires that operators can quickly notice changes in system reliability in the interest of trust calibration and proper automation usage. Operators’ readiness to trust a system is determined not only by the performance of the automation but also by their confidence in their own abilities. This study therefore compared the usefulness of feedback on the performance of either agent. The experiment required two groups of ten participants each to perform an automation-assisted target identification task with “Automation Performance Feedback” (APF) or “Operator Performance Feedback” (OPF). Four different scenarios differed with respect to the degree and duration of changes in system reliability. Findings indicate that APF was more effective for supporting timely adjustments of perceived system reliability, especially with large and long reliability changes. Subjective trust ratings and performance were not affected, however, suggesting that these two factors are closely linked and more relevant for automation reliance.

Development of TMSR-SF1 Protection System Prototype

2017 ◽  
Author(s):  
Jie Hou ◽  
Ye Liu ◽  
Bingying Li ◽  
Yongbo Wei ◽  
Guoqing Huang ◽  
...  
Keyword(s):  
Software Design ◽  
System Reliability ◽  
Performance Test ◽  
Energy System ◽  
Protection System ◽  
Third Party ◽  
And Performance ◽  
Modular Redundancy ◽  
Reactor Protection System ◽  
System Prototype

The reactor protection system (RPS) of TMSR-SF1, which is the first 10MW Solid Fuel experiment reactor for Thorium based Molten Salt Reactor (TMSR) Energy system, adopt FPGA as the key technology to develop the system based on the triple modular redundancy system architecture. The RPS prototype was developed follow the TMSR-SF1 conceptual design to demonstrate the function and performance and to test the system reliability. The system design of TMSR-SF1 RPS is introduced in detail in this paper, the emergency trip parameter is also discussed. The hardware & software design of the prototype including the kernel logical board card design, the chassis and cabinet design, the breaker cabinet design, etc. are described. The prototype passed the performance test and the third-party testing, results and discussion are reported.

A Numerical Study of Turbulence Generation and Induced Stresses in Pressure Reducing Orifice

2014 ◽  
Author(s):  
Mahmoud M. M. Gabr ◽  
Maher Y. A. Younan ◽  
Ahmed M. R. El-Baz
Keyword(s):  
Fluid Flow ◽  
Safety Factor ◽  
System Reliability ◽  
Pipe Wall ◽  
Numerical Study ◽  
Plate Thickness ◽  
The Other ◽  
Induced Stresses ◽  
And Performance ◽  
Turbulence Generation

In the present paper, a numerical fluid flow and induced stresses are studied for single hole and multi-hole orifice plates. Three multi hole configurations are studied; orifice with 3 holes, 5 holes and 7 holes. Turbulence characteristics behind each configuration are analyzed and orifice geometry strength and safety factor are assessed. The multi-hole orifice showed promising results in reducing the turbulence which would increase the system reliability and performance. On the other hand, multi-hole orifice showed weaker strength for same orifice plate thickness and higher probability for pipe wall erosion.

Tolerant System Reliability and Performance Evaluation with Imperfect Tests

2013 ◽  
Vol 333-335 ◽  
pp. 1782-1788
Author(s):  
Tao Zeng ◽  
Jie Chen ◽  
Tian Wei Zhang
Keyword(s):  
Performance Evaluation ◽  
System Reliability ◽  
Evaluation Method ◽  
Estimation Method ◽  
Engineering Application ◽  
Performance Degradation ◽  
Online Test ◽  
Performance Evaluation Method ◽  
Fault Mode ◽  
And Performance

The key system which requiring very high levels of reliability often use redundancy to enhance reliability index, e.g. tolerant system. During system operation, tolerant system monitors system state and reconfigures it to realize continuous working with system drawback. Considering the inevitable errors in system online test and the performance degradation, an estimation method for both system reliability and performance is proposed in this paper. Through analyzing the important fault mode in tolerant system, establishing the system reliability model based on k-out-n:G system description, and then considering the imperfect tests and corresponding performance degradation in these process, the reliability and performance evaluation method is given, moreover, the engineering operation flow of this method was established for it. An aircrafts rudder system is taken as an example for engineering application, which shows that this approach is feasible and effective.

scholarly journals Reducing the Visual Signature of the M4A1 Rifle

2016 ◽  
Vol 4 (2) ◽  
pp. 163-170
Author(s):  
Duke Choi ◽  
Kelvin Hockenbraugh-White ◽  
Jessica Mcallister ◽  
Christian Mckenrick ◽  
Paul Santamaria
Keyword(s):  
Decision Process ◽  
Change Process ◽  
Color Change ◽  
Short Wave ◽  
Weapon System ◽  
Small Arms ◽  
A Value ◽  
And Performance ◽  
Value Model ◽  
Black Color

The Maneuver Center of Excellence (MCoE) presented a directive to reduce the visual signature for small arms weapons by altering the color of the M4A1 rifle from its traditional black color. This research utilizes the Systems Decision Process (SDP) to develop and analyze alternatives to create a feasible and permanent solution to reduce the weapon’s visual signature. The research consisted of an extensive stakeholder and functional analysis to develop a value model and framework that provides a values-based recommendation. The model establishes an optimal color change process that accounts for the design and performance characteristics of the weapon system and the stakeholder’s values. The research also analyzes the potential integration of short wave infrared (SWIR) mitigation into the new color of the weapon. This analysis will establish a baseline methodology for weapon color change for all Army small arms weapons.

Dependent Competing Risks Modeling for Mechanical Systems Under Component and Performance Failure

2019 ◽  
Vol 5 (2) ◽  
Author(s):  
Jingyi Liu ◽  
Yugang Zhang ◽  
Bifeng Song
Keyword(s):  
Mechanical System ◽  
System Reliability ◽  
Failure Modes ◽  
Analysis Model ◽  
Component Failure ◽  
Proposed Model ◽  
Specific Performance ◽  
Dependent Competing Risks ◽  
And Performance

This paper establishes a competing failure analysis model for complex mechanical system under component failure and performance failure considering degradation. Traditionally, mechanical system is composed by a number of components. Meanwhile, mechanical system has the ability to accomplish its specific performance. Therefore, mechanism may fail because of two kinds of failure modes, the component failure due to degradation (such as component wear) and the performance failure (system couldn't complete performance). The two failure modes compete with each other because as soon as one mode occurs the system just fails. The component will degrade with time as system operates as well as the system performance. In this paper, Brownian motion (BM) with nonlinear drift is used to model the degradation of components based on which component failure is analyzed. The function of performance measurement is built by surrogate and performance failure is analyzed by it at different working circulation. Farlie–Gumbel–Morgenstern (FGM) copula is introduced to describe the dependence. The system reliability is analyzed by FGM copula as well as competing failure probability for each failure mode. Finally, a numerical example and an engineering case study are used to illustrate the proposed model.

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