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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

The Aerospace Environmental Hazards: Diagnosis and Proposals for International Remedies

Valero Briceno, Hidalgo A. January 1981 (has links)

Fostering Continuous Improvement in a Changing Business Context. Textron Systems, Wilmington, Massachusetts, 1998,1999,2000

Cutcher-Gershenfeld, Joel January 2001 (has links)
This is a large non-union facility implementing systems change initiatives in a rapidly changing business context. Textron has been an important contributor to the U.S. defense aerospace business for five decades. Textron is a prime contractor with the U.S. government and supplier for other technologies. Textron sees workplace change initiatives as key to business success. It seeks performance gains through employee training and development. Textron Systems illustrates the ever-changing challenge of aligning employment systems with business strategy in the aerospace industry. It can sustain major change initiatives and is vulnerable to the swings that come with each new business contract. A combination of training, organizational development and work restructuring activities are being implemented. Even so, they cannot fully mitigate the instability associated with the defense aerospace sector.

Fostering Workplace Innovation and Labor-Management Partnership: The Challenge of Strategic Shifts in Business Operations at Pratt & Whitney (United Technologies)

Barrett, Betty January 2001 (has links)
The closing of the military jet engine side of the facility and laying off of more than half of the workforce was an unanticipated form of instability faced in this case. The study had begun in order to document innovations between the IAM local and local area management centering on establishing a team-based work system and joint training systems. While important as innovations, these efforts did not convince Connecticut managers to maintain the work in this location. Ultimately, neither local union or local management efforts were sufficient to overcome the instability associated with broad corporate strategies around the movement of work.

From Three to One: Integrating a High Performance Work Organization Process, Lean Production and Activity Based Costing Change Initiatives. Boeing Corporation, Wichita, Kansas, IAM, 2000.

Kochan, Thomas January 2000 (has links)
In 1997, Boeing and IAM launched an HPWO after introducing lean production initiatives in 1994 and Activity Based Costing (ABC) in 1996. Management and union leaders wanted to empower the workforce and enhance the competitiveness of the operations. After a slow and difficult path of diffusion, they need to decide how to best integrate these separate improvement programs into a single initiative. Boeing's engineering culture needs to work with the pragmatic workforce in Wichita. Workers fear losing products and projects to other Boeing facilities and have concerns about leadership turnover and follow-through. The HPWO helped managers recognize the importance of unions. Still, all three initiatives need a broader base of support.

A Decade of Learning: International Association of Machinists/Boeing Joint Programs. Seattle, Washington, 2001.

Kochan, Thomas January 2001 (has links)
This national joint training initiative, funded at 14 cents per payroll hour worked, represents a key institutional innovation. Negotiated under Article 20 of the contract, this program has evolved over its first decade of experience. It expands life long learning to nearly all hourly workers. Major components of the program include: Layoff and Redeployment assistance, The Health and Safety Institute; Career and Personal Development; Classroom Training; Personal Enrichment, and High Performance Work Organization (HPWO). After a decade, the joint programs have reached between 40 and 50% of bargaining unit employees. Lean initiatives at Boeing are largely separate from the National Joint Training programs. The joint training programs have attractive design features and a steady stream of funds - so perhaps they should be more tightly linked. The program is jointly governed and staffed and thereby provides shared ownership from management, the union and the workforce. Its full potential will only be realized, however, when line managers see it as a core resource.

Aerospace strategy for the aerospace nation

Wright, Stephen E. January 1900 (has links)
Thesis--School of Advanced Airpower Studies, Maxwell Air Force Base, Ala., 1992-93. / Title from title screen (viewed Nov. 7, 2003). "August 1994." Includes bibliographical references.

An experimental investigation of the effect of vortex generators on the aerodynamic characteristics of a NACA 0021 airfoil undergoing large amplitude pitch oscillations

Rueger, Mathew Lee January 1988 (has links)
No description available.

Flutter evaluation of an airfoil

Akbari, Mohammad Hadi January 1993 (has links)
The problem of flutter is first introduced. The equations of motion of an airfoil with two degrees of freedom, in pitch and plunge, are obtained. Then, the unsteady aerodynamic theories for different flow regimes are presented. The traditional solutions to the flutter problem, namely, the p-k and U-g methods, are formulated, and the Laplace transformation method for flutter analysis is also introduced. Then, the effect of different design parameters of an airfoil on the flutter speed is analyzed, both in the incompressible and transonic regimes. Furthermore, the effect of the relative values of the design parameters on the occurrence of flutter is investigated. Finally, some general conclusions regarding the above-mentioned phenomena are derived. The goal of this work is the fact that, the unsteady aerodynamic data has been used, both in the incompressible and transonic regimes, and, therefore, the obtained results are fairly precise.

Investigations on the dynamics of panels subjected to supersonic flow

Tang, Liaosha, 1970- January 2002 (has links)
A simply supported two-dimensional panel subjected to supersonic flow is numerically investigated using a Galerkin method, a finite-difference method and a proper orthogonal decomposition method. First-order linear piston theory is used to model the aerodynamic loads, and von Karman plate theory is applied to model the structural non-linearity. The panel is shown to be very rich in dynamics, including stable flat/buckled state, limit cycle oscillation, and chaos. The complexity of the dynamics of the panel is presented in a diagram of stability regions, Lyapunov exponents and two bifurcation diagrams with respect to the in-plane load and the flow velocity. Several new phenomena have been observed, including the co-existence of multiple symmetric limit cycles and the pairing of asymmetric limit cycles. Moreover, reduced order models of the aeroelastic system are constructed by means of proper orthogonal decomposition. The performance of the reduced order models with a striking low dimensionality is tested, and the reduced order models are shown to be accurate and robust for predicting the dynamics of the aeroelastic system.

An experimental investigation of flow over an oscillating airfoil /

Gerontakos, Panayiote January 2004 (has links)
The detailed behaviour of the unsteady boundary layer and stall events occurred on a sinusoidally oscillating NACA 0012 airfoil at Re = 1.35 x 105 was investigated experimentally by using closely-spaced multiple hot-film sensor arrays. The hot-film measurements were supplemented by surface pressure measurements, hot-wire wake velocity surveys and smoke-flow visualizations. Three typical oscillation parameters: attached flow, light stall, and deep stall were tested. Special attention was focused on the non-intrusive identification of the spatial-temporal progression of the locations of the boundary-layer transition and separation and reattachment points for a range of oscillation frequencies and amplitudes both prior to, during, and post the stall. The results show that for an unsteady airfoil, the reduced frequency of the oscillation was found to be highly significant and only small values of reduced frequency were required to delay the onset of the various boundary-layer events, and to produce significant variations and hysteresis in the peak values of lift and drag forces and the pitching moments, which are fundamentally different from their static counterparts. Lift stall was observed to occur when the leading-edge vortex reached 90% of the chord, while moment stall occurred at the end of the upward spread of the trailing-edge flow reversal. The convection speed of the leading-edge and the secondary vortices were also reported. Dynamic stall was found to be caused by an abrupt turbulent separation near the leading-edge region and not with the bursting of the laminar separation bubble, as is commonly observed for a static NACA 0012 airfoil; the result being the initiation, growth and convection of an energetic leading-edge vortex. Moreover, the detection of the sudden turbulent breakdown could serve as an indicator for dynamic stall detection and control. The results reported on here provide a deepened insight into the detailed nature of

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