WorldWideScience

Sample records for solid modeling aerospace

  1. Advanced fusion welding processes, solid state joining and a successful marriage. [production of aerospace structures

    Science.gov (United States)

    Miller, F. R.

    1972-01-01

    Joining processes for aerospace systems combine fusion welding and solid state joining during production of metal structures. Detailed characteristics of electron beam welding, plasma arc welding, diffusion welding, inertia welding and weldbond processes are discussed.

  2. Plasma Immersion Ion Implantation with Solid Targets for Space and Aerospace Applications

    International Nuclear Information System (INIS)

    Oliveira, R. M.; Goncalves, J. A. N.; Ueda, M.; Silva, G.; Baba, K.

    2009-01-01

    This paper describes successful results obtained by a new type of plasma source, named as Vaporization of Solid Targets (VAST), for treatment of materials for space and aerospace applications, by means of plasma immersion ion implantation and deposition (PIII and D). Here, the solid element is vaporized in a high pressure glow discharge, being further ionized and implanted/deposited in a low pressure cycle, with the aid of an extra electrode. First experiments in VAST were run using lithium as the solid target. Samples of silicon and aluminum alloy (2024) were immersed into highly ionized lithium plasma, whose density was measured by a double Langmuir probe. Measurements performed with scanning electron microscopy (SEM) showed clear modification of the cross-sectioned treated silicon samples. X-ray photoelectron spectroscopy (XPS) analysis revealed that lithium was implanted/deposited into/onto the surface of the silicon. Implantation depth profiles may vary according to the condition of operation of VAST. One direct application of this treatment concerns the protection against radiation damage for silicon solar cells. For the case of the aluminum alloy, X-ray diffraction analysis indicated the appearance of prominent new peaks. Surface modification of A12024 by lithium implantation/deposition can lower the coefficient of friction and improve the resistance to fatigue of this alloy. Recently, cadmium was vaporized and ionized in VAST. The main benefit of this element is associated with the improvement of corrosion resistance of metallic substrates. Besides lithium and cadmium, VAST allows to performing PIII and D with other species, leading to the modification of the near-surface of materials for distinct purposes, including applications in the space and aerospace areas.

  3. 75 FR 30282 - Airworthiness Directives; Quartz Mountain Aerospace, Inc. Model 11E Airplanes

    Science.gov (United States)

    2010-06-01

    ... Airworthiness Directives; Quartz Mountain Aerospace, Inc. Model 11E Airplanes AGENCY: Federal Aviation... airworthiness directive (AD) for all Quartz Mountain Aerospace, Inc. Model 11E airplanes. This AD requires you... reference of certain publications listed in this AD. ADDRESSES: Quartz Mountain Aerospace, Inc. is in...

  4. 75 FR 12468 - Airworthiness Directives; Quartz Mountain Aerospace, Inc. Model 11E Airplanes

    Science.gov (United States)

    2010-03-16

    ... Aerospace, Inc. Model 11E Airplanes AGENCY: Federal Aviation Administration (FAA), Department of... airworthiness directive (AD) for all Quartz Mountain Aerospace, Inc. Model 11E airplanes. This proposed AD would... 5 p.m., Monday through Friday, except Federal holidays. Quartz Mountain Aerospace, Inc. is in...

  5. 75 FR 61345 - Airworthiness Directives; Eclipse Aerospace, Inc. Model EA500 Airplanes

    Science.gov (United States)

    2010-10-05

    ... Airworthiness Directives; Eclipse Aerospace, Inc. Model EA500 Airplanes AGENCY: Federal Aviation Administration... service information identified in this AD, contact Eclipse Aerospace Incorporated, 2503 Clark Carr Loop... Kinney, Aerospace Engineer, Ft. Worth Aircraft Certification Office, FAA, 2601 Meacham Blvd., Fort Worth...

  6. 76 FR 71865 - Special Conditions: Gulfstream Aerospace Corporation, Model GVI Airplane; Windshield Coating in...

    Science.gov (United States)

    2011-11-21

    ...; Special Conditions No. 25-452-SC] Special Conditions: Gulfstream Aerospace Corporation, Model GVI Airplane... Aerospace Corporation Model GVI airplane. This airplane will have a novel or unusual design feature(s..., Gulfstream Aerospace Corporation (GAC) applied for an FAA type certificate for its new Model GVI passenger...

  7. A Surface Modeling Paradigm for Electromagnetic Applications in Aerospace Structures

    OpenAIRE

    Jha, RM; Bokhari, SA; Sudhakar, V; Mahapatra, PR

    1989-01-01

    A systematic approach has been developed to model the surfaces encountered in aerospace engineering for EM applications. The basis of this modeling is the quadric canonical shapes which are the coordinate surfaces of the Eisenhart Coordinate systems. The building blocks are visualized as sections of quadric cylinders and surfaces of revolution. These truncated quadrics can successfully model realistic aerospace structures which are termed a s hybrid quadrics, of which the satellite launch veh...

  8. 75 FR 20265 - Airworthiness Directives; Liberty Aerospace Incorporated Model XL-2 Airplanes

    Science.gov (United States)

    2010-04-19

    ... Office, 1701 Columbia Avenue, College Park, Georgia 30337; telephone: (404) 474-5524; facsimile: (404... Airworthiness Directives; Liberty Aerospace Incorporated Model XL-2 Airplanes AGENCY: Federal Aviation...-08- 05, which applies to certain Liberty Aerospace Incorporated Model XL-2 airplanes. AD 2009-08-05...

  9. Elements of a collaborative systems model within the aerospace industry

    Science.gov (United States)

    Westphalen, Bailee R.

    2000-10-01

    Scope and method of study. The purpose of this study was to determine the components of current aerospace collaborative efforts. There were 44 participants from two selected groups surveyed for this study. Nineteen were from the Oklahoma Air National Guard based in Oklahoma City representing the aviation group. Twenty-five participants were from the NASA Johnson Space Center in Houston representing the aerospace group. The surveys for the aviation group were completed in reference to planning missions necessary to their operations. The surveys for the aerospace group were completed in reference to a well-defined and focused goal from a current mission. A questionnaire was developed to survey active participants of collaborative systems in order to consider various components found within the literature. Results were analyzed and aggregated through a database along with content analysis of open-ended question comments from respondents. Findings and conclusions. This study found and determined elements of a collaborative systems model in the aerospace industry. The elements were (1) purpose or mission for the group or team; (2) commitment or dedication to the challenge; (3) group or team meetings and discussions; (4) constraints of deadlines and budgets; (5) tools and resources for project and simulations; (6) significant contributors to the collaboration; (7) decision-making formats; (8) reviews of project; (9) participants education and employment longevity; (10) cross functionality of team or group members; (11) training on the job plus teambuilding; (12) other key elements identified relevant by the respondents but not included in the model such as communication and teamwork; (13) individual and group accountability; (14) conflict, learning, and performance; along with (15) intraorganizational coordination. These elements supported and allowed multiple individuals working together to solve a common problem or to develop innovation that could not have been

  10. Path generation algorithm for UML graphic modeling of aerospace test software

    Science.gov (United States)

    Qu, MingCheng; Wu, XiangHu; Tao, YongChao; Chen, Chao

    2018-03-01

    Aerospace traditional software testing engineers are based on their own work experience and communication with software development personnel to complete the description of the test software, manual writing test cases, time-consuming, inefficient, loopholes and more. Using the high reliability MBT tools developed by our company, the one-time modeling can automatically generate test case documents, which is efficient and accurate. UML model to describe the process accurately express the need to rely on the path is reached, the existing path generation algorithm are too simple, cannot be combined into a path and branch path with loop, or too cumbersome, too complicated arrangement generates a path is meaningless, for aerospace software testing is superfluous, I rely on our experience of ten load space, tailor developed a description of aerospace software UML graphics path generation algorithm.

  11. NASA-UVA Light Aerospace Alloy and Structures Technology Program (LA2ST)

    Science.gov (United States)

    Gangloff, Richard P.; Starke, Edgar A., Jr.; Kelly, Robert G.; Scully, John R.; Shiflet, Gary J.; Stoner, Glenn E.; Wert, John A.

    1997-01-01

    The NASA-UVA Light Aerospace Alloy and Structures Technology (LA2ST) Program was initiated in 1986 and continues with a high level of activity. Here, we report on progress achieved between July I and December 31, 1996. The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light-weight aerospace alloys, composites and thermal gradient structures in collaboration with NASA-Langley researchers. Specific technical objectives are presented for each research project. We generally aim to produce relevant data and basic understanding of material mechanical response, environmental/corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement and modeling advances; and a pool of educated graduate students for aerospace technologies. The accomplishments presented in this report are summarized as follows. Three research areas are being actively investigated, including: (1) Mechanical and Environmental Degradation Mechanisms in Advanced Light Metals, (2) Aerospace Materials Science, and (3) Mechanics of Materials for Light Aerospace Structures.

  12. 76 FR 73483 - Airworthiness Directives; Gulfstream Aerospace Corporation Model GV and GV-SP Airplanes

    Science.gov (United States)

    2011-11-29

    ... Management Branch, ACE-102A, FAA, Atlanta Aircraft Certification Office (ACO), 1701 Columbia Avenue, College... Airworthiness Directives; Gulfstream Aerospace Corporation Model GV and GV-SP Airplanes AGENCY: Federal Aviation... certain Gulfstream Aerospace Corporation Model GV and GV-SP airplanes. This AD was prompted by...

  13. Water recovery and solid waste processing for aerospace and domestic applications. Volume 1: Final report

    Science.gov (United States)

    Murray, R. W.

    1973-01-01

    A comprehensive study of advanced water recovery and solid waste processing techniques employed in both aerospace and domestic or commercial applications is reported. A systems approach was used to synthesize a prototype system design of an advanced water treatment/waste processing system. Household water use characteristics were studied and modified through the use of low water use devices and a limited amount of water reuse. This modified household system was then used as a baseline system for development of several water treatment waste processing systems employing advanced techniques. A hybrid of these systems was next developed and a preliminary design was generated to define system and hardware functions.

  14. Outsourcing within aerospace manufacturing enterprises: A phenomenological study and outsourcing leadership model

    Science.gov (United States)

    Sampson, Enrique, Jr.

    Many aerospace workers believe transferring work projects abroad has an erosive effect on the U.S. aerospace industry (Pritchard, 2002). This qualitative phenomenological study examines factors for outsourcing decisions and the perceived effects of outsourcing on U.S. aerospace workers. The research sample consists of aerospace industry leaders and nonleaders from the East Coast, Midwest, and West Coast of the United States. Moustakas' modified van Kaam methods of analysis (1994) and Decision Explorer analysis software were applied to the interview transcripts. Resultant data identified five core themes: communication, best value, opportunities, cost, and offset consideration. The themes provided the framework for a model designed to assist leaders in making effective decisions and communicating the benefits of those decisions when considering outsourcing of work projects.

  15. 76 FR 41041 - Special Conditions: Gulfstream Aerospace LP (GALP) Model G250 Airplane, Interaction of Systems...

    Science.gov (United States)

    2011-07-13

    ... Conditions No. 25-439-SC] Special Conditions: Gulfstream Aerospace LP (GALP) Model G250 Airplane, Interaction... special conditions are issued for the Gulfstream Aerospace LP (GALP) Model G250 airplane. This airplane...

  16. 76 FR 81360 - Special Conditions: Gulfstream Aerospace LP (GALP) Model G280 Airplane, Operation Without Normal...

    Science.gov (United States)

    2011-12-28

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 25 [Docket No. FAA-2011-1172: Special Conditions No. 25-453-SC] Special Conditions: Gulfstream Aerospace LP (GALP) Model G280... Aerospace LP (GALP) Model G280 airplane. This airplane will have a novel or unusual design feature...

  17. 76 FR 25229 - Special Conditions: Gulfstream Aerospace LP (GALP) Model G250 Airplane, Dynamic Test Requirements...

    Science.gov (United States)

    2011-05-04

    ... Memorandum ``Side-Facing Seats on Transport Category Airplanes'' and draft Issue Paper ``Dynamic Test...; Special Conditions No. 25-425-SC] Special Conditions: Gulfstream Aerospace LP (GALP) Model G250 Airplane... are issued for the Gulfstream Aerospace LP (GALP) model G250 airplane. This airplane will have a novel...

  18. 76 FR 66660 - Special Conditions: Gulfstream Aerospace LP (GALP) Model G280 Airplane, Operation Without Normal...

    Science.gov (United States)

    2011-10-27

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 25 [Docket No. FAA-2011-1172: Notice No. 25-11-17-SC] Special Conditions: Gulfstream Aerospace LP (GALP) Model G280 Airplane... Aerospace LP (GALP) Model G280 airplane. This airplane will have a novel or unusual design feature...

  19. Model Development and Process Analysis for Lean Cellular Design Planning in Aerospace Assembly and Manufacturing

    Science.gov (United States)

    Hilburn, Monty D.

    Successful lean manufacturing and cellular manufacturing execution relies upon a foundation of leadership commitment and strategic planning built upon solid data and robust analysis. The problem for this study was to create and employ a simple lean transformation planning model and review process that could be used to identify functional support staff resources required to plan and execute lean manufacturing cells within aerospace assembly and manufacturing sites. The lean planning model was developed using available literature for lean manufacturing kaizen best practices and validated through a Delphi panel of lean experts. The resulting model and a standardized review process were used to assess the state of lean transformation planning at five sites of an international aerospace manufacturing and assembly company. The results of the three day, on-site review were compared with baseline plans collected from each of the five sites to determine if there analyzed, with focus on three critical areas of lean planning: the number and type of manufacturing cells identified, the number, type, and duration of planned lean and continuous kaizen events, and the quantity and type of functional staffing resources planned to support the kaizen schedule. Summarized data of the baseline and on-site reviews was analyzed with descriptive statistics. ANOVAs and paired-t tests at 95% significance level were conducted on the means of data sets to determine if null hypotheses related to cell, kaizen event, and support resources could be rejected. The results of the research found significant differences between lean transformation plans developed by site leadership and plans developed utilizing the structured, on-site review process and lean transformation planning model. The null hypothesis that there was no difference between the means of pre-review and on-site cell counts was rejected, as was the null hypothesis that there was no significant difference in kaizen event plans. These

  20. Modelling solid solutions with cluster expansion, special quasirandom structures, and thermodynamic approaches

    Science.gov (United States)

    Saltas, V.; Horlait, D.; Sgourou, E. N.; Vallianatos, F.; Chroneos, A.

    2017-12-01

    Modelling solid solutions is fundamental in understanding the properties of numerous materials which are important for a range of applications in various fields including nanoelectronics and energy materials such as fuel cells, nuclear materials, and batteries, as the systematic understanding throughout the composition range of solid solutions for a range of conditions can be challenging from an experimental viewpoint. The main motivation of this review is to contribute to the discussion in the community of the applicability of methods that constitute the investigation of solid solutions computationally tractable. This is important as computational modelling is required to calculate numerous defect properties and to act synergistically with experiment to understand these materials. This review will examine in detail two examples: silicon germanium alloys and MAX phase solid solutions. Silicon germanium alloys are technologically important in nanoelectronic devices and are also relevant considering the recent advances in ternary and quaternary groups IV and III-V semiconductor alloys. MAX phase solid solutions display a palette of ceramic and metallic properties and it is anticipated that via their tuning they can have applications ranging from nuclear to aerospace industries as well as being precursors for particular MXenes. In the final part, a brief summary assesses the limitations and possibilities of the methodologies discussed, whereas there is discussion on the future directions and examples of solid solution systems that should prove fruitful to consider.

  1. 78 FR 11089 - Special Conditions: Bombardier Aerospace, Model BD-500-1A10 and BD-500-1A11 Airplanes; Sidestick...

    Science.gov (United States)

    2013-02-15

    ...; Special Conditions No. 25-477-SC] Special Conditions: Bombardier Aerospace, Model BD-500-1A10 and BD-500... special conditions. SUMMARY: These special conditions are issued for the Bombardier Aerospace Model BD-500...: Background On December 10, 2009, Bombardier Aerospace applied for a type certificate for their new Model BD...

  2. NASA-UVA light aerospace alloy and structures technology program (LA(sup 2)ST)

    Science.gov (United States)

    Gangloff, Richard P.; Haviland, John K.; Herakovich, Carl T.; Pilkey, Walter D.; Pindera, Marek-Jerzy; Scully, John R.; Starke, Edgar A., Jr.; Stoner, Glenn E.; Thornton, Earl A.; Wawner, Franklin E., Jr.

    1992-01-01

    The general objective of the Light Aerospace Alloy and Structures Technology (LA(sup 2)ST) Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites, and thermal gradient structures in collaboration with Langley researchers. Specific technical objectives are established for each research project. We aim to produce relevant data and basic understanding of material behavior and microstructure, new monolithic and composite alloys, advanced processing methods, new solid and fluid mechanics analyses, measurement advances, and critically, a pool of educated graduate students for aerospace technologies. Four research areas are being actively investigated, including: (1) Mechanical and Environmental Degradation Mechanisms in Advanced Light Metals and Composites; (2) Aerospace Materials Science; (3) Mechanics of Materials and Composites for Aerospace Structures; and (4) Thermal Gradient Structures.

  3. Aerospace Technology (Aerospace Engineering Degree)

    OpenAIRE

    Tiseira Izaguirre, Andrés Omar; Blanco Rodríguez, David; Carreres Talens, Marcos; FAJARDO PEÑA, PABLO

    2013-01-01

    Apuntes de la asignatura Tecnología Aeroespacial Tiseira Izaguirre, AO.; Blanco Rodríguez, D.; Carreres Talens, M.; Fajardo Peña, P. (2013). Aerospace Technology (Aerospace Engineering Degree). Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/35263

  4. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 12: The diffusion of federally funded aerospace research and development (R/D) and the information seeking behavior of US aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.

    1991-01-01

    In this paper, the diffusion of federally funded aerospace R&D is explored from the perspective of the information-seeking behavior of U.S. aerospace engineers and scientists. The following three assumptions frame this exploration: (1) knowledge production, transfer, and utilization are equally important components of the aerospace R&D process; (2) the diffusion of knowledge resulting from federally funded aerospace R&D is indispensable for the U.S. to remain a world leader in aerospace; and (3) U.S. government technical reports, produced by NASA and DOD, play an important, but as yet undefined, role in the diffusion of federally funded aerospace R&D. A conceptual model for federally funded aerospace knowledge diffusion, one that emphasizes U.S. goverment technical reports, is presented. Data regarding three research questions concerning the information-seeking behavior of U.S. aerospace engineers and scientists are also presented.

  5. 77 FR 69568 - Special Conditions: Bombardier Aerospace, Model BD-500-1A10 and BD-500-1A11 Airplanes; Sidestick...

    Science.gov (United States)

    2012-11-20

    ... Aerospace, Model BD-500-1A10 and BD-500-1A11 Airplanes; Sidestick Controllers AGENCY: Federal Aviation... conditions for the Bombardier Aerospace Model BD-500-1A10 and BD-500-1A11 airplanes. These airplanes will... on the comments we receive. Background On December 10, 2009, Bombardier Aerospace applied for a type...

  6. Modeling Flight: The Role of Dynamically Scaled Free-Flight Models in Support of NASA's Aerospace Programs

    Science.gov (United States)

    Chambers, Joseph

    2010-01-01

    The state of the art in aeronautical engineering has been continually accelerated by the development of advanced analysis and design tools. Used in the early design stages for aircraft and spacecraft, these methods have provided a fundamental understanding of physical phenomena and enabled designers to predict and analyze critical characteristics of new vehicles, including the capability to control or modify unsatisfactory behavior. For example, the relatively recent emergence and routine use of extremely powerful digital computer hardware and software has had a major impact on design capabilities and procedures. Sophisticated new airflow measurement and visualization systems permit the analyst to conduct micro- and macro-studies of properties within flow fields on and off the surfaces of models in advanced wind tunnels. Trade studies of the most efficient geometrical shapes for aircraft can be conducted with blazing speed within a broad scope of integrated technical disciplines, and the use of sophisticated piloted simulators in the vehicle development process permits the most important segment of operations the human pilot to make early assessments of the acceptability of the vehicle for its intended mission. Knowledgeable applications of these tools of the trade dramatically reduce risk and redesign, and increase the marketability and safety of new aerospace vehicles. Arguably, one of the more viable and valuable design tools since the advent of flight has been testing of subscale models. As used herein, the term "model" refers to a physical article used in experimental analyses of a larger full-scale vehicle. The reader is probably aware that many other forms of mathematical and computer-based models are also used in aerospace design; however, such topics are beyond the intended scope of this document. Model aircraft have always been a source of fascination, inspiration, and recreation for humans since the earliest days of flight. Within the scientific

  7. 76 FR 70042 - Airworthiness Directives; Pacific Aerospace Limited Airplanes

    Science.gov (United States)

    2011-11-10

    ... Airworthiness Directives; Pacific Aerospace Limited Airplanes AGENCY: Federal Aviation Administration (FAA... directive (AD) for Pacific Aerospace Limited Model FU24 Airplanes. This AD results from mandatory continuing... Schletzbaum, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri...

  8. 78 FR 72554 - Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes

    Science.gov (United States)

    2013-12-03

    ... Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes AGENCY: Federal Aviation Administration... Gulfstream Aerospace Corporation Model GV and GV-SP airplanes. This AD was prompted by reports of two... Aerospace Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, GA 31402-2206; telephone 800...

  9. 78 FR 9781 - Airworthiness Directives; Pacific Aerospace Limited Airplanes

    Science.gov (United States)

    2013-02-12

    ... Airworthiness Directives; Pacific Aerospace Limited Airplanes AGENCY: Federal Aviation Administration (FAA... directive (AD) for all Pacific Aerospace Limited Models FU24-954 and FU24A-954 airplanes. This AD results... Aerospace Limited, Hamilton Airport, Private Bag, 3027 Hamilton, New Zealand; telephone: +64 7 843 6144; fax...

  10. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 45; The Technical Communications Practices of US Aerospace Engineers and Scientists: Results of the Phase 3 US Aerospace Engineering Educators Survey

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1996-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. Little is also known about the intermediary-based system that is used to transfer the results of federally funded R&D to the U.S. aerospace industry. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports, present a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis the technical communication practices of U.S. aerospace engineers and scientists who were members of the American Institute of Aeronautics and Astronautics (AIAA) and identified themselves as educators.

  11. Spectroscopic Challenges in the Modelling and Diagnostics of High Temperature Air Plasma Radiation for Aerospace Applications

    International Nuclear Information System (INIS)

    Laux, Christophe O.

    2007-01-01

    State-of-the-art spectroscopic models of the radiative transitions of interest for Earth re-entry and ground-based diagnostic facilities for aerospace applications are reviewed. The spectral range considered extends from the vacuum ultraviolet to the mid-infrared range (80 nm to 5.5 μm). The modeling results are compared with absolute intensity measurements of the ultraviolet-visible-infrared emission of a well-characterized high-temperature air plasma produced with a 50 kW inductively coupled radio-frequency plasma torch, and with high-resolution absorption spectra from the Center for Astrophysics in the vacuum ultraviolet. The Spectroscopic data required to better model the spectral features of interest for aerospace applications are discussed

  12. Study on the control mechanism of China aerospace enterprises' binary multinational operation

    Institute of Scientific and Technical Information of China (English)

    Wang Jian; Li Hanling; Wu Weiwei

    2008-01-01

    China's aerospace enterprises carry on the multinational operation and participate in the international competition and the international division of labor and cooperation positively.This article first analyzs China aerospace enterprises' binary multinational business control objective and constructes its model.Then the article analyzes the tangible and intangible control mechanism of China aerospace enterprises' binary multinational operation respectively.Finally,the article constructs the model of China aerospace enterprises' binary multinational operation mechanisms.

  13. Aerospace Medicine

    Science.gov (United States)

    Michaud, Vince

    2015-01-01

    NASA Aerospace Medicine overview - Aerospace Medicine is that specialty area of medicine concerned with the determination and maintenance of the health, safety, and performance of those who fly in the air or in space.

  14. NASA-UVA Light Aerospace Alloy and Structures Technology Program: LA(2)ST

    Science.gov (United States)

    Gangloff, Richard P.; Haviland, John K.; Herakovich, Carl T.; Pilkey, Walter D.; Pindera, Marek-Jerzy; Scully, John R.; Stoner, Glenn E.; Thornton, Earl A.; Wawner, Franklin E., Jr.; Wert, John A.

    1993-01-01

    The NASA-UVA Light Aerospace Alloy and Structures Technology (LA(2)ST) Program continues a high level of activity, with projects being conducted by graduate students and faculty advisors in the Departments of Materials Science and Engineering, Civil Engineering and Applied Mechanics, and Mechanical and Aerospace Engineering at the University of Virginia. This work is funded by the NASA-Langley Research Center under Grant NAG-1-745. We report on progress achieved between July 1 and December 31, 1992. The objective of the LA(2)ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites and thermal gradient structures in collaboration with NASA-Langley researchers. Specific technical objectives are presented for each research project. We generally aim to produce relevant data and basic understanding of material mechanical response, corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; new solid and fluid mechanics analyses; measurement advances; and critically, a pool of educated graduate students for aerospace technologies.

  15. 76 FR 36392 - Airworthiness Directives; Gulfstream Aerospace Corporation Model GV and GV-SP Airplanes

    Science.gov (United States)

    2011-06-22

    ... Aircraft Certification Office (ACO) 1701 Columbia Avenue, College Park, Georgia 30337; phone: 404-474-5566..., Atlanta Aircraft Certification Office (ACO) 1701 Columbia Avenue, College Park, Georgia 30337; telephone... Aerospace Corporation Model GV and GV-SP Airplanes AGENCY: Federal Aviation Administration (FAA), DOT...

  16. Knowledge-based diagnosis for aerospace systems

    Science.gov (United States)

    Atkinson, David J.

    1988-01-01

    The need for automated diagnosis in aerospace systems and the approach of using knowledge-based systems are examined. Research issues in knowledge-based diagnosis which are important for aerospace applications are treated along with a review of recent relevant research developments in Artificial Intelligence. The design and operation of some existing knowledge-based diagnosis systems are described. The systems described and compared include the LES expert system for liquid oxygen loading at NASA Kennedy Space Center, the FAITH diagnosis system developed at the Jet Propulsion Laboratory, the PES procedural expert system developed at SRI International, the CSRL approach developed at Ohio State University, the StarPlan system developed by Ford Aerospace, the IDM integrated diagnostic model, and the DRAPhys diagnostic system developed at NASA Langley Research Center.

  17. 77 FR 54787 - Airworthiness Directives; M7 Aerospace LLC Airplanes

    Science.gov (United States)

    2012-09-06

    ... Airworthiness Directives; M7 Aerospace LLC Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... Aerospace LLC Models SA226-AT, SA226-T, SA226-T(B), SA226-TC, SA227-AC (C-26A), SA227-BC (C-26A), SA227-CC..., contact M7 Aerospace LP, 10823 NE Entrance Road, San Antonio, Texas 78216; phone: (210) 824- 9421; fax...

  18. Automated Modeling and Simulation Using the Bond Graph Method for the Aerospace Industry

    Science.gov (United States)

    Granda, Jose J.; Montgomery, Raymond C.

    2003-01-01

    Bond graph modeling was originally developed in the late 1950s by the late Prof. Henry M. Paynter of M.I.T. Prof. Paynter acted well before his time as the main advantage of his creation, other than the modeling insight that it provides and the ability of effectively dealing with Mechatronics, came into fruition only with the recent advent of modern computer technology and the tools derived as a result of it, including symbolic manipulation, MATLAB, and SIMULINK and the Computer Aided Modeling Program (CAMPG). Thus, only recently have these tools been available allowing one to fully utilize the advantages that the bond graph method has to offer. The purpose of this paper is to help fill the knowledge void concerning its use of bond graphs in the aerospace industry. The paper first presents simple examples to serve as a tutorial on bond graphs for those not familiar with the technique. The reader is given the basic understanding needed to appreciate the applications that follow. After that, several aerospace applications are developed such as modeling of an arresting system for aircraft carrier landings, suspension models used for landing gears and multibody dynamics. The paper presents also an update on NASA's progress in modeling the International Space Station (ISS) using bond graph techniques, and an advanced actuation system utilizing shape memory alloys. The later covers the Mechatronics advantages of the bond graph method, applications that simultaneously involves mechanical, hydraulic, thermal, and electrical subsystem modeling.

  19. 76 FR 65105 - Special Conditions: Gulfstream Aerospace Corporation, Model GIV-X Airplane; Isolation or Aircraft...

    Science.gov (United States)

    2011-10-20

    ...-1140; Special Conditions No. 25-450-SC] Special Conditions: Gulfstream Aerospace Corporation, Model GIV-X Airplane; Isolation or Aircraft Electronic System Security Protection From Unauthorized Internal Access AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final special conditions; request for...

  20. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 34: How early career-stage US aerospace engineers and scientists produce and use information

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1995-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis the production and use of information by U.S. aerospace engineers and scientists who had changed their American Institute of Aeronautics and Astronautics (AIAA) membership from student to professional in the past five years.

  1. Advanced Engineering Environments: Implications for Aerospace Manufacturing

    Science.gov (United States)

    Thomas, D.

    2001-01-01

    There are significant challenges facing today's aerospace industry. Global competition, more complex products, geographically-distributed design teams, demands for lower cost, higher reliability and safer vehicles, and the need to incorporate the latest technologies quicker all face the developer of aerospace systems. New information technologies offer promising opportunities to develop advanced engineering environments (AEEs) to meet these challenges. Significant advances in the state-of-the-art of aerospace engineering practice are envisioned in the areas of engineering design and analytical tools, cost and risk tools, collaborative engineering, and high-fidelity simulations early in the development cycle. These advances will enable modeling and simulation of manufacturing methods, which will in turn allow manufacturing considerations to be included much earlier in the system development cycle. Significant cost savings, increased quality, and decreased manufacturing cycle time are expected to result. This paper will give an overview of the NASA's Intelligent Synthesis Environment, the agency initiative to develop an AEE, with a focus on the anticipated benefits in aerospace manufacturing.

  2. Intersubjective management in aerospace engineering

    Directory of Open Access Journals (Sweden)

    Arpentieva Mariam

    2017-01-01

    Full Text Available This article presents a postnonclassical approach to create the science of management processes organization in a developing society, the focus of which is “the man of culture”, i.e. the man, not just adhering to cultural norms, but also creating new concepts and products of culture. This science is proposed to be called Evergetics. The purpose of the study is the analysis science of management processes organization in a developing aerospace engineering and other industrial areas of society. The authors describe the main aspects and procedures evergetics management in aerospace engineering. They uses the comparison method, compares classical and modern approaches and technologies of management. In evergetics management model each member of society or organization is interested in augmenting his cultural heritage he is producing, which entails a raise of stability in process of engineering actions and a raise cultural potential of the society as a whole and, as a consequence, an increase in the proportion of moral and ethical managerial decisions and corresponding to them benevolent actions in organizational life. Summarize the article’s main findings, authors may in some main conclusions about necessity evergetics model and intersubjective technologies in the creation and development of aerospace engineering.

  3. Aerospace Activities in the Elementary School

    Science.gov (United States)

    Jones, Robert M.; Wiggins, Kenneth E.

    1974-01-01

    Describes 17 activities which are aerospace oriented and yet provide an interdisciplinary approach to learning. Some of the activities described involve paper airplanes, parachutes, model rockets, etc. (BR)

  4. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 23: The communications practices of US aerospace engineering faculty and students: Results of the phase 3 survey

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis U.S. aerospace engineering faculty and students.

  5. High-Fidelity Simulation in Biomedical and Aerospace Engineering

    Science.gov (United States)

    Kwak, Dochan

    2005-01-01

    Contents include the following: Introduction / Background. Modeling and Simulation Challenges in Aerospace Engineering. Modeling and Simulation Challenges in Biomedical Engineering. Digital Astronaut. Project Columbia. Summary and Discussion.

  6. Aerospace Transparency Research Compendium

    National Research Council Canada - National Science Library

    Pinkus, Alan

    2003-01-01

    ... (ARRL), located at Wright-Patterson AFB OH, has advanced aerospace transparency technology through the investigative research of numerous optical and visual parameters inherent in aerospace transparencies...

  7. 78 FR 11567 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Science.gov (United States)

    2013-02-19

    ... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Model Gulfstream G150... Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.): Amendment 39...

  8. 76 FR 70040 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Science.gov (United States)

    2011-11-10

    ... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Aerospace LP (type certificate previously held by Israel Aircraft Industries, Ltd.) Model Galaxy and... new AD: 2011-23-07 Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft...

  9. Study of Delft aerospace alumni

    NARCIS (Netherlands)

    Smits, G.N.

    2008-01-01

    This thesis reports on an alumni study of the Faculty Aerospace Engineering at Delft University of Technology to discover what the impact is of the degree in aerospace engineering on an alumnus' professional success and comment on what are important qualities for aerospace engineers to have in order

  10. Didactic communication in the training of specialists in aerospace engineering

    Directory of Open Access Journals (Sweden)

    Arpentieva Mariam

    2018-01-01

    Full Text Available The article is devoted to the study of the problems of didactic communication in the training of engineering personnel for the aerospace industry and to the study of the problems of the communication of subjects concerning the training and education of highly qualified engineering personnel for the aerospace industry. In the training of engineering personnel for the aerospace industry the integrated model of didactic communication involves the identification and description of its various components, typical modes of interaction (modes that reflect different aspects of the person's understanding of the world around him and himself in the process of different types of education and upbringing. Didactic communication in the process of training engineering personnel for the aerospace industry is a multi-level, multi-stage and multi-component phenomenon. The modes, possibilities and limitations of this communication are related to the level and direction of personal, interpersonal and professional development of interaction subjects. The productivity of preparing engineering personnel for the aerospace industry is related to the choice of a model of didactic communication, which is addressed in different ways to the development of cognitive, value-semantic and meta-cognitive structures that form one or another type of education and upbringing.

  11. Aerospace Accident - Injury Autopsy Data System -

    Data.gov (United States)

    Department of Transportation — The Aerospace Accident Injury Autopsy Database System will provide the Civil Aerospace Medical Institute (CAMI) Aerospace Medical Research Team (AMRT) the ability to...

  12. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 41: Technical communication practices of Dutch and US aerospace engineers and scientists: International perspective on aerospace

    Science.gov (United States)

    Barclay, Rebecca O.; Pinelli, Thomas E.; Kennedy, John M.

    1994-01-01

    As part of Phase 4 of the NASA/DOD Aerospace Knowledge Diffusion Research Project, studies were conducted that investigated the technical communications practices of Dutch and U.S. aerospace engineers and scientists. The studies had the following objectives: (1) to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communication to their professions, (2) to determine the use and production of technical communication by aerospace engineers and scientists, (3) to investigate their use of libraries and technical information centers, (4) to investigate their use of and the importance to them of computer and information technology, (5) to examine their use of electronic networks, and (6) to determine their use of foreign and domestically produced technical reports. Self-administered (mail) questionnaires were distributed to Dutch aerospace engineers and scientists at the National Aerospace Laboratory (NLR) in the Netherlands, the NASA Ames Research Center in the U.S., and the NASA Langley Research Center in the U.S. Responses of the Dutch and U.S. participants to selected questions are presented in this paper.

  13. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 24: The technical communications practices of US aerospace engineers and scientists: Results of the phase 1 SAE mail survey

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis the technical communications practices of U.S. aerospace engineers and scientists affiliated with the Society of Automotive Engineers (SAE).

  14. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report number 21: US aerospace industry librarians and technical information specialists as information intermediaries: Results of the phase 2 survey

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DoD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis U.S. aerospace industry librarians and technical information specialists as information intermediaries.

  15. NASA Perspective and Modeling of Thermal Runaway Propagation Mitigation in Aerospace Batteries

    Science.gov (United States)

    Shack, P.; Iannello, C.; Rickman, S.; Button, R.

    2014-01-01

    NASA has traditionally sought to reduce the likelihood of a single cell thermal runaway (TR) in their aerospace batteries to an absolute minimum by employing rigorous screening program of the cells. There was generally a belief that TR propagation resulting in catastrophic failure of the battery was a forgone conclusion for densely packed aerospace lithium-ion batteries. As it turns out, this may not be the case. An increasing number of purportedly TR propagation-resistant batteries are appearing among NASA partners in the commercial sector and the Department of Defense. In the recent update of the battery safety standard (JSC 20793) to address this paradigm shift, the NASA community included requirements for assessing TR severity and identifying simple, low-cost severity reduction measures. Unfortunately, there are no best-practice guidelines for this work in the Agency, so the first project team attempting to meet these requirements would have an undue burden placed upon them. A NASA engineering Safety Center (NESC) team set out to perform pathfinding activities for meeting those requirements. This presentation will provide contextual background to this effort, as well as initial results in attempting to model and simulate TR heat transfer and propagation within battery designs.

  16. Experimental investigation of solid rocket motors for small sounding rockets

    Science.gov (United States)

    Suksila, Thada

    2018-01-01

    Experimentation and research of solid rocket motors are important subjects for aerospace engineering students. However, many institutes in Thailand rarely include experiments on solid rocket motors in research projects of aerospace engineering students, mainly because of the complexity of mixing the explosive propellants. This paper focuses on the design and construction of a solid rocket motor for total impulse in the class I-J that can be utilised as a small sounding rocket by researchers in the near future. Initially, the test stands intended for measuring the pressure in the combustion chamber and the thrust of the solid rocket motor were designed and constructed. The basic design of the propellant configuration was evaluated. Several formulas and ratios of solid propellants were compared for achieving the maximum thrust. The convenience of manufacturing and casting of the fabricated solid rocket motors were a critical consideration. The motor structural analysis such as the combustion chamber wall thickness was also discussed. Several types of nozzles were compared and evaluated for ensuring the maximum thrust of the solid rocket motors during the experiments. The theory of heat transfer analysis in the combustion chamber was discussed and compared with the experimental data.

  17. Aerospace dermatology

    Directory of Open Access Journals (Sweden)

    Sandeep Arora

    2017-01-01

    Full Text Available Evolutionarily, man is a terrestrial mammal, adapted to land. Aviation and now space/microgravity environment, hence, pose new challenges to our physiology. Exposure to these changes affects the human body in acute and chronic settings. Since skin reflects our mental and physical well-being, any change/side effects of this environment shall be detected on the skin. Aerospace industry offers a unique environment with a blend of all possible occupational disorders, encompassing all systems of the body, particularly the skin. Aerospace dermatologists in the near future shall be called upon for their expertise as we continue to push human physiological boundaries with faster and more powerful military aircraft and look to colonize space stations and other planets. Microgravity living shall push dermatology into its next big leap-space, the final frontier. This article discusses the physiological effects of this environment on skin, effect of common dermatoses in aerospace environment, effect of microgravity on skin, and occupational hazards of this industry.

  18. Aerospace Dermatology.

    Science.gov (United States)

    Arora, Sandeep

    2017-01-01

    Evolutionarily, man is a terrestrial mammal, adapted to land. Aviation and now space/microgravity environment, hence, pose new challenges to our physiology. Exposure to these changes affects the human body in acute and chronic settings. Since skin reflects our mental and physical well-being, any change/side effects of this environment shall be detected on the skin. Aerospace industry offers a unique environment with a blend of all possible occupational disorders, encompassing all systems of the body, particularly the skin. Aerospace dermatologists in the near future shall be called upon for their expertise as we continue to push human physiological boundaries with faster and more powerful military aircraft and look to colonize space stations and other planets. Microgravity living shall push dermatology into its next big leap-space, the final frontier. This article discusses the physiological effects of this environment on skin, effect of common dermatoses in aerospace environment, effect of microgravity on skin, and occupational hazards of this industry.

  19. 75 FR 10694 - Airworthiness Directives; AeroSpace Technologies of Australia Pty Ltd Models N22B, N22S, and N24A...

    Science.gov (United States)

    2010-03-09

    ... Airworthiness Directives; AeroSpace Technologies of Australia Pty Ltd Models N22B, N22S, and N24A Airplanes... authority for Australia, has issued AD GAF-N22-52, Amendment 1, dated January 2010 (referred to after this... examining the MCAI in the AD docket. Relevant Service Information AeroSpace Technologies of Australia...

  20. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 39: The role of computer networks in aerospace engineering

    Science.gov (United States)

    Bishop, Ann P.; Pinelli, Thomas E.

    1994-01-01

    This paper presents selected results from an empirical investigation into the use of computer networks in aerospace engineering. Such networks allow aerospace engineers to communicate with people and access remote resources through electronic mail, file transfer, and remote log-in. The study drew its subjects from private sector, government and academic organizations in the U.S. aerospace industry. Data presented here were gathered in a mail survey, conducted in Spring 1993, that was distributed to aerospace engineers performing a wide variety of jobs. Results from the mail survey provide a snapshot of the current use of computer networks in the aerospace industry, suggest factors associated with the use of networks, and identify perceived impacts of networks on aerospace engineering work and communication.

  1. Aerospace engineering educational program

    Science.gov (United States)

    Craft, William; Klett, David; Lai, Steven

    1992-01-01

    The principle goal of the educational component of NASA CORE is the creation of aerospace engineering options in the mechanical engineering program at both the undergraduate and graduate levels. To accomplish this goal, a concerted effort during the past year has resulted in detailed plans for the initiation of aerospace options in both the BSME and MSME programs in the fall of 1993. All proposed new courses and the BSME aerospace option curriculum must undergo a lengthy approval process involving two cirriculum oversight committees (School of Engineering and University level) and three levels of general faculty approval. Assuming approval is obtained from all levels, the options will officially take effect in Fall '93. In anticipation of this, certain courses in the proposed curriculum are being offered during the current academic year under special topics headings so that current junior level students may graduate in May '94 under the BSME aerospace option. The proposed undergraduate aerospace option curriculum (along with the regular mechanical engineering curriculum for reference) is attached at the end of this report, and course outlines for the new courses are included in the appendix.

  2. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 25: The technical communications practices of British aerospace engineers and scientists: Results of the phase 4 RAeS mail survey

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis the technical communications practices of British aerospace engineers and scientists.

  3. Nickel hydrogen and silver zinc battery cell modeling at the Aerospace Corporation

    Energy Technology Data Exchange (ETDEWEB)

    Zimmerman, A.H.

    1996-02-01

    A nickel hydrogen battery cell model has been fully developed and implemented at The Aerospace Corporation. Applications of this model to industry needs for the design of better cells, power system design and charge control thermal management, and long-term performance trends will be described. Present efforts will be described that are introducing the silver and zinc electrode reactions into this model architecture, so that the model will be able to predict performance for not only silver zinc cells, but also nickel zinc, silver hydrogen, and silver cadmium cells. The silver zinc cell modeling effort is specifically designed to address the concerns that arise most often in launch vehicle applications: transient response, power-on voltage regulation, hot or cold operation, electrolyte spewing, gas venting, self-discharge, separator oxidation, and oxalate crystal growth. The specific model features that are being employed to address these issues will be described.

  4. 75 FR 28485 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Science.gov (United States)

    2010-05-21

    ... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.): Amendment 39... previously held by Israel Aircraft Industries, Ltd.) Model Gulfstream 100 airplanes; and Model Astra SPX and...

  5. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 33: The technical communications practices of US aerospace engineers and scientists: Results of the phase 1 AIAA mail survey

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1995-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis the technical communications practices of U.S. aerospace engineers and scientists who are members of the American Institute of Aeronautics and Astronautics (AIAA).

  6. RISC-type microprocessors may revolutionize aerospace simulation

    Science.gov (United States)

    Jackson, Albert S.

    The author explores the application of RISC (reduced instruction set computer) processors in massively parallel computer (MPC) designs for aerospace simulation. The MPC approach is shown to be well adapted to the needs of aerospace simulation. It is shown that any of the three common types of interconnection schemes used with MPCs are effective for general-purpose simulation, although the bus-or switch-oriented machines are somewhat easier to use. For partial differential equation models, the hypercube approach at first glance appears more efficient because the nearest-neighbor connections required for three-dimensional models are hardwired in a hypercube machine. However, the data broadcast ability of a bus system, combined with the fact that data can be transmitted over a bus as soon as it has been updated, makes the bus approach very competitive with the hypercube approach even for these types of models.

  7. A Decision-Making Model for Evaluating and Selecting Suppliers for the Sustainable Operation and Development of Enterprises in the Aerospace Industry

    Directory of Open Access Journals (Sweden)

    Chin-Tsai Lin

    2018-03-01

    Full Text Available Due to rigorous quality requirements and high unit prices, the manufacture of machines used in the aerospace industry is characterized by a high entry threshold, high risk and a long payback period. A good decision-making model for evaluating and selecting suppliers is vital for sustainable enterprise development. Therefore, this study presents a new two-stage model for evaluating and selecting suppliers in the aerospace industry. In the first stage, a hierarchical structure is built with five main and 16 sub-criteria for supplier evaluation and selection following the modified Delphi method; in the second stage, the best alternative solution is selected following the analytic network process (ANP method. Finally, this study verifies the feasibility of the above model based on the purchase of high-precision and high-cost 3D measuring tools by Aerowin Technology Corporation, which is listed on the Taiwan Stock Exchange. The results show that the five criteria in the above model are ranked by their degree of importance, as follows: quality > cost > delivery > marketing > organizational planning. The findings of this research can be used as a reference for decision-making during the purchase of high-precision and high-priced machine tools in the aerospace industry.

  8. Aerospace Systems Monitor, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Proposal Title: Aerospace Systems Monitor PHASE 1 Technical Abstract: This Phase II STTR project will continue development and commercialization of the Aerospace...

  9. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 31: The technical communications practices of US aerospace engineers and scientists: Results of the phase 1 SME mail survey

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical communications practices of U.S. aerospace engineers and scientists affiliated with, not necessarily belonging to, the Society of Manufacturing Engineers (SME).

  10. Bayesian model for matching the radiometric measurements of aerospace and field ocean color sensors.

    Science.gov (United States)

    Salama, Mhd Suhyb; Su, Zhongbo

    2010-01-01

    A Bayesian model is developed to match aerospace ocean color observation to field measurements and derive the spatial variability of match-up sites. The performance of the model is tested against populations of synthesized spectra and full and reduced resolutions of MERIS data. The model derived the scale difference between synthesized satellite pixel and point measurements with R(2) > 0.88 and relative error < 21% in the spectral range from 400 nm to 695 nm. The sub-pixel variabilities of reduced resolution MERIS image are derived with less than 12% of relative errors in heterogeneous region. The method is generic and applicable to different sensors.

  11. Bayesian Model for Matching the Radiometric Measurements of Aerospace and Field Ocean Color Sensors

    Directory of Open Access Journals (Sweden)

    Mhd. Suhyb Salama

    2010-08-01

    Full Text Available A Bayesian model is developed to match aerospace ocean color observation tofield measurements and derive the spatial variability of match-up sites. The performance of the model is tested against populations of synthesized spectra and full and reduced resolutions of MERIS data. The model derived the scale difference between synthesized satellite pixel and point measurements with R2 > 0.88 and relative error < 21% in the spectral range from 400 nm to 695 nm. The sub-pixel variabilities of reduced resolution MERIS image are derived with less than 12% of relative errors in heterogeneous region. The method is generic and applicable to different sensors.

  12. Structural assessment of aerospace components using image processing algorithms and Finite Element models

    DEFF Research Database (Denmark)

    Stamatelos, Dimtrios; Kappatos, Vassilios

    2017-01-01

    Purpose – This paper presents the development of an advanced structural assessment approach for aerospace components (metallic and composites). This work focuses on developing an automatic image processing methodology based on Non Destructive Testing (NDT) data and numerical models, for predicting...... the residual strength of these components. Design/methodology/approach – An image processing algorithm, based on the threshold method, has been developed to process and quantify the geometric characteristics of damages. Then, a parametric Finite Element (FE) model of the damaged component is developed based...... on the inputs acquired from the image processing algorithm. The analysis of the metallic structures is employing the Extended FE Method (XFEM), while for the composite structures the Cohesive Zone Model (CZM) technique with Progressive Damage Modelling (PDM) is used. Findings – The numerical analyses...

  13. Solid Waste Projection Model: Model user's guide

    International Nuclear Information System (INIS)

    Stiles, D.L.; Crow, V.L.

    1990-08-01

    The Solid Waste Projection Model (SWPM) system is an analytical tool developed by Pacific Northwest Laboratory (PNL) for Westinghouse Hanford company (WHC) specifically to address solid waste management issues at the Hanford Central Waste Complex (HCWC). This document, one of six documents supporting the SWPM system, contains a description of the system and instructions for preparing to use SWPM and operating Version 1 of the model. 4 figs., 1 tab

  14. Variational analysis and aerospace engineering mathematical challenges for the aerospace of the future

    CERN Document Server

    Mohammadi, Bijan; Pironneau, Olivier; Cipolla, Vittorio

    2016-01-01

    This book presents papers surrounding the extensive discussions that took place from the ‘Variational Analysis and Aerospace Engineering’ workshop held at the Ettore Majorana Foundation and Centre for Scientific Culture in 2015. Contributions to this volume focus on advanced mathematical methods in aerospace engineering and industrial engineering such as computational fluid dynamics methods, optimization methods in aerodynamics, optimum controls, dynamic systems, the theory of structures, space missions, flight mechanics, control theory, algebraic geometry for CAD applications, and variational methods and applications. Advanced graduate students, researchers, and professionals in mathematics and engineering will find this volume useful as it illustrates current collaborative research projects in applied mathematics and aerospace engineering.

  15. Computational Modeling of Flow Control Systems for Aerospace Vehicles, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Clear Science Corp. proposes to develop computational methods for designing active flow control systems on aerospace vehicles with the primary objective of...

  16. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report number 20: The use of selected information products and services by US aerospace engineers and scientists: Results of two surveys

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally, funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DoD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from two surveys of our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report and close with a brief overview of on-going research into aerospace knowledge diffusion focusing on the role of the industry-affiliated information intermediary.

  17. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 12: The diffusion of federally funded aerospace Research and Development (R&D) and the information seeking behavior of US aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.

    1991-01-01

    The present exploration of the diffusion of federally-funded R&D via the information-seeking behavior of scientists and engineers proceeds under three assumptions: (1) that knowledge transfer and utilization is as important as knowledge production; (2) that the diffusion of knowledge obtained through federally-funded R&D is necessary for the maintenance of U.S. preeminence in the aerospace field; and (3) that federally-funded NASA and DoD technical reports play an important, albeit as-yet undefined, role in aerospace R&D diffusion. A conceptual model is presented for the process of knowledge diffusion that stresses the role of U.S. government-funded technical reports.

  18. High-End Computing Challenges in Aerospace Design and Engineering

    Science.gov (United States)

    Bailey, F. Ronald

    2004-01-01

    High-End Computing (HEC) has had significant impact on aerospace design and engineering and is poised to make even more in the future. In this paper we describe four aerospace design and engineering challenges: Digital Flight, Launch Simulation, Rocket Fuel System and Digital Astronaut. The paper discusses modeling capabilities needed for each challenge and presents projections of future near and far-term HEC computing requirements. NASA's HEC Project Columbia is described and programming strategies presented that are necessary to achieve high real performance.

  19. Damage Characterization and Real-Time Health Monitoring of Aerospace Materials Using Innovative NDE Tools

    Science.gov (United States)

    Matikas, Theodore E.

    2010-07-01

    The objective of this work is to characterize the damage and monitor in real-time aging structural components used in aerospace applications by means of advanced nondestructive evaluation techniques. Two novel experimental methodologies are used in this study, based on ultrasonic microscopy and nonlinear acoustics. It is demonstrated in this work that ultrasonic microscopy can be successfully utilized for local elastic property measurement, crack-size determination as well as for interfacial damage evaluation in high-temperature materials, such as metal matrix composites. Nonlinear acoustics enables real-time monitoring of material degradation in aerospace structures. When a sinusoidal ultrasonic wave of a given frequency and of sufficient amplitude is introduced into a nonharmonic solid, the fundamental wave distorts as it propagates, and therefore the second and higher harmonics of the fundamental frequency are generated. Measurements of the amplitude of these harmonics provide information on the coefficient of second- and higher-order terms of the stress-strain relation for a nonlinear solid. It is shown in this article that the material bulk nonlinear parameter for metallic alloy samples at different fatigue levels exhibits large changes compared to linear ultrasonic parameters, such as velocity and attenuation.

  20. Aerospace materials and material technologies

    CERN Document Server

    Wanhill, R

    2017-01-01

    This book is a comprehensive compilation of chapters on materials (both established and evolving) and material technologies that are important for aerospace systems. It considers aerospace materials in three Parts. Part I covers Metallic Materials (Mg, Al, Al-Li, Ti, aero steels, Ni, intermetallics, bronzes and Nb alloys); Part II deals with Composites (GLARE, PMCs, CMCs and Carbon based CMCs); and Part III considers Special Materials. This compilation has ensured that no important aerospace material system is ignored. Emphasis is laid in each chapter on the underlying scientific principles as well as basic and fundamental mechanisms leading to processing, characterization, property evaluation and applications. A considerable amount of materials data is compiled and presented in appendices at the end of the book. This book will be useful to students, researchers and professionals working in the domain of aerospace materials.

  1. Research progress in mutational effects of aerospace on crop and ground simulation on aerospace environment factors

    International Nuclear Information System (INIS)

    Liu Luxiang; Wang Jing; Zhao Linshu; Guo Huijun; Zhao Shirong; Zheng Qicheng; Yang Juncheng

    2004-01-01

    In this paper, the current status of aerospace botany research in aboard was briefly introduced. The research progress of mutational effects of aerospace on crop seed and its application in germplasm enhancement and new variety development by using recoverable satellite techniques in China has been reviewed. The approaches and its experimental advances of ground simulation on aerospace environmental factors were analyzed at different angles of particle biology, physical field biology and gravity biology

  2. Aerogels in Aerospace: An Overview

    Directory of Open Access Journals (Sweden)

    Nadiir Bheekhun

    2013-01-01

    Full Text Available Aerogels are highly porous structures prepared via a sol-gel process and supercritical drying technology. Among the classes of aerogels, silica aerogel exhibits the most remarkable physical properties, possessing lower density, thermal conductivity, refractive index, and dielectric constant than any solids. Its acoustical property is such that it can absorb the sound waves reducing speed to 100 m/s compared to 332 m/s for air. However, when it comes to commercialization, the result is not as expected. It seems that mass production, particularly in the aerospace industry, has dawdled behind. This paper highlights the evolution of aerogels in general and discusses the functions and significances of silica aerogel in previous astronautical applications. Future outer-space applications have been proposed as per the current research trend. Finally, the implementation of conventional silica aerogel in aeronautics is argued with an alternative known as Maerogel.

  3. 44th Aerospace Mechanisms Symposium

    Science.gov (United States)

    Boesiger, Edward A. (Compiler)

    2018-01-01

    The Aerospace Mechanisms Symposium (AMS) provides a unique forum for those active in the design, production and use of aerospace mechanisms. A major focus is the reporting of problems and solutions associated with the development and flight certification of new mechanisms.

  4. NADA/DOD Aerospace Knowledge Diffusion Research Project. Report number 19: The US government technical report and the transfer of federally funded aerospace R/D: An analysis of five studies

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the 'NASA/DoD Aerospace Knowledge Diffusion Research Project'. In this report, we summarize the literature on technical reprts and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from five studies of our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report and close with a brief overview of on-going research into the use of the U.S. government technical report as a rhetorical device for transferring federally funded aerospace R&D.

  5. NASA/DoD Aerospace Knowledge Diffusion Research Project: Report 43: The Technical Communication Practices of U.S. Aerospace Engineers and Scientists: Results of the Phase 1 Mail Survey -- Manufacturing and Production Perspective

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1996-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis the technical communication practices of U.S. aerospace engineers and scientists who were members of the Society of Manufacturing Engineers.

  6. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 19: Computer and information technology and aerospace knowledge diffusion

    Science.gov (United States)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.; Bishop, Ann P.

    1992-01-01

    To remain a world leader in aerospace, the US must improve and maintain the professional competency of its engineers and scientists, increase the research and development (R&D) knowledge base, improve productivity, and maximize the integration of recent technological developments into the R&D process. How well these objectives are met, and at what cost, depends on a variety of factors, but largely on the ability of US aerospace engineers and scientists to acquire and process the results of federally funded R&D. The Federal Government's commitment to high speed computing and networking systems presupposes that computer and information technology will play a major role in the aerospace knowledge diffusion process. However, we know little about information technology needs, uses, and problems within the aerospace knowledge diffusion process. The use of computer and information technology by US aerospace engineers and scientists in academia, government, and industry is reported.

  7. 77 FR 64767 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Science.gov (United States)

    2012-10-23

    ... Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Airplanes AGENCY... airworthiness directive (AD) for certain Gulfstream Aerospace LP (Type Certificate previously held by Israel... Certificate previously held by Israel Aircraft Industries, Ltd.) Model Galaxy and Gulfstream 200 airplanes...

  8. 78 FR 47546 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Science.gov (United States)

    2013-08-06

    ... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Model... Aviation Authority of Israel (CAAI), which is the aviation authority for Israel, has issued Israeli...

  9. Smart antennas in aerospace applications

    NARCIS (Netherlands)

    Verpoorte, Jaco; Schippers, Harmen; Roeloffzen, C.G.H.; Marpaung, D.A.I.

    2010-01-01

    The interest in Smart Antennas for aerospace applications is growing. This paper describes smart antennas which can be used on aircraft. Two aerospace applications are discussed in more detail: a phased array antenna with optical beam forming and a large vibrating phased array antenna with

  10. Aerospace engineering training: universities experience

    Directory of Open Access Journals (Sweden)

    Mertins Kseniya

    2016-01-01

    Full Text Available Contemporary professional working in aerospace engineering must have a set of soft and hard skills. The experience gained in universities shows that training of a competent professional is impossible without an employer involved in this process. The paper provides an analysis of missions, tasks and experience of aerospace professionals and identifies the present and future roles, missions and required skills of a highly qualified specialist in aerospace engineering. This analysis can be used to design a master’s program aiming at providing students with the required knowledge, know-how and attitudes needed to succeed as professionals in industrial companies.

  11. Aeromedical solutions for aerospace safety.

    Science.gov (United States)

    Kapoor, Pawan; Gaur, Deepak

    2017-10-01

    All facets of activity in the speciality of Aviation Medicine are essentially aimed at enhancing aerospace safety. This paper highlights some innovative changes brought about by Aerospace Medicine in the three major fields of the speciality namely, medical evaluation, aeromedical training and research. Based on lab and field studies, military aircrew are now permitted flying with Modifinil as 'Go' Pill and Zolpidem as 'No-Go' Pill during sustained operations. Several other drugs for disabilities like Hypertension and CAD are now permitted for aviators. Comprehensive revision of policy permitting early return to flying is an on-going process. OPRAM courses for all three streams of aircrew in IAF have contributed to reduce aircraft accident rates. Human Engineering Consultancy and expert advice is provided by specialists at IAM as well as those in the field. In future, the country needs to provide better post-service opportunities to aerospace medicine specialists. This, in turn, will attract bright young minds to the specialty. The ISRO Humanin-Space programme will be an exciting challenge for all in this unique field. Aerospace Medicine continues to provide aerospace safety solutions to the IAF and the aviation industry. The nation needs to continue to utilize and support this specialty.

  12. Recent advances in the development of aerospace materials

    Science.gov (United States)

    Zhang, Xuesong; Chen, Yongjun; Hu, Junling

    2018-02-01

    In recent years, much progress has been made on the development of aerospace materials for structural and engine applications. Alloys, such as Al-based alloys, Mg-based alloys, Ti-based alloys, and Ni-based alloys, are developed for aerospace industry with outstanding advantages. Composite materials, the innovative materials, are taking more and more important roles in aircrafts. However, recent aerospace materials still face some major challenges, such as insufficient mechanical properties, fretting wear, stress corrosion cracking, and corrosion. Consequently, extensive studies have been conducted to develop the next generation aerospace materials with superior mechanical performance and corrosion resistance to achieve improvements in both performance and life cycle cost. This review focuses on the following topics: (1) materials requirements in design of aircraft structures and engines, (2) recent advances in the development of aerospace materials, (3) challenges faced by recent aerospace materials, and (4) future trends in aerospace materials.

  13. 32 CFR 705.30 - Aerospace Education Workshop.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Aerospace Education Workshop. 705.30 Section 705... REGULATIONS AND OFFICIAL RECORDS PUBLIC AFFAIRS REGULATIONS § 705.30 Aerospace Education Workshop. (a) This... of Naval Operations has cognizance of all assistance provided by the Navy to all Aerospace Education...

  14. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report No. 36: The Technical Communications Practices of US Aerospace Engineers and Scientists: Results of the Phase 1 NASA Langley Research Center Mail Survey

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1995-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis the technical communications practices of U.S. aerospace engineers and scientists who were assigned to the Research and Technology Group (RTG) at the NASA Langley Research Center in September 1995.

  15. Technical communications in aerospace - An analysis of the practices reported by U.S. and European aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.; Glassman, Myron

    1990-01-01

    The flow of scientific and technical information (STI) at the individual, organizational, national, and international levels is studied. The responses of U.S and European aerospace engineers and scientists to questionnaires concerning technical communications in aerospace are examined. Particular attention is given to the means used to communicate information and the social system of the aerospace knowledge diffusion process. Demographic data about the survey respondents are provided. The methods used to communicate technical data and the sources utilized to solve technical problems are described. The importance of technical writing skills and the use of computer technology in the aerospace field are discussed. The derived data are useful for R&D and information managers in order to improve access to and utilization of aerospace STI.

  16. Multiscale modelling and experimentation of hydrogen embrittlement in aerospace materials

    Science.gov (United States)

    Jothi, Sathiskumar

    to improve the resistance to hydrogen embrittlement in aerospace materials are also suggested. This knowledge can play an important role in the development of new hydrogen embrittlement resistant materials. A novel micro/macro-scale coupled finite element method incorporating multi-scale experimental data is presented with which it is possible to perform full scale component analyses in order to investigate hydrogen embrittlement at the design stage. Finally, some preliminary and very encouraging results of grain boundary engineering based techniques to develop alloys that are resistant to hydrogen induced failure are presented. Keywords: Hydrogen embrittlement; Aerospace materials; Ariane 5 combustion chamber; Pulse plated nickel; Nickel based super alloy 718; SSRT test; Weldability test; TDA; SEM/EBSD; Hydrogen induced hot and cold cracking; Multiscale modelling and experimental methods.

  17. 77 FR 44113 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Science.gov (United States)

    2012-07-27

    ... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Aerospace LP (Type Certificate previously held by Israel Aircraft Industries, Ltd.) Model Gulfstream G150... to the manufacturer. This action was prompted by a report from the Civil Aviation Authority of Israel...

  18. Aerospace Training. Washington's Community and Technical Colleges

    Science.gov (United States)

    Washington State Board for Community and Technical Colleges, 2014

    2014-01-01

    Aerospace is an economic powerhouse that generates jobs and fuels our economy. Washington's community and technical colleges produce the world-class employees needed to keep it that way. With about 1,250 aerospace-related firms employing more than 94,000 workers, Washington has the largest concentration of aerospace expertise in the nation. To…

  19. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 47: The value of computer networks in aerospace

    Science.gov (United States)

    Bishop, Ann Peterson; Pinelli, Thomas E.

    1995-01-01

    This paper presents data on the value of computer networks that were obtained from a national survey of 2000 aerospace engineers that was conducted in 1993. Survey respondents reported the extent to which they used computer networks in their work and communication and offered their assessments of the value of various network types and applications. They also provided information about the positive impacts of networks on their work, which presents another perspective on value. Finally, aerospace engineers' recommendations on network implementation present suggestions for increasing the value of computer networks within aerospace organizations.

  20. A Discrete Approach to Meshless Lagrangian Solid Modeling

    Directory of Open Access Journals (Sweden)

    Matthew Marko

    2017-07-01

    Full Text Available The author demonstrates a stable Lagrangian solid modeling method, tracking the interactions of solid mass particles rather than using a meshed grid. This numerical method avoids the problem of tensile instability often seen with smooth particle applied mechanics by having the solid particles apply stresses expected with Hooke’s law, as opposed to using a smoothing function for neighboring solid particles. This method has been tested successfully with a bar in tension, compression, and shear, as well as a disk compressed into a flat plate, and the numerical model consistently matched the analytical Hooke’s law as well as Hertz contact theory for all examples. The solid modeling numerical method was then built into a 2-D model of a pressure vessel, which was tested with liquid water particles under pressure and simulated with smoothed particle hydrodynamics. This simulation was stable, and demonstrated the feasibility of Lagrangian specification modeling for fluid–solid interactions.

  1. Liquid Nitrogen Removal of Critical Aerospace Materials

    Science.gov (United States)

    Noah, Donald E.; Merrick, Jason; Hayes, Paul W.

    2005-01-01

    Identification of innovative solutions to unique materials problems is an every-day quest for members of the aerospace community. Finding a technique that will minimize costs, maximize throughput, and generate quality results is always the target. United Space Alliance Materials Engineers recently conducted such a search in their drive to return the Space Shuttle fleet to operational status. The removal of high performance thermal coatings from solid rocket motors represents a formidable task during post flight disassembly on reusable expended hardware. The removal of these coatings from unfired motors increases the complexity and safety requirements while reducing the available facilities and approved processes. A temporary solution to this problem was identified, tested and approved during the Solid Rocket Booster (SRB) return to flight activities. Utilization of ultra high-pressure liquid nitrogen (LN2) to strip the protective coating from assembled space shuttle hardware marked the first such use of the technology in the aerospace industry. This process provides a configurable stream of liquid nitrogen (LN2) at pressures of up to 55,000 psig. The performance of a one-time certification for the removal of thermal ablatives from SRB hardware involved extensive testing to ensure adequate material removal without causing undesirable damage to the residual materials or aluminum substrates. Testing to establish appropriate process parameters such as flow, temperature and pressures of the liquid nitrogen stream provided an initial benchmark for process testing. Equipped with these initial parameters engineers were then able to establish more detailed test criteria that set the process limits. Quantifying the potential for aluminum hardware damage represented the greatest hurdle for satisfying engineers as to the safety of this process. Extensive testing for aluminum erosion, surface profiling, and substrate weight loss was performed. This successful project clearly

  2. 76 FR 62455 - Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2011-10-07

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (11-088)] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announces a forthcoming meeting of the Aerospace Safety Advisory Panel... Burch, Aerospace Safety Advisory Panel Administrative Officer, National Aeronautics and Space...

  3. 78 FR 1265 - Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2013-01-08

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice 13-001] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announces a forthcoming meeting of the Aerospace Safety Advisory Panel..., Aerospace Safety Advisory Panel Executive Director, National Aeronautics and Space Administration...

  4. 76 FR 19147 - Aerospace Safety Advisory Panel; Meeting.

    Science.gov (United States)

    2011-04-06

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (11-030)] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announce a forthcoming meeting of the Aerospace Safety Advisory Panel.... Kathy Dakon, Aerospace Safety Advisory Panel Executive Director, National Aeronautics and Space...

  5. 78 FR 56941 - Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2013-09-16

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice: 13-114] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announces a forthcoming meeting of the Aerospace Safety Advisory Panel.... Harmony Myers, Aerospace Safety Advisory Panel Executive Director, National Aeronautics and Space...

  6. 77 FR 25502 - Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2012-04-30

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (12-030)] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announce a forthcoming meeting of the Aerospace Safety Advisory Panel... FURTHER INFORMATION CONTACT: Ms. Harmony Myers, Aerospace Safety Advisory Panel Executive Director...

  7. 77 FR 38090 - Aerospace Safety Advisory Panel; Meeting.

    Science.gov (United States)

    2012-06-26

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice 12-044] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announces a forthcoming meeting of the Aerospace Safety Advisory Panel.... Harmony Myers, Aerospace Safety Advisory Panel Executive Director, National Aeronautics and Space...

  8. 75 FR 61219 - Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2010-10-04

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (10-116)] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announces a forthcoming meeting of the Aerospace Safety Advisory Panel... Dakon, Aerospace Safety Advisory Panel Executive Director, National Aeronautics and Space Administration...

  9. 77 FR 58413 - Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2012-09-20

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice 12-074] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announces a forthcoming meeting of the Aerospace Safety Advisory Panel.... Harmony Myers, Aerospace Safety Advisory Panel Executive Director, National Aeronautics and Space...

  10. Capital raising of aerospace companies: equities or debts?

    Science.gov (United States)

    Hui-Shan, L.; Taw-Onn, Y.; Wai-Mun, H.

    2016-10-01

    Aerospace products enhance national and economic activities, thus maintaining the sustainability of aerospace industry is crucial. One of the perspectives in ensuring sustainability of aerospace companies is expansion of firms by raising funds for research and development in order to provide a reasonable profitability to the firms. This study comprises a sample of 47 aerospace companies from 2009 to 2015 to analyze the impact of raising fund by equities or debts to the profitability of the firms. The result indicates that capital raising through equities is preferable than debts. Moreover, the study also identifies that the profit of aerospace industry is volatile and there is cyclical reduction of the net income in the first quarter of the year. The management needs to make wise decisions in raising fund to ensure a healthy growth of the aerospace company.

  11. Online Dectection and Modeling of Safety Boundaries for Aerospace Application Using Bayesian Statistics

    Science.gov (United States)

    He, Yuning

    2015-01-01

    The behavior of complex aerospace systems is governed by numerous parameters. For safety analysis it is important to understand how the system behaves with respect to these parameter values. In particular, understanding the boundaries between safe and unsafe regions is of major importance. In this paper, we describe a hierarchical Bayesian statistical modeling approach for the online detection and characterization of such boundaries. Our method for classification with active learning uses a particle filter-based model and a boundary-aware metric for best performance. From a library of candidate shapes incorporated with domain expert knowledge, the location and parameters of the boundaries are estimated using advanced Bayesian modeling techniques. The results of our boundary analysis are then provided in a form understandable by the domain expert. We illustrate our approach using a simulation model of a NASA neuro-adaptive flight control system, as well as a system for the detection of separation violations in the terminal airspace.

  12. Advances in control system technology for aerospace applications

    CERN Document Server

    2016-01-01

    This book is devoted to Control System Technology applied to aerospace and covers the four disciplines Cognitive Engineering, Computer Science, Operations Research, and Servo-Mechanisms. This edited book follows a workshop held at the Georgia Institute of Technology in June 2012, where the today's most important aerospace challenges, including aerospace autonomy, safety-critical embedded software engineering, and modern air transportation were discussed over the course of two days of intense interactions among leading aerospace engineers and scientists. Its content provide a snapshot of today's aerospace control research and its future, including Autonomy in space applications, Control in space applications, Autonomy in aeronautical applications, Air transportation, and Safety-critical software engineering.

  13. 75 FR 6407 - Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2010-02-09

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (10- 020)] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announce a forthcoming meeting of the Aerospace Safety Advisory Panel... FURTHER INFORMATION CONTACT: Ms. Kathy Dakon, Aerospace Safety Advisory Panel Executive Director, National...

  14. On the use of semiempirical models of (solid + supercritical fluid) systems to determine solid sublimation properties

    International Nuclear Information System (INIS)

    Tabernero, Antonio; Martin del Valle, Eva M.; Galan, Miguel A.

    2011-01-01

    Research highlights: → We propose a method to determine sublimation properties of solids. → Low deviations were produced calculating sublimation enthalpies and pressures. → It is a required step to determine the vaporization enthalpy of the solid. → It is possible to determine solid properties using semiempirical models solid-SCF. - Abstract: Experimental solubility data of solid-supercritical fluids have significantly increased in the last few years, and semiempirical models are emerging as one of the best choices to fit this type of data. This work establishes a methodology to calculate sublimation pressures using this type of equations. It requires the use of Bartle's equation to model equilibria data solid-supercritical fluids with the aim of determining the vaporization enthalpy of the compound. Using this method, low deviations were obtained by calculating sublimation pressures and sublimation enthalpies. The values of the sublimation pressures were subsequently used to successfully model different multiphasic equilibria, as solid-supercritical fluids and solid-solvent-supercritical fluids with the Peng-Robinson equation of state (without considering the sublimation pressure as an adjustable parameter). On the other hand, the sublimation pressures were also used to calculate solid sublimation properties and acetaminophen solvation properties in some solvents. Also, solubility data solid-supercritical fluids from 62 pharmaceuticals were fitted with different semiempirical equations (Chrastil, Kumar-Johnston and Bartle models) in order to present the values of solvation enthalpies in sc-CO 2 and vaporization enthalpies for these compounds. All of these results highlight that semiempirical models can be used for any other purpose as well as modeling (solid + supercritical fluids) equilibria.

  15. 78 FR 36793 - Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2013-06-19

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice 13-068] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announce a forthcoming meeting of the Aerospace Safety Advisory Panel..., Huntsville, AL 35805 FOR FURTHER INFORMATION CONTACT: Ms. Harmony Myers, Aerospace Safety Advisory Panel...

  16. 75 FR 36697 - Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2010-06-28

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (10-071)] Aerospace Safety Advisory Panel... Aeronautics and Space Administration announce a forthcoming meeting of the Aerospace Safety Advisory Panel..., Room 116, Hampton, VA 23681. FOR FURTHER INFORMATION CONTACT: Ms. Kathy Dakon, Aerospace Safety...

  17. Development of a Dynamically Configurable,Object-Oriented Framework for Distributed, Multi-modal Computational Aerospace Systems Simulation

    Science.gov (United States)

    Afjeh, Abdollah A.; Reed, John A.

    2003-01-01

    This research is aimed at developing a neiv and advanced simulation framework that will significantly improve the overall efficiency of aerospace systems design and development. This objective will be accomplished through an innovative integration of object-oriented and Web-based technologies ivith both new and proven simulation methodologies. The basic approach involves Ihree major areas of research: Aerospace system and component representation using a hierarchical object-oriented component model which enables the use of multimodels and enforces component interoperability. Collaborative software environment that streamlines the process of developing, sharing and integrating aerospace design and analysis models. . Development of a distributed infrastructure which enables Web-based exchange of models to simplify the collaborative design process, and to support computationally intensive aerospace design and analysis processes. Research for the first year dealt with the design of the basic architecture and supporting infrastructure, an initial implementation of that design, and a demonstration of its application to an example aircraft engine system simulation.

  18. Aerospace Engineering Systems

    Science.gov (United States)

    VanDalsem, William R.; Livingston, Mary E.; Melton, John E.; Torres, Francisco J.; Stremel, Paul M.

    1999-01-01

    Continuous improvement of aerospace product development processes is a driving requirement across much of the aerospace community. As up to 90% of the cost of an aerospace product is committed during the first 10% of the development cycle, there is a strong emphasis on capturing, creating, and communicating better information (both requirements and performance) early in the product development process. The community has responded by pursuing the development of computer-based systems designed to enhance the decision-making capabilities of product development individuals and teams. Recently, the historical foci on sharing the geometrical representation and on configuration management are being augmented: Physics-based analysis tools for filling the design space database; Distributed computational resources to reduce response time and cost; Web-based technologies to relieve machine-dependence; and Artificial intelligence technologies to accelerate processes and reduce process variability. Activities such as the Advanced Design Technologies Testbed (ADTT) project at NASA Ames Research Center study the strengths and weaknesses of the technologies supporting each of these trends, as well as the overall impact of the combination of these trends on a product development event. Lessons learned and recommendations for future activities will be reported.

  19. Supporting the industrialisation of aerospace technologies

    CSIR Research Space (South Africa)

    Botha, M

    2015-10-01

    Full Text Available rates do not offer a competitive advantage; an insufficient skills pipeline; loss of skills; and risk of exclusion from secondary markets, due to rising aerospace emerging market economies. The Aerospace Industry Support Initiative (AISI) is a Department...

  20. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 6: Aerospace knowledge diffusion in the academic community: A report of phase 3 activities of the NASA/DOD Aerospace Knowledge Diffusion Research Project

    Science.gov (United States)

    Pinelli, Thomas E.; Kennedy, John M.

    1990-01-01

    Descriptive and analytical data regarding the flow of aerospace-based scientific and technical information (STI) in the academic community are presented. An overview is provided of the Federal Aerospace Knowledge Diffusion Research Project, illustrating a five-year program on aerospace knowledge diffusion. Preliminary results are presented of the project's research concerning the information-seeking habits, practices, and attitudes of U.S. aerospace engineering and science students and faculty. The type and amount of education and training in the use of information sources are examined. The use and importance ascribed to various information products by U.S. aerospace faculty and students including computer and other information technology is assessed. An evaluation of NASA technical reports is presented and it is concluded that NASA technical reports are rated high in terms of quality and comprehensiveness, citing Engineering Index and IAA as the most frequently used materials by faculty and students.

  1. Powered Flight The Engineering of Aerospace Propulsion

    CERN Document Server

    Greatrix, David R

    2012-01-01

    Whilst most contemporary books in the aerospace propulsion field are dedicated primarily to gas turbine engines, there is often little or no coverage of other propulsion systems and devices such as propeller and helicopter rotors or detailed attention to rocket engines. By taking a wider viewpoint, Powered Flight - The Engineering of Aerospace Propulsion aims to provide a broader context, allowing observations and comparisons to be made across systems that are overlooked by focusing on a single aspect alone. The physics and history of aerospace propulsion are built on step-by-step, coupled with the development of an appreciation for the mathematics involved in the science and engineering of propulsion. Combining the author’s experience as a researcher, an industry professional and a lecturer in graduate and undergraduate aerospace engineering, Powered Flight - The Engineering of Aerospace Propulsion covers its subject matter both theoretically and with an awareness of the practicalities of the industry. To ...

  2. Advanced Ceramic Materials for Future Aerospace Applications

    Science.gov (United States)

    Misra, Ajay

    2015-01-01

    With growing trend toward higher temperature capabilities, lightweight, and multifunctionality, significant advances in ceramic matrix composites (CMCs) will be required for future aerospace applications. The presentation will provide an overview of material requirements for future aerospace missions, and the role of ceramics and CMCs in meeting those requirements. Aerospace applications will include gas turbine engines, aircraft structure, hypersonic and access to space vehicles, space power and propulsion, and space communication.

  3. CAD-based Monte Carlo automatic modeling method based on primitive solid

    International Nuclear Information System (INIS)

    Wang, Dong; Song, Jing; Yu, Shengpeng; Long, Pengcheng; Wang, Yongliang

    2016-01-01

    Highlights: • We develop a method which bi-convert between CAD model and primitive solid. • This method was improved from convert method between CAD model and half space. • This method was test by ITER model and validated the correctness and efficiency. • This method was integrated in SuperMC which could model for SuperMC and Geant4. - Abstract: Monte Carlo method has been widely used in nuclear design and analysis, where geometries are described with primitive solids. However, it is time consuming and error prone to describe a primitive solid geometry, especially for a complicated model. To reuse the abundant existed CAD models and conveniently model with CAD modeling tools, an automatic modeling method for accurate prompt modeling between CAD model and primitive solid is needed. An automatic modeling method for Monte Carlo geometry described by primitive solid was developed which could bi-convert between CAD model and Monte Carlo geometry represented by primitive solids. While converting from CAD model to primitive solid model, the CAD model was decomposed into several convex solid sets, and then corresponding primitive solids were generated and exported. While converting from primitive solid model to the CAD model, the basic primitive solids were created and related operation was done. This method was integrated in the SuperMC and was benchmarked with ITER benchmark model. The correctness and efficiency of this method were demonstrated.

  4. Commercialization of terrestrial applications of aerospace power technology

    International Nuclear Information System (INIS)

    Landsberg, D.R.

    1992-01-01

    The potential for commercialization of terrestrial energy systems based upon aerospace power technology's explored. Threats to the aerospace power technology industry, caused by the end of the cold war and weak world economy are described. There are also new opportunities caused by increasing terrestrial energy needs and world-wide concern for the environment. In this paper, the strengths and weaknesses of the aerospace power industry in commercializing terrestrial energy technologies are reviewed. Finally, actions which will enable the aerospace power technology industry to commercialize products into terrestrial energy markets are described

  5. High Flight. Aerospace Activities, K-12.

    Science.gov (United States)

    Oklahoma State Dept. of Education, Oklahoma City.

    Following discussions of Oklahoma aerospace history and the history of flight, interdisciplinary aerospace activities are presented. Each activity includes title, concept fostered, purpose, list of materials needed, and procedure(s). Topics include planets, the solar system, rockets, airplanes, air travel, space exploration, principles of flight,…

  6. A solid-on-solid invasion percolation model for self-affine interfaces

    International Nuclear Information System (INIS)

    Arizmendi, C.M.; Martin, H.O.; Sanchez, J.R.

    1993-08-01

    The scaling properties of the interface of a new growth model are studied. The model is based on the standard invasion percolation without trapping in which the solid-on-solid condition is imposed. The local correlation between points of the interface can be controlled through a parameter. The self-affine properties of the interface show strong dependence on the existence of the local correlation. The dependence of the relevant exponents of the interface with the correlation is analysed. (author). 8 refs, 4 figs

  7. Extensions to the Dynamic Aerospace Vehicle Exchange Markup Language

    Science.gov (United States)

    Brian, Geoffrey J.; Jackson, E. Bruce

    2011-01-01

    The Dynamic Aerospace Vehicle Exchange Markup Language (DAVE-ML) is a syntactical language for exchanging flight vehicle dynamic model data. It provides a framework for encoding entire flight vehicle dynamic model data packages for exchange and/or long-term archiving. Version 2.0.1 of DAVE-ML provides much of the functionality envisioned for exchanging aerospace vehicle data; however, it is limited in only supporting scalar time-independent data. Additional functionality is required to support vector and matrix data, abstracting sub-system models, detailing dynamics system models (both discrete and continuous), and defining a dynamic data format (such as time sequenced data) for validation of dynamics system models and vehicle simulation packages. Extensions to DAVE-ML have been proposed to manage data as vectors and n-dimensional matrices, and record dynamic data in a compatible form. These capabilities will improve the clarity of data being exchanged, simplify the naming of parameters, and permit static and dynamic data to be stored using a common syntax within a single file; thereby enhancing the framework provided by DAVE-ML for exchanging entire flight vehicle dynamic simulation models.

  8. NASA-UVa light aerospace alloy and structures technology program

    Science.gov (United States)

    Gangloff, Richard P.; Haviland, John K.; Herakovich, Carl T.; Pilkey, Walter D.; Pindera, Marek-Jerzy; Scully, John R.; Stoner, Glenn E.; Swanson, Robert E.; Thornton, Earl A.; Wawner, Franklin E., Jr.

    1991-01-01

    The general objective of the NASA-UVa Light Aerospace Alloy and Structures Technology Program was to conduct research on the performance of next generation, light weight aerospace alloys, composites, and associated thermal gradient structures. The following research areas were actively investigated: (1) mechanical and environmental degradation mechanisms in advanced light metals and composites; (2) aerospace materials science; (3) mechanics of materials and composites for aerospace structures; and (4) thermal gradient structures.

  9. Mathematical modeling of ethanol production in solid-state fermentation based on solid medium' dry weight variation.

    Science.gov (United States)

    Mazaheri, Davood; Shojaosadati, Seyed Abbas; Zamir, Seyed Morteza; Mousavi, Seyyed Mohammad

    2018-04-21

    In this work, mathematical modeling of ethanol production in solid-state fermentation (SSF) has been done based on the variation in the dry weight of solid medium. This method was previously used for mathematical modeling of enzyme production; however, the model should be modified to predict the production of a volatile compound like ethanol. The experimental results of bioethanol production from the mixture of carob pods and wheat bran by Zymomonas mobilis in SSF were used for the model validation. Exponential and logistic kinetic models were used for modeling the growth of microorganism. In both cases, the model predictions matched well with the experimental results during the exponential growth phase, indicating the good ability of solid medium weight variation method for modeling a volatile product formation in solid-state fermentation. In addition, using logistic model, better predictions were obtained.

  10. Laser beam micro-milling of micro-channels in aerospace alloys

    CERN Document Server

    Ahmed, Naveed; Al-Ahmari, Abdulrahman

    2017-01-01

    This volume is greatly helpful to micro-machining and laser engineers as it offers obliging guidelines about the micro-channel fabrications through Nd:YAG laser beam micro-milling. The book also demonstrates how the laser beam micro-milling behaves when operating under wet conditions (under water), and explores what are the pros and cons of this hybrid technique. From the predictive mathematical models, the readers can easily estimate the resulting micro-channel size against the desired laser parametric combinations. The book considers micro-channels in three highly important research materials commonly used in aerospace industry: titanium alloy Ti-6Al-4V, nickel alloy Inconel 718 and aluminum alloy AA 2024. Therefore, the book is highly practicable in the fields of micro-channel heat exchangers, micro-channel aerospace turbine blades, micro-channel heat pipes, micro-coolers and micro-channel pulsating heat plates. These are frequently used in various industries such as aerospace, automotive, biomedical and m...

  11. NASA/DoD aerospace knowledge diffusion research project. VIII - The role of the information intermediary in the diffusion of aerospace knowledge

    Science.gov (United States)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.

    1990-01-01

    The U.S. aerospace industry is experiencing profound changes created by a combination of domestic actions and circumstances such as airline deregulation. Other changes result from external trends such as emerging foreign competition. These circumstances intensify the need to understand the production, transfer, and utilization of knowledge as a precursor to the rapid diffusion of technology. This article presents a conceptual framework for understanding the diffusion of aerospace knowledge. The framework focuses on the information channels and members of the social system associated with the aerospace knowledge diffusion process, placing particular emphasis on aerospace librarians as information intermediaries.

  12. A Local Composition Model for Paraffinic Solid Solutions

    DEFF Research Database (Denmark)

    Coutinho, A.P. João; Knudsen, Kim; Andersen, Simon Ivar

    1996-01-01

    The description of the solid-phase non-ideality remains the main obstacle in modelling the solid-liquid equilibrium of hydrocarbons. A theoretical model, based on the local composition concept, is developed for the orthorhombic phase of n-alkanes and tested against experimental data for binary sy...... systems. It is shown that it can adequately predict the experimental phase behaviour of paraffinic mixtures. This work extends the applicability of local composition models to the solid phase. Copyright (C) 1996 Elsevier Science Ltd....

  13. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 26: The relationship between technology policy and scientific and technical information within the US and Japanese aerospace industries

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1993-01-01

    Government technology policy has nurtured the growth of the aerospace industry which is vital to both the U.S. and Japanese economies. Japanese technology policy differs significantly from U.S. technology policy, however, particularly with respect to the production, transfer, and use of scientific and technical information (STI). In this paper, we discuss the unique position of the aerospace industry in the U.S. and Japan, U.S. and Japanese aerospace policy, and the role of STI in the process of aerospace innovation. The information-seeking behaviors of U.S. and Japanese aerospace engineers and scientists are compared. The authors advocate the development of innovation-adoption technology and STI policy goals for U.S. aerospace and the inclusion of an aerospace knowledge diffusion transfer system with an 'active' component for scanning and acquiring foreign aerospace technology and STI.

  14. Nanotechnology research for aerospace applications

    Science.gov (United States)

    Agee, Forrest J.; Lozano, Karen; Gutierrez, Jose M.; Chipara, Mircea; Thapa, Ram; Chow, Alice

    2009-04-01

    Nanotechnology is impacting the future of the military and aerospace. The increasing demands for high performance and property-specific applications are forcing the scientific world to take novel approaches in developing programs and accelerating output. CONTACT or Consortium for Nanomaterials for Aerospace Commerce and Technology is a cooperative nanotechnology research program in Texas building on an infrastructure that promotes collaboration between universities and transitioning to industry. The participants of the program include the US Air Force Research Laboratory (AFRL), five campuses of the University of Texas (Brownsville, Pan American, Arlington, Austin, and Dallas), the University of Houston, and Rice University. Through the various partnerships between the intellectual centers and the interactions with AFRL and CONTACT's industrial associates, the program represents a model that addresses the needs of the changing and competitive technological world. Into the second year, CONTACT has expanded to twelve projects that cover four areas of research: Adaptive Coatings and Surface Engineering, Nano Energetics, Electromagnetic Sensors, and Power Generation and Storage. This paper provides an overview of the CONTACT program and its projects including the research and development of new electrorheological fluids with nanoladen suspensions and composites and the potential applications.

  15. Modelling dewatering behaviour through an understanding of solids formation processes. Part II--solids separation considerations.

    Science.gov (United States)

    Dustan, A C; Cohen, B; Petrie, J G

    2005-05-30

    An understanding of the mechanisms which control solids formation can provide information on the characteristics of the solids which are formed. The nature of the solids formed in turn impacts on dewatering behaviour. The 'upstream' solids formation determines a set of suspension characteristics: solids concentration, particle size distribution, solution ionic strength and electrostatic surface potential. These characteristics together define the suspension's rheological properties. However, the complicated interdependence of these has precluded the prediction of suspension rheology from such a fundamental description of suspension characteristics. Recent shear yield stress models, applied in this study to compressive yield, significantly reduce the empiricism required for the description of compressive rheology. Suspension compressibility and permeability uniquely define the dewatering behaviour, described in terms of settling, filtration and mechanical expression. These modes of dewatering may be described in terms of the same fundamental suspension mechanics model. In this way, it is possible to link dynamically the processes of solids formation and dewatering of the resultant suspension. This, ultimately, opens the door to improved operability of these processes. In part I of this paper we introduced an integrated system model for solids formation and dewatering. This model was demonstrated for the upstream processes using experimental data. In this current paper models of colloidal interactions and dewatering are presented and compared to experimental results from batch filtration tests. A novel approach to predicting suspension compressibility and permeability using a single test configuration is presented and tested.

  16. iSTEM: The Aerospace Engineering Challenge

    Science.gov (United States)

    English, Lyn D.; King, Donna T.; Hudson, Peter; Dawes, Les

    2014-01-01

    The authors developed The Paper Plane Challenge as one of a three-part response to The Aerospace Engineering Challenge. The Aerospace Engineering Challenge was the second of three multi-part activities that they had developed with the teachers during the year. Their aim was to introduce students to the exciting world of engineering, where they…

  17. A visual LISP program for voxelizing AutoCAD solid models

    Science.gov (United States)

    Marschallinger, Robert; Jandrisevits, Carmen; Zobl, Fritz

    2015-01-01

    AutoCAD solid models are increasingly recognized in geological and geotechnical 3D modeling. In order to bridge the currently existing gap between AutoCAD solid models and the grid modeling realm, a Visual LISP program is presented that converts AutoCAD solid models into voxel arrays. Acad2Vox voxelizer works on a 3D-model that is made up of arbitrary non-overlapping 3D-solids. After definition of the target voxel array geometry, 3D-solids are scanned at grid positions and properties are streamed to an ASCII output file. Acad2Vox has a novel voxelization strategy that combines a hierarchical reduction of sampling dimensionality with an innovative use of AutoCAD-specific methods for a fast and memory-saving operation. Acad2Vox provides georeferenced, voxelized analogs of 3D design data that can act as regions-of-interest in later geostatistical modeling and simulation. The Supplement includes sample geological solid models with instructions for practical work with Acad2Vox.

  18. Mathematical modelling in solid mechanics

    CERN Document Server

    Sofonea, Mircea; Steigmann, David

    2017-01-01

    This book presents new research results in multidisciplinary fields of mathematical and numerical modelling in mechanics. The chapters treat the topics: mathematical modelling in solid, fluid and contact mechanics nonconvex variational analysis with emphasis to nonlinear solid and structural mechanics numerical modelling of problems with non-smooth constitutive laws, approximation of variational and hemivariational inequalities, numerical analysis of discrete schemes, numerical methods and the corresponding algorithms, applications to mechanical engineering numerical aspects of non-smooth mechanics, with emphasis on developing accurate and reliable computational tools mechanics of fibre-reinforced materials behaviour of elasto-plastic materials accounting for the microstructural defects definition of structural defects based on the differential geometry concepts or on the atomistic basis interaction between phase transformation and dislocations at nano-scale energetic arguments bifurcation and post-buckling a...

  19. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 28: The technical communication practices of Russian and US aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Keene, Michael L.; Flammia, Madelyn; Kennedy, John M.

    1993-01-01

    As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communication practices of Russian and U.S. aerospace engineers and scientists. Both studies had the same five objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communication to their professions; second, to determine the use and production of technical communication by aerospace engineers and scientists; third, to seek their views about the appropriate content of the undergraduate course in technical communication; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line databases; and fifth, to determine the use and importance of computer and information technology to them. A self administered questionnaire was distributed to Russian aerospace engineers and scientists at the Central Aero-Hydrodynamic Institute (TsAGI) and to their U.S. counterparts at the NASA Ames Research Center and the NASA Langley Research Center. The completion rates for the Russian and U.S. surveys were 64 and 61 percent, respectively. Responses of the Russian and U.S. participants to selected questions are presented in this paper.

  20. ScienceScope: Aerospace

    CSIR Research Space (South Africa)

    CSIR

    2006-12-01

    Full Text Available In this edition of ScienceScope, innovations in and around aerodynamics research and development is explored. The publication explores activities in environmentally friendly aerospace technologies to enhance the aviation industry....

  1. 78 FR 57903 - Aerospace Safety Advisory Panel; Charter Renewal

    Science.gov (United States)

    2013-09-20

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice: 13-116] Aerospace Safety Advisory Panel... and amendment of the charter of the Aerospace Safety Advisory Panel. SUMMARY: Pursuant to sections 14... determined that renewal and amendment of the charter of the Aerospace Safety Advisory Panel is in the public...

  2. 76 FR 65750 - Aerospace Safety Advisory Panel; Charter Renewal

    Science.gov (United States)

    2011-10-24

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (11-105)] Aerospace Safety Advisory Panel... and amendment of the charter of the NASA Aerospace Safety Advisory Panel. SUMMARY: Pursuant to... determined that a renewal and amendment of the charter of the NASA Aerospace Safety Advisory Panel is in the...

  3. A Model-Based Approach to Engineering Behavior of Complex Aerospace Systems

    Science.gov (United States)

    Ingham, Michel; Day, John; Donahue, Kenneth; Kadesch, Alex; Kennedy, Andrew; Khan, Mohammed Omair; Post, Ethan; Standley, Shaun

    2012-01-01

    One of the most challenging yet poorly defined aspects of engineering a complex aerospace system is behavior engineering, including definition, specification, design, implementation, and verification and validation of the system's behaviors. This is especially true for behaviors of highly autonomous and intelligent systems. Behavior engineering is more of an art than a science. As a process it is generally ad-hoc, poorly specified, and inconsistently applied from one project to the next. It uses largely informal representations, and results in system behavior being documented in a wide variety of disparate documents. To address this problem, JPL has undertaken a pilot project to apply its institutional capabilities in Model-Based Systems Engineering to the challenge of specifying complex spacecraft system behavior. This paper describes the results of the work in progress on this project. In particular, we discuss our approach to modeling spacecraft behavior including 1) requirements and design flowdown from system-level to subsystem-level, 2) patterns for behavior decomposition, 3) allocation of behaviors to physical elements in the system, and 4) patterns for capturing V&V activities associated with behavioral requirements. We provide examples of interesting behavior specification patterns, and discuss findings from the pilot project.

  4. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 8: The role of the information intermediary in the diffusion of aerospace knowledge

    Science.gov (United States)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.

    1990-01-01

    The United States aerospace industry is experiencing profound changes created by a combination of domestic actions and circumstances such as airline deregulation. Other changes result from external trends such as emerging foreign competition. These circumstances intensify the need to understand the production, transfer, and utilization of knowledge as a precursor to the rapid diffusion of technology. Presented here is a conceptual framework for understanding the diffusion of technology. A conceptual framework is given for understanding the diffusion of aerospace knowledge. The framework focuses on the information channels and members of the social system associated with the aerospace knowledge diffusion process, placing particular emphasis on aerospace librarians as information intermediaries.

  5. Adaptive Modeling, Engineering Analysis and Design of Advanced Aerospace Vehicles

    Science.gov (United States)

    Mukhopadhyay, Vivek; Hsu, Su-Yuen; Mason, Brian H.; Hicks, Mike D.; Jones, William T.; Sleight, David W.; Chun, Julio; Spangler, Jan L.; Kamhawi, Hilmi; Dahl, Jorgen L.

    2006-01-01

    This paper describes initial progress towards the development and enhancement of a set of software tools for rapid adaptive modeling, and conceptual design of advanced aerospace vehicle concepts. With demanding structural and aerodynamic performance requirements, these high fidelity geometry based modeling tools are essential for rapid and accurate engineering analysis at the early concept development stage. This adaptive modeling tool was used for generating vehicle parametric geometry, outer mold line and detailed internal structural layout of wing, fuselage, skin, spars, ribs, control surfaces, frames, bulkheads, floors, etc., that facilitated rapid finite element analysis, sizing study and weight optimization. The high quality outer mold line enabled rapid aerodynamic analysis in order to provide reliable design data at critical flight conditions. Example application for structural design of a conventional aircraft and a high altitude long endurance vehicle configuration are presented. This work was performed under the Conceptual Design Shop sub-project within the Efficient Aerodynamic Shape and Integration project, under the former Vehicle Systems Program. The project objective was to design and assess unconventional atmospheric vehicle concepts efficiently and confidently. The implementation may also dramatically facilitate physics-based systems analysis for the NASA Fundamental Aeronautics Mission. In addition to providing technology for design and development of unconventional aircraft, the techniques for generation of accurate geometry and internal sub-structure and the automated interface with the high fidelity analysis codes could also be applied towards the design of vehicles for the NASA Exploration and Space Science Mission projects.

  6. Selected aspects of the supply chain management in the aerospace industry

    Directory of Open Access Journals (Sweden)

    Ivan KOBLEN

    2013-03-01

    Full Text Available The paper in the introductory part underlines some factors concerning the aerospace supply chain management (SCM issue. Authors inform on selected definitions in this topic, levels of supply chain and its maturity. The authors are focusing on introducing of the explanation of main specifics of SCM in aerospace industry (original equipment manufacturer, processes and requirements for the suppliers selection and subsequently inform on the role and mission of selected international organizations involved in aerospace SCM and quality issues, namely The Aerospace and Defence Industries Association of Europe (ASD, International Aerospace Quality Group (IAQG and European Aerospace Quality Group (EAQG. The information on Quality Management System in the framework of aerospace industry and SCM are also introduced. The part of paper is dealing with information systems useful in the SCM (the Digital Product Chain and Enterprise Resource Planning. The last part of paper is focused on issue concerning the success factors for SCM in the aerospace industry. In the conclusion part the authors emphasize some aspects and factors regarding the aerospace SCM and summarize the key challenges in the area of SCM in the aerospace industry.

  7. Wax Precipitation Modeled with Many Mixed Solid Phases

    DEFF Research Database (Denmark)

    Heidemann, Robert A.; Madsen, Jesper; Stenby, Erling Halfdan

    2005-01-01

    The behavior of the Coutinho UNIQUAC model for solid wax phases has been examined. The model can produce as many mixed solid phases as the number of waxy components. In binary mixtures, the solid rich in the lighter component contains little of the heavier component but the second phase shows sub......-temperature and low-temperature forms, are pure. Model calculations compare well with the data of Pauly et al. for C18 to C30 waxes precipitating from n-decane solutions. (C) 2004 American Institute of Chemical Engineers....

  8. Radial restricted solid-on-solid and etching interface-growth models

    Science.gov (United States)

    Alves, Sidiney G.

    2018-03-01

    An approach to generate radial interfaces is presented. A radial network recursively obtained is used to implement discrete model rules designed originally for the investigation in flat substrates. I used the restricted solid-on-solid and etching models as to test the proposed scheme. The results indicate the Kardar, Parisi, and Zhang conjecture is completely verified leading to a good agreement between the interface radius fluctuation distribution and the Gaussian unitary ensemble. The evolution of the radius agrees well with the generalized conjecture, and the two-point correlation function exhibits also a good agreement with the covariance of the Airy2 process. The approach can be used to investigate radial interfaces evolution for many other classes of universality.

  9. NASA/DoD Aerospace Knowledge Diffusion Research Project. XXVI - The relationship between technology policy and scientific and technical information within the U.S. and Japanese aerospace industries

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Lahr, Tom; Hoetker, Glenn

    1993-01-01

    Government technology policy has nurtured the growth of the aerospace industry, which is vital to both the U.S. and Japanese economies. Japanese technology policy differs significantly from U.S. technology policy, however, particularly with respect to the production, transfer, and use of scientific and technical information (STI). In this paper, we discuss the unique position of the aerospace industry in the U.S. and Japan, U.S. and Japanese aerospace policy, and the role of STI in the process of aerospace innovation. The information-seeking behaviors of U.S. and Japanese aerospace engineers and scientists are compared. The authors advocate the development of innovation-adoption technology and STI policy goals for U.S. aerospace and the inclusion of an aerospace knowledge diffusion transfer system with an 'active' component for scanning and acquiring foreign aerospace technology and STI.

  10. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 11: The Voice of the User: How US Aerospace Engineers and Scientists View DoD Technical Reports

    Science.gov (United States)

    Pinelli, Thomas E.; Kennedy, John M.

    1991-01-01

    The project examines how the results of NASA/DOD research diffuse into the aerospace R&D process, and empirically analyzes the implications of the aerospace knowledge diffusion process. Specific issues considered are the roles played by government technical reports, the recognition of the value of scientific and technical information (STI), and the optimization of the STI aerospace transfer system. Information-seeking habits are assessed for the U.S. aerospace community, the general community, the academic sector, and the international community. U.S. aerospace engineers and scientists use 65 percent of working time to communicate STI, and prefer 'internal' STI over 'external' STI. The isolation from 'external' information is found to be detrimental to U.S. aerospace R&D in general.

  11. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 14: Engineering work and information use in aerospace: Results of a telephone survey

    Science.gov (United States)

    Pinelli, Thomas E.; Kennedy, John M.; White, Terry F.

    1992-01-01

    A telephone survey of U.S. aerospace engineers and scientists who were on the Society of Automotive Engineers (SAE) mailing list was conducted between August 14-26, 1991. The survey was undertaken to obtain information on the daily work activities of aerospace engineers and scientists, to measure various practices used by aerospace engineers and scientists to obtain STI, and to ask aerospace engineers and scientists about their use of electronic networks. Co-workers were found important sources of information. Co-workers are used to obtain technical information because the information they have is relevant, not because co-workers are accessible. As technical uncertainty increases, so does the need for information internal and external to the organization. Electronic networks enjoy widespread use within the aerospace community. These networks are accessible and they are used to contact people at remote sites. About 80 percent of the respondents used electronic mail, file transfer, and information or data retrieval to commercial or in-house data bases.

  12. 77 FR 74579 - Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes

    Science.gov (United States)

    2012-12-17

    ... Certification Office (ACO), 1701 Columbia Avenue, College Park, Georgia 30337; phone: 404-474-5566; fax: 404-474... Management Branch, ACE-102A, FAA, Atlanta Aircraft Certification Office (ACO), 1701 Columbia Avenue, College... directive (AD) for certain Gulfstream Aerospace Corporation Model GIV-X airplanes. This AD requires...

  13. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 14: An analysis of the technical communications practices reported by Israeli and US aerospace engineers and scientists

    Science.gov (United States)

    Barclay, Rebecca O.; Pinelli, Thomas E.; Elazar, David; Kennedy, John M.

    1991-01-01

    As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two pilot studies were conducted that investigated the technical communications practices of Israeli and U.S. aerospace engineers and scientists. Both studies had the same five objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communications to their profession; second, to determine the use and production of technical communications by aerospace engineers and scientists; third, to seek their view about the appropriate content of an undergraduate course in technical communications; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line databases; and fifth, to determine the use and importance of computer and information technology to them. A self-administered questionnaire was mailed to randomly selected U.S. aerospace engineers and scientists who are working in cryogenics, adaptive walls, and magnetic suspension. A slightly modified version was sent to Israeli aerospace engineers and scientists working at Israel Aircraft Industries, LTD. Responses of the Israeli and U.S. aerospace engineers and scientists to selected questions are presented in this paper.

  14. Wireless Sensing Opportunities for Aerospace Applications

    Directory of Open Access Journals (Sweden)

    William Wilson

    2008-07-01

    Full Text Available Wireless sensors and sensor networks is an emerging technology area with many applications within the aerospace industry. Integrated vehicle health monitoring (IVHM of aerospace vehicles is needed to ensure the safety of the crew and the vehicle, yet often high costs, weight, size and other constraints prevent the incorporation of instrumentation onto spacecraft. This paper presents a few of the areas such as IVHM, where new wireless sensing technology is needed on both existing vehicles as well as future spacecraft. From ground tests to inflatable structures to the International Space Station, many applications could receive benefits from small, low power, wireless sensors. This paper also highlights some of the challenges that need to overcome when implementing wireless sensor networks for aerospace vehicles.

  15. Aerospace Environmental Technology Conference

    Science.gov (United States)

    Whitaker, A. F. (Editor)

    1995-01-01

    The mandated elimination of CFC's, Halons, TCA, and other ozone depleting chemicals and specific hazardous materials has required changes and new developments in aerospace materials and processes. The aerospace industry has been involved for several years in providing product substitutions, redesigning entire production processes, and developing new materials that minimize or eliminate damage to the environment. These activities emphasize replacement cleaning solvents and their application verifications, compliant coatings including corrosion protection systems, and removal techniques, chemical propulsion effects on the environment, and the initiation of modifications to relevant processing and manufacturing specifications and standards. The Executive Summary of this Conference is published as NASA CP-3297.

  16. Predicting Production Costs for Advanced Aerospace Vehicles

    Science.gov (United States)

    Bao, Han P.; Samareh, J. A.; Weston, R. P.

    2002-01-01

    For early design concepts, the conventional approach to cost is normally some kind of parametric weight-based cost model. There is now ample evidence that this approach can be misleading and inaccurate. By the nature of its development, a parametric cost model requires historical data and is valid only if the new design is analogous to those for which the model was derived. Advanced aerospace vehicles have no historical production data and are nowhere near the vehicles of the past. Using an existing weight-based cost model would only lead to errors and distortions of the true production cost. This paper outlines the development of a process-based cost model in which the physical elements of the vehicle are soared according to a first-order dynamics model. This theoretical cost model, first advocated by early work at MIT, has been expanded to cover the basic structures of an advanced aerospace vehicle. Elemental costs based on the geometry of the design can be summed up to provide an overall estimation of the total production cost for a design configuration. This capability to directly link any design configuration to realistic cost estimation is a key requirement for high payoff MDO problems. Another important consideration in this paper is the handling of part or product complexity. Here the concept of cost modulus is introduced to take into account variability due to different materials, sizes, shapes, precision of fabrication, and equipment requirements. The most important implication of the development of the proposed process-based cost model is that different design configurations can now be quickly related to their cost estimates in a seamless calculation process easily implemented on any spreadsheet tool.

  17. Index of International Publications in Aerospace Medicine

    Science.gov (United States)

    2010-10-01

    Aerospace Medicine technical reports are available in full-text from the Civil Aerospace Medical Institute’s publications Web site: www.faa.gov/library...System in Space and Other Extreme Conditions. England – USA: Harwood Academic Publishers, 1991. Konstantinova IV, Petrov RV. Sistema Immuniteta v

  18. Wind Turbine Aerodynamics from an Aerospace Perspective

    NARCIS (Netherlands)

    van Garrel, Arne; ten Pas, Sebastiaan; Venner, Cornelis H.; van Muijden, Jaap

    2018-01-01

    The current challenges in wind turbine aerodynamics simulations share a number of similarities with the challenges that the aerospace industry has faced in the past. Some of the current challenges in the aerospace aerodynamics community are also relevant for today’s wind turbine aerodynamics

  19. Online reinforcement learning control for aerospace systems

    NARCIS (Netherlands)

    Zhou, Y.

    2018-01-01

    Reinforcement Learning (RL) methods are relatively new in the field of aerospace guidance, navigation, and control. This dissertation aims to exploit RL methods to improve the autonomy and online learning of aerospace systems with respect to the a priori unknown system and environment, dynamical

  20. Development of three dimensional solid modeler

    International Nuclear Information System (INIS)

    Zahoor, R.M.A.

    1999-01-01

    The work presented in this thesis is aimed at developing a three dimensional solid modeler employing computer graphics techniques using C-Language. Primitives have been generated, by combination of plane surfaces, for various basic geometrical shapes including cylinder, cube and cone. Back face removal technique for hidden surface removal has also been incorporated. Various transformation techniques such as scaling, translation, and rotation have been included for the object animation. Three dimensional solid modeler has been created by the union of two primitives to demonstrate the capabilities of the developed program. (author)

  1. Engineering in the 21st century. [aerospace technology prospects

    Science.gov (United States)

    Mccarthy, J. F., Jr.

    1978-01-01

    A description is presented of the nature of the aerospace technology system that might be expected by the 21st century from a reasonable evolution of the current resources and capabilities. An aerospace employment outlook is provided. The years 1977 and 1978 seem to be marking the beginning of a period of stability and moderate growth in the aerospace industry. Aerospace research and development employment increased to 70,000 in 1977 and is now occupying a near-constant 18% share of the total research and development work force. The changing job environment is considered along with the future of aerospace education. It is found that one trend is toward a more interdisciplinary education. Most trend setters in engineering education recognize that the really challenging engineering problems invariably require the judicious exercise of several disciplines for their solution. Some future trends in aerospace technology are discussed. By the year 2000 space technology will have achieved major advances in four areas, including management of information, transportation, space structures, and energy.

  2. Nanotechnology in Aerospace Applications

    National Research Council Canada - National Science Library

    Meyyappan, M

    2007-01-01

    The aerospace applications for nanotechnology include high strength, low weight composites, improved electronics and displays with low power consumption, variety of physical sensors, multifunctional...

  3. Challenges in aerospace medicine education.

    Science.gov (United States)

    Grenon, S Marlene; Saary, Joan

    2011-11-01

    Aerospace medicine training and research represents a dream for many and a challenge for most. In Canada, although some opportunities exist for the pursuit of education and research in the aerospace medicine field, they are limited despite the importance of this field for enabling safe human space exploration. In this commentary, we aim to identify some of the challenges facing individuals wishing to get involved in the field as well as the causal factors for these challenges. We also explore strategies to mitigate against these.

  4. Probability and Statistics in Aerospace Engineering

    Science.gov (United States)

    Rheinfurth, M. H.; Howell, L. W.

    1998-01-01

    This monograph was prepared to give the practicing engineer a clear understanding of probability and statistics with special consideration to problems frequently encountered in aerospace engineering. It is conceived to be both a desktop reference and a refresher for aerospace engineers in government and industry. It could also be used as a supplement to standard texts for in-house training courses on the subject.

  5. 2012 Aerospace Medical Certification Statistical Handbook

    Science.gov (United States)

    2013-12-01

    2012 Aerospace Medical Certification Statistical Handbook Valerie J. Skaggs Ann I. Norris Civil Aerospace Medical Institute Federal Aviation...Certification Statistical Handbook December 2013 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Skaggs VJ, Norris AI 9...2.57 Hayfever 14,477 2.49 Asthma 12,558 2.16 Other general heart pathology (abnormal ECG, open heart surgery, etc.). Wolff-Parkinson-White syndrome

  6. Expanding the Use of Solid Modeling throughout the Engineering Curriculum.

    Science.gov (United States)

    Baxter, Douglas H.

    2001-01-01

    Presents the initial work that Rensselaer Polytechnic Institute has done to integrate solid modeling throughout the engineering curriculum. Aims to provide students the opportunity to use their solid modeling skills in several courses and show students how solid modeling tools can be used to help solve a variety of engineering problems.…

  7. Microstructure, mechanical behavior and corrosion properties of friction stir welded aluminum alloys used in the aerospace industry

    OpenAIRE

    Alfaro Mercado, Ulises

    2011-01-01

    Friction stir welding (FSW) has been identified as “key” technology for the production of primary aerospace structures, being able to substitute conventional riveted airframes. FSW is a solid state welding process that avoids any problems caused by the solidification of the melted weld pool. Besides the production of high quality similar joints from high strength aluminum alloys, it allows for joining materials of different metallurgical characteristics. However, problems concerning the corro...

  8. Solid Waste Management Holistic Decision Modeling

    OpenAIRE

    World Bank

    2008-01-01

    This study provides support to the Bank's ability to conduct client dialogue on solid waste management technology selection, and will contribute to client decision-making. The goal of the study was to fully explore the use of the United States Environmental Protection Agency and the Research Triangle Institute (EPA/RTI) holistic decision model to study alternative solid waste systems in a ...

  9. Guides to Aerospace Research and Development in NATO Countries.

    Science.gov (United States)

    1984-01-01

    The directory contains worldwide information Administrations et Services Aeroautiques. Designadores de Empresas Explotadoras about aviation/aerospace...ADVISORY GROUP FOR AEROSPACE RESEARCH AND DEVELOPMENT (ORGANISATION DU TRAITE DE L’ATLANTIQUE NORD) AGARD Report No.7 18 * GUIDES TO AEROSPACE RESEARCH...and transport containing also The Tithe and Keyword Index includes titles of all establishments listed in this highly professional photographs received

  10. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 21: Technological innovation and technical communications: Their place in aerospace engineering curricula. A survey of European, Japanese, and US Aerospace Engineers and Scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Holland, Maurita Peterson; Keene, Michael L.; Kennedy, John M.

    1991-01-01

    Aerospace engineers and scientists from Western Europe, Japan, and the United States were surveyed as part of the NASA/DoD Aerospace Knowledge Diffusion Research Project. Questionnaires were used to solicit their opinions regarding the following: (1) the importance of technical communications to their profession; (2) the use and production of technical communications; and (3) their views about the appropriate content of an undergraduate course in technical communications. The ability to communicate technical information effectively was very important to the aerospace engineers and scientists who participated in the study. A considerable portion of their working week is devoted to using and producing technical information. The types of technical communications used and produced varied within and among the three groups. The type of technical communication product used and produced appears to be related to respondents' professional duties. Respondents from the three groups made similar recommendations regarding the principles, mechanics, and on-the-job communications to be included in an undergraduate technical communications course for aerospace majors.

  11. State-of-the-Art Solid Waste Management Life-Cycle Modeling Workshop

    DEFF Research Database (Denmark)

    Damgaard, Anders; Levis, James W.

    There are many alternatives for the management of solid waste including recycling, biological treatment, thermal treatment and landfill disposal. In many cases, solid waste management systems include the use of several of these processes. Solid waste life-cycle assessment models are often used...... to evaluate the environmental consequences of various waste management strategies. The foundation of every life-cycle model is the development and use of process models to estimate the emissions from solid waste unit processes. The objective of this workshop is to describe life-cycle modeling of the solid...... waste processes and systems. The workshop will begin with an introduction to solid waste life-cycle modeling and available models, which will be followed by sessions on life-cycle process modeling for individual processes (e.g., landfills, biological treatment, and thermal treatment). The first part...

  12. Second Aerospace Environmental Technology Conference

    Science.gov (United States)

    Whitaker, A. F. (Editor); Clark-Ingram, M. (Editor)

    1997-01-01

    The mandated elimination of CFC'S, Halons, TCA, and other ozone depleting chemicals and specific hazardous materials has required changes and new developments in aerospace materials and processes. The aerospace industry has been involved for several years in providing product substitutions, redesigning entire production processes, and developing new materials that minimize or eliminate damage to the environment. These activities emphasize replacement cleaning solvents and their application, verification, compliant coatings including corrosion protection system and removal techniques, chemical propulsion effects on the environment, and the initiation of modifications to relevant processing and manufacturing specifications and standards.

  13. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 42: An analysis of the transfer of Scientific and Technical Information (STI) in the US aerospace industry

    Science.gov (United States)

    Kennedy, John M.; Pinelli, Thomas E.; Hecht, Laura F.; Barclay, Rebecca O.

    1994-01-01

    The U.S. aerospace industry has a long history of federal support for research related to its needs. Since the establishment of the National Advisory Committee for Aeronautics (NACA) in 1915, the federal government has provided continuous research support related to flight and aircraft design. This research has contributed to the international preeminence of the U.S. aerospace industry. In this paper, we present a sociological analysis of aerospace engineers and scientists and how their attitudes and behaviors impact the flow of scientific and technical information (STI). We use a constructivist framework to explain the spotty dissemination of federally funded aerospace research. Our research is aimed towards providing federal policymakers with a clearer understanding of how and when federally funded aerospace research is used. This understanding will help policymakers design improved information transfer systems that will aid the competitiveness of the U.S. aerospace industry.

  14. Numerical simulation of dynamics of brushless dc motors for aerospace and other applications. Volume 1: Model development and applications, part A

    Science.gov (United States)

    Demerdash, N. A. O.; Nehl, T. W.

    1979-01-01

    The development, fabrication and evaluation of a prototype electromechanical actuator (EMA) is discussed. Application of the EMA as a motor for control surfaces in aerospace flight is examined. A mathematical model of the EMA is developed for design optimization. Nonlinearities which complicate the mathematical model are discussed. The dynamics of the EMA from the underlying physical principles are determined and a discussion of similating the control logic by means of equivalent boolean expressions is presented.

  15. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 17: A comparison of the technical communication practices of Dutch and US aerospace engineers and scientists

    Science.gov (United States)

    Barclay, Rebecca O.; Pinelli, Thomas E.; Kennedy, John M.

    1993-01-01

    As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communications practices of Dutch and U.S. aerospace engineers and scientists. Both studies have the same seven objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communications to their profession; second, to determine the use and production of technical communications by aerospace engineers and scientists; third, to seek their views about the appropriate content of an undergraduate course in technical communications; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line data bases; fifth, to determine the use and importance of computer and information technology to them; sixth, to determine their use of electronic networks; and seventh, to determine their use of foreign and domestically produced technical reports. A self-administered questionnaire was distributed to aerospace engineers and scientists at the National Aerospace Laboratory (NLR), and NASA Ames Research Center, and the NASA Langley Research Center. The completion rates for the Dutch and U.S. surveys were 55 and 61 percent, respectively. Responses of the Dutch and U.S. participants to selected questions are presented.

  16. Meaning and value of cloud manufacturing platform for aerospace enterprises

    Science.gov (United States)

    Tang, Wei; Xu, Wei; Xin, Xin

    2017-08-01

    Aerospace manufacturing engineering technology status it is important symbol to measure the comprehensive strength of nation. This paper analyzes the meaning and value of aerospace enterprises, based on the concept of cloud manufacturing to the practical production and application, combined with the characteristics of aerospace enterprises.

  17. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 16: A comparison of the technical communications practices of Russian and US aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.

    1993-01-01

    As part of Phase 4 of the NASA/DOD Aerospace Knowledge Diffusion Project, two studies were conducted that investigated the technical communications practices of Russian and U.S. aerospace engineers and scientists. Both studies have the same five objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communications to their profession; second, to determine the use and production of technical communications by aerospace engineers and scientists; third, to seek their views about the appropriate content of an undergraduate course in technical communications; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line data bases; and fifth, to determine the use and importance of computer and information technology to them. A self-administered questionnaire was distributed to aerospace engineers and scientists at the Central Aero-Hydrodynamic Institute (TsAGI), NASA ARC, and NASA LaRC. The completion rates for the Russian and U.S. surveys were 64 and 61 percent, respectively. The responses of the Russian and U.S. participants, to selected questions, are presented in this report.

  18. Aerospace Toolbox---a flight vehicle design, analysis, simulation ,and software development environment: I. An introduction and tutorial

    Science.gov (United States)

    Christian, Paul M.; Wells, Randy

    2001-09-01

    This paper presents a demonstrated approach to significantly reduce the cost and schedule of non real-time modeling and simulation, real-time HWIL simulation, and embedded code development. The tool and the methodology presented capitalize on a paradigm that has become a standard operating procedure in the automotive industry. The tool described is known as the Aerospace Toolbox, and it is based on the MathWorks Matlab/Simulink framework, which is a COTS application. Extrapolation of automotive industry data and initial applications in the aerospace industry show that the use of the Aerospace Toolbox can make significant contributions in the quest by NASA and other government agencies to meet aggressive cost reduction goals in development programs. The part I of this paper provides a detailed description of the GUI based Aerospace Toolbox and how it is used in every step of a development program; from quick prototyping of concept developments that leverage built-in point of departure simulations through to detailed design, analysis, and testing. Some of the attributes addressed include its versatility in modeling 3 to 6 degrees of freedom, its library of flight test validated library of models (including physics, environments, hardware, and error sources), and its built-in Monte Carlo capability. Other topics to be covered in this part include flight vehicle models and algorithms, and the covariance analysis package, Navigation System Covariance Analysis Tools (NavSCAT). Part II of this paper, to be published at a later date, will conclude with a description of how the Aerospace Toolbox is an integral part of developing embedded code directly from the simulation models by using the Mathworks Real Time Workshop and optimization tools. It will also address how the Toolbox can be used as a design hub for Internet based collaborative engineering tools such as NASA's Intelligent Synthesis Environment (ISE) and Lockheed Martin's Interactive Missile Design Environment

  19. 77 FR 41891 - Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes

    Science.gov (United States)

    2012-07-17

    ... Certification Office, 1701 Columbia Avenue, College Park, GA 30337; phone 404-474-5548; fax 404-474-5605; email... directive (AD) for certain Gulfstream Aerospace Corporation Model G-IV, GIV-X, GV, and GV-SP airplanes. This... received, and other information. The street address for the Docket Office (phone: 800-647-5527) is in the...

  20. Cosserat modeling of cellular solids

    NARCIS (Netherlands)

    Onck, P.R.

    Cellular solids inherit their macroscopic mechanical properties directly from the cellular microstructure. However, the characteristic material length scale is often not small compared to macroscopic dimensions, which limits the applicability of classical continuum-type constitutive models. Cosserat

  1. Skill gap analysis and training needs in Indian aerospace industry

    Directory of Open Access Journals (Sweden)

    Premkumar Balaraman

    2016-12-01

    Full Text Available Purpose: The main objective of the paper is on assessing the global aerospace industry as well as Indian scenario, and attempts to assess the skill gaps and training needs of Indian aerospace industry.  Design/methodology/approach: The study is qualitative in nature, and employs wide array of qualitative tools which includes desktop study, focus group interviews and secondary sources of information. Around 10 focus groups were used in the study, with each focus group having a minimum of 6 members of experts in the aerospace and allied industries. The study evolved into a 2 staged one, with the first study elucidating the growing importance and potential of aerospace industry, justifying the significance to take forward the second part of the study. And the second study specifically focuses on skill gaps and training needs. Findings and Originality/value: The Study yields varied results on existing generic expectations of aerospace industry, specific needs of aerospace industry, identification of aerospace job categories unique to aerospace industry, key issues of training in Indian scenario and recommendations. The paper in summary reflects the current scenario of aerospace industry potentials for India and its likely impact on skills gap and training needs. Practical implications: Skills gap is a significant gap between an organization’s current capabilities and the skills it needs to achieve its goals. As a number of Global forecasts project, India as an emerging aviation market, the skill gaps in this sector is predicted to be huge and necessitates the study on assessing the skill gaps and its allied training needs. Originality/value: The Study is highly original and first one of its kind in reflecting the current situation of the skills gap and training needs in Indian Aerospace industry. The focus group interviews were conducted with the experts at various levels in the industyr without any bias yielding valid and realtime data for the

  2. Personality and organizational influences on aerospace human performance

    Science.gov (United States)

    Helmreich, Robert L.

    1989-01-01

    Individual and organizational influences on performance in aerospace environments are discussed. A model of personality with demonstrated validity is described along with reasons why personality's effects on performance have been underestimated. Organizational forces including intergroup conflict and coercive pressures are also described. It is suggested that basic and applied research in analog situations is needed to provide necessary guidance for planning future space missions.

  3. Crew factors in the aerospace workplace

    Science.gov (United States)

    Kanki, Barbara G.; Foushee, H. C.

    1990-01-01

    The effects of technological change in the aerospace workplace on pilot performance are discussed. Attention is given to individual and physiological problems, crew and interpersonal problems, environmental and task problems, organization and management problems, training and intervention problems. A philosophy and conceptual framework for conducting research on these problems are presented and two aerospace studies are examined which investigated: (1) the effect of leader personality on crew effectiveness and (2) the working undersea habitat known as Aquarius.

  4. Advanced methods of solid oxide fuel cell modeling

    CERN Document Server

    Milewski, Jaroslaw; Santarelli, Massimo; Leone, Pierluigi

    2011-01-01

    Fuel cells are widely regarded as the future of the power and transportation industries. Intensive research in this area now requires new methods of fuel cell operation modeling and cell design. Typical mathematical models are based on the physical process description of fuel cells and require a detailed knowledge of the microscopic properties that govern both chemical and electrochemical reactions. ""Advanced Methods of Solid Oxide Fuel Cell Modeling"" proposes the alternative methodology of generalized artificial neural networks (ANN) solid oxide fuel cell (SOFC) modeling. ""Advanced Methods

  5. 76 FR 23339 - Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2011-04-26

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (11-043)] Aerospace Safety Advisory Panel; Meeting AGENCY: National Aeronautics and Space Administration (NASA). ACTION: Notice of meeting... Register of April 6, 2011, announcing a meeting of the Aerospace Safety Advisory Panel (ASAP) to take place...

  6. Scoping Aerospace: Tracking Federal Procurement and R&D Spending in the Aerospace Sector

    National Research Council Canada - National Science Library

    Hogan, Thor; Fossum, Donna; Johnson, Dana J; Painter, Lawrence S

    2005-01-01

    .... The study provides a detailed examination of the Federal Procurement Data System (FPDS), with the specific purpose of tracking all government aerospace procurement and research and development (R AND D...

  7. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 33: Technical communications practices and the use of information technologies as reported by Dutch and US aerospace engineers

    Science.gov (United States)

    Barclay, Rebecca O.; Pinelli, Thomas E.; Tan, Axel S. T.; Kennedy, John M.

    1993-01-01

    As part of Phase 4 of the NASA/DOD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communications practices of Dutch and U.S. aerospace engineers and scientists. A self-administered questionnaire was distributed to aerospace engineers and scientists at the National Aerospace Laboratory (The Netherlands), and NASA ARC (U.S.), and NASA LaRC (U.S.). This paper presents responses of the Dutch and U.S. participants to selected questions concerning four of the seven project objectives: determining the importance of technical communications to aerospace engineering professionals, investigating the production of technical communications, examining the use and importance of computer and information technology, and exploring the use of electronic networks.

  8. Derivative Geometric Modeling of Basic Rotational Solids on CATIA

    Institute of Scientific and Technical Information of China (English)

    MENG Xiang-bao; PAN Zi-jian; ZHU Yu-xiang; LI Jun

    2011-01-01

    Hybrid models derived from rotational solids like cylinders, cones and spheres were implemented on CATIA software. Firstly, make the isosceles triangular prism, cuboid, cylinder, cone, sphere, and the prism with tangent conic and curved triangle ends, the cuboid with tangent cylindrical and curved rectangle ends, the cylinder with tangent spherical and curved circular ends as the basic Boolean deference units to the primary cylinders, cones and spheres on symmetrical and some critical geometric conditions, forming a series of variant solid models. Secondly, make the deference units above as the basic union units to the main cylinders, cones, and spheres accordingly, forming another set of solid models. Thirdly, make the tangent ends of union units into oblique conic, cylindrical, or with revolved triangular pyramid, quarterly cylinder and annulus ends on sketch based features to the main cylinders, cones, and spheres repeatedly, thus forming still another set of solid models. It is expected that these derivative models be beneficial both in the structure design, hybrid modeling, and finite element analysis of engineering components and in comprehensive training of spatial configuration of engineering graphics.

  9. Federal R and D Reductions, Market Share, and Aerospace Information Usage

    Science.gov (United States)

    Rocker, JoAnne; Roncaglia, George

    2000-01-01

    Reductions in federally funded research have a rippling effect over the entire aerospace industry. The decline in federal R&D spending in aerospace in recent years coincides with declines in U.S. aerospace market share, One of the lesser-understood factors in the declining U.S. market share may be the differing ways and intensity with which the U.S. and its competitors approach another trend, the increasing availability of large amounts of aerospace research information on the World Wide Web. The U.S. has been a pioneer in making research information available in electronic form, and the international community has long been a heavy consumer of that information. In essence, the U.S. contributes to the research efforts of its competitors, thus contributing to foreign aerospace consortiums efforts to gain market share in the aerospace industry, This may be a cautionary note to the U.S. aerospace industry to consider the use of R&D output in its own development and strategy because the foreign competition is using the U.S. scientific and technical literature.

  10. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 30: Computer-Mediated Communication (CMC) and the communication of technical information in aerospace. Ph.D Thesis - Rensselaer Polytechnic Inst. Final Report

    Science.gov (United States)

    Murphy, Daniel J.; Pinelli, Thomas E.

    1994-01-01

    This research used survey research to examine the use of communication media in general and electronic media specifically in the U.S. aerospace industry. The survey population included 1,006 randomly selected U.S. aerospace engineers and scientists who belong to the American Institute of Aeronautics and Astronautics (AIAA). Survey data were compared with qualitative information obtained from 32 AIAA members in telephone and face-to-face conversations. The Information Processing (IP) model developed by Tushman and Nadler and Daft and Lengel constituted the study's theoretical basis. This research analyzed responses regarding communication methods of U.S. aerospace engineers and scientists who create use and disseminate aerospace knowledge and explored selected contextual environmental variables related to media use and effective performance. The results indicate that uncertainty is significantly reduced in environments when levels of analyzability are high. When uncertainty is high there is significantly more use of electronic media. However no relation was found between overall effectiveness and media use in environments stratified by levels by analyzability or equivocality. The results indicate modest support for the influences of uncertainty and analyzability on electronic media use. Although most respondents reported that electronic networks are important for their work the data suggest that there are sharply disparate levels of use.

  11. An example of active learning in Aerospace Engineering

    NARCIS (Netherlands)

    Brugemann, V.P.; Brummelen, van E.H.; Melkert, J.A.; Kamp, A.; Saunders-Smits, G.N.; Reith, B.A.; Zandbergen, B.T.C.; Graaf, de E.; Saunders-Smits, G.N.; Nieweg, M.R.

    2005-01-01

    This paper is a showcase for an on-going active learning capstone design project in the BSe. programme at the Faculty of Aerospace Engineering at Delft University of Technology. In multi-disciplinary teams supervised by tutors from different backgrounds students work towards an Aerospace (related)

  12. Adopting exergy analysis for use in aerospace

    Science.gov (United States)

    Hayes, David; Lone, Mudassir; Whidborne, James F.; Camberos, José; Coetzee, Etienne

    2017-08-01

    Thermodynamic analysis methods, based on an exergy metric, have been developed to improve system efficiency of traditional heat driven systems such as ground based power plants and aircraft propulsion systems. However, in more recent years interest in the topic has broadened to include applying these second law methods to the field of aerodynamics and complete aerospace vehicles. Work to date is based on highly simplified structures, but such a method could be shown to have benefit to the highly conservative and risk averse commercial aerospace sector. This review justifies how thermodynamic exergy analysis has the potential to facilitate a breakthrough in the optimization of aerospace vehicles based on a system of energy systems, through studying the exergy-based multidisciplinary design of future flight vehicles.

  13. Modelling and Experimental Testing of Hybrid Joints Made of: Aluminium Adherends, Adhesive Layers and Rivets for Aerospace Applications

    Directory of Open Access Journals (Sweden)

    Sadowski T.

    2017-09-01

    Full Text Available The contemporary demands in different branches of engineering require application of new multi-component materials and structural systems. Appropriately chosen joining technology can offer significant enhancement of structural system performance in terms of effectiveness, reliability, safety and other design criteria. The modern applications of complex joints are of great technological interest as they permit to combine and to enhance the individual effects of each kind of joint. This is of great importance for modern applications in different branches of engineering: aerospace, mechanical and civil. Therefore in this paper we will focus on the analysis of mechanical response of adhesive joint of aluminium strips reinforced by rivets. The aim of the paper is to investigate experimentally the mechanical behaviour of adhesive joint of aluminium strips reinforced by rivets for industrial applications in aerospace. The considered joint was subjected to uniaxial loading. The tests in this paper were performed for: • classical adhesive joint in order to investigate material parameters for numerical modelling of the hybrid joint • hybrid joining of the structural elements in order to investigate the reinforcement effect. The experiments with application of digital image ARAMIS system allowed for on-line monitoring of the deformation process of the considered joining elements. The particular distributions of displacement fields at the joint surface were estimated for any stage of loading process. Numerical modelling was performed for experimentally investigated specimens. The materials parameters, necessary for calculation, were estimated from experiments. FEA modelling was done with the help of ABAQUS code.

  14. Challenges for Insertion of Structural Nanomaterials in Aerospace Applications

    Science.gov (United States)

    Sochi, Emilie J.

    2012-01-01

    In the two decades since Iijima's report on carbon nanotubes (CNT), there has been great interest in realizing the benefits of mechanical properties observed at the nanoscale in large-scale structures. The weight savings possible due to dramatic improvements in mechanical properties relative to state-of-the-art material systems can be game changing for applications like aerospace vehicles. While there has been significant progress in commercial production of CNTs, major aerospace applications that take advantage of properties offered by this material have yet to be realized. This paper provides a perspective on the technical challenges and barriers for insertion of CNTs as an emerging material technology in aerospace applications and proposes approaches that may reduce the typical timeframe for technology maturation and insertion into aerospace structures.

  15. Fracture mechanics of piezoelectric and ferroelectric solids

    CERN Document Server

    Fang, Daining

    2013-01-01

    Fracture Mechanics of Piezoelectric and Ferroelectric Solids presents a systematic and comprehensive coverage of the fracture mechanics of piezoelectric/ferroelectric materials, which includes the theoretical analysis, numerical computations and experimental observations. The main emphasis is placed on the mechanics description of various crack problems such static, dynamic and interface fractures as well as the physical explanations for the mechanism of electrically induced fracture. The book is intended for postgraduate students, researchers and engineers in the fields of solid mechanics, applied physics, material science and mechanical engineering. Dr. Daining Fang is a professor at the School of Aerospace, Tsinghua University, China; Dr. Jinxi Liu is a professor at the Department of Engineering Mechanics, Shijiazhuang Railway Institute, China.

  16. Biological effect of aerospace environment on alfalfa

    International Nuclear Information System (INIS)

    Zhang Yuexue; Liu Jielin; Han Weibo; Tang Fenglan; Hao Ruochao; Shang Chen; DuYouying; Li Jikai; Wang Changshan

    2009-01-01

    The biological effect of aerospace environment on two varieties of Medicago sativa L. was studied. In M 1 germination results showed that aerospace environment increased cell division and the number of micronucleus, changed germination rate, caused seedling aberrations. Cytogenetical and seedling aberration of Zhaodong showed more sensitivity than Longmu 803. Branches and fresh weight of Zhaodong had shown more serious damage than control and Longmu 803. (authors)

  17. Geometric data transfer between CAD systems: solid models

    DEFF Research Database (Denmark)

    Kroszynski, Uri; Palstroem, Bjarne; Trostmann, Erik

    1989-01-01

    The first phase of the ESPRIT project CAD*I resulted in a specification for the exchange of solid models as well as in some pilot implementations of processors based on this specification. The authors summarize the CAD*I approach, addressing the structure of neutral files for solids, entities......, and attributes supporting three kinds of representations: facilities for the transfer of parametric designs; referencing library components; and other general mechanisms. They also describe the current state of the specification and processor implementations and include an example of a CAD*I neutral file....... Results from cycle and intersystem solid model transfer tests are presented, showing the practicality of the CAD*I proposal. B-rep model transfer results are discussed in some detail. The relationship of this work to standardization efforts is outlined...

  18. Inference-based procedural modeling of solids

    KAUST Repository

    Biggers, Keith

    2011-11-01

    As virtual environments become larger and more complex, there is an increasing need for more automated construction algorithms to support the development process. We present an approach for modeling solids by combining prior examples with a simple sketch. Our algorithm uses an inference-based approach to incrementally fit patches together in a consistent fashion to define the boundary of an object. This algorithm samples and extracts surface patches from input models, and develops a Petri net structure that describes the relationship between patches along an imposed parameterization. Then, given a new parameterized line or curve, we use the Petri net to logically fit patches together in a manner consistent with the input model. This allows us to easily construct objects of varying sizes and configurations using arbitrary articulation, repetition, and interchanging of parts. The result of our process is a solid model representation of the constructed object that can be integrated into a simulation-based environment. © 2011 Elsevier Ltd. All rights reserved.

  19. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 40: Technical communications in aerospace education: A study of AIAA student members

    Science.gov (United States)

    Kennedy, John M.; Pinelli, Thomas E.; Barclay, Rebecca O.

    1994-01-01

    This paper describes the preliminary analysis of a survey of the American Institute of Aeronautics and Astronautics (AIAA) student members. In the paper we examine (1) the demographic characteristics of the students, (2) factors that affected their career decisions, (3) their career goals and aspirations, and (4) their training in technical communication and techniques for finding and using aerospace scientific and technical information (STI). We determine that aerospace engineering students receive training in technical communication skills and the use of STI. While those in the aerospace industry think that more training is needed, we believe the students receive the appropriate amount of training. We think that the differences between the amount of training students receive and the perception of training needs is related partially to the characteristics of the students and partially to the structure of the aerospace STI dissemination system. Overall, we conclude that the students' technical communication training and knowledge of STI, while limited by external forces, makes it difficult for students to achieve their career goals.

  20. High-Performing, Low-Temperature-Operating, Long-Lifetime Aerospace Lubricants

    Science.gov (United States)

    Joshi, Prakash

    2015-01-01

    Long-duration space exploration will require spacecraft systems that can operate effectively over several years with minimal or no maintenance. Aerospace lubricants are key components of spacecraft systems. Physical Sciences Inc., has synthesized and characterized novel ionic liquids for use in aerospace lubricants that contribute to decreased viscosity, friction, and wear in aerospace systems. The resulting formulations offer low vapor pressure and outgassing properties and thermal stability up to 250 C. They are effective for use at temperatures as low as -70 C and provide long-term operational stability in aerospace systems. In Phase II, the company scaled several new ionic liquids and evaluated a novel formulation in a NASA testbed. The resulting lubricant compounds will offer lower volatility, decreased corrosion, and better tribological characteristics than standard liquid lubricants, particularly at lower temperatures.

  1. Aerospace manpower transfer to small business enterprises

    Science.gov (United States)

    Green, M. K.

    1972-01-01

    The feasibility of a program to effect transfer of aerospace professional people from the ranks of the unemployed into gainful employment in the small business community was investigated. The effectiveness of accomplishing transfer of technology from the aerospace effort into the private sector through migration of people rather than products or hardware alone was also studied. Two basic methodologies were developed. One involves the matching of ex-aerospace professionals and small companies according to their mutual needs. A training and indoctrination program is aimed at familiarizing the professional with the small company environment, and a program of follow-up counseling is defined. The second methodology incorporates efforts to inform and arouse interest among the nonaerospace business community toward affirmative action programs that will serve mutual self-interests of the individuals, companies, and communities involved.

  2. Converting boundary representation solid models to half-space representation models for Monte Carlo analysis

    International Nuclear Information System (INIS)

    Davis, J. E.; Eddy, M. J.; Sutton, T. M.; Altomari, T. J.

    2007-01-01

    Solid modeling computer software systems provide for the design of three-dimensional solid models used in the design and analysis of physical components. The current state-of-the-art in solid modeling representation uses a boundary representation format in which geometry and topology are used to form three-dimensional boundaries of the solid. The geometry representation used in these systems is cubic B-spline curves and surfaces - a network of cubic B-spline functions in three-dimensional Cartesian coordinate space. Many Monte Carlo codes, however, use a geometry representation in which geometry units are specified by intersections and unions of half-spaces. This paper describes an algorithm for converting from a boundary representation to a half-space representation. (authors)

  3. 48 CFR 1852.244-70 - Geographic participation in the aerospace program.

    Science.gov (United States)

    2010-10-01

    ... the aerospace program. 1852.244-70 Section 1852.244-70 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.244-70 Geographic participation in the aerospace program. As prescribed in 1844.204-70, insert the following clause: Geographic Participation in the Aerospace Program (APR 1985) (a...

  4. Emerging Needs for Pervasive Passive Wireless Sensor Networks on Aerospace Vehicles

    Science.gov (United States)

    Wilson, William C.; Juarez, Peter D.

    2014-01-01

    NASA is investigating passive wireless sensor technology to reduce instrumentation mass and volume in ground testing, air flight, and space exploration applications. Vehicle health monitoring systems (VHMS) are desired on all aerospace programs to ensure the safety of the crew and the vehicles. Pervasive passive wireless sensor networks facilitate VHMS on aerospace vehicles. Future wireless sensor networks on board aerospace vehicles will be heterogeneous and will require active and passive network systems. Since much has been published on active wireless sensor networks, this work will focus on the need for passive wireless sensor networks on aerospace vehicles. Several passive wireless technologies such as microelectromechanical systems MEMS, SAW, backscatter, and chipless RFID techniques, have all shown potential to meet the pervasive sensing needs for aerospace VHMS applications. A SAW VHMS application will be presented. In addition, application areas including ground testing, hypersonic aircraft and spacecraft will be explored along with some of the harsh environments found in aerospace applications.

  5. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 29: A comparison of the technical communications practices of Japanese and US aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communications practices of Japanese and U.S. aerospace engineers and scientists. Both studies have the same seven objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communications to their profession; second, to determine the use and production of technical communications by aerospace engineers and scientists; third; to seek their views about the appropriate content of an undergraduate course in technical communications; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line data bases; fifth, to determine the use and importance of computer and information technology to them; sixth, to determine their use of electronic networks; and seventh, to determine their use of foreign and domestically produced technical reports. A self-administered questionnaire was distributed to aerospace engineers and scientists in Japan and at the NASA Ames Research Center and the NASA Langley Research Center. The completion rates for the Japanese and U.S. surveys were 85 and 61 percent, respectively. Responses of the Japanese and U.S. participants to selected questions are presented in this report.

  6. Current Trends in Aerospace Engineering Education on Taiwan.

    Science.gov (United States)

    Hsieh, Sheng-Jii

    A proposal for current trends in Aerospace Engineering Education on Taiwan has been drawn from the suggestions made after a national conference of "Workshop on Aerospace Engineering Education Reform." This workshop was held in January 18-20, 1998, at the Institute of Aeronautics and Astronautics, National Cheng Kung University, Tainan,…

  7. A mathematical model of combustion kinetics of municipal solid ...

    African Journals Online (AJOL)

    Municipal Solid Waste has become a serious environmental problem troubling many cities. In this paper, a mathematical model of combustion kinetics of municipal solid waste with focus on plastic waste was studied. An analytical solution is obtained for the model. From the numerical simulation, it is observed that the ...

  8. MEMS for automotive and aerospace applications

    CERN Document Server

    Kraft, Michael

    2013-01-01

    MEMS for automotive and aerospace applications reviews the use of Micro-Electro-Mechanical-Systems (MEMS) in developing solutions to the unique challenges presented by the automotive and aerospace industries.Part one explores MEMS for a variety of automotive applications. The role of MEMS in passenger safety and comfort, sensors for automotive vehicle stability control applications and automotive tire pressure monitoring systems are considered, along with pressure and flow sensors for engine management, and RF MEMS for automotive radar sensors. Part two then goes on to explore MEMS for

  9. Chromatography–mass spectrometry in aerospace industry

    International Nuclear Information System (INIS)

    Buryak, Alexey K; Serduk, T M

    2013-01-01

    The applications of chromatography–mass spectrometry in aerospace industry are considered. The primary attention is devoted to the development of physicochemical grounds of the use of various chromatography–mass spectrometry procedures to solve topical problems of this industry. Various methods for investigation of the composition of rocket fuels, surfaces of structural materials and environmental media affected by aerospace activities are compared. The application of chromatography–mass spectrometry for the development and evaluation of processes for decontaminations of equipment, industrial wastes and soils from rocket fuel components is substantiated. The bibliography includes 135 references.

  10. NASA/DoD Aerospace Knowledge Diffusion Research Project. XXXIII - Technical communications practices and the use of information technologies as reported by Dutch and U.S. aerospace engineers

    Science.gov (United States)

    Barclay, Rebecca O.; Pinelli, Thomas E.; Tan, Axel S. T.; Kennedy, John M.

    1993-01-01

    As part of Phase 4 of the NASA/DOD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communications practices of Dutch and U.S. aerospace engineers and scientists. A self-administered questionnaire was distributed to aerospace engineers and scientists at the National Aerospace Laboratory (The Netherlands), and NASA Ames Research Center (U.S.), and the NASA Langley Research Center (U.S.). This paper presents responses of the Dutch and U.S. participants to selected questions about four of the seven project objectives: determining the importance of technical communications to aerospace engineering professionals, investigating the production of technical communications, examining the use and importance of computer and information technology, and exploring the use of electronic networks.

  11. Solid modeling research at Lawrence Livermore National Laboratory: 1982-1985

    International Nuclear Information System (INIS)

    Kalibjian, J.R.

    1985-01-01

    The Lawrence Livermore National Laboratory has sponsored solid modeling research for the past four years to assess this new technology and to determine its potential benefits to the Nuclear Weapons Complex. We summarize here the results of five projects implemented during our effort. First, we have installed two solid modeler codes, TIPS-1 (Technical Information Processing System-1) and PADL-2 (Part and Assembly Description Language), on the Laboratory's CRAY-1 computers. Further, we have extended the geometric coverage and have enhanced the graphics capabilities of the TIPS-1 modeler. To enhance solid modeler performance on our OCTOPUS computer system, we have also developed a method to permit future use of the Laboratory's network video system to provide high-resolution, shaded images at users' locations. Finally, we have begun to implement code that will link solid-modeler data bases to finite-element meshing codes

  12. Performance prediction of a synchronization link for distributed aerospace wireless systems.

    Science.gov (United States)

    Wang, Wen-Qin; Shao, Huaizong

    2013-01-01

    For reasons of stealth and other operational advantages, distributed aerospace wireless systems have received much attention in recent years. In a distributed aerospace wireless system, since the transmitter and receiver placed on separated platforms which use independent master oscillators, there is no cancellation of low-frequency phase noise as in the monostatic cases. Thus, high accurate time and frequency synchronization techniques are required for distributed wireless systems. The use of a dedicated synchronization link to quantify and compensate oscillator frequency instability is investigated in this paper. With the mathematical statistical models of phase noise, closed-form analytic expressions for the synchronization link performance are derived. The possible error contributions including oscillator, phase-locked loop, and receiver noise are quantified. The link synchronization performance is predicted by utilizing the knowledge of the statistical models, system error contributions, and sampling considerations. Simulation results show that effective synchronization error compensation can be achieved by using this dedicated synchronization link.

  13. Third Aerospace Environmental Technology Conference

    Science.gov (United States)

    Whitaker, A. F. (Editor); Cross, D. R. (Editor); Caruso, S. V. (Editor); Clark-Ingram, M. (Editor)

    1999-01-01

    The elimination of CFC's, Halons, TCA, other ozone depleting chemicals, and specific hazardous materials is well underway. The phaseout of these chemicals has mandated changes and new developments in aerospace materials and processes. We are beyond discovery and initiation of these new developments and are now in the implementation phase. This conference provided a forum for materials and processes engineers, scientists, and managers to describe, review, and critically assess the evolving replacement and clean propulsion technologies from the standpoint of their significance, application, impact on aerospace systems, and utilization by the research and development community. The use of these new technologies, their selection and qualification, their implementation, and the needs and plans for further developments are presented.

  14. Research and Application of Virtual Simulation Technology in the Aerospace Bearing Design and Manufacture

    Directory of Open Access Journals (Sweden)

    Jiangshan Liu

    2018-01-01

    Full Text Available Bearings are widely used in aerospace and other fields, its performance directly affects the production efficiency and safety. Nowadays, virtual simulation technology has become an indispensable part of intelligent manufacturing field. As a virtual simulation technology, FEA has been widely used in bearing design. China needs to import many aerospace bearings every year in aerospace area, Chinese national defense and other high precision technology is limited because the blockade of advanced bearing technology. We can use dynamics modeling and virtual simulation technology to achieve the predictive design, and strive to achieve foreign level. In this paper, the author proposed a method of bearing design based on virtual simulation technology. The factors of bearing which affect the dynamic characteristics are considered, the process of design bearing based on virtual simulation is also considered. According to the different design parameters, the simulation results are used to verify the rationality, these can reduce the cost and improve the reliability. The virtual simulation technology is applied to design the 7016C angular contact ball bearing which used in aerospace area, and supported decision-making in structure design and data analyze. Finally, The feasibility of this method is verified by experiments..

  15. Polymer and ceramic nanocomposites for aerospace applications

    Science.gov (United States)

    Rathod, Vivek T.; Kumar, Jayanth S.; Jain, Anjana

    2017-11-01

    This paper reviews the potential of polymer and ceramic matrix composites for aerospace/space vehicle applications. Special, unique and multifunctional properties arising due to the dispersion of nanoparticles in ceramic and metal matrix are briefly discussed followed by a classification of resulting aerospace applications. The paper presents polymer matrix composites comprising majority of aerospace applications in structures, coating, tribology, structural health monitoring, electromagnetic shielding and shape memory applications. The capabilities of the ceramic matrix nanocomposites to providing the electromagnetic shielding for aircrafts and better tribological properties to suit space environments are discussed. Structural health monitoring capability of ceramic matrix nanocomposite is also discussed. The properties of resulting nanocomposite material with its disadvantages like cost and processing difficulties are discussed. The paper concludes after the discussion of the possible future perspectives and challenges in implementation and further development of polymer and ceramic nanocomposite materials.

  16. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 55: Career goals and educational preparation of aerospace engineering and science students: An international perspective

    Science.gov (United States)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.

    1995-01-01

    Results are presented of a survey of aerospace engineering and science students conducted in India, Japan, Russia, the United Kingdom, and the United States. The similarities and differences among aerospace engineering and science students from the five countries are examined in the context of two general aspects of educational experience. First, the extent to which students differ regarding the factors that led to the choice of a career in aerospace, their current levels of satisfaction with that choice, and career-related goals and objectives is considered. Second, the importance of certain communications/information-use skills for professional use is examined, as well as the frequency of use and importance of specific information sources and products to meet students' educational needs. Overall, the students who participated in this research remain relatively happy with the choice of a career in aerospace engineering, despite pessimism in some quarters about the future of the industry. Regardless of national identity, aerospace engineering and science students appear to share a similar vision of the profession in terms of their career goals and aspirations. The data also indicate that aerospace engineering and science students are well aware of the importance of communications/information-use skills to professional success and that competency in these skills will help them to be productive members of their profession. Collectively, all of the students appear to use and value similar information sources and products, although some differences appear by country.

  17. Introduction to NASA's Academy of Aerospace Quality

    OpenAIRE

    Smith, Alice; Smith, Jeffrey

    2016-01-01

    The NASA Academy of Aerospace Quality (AAQ) is an internet-based public domain forum of quality assurance-related educational modules for students and faculty at academic institutions targeting those involved in aerospace research, technology development, and payload design and development including Cube Sats, Small Sats, Nano Sats, Rockets and High Altitude Balloons. The target users are university project and research teams but the academy has also been used by K-12 teams, independent space...

  18. WATEQ3 geochemical model: thermodynamic data for several additional solids

    International Nuclear Information System (INIS)

    Krupka, K.M.; Jenne, E.A.

    1982-09-01

    Geochemical models such as WATEQ3 can be used to model the concentrations of water-soluble pollutants that may result from the disposal of nuclear waste and retorted oil shale. However, for a model to competently deal with these water-soluble pollutants, an adequate thermodynamic data base must be provided that includes elements identified as important in modeling these pollutants. To this end, several minerals and related solid phases were identified that were absent from the thermodynamic data base of WATEQ3. In this study, the thermodynamic data for the identified solids were compiled and selected from several published tabulations of thermodynamic data. For these solids, an accepted Gibbs free energy of formation, ΔG 0 /sub f,298/, was selected for each solid phase based on the recentness of the tabulated data and on considerations of internal consistency with respect to both the published tabulations and the existing data in WATEQ3. For those solids not included in these published tabulations, Gibbs free energies of formation were calculated from published solubility data (e.g., lepidocrocite), or were estimated (e.g., nontronite) using a free-energy summation method described by Mattigod and Sposito (1978). The accepted or estimated free energies were then combined with internally consistent, ancillary thermodynamic data to calculate equilibrium constants for the hydrolysis reactions of these minerals and related solid phases. Including these values in the WATEQ3 data base increased the competency of this geochemical model in applications associated with the disposal of nuclear waste and retorted oil shale. Additional minerals and related solid phases that need to be added to the solubility submodel will be identified as modeling applications continue in these two programs

  19. SPATIAL MODELING OF SOLID-STATE REGULAR POLYHEDRA (SOLIDS OF PLATON IN AUTOCAD SYSTEM

    Directory of Open Access Journals (Sweden)

    P. V. Bezditko

    2009-03-01

    Full Text Available This article describes the technology of modeling regular polyhedra by graphic methods. The authors came to the conclusion that in order to create solid models of regular polyhedra the method of extrusion is best to use.

  20. Modeling all-solid-state Li-ion batteries

    NARCIS (Netherlands)

    Danilov, D.; Niessen, R.A.H.; Notten, P.H.L.

    2011-01-01

    A mathematical model for all-solid-state Li-ion batteries is presented. The model includes the charge transfer kinetics at the electrode/electrolyte interface, diffusion of lithium in the intercalation electrode, and diffusion and migration of ions in the electrolyte. The model has been applied to

  1. Geological modeling of a stratified deposit with CAD-Based solid model automation

    Directory of Open Access Journals (Sweden)

    Ayten Eser

    Full Text Available Abstract The planning stages of mining activities require many comprehensive and detailed analyses. Determining the correct orebody model is the first stage and one of the most important. Three-dimensional solid modeling is one of the significant methods that can examine the position and shape of the ore deposit. Although there are many different types of mining software for determining a solid model, many users try to build geological models in the computer without knowing how these software packages work. As researchers on the subject, we wanted to answer the question "How would we do it". For this purpose, a system was developed for generating solid models using data obtained from boreholes. Obtaining this model in an AutoCAD environment will be important for geologists and engineers. Developed programs were first tested with virtual borehole data belonging to a virtual deposit. Then the real borehole data of a cement raw material site were successfully applied. This article allows readers not only to see a clear example of the programming approach to layered deposits but also to produce more complicated software in this context. Our study serves as a window to understanding the geological modeling process.

  2. Introduction: Aims and Requirements of Future Aerospace Vehicles. Chapter 1

    Science.gov (United States)

    Rodriguez, Pedro I.; Smeltzer, Stanley S., III; McConnaughey, Paul (Technical Monitor)

    2001-01-01

    The goals and system-level requirements for the next generation aerospace vehicles emphasize safety, reliability, low-cost, and robustness rather than performance. Technologies, including new materials, design and analysis approaches, manufacturing and testing methods, operations and maintenance, and multidisciplinary systems-level vehicle development are key to increasing the safety and reducing the cost of aerospace launch systems. This chapter identifies the goals and needs of the next generation or advanced aerospace vehicle systems.

  3. Contribution to the modelling of gas-solid reactions and reactors

    International Nuclear Information System (INIS)

    Patisson, F.

    2005-09-01

    Gas-solid reactions control a great number of major industrial processes involving matter transformation. This dissertation aims at showing that mathematical modelling is a useful tool for both understanding phenomena and optimising processes. First, the physical processes associated with a gas-solid reaction are presented in detail for a single particle, together with the corresponding available kinetic grain models. A second part is devoted to the modelling of multiparticle reactors. Different approaches, notably for coupling grain models and reactor models, are illustrated through various case studies: coal pyrolysis in a rotary kiln, production of uranium tetrafluoride in a moving bed furnace, on-grate incineration of municipal solid wastes, thermogravimetric apparatus, nuclear fuel making, steel-making electric arc furnace. (author)

  4. NASA Aerospace Flight Battery Program: Generic Safety, Handling and Qualification Guidelines for Lithium-Ion (Li-Ion) Batteries; Availability of Source Materials for Lithium-Ion (Li-Ion) Batteries; Maintaining Technical Communications Related to Aerospace Batteries (NASA Aerospace Battery Workshop). Volume 1, Part 1

    Science.gov (United States)

    Manzo, Michelle A.; Brewer, Jeffrey C.; Bugga, Ratnakumar V.; Darcy, Eric C.; Jeevarajan, Judith A.; McKissock, Barbara I.; Schmitz, Paul C.

    2010-01-01

    This NASA Aerospace Flight Battery Systems Working Group was chartered within the NASA Engineering and Safety Center (NESC). The Battery Working Group was tasked to complete tasks and to propose proactive work to address battery related, agency-wide issues on an annual basis. In its first year of operation, this proactive program addressed various aspects of the validation and verification of aerospace battery systems for NASA missions. Studies were performed, issues were discussed and in many cases, test programs were executed to generate recommendations and guidelines to reduce risk associated with various aspects of implementing battery technology in the aerospace industry. This document contains Part 1 - Volume I: Generic Safety, Handling and Qualification Guidelines for Lithium-Ion (Li-Ion) Batteries, Availability of Source Materials for Lithium-Ion (Li-Ion) Batteries, and Maintaining Technical Communications Related to Aerospace Batteries (NASA Aerospace Battery Workshop).

  5. 75 FR 75882 - Airworthiness Directives; British Aerospace Regional Aircraft Models Jetstream Series 3101 and...

    Science.gov (United States)

    2010-12-07

    ... the FAA, call 816-329-4148. FOR FURTHER INFORMATION CONTACT: Taylor Martin, Aerospace Engineer, FAA...; fax: (816) 329-4090; e-mail: taylor[email protected] . SUPPLEMENTARY INFORMATION: Discussion We issued a... requires the application of safe life limits to these components. Actions and Compliance (f) Unless already...

  6. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 69: Writing for the Aerospace Industry. Chapter 3; The Practice of Technical and Scientific Communication: Writing in Professional Contexts

    Science.gov (United States)

    Barclay, Rebecca O.; Pinelli, Thomas E.

    1997-01-01

    The large and complex aerospace industry, which employed approximately 850,000 people in 1994 (Aerospace Facts, 1994-95, p. 11), plays a vital role in the nation's economy. Although only a small percentage of those employed in aerospace are technical communicators, they perform a wide variety of communication duties in government and the private sector.

  7. Oklahoma Aerospace Intellectual Capital/Educational Recommendations: An Inquiry of Oklahoma Aerospace Executives

    Science.gov (United States)

    Nelson, Erin M.

    2010-01-01

    Scope and Method of Study: The purpose of this qualitative study was to conduct detailed personal interviews with aerospace industry executives/managers from both the private and military sectors from across Oklahoma to determine their perceptions of intellectual capital needs of the industry. Interviews with industry executives regarding…

  8. Automated procedures for sizing aerospace vehicle structures /SAVES/

    Science.gov (United States)

    Giles, G. L.; Blackburn, C. L.; Dixon, S. C.

    1972-01-01

    Results from a continuing effort to develop automated methods for structural design are described. A system of computer programs presently under development called SAVES is intended to automate the preliminary structural design of a complete aerospace vehicle. Each step in the automated design process of the SAVES system of programs is discussed, with emphasis placed on use of automated routines for generation of finite-element models. The versatility of these routines is demonstrated by structural models generated for a space shuttle orbiter, an advanced technology transport,n hydrogen fueled Mach 3 transport. Illustrative numerical results are presented for the Mach 3 transport wing.

  9. Protons, Aerospace, and Electronics: A National Interest

    Science.gov (United States)

    LaBel, Kenneth A.; Turflinger, Thomas L.

    2018-01-01

    The aerospace and semiconductor industries lost approx. 2000 hours annually of research access when IUCF closed. An ad hoc team between the U.S. government and industry was formed to evaluate other facility options. In this presentation, we will discuss: 1) Why aerospace, semiconductor manufacturers, and others are interested in proton facility access, as well as, 2) Some of the basics of a typical test for electronics, and 3) We"ll conclude with the brief current status on progress.

  10. Review: laser ignition for aerospace propulsion

    Directory of Open Access Journals (Sweden)

    Steven A. O’Briant

    2016-03-01

    This paper aims to provide the reader an overview of advanced ignition methods, with an emphasis on laser ignition and its applications to aerospace propulsion. A comprehensive review of advanced ignition systems in aerospace applications is performed. This includes studies on gas turbine applications, ramjet and scramjet systems, and space and rocket applications. A brief overview of ignition and laser ignition phenomena is also provided in earlier sections of the report. Throughout the reading, research papers, which were presented at the 2nd Laser Ignition Conference in April 2014, are mentioned to indicate the vast array of projects that are currently being pursued.

  11. Damping in aerospace composite materials

    Science.gov (United States)

    Agneni, A.; Balis Crema, L.; Castellani, A.

    Experimental results are presented on specimens of carbon and Kevlar fibers in epoxy resin, materials used in many aerospace structures (control surfaces and wings in aircraft, large antennas in spacecraft, etc.). Some experimental methods of estimating damping ratios are first reviewed, either in the time domain or in the frequency domain. Some damping factor estimates from experimental tests are then shown; in order to evaluate the effects of the aerospace environment, damping factors have been obtained in a typical range of temperature, namely between +120 C and -120 C, and in the pressure range from room pressure to 10 exp -6 torr. Finally, a theoretical approach for predicting the bounds of the damping coefficients is shown, and prediction data are compared with experimental results.

  12. Design search and optimization in aerospace engineering.

    Science.gov (United States)

    Keane, A J; Scanlan, J P

    2007-10-15

    In this paper, we take a design-led perspective on the use of computational tools in the aerospace sector. We briefly review the current state-of-the-art in design search and optimization (DSO) as applied to problems from aerospace engineering, focusing on those problems that make heavy use of computational fluid dynamics (CFD). This ranges over issues of representation, optimization problem formulation and computational modelling. We then follow this with a multi-objective, multi-disciplinary example of DSO applied to civil aircraft wing design, an area where this kind of approach is becoming essential for companies to maintain their competitive edge. Our example considers the structure and weight of a transonic civil transport wing, its aerodynamic performance at cruise speed and its manufacturing costs. The goals are low drag and cost while holding weight and structural performance at acceptable levels. The constraints and performance metrics are modelled by a linked series of analysis codes, the most expensive of which is a CFD analysis of the aerodynamics using an Euler code with coupled boundary layer model. Structural strength and weight are assessed using semi-empirical schemes based on typical airframe company practice. Costing is carried out using a newly developed generative approach based on a hierarchical decomposition of the key structural elements of a typical machined and bolted wing-box assembly. To carry out the DSO process in the face of multiple competing goals, a recently developed multi-objective probability of improvement formulation is invoked along with stochastic process response surface models (Krigs). This approach both mitigates the significant run times involved in CFD computation and also provides an elegant way of balancing competing goals while still allowing the deployment of the whole range of single objective optimizers commonly available to design teams.

  13. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 49: Becoming an aerospace engineer: A cross-gender comparison

    Science.gov (United States)

    Hecht, Laura M.; Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1995-01-01

    We conducted a mail (self-reported) survey of 4300 student members of the American Institute of Aeronautics and Astronautics (AIAA) during the spring of 1993 as a Phase 3 activity of the NASA/DoD Aerospace Knowledge Diffusion Research Project. The survey was designed to explore students' career goals and aspirations, communications skills training, and their use of information sources, products, and services. We received 1723 completed questionnaires for an adjusted response rate of 42%. In this article, we compare the responses of female and male aerospace engineering students in the context of two general aspects of their educational experience. First, we explore the extent to which women and men differ in regard to factors that lead to the choice to study aerospace engineering, their current level of satisfaction with that choice, and their career-related goals and aspirations. Second, we examine students' responses to questions about communications skills training and the helpfulness of that training, and their use of and the importance to them of selected information sources, products, and services. The cross-gender comparison revealed more similarities than differences. Female students appear to be more satisfied than their male counterparts with the decision to major in aerospace engineering. Both female and male student respondents consider communications skills important for professional success, but females place a higher value than males do on oral communications skills. Women students also place a higher value than men do on the roles of other students and faculty members in satisfying their needs for information.

  14. In-service inspection guidelines for composite aerospace structures

    International Nuclear Information System (INIS)

    Heida, Jaap H.; Platenkamp, Derk J.

    2012-01-01

    The in-service inspection of composite aerospace structures is reviewed, using the results of a evaluation of promising, mobile non-destructive inspection (NDI) methods. The evaluation made use of carbon fibre reinforced specimens representative for primary composite aerospace structures, including relevant damage types such as impact damage, delaminations and disbonds. A range of NDI methods were evaluated such as visual inspection, vibration analysis, phased array ultrasonic inspection, shearography and thermography inspection. Important aspects of the evaluation were the capability for defect detection and characterization, portability of equipment, field of view, couplant requirements, speed of inspection, level of training required and the cost of equipment. The paper reviews the damage tolerance design approach for composites, and concludes with guidelines for the in-service inspection of composite aerospace structures.

  15. Fundamentals of Aerospace Engineering: An introductory course to aeronautical engineering

    OpenAIRE

    Soler, Manuel

    2014-01-01

    Fundamentals of Aerospace Engineering is a text book that provides an introductory, thorough overview of aeronautical engineering, and it is aimed at serving as reference for an undergraduate course on aerospace engineering.

  16. Critical comparison of hydrodynamic models for gas-solid fluidized beds - Part II: freely bubbling gas-solid fluidized beds

    NARCIS (Netherlands)

    Patil, D.J.; van Sint Annaland, M.; Kuipers, J.A.M.

    2005-01-01

    Correct prediction of spontaneous bubble formation in freely bubbling gas¿solid fluidized beds using Eulerian models, strongly depends on the description of the internal momentum transfer in the particulate phase. In this part, the comparison of the simple classical model, describing the solid phase

  17. Proposal for a EU quality label for aerospace education

    NARCIS (Netherlands)

    Bernelli-Zazzera, Franco; Angeles, Maria; Prats, Martin; Marulo, Francesco; Hanus, Daniel; Melkert, J.A.; Guglieri, Giorgio; Bauer, Pascal; Pantelaki, Irene; Wasser, Iring; Deconinck, Herman; Bosilca, Ruxandra; Saari, Hanna-Kaisa; Gherman, B.; Porumbel, I.

    2018-01-01

    The paper presents a possible roadmap for the definition of a European quality label for aerospace related higher education degrees. The proposal is the result of a two-years long Horizon 2020 project that has involved a great portion of the European stakeholders in aerospace: Universities, research

  18. International symposium on NDT in aerospace. Proceedings

    International Nuclear Information System (INIS)

    2008-01-01

    The emerging use of modern materials, especially in the aerospace industry, has initiated a new discussion about the current status and performance of Non Destructive Testing and Evaluation regarding their capability and reliability in material inspection and characterization. The substitution of mono materials, like aluminium, by composite materials, especially carbon fiber reinforced plastics, requires the development of advanced testing methods or even the combination of different methods. The symposium will bridge a gap between the different experts in NDT and E and will help to intensify the dialogue between basic NDT research and industrial NDT challenges. In April 2005 the project ''Development Center for Non-Destructive Testing of New Materials in Aerospace'' (''ZeLuR'') was authorized at the ''Technikum Neue Materialien'' in Fuerth. This project with a term of 4 years is funded by the Free State of Bavaria with the support of the Objective 2 Programme Bavaria 2002 - 2006 of the European Union. This project is addressing the various demands of different methods for the non-destructive testing of new materials in the aerospace industry. The sessions of the conference include thermal imaging, ultrasound technology, optics and all aspects of X-ray testing as well as structural health monitoring, reliability and adhesive bonding. Moreover the latest results of the project ''ZeLuR'' will be presented, covering various aspects of NDT in aerospace. (orig.)

  19. Inference-based procedural modeling of solids

    KAUST Repository

    Biggers, Keith; Keyser, John

    2011-01-01

    As virtual environments become larger and more complex, there is an increasing need for more automated construction algorithms to support the development process. We present an approach for modeling solids by combining prior examples with a simple

  20. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 18: A comparison of the technical communication practices of aerospace engineers and scientists in India and the United States

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1993-01-01

    As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communications practices of India and U.S. aerospace engineers and scientists. Both studies have the same seven objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communications to their profession; second, to determine the use and production of technical communications by aerospace engineers and scientists; third, to seek their views about the appropriate content of an undergraduate course in technical communications; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line data bases; fifth, to determine the use and importance of computer and information technology to them; sixth, to determine their use of electronic networks; and seventh, to determine their use of foreign and domestically produced technical reports. A self-administered questionnaire was distributed to aerospace engineers and scientists at the Indian Institute of Science and the NASA Langley Research Center. The completion rates for the India and U.S. surveys were 48 and 53 percent, respectively. Responses of the India and U.S. participants to selected questions are presented in this report.

  1. Research and Development of Rapid Design Systems for Aerospace Structure

    Science.gov (United States)

    Schaeffer, Harry G.

    1999-01-01

    This report describes the results of research activities associated with the development of rapid design systems for aerospace structures in support of the Intelligent Synthesis Environment (ISE). The specific subsystems investigated were the interface between model assembly and analysis; and, the high performance NASA GPS equation solver software system in the Windows NT environment on low cost high-performance PCs.

  2. CORBASec Used to Secure Distributed Aerospace Propulsion Simulations

    Science.gov (United States)

    Blaser, Tammy M.

    2003-01-01

    The NASA Glenn Research Center and its industry partners are developing a Common Object Request Broker (CORBA) Security (CORBASec) test bed to secure their distributed aerospace propulsion simulations. Glenn has been working with its aerospace propulsion industry partners to deploy the Numerical Propulsion System Simulation (NPSS) object-based technology. NPSS is a program focused on reducing the cost and time in developing aerospace propulsion engines. It was developed by Glenn and is being managed by the NASA Ames Research Center as the lead center reporting directly to NASA Headquarters' Aerospace Technology Enterprise. Glenn is an active domain member of the Object Management Group: an open membership, not-for-profit consortium that produces and manages computer industry specifications (i.e., CORBA) for interoperable enterprise applications. When NPSS is deployed, it will assemble a distributed aerospace propulsion simulation scenario from proprietary analytical CORBA servers and execute them with security afforded by the CORBASec implementation. The NPSS CORBASec test bed was initially developed with the TPBroker Security Service product (Hitachi Computer Products (America), Inc., Waltham, MA) using the Object Request Broker (ORB), which is based on the TPBroker Basic Object Adaptor, and using NPSS software across different firewall products. The test bed has been migrated to the Portable Object Adaptor architecture using the Hitachi Security Service product based on the VisiBroker 4.x ORB (Borland, Scotts Valley, CA) and on the Orbix 2000 ORB (Dublin, Ireland, with U.S. headquarters in Waltham, MA). Glenn, GE Aircraft Engines, and Pratt & Whitney Aircraft are the initial industry partners contributing to the NPSS CORBASec test bed. The test bed uses Security SecurID (RSA Security Inc., Bedford, MA) two-factor token-based authentication together with Hitachi Security Service digital-certificate-based authentication to validate the various NPSS users. The test

  3. An investigation of shape memory alloys as actuating elements in aerospace morphing applications

    DEFF Research Database (Denmark)

    Karagiannis, Dimitrios; Stamatelos, Dimtrios; Kappatos, Vasileios

    2017-01-01

    Two innovative actuating concepts for aerospace morphing applications, based on Shape Memory Alloys (SMAs), are proposed. The first concept investigates a composite plate incorporating embedded SMA wires. A Nonlinear Auto Regressive with eXogenous excitation (NARX) model is proposed for controlling...

  4. Aerospace Environmental Technology Conference: Exectutive summary

    Science.gov (United States)

    Whitaker, A. F. (Editor)

    1995-01-01

    The mandated elimination of CFC's, Halons, TCA, and other ozone depleting chemicals and specific hazardous materials has required changes and new developments in aerospace materials and processes. The aerospace industry has been involved for several years in providing product substitutions, redesigning entire production processes, and developing new materials that minimize or eliminate damage to the environment. These activities emphasize replacement cleaning solvents and their application verifications, compliant coatings including corrosion protection systems, and removal techniques, chemical propulsion effects on the environment, and the initiation of modifications to relevant processing and manufacturing specifications and standards. The papers from this conference are being published in a separate volume as NASA CP-3298.

  5. Output Feedback M-MRAC Backstepping With Aerospace Applications

    Science.gov (United States)

    Stepanyan, Vahram; Krishnakumar, Kalmanje Sriniva

    2014-01-01

    The paper presents a certainty equivalence output feedback backstepping adaptive control design method for the systems of any relative degree with unmatched uncertainties without over-parametrization. It uses a fast prediction model to estimate the unknown parameters, which is independent of the control design. It is shown that the system's input and output tracking errors can be systematically decreased by the proper choice of the design parameters. The approach is applied to aerospace control problems and tested in numerical simulations.

  6. Solid Waste Projection Model: Database (Version 1.3)

    International Nuclear Information System (INIS)

    Blackburn, C.L.

    1991-11-01

    The Solid Waste Projection Model (SWPM) system is an analytical tool developed by Pacific Northwest Laboratory (PNL) for Westinghouse Hanford Company (WHC). The SWPM system provides a modeling and analysis environment that supports decisions in the process of evaluating various solid waste management alternatives. This document, one of a series describing the SWPM system, contains detailed information regarding the software and data structures utilized in developing the SWPM Version 1.3 Database. This document is intended for use by experienced database specialists and supports database maintenance, utility development, and database enhancement

  7. International conference on Recent Advances in Aerospace Engineering (ICRAAE-2017)

    Science.gov (United States)

    2017-10-01

    Introduction The First International conference on Recent Advances in Aerospace Engineering (ICRAAE-2017) will be conducted by the Department of Aerospace Engineering at Karunya University, Coimbatore, Tamilnadu, India, on 3rd and 4th March, 2017. The conference aims to bring together students, academicians, leading scientists, researchers and industrialists working in diverse fields of Aerospace Engineering. This conference provides an inter-disciplinary platform for the educators, researchers and practitioners to present, share and discuss the recent trends, innovations, concerns and solutions in the cutting edge technologies of Aerospace Engineering for mutual benefit and the growth of the nation. Objectives The conference is devoted to benefit the participants who will have the opportunity to gain insight into state-of-the-art technologies in the field of Aerospace Engineering by the expert lectures of scientists and pioneering researchers from India and abroad. In addition, the two-day conference will enable knowledge sharing by personnel involved in active research working on the recent developments in this diverse field. List of International Deep Drawing Research Group, Conference Topics, Facts and Statistics, Achknowledgement, Keynote Speakers, Scientific Committee, Editors all are available in this PDF.

  8. A Thermodynamic Mixed-Solid Asphaltene Precipitation Model

    DEFF Research Database (Denmark)

    Lindeloff, Niels; Heidemann, R.A.; Andersen, Simon Ivar

    1998-01-01

    A simple model for the prediction of asphaltene precipitation is proposed. The model is based on an equation of state and uses standard thermodynamics, thus assuming that the precipitation phenomenon is a reversible process. The solid phase is treated as an ideal multicomponent mixture. An activity...

  9. Former Virginia Tech Aerospace and Ocean Engineering Department Head Dies

    OpenAIRE

    Gilbert, Karen

    2003-01-01

    James B. Eades, Jr., retired aerospace research scientist from Bluefield, W. Wa., and former professor and department head of aerospace and ocean engineering at Virginia Tech, died Dec. 14 at Veteran's Hospital in Washington, D.C. He was 80.

  10. Terrestrial Environment (Climatic) Criteria Guidelines for use in Aerospace Vehicle Development. 2008 Revision

    Science.gov (United States)

    Johnson, D. L. (Editor)

    2008-01-01

    This document provides guidelines for the terrestrial environment that are specifically applicable in the development of design requirements/specifications for NASA aerospace vehicles, payloads, and associated ground support equipment. The primary geographic areas encompassed are the John F. Kennedy Space Center, FL; Vandenberg AFB, CA; Edwards AFB, CA; Michoud Assembly Facility, New Orleans, LA; John C. Stennis Space Center, MS; Lyndon B. Johnson Space Center, Houston, TX; George C. Marshall Space Flight Center, Huntsville, AL; and the White Sands Missile Range, NM. This document presents the latest available information on the terrestrial environment applicable to the design and operations of aerospace vehicles and supersedes information presented in NASA-HDBK-1001 and TM X-64589, TM X-64757, TM-78118, TM-82473, and TM-4511. Information is included on winds, atmospheric thermodynamic models, radiation, humidity, precipitation, severe weather, sea state, lightning, atmospheric chemistry, seismic criteria, and a model to predict atmospheric dispersion of aerospace engine exhaust cloud rise and growth. In addition, a section has been included to provide information on the general distribution of natural environmental extremes in the conterminous United States, and world-wide, that may be needed to specify design criteria in the transportation of space vehicle subsystems and components. A section on atmospheric attenuation has been added since measurements by sensors on certain Earth orbital experiment missions are influenced by the Earth s atmosphere. There is also a section on mission analysis, prelaunch monitoring, and flight evaluation as related to the terrestrial environment inputs. The information in these guidelines is recommended for use in the development of aerospace vehicle and related equipment design and associated operational criteria, unless otherwise stated in contract work specifications. The terrestrial environmental data in these guidelines are

  11. Some problems in mechanics of growing solids with applications to AM technologies

    Science.gov (United States)

    Manzhirov, A. V.

    2018-04-01

    Additive Manufacturing (AM) technologies are an exciting area of the modern industrial revolution and have applications in engineering, medicine, electronics, aerospace industry, etc. AM enables cost-effective production of customized geometry and parts by direct fabrication from 3D data and mathematical models. Despite much progress in AM technologies, problems of mechanical analysis for AM fabricated parts yet remain to be solved. This paper deals with three main mechanical problems: the onset of residual stresses, which occur in the AM process and can lead to failure of the parts, the distortion of the final shape of AM fabricated parts, and the development of technological solutions aimed at improving existing AM technologies and creating new ones. An approach proposed deals with the construction of adequate analytical model and effective methods for the simulation of AM processes for fabricated solid parts.

  12. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 52: A comparison of the technical communications practices of Japanese and US aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Holloway, Karen; Sato, Yuko; Barclay, Rebecca O.; Kennedy, John M.

    1995-01-01

    To understand the diffusion of aerospace knowledge, it is necessary to understand the communications practices and the information-seeking behaviors of those involved in the production, transfer, and use of aerospace knowledge at the individual, organizational, national, and international levels. In this paper, we report selected results from a survey of Japanese and U.S. aerospace engineers and scientists that focused on communications practices and information-seeking behaviors in the workplace. Data are presented for the following topics: importance of and time spent communicating information, collaborative writing, need for an undergraduate course in technical communications, use of libraries, the use and importance of electronic (computer) networks, and the use and importance of foreign and domestically produced technical reports. The responses of the survey respondents are placed within the context of the Japanese culture. We assume that differences in Japanese and U.S. cultures influence the communications practices and information-seeking behaviors of Japanese and U.S. aerospace engineers and scientists.

  13. Modelling Gas Adsorption in Porous Solids: Roles of Surface ...

    Indian Academy of Sciences (India)

    Modelling the adsorption of small molecule gases such as N2, CH4 and CO2 in porous solids can ... fusive properties of CO2 adsorbed in the solids have been examined using ..... exhibit a wide range of physical behavior.78,79 The intro-.

  14. KIBO Industry, innovates in aerospace

    Science.gov (United States)

    Paillard, Jean-Philippe

    2016-07-01

    The conquest of space is a true inspiration. Imagine a long-duration mission to a distant destination. What shall we take to produce our food? A cow, fish, chicken, or just eggs. In the current state of the animal production technologies are complicated and expensive to implement, except perhaps one: the breeding of edible insects. Based on this postulate KIBO in partnership with Space Agriculture Task Force and the university's department of Nutrition Nagoya most innovative research program is created in modern nutrition. This program is called Pegasus. Pegasus research program aims to develop food productions and modules applicable to the aerospace conquest. Kibo industry is the first entomocole production company creat in Europe to human food; it aims to become the world leader by 2020. Kibo industry is particularly specialized in producing entomosource (products with insects). The first phase of the program is to achieve an outcome cereal bar edible insect to aerospace. So we will present the issues and objectives of the project, for aerospace and us. Jean-Philippe Paillard is the KIBO industry CEO and Vice President of the FFPIDI insects farms federation. He is also the co computer alone authorization dossier on the market in Europe and therefore the privileged interlocutor of the General Directorate for Health and Customer Review on this topic. He intervened at the last conference on the insect organized by FAO in Wageningen and various universities in France.

  15. Economic interrelationships and impacts of the aviation/aerospace industry in the state of Florida using input-output analysis

    Science.gov (United States)

    Whealan George, Kelly

    positive indirect and induced effect in the economy providing almost a two-fold indirect and induced effect. However, the benefits were not equal. Florida's average labor income of the most sensitive non-aviation and aerospace industry was 15% lower than the average Florida labor income. The average labor income in VC of the most sensitive non-aviation and aerospace industry was significantly higher than the average VC labor income. Industry interdependencies also presented risk. If the aviation and aerospace industry experiences a contraction, then through the interdependencies of the industries, the region would contract twice as much as the aviation and aerospace industry. The overall impact of a university research park would benefit Florida's economy. Since the research park project is currently funded partially by public state money, 14 sectors of the economy experienced negative impacts. While the net result was an increase in additional labor income, the employment growth was characterized by gaining more lower-paying jobs while losing less higher-paying jobs. The most expected outcome, an expansion of the aviation and aerospace industry, was not evidenced by the model results.

  16. An historical summary of advisory boards for aerospace medicine at NASA.

    Science.gov (United States)

    Doarn, Charles R

    2013-03-01

    Over the past 50 years, the National Aeronautics and Space Administration (NASA) has interacted with numerous advisory committees. These committees include those established by NASA, the National Academy of Sciences, the Institute of Medicine, or through Congressional oversight. Such groups have had a relatively passive role while providing sage advice on a variety of important issues. While these groups cover a wide range of disciplines, the focus of this paper is on those that impacted aerospace medicine and human spaceflight from NASA's beginning to the present time. The intent is to provide an historical narrative of the committees, their purpose, their outcome, and how they influenced the development of aerospace medicine within NASA. Aerospace medicine and life sciences have been closely aligned and intertwined from NASA's beginning. While several committees overlap life sciences within NASA, life sciences will not be presented unless it is in direct reference to aerospace medicine. This paper provides an historical summary chronicling those individuals and the groups they led when aerospace medicine was emerging as a discipline for human spaceflight beginning in 1957.

  17. Kinetic Monte Carlo simulation of three-dimensional shape evolution with void formation using Solid-by-Solid model: Application to via and trench filling

    International Nuclear Information System (INIS)

    Kaneko, Yutaka; Hiwatari, Yasuaki; Ohara, Katsuhiko; Asa, Fujio

    2013-01-01

    In this paper we present the Kinetic Monte Carlo simulation system for the simulation of three-dimensional shape evolution with void formation as a model for electrodeposition. The basic system is the Solid-by-Solid model which is an extension of the conventional Solid-on-Solid model for crystal growth to include void formation. The advantage of the Solid-by-Solid model is that complex three-dimensional shape evolution accompanying void formation (from point defects to macro voids) can be simulated without the difficulty of treating moving boundaries. This model has been extended to include the solution part in which the migration of ions is simulated by the coarse-grained random walk. A multi-scale method is employed to generate the concentration gradient in the diffusion layer. The extended model is applied to the simulation of via and trench fillings by copper electrodeposition. Three kinds of additives are included: suppressors, accelerators and chloride ions. The mechanism of void formation, effects of additives and their influence on the bottom-up filling are discussed within the framework of this model

  18. Developing a Current Capability Design for Manufacture Framework in the Aerospace Industry

    OpenAIRE

    Whiteside, A.; Shehab, Essam; Beadle, C.; Percival, M.

    2009-01-01

    Organised by: Cranfield University During progressive product design and development in the aerospace industry, a lack of effective communication between the sequential functions of design, manufacturing and assembly often causes delays and setbacks whereby production capabilities are unable to realise design intent in high-complexity product models. As a result, there is a need to formalise the progressive release of an engineering model to production functions during New Prod...

  19. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 28: The technical communication practices of aerospace engineering and science students: Results of the phase 4 cross-national surveys

    Science.gov (United States)

    Pinelli, Thomas E.; Hecht, Laura M.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    This report describes similarities and differences between undergraduate and graduate aerospace engineering and science students in the context of two general aspects of the educational experience. First, we explore the extent to which students differ regarding the factors that lead to the choice of becoming an aerospace engineer or a scientist, current satisfaction with that choice, and career-related goals and objectives. Second, we look at the technical communication skills, practices, habits, and training of aerospace engineering and science students. The reported data were obtained from a survey of students enrolled in aerospace engineering and science programs at universities in India, Japan, Russia, and the United Kingdom. The surveys were undertaken as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. Data are reported for the following categories: student demographics; skill importance, skill training, and skill helpfulness; collaborative writing; computer and information technology use and importance, use of electronic networks; use and importance of libraries and library services; use and importance of information sources and products; use of foreign language technical reports; and foreign language (reading and speaking) skills.

  20. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 20: Engineers as information processors: A survey of US aerospace engineering faculty and students

    Science.gov (United States)

    Holland, Maurita Peterson; Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1991-01-01

    U.S. aerospace engineering faculty and students were surveyed as part of the NASA/DoD Aerospace Knowledge Research Project. Faculty and students were viewed as information processors within a conceptual framework of information seeking behavior. Questionnaires were received from 275 faculty members and 640 students, which were used to determine: (1) use and importance of information sources; (2) use of specific print sources and electronic data bases; (3) use of information technology; and (4) the influence of instruction on the use of information sources and the products of faculty and students. Little evidence was found to support the belief that instruction in library or engineering information use has significant impact either on broadening the frequency or range of information products and sources used by U.S. aerospace engineering students.

  1. Sintered Cathodes for All-Solid-State Structural Lithium-Ion Batteries

    Science.gov (United States)

    Huddleston, William; Dynys, Frederick; Sehirlioglu, Alp

    2017-01-01

    All-solid-state structural lithium ion batteries serve as both structural load-bearing components and as electrical energy storage devices to achieve system level weight savings in aerospace and other transportation applications. This multifunctional design goal is critical for the realization of next generation hybrid or all-electric propulsion systems. Additionally, transitioning to solid state technology improves upon battery safety from previous volatile architectures. This research established baseline solid state processing conditions and performance benchmarks for intercalation-type layered oxide materials for multifunctional application. Under consideration were lithium cobalt oxide and lithium nickel manganese cobalt oxide. Pertinent characteristics such as electrical conductivity, strength, chemical stability, and microstructure were characterized for future application in all-solid-state structural battery cathodes. The study includes characterization by XRD, ICP, SEM, ring-on-ring mechanical testing, and electrical impedance spectroscopy to elucidate optimal processing parameters, material characteristics, and multifunctional performance benchmarks. These findings provide initial conditions for implementing existing cathode materials in load bearing applications.

  2. The need for the solid modelling of structure in the archaeology of buildings

    Directory of Open Access Journals (Sweden)

    Robert Daniels

    1997-03-01

    Full Text Available Three-dimensional modelling is an attempt to represent the world in three dimensions, simplifying through deliberate assumptions. In archaeology, this has developed as an extension of the traditional use of three-dimensional drawings to help present and record data. The debate in the archaeological literature over whether surface or solid modellers should be used is one based on the premise that the purpose of three-dimensional modelling is data visualisation. This concentration on perception modelling has been at the expense of research on the modelling of structure. Surface and Solid Modellers are introduced and defined. I argue that developments in modelling software mean that there is no longer a clear distinction between the two types of software along application lines. We should think of models in terms of their applications rather than the software which generates them. Although data visualisation (including virtual reality is an important part of three-dimensional modelling, I argue that it should be explicitly divorced from the related field of photo-realism at a research level. Perception modelling can be performed by surface or solid modellers. Modelling structure is better performed with a solid modeller, if we wish to be as explicit as possible in our modelling. A structural model can be used as a spatial database. If we wish to ask questions about the physical properties of a structure, then we must use solid modellers. In addition to the engineering properties of structures, solid modellers can also be used to answer questions about the economics of construction. For historical reasons, the construction industry has preferred to use surface modellers, but I argue for the advantages of solid modelling in the archaeological study of construction.

  3. A model based bayesian solution for characterization of complex damage scenarios in aerospace composite structures.

    Science.gov (United States)

    Reed, H; Leckey, Cara A C; Dick, A; Harvey, G; Dobson, J

    2018-01-01

    Ultrasonic damage detection and characterization is commonly used in nondestructive evaluation (NDE) of aerospace composite components. In recent years there has been an increased development of guided wave based methods. In real materials and structures, these dispersive waves result in complicated behavior in the presence of complex damage scenarios. Model-based characterization methods utilize accurate three dimensional finite element models (FEMs) of guided wave interaction with realistic damage scenarios to aid in defect identification and classification. This work describes an inverse solution for realistic composite damage characterization by comparing the wavenumber-frequency spectra of experimental and simulated ultrasonic inspections. The composite laminate material properties are first verified through a Bayesian solution (Markov chain Monte Carlo), enabling uncertainty quantification surrounding the characterization. A study is undertaken to assess the efficacy of the proposed damage model and comparative metrics between the experimental and simulated output. The FEM is then parameterized with a damage model capable of describing the typical complex damage created by impact events in composites. The damage is characterized through a transdimensional Markov chain Monte Carlo solution, enabling a flexible damage model capable of adapting to the complex damage geometry investigated here. The posterior probability distributions of the individual delamination petals as well as the overall envelope of the damage site are determined. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. A thermodynamic model for solid solutions and its application to the C-Fe-Co, C-Fe-Ni and Mn-Cr-Pt solid dilutions

    International Nuclear Information System (INIS)

    Tao, D.P.

    2004-01-01

    Based on the free volume theory and the lattice model, the partition functions of pure solids and their mixtures were expressed. This resulted in the establishment of a thermodynamic model for solid solutions. The model naturally combines the excess entropy and excess enthalpy of a solution by means of new expressions of the configurational partition functions of solids and their mixtures derived from statistical thermodynamics, which is approximate to real solid solutions, that is S E ≠0 (V E ≠0) and H E ≠0. It can describe the thermodynamic properties of partially miscible systems and predict the thermodynamic properties in a multicomponent solid solution system using only the related binary infinite dilute activity coefficients. The predicted activity coefficients from the model are in good agreement with the experimental data of the ternary solid dilutions. This shows that the prediction effect of the proposed model is of better stability and reliability because it has a good physical basis

  5. Surface effects in solid mechanics models, simulations and applications

    CERN Document Server

    Altenbach, Holm

    2013-01-01

    This book reviews current understanding, and future trends, of surface effects in solid mechanics. Covers elasticity, plasticity and viscoelasticity, modeling based on continuum theories and molecular modeling and applications of different modeling approaches.

  6. 75 FR 57844 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Science.gov (United States)

    2010-09-23

    ... Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft... Previously Held by Israel Aircraft Industries, Ltd.): Amendment 39-16438. Docket No. FAA-2010-0555... (Type Certificate previously held by Israel Aircraft Industries, Ltd.) Model Galaxy and Gulfstream 200...

  7. The Relationship of Skilled Aerospace Manufacturing Workforce Performance to Training

    Science.gov (United States)

    Malsberry, Suzanne

    2014-01-01

    A major economic driver, the aerospace industry contributes to exports and higher wage jobs, which the United States requires to maintain robust economic health. Despite the investment in vocational educational training programs, insufficient workers have been available to aerospace companies. The purpose of this study was to investigate the…

  8. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 36: Technical uncertainty as a correlate of information use by US industry-affiliated aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Glassman, Nanci A.; Affelder, Linda O.; Hecht, Laura M.; Kennedy, John M.; Barclay, Rebecca O.

    1994-01-01

    This paper reports the results of an exploratory study that investigated the influence of technical uncertainty on the use of information and information sources by U.S. industry-affiliated aerospace engineers and scientists in completing or solving a project, task, or problem. Data were collected through a self-administered questionnaire. Survey participants were U.S. aerospace engineers and scientists whose names appeared on the Society of Automotive Engineers (SAE) mailing list. The results support the findings of previous research and the following study assumptions. Information and information-source use differ for projects, problems, and tasks with high and low technical uncertainty. As technical uncertainty increases, information-source use changes from internal to external and from informal to formal sources. As technical uncertainty increases, so too does the use of federally funded aerospace research and development (R&D). The use of formal information sources to learn about federally funded aerospace R&D differs for projects, problems, and tasks with high and low technical uncertainty.

  9. Aerospace gerontology

    Science.gov (United States)

    Comfort, A.

    1982-01-01

    The relevancy of gerontology and geriatrics to the discipline of aerospace medicine is examined. It is noted that since the shuttle program gives the facility to fly passengers, including specially qualified older persons, it is essential to examine response to acceleration, weightlessness, and re-entry over the whole adult lifespan, not only its second quartile. The physiological responses of the older person to weightlessness and the return to Earth gravity are reviewed. The importance of the use of the weightless environment to solve critical problems in the fields of fundamental gerontology and geriatrics is also stressed.

  10. Computational simulation of coupled material degradation processes for probabilistic lifetime strength of aerospace materials

    Science.gov (United States)

    Boyce, Lola; Bast, Callie C.

    1992-01-01

    The research included ongoing development of methodology that provides probabilistic lifetime strength of aerospace materials via computational simulation. A probabilistic material strength degradation model, in the form of a randomized multifactor interaction equation, is postulated for strength degradation of structural components of aerospace propulsion systems subjected to a number of effects or primative variables. These primative variable may include high temperature, fatigue or creep. In most cases, strength is reduced as a result of the action of a variable. This multifactor interaction strength degradation equation has been randomized and is included in the computer program, PROMISS. Also included in the research is the development of methodology to calibrate the above described constitutive equation using actual experimental materials data together with linear regression of that data, thereby predicting values for the empirical material constraints for each effect or primative variable. This regression methodology is included in the computer program, PROMISC. Actual experimental materials data were obtained from the open literature for materials typically of interest to those studying aerospace propulsion system components. Material data for Inconel 718 was analyzed using the developed methodology.

  11. Characterizing Distributed Concurrent Engineering Teams: A Descriptive Framework for Aerospace Concurrent Engineering Design Teams

    Science.gov (United States)

    Chattopadhyay, Debarati; Hihn, Jairus; Warfield, Keith

    2011-01-01

    As aerospace missions grow larger and more technically complex in the face of ever tighter budgets, it will become increasingly important to use concurrent engineering methods in the development of early conceptual designs because of their ability to facilitate rapid assessments and trades in a cost-efficient manner. To successfully accomplish these complex missions with limited funding, it is also essential to effectively leverage the strengths of individuals and teams across government, industry, academia, and international agencies by increased cooperation between organizations. As a result, the existing concurrent engineering teams will need to increasingly engage in distributed collaborative concurrent design. This paper is an extension of a recent white paper written by the Concurrent Engineering Working Group, which details the unique challenges of distributed collaborative concurrent engineering. This paper includes a short history of aerospace concurrent engineering, and defines the terms 'concurrent', 'collaborative' and 'distributed' in the context of aerospace concurrent engineering. In addition, a model for the levels of complexity of concurrent engineering teams is presented to provide a way to conceptualize information and data flow within these types of teams.

  12. The potential advantages of microstructure modeling of titanium to the aerospace industry

    International Nuclear Information System (INIS)

    Boyer, R.R.; Furrer, D.U.

    2004-01-01

    A multi-organization team across the entire titanium aerospace supply chain has been established to develop and implement modeling tools for the reduction of manufacturing lead-time and cost. This Air Force sponsored Metals Affordability Initiative (MAI) program is developing model tools capable of predicting the microstructure and mechanical properties of titanium alloys. The developed tools are intended to enable predicting the microstructure and texture evolution through wrought processing and heat treatment of ingot metallurgy titanium components, with a stronger emphasis on the latter stages of the processing. It will also take into account chemistry, including the composition of the individual phases during processing. Beta phase and primary alpha phase grain growth at temperature and during cooling along with morphological aspects will be taken into consideration.The success of this modeling effort could have a significant impact on the industry in terms of reducing cost and lead times of wrought products -- while this study is directed at forgings, there is no reason it would not be applicable to other product forms. Initial applications of these tools include the potential to reduce and in some cases eliminate certification testing presently done on forged or other components. There is also the potential for making a disposition on components with a metallurgical discrepancy without cutting up (sacrificing) a part(s), through the use of predictive tools. For parts where the property requirements are difficult to meet, these modeling tools could also enable one to determine the more critical parameters and concentrate efforts on controlling them, providing a more consistent product.In the longer term, titanium modeling tools could result in reduction of the lead time and cost of developing a new heat treatment or alloy to meet specific application requirements -- the models could be used to predict the proper aim chemistry, optimized chemistry limits, and

  13. Study of combined cycle engine for aerospace plane

    OpenAIRE

    苅田, 丈士; KANDA, Takeshi; 工藤, 賢司; KUDO, Kenji

    2002-01-01

    At the Ramjet Propulsion Research Center, the scramjet engine for an aerospace plane has been studied. Other engines are required for the plane to go into orbit. Recently, a combined cycle engine including scramjet mode has been also studied to complete the engine system for the plane. The scramjet and the combined cycle engine are most effective with application to the Single-Stage-to-Orbit (SSTO) aerospace plane, as shown in Figure 1. Recent activity on the combined cycle engine and the SST...

  14. Automation technology for aerospace power management

    Science.gov (United States)

    Larsen, R. L.

    1982-01-01

    The growing size and complexity of spacecraft power systems coupled with limited space/ground communications necessitate increasingly automated onboard control systems. Research in computer science, particularly artificial intelligence has developed methods and techniques for constructing man-machine systems with problem-solving expertise in limited domains which may contribute to the automation of power systems. Since these systems perform tasks which are typically performed by human experts they have become known as Expert Systems. A review of the current state of the art in expert systems technology is presented, and potential applications in power systems management are considered. It is concluded that expert systems appear to have significant potential for improving the productivity of operations personnel in aerospace applications, and in automating the control of many aerospace systems.

  15. 5th Conference on Aerospace Materials, Processes, and Environmental Technology

    Science.gov (United States)

    Cook, M. B. (Editor); Stanley, D. Cross (Editor)

    2003-01-01

    Records are presented from the 5th Conference on Aerospace Materials, Processes, and Environmental Technology. Topics included pollution prevention, inspection methods, advanced materials, aerospace materials and technical standards,materials testing and evaluation, advanced manufacturing,development in metallic processes, synthesis of nanomaterials, composite cryotank processing, environmentally friendly cleaning, and poster sessions.

  16. Aerospace Technology Curriculum Guide. Invest in Success. Vo. Ed. #260.

    Science.gov (United States)

    Idaho State Dept. of Education, Boise. Div. of Vocational Education.

    This document contains standards for an articulated secondary and postsecondary curriculum in aerospace technology. The curriculum standards can be used to ensure that vocational programs meet the needs of local business and industry. The first part of the document contains a task list and student performance standards for the aerospace technology…

  17. Numerical modelling of biomass combustion: Solid conversion processes in a fixed bed furnace

    Science.gov (United States)

    Karim, Md. Rezwanul; Naser, Jamal

    2017-06-01

    Increasing demand for energy and rising concerns over global warming has urged the use of renewable energy sources to carry a sustainable development of the world. Bio mass is a renewable energy which has become an important fuel to produce thermal energy or electricity. It is an eco-friendly source of energy as it reduces carbon dioxide emissions. Combustion of solid biomass is a complex phenomenon due to its large varieties and physical structures. Among various systems, fixed bed combustion is the most commonly used technique for thermal conversion of solid biomass. But inadequate knowledge on complex solid conversion processes has limited the development of such combustion system. Numerical modelling of this combustion system has some advantages over experimental analysis. Many important system parameters (e.g. temperature, density, solid fraction) can be estimated inside the entire domain under different working conditions. In this work, a complete numerical model is used for solid conversion processes of biomass combustion in a fixed bed furnace. The combustion system is divided in to solid and gas phase. This model includes several sub models to characterize the solid phase of the combustion with several variables. User defined subroutines are used to introduce solid phase variables in commercial CFD code. Gas phase of combustion is resolved using built-in module of CFD code. Heat transfer model is modified to predict the temperature of solid and gas phases with special radiation heat transfer solution for considering the high absorptivity of the medium. Considering all solid conversion processes the solid phase variables are evaluated. Results obtained are discussed with reference from an experimental burner.

  18. An Aerospace Nation

    Science.gov (United States)

    2016-05-25

    of world commerce , informa- tion, and finance. Its education system was second to none, and its cur- rency was the world’s benchmark. In the early...professionals than the United States. An estimate by the US Department of Commerce predicts that by 2018 “the U.S. will have more than 1.2 million unfilled...taxpayer.30 Thus, being an advanced aerospace nation will help balance the federal budget and extend the benefits of prosperity to a new generation

  19. Modeling of urban solid waste management system: The case of Dhaka city

    International Nuclear Information System (INIS)

    Sufian, M.A.; Bala, B.K.

    2007-01-01

    This paper presents a system dynamics computer model to predict solid waste generation, collection capacity and electricity generation from solid waste and to assess the needs for waste management of the urban city of Dhaka, Bangladesh. Simulated results show that solid waste generation, collection capacity and electricity generation potential from solid waste increase with time. Population, uncleared waste, untreated waste, composite index and public concern are projected to increase with time for Dhaka city. Simulated results also show that increasing the budget for collection capacity alone does not improve environmental quality; rather an increased budget is required for both collection and treatment of solid wastes of Dhaka city. Finally, this model can be used as a computer laboratory for urban solid waste management (USWM) policy analysis

  20. Modeling of urban solid waste management system: the case of Dhaka city

    International Nuclear Information System (INIS)

    Sufian, M.A.; Bala, B.K.

    2005-01-01

    This paper presents a system dynamics computer model to predict solid waste generation, collection capacity and electricity generation from solid waste and to assess the needs for waste management of the urban city Dhaka Bangladesh. Simulated results show that solid waste generation, collection capacity and electricity generation potential from solid waste increase with time. Population, uncleared waste, untreated waste, composite index and public concern are increasing with time for Dhaka city. Simulated results also show that increasing the budge for collection capacity alone does not improve the environmental quality rather increased budget is required for both collection and treatment of solid wastes of Dhaka city. Finally, this model can be used as a compute laboratory for urban solid waste management (USWM) policy analysis. (author)

  1. Cell-model prediction of the melting of a Lennard-Jones solid

    International Nuclear Information System (INIS)

    Holian, B.L.

    1980-01-01

    The classical free energy of the Lennard-Jones 6-12 solid is computed from a single-particle anharmonic cell model with a correction to the entropy given by the classical correlational entropy of quasiharmonic lattice dynamics. The free energy of the fluid is obtained from the Hansen-Ree analytic fit to Monte Carlo equation-of-state calculations. The resulting predictions of the solid-fluid coexistence curves by this corrected cell model of the solid are in excellent agreement with the computer experiments

  2. Aerospace toxicology overview: aerial application and cabin air quality.

    Science.gov (United States)

    Chaturvedi, Arvind K

    2011-01-01

    Aerospace toxicology is a rather recent development and is closely related to aerospace medicine. Aerospace toxicology can be defined as a field of study designed to address the adverse effects of medications, chemicals, and contaminants on humans who fly within or outside the atmosphere in aviation or on space flights. The environment extending above and beyond the surface of the Earth is referred to as aerospace. The term aviation is frequently used interchangeably with aerospace. The focus of the literature review performed to prepare this paper was on aerospace toxicology-related subject matters, aerial application and aircraft cabin air quality. Among the important topics addressed are the following: · Aerial applications of agricultural chemicals, pesticidal toxicity, and exposures to aerially applied mixtures of chemicals and their associated formulating solvents/surfactants The safety of aerially encountered chemicals and the bioanalytical methods used to monitor exposures to some of them · The presence of fumes and smoke, as well as other contaminants that may generally be present in aircraft/space vehicle cabin air · And importantly, the toxic effects of aerially encountered contaminants, with emphasis on the degradation products of oils, fluids, and lubricants used in aircraft, and finally · Analytical methods used for monitoring human exposure to CO and HCN are addressed in the review, as are the signs and symptoms associated with exposures to these combustion gases. Although many agricultural chemical monitoring studies have been published, few have dealt with the occurrence of such chemicals in aircraft cabin air. However, agricultural chemicals do appear in cabin air; indeed, attempts have been made to establish maximum allowable concentrations for several of the more potentially toxic ones that are found in aircraft cabin air. In this article, I emphasize the need for precautionary measures to be taken to minimize exposures to aerially

  3. Molecular Modeling of Aerospace Polymer Matrices Including Carbon Nanotube-Enhanced Epoxy

    Science.gov (United States)

    Radue, Matthew S.

    Carbon fiber (CF) composites are increasingly replacing metals used in major structural parts of aircraft, spacecraft, and automobiles. The current limitations of carbon fiber composites are addressed through computational material design by modeling the salient aerospace matrix materials. Molecular Dynamics (MD) models of epoxies with and without carbon nanotube (CNT) reinforcement and models of pure bismaleimides (BMIs) were developed to elucidate structure-property relationships for improved selection and tailoring of matrices. The influence of monomer functionality on the mechanical properties of epoxies is studied using the Reax Force Field (ReaxFF). From deformation simulations, the Young's modulus, yield point, and Poisson's ratio are calculated and analyzed. The results demonstrate an increase in stiffness and yield strength with increasing resin functionality. Comparison between the network structures of distinct epoxies is further advanced by the Monomeric Degree Index (MDI). Experimental validation demonstrates the MD results correctly predict the relationship in Young's moduli for all epoxies modeled. Therefore, the ReaxFF is confirmed to be a useful tool for studying the mechanical behavior of epoxies. While epoxies have been well-studied using MD, there has been no concerted effort to model cured BMI polymers due to the complexity of the network-forming reactions. A novel, adaptable crosslinking framework is developed for implementing 5 distinct cure reactions of Matrimid-5292 (a BMI resin) and investigating the network structure using MD simulations. The influence of different cure reactions and extent of curing are analyzed on the several thermo-mechanical properties such as mass density, glass transition temperature, coefficient of thermal expansion, elastic moduli, and thermal conductivity. The developed crosslinked models correctly predict experimentally observed trends for various properties. Finally, the epoxies modeled (di-, tri-, and tetra

  4. Between Industry and Academia: A Physicist's Experiences at The Aerospace Corporation

    Science.gov (United States)

    Camparo, James

    2005-03-01

    The Aerospace Corporation is a nonprofit company whose purposes are exclusively scientific: to provide research, development, and advisory services for space programs that serve the national interest, primarily the Air Force's Space and Missile Systems Center and the National Reconnaissance Office. The corporation's laboratory has a staff of about 150 scientists who conduct research in fields ranging from Space Sciences to Material Sciences and from Analytical Chemistry to Atomic Physics. As a consequence, Aerospace stands midway between an industrial research laboratory, focused on product development, and academic/national laboratories focused on basic science. Drawing from Dr. Camparo's personal experiences, the presentation will discuss advantages and disadvantages of a career at Aerospace, including the role of publishing in peer-reviewed journals and the impact of work on family life. Additionally, the presentation will consider the balance between basic physics, applied physics, and engineering in the work at Aerospace. Since joining Aerospace in 1981, Dr. Camparo has worked as an atomic physicist specializing in the area of atomic clocks, and has had the opportunity to experiment and publish on a broad range of research topics including: the stochastic-field/atom interaction, radiation effects on semiconductor materials, and stellar scintillation.

  5. PREFACE: Trends in Aerospace Manufacturing 2009 International Conference

    Science.gov (United States)

    Ridgway, Keith; Gault, Rosemary; Allen, Adrian

    2011-12-01

    The aerospace industry is rapidly changing. New aircraft structures are being developed and aero-engines are becoming lighter and more environmentally friendly. In both areas, innovative materials and manufacturing methods are used in an attempt to get maximum performance for minimum cost. At the same time, the structure of the industry has changed and there has been a move from large companies designing, manufacturing components and assembling aircraft to one of large global supply chains headed by large system integrators. All these changes have forced engineers and managers to bring in innovations in design, materials, manufacturing technologies and supply chain management. In September 2009, the Advanced Manufacturing Research Centre (AMRC) at the University of Sheffield held the inaugural Trends in Aerospace Manufacturing conference (TRAM09). This brought together 28 speakers over two days, who presented in sessions on advanced manufacturing trends for the aerospace sector. Areas covered included new materials, including composites, advanced machining, state of the art additive manufacturing techniques, assembly and supply chain issues.

  6. A Model of the Effect of the Microbial Biomass on the Isotherm of the Fermenting Solids in Solid-State Fermentation

    Directory of Open Access Journals (Sweden)

    Barbara Celuppi Marques

    2006-01-01

    Full Text Available We compare isotherms for soybeans and soybeans fermented with Rhizopus oryzae, showing that in solid-state fermentation the biomass affects the isotherm of the fermenting solids. Equations are developed to calculate, for a given overall water content of the fermenting solids, the water contents of the biomass and residual substrate, as well as the water activity. A case study, undertaken using a mathematical model of a well-mixed bioreactor, shows that if water additions are made on the basis of the assumption that fermenting solids have the same isotherm as the substrate itself, poor growth can result since the added water does not maintain the water activity at levels favorable for growth. We conclude that the effect of the microbial biomass on the isotherm of the fermenting solids must be taken into account in mathematical models of solid-state fermentation bioreactors.

  7. Appraisal of New Product Development Success Indicators in the Aerospace Industry

    DEFF Research Database (Denmark)

    Kazerouni, Afrooz Moatari; Achiche, Sofiane; Hisarciklilar, Onur

    2011-01-01

    , different metrics need to be used at different phases of the product lifecycle (PLC). This paper describes the research undertaken to determine success measurement metrics for new product development (NPD) processes. The goal of this research was to ascertain an appropriate set of metrics used by aerospace...... companies for assessing success during different phases of the PLC. Furthermore, an evaluation of the differences and similarities of NPD success measurement was carried out between aerospace companies and the non-aerospace companies practicing in the business-to-business (B2B) market. Practical case......) the measurement of success of aerospace NPD practices depends on the PLC phase being measured, 2) product and process management performance are the more important indicators of success in the early PLC phases with revenue and market share indicators being important during late phases, 3) there are reasonable...

  8. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 15: Technical uncertainty and project complexity as correlates of information use by US industry-affiliated aerospace engineers and scientists: Results of an exploratory investigation

    Science.gov (United States)

    Pinelli, Thomas E.; Glassman, Nanci A.; Affelder, Linda O.; Hecht, Laura M.; Kennedy, John M.; Barclay, Rebecca O.

    1993-01-01

    An exploratory study was conducted that investigated the influence of technical uncertainty and project complexity on information use by U.S. industry-affiliated aerospace engineers and scientists. The study utilized survey research in the form of a self-administered mail questionnaire. U.S. aerospace engineers and scientists on the Society of Automotive Engineers (SAE) mailing list served as the study population. The adjusted response rate was 67 percent. The survey instrument is appendix C to this report. Statistically significant relationships were found to exist between technical uncertainty, project complexity, and information use. Statistically significant relationships were found to exist between technical uncertainty, project complexity, and the use of federally funded aerospace R&D. The results of this investigation are relevant to researchers investigating information-seeking behavior of aerospace engineers. They are also relevant to R&D managers and policy planners concerned with transferring the results of federally funded aerospace R&D to the U.S. aerospace industry.

  9. Mechanical performances of lead-free solder joint connections with applications in the aerospace domain

    Directory of Open Access Journals (Sweden)

    Georgiana PADURARU

    2016-03-01

    Full Text Available The paper presents some theoretical and experimental aspects regarding the tribological performances of lead-free solder joint connections, with application in the aerospace domain. In order to highlight the mechanical and tribological properties of solder joint in correlation with different pad finishes, there were made some mechanical determinations using a dedicated Share Test System. The theoretical model highlights the link between the experimental results and the influence of gravitational acceleration on the mechanical and functional integrity of the electronic assemblies that works in vibration environment. The paper novelty is provided by the interdisciplinary experiment that offers results that can be used in the mechanical, tribological, electronical and aerospace domains.

  10. Nanomaterials: Opportunities and Challenges for Aerospace

    National Research Council Canada - National Science Library

    Obieta, Isabel; Marcos, J

    2005-01-01

    Nanomaterials are regarded world-wide as key materials of the 21st Century. Also, in aerospace a high potential for nanomaterials applications is postulated and technological breakthroughs are expected in this area...

  11. Modeling steel deformation in the semi-solid state

    CERN Document Server

    Hojny, Marcin

    2017-01-01

    This book addresses selected aspects of steel-deformation modelling, both at very high temperatures and under the conditions in which the liquid and the solid phases coexist. Steel-deformation modelling with its simultaneous solidification is particularly difficult due to its specificity and complexity. With regard to industrial applications and the development of new, integrated continuous casting and rolling processes, the issues related to modelling are becoming increasingly important. Since the numerous industrial tests that are necessary when traditional methods are used to design the process of continuous casting immediately followed by rolling are expensive, new modelling concepts have been sought. Comprehensive tests were applied to solve problems related to the deformation of steel with a semi-solid core. Physical tests using specialist laboratory instruments (Gleeble 3800thermo-mechanical simulator, NANOTOM 180 N computer tomography, Zwick Z250 testing equipment, 3D blue-light scanning systems), and...

  12. Modeling of ionic transport in solid polymer electrolytes

    International Nuclear Information System (INIS)

    Cheang, P L; Teo, L L; Lim, T L

    2010-01-01

    A Monte Carlo model describing the ionic trans port in solid polyme relectrolyte is developed. Single cation simulation is carried out using hopping rate to study the transport mechanism of a thermally activated ion in solid polymer electrolyte. In our model, the ion is able to hop along a polymer chain and to jump between different chains, surmounting energy barriers that consist of polymer's activation energy and the externally applied electric field. The model is able to trace the motion of ion across polymer electrolyte. The mean hopping distance is calculated based on the available open bond in the next nearest side. Random numbers are used to determine the hopping distances, free flight times, final energy and direction of the cation after successful hop. Drift velocity and energy of cation are simulated in our work. The model is expected to be able to simulate the lithium-polymer battery in future.

  13. Consolidation modelling for thermoplastic composites forming simulation

    Science.gov (United States)

    Xiong, H.; Rusanov, A.; Hamila, N.; Boisse, P.

    2016-10-01

    Pre-impregnated thermoplastic composites are widely used in the aerospace industry for their excellent mechanical properties, Thermoforming thermoplastic prepregs is a fast manufacturing process, the automotive industry has shown increasing interest in this manufacturing processes, in which the reconsolidation is an essential stage. The model of intimate contact is investigated as the consolidation model, compression experiments have been launched to identify the material parameters, several numerical tests show the influents of the temperature and pressure applied during processing. Finally, a new solid-shell prismatic element has been presented for the simulation of consolidation step in the thermoplastic composites forming process.

  14. Phase-field model of vapor-liquid-solid nanowire growth

    Science.gov (United States)

    Wang, Nan; Upmanyu, Moneesh; Karma, Alain

    2018-03-01

    We present a multiphase-field model to describe quantitatively nanowire growth by the vapor-liquid-solid (VLS) process. The free-energy functional of this model depends on three nonconserved order parameters that distinguish the vapor, liquid, and solid phases and describe the energetic properties of various interfaces, including arbitrary forms of anisotropic γ plots for the solid-vapor and solid-liquid interfaces. The evolution equations for those order parameters describe basic kinetic processes including the rapid (quasi-instantaneous) equilibration of the liquid catalyst to a droplet shape with constant mean curvature, the slow incorporation of growth atoms at the droplet surface, and crystallization within the droplet. The standard constraint that the sum of the phase fields equals unity and the conservation of the number of catalyst atoms, which relates the catalyst volume to the concentration of growth atoms inside the droplet, are handled via separate Lagrange multipliers. An analysis of the model is presented that rigorously maps the phase-field equations to a desired set of sharp-interface equations for the evolution of the phase boundaries under the constraint of force balance at three-phase junctions (triple points) given by the Young-Herring relation that includes torque term related to the anisotropy of the solid-liquid and solid-vapor interface excess free energies. Numerical examples of growth in two dimensions are presented for the simplest case of vanishing crystalline anisotropy and the more realistic case of a solid-liquid γ plot with cusped minima corresponding to two sets of (10 ) and (11 ) facets. The simulations reproduce many of the salient features of nanowire growth observed experimentally, including growth normal to the substrate with tapering of the side walls, transitions between different growth orientations, and crawling growth along the substrate. They also reproduce different observed relationships between the nanowire growth

  15. An e-learning platform for aerospace medicine.

    Science.gov (United States)

    Bamidis, P D; Konstantinidis, S; Papadelis, C L; Perantoni, E; Styliadis, C; Kourtidou-Papadeli, C; Kourtidou-Papadeli, C; Pappas, C

    2008-08-01

    The appeal of online education and distance learning as an educational alternative is ever increasing. To support and accommodate the over-specialized knowledge available by different experts, information technology can be employed to develop virtual distributed pools of autonomous specialized educational modules and provide the mechanisms for retrieving and sharing them. New educational standards such as SCORM and Healthcare LOM enhance this process of sharing by offering qualities like interoperability, accessibility, and reusability, so that learning material remains credible, up-to-date and tracks changes and developments of medical techniques and standards through time. Given that only a few e-learning courses exist in aerospace medicine the material of which may be exchanged among teachers, the aim of this paper is to illustrate the procedure of creating a SCORM compliant course that incorporates notions of recent advances in social web technologies. The course is in accordance with main educational and technological details and is specific to pulmonary disorders in aerospace medicine. As new educational trends place much emphasis in continuing medical education, the expansion of a general practitioner's knowledge in topics such as aviation and aerospace pulmonary disorders for crew and passengers becomes a societal requirement.

  16. 2012 aerospace medical certification statistical handbook.

    Science.gov (United States)

    2013-12-01

    The annual Aerospace Medical Certification Statistical Handbook reports descriptive : characteristics of all active U.S. civil aviation airmen and the aviation medical examiners (AMEs) that : perform the required medical examinations. The 2012 annual...

  17. Trends in a aerospace technology advanced materials

    International Nuclear Information System (INIS)

    Ogren, J.R.

    1993-01-01

    The purpose of this presentation is to discuss recent trends in aerospace technology and to discuss as they relate to recent trends in the materials technologies. We shall do this within the framework of a large new activity that is, in fact, underway at the present, namely, MISSION TO THE PLANET EARTH. Mission requirements will be described in a hierarchical order. It will be shown that materials technology, in one form or another, is an identified critical technology for every single aspect of the mission. Other critical aspects exist, primarily in the areas of data processing and data management. International cooperation in aerospace-materials activities will be described. (author)

  18. Modelling elasticity in solids using active cubes - application to simulated operations

    DEFF Research Database (Denmark)

    Bro-Nielsen, Morten

    1995-01-01

    The paper describes an approach to elastic modelling of human tissue based on the use of 3D solid active models-active cubes (M. Bro-Nielsen, 1994)-and a shape description based on the metric tensor in a solid. Active cubes are used because they provide a natural parameterization of the surface a...

  19. Solid waste integrated cost analysis model: 1991 project year report

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The purpose of the City of Houston's 1991 Solid Waste Integrated Cost Analysis Model (SWICAM) project was to continue the development of a computerized cost analysis model. This model is to provide solid waste managers with tool to evaluate the dollar cost of real or hypothetical solid waste management choices. Those choices have become complicated by the implementation of Subtitle D of the Resources Conservation and Recovery Act (RCRA) and the EPA's Integrated Approach to managing municipal solid waste;. that is, minimize generation, maximize recycling, reduce volume (incinerate), and then bury (landfill) only the remainder. Implementation of an integrated solid waste management system involving all or some of the options of recycling, waste to energy, composting, and landfilling is extremely complicated. Factors such as hauling distances, markets, and prices for recyclable, costs and benefits of transfer stations, and material recovery facilities must all be considered. A jurisdiction must determine the cost impacts of implementing a number of various possibilities for managing, handling, processing, and disposing of waste. SWICAM employs a single Lotus 123 spreadsheet to enable a jurisdiction to predict or assess the costs of its waste management system. It allows the user to select his own process flow for waste material and to manipulate the model to include as few or as many options as he or she chooses. The model will calculate the estimated cost for those choices selected. The user can then change the model to include or exclude waste stream components, until the mix of choices suits the user. Graphs can be produced as a visual communication aid in presenting the results of the cost analysis. SWICAM also allows future cost projections to be made.

  20. Damage growth in aerospace composites

    CERN Document Server

    2015-01-01

    This book presents novel methods for the simulation of damage evolution in aerospace composites that will assist in predicting damage onset and growth and thus foster less conservative designs which realize the promised economic benefits of composite materials. The presented integrated numerical/experimental methodologies are capable of taking into account the presence of damage and its evolution in composite structures from the early phases of the design (conceptual design) through to the detailed finite element method analysis and verification phase. The book is based on the GARTEUR Research Project AG-32, which ran from 2007 to 2012, and documents the main results of that project. In addition, the state of the art in European projects on damage evolution in composites is reviewed. While the high specific strength and stiffness of composite materials make them suitable for aerospace structures, their sensitivity to damage means that designing with composites is a challenging task. The new approaches describ...

  1. Contribution to the modelling of gas-solid reactions and reactors; Contribution a la modelisation des reactions et des reacteurs gaz-solide

    Energy Technology Data Exchange (ETDEWEB)

    Patisson, F

    2005-09-15

    Gas-solid reactions control a great number of major industrial processes involving matter transformation. This dissertation aims at showing that mathematical modelling is a useful tool for both understanding phenomena and optimising processes. First, the physical processes associated with a gas-solid reaction are presented in detail for a single particle, together with the corresponding available kinetic grain models. A second part is devoted to the modelling of multiparticle reactors. Different approaches, notably for coupling grain models and reactor models, are illustrated through various case studies: coal pyrolysis in a rotary kiln, production of uranium tetrafluoride in a moving bed furnace, on-grate incineration of municipal solid wastes, thermogravimetric apparatus, nuclear fuel making, steel-making electric arc furnace. (author)

  2. 77 FR 58323 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Science.gov (United States)

    2012-09-20

    ... Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Airplanes AGENCY... Previously Held by Israel Aircraft Industries, Ltd.) Model Gulfstream G150 airplanes. This proposed AD was.... Discussion The Civil Aviation Authority of Israel (CAAI), which is the aviation authority for Israel, has...

  3. 77 FR 32069 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Science.gov (United States)

    2012-05-31

    ... Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Airplanes AGENCY... previously held by Israel Aircraft Industries, Ltd.) Model Galaxy and Gulfstream 200 airplanes. This proposed... receive about this proposed AD. Discussion The Civil Aviation Authority of Israel (CAAI), which is the...

  4. Plasma Processing of Model Residential Solid Waste

    Science.gov (United States)

    Messerle, V. E.; Mossé, A. L.; Nikonchuk, A. N.; Ustimenko, A. B.; Baimuldin, R. V.

    2017-09-01

    The authors have tested the technology of processing of model residential solid waste. They have developed and created a pilot plasma unit based on a plasma chamber incinerator. The waste processing technology has been tested and prepared for commercialization.

  5. 2011 aerospace medical certification statistical handbook.

    Science.gov (United States)

    2013-01-01

    The annual Aerospace Medical Certification Statistical Handbook reports descriptive characteristics of all active U.S. civil aviation airmen and the aviation medical examiners (AMEs) that perform the required medical examinations. The 2011 annual han...

  6. Cultivating a Grassroots Aerospace Innovation Culture at NASA Ames Research Center

    Science.gov (United States)

    D'Souza, Sarah; Sanchez, Hugo; Lewis, Ryan

    2017-01-01

    This paper details the adaptation of specific 'knowledge production' methods to implement a first of its kind, grassroots event that provokes a cultural change in how the NASA Ames civil servant community engages in the creation and selection of innovative ideas. Historically, selection of innovative proposals at NASA Ames Research Center is done at the highest levels of management, isolating the views and perspectives of the larger civil servant community. Additionally, NASA innovation programs are typically open to technical organizations and do not engage non-technical organizations to bring forward innovative processes/business practices. Finally, collaboration on innovative ideas and associated solutions tend to be isolated to organizational silos. In this environment, not all Ames employees feel empowered to innovate and opportunities for employee collaboration are limited. In order to address these issues, the 'innovation contest' method was adapted to create the NASA Ames Innovation Fair, a unique, grassroots innovation opportunity for the civil servant community. The Innovation Fair consisted of a physical event with a virtual component. The physical event provided innovators the opportunity to collaborate and pitch their innovations to the NASA Ames community. The civil servant community then voted for the projects that they viewed as innovative and would contribute to NASA's core mission, making this event a truly grassroots effort. The Innovation Fair website provided a location for additional knowledge sharing, discussion, and voting. On March 3rd, 2016, the 'First Annual NASA Ames Innovation Fair' was held with 49 innovators and more than 300 participants collaborating and/or voting for the best innovations. Based on the voting results, seven projects were awarded seed funding for projects ranging from innovative cost models to innovations in aerospace technology. Surveys of both innovators and Fair participants show the Innovation Fair was successful

  7. Nanomaterials and future aerospace technologies: opportunities and challenges

    Science.gov (United States)

    Vaia, Richard A.

    2012-06-01

    Two decades of extensive investment in nanomaterials, nanofabrication and nanometrology have provided the global engineering community a vast array of new technologies. These technologies not only promise radical change to traditional industries, such as transportation, information and aerospace, but may create whole new industries, such as personalized medicine and personalized energy harvesting and storage. The challenge today for the defense aerospace community is determining how to accelerate the conversion of these technical opportunities into concrete benefits with quantifiable impact, in conjunction with identifying the most important outstanding scientific questions that are limiting their utilization. For example, nanomaterial fabrication delivers substantial tailorablity beyond a traditional material data sheet. How can we integrate this tailorability into agile manufacturing and design methods to further optimize the performance, cost and durability of future resilient aerospace systems? The intersection of nano-based metamaterials and nanostructured devices with biotechnology epitomizes the technological promise of autonomous systems and enhanced human-machine interfaces. What then are the key materials and processes challenges that are inhibiting current lab-scale innovation from being integrated into functioning systems to increase effectiveness and productivity of our human resources? Where innovation is global, accelerating the use of breakthroughs, both for commercial and defense, is essential. Exploitation of these opportunities and finding solutions to the associated challenges for defense aerospace will rely on highly effective partnerships between commercial development, scientific innovation, systems engineering, design and manufacturing.

  8. Integrated Vehicle Health Management (IVHM) for Aerospace Systems

    Science.gov (United States)

    Baroth, Edmund C.; Pallix, Joan

    2006-01-01

    To achieve NASA's ambitious Integrated Space Transportation Program objectives, aerospace systems will implement a variety of new concept in health management. System level integration of IVHM technologies for real-time control and system maintenance will have significant impact on system safety and lifecycle costs. IVHM technologies will enhance the safety and success of complex missions despite component failures, degraded performance, operator errors, and environment uncertainty. IVHM also has the potential to reduce, or even eliminate many of the costly inspections and operations activities required by current and future aerospace systems. This presentation will describe the array of NASA programs participating in the development of IVHM technologies for NASA missions. Future vehicle systems will use models of the system, its environment, and other intelligent agents with which they may interact. IVHM will be incorporated into future mission planners, reasoning engines, and adaptive control systems that can recommend or execute commands enabling the system to respond intelligently in real time. In the past, software errors and/or faulty sensors have been identified as significant contributors to mission failures. This presentation will also address the development and utilization of highly dependable sohare and sensor technologies, which are key components to ensure the reliability of IVHM systems.

  9. The study and design of a national supply chain for the aerospace titanium components manufacturing industry

    Directory of Open Access Journals (Sweden)

    Lene van der Merwe

    2012-11-01

    Full Text Available Titanium’s strength-to-density ratio, corrosion resistance and high thermal compatibility makes it the perfect metal for aerospace. Titanium is for instance used for the structural airframe, seat tracks, engine components and landing gear of aircraft. The Boeing 787 that had its test flight in 2009 is one of the latest aircraft designs that incorporates a substantially higher percentage of parts manufactured from titanium due to the weight benefit. Titanium’s extensive use in aerospace applications ensures that the aerospace market is the main driver of titanium metal demand. South Africa is the second largest titanium producer in the world after Australia. The abundance of titanium in South Africa together with the growing demand has led it to be identified as a beneficiation priority in a collaborative government initiative, called Titanium Beneficiation Initiative (TBI. The purpose of this paper is to develop a supply chain model for the anticipated South African titanium component manufacturing industry.

  10. The Status and Future of Aerospace Engineering Education in Turkey.

    Science.gov (United States)

    Hale, Francis J.

    There is no aerospace industry in Turkey, and the level of operational activity is low even though the potential for the exploitation of aviation is high. The government of Turkey hopes to establish an aircraft factory in conjunction with a foreign contractor and is aware of the need for aerospace engineering education. This paper describes the…

  11. Job-mix modeling and system analysis of an aerospace multiprocessor.

    Science.gov (United States)

    Mallach, E. G.

    1972-01-01

    An aerospace guidance computer organization, consisting of multiple processors and memory units attached to a central time-multiplexed data bus, is described. A job mix for this type of computer is obtained by analysis of Apollo mission programs. Multiprocessor performance is then analyzed using: 1) queuing theory, under certain 'limiting case' assumptions; 2) Markov process methods; and 3) system simulation. Results of the analyses indicate: 1) Markov process analysis is a useful and efficient predictor of simulation results; 2) efficient job execution is not seriously impaired even when the system is so overloaded that new jobs are inordinately delayed in starting; 3) job scheduling is significant in determining system performance; and 4) a system having many slow processors may or may not perform better than a system of equal power having few fast processors, but will not perform significantly worse.

  12. Factors Influencing Advancement of Women Senior Leaders in Aerospace Companies

    Science.gov (United States)

    Garrett-Howard, Camille Elaine

    The problem researched in this study was the limited number of women in senior leadership positions in the aerospace industry. The purpose of this qualitative phenomenological research study was to interview women senior leaders in the aerospace industry to explore the factors they perceived as beneficial to their advancement to senior leadership positions in the aerospace industry. The research study was guided by a central research question relating to what professional and personal factors might have led to promotional opportunities into senior leadership roles. Transformational leadership was the conceptual framework used to inform the study. The qualitative, phenomenological approach was selected to gain insights of the lived experiences and perceptions relating to career advancement of women to senior leadership positions in the aerospace industry. Data were collected using a modified Van Kaam method, coded, and analyzed to discern themes or patterns. Findings were that the attributes participants contributed to their success, included a focus on leadership, personal development, and the importance of mentoring relationships. This study presented a positive direction in addressing the gaps in the body of knowledge related to women and leadership development by exploring the experiences of women in senior leadership positions in the aerospace industry. Implications for social change include informing organizations and women about specific leadership development practices as one way to promote more women into leadership positions thus reducing the gap between the number of men and women leaders.

  13. Determinants of premiums in aerospace mergers and acquisitions: A preliminary analysis

    Science.gov (United States)

    Bryant, John K.

    There is a large body of literature on different aspects of premiums as they relate to mergers and acquisitions. However, there is very little literature that specifically discusses the determinants of premiums in aerospace. Few industries have experienced the prolonged consolidation that the aerospace industry has seen. Today, the industry is dominated by a few large firms, but there is still merger activity continuing especially with second-tier firms attempting to secure their future through growth. This paper examines several determinants as applied to 18 aerospace mergers of publicly held companies and divisions from 1991 through April of 2002.

  14. A Model of Solid State Gas Sensors

    Science.gov (United States)

    Woestman, J. T.; Brailsford, A. D.; Shane, M.; Logothetis, E. M.

    1997-03-01

    Solid state gas sensors are widely used to measure the concentrations of gases such as CO, CH_4, C_3H_6, H_2, C_3H8 and O2 The applications of these sensors range from air-to-fuel ratio control in combustion processes including those in automotive engines and industrial furnaces to leakage detection of inflammable and toxic gases in domestic and industrial environments. As the need increases to accurately measure smaller and smaller concentrations, problems such as poor selectivity, stability and response time limit the use of these sensors. In an effort to overcome some of these limitations, a theoretical model of the transient behavior of solid state gas sensors has been developed. In this presentation, a model for the transient response of an electrochemical gas sensor to gas mixtures containing O2 and one reducing species, such as CO, is discussed. This model accounts for the transport of the reactive species to the sampling electrode, the catalyzed oxidation/reduction reaction of these species and the generation of the resulting electrical signal. The model will be shown to reproduce the results of published steady state models and to agree with experimental steady state and transient data.

  15. INFLUENCE OF AEROSPACE MEDICINE ACHIEVEMENTS ON THE DEVELOPMENT OF SPORT MEDICINE METHODOLOGY.

    Science.gov (United States)

    R Yashina, E R; Kurashvili, V A; Turzin, P S

    Modern technologies of aerospace medicine develop at rapid pace pulling on its orbit all spheres of the human activity, including sport. Innovations play a major role in the progress of sport medicine areas related to the biomedical support of precontest training. Overview of the most important aerospace medicine achievements and their methodical implications for sport medicine is presented. Discussion is devoted to how the aerospace medicine technologies can raise effectiveness of the biomedical support to different sectors of sport and fitness.

  16. Solid-Liquid equilibrium of n-alkanes using the Chain Delta Lattice Parameter model

    DEFF Research Database (Denmark)

    Coutinho, João A.P.; Andersen, Simon Ivar; Stenby, Erling Halfdan

    1996-01-01

    The formation of a solid phase in liquid mixtures with large paraffinic molecules is a phenomenon of interest in the petroleum, pharmaceutical, and biotechnological industries among onters. Efforts to model the solid-liquid equilibrium in these systems have been mainly empirical and with different...... degrees of success.An attempt to describe the equilibrium between the high temperature form of a paraffinic solid solution, commonly known as rotator phase, and the liquid phase is performed. The Chain Delta Lattice Parameter model (CDLP) is developed allowing a successful description of the solid-liquid...... equilibrium of n-alkanes ranging from n-C_20 to n-C_40.The model is further modified to achieve a more correct temperature dependence because it severely underestimates the excess enthalpy. It is shown that the ratio of excess enthalpy and entropy for n-alkane solid solutions, as happens for other solid...

  17. 76 FR 41432 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Science.gov (United States)

    2011-07-14

    ... Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Model Galaxy, Gulfstream... proposed AD. Discussion The Civil Aviation Authority (CAA), which is the aviation authority for Israel, has... Held by Israel Aircraft Industries, Ltd.): Docket No. FAA-2011-0716; Directorate Identifier 2011-NM-013...

  18. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 13: Source selection and information use by US aerospace engineers and scientists: Results of a telephone survey

    Science.gov (United States)

    Pinelli, Thomas E.; Glassman, Nanci A.

    1992-01-01

    A telephone survey of U.S. aerospace engineers and scientists belonging to the Society of Automotive Engineers (SAE) was conducted between December 4, 1991 and January 5, 1992. The survey was undertaken to (1) validate the telephone survey as an appropriate technique for collecting data from U.S. aerospace engineers and scientists; (2) collect information about how the results of NASA/DoD aerospace research are used in the R&D process; (3) identify those selection criteria which affect the use of federally-funded aerospace R&D; and (4) obtain information that could be used to develop a self-administered mail questionnaire for use with the same population. The average rating of importance of U.S. government technical reports was 2.5 (on a 4-point scale); The mean/median number of times U.S. government technical reports were used per 6 months was 8/2. Factors scoring highest for U.S. government technical reports were technical accuracy (2.9), reliable data and technical information (2.8), and contains comprehensive data and information (2.7) on a 4-point system. The factors scoring highest for influencing the use of U.S. government technical reports were relevance (3.1), technical accuracy (3.06), and reliable data/information (3.02). Ease of use, familiarity, technical accuracy, and relevance correlated with use of U.S. government technical reports. Survey demographics, survey questionnaire, and the NASA/DoD Aerospace Knowledge Diffusion Research Project publications list are included.

  19. Dominant supply chain co-ordination strategies in the Dutch aerospace industry

    NARCIS (Netherlands)

    Voordijk, Johannes T.; Meijboom, Bert

    2005-01-01

    Purpose – Firms in the aerospace industry face considerable pressure to improve co-ordination in their supply chains. The major question of the present study is what supply chain co-ordination strategies are dominant in the Dutch aerospace industry given the market environment of this industry?

  20. Applying the competence-based approach to management in the aerospace industry

    Directory of Open Access Journals (Sweden)

    Arpentieva Mariam

    2018-01-01

    Full Text Available Problems of management in aerospace manufacturing are similar to those we observe in other sectors, the main of which is the flattening of strategic management. The main reason lies in the attitude towards human resource of the organization. In the aerospace industry employs 250 thousand people, who need individual approach. The individual approach can offer competence-based approach to management. The purpose of the study is proof of the benefits of the competency approach to human resource management in context strategic management of the aerospace organization. To achieve this goal it is possible to obtain the method of comparative analysis. The article compares two approaches to personnel management. The transition to competence-based human resource management means (a a different understanding of the object of management; (b involvement in all functions of human resource management «knowledge – skills – abilities» of the employee; (c to change the approach to strategic management aerospace industry.

  1. Additive Manufacturing of Aerospace Propulsion Components

    Science.gov (United States)

    Misra, Ajay K.; Grady, Joseph E.; Carter, Robert

    2015-01-01

    The presentation will provide an overview of ongoing activities on additive manufacturing of aerospace propulsion components, which included rocket propulsion and gas turbine engines. Future opportunities on additive manufacturing of hybrid electric propulsion components will be discussed.

  2. National Aerospace Leadership Initiative - Phase 2

    Science.gov (United States)

    2010-03-01

    BNB Manufacturing, HMR Associates, PWA, UTRC, Sikorsky Helicopter, TCI MRO, Schwerdtle, Unilever , University of Hartford. In several cases parts were...HMR Associates, PWA, UTRC, Sikorsky Helicopter, TCI MRO, Schwerdtle, Unilever , University of Hartford National Aerospace Leadership Initiative

  3. Life-cycle assessment of municipal solid wastes: Development of the WASTED model

    International Nuclear Information System (INIS)

    Diaz, R.; Warith, M.

    2006-01-01

    This paper describes the development of the Waste Analysis Software Tool for Environmental Decisions (WASTED) model. This model provides a comprehensive view of the environmental impacts of municipal solid waste management systems. The model consists of a number of separate submodels that describe a typical waste management process: waste collection, material recovery, composting, energy recovery from waste and landfilling. These submodels are combined to represent a complete waste management system. WASTED uses compensatory systems to account for the avoided environmental impacts derived from energy recovery and material recycling. The model is designed to provide solid waste decision-makers and environmental researchers with a tool to evaluate waste management plans and to improve the environmental performance of solid waste management strategies. The model is user-friendly and compares favourably with other earlier models

  4. Investigating conceptual models for physical property couplings in solid solution models of cement

    International Nuclear Information System (INIS)

    Benbow, Steven; Watson, Claire; Savage, David

    2005-11-01

    The long-term behaviour of cementitious engineered barriers is an important process to consider when modelling the migration of radionuclides from a geological repository for nuclear waste. The modelling of cement is complicated by the fact that the cement is dominated by the behaviour of calcium silicate hydrate (CSH) gel which is a complex solid exhibiting incongruent dissolution behaviour. In this report, we have demonstrated the implementation of a solid-solution CSH gel model within a geochemical transport modelling framework using the Raiden computer code to investigate cement/concrete-groundwater interactions. The modelling conducted here shows that it is possible to couple various conceptual models for the evolution of physical properties of concrete with a solid solution model for cement degradation in a fully coupled geochemical transport model to describe the interaction of cement/concrete engineered barriers with groundwater. The results show that changes to the conceptual models and flow rates can give rise to very different evolutions. Most simulations were carried out at a reduced 'experimental' scale rather than full repository scale. The work has shown the possibility to investigate also the changing physical properties of degrading cement. To further develop the model more emphasis is needed on kinetics and the detailed development of a nearly clogged pore space. Modelling of the full repository scale could be another way forward to understand the behaviour of degrading concrete. A general conclusion is that the combined effects of chemical evolution and physical degradation should be analysed in performance assessments of cementitious repositories. Moreover, the project results will be used as one basis in coming reviews of SKB's safety assessments of repositories for spent fuel and low-and intermediate level waste

  5. CSIR in aerospace: An engine for future industrial growth

    CSIR Research Space (South Africa)

    Naidoo, Kavendra

    2017-10-01

    Full Text Available for industry impact 3 A brief summary of previous and current activities in SA aerospace Argos-II Airborne Observation System SumbandilaSat Satellite 4 RAVIN Light Aircraft JS1 Championship Glider Sling Light Sport Aircraft AIRBUS SUPPLIER... BOEING SUPPLIER SAAB Light Fighter Aircraft Airbus Military Transport Agusta Military Helicopter A brief summary of previous and current activities in SA aerospace A-Darter Short Range Air to Air Missile 5 Test flight centre Alkantpan...

  6. A review of multifunctional structure technology for aerospace applications

    Science.gov (United States)

    Sairajan, K. K.; Aglietti, G. S.; Mani, K. M.

    2016-03-01

    The emerging field of multifunctional structure (MFS) technologies enables the design of systems with reduced mass and volume, thereby improving their overall efficiency. It requires developments in different engineering disciplines and their integration into a single system without degrading their individual performances. MFS is particularly suitable for aerospace applications where mass and volume are critical to the cost of the mission. This article reviews the current state of the art of multifunctional structure technologies relevant to aerospace applications.

  7. Model of sustainable utilization of organic solids waste in Cundinamarca, Colombia

    Directory of Open Access Journals (Sweden)

    Solanyi Castañeda Torres

    2017-05-01

    Full Text Available Introduction: This article considers a proposal of a model of use of organic solids waste for the department of Cundinamarca, which responds to the need for a tool to support decision-making for the planning and management of organic solids waste. Objective: To perform an approximation of a conceptual technical and mathematician optimization model to support decision-making in order to minimize environmental impacts. Materials and methods: A descriptive study was applied due to the fact that some fundamental characteristics of the studied homogeneous phenomenon are presented and it is also considered to be quasi experimental. The calculation of the model for plants of the department is based on three axes (environmental, economic and social, that are present in the general equation of optimization. Results: A model of harnessing organic solids waste in the techniques of biological treatment of composting aerobic and worm cultivation is obtained, optimizing the system with the emissions savings of greenhouse gases spread into the atmosphere, and in the reduction of the overall cost of final disposal of organic solids waste in sanitary landfill. Based on the economic principle of utility that determines the environmental feasibility and sustainability in the plants of harnessing organic solids waste to the department, organic fertilizers such as compost and humus capture carbon and nitrogen that reduce the tons of CO2.

  8. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 66: Emerging Trends in the Globalization of Knowledge: The Role of the Technical Report in Aerospace Research and Development

    Science.gov (United States)

    Pinelli,Thomas E.; Golich, Vicki L.

    1997-01-01

    Economists, management theorists, business strategists, and governments alike recognize knowledge as the single most important resource in today's global economy. Because of its relationship to technological progress and economic growth, many governments have taken a keen interest in knowledge; specifically its production, transfer, and use. This paper focuses on the technical report as a product for disseminating the results of aerospace research and development (R&D) and its use and importance to aerospace engineers and scientists. The emergence of knowledge as an intellectual asset, its relationship to innovation, and its importance in a global economy provides the context for the paper. The relationships between government and knowledge and government and innovation are used to place knowledge within the context of publicly-funded R&D. Data, including the reader preferences of NASA technical reports, are derived from the NASA/DoD Aerospace Knowledge Diffusion Research Project, a ten-year study of knowledge diffusion in the U.S. aerospace industry.

  9. 76 FR 63571 - Airworthiness Directives; Eclipse Aerospace, Inc. Airplanes Equipped With Pratt & Whitney Canada...

    Science.gov (United States)

    2011-10-13

    ... engines manufactured for new production Eclipse Aerospace, Inc. Model EA500 airplanes will incorporate the... requires incorporating an operating limitation of a maximum operating altitude of 30,000 feet into Section 2, Limitations, of the airplane flight manual (AFM). Since we issued that AD, P&WC has developed a...

  10. Explicit Modeling of Solid Ocean Floor in Shallow Underwater Explosions

    Directory of Open Access Journals (Sweden)

    A.P. Walters

    2013-01-01

    Full Text Available Current practices for modeling the ocean floor in underwater explosion simulations call for application of an inviscid fluid with soil properties. A method for modeling the ocean floor as a Lagrangian solid, vice an Eulerian fluid, was developed in order to determine its effects on underwater explosions in shallow water using the DYSMAS solver. The Lagrangian solid bottom model utilized transmitting boundary segments, exterior nodal forces acting as constraints, and the application of prestress to minimize any distortions into the fluid domain. For simplicity, elastic materials were used in this current effort, though multiple constitutive soil models can be applied to improve the overall accuracy of the model. Even though this method is unable to account for soil cratering effects, it does however provide the distinct advantage of modeling contoured ocean floors such as dredged channels and sloped bottoms absent in Eulerian formulations. The study conducted here showed significant differences among the initial bottom reflections for the different solid bottom contours that were modeled. The most important bottom contour effect was the distortion to the gas bubble and its associated first pulse timing. In addition to its utility in bottom modeling, implementation of the non-reflecting boundary along with realistic material models can be used to drastically reduce the size of current fluid domains.

  11. Kinetic modelling of anaerobic hydrolysis of solid wastes, including disintegration processes

    Energy Technology Data Exchange (ETDEWEB)

    García-Gen, Santiago [Department of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, 15782 Santiago de Compostela (Spain); Sousbie, Philippe; Rangaraj, Ganesh [INRA, UR50, Laboratoire de Biotechnologie de l’Environnement, Avenue des Etangs, Narbonne F-11100 (France); Lema, Juan M. [Department of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, 15782 Santiago de Compostela (Spain); Rodríguez, Jorge, E-mail: jrodriguez@masdar.ac.ae [Department of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, 15782 Santiago de Compostela (Spain); Institute Centre for Water and Environment (iWater), Masdar Institute of Science and Technology, PO Box 54224 Abu Dhabi (United Arab Emirates); Steyer, Jean-Philippe; Torrijos, Michel [INRA, UR50, Laboratoire de Biotechnologie de l’Environnement, Avenue des Etangs, Narbonne F-11100 (France)

    2015-01-15

    Highlights: • Fractionation of solid wastes into readily and slowly biodegradable fractions. • Kinetic coefficients estimation from mono-digestion batch assays. • Validation of kinetic coefficients with a co-digestion continuous experiment. • Simulation of batch and continuous experiments with an ADM1-based model. - Abstract: A methodology to estimate disintegration and hydrolysis kinetic parameters of solid wastes and validate an ADM1-based anaerobic co-digestion model is presented. Kinetic parameters of the model were calibrated from batch reactor experiments treating individually fruit and vegetable wastes (among other residues) following a new protocol for batch tests. In addition, decoupled disintegration kinetics for readily and slowly biodegradable fractions of solid wastes was considered. Calibrated parameters from batch assays of individual substrates were used to validate the model for a semi-continuous co-digestion operation treating simultaneously 5 fruit and vegetable wastes. The semi-continuous experiment was carried out in a lab-scale CSTR reactor for 15 weeks at organic loading rate ranging between 2.0 and 4.7 g VS/L d. The model (built in Matlab/Simulink) fit to a large extent the experimental results in both batch and semi-continuous mode and served as a powerful tool to simulate the digestion or co-digestion of solid wastes.

  12. Regional integrated solid waste management: an optimization model for northern Lebanon

    International Nuclear Information System (INIS)

    Abou Najm, M.; El Fadel, M.; El-Taha, M.; Ayoub, G.; Al-Awar

    2000-01-01

    Full text.Increased environmental concerns and the emphasis on material and energy recovery are gradually changing the orientation of municipal solid waste (MSW) management and planning. In this context, the application of optimization techniques have been introduced to design the least cost solid waste management systems, considering the variety of management processes (recycling, composting, anaerobic digestion, incineration and land filling) and the existence of uncertainties associated with the number of system components and their interrelations. This study presents a model that was developed and applied to serve as a solid socio-economic and environmental considerations. The model accounts for solid waste generation rates, composition, collection, treatment, disposal as well as potential environmental impacts of various MSW management techniques. The model follows a linear programming formulation with the framework of dynamic optimization. The model can serve as a tool to evaluate various MSW management alternatives and obtain the optimal combination of technologies for the handling, treatment and disposal of MSW in an economic and environmentally sustainable way. The sensitivity of various waste management policies is also addressed. Finally, the region of Northern Lebanon was considered as a case study with data collected for the year 2000, to demonstrate the applicability of the model

  13. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 35: The use of computer networks in aerospace engineering

    Science.gov (United States)

    Bishop, Ann P.; Pinelli, Thomas E.

    1995-01-01

    This research used survey research to explore and describe the use of computer networks by aerospace engineers. The study population included 2000 randomly selected U.S. aerospace engineers and scientists who subscribed to Aerospace Engineering. A total of 950 usable questionnaires were received by the cutoff date of July 1994. Study results contribute to existing knowledge about both computer network use and the nature of engineering work and communication. We found that 74 percent of mail survey respondents personally used computer networks. Electronic mail, file transfer, and remote login were the most widely used applications. Networks were used less often than face-to-face interactions in performing work tasks, but about equally with reading and telephone conversations, and more often than mail or fax. Network use was associated with a range of technical, organizational, and personal factors: lack of compatibility across systems, cost, inadequate access and training, and unwillingness to embrace new technologies and modes of work appear to discourage network use. The greatest positive impacts from networking appear to be increases in the amount of accurate and timely information available, better exchange of ideas across organizational boundaries, and enhanced work flexibility, efficiency, and quality. Involvement with classified or proprietary data and type of organizational structure did not distinguish network users from nonusers. The findings can be used by people involved in the design and implementation of networks in engineering communities to inform the development of more effective networking systems, services, and policies.

  14. Aerospace engineering curriculum for the 21st century

    Science.gov (United States)

    Simitses, George J.

    1995-01-01

    The second year of the study was devoted to completing the information-gathering phase of this redesign effort, using the conclusions from that activity to prepare the initial structure for the new curriculum, publicizing activities to a wider engineering forum, and preparing the department faculty (Aerospace Engineering and Engineering Mechanics at University of Cincinnati) for the roles they will play in the curriculum redesign and implementation. These activities are summarized briefly in this progress report. Attached is a paper resulting from the data acquisition of this effort, 'Educating Aerospace Engineers for the Twenty-First Century: Results of a Survey.'

  15. 76 FR 435 - Airworthiness Directives; B/E Aerospace Protective Breathing Equipment (PBE) Part Number 119003...

    Science.gov (United States)

    2011-01-05

    ... Airworthiness Directives; B/E Aerospace Protective Breathing Equipment (PBE) Part Number 119003-11 Installed on... February 9, 2011. ADDRESSES: For service information identified in this AD, contact B/E Aerospace, Inc... Jersey Avenue, SE., Washington, DC 20590. FOR FURTHER INFORMATION CONTACT: David Fairback, Aerospace...

  16. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 37: The impact of political control on technical communications: A comparative study of Russian and US aerospace engineers and scientists

    Science.gov (United States)

    Barclay, Rebecca O.; Pinelli, Thomas E.; Flammia, Madelyn; Kennedy, John M.

    1994-01-01

    Until the recent dissolution of the Soviet Union, the Communist Party exerted a strict control of access to and dissemination of scientific and technical information (STI). This article presents models of the Soviet-style information society and the Western-style information society and discusses the effects of centralized governmental control of information on Russian technical communication practices. The effects of political control on technical communication are then used to interpret the results of a survey of Russian and U.S. aerospace engineers and scientists concerning the time devoted to technical communication, their collaborative writing practices and their attitudes toward collaboration, the kinds of technical documents they produce and use, and their use of computer technology, and their use of and the importance to them of libraries and technical information centers. The data are discussed in terms of tentative conclusions drawn from the literature. Finally, we conclude with four questions concerning government policy, collaboration, and the flow of STI between Russian and U.S. aerospace engineers and scientists.

  17. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 53: From student to entry-level professional: Examining the technical communications practices of early career-stage US aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Holloway, Karen; Barclay, Rebecca O.; Kennedy, John M.

    1995-01-01

    Studies indicate that communications and information-related activities take up a substantial portion of an engineer's work week; therefore, effective communications and information-use skills are one of the key engineering competencies that early career-stage aerospace engineers and scientists must possess to be successful. Feedback from industry rates communications and information-use skills high in terms of their importance to engineering practice; however, this same feedback rates the communications and information-use skills of early career-stage engineers low. To gather adequate and generalizable data about the communications and information-related activities of entry-level aerospace engineers and scientists, we surveyed 264 members of the AIAA who have no more than 1-5 years of aerospace engineering work experience. To learn more about the concomitant communications norms, we compared the results of this study with data (1,673 responses) we collected from student members of the AIAA and with data (341 responses) we collected from a study of aerospace engineering professionals. In this paper, we report selected results from these studies that focused on the communications practices and information-related activities of early career-stage U.S. aerospace engineers and scientists in the workplace.

  18. Ultrasonic Characterization of Aerospace Composites

    Science.gov (United States)

    Leckey, Cara; Johnston, Patrick; Haldren, Harold; Perey, Daniel

    2015-01-01

    Composite materials have seen an increased use in aerospace in recent years and it is expected that this trend will continue due to the benefits of reduced weight, increased strength, and other factors. Ongoing work at NASA involves the investigation of the large-scale use of composites for spacecraft structures (SLS components, Orion Composite Crew Module, etc). NASA is also involved in work to enable the use of composites in advanced aircraft structures through the Advanced Composites Project (ACP). In both areas (space and aeronautics) there is a need for new nondestructive evaluation and materials characterization techniques that are appropriate for characterizing composite materials. This paper will present an overview of NASA's needs for characterizing aerospace composites, including a description of planned and ongoing work under ACP for the detection of composite defects such as fiber waviness, reduced bond strength, delamination damage, and microcracking. The research approaches include investigation of angle array, guided wave, and phase sensitive ultrasonic methods. The use of ultrasonic simulation tools for optimizing and developing methods will also be discussed.

  19. Solid mechanics theory, modeling, and problems

    CERN Document Server

    Bertram, Albrecht

    2015-01-01

    This textbook offers an introduction to modeling the mechanical behavior of solids within continuum mechanics and thermodynamics. To illustrate the fundamental principles, the book starts with an overview of the most important models in one dimension. Tensor calculus, which is called for in three-dimensional modeling, is concisely presented in the second part of the book. Once the reader is equipped with these essential mathematical tools, the third part of the book develops the foundations of continuum mechanics right from the beginning. Lastly, the book’s fourth part focuses on modeling the mechanics of materials and in particular elasticity, viscoelasticity and plasticity. Intended as an introductory textbook for students and for professionals interested in self-study, it also features numerous worked-out examples to aid in understanding.

  20. NASA Aerospace Flight Battery Program: Generic Safety, Handling and Qualification Guidelines for Lithium-Ion (Li-Ion) Batteries; Availability of Source Materials for Lithium-Ion (Li-Ion) Batteries; Maintaining Technical Communications Related to Aerospace Batteries (NASA Aerospace Battery Workshop). Volume 2, Part 1

    Science.gov (United States)

    Manzo, Michelle A.; Brewer, Jeffrey C.; Bugga, Ratnakumar V.; Darcy, Eric C.; Jeevarajan, Judith A.; McKissock, Barbara I.; Schmitz, Paul C.

    2010-01-01

    This NASA Aerospace Flight Battery Systems Working Group was chartered within the NASA Engineering and Safety Center (NESC). The Battery Working Group was tasked to complete tasks and to propose proactive work to address battery related, agency-wide issues on an annual basis. In its first year of operation, this proactive program addressed various aspects of the validation and verification of aerospace battery systems for NASA missions. Studies were performed, issues were discussed and in many cases, test programs were executed to generate recommendations and guidelines to reduce risk associated with various aspects of implementing battery technology in the aerospace industry. This report contains the Appendices to the findings from the first year of the program's operations.

  1. Investigating conceptual models for physical property couplings in solid solution models of cement

    Energy Technology Data Exchange (ETDEWEB)

    Benbow, Steven; Watson, Claire; Savage, David [Quintesssa Ltd., Henley-on-Thames (United Kingdom)

    2005-11-15

    The long-term behaviour of cementitious engineered barriers is an important process to consider when modelling the migration of radionuclides from a geological repository for nuclear waste. The modelling of cement is complicated by the fact that the cement is dominated by the behaviour of calcium silicate hydrate (CSH) gel which is a complex solid exhibiting incongruent dissolution behaviour. In this report, we have demonstrated the implementation of a solid-solution CSH gel model within a geochemical transport modelling framework using the Raiden computer code to investigate cement/concrete-groundwater interactions. The modelling conducted here shows that it is possible to couple various conceptual models for the evolution of physical properties of concrete with a solid solution model for cement degradation in a fully coupled geochemical transport model to describe the interaction of cement/concrete engineered barriers with groundwater. The results show that changes to the conceptual models and flow rates can give rise to very different evolutions. Most simulations were carried out at a reduced 'experimental' scale rather than full repository scale. The work has shown the possibility to investigate also the changing physical properties of degrading cement. To further develop the model more emphasis is needed on kinetics and the detailed development of a nearly clogged pore space. Modelling of the full repository scale could be another way forward to understand the behaviour of degrading concrete. A general conclusion is that the combined effects of chemical evolution and physical degradation should be analysed in performance assessments of cementitious repositories. Moreover, the project results will be used as one basis in coming reviews of SKB's safety assessments of repositories for spent fuel and low-and intermediate level waste.

  2. IT Data Mining Tool Uses in Aerospace

    Science.gov (United States)

    Monroe, Gilena A.; Freeman, Kenneth; Jones, Kevin L.

    2012-01-01

    Data mining has a broad spectrum of uses throughout the realms of aerospace and information technology. Each of these areas has useful methods for processing, distributing, and storing its corresponding data. This paper focuses on ways to leverage the data mining tools and resources used in NASA's information technology area to meet the similar data mining needs of aviation and aerospace domains. This paper details the searching, alerting, reporting, and application functionalities of the Splunk system, used by NASA's Security Operations Center (SOC), and their potential shared solutions to address aircraft and spacecraft flight and ground systems data mining requirements. This paper also touches on capacity and security requirements when addressing sizeable amounts of data across a large data infrastructure.

  3. Thermal Expansion Properties of Aerospace Materials

    Science.gov (United States)

    Green, E. F.

    1969-01-01

    Thermal expansion properties of materials used in aerospace systems are compiled into a single handbook. The data, derived from experimental measurements supplemented by information from literature sources, are presented in charts and tables arranged in two sections, covering cryogenic and elevated temperatures.

  4. Ceramic composites: Enabling aerospace materials

    Science.gov (United States)

    Levine, S. R.

    1992-01-01

    Ceramics and ceramic matrix composites (CMC) have the potential for significant impact on the performance of aerospace propulsion and power systems. In this paper, the potential benefits are discussed in broad qualitative terms and are illustrated by some specific application case studies. The key issues in need of resolution for the potential of ceramics to be realized are discussed.

  5. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 22: US academic librarians and technical information specialists as information intermediaries: Results of the phase 3 survey

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis U.S. academic librarians and technical information specialists as information intermediaries.

  6. Solid Waste Projection Model: Database User's Guide

    International Nuclear Information System (INIS)

    Blackburn, C.L.

    1993-10-01

    The Solid Waste Projection Model (SWPM) system is an analytical tool developed by Pacific Northwest Laboratory (PNL) for Westinghouse Hanford Company (WHC) specifically to address Hanford solid waste management issues. This document is one of a set of documents supporting the SWPM system and providing instructions in the use and maintenance of SWPM components. This manual contains instructions for using Version 1.4 of the SWPM database: system requirements and preparation, entering and maintaining data, and performing routine database functions. This document supports only those operations which are specific to SWPM database menus and functions and does not Provide instruction in the use of Paradox, the database management system in which the SWPM database is established

  7. Chemical Gas Sensors for Aerospace Applications

    Science.gov (United States)

    Hunter, Gary W.; Liu, C. C.

    1998-01-01

    Chemical sensors often need to be specifically designed (or tailored) to operate in a given environment. It is often the case that a chemical sensor that meets the needs of one application will not function adequately in another application. The more demanding the environment and specialized the requirement, the greater the need to adapt exiting sensor technologies to meet these requirements or, as necessary, develop new sensor technologies. Aerospace (aeronautic and space) applications are particularly challenging since often these applications have specifications which have not previously been the emphasis of commercial suppliers. Further, the chemical sensing needs of aerospace applications have changed over the years to reflect the changing emphasis of society. Three chemical sensing applications of particular interest to the National Aeronautics and Space Administration (NASA) which illustrate these trends are launch vehicle leak detection, emission monitoring, and fire detection. Each of these applications reflects efforts ongoing throughout NASA. As described in NASA's "Three Pillars for Success", a document which outlines NASA's long term response to achieve the nation's priorities in aerospace transportation, agency wide objectives include: improving safety and decreasing the cost of space travel, significantly decreasing the amount of emissions produced by aeronautic engines, and improving the safety of commercial airline travel. As will be discussed below, chemical sensing in leak detection, emission monitoring, and fire detection will help enable the agency to meet these objectives. Each application has vastly different problems associated with the measurement of chemical species. Nonetheless, the development of a common base technology can address the measurement needs of a number of applications.

  8. Community Learning Process: A Model of Solid Waste Reduction and Separation

    Directory of Open Access Journals (Sweden)

    Jittree Pothimamaka

    2008-07-01

    Full Text Available The main purpose of this research was to study and develop an appropriate model of waste reduction and separation in the community under the community learning process. This is a research and development (R&D study with mixed methodology consisting of four steps. Step One: Research was conducted to obtain information on solid waste disposal in Bang Sue District, Bangkok Metropolis, Thailand, employing group discussions with community members and data collection from the field. Step Two: The activities for development of the model consisted of group discussions, workshops, and development of a test of knowledge and behaviors concerning solid waste disposal using the 1A3R practice concept. Step Three : Experimentation with the model consisting of pre testing and post testing of knowledge and behaviors concerning solid waste disposal ; door to door imparting of appropriate knowledge and behaviors concerning solid waste disposal ; and collecting of data on the rate and amount of generated waste, and waste separation. Step Four: Evaluation of the developed model consisting of assessments based on physical indicators of the waste, opinions of experts, and impacts on participating communities. The findings revealed that (1 the post experiment knowledge and behavior mean scores of community members in the sample significantly increased over their pre experiment counterparts; and (2 the rate of waste generation decreased while waste separation increased. The proposed model of solid waste reduction and separation was accepted, and has four main components:(1 Community Practice: solid waste should be separated in the household into three types: food waste, marketable waste and non marketable waste must be clearly separated from household waste.(2 Knowledge sharing: door to door imparting of knowledge and behaviors on solid waste reduction and separation based on the 1A3R practice concept should be promoted.(3 Community mastery: the community organization

  9. [NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 4:] Technical communications in aerospace: An analysis of the practices reported by US and European aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.; Glassman, Myron

    1990-01-01

    Results are reported from pilot surveys on the use of scientific and technical information (STI) by U.S. and NATO-nation aerospace scientists and engineers, undertaken as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. The survey procedures and the demographic characteristics of the 67 scientists and engineers who responded to the survey are summarized, and the results are presented in a series of tables and discussed in detail. Findings emphasized include: (1) both U.S. and NATO respondents spend around 60 percent of their work week producing or using STI products; (2) NATO respondents are more likely than their U.S. counterparts to use 'formal' STI products (like technical reports and papers) and the services of librarians and online data bases; (3) most of the respondents use computers and information technology in preparing STI products; and (4) respondents who had taken courses in technical communication agreed on the value and ideal subject matter of such courses.

  10. Modal parameter determination of a lightweight aerospace panel using laser Doppler vibrometer measurements

    Science.gov (United States)

    de Sousa, Kleverson C.; Domingues, Allan C.; Pereira, Pedro P. de S.; Carneiro, Sergio H.; de Morais, Marcus V. G.; Fabro, Adriano T.

    2016-06-01

    The experimental determination of modal parameters, i.e. natural frequencies, mode shapes and damping ratio, are key in characterizing the dynamic behaviour of structures. Typically, such parameters are obtained from dynamic measurements using one or a set of accelerometers, for response measurements, along with force transducers from an impact hammer or an electrodynamic actuator, i.e. a shaker. However, lightweight structures, commonly applied in the aerospace industry, can be significantly affected by the added mass from accelerometers. Therefore, non-contact measurement techniques, like Laser Doppler Vibrometer (LDV), are a more suitable approach in determining the dynamic characteristics of such structures. In this article, the procedures and results of a modal test for a honeycomb sandwich panel for aerospace applications are presented and discussed. The main objectives of the test are the identification of natural frequencies and mode shapes in order to validate a numerical model, as well as the identification of the damping characteristics of the panel. A validated numerical model will be necessary for future detailed response analysis of the satellite, including vibroacoustic investigations to account for acoustic excitations encountered during launching. The numerical model using homogenised material properties is updated to fit the experimental results and very good agreement between experimental and numerically obtained natural frequencies and mode shapes.

  11. Rakesh K. Kapania named Norris and Laura Mitchell Professor of Aerospace Engineering

    OpenAIRE

    Crumbley, Liz

    2008-01-01

    Rakesh K. Kapania, a professor in the Department of Aerospace and Ocean Engineering in the College of Engineering at Virginia Tech, was appointed the Norris and Laura Mitchell Professor of Aerospace Engineering by the Virginia Tech Board of Visitors during the board's quarterly meeting March 31.

  12. Frequency Response Function Based Damage Identification for Aerospace Structures

    Science.gov (United States)

    Oliver, Joseph Acton

    Structural health monitoring technologies continue to be pursued for aerospace structures in the interests of increased safety and, when combined with health prognosis, efficiency in life-cycle management. The current dissertation develops and validates damage identification technology as a critical component for structural health monitoring of aerospace structures and, in particular, composite unmanned aerial vehicles. The primary innovation is a statistical least-squares damage identification algorithm based in concepts of parameter estimation and model update. The algorithm uses frequency response function based residual force vectors derived from distributed vibration measurements to update a structural finite element model through statistically weighted least-squares minimization producing location and quantification of the damage, estimation uncertainty, and an updated model. Advantages compared to other approaches include robust applicability to systems which are heavily damped, large, and noisy, with a relatively low number of distributed measurement points compared to the number of analytical degrees-of-freedom of an associated analytical structural model (e.g., modal finite element model). Motivation, research objectives, and a dissertation summary are discussed in Chapter 1 followed by a literature review in Chapter 2. Chapter 3 gives background theory and the damage identification algorithm derivation followed by a study of fundamental algorithm behavior on a two degree-of-freedom mass-spring system with generalized damping. Chapter 4 investigates the impact of noise then successfully proves the algorithm against competing methods using an analytical eight degree-of-freedom mass-spring system with non-proportional structural damping. Chapter 5 extends use of the algorithm to finite element models, including solutions for numerical issues, approaches for modeling damping approximately in reduced coordinates, and analytical validation using a composite

  13. Proceedings of the 4th Conference on Aerospace Materials, Processes, and Environmental Technology

    Science.gov (United States)

    Griffin, D. E. (Editor); Stanley, D. C. (Editor)

    2001-01-01

    The next millennium challenges us to produce innovative materials, processes, manufacturing, and environmental technologies that meet low-cost aerospace transportation needs while maintaining US leadership. The pursuit of advanced aerospace materials, manufacturing processes, and environmental technologies supports the development of safer, operational, next-generation, reusable, and expendable aeronautical and space vehicle systems. The Aerospace Materials, Processes, and Environmental Technology Conference (AMPET) provided a forum for manufacturing, environmental, materials, and processes engineers, scientists, and managers to describe, review, and critically assess advances in these key technology areas.

  14. Interface model conditions for a non-equilibrium heat transfer model for conjugate fluid/porous/solid domains

    International Nuclear Information System (INIS)

    Betchen, L.J.; Straatman, A.G.

    2005-01-01

    A mathematical and numerical model for the treatment of conjugate fluid flow and heat transfer problems in domains containing pure fluid, porous, and pure solid regions has been developed. The model is general and physically reasoned, and allows for local thermal non-equilibrium in the porous region. The model is developed for implementation on a simple collocated finite volume grid. Of particular novelty are the conditions implemented at the interfaces between porous regions, and those containing a pure solid or pure fluid. The model is validated by simulation of a three-dimensional porous plug problem for which experimental results are available. (author)

  15. O modelo de integração de sistemas da indústria aeronáutica: fatores motivadores Systems integration model in the aerospace industry: motivating factors

    Directory of Open Access Journals (Sweden)

    João Henrique Lopes Guerra

    2011-01-01

    Full Text Available A ampliação das alianças estratégicas na indústria aeronáutica mostra uma clara opção dos fabricantes de avião por um modelo de integração de sistemas em que eles concentram o seu foco em atividades relacionadas às suas competências essenciais. Apesar da importância desta indústria e embora os principais fabricantes de avião do mundo estejam adotando este modelo, a literatura sobre este tema ainda é escassa e, mesmo a existente, encontra-se muito fragmentada. Este trabalho, qualitativo e de cunho teórico-conceitual, aproveita a literatura disponível e observa a movimentação dos principais fabricantes de avião do mundo para identificar e compreender os fatores que os têm motivado a adotar este modelo. Os seguintes fatores foram identificados: o interesse em tecnologias e empresas especializadas, os acordos de offset e as grandes barreiras e riscos existentes na indústria aeronáutica. Como decorrência do modelo de integração de sistemas, a indústria aeronáutica sofre atualmente uma agressiva desintegração vertical.The increase in the number of strategic alliances in the aerospace industry shows a clear option of the aircraft manufacturers for a system integration model in which they can concentrate their focus on activities related to their core competences. Despite the importance of this industry and the fact that the major aircraft manufacturers in the world have adopted this model, the literature on this subject is rather scarce and fragmented. A qualitative and theoretical-conceptual research was carried out making use of the available literature and investigating the movement of the major aircraft manufacturers in the world to identify and understand the factors that have been motivating them to adopt this model. The following factors were identified: the interest in specialized technologies and companies, the offset agreements, and the great barriers and risks in the aerospace industry. Due to the system

  16. Spreadsheet Modeling of Electron Distributions in Solids

    Science.gov (United States)

    Glassy, Wingfield V.

    2006-01-01

    A series of spreadsheet modeling exercises constructed as part of a new upper-level elective course on solid state materials and surface chemistry is described. The spreadsheet exercises are developed to provide students with the opportunity to interact with the conceptual framework where the role of the density of states and the Fermi-Dirac…

  17. Aerospace Structures Test Facility Environmental Test Chambers (ETC)

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The ETCs test the structural integrity of aerospace structures in representative operating temperatures and aerodynamic load distributions. The test article...

  18. Microstructural model for the plasticity of amorphous solids

    NARCIS (Netherlands)

    Hütter, M.; Breemen, van L.C.A.

    2012-01-01

    Based on the concept of localized shear transformation zones (STZ), a thermodynamically consistent model for the viscoplastic deformation of amorphous solids is developed. The approach consists of a dynamic description of macroscopic viscoplasticity that is enriched by the evolution of number

  19. Fabrication of metal matrix composite by semi-solid powder processing

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yufeng [Iowa State Univ., Ames, IA (United States)

    2011-01-01

    Various metal matrix composites (MMCs) are widely used in the automotive, aerospace and electrical industries due to their capability and flexibility in improving the mechanical, thermal and electrical properties of a component. However, current manufacturing technologies may suffer from insufficient process stability and reliability and inadequate economic efficiency and may not be able to satisfy the increasing demands placed on MMCs. Semi-solid powder processing (SPP), a technology that combines traditional powder metallurgy and semi-solid forming methods, has potential to produce MMCs with low cost and high efficiency. In this work, the analytical study and experimental investigation of SPP on the fabrication of MMCs were explored. An analytical model was developed to understand the deformation mechanism of the powder compact in the semi-solid state. The densification behavior of the Al6061 and SiC powder mixtures was investigated with different liquid fractions and SiC volume fractions. The limits of SPP were analyzed in terms of reinforcement phase loading and its impact on the composite microstructure. To explore adoption of new materials, carbon nanotube (CNT) was investigated as a reinforcing material in aluminum matrix using SPP. The process was successfully modeled for the mono-phase powder (Al6061) compaction and the density and density distribution were predicted. The deformation mechanism at low and high liquid fractions was discussed. In addition, the compaction behavior of the ceramic-metal powder mixture was understood, and the SiC loading limit was identified by parametric study. For the fabrication of CNT reinforced Al6061 composite, the mechanical alloying of Al6061-CNT powders was first investigated. A mathematical model was developed to predict the CNT length change during the mechanical alloying process. The effects of mechanical alloying time and processing temperature during SPP were studied on the mechanical, microstructural and

  20. Application of aerospace failure-reporting systems to power plants. Final report

    International Nuclear Information System (INIS)

    Koukol, J.F.; Lapin, E.E.; Leverton, W.F.; Pickering, W.H.

    1980-06-01

    Failure reporting and analysis is a principal element of the overall quality assurance scheme that helped achieve, and now sustains, a high level of reliability in our national aerospace effort. The aerospace endeavor has many points of congruence with other highly technological activities. These are marked by great economic investment, an extended interval between concept and final implementation, the involvement of many independent entities with the government exercising a dominating influence, a considerable exposure to public view and review by public bodies, a notoriety accompanying untoward events, and extreme consequences attending failure. This report is written in the expectation that the lessons learned in arriving at the present state in aerospace can be adopted by others. It is the object of the report to illuminate the essential features of the aerospace failure reporting system. Two schemes are described. One typifies that which is currently employed by the Jet Propulsion Laboratory (JPL) operated by the California Institute of Technology for the NASA/JPL Voyager project and is based on procedures developed over several decades of deep space exploration. The other is typical of that employed by the Space Divison of the Air Force for military space programs

  1. NASA-UVA Light Aerospace Alloy and Structures Technology Program (LA2ST). Research on Materials for the High Speed Civil Transport

    Science.gov (United States)

    Gangloff, Richard P.; Starke, Edgar A., Jr.; Kelly, Robert G.; Scully, John R.; Stoner, Glenn E.; Wert, John A.

    1997-01-01

    Since 1986, the NASA-Langley Research Center has sponsored the NASA-UVa Light Alloy and Structures Technology (LA2ST) Program at the University of Virginia (UVa). The fundamental objective of the LA2ST program is to conduct interdisciplinary graduate student research on the performance of next generation, light-weight aerospace alloys, composites and thermal gradient structures. The LA2ST program has aimed to product relevant data and basic understanding of material mechanical response, environmental/corrosion behavior, and microstructure; new monolithic and composite alloys; advanced processing methods; measurement and modeling advances; and a pool of educated graduate students for aerospace technologies. The scope of the LA2ST Program is broad. Research areas include: (1) Mechanical and Environmental Degradation Mechanisms in Advanced Light Metals and Composites, (2) Aerospace Materials Science, (3) Mechanics of materials for Aerospace Structures, and (4) Thermal Gradient Structures. A substantial series of semi-annual progress reports issued since 1987 documents the technical objectives, experimental or analytical procedures, and detailed results of graduate student research in these topical areas.

  2. Three-phase boundary length in solid-oxide fuel cells: A mathematical model

    Energy Technology Data Exchange (ETDEWEB)

    Janardhanan, Vinod M. [Institutefor Chemical Technology and Polymer Chemistry, University of Karlsruhe (TH), Kaiserstr. 12, D-76128 Karlsruhe (Germany); Heuveline, Vincent; Deutschmann, Olaf [Institute for Applied and Numerical Mathematics, University of Karlsruhe (TH), Kaiserstr. 12, D-76128 Karlsruhe (Germany)

    2008-03-15

    A mathematical model to calculate the volume specific three-phase boundary length in the porous composite electrodes of solid-oxide fuel cell is presented. The model is exclusively based on geometrical considerations accounting for porosity, particle diameter, particle size distribution, and solids phase distribution. Results are presented for uniform particle size distribution as well as for non-uniform particle size distribution. (author)

  3. Three-phase boundary length in solid-oxide fuel cells: A mathematical model

    Science.gov (United States)

    Janardhanan, Vinod M.; Heuveline, Vincent; Deutschmann, Olaf

    A mathematical model to calculate the volume specific three-phase boundary length in the porous composite electrodes of solid-oxide fuel cell is presented. The model is exclusively based on geometrical considerations accounting for porosity, particle diameter, particle size distribution, and solids phase distribution. Results are presented for uniform particle size distribution as well as for non-uniform particle size distribution.

  4. Model-supported interpretation of the electrochemical characteristics of solid oxide fuel cells with Ni/YSZ cermet anodes; Modellgestuetzte Interpretation der elektrochemischen Charakteristik von Festoxid-Brennstoffzellen mit Ni/YSZ-Cermetanoden

    Energy Technology Data Exchange (ETDEWEB)

    Gewies, Stefan

    2009-01-29

    This work presents the development, validation and application of a multiscale model for the detailed description of a solid oxide fuel cell (SOFC) with a Ni/YSZ (nickel/yttria-stabilized zirconia) cermet anode. The aim of the study is the identification of the physico-chemical loss processes, as seen in impedance spectra and polarization curves. The model consists of an elementary kinetic description of the electrochemistry including the development of an electrical double layer at the electrode/electrolyte interface of the cermet anode, a homogenized description of charge and gas-phase transport in the electrodes as well as a macroscopic description of convective and diffusive mass transport in the gas phase above the electrodes. For the rst time this study allows for a complete description of the impedance spectra of a diffusively fuel-supplied cermet anode. By comparing simulations with experiments on symmetrical cells (University of Karlsruhe) three dominant loss processes could be identified. The model was extended to account for the description of segmented SOFCs. In correspondence with experimental data (German Aerospace Center) the simulations show strong gradients in current densities and gas concentrations. (orig.)

  5. Modeling the Behaviour of an Advanced Material Based Smart Landing Gear System for Aerospace Vehicles

    International Nuclear Information System (INIS)

    Varughese, Byji; Dayananda, G. N.; Rao, M. Subba

    2008-01-01

    The last two decades have seen a substantial rise in the use of advanced materials such as polymer composites for aerospace structural applications. In more recent years there has been a concerted effort to integrate materials, which mimic biological functions (referred to as smart materials) with polymeric composites. Prominent among smart materials are shape memory alloys, which possess both actuating and sensory functions that can be realized simultaneously. The proper characterization and modeling of advanced and smart materials holds the key to the design and development of efficient smart devices/systems. This paper focuses on the material characterization; modeling and validation of the model in relation to the development of a Shape Memory Alloy (SMA) based smart landing gear (with high energy dissipation features) for a semi rigid radio controlled airship (RC-blimp). The Super Elastic (SE) SMA element is configured in such a way that it is forced into a tensile mode of high elastic deformation. The smart landing gear comprises of a landing beam, an arch and a super elastic Nickel-Titanium (Ni-Ti) SMA element. The landing gear is primarily made of polymer carbon composites, which possess high specific stiffness and high specific strength compared to conventional materials, and are therefore ideally suited for the design and development of an efficient skid landing gear system with good energy dissipation characteristics. The development of the smart landing gear in relation to a conventional metal landing gear design is also dealt with

  6. Developing and modelling of ohmic heating for solid food products

    DEFF Research Database (Denmark)

    Feyissa, Aberham Hailu; Frosch, Stina

    Heating of solid foods using the conventional technologies is time-consuming due to the fact that heat transfer is limited by internal conduction within the product. This is a big challenge to food manufactures who wish to heat the product faster to the desired core temperature and to ensure more...... uniform quality across the product. Ohmic heating is one of the novel technologies potentially solving this problem by allowing volumetric heating of the product and thereby reducing or eliminating temperature gradients within the product. However, the application of ohmic heating for solid food products...... such as meat and seafood is not industrially utilized yet. Therefore, the aim of the current work is to model and develop the ohmic heating technology for heating of solid meat and seafood. A 3D mathematical model of coupled heat transfer and electric field during ohmic heating of meat products has been...

  7. Occupational Survey Report. AFSC 4M0X1 Aerospace Physiology

    Science.gov (United States)

    2002-05-01

    Chamber NCOIC Job Hyperbaric Chamber Specialist Job • Perform Type 2, 4 and 1 chamber flights • Perform inside observer duties during hypobaric ...78% Hyperbaric Chamber Specialist Independent Job 4% Not Grouped 2% U2 Aerospace Physiology Cluster 10% Job Structure Sample size: 168 Aerospace...Altitude Chamber Cluster (N=130) Hypobaric Chamber Instructor/Monitor Job HAAMS Job Altitude Chamber Apprentice Job 78% UPT Parasail Job Altitude

  8. Sewer solids separation by sedimentation--the problem of modeling, validation and transferability.

    Science.gov (United States)

    Kutzner, R; Brombach, H; Geiger, W F

    2007-01-01

    Sedimentation of sewer solids in tanks, ponds and similar devices is the most relevant process for the treatment of stormwater and combined sewer overflows in urban collecting systems. In the past a lot of research work was done to develop deterministic models for the description of this separation process. But these modern models are not commonly accepted in Germany until today. Water Authorities are sceptical with regard to model validation and transferability. Within this paper it is checked whether this scepticism is reasonable. A framework-proposal for the validation of mathematical models with zero or one dimensional spatial resolution for particle separation processes for stormwater and combined sewer overflow treatment is presented. This proposal was applied to publications of repute on sewer solids separation by sedimentation. The result was that none of the investigated models described in literature passed the validation entirely. There is an urgent need for future research in sewer solids sedimentation and remobilization!

  9. Revisiting low-fidelity two-fluid models for gas–solids transport

    Energy Technology Data Exchange (ETDEWEB)

    Adeleke, Najeem, E-mail: najm@psu.edu; Adewumi, Michael, E-mail: m2a@psu.edu; Ityokumbul, Thaddeus

    2016-08-15

    Two-phase gas–solids transport models are widely utilized for process design and automation in a broad range of industrial applications. Some of these applications include proppant transport in gaseous fracking fluids, air/gas drilling hydraulics, coal-gasification reactors and food processing units. Systems automation and real time process optimization stand to benefit a great deal from availability of efficient and accurate theoretical models for operations data processing. However, modeling two-phase pneumatic transport systems accurately requires a comprehensive understanding of gas–solids flow behavior. In this study we discuss the prevailing flow conditions and present a low-fidelity two-fluid model equation for particulate transport. The model equations are formulated in a manner that ensures the physical flux term remains conservative despite the inclusion of solids normal stress through the empirical formula for modulus of elasticity. A new set of Roe–Pike averages are presented for the resulting strictly hyperbolic flux term in the system of equations, which was used to develop a Roe-type approximate Riemann solver. The resulting scheme is stable regardless of the choice of flux-limiter. The model is evaluated by the prediction of experimental results from both pneumatic riser and air-drilling hydraulics systems. We demonstrate the effect and impact of numerical formulation and choice of numerical scheme on model predictions. We illustrate the capability of a low-fidelity one-dimensional two-fluid model in predicting relevant flow parameters in two-phase particulate systems accurately even under flow regimes involving counter-current flow.

  10. Revisiting low-fidelity two-fluid models for gas–solids transport

    International Nuclear Information System (INIS)

    Adeleke, Najeem; Adewumi, Michael; Ityokumbul, Thaddeus

    2016-01-01

    Two-phase gas–solids transport models are widely utilized for process design and automation in a broad range of industrial applications. Some of these applications include proppant transport in gaseous fracking fluids, air/gas drilling hydraulics, coal-gasification reactors and food processing units. Systems automation and real time process optimization stand to benefit a great deal from availability of efficient and accurate theoretical models for operations data processing. However, modeling two-phase pneumatic transport systems accurately requires a comprehensive understanding of gas–solids flow behavior. In this study we discuss the prevailing flow conditions and present a low-fidelity two-fluid model equation for particulate transport. The model equations are formulated in a manner that ensures the physical flux term remains conservative despite the inclusion of solids normal stress through the empirical formula for modulus of elasticity. A new set of Roe–Pike averages are presented for the resulting strictly hyperbolic flux term in the system of equations, which was used to develop a Roe-type approximate Riemann solver. The resulting scheme is stable regardless of the choice of flux-limiter. The model is evaluated by the prediction of experimental results from both pneumatic riser and air-drilling hydraulics systems. We demonstrate the effect and impact of numerical formulation and choice of numerical scheme on model predictions. We illustrate the capability of a low-fidelity one-dimensional two-fluid model in predicting relevant flow parameters in two-phase particulate systems accurately even under flow regimes involving counter-current flow.

  11. Revisiting low-fidelity two-fluid models for gas-solids transport

    Science.gov (United States)

    Adeleke, Najeem; Adewumi, Michael; Ityokumbul, Thaddeus

    2016-08-01

    Two-phase gas-solids transport models are widely utilized for process design and automation in a broad range of industrial applications. Some of these applications include proppant transport in gaseous fracking fluids, air/gas drilling hydraulics, coal-gasification reactors and food processing units. Systems automation and real time process optimization stand to benefit a great deal from availability of efficient and accurate theoretical models for operations data processing. However, modeling two-phase pneumatic transport systems accurately requires a comprehensive understanding of gas-solids flow behavior. In this study we discuss the prevailing flow conditions and present a low-fidelity two-fluid model equation for particulate transport. The model equations are formulated in a manner that ensures the physical flux term remains conservative despite the inclusion of solids normal stress through the empirical formula for modulus of elasticity. A new set of Roe-Pike averages are presented for the resulting strictly hyperbolic flux term in the system of equations, which was used to develop a Roe-type approximate Riemann solver. The resulting scheme is stable regardless of the choice of flux-limiter. The model is evaluated by the prediction of experimental results from both pneumatic riser and air-drilling hydraulics systems. We demonstrate the effect and impact of numerical formulation and choice of numerical scheme on model predictions. We illustrate the capability of a low-fidelity one-dimensional two-fluid model in predicting relevant flow parameters in two-phase particulate systems accurately even under flow regimes involving counter-current flow.

  12. Decision support models for solid waste management: Review and game-theoretic approaches

    International Nuclear Information System (INIS)

    Karmperis, Athanasios C.; Aravossis, Konstantinos; Tatsiopoulos, Ilias P.; Sotirchos, Anastasios

    2013-01-01

    Highlights: ► The mainly used decision support frameworks for solid waste management are reviewed. ► The LCA, CBA and MCDM models are presented and their strengths, weaknesses, similarities and possible combinations are analyzed. ► The game-theoretic approach in a solid waste management context is presented. ► The waste management bargaining game is introduced as a specific decision support framework. ► Cooperative and non-cooperative game-theoretic approaches to decision support for solid waste management are discussed. - Abstract: This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost–benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as well as their critical issues are analyzed, while their possible combinations and extensions are also discussed. Furthermore, the paper presents how cooperative and non-cooperative game-theoretic approaches can be used for the purpose of modeling and analyzing decision-making in situations with multiple stakeholders. Specifically, since a waste management model is sustainable when considering not only environmental and economic but also social aspects, the waste management bargaining game is introduced as a specific decision support framework in which future models can be developed

  13. Decision support models for solid waste management: Review and game-theoretic approaches

    Energy Technology Data Exchange (ETDEWEB)

    Karmperis, Athanasios C., E-mail: athkarmp@mail.ntua.gr [Sector of Industrial Management and Operational Research, School of Mechanical Engineering, National Technical University of Athens, Iroon Polytechniou 9, 15780 Athens (Greece); Army Corps of Engineers, Hellenic Army General Staff, Ministry of Defence (Greece); Aravossis, Konstantinos; Tatsiopoulos, Ilias P.; Sotirchos, Anastasios [Sector of Industrial Management and Operational Research, School of Mechanical Engineering, National Technical University of Athens, Iroon Polytechniou 9, 15780 Athens (Greece)

    2013-05-15

    Highlights: ► The mainly used decision support frameworks for solid waste management are reviewed. ► The LCA, CBA and MCDM models are presented and their strengths, weaknesses, similarities and possible combinations are analyzed. ► The game-theoretic approach in a solid waste management context is presented. ► The waste management bargaining game is introduced as a specific decision support framework. ► Cooperative and non-cooperative game-theoretic approaches to decision support for solid waste management are discussed. - Abstract: This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost–benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as well as their critical issues are analyzed, while their possible combinations and extensions are also discussed. Furthermore, the paper presents how cooperative and non-cooperative game-theoretic approaches can be used for the purpose of modeling and analyzing decision-making in situations with multiple stakeholders. Specifically, since a waste management model is sustainable when considering not only environmental and economic but also social aspects, the waste management bargaining game is introduced as a specific decision support framework in which future models can be developed.

  14. Development and integration of modern laboratories in aerospace education

    Science.gov (United States)

    Desautel, D.; Hunter, N.; Mourtos, N.; Pernicka, H.

    1992-01-01

    This paper describes the development and integration of a suite of laboratories in an aerospace engineering program. The program's approach to undergraduate education is described as the source for the development of the supporting laboratories. Nine laboratories supporting instruction were developed and installed. The nine laboratories include most major flight-vehicle disciplines. The purpose and major equipments/experiments of each laboratory are briefly described, as is the integration of the laboratory with coursework. The laboratory education provided by this program successfully achieves its purpose of producing competitive aerospace engineering graduates and advancing the level of undergraduate education.

  15. Applications of aerospace technology to petroleum extraction and reservoir engineering

    Science.gov (United States)

    Jaffe, L. D.; Back, L. H.; Berdahl, C. M.; Collins, E. E., Jr.; Gordon, P. G.; Houseman, J.; Humphrey, M. F.; Hsu, G. C.; Ham, J. D.; Marte, J. E.; hide

    1977-01-01

    Through contacts with the petroleum industry, the petroleum service industry, universities and government agencies, important petroleum extraction problems were identified. For each problem, areas of aerospace technology that might aid in its solution were also identified, where possible. Some of the problems were selected for further consideration. Work on these problems led to the formulation of specific concepts as candidate for development. Each concept is addressed to the solution of specific extraction problems and makes use of specific areas of aerospace technology.

  16. Model study on transesterification of soybean oil to biodiesel with methanol using solid base catalyst.

    Science.gov (United States)

    Liu, Xuejun; Piao, Xianglan; Wang, Yujun; Zhu, Shenlin

    2010-03-25

    Modeling of the transesterification of vegetable oils to biodiesel using a solid base as a catalyst is very important because the mutual solubilities of oil and methanol will increase with the increasing biodiesel yield. The heterogeneous liquid-liquid-solid reaction system would become a liquid-solid system when the biodiesel reaches a certain content. In this work, we adopted a two-film theory and a steady state approximation assumption, then established a heterogeneous liquid-liquid-solid model in the first stage. After the diffusion coefficients on the liquid-liquid interface and the liquid-solid interface were calculated on the basis of the properties of the system, the theoretical value of biodiesel productivity changing with time was obtained. The predicted values were very near the experimental data, which indicated that the proposed models were suitable for the transesterification of soybean oil to biodiesel when solid bases were used as catalysts. Meanwhile, the model indicated that the transesterification reaction was controlled by both mass transfer and reaction. The total resistance will decrease with the increase in biodiesel yield in the liquid-liquid-solid stage. The solid base catalyst exhibited an activation energy range of 9-20 kcal/mol, which was consistent with the reported activation energy range of homogeneous catalysts.

  17. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 1: The value of scientific and technical information (STI), its relationship to Research and Development (R/D), and its use by US aerospace engineers and scientists

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Glassman, Myron; Oliu, Walter E.

    1990-01-01

    This paper is based on the premise that scientific and technical information (STI), its use by aerospace engineers and scientists, and the aerospace research and development (R&D) process are related. We intend to support this premise with data gathered from numerous studies concerned with STI, the relationship of STI to the performance and management of R&D activities, and the information use and seeking behavior of engineers in general and aerospace engineers and scientists in particular. We intend to develop and present a synthesized appreciation of how aerospace R&D managers can improve the efficacy of the R&D process by understanding the role and value of STI in this process.

  18. Solid Propellant Subscale Burning Rate Analysis Methods for US and Selected NATO Facilities

    Science.gov (United States)

    2002-01-01

    impossibility of the center of a particle lying closer than its radius from a solid boundary, * Due to surface tension and sedimentation (tends to level...34 effect (for bottom cast or bayonet cast grains) may consist of sedimentation of larger particles against the walls during casting flow, with the...February 2000. 91 Ratti A., "Metodi di Riduzione Dati Balistici per i Boosters a Propellente Solido di Ariane-4 e di Ariane-5," M.Sc. Thesis in Aerospace

  19. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 38: Computer Mediated Communication (CMC) and the communication of technical information in aerospace

    Science.gov (United States)

    Murphy, Daniel J.; Pinelli, Thomas E.

    1994-01-01

    This paper discusses the use of computers as a medium for communication (CMC) used by aerospace engineers and scientists to obtain and/or provide technical information related to research and development activities. The data were obtained from a questionnaire survey that yielded 1006 mail responses. In addition to communication media, the research also investigates degrees of task uncertainty, environmental complexity, and other relevant variables that can affect aerospace workers' information-seeking strategies. While findings indicate that many individuals report CMC is an important function in their communication patterns, the research indicates that CMC is used less often and deemed less valuable than other more conventional media, such as paper documents, group meetings, telephone and face-to-face conversations. Fewer than one third of the individuals in the survey account for nearly eighty percent of the reported CMC use, and another twenty percent indicate they do not use the medium at all, its availability notwithstanding. These preliminary findings suggest that CMC is not as pervasive a communication medium among aerospace workers as the researcher expect a priori. The reasons underlying the reported media use are not yet fully known, and this suggests that continuing research in this area may be valuable.

  20. Experimental validation of solid rocket motor damping models

    Science.gov (United States)

    Riso, Cristina; Fransen, Sebastiaan; Mastroddi, Franco; Coppotelli, Giuliano; Trequattrini, Francesco; De Vivo, Alessio

    2017-12-01

    In design and certification of spacecraft, payload/launcher coupled load analyses are performed to simulate the satellite dynamic environment. To obtain accurate predictions, the system damping properties must be properly taken into account in the finite element model used for coupled load analysis. This is typically done using a structural damping characterization in the frequency domain, which is not applicable in the time domain. Therefore, the structural damping matrix of the system must be converted into an equivalent viscous damping matrix when a transient coupled load analysis is performed. This paper focuses on the validation of equivalent viscous damping methods for dynamically condensed finite element models via correlation with experimental data for a realistic structure representative of a slender launch vehicle with solid rocket motors. A second scope of the paper is to investigate how to conveniently choose a single combination of Young's modulus and structural damping coefficient—complex Young's modulus—to approximate the viscoelastic behavior of a solid propellant material in the frequency band of interest for coupled load analysis. A scaled-down test article inspired to the Z9-ignition Vega launcher configuration is designed, manufactured, and experimentally tested to obtain data for validation of the equivalent viscous damping methods. The Z9-like component of the test article is filled with a viscoelastic material representative of the Z9 solid propellant that is also preliminarily tested to investigate the dependency of the complex Young's modulus on the excitation frequency and provide data for the test article finite element model. Experimental results from seismic and shock tests performed on the test configuration are correlated with numerical results from frequency and time domain analyses carried out on its dynamically condensed finite element model to assess the applicability of different equivalent viscous damping methods to describe

  1. Experimental validation of solid rocket motor damping models

    Science.gov (United States)

    Riso, Cristina; Fransen, Sebastiaan; Mastroddi, Franco; Coppotelli, Giuliano; Trequattrini, Francesco; De Vivo, Alessio

    2018-06-01

    In design and certification of spacecraft, payload/launcher coupled load analyses are performed to simulate the satellite dynamic environment. To obtain accurate predictions, the system damping properties must be properly taken into account in the finite element model used for coupled load analysis. This is typically done using a structural damping characterization in the frequency domain, which is not applicable in the time domain. Therefore, the structural damping matrix of the system must be converted into an equivalent viscous damping matrix when a transient coupled load analysis is performed. This paper focuses on the validation of equivalent viscous damping methods for dynamically condensed finite element models via correlation with experimental data for a realistic structure representative of a slender launch vehicle with solid rocket motors. A second scope of the paper is to investigate how to conveniently choose a single combination of Young's modulus and structural damping coefficient—complex Young's modulus—to approximate the viscoelastic behavior of a solid propellant material in the frequency band of interest for coupled load analysis. A scaled-down test article inspired to the Z9-ignition Vega launcher configuration is designed, manufactured, and experimentally tested to obtain data for validation of the equivalent viscous damping methods. The Z9-like component of the test article is filled with a viscoelastic material representative of the Z9 solid propellant that is also preliminarily tested to investigate the dependency of the complex Young's modulus on the excitation frequency and provide data for the test article finite element model. Experimental results from seismic and shock tests performed on the test configuration are correlated with numerical results from frequency and time domain analyses carried out on its dynamically condensed finite element model to assess the applicability of different equivalent viscous damping methods to describe

  2. Engineers as Information Processors: A Survey of US Aerospace Engineering Faculty and Students.

    Science.gov (United States)

    Holland, Maurita Peterson; And Others

    1991-01-01

    Reports on survey results from 275 faculty and 640 students, predominantly in the aerospace engineering field, concerning their behaviors about the appropriation and dissemination of information. Indicates that, as information processors, aerospace faculty and students are "information naive." Raises questions about the efficacy of…

  3. Integrated models for solid waste management in tourism regions: Langkawi Island, Malaysia.

    Science.gov (United States)

    Shamshiry, Elmira; Nadi, Behzad; Mokhtar, Mazlin Bin; Komoo, Ibrahim; Hashim, Halimaton Saadiah; Yahaya, Nadzri

    2011-01-01

    The population growth, changing consumption patterns, and rapid urbanization contribute significantly to the growing volumes of solid waste that are generated in urban settings. As the rate of urbanization increases, demand on the services of solid waste management increases. The rapid urban growth in Langkawi Island, Malaysia, combined with the increasing rates of solid waste production has provided evidence that the traditional solid waste management practices, particularly the methods of waste collection and disposal, are inefficient and quite nonsustainable. Accordingly, municipal managers and planners in Langkawi need to look for and adopt a model for solid waste management that emphasizes an efficient and sustainable management of solid wastes in Langkawi Island. This study presents the current practices of solid waste management in Langkawi Island, describes the composition of the solid waste generated in that area, and presents views of local residents and tourist on issues related to solid waste management like the aesthetic value of the island environment. The most important issue of this paper is that it is the first time that integrated solid waste management is investigated in the Langkawi Island.

  4. Modelling of fluid-solid interaction using two stand-alone codes

    CSIR Research Space (South Africa)

    Grobler, Jan H

    2010-01-01

    Full Text Available A method is proposed for the modelling of fluid-solid interaction in applications where fluid forces dominate. Data are transferred between two stand-alone codes: a dedicated computational fluid dynamics (CFD) code capable of free surface modelling...

  5. Predictive model to describe water migration in cellular solid foods during storage

    NARCIS (Netherlands)

    Voogt, J.A.; Hirte, A.; Meinders, M.B.J.

    2011-01-01

    BACKGROUND: Water migration in cellular solid foods during storage causes loss of crispness. To improve crispness retention, physical understanding of this process is needed. Mathematical models are suitable tools to gain this physical knowledge. RESULTS: Water migration in cellular solid foods

  6. Predictive model to describe water migration in cellular solid foods during storage

    NARCIS (Netherlands)

    Voogt, J.A.; Hirte, A.; Meinders, M.B.J.

    2011-01-01

    Background: Water migration in cellular solid foods during storage causes loss of crispness. To improve crispness retention, physical understanding of this process is needed. Mathematical models are suitable tools to gain this physical knowledge. Results: Water migration in cellular solid foods

  7. The Relationship between Organizational Culture Types and Innovation in Aerospace Companies

    Science.gov (United States)

    Nelson, Adaora N.

    Innovation in the aerospace industry has proven to be an effective strategy for competitiveness and sustainability. The organizational culture of the firm must be conducive to innovation. The problem was that although innovation is needed for aerospace companies to be competitive and sustainable, certain organizational culture issues might hinder leaders from successfully innovating (Emery, 2010; Ramanigopal, 2012). The purpose of this study was to assess the relationship of hierarchical, clan, adhocracy and market organizational types and innovation in aerospace companies within the U.S while controlling for company size and length of time in business. The non-experimental quantitative study included a random sample of 136 aerospace leaders in the U.S. There was a significant relationship between market organizational culture and innovation, F(1,132) = 4.559, p = .035. No significant relationships were found between hierarchical organizational culture and innovation and between clan culture and innovation. The relationship between adhocracy culture and innovation was not significant, possible due to inadequate sample size. Company size was shown to be a justifiable covariate in the study, due to a significant relationship with innovative (F(1, 130) = 4.66, p business had no relationship with innovation. The findings imply that market organizational cultures are more likely to result in innovative outcomes in the aerospace industry. Organizational leaders are encouraged to adopt a market culture and adopt smaller organizational structures. Recommendations for further research include investigating the relationship between adhocracy culture and innovation using an adequate sample size. Research is needed to determine other variables that predict innovation. This study should be repeated at periodic intervals and across other industrial sectors and countries.

  8. Computer-aided design model for anaerobic-phased-solids digester system

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z.; Zhang, R. [University of California, Davis, CA (United States); Tiangco, V. [California Energy Commission, Sacramento, CA (United States)

    1999-07-01

    The anaerobic-phased-solids (APS) digester system is a newly developed anaerobic digestion system for converting solid wastes, such as crop residues and food wastes, into biogas for power and heat generation. A computer-aided engineering design model has been developed to design the APS-digester system and study the heat transfer from the reactors and energy production of the system. Simulation results of a case study are presented by using the model to predict the heating energy requirement and biogas energy production for anaerobic digestion of garlic waste. The important factors, such as environmental conditions, insulation properties, and characteristics of the wastes, on net energy production are also investigated. (author)

  9. Water recovery and solid waste processing for aerospace and domestic applications. Volume 2: Appendices

    Science.gov (United States)

    Murray, R. W.

    1973-01-01

    Water and sewage treatment systems are presented with concentration on the filtration of water. Equipment is described for organic removal, solids removal, nutrient removal, inorganic removal, and disinfection of the water. Such things as aseline hardware, additional piping connections, waste disposal, and costs involved are also reported.

  10. Aerospace Communications Technologies in Support of NASA Mission

    Science.gov (United States)

    Miranda, Felix A.

    2016-01-01

    NASA is endeavoring in expanding communications capabilities to enable and enhance robotic and human exploration of space and to advance aero communications here on Earth. This presentation will discuss some of the research and technology development work being performed at the NASA Glenn Research Center in aerospace communications in support of NASAs mission. An overview of the work conducted in-house and in collaboration with academia, industry, and other government agencies (OGA) to advance radio frequency (RF) and optical communications technologies in the areas of antennas, ultra-sensitive receivers, power amplifiers, among others, will be presented. In addition, the role of these and other related RF and optical communications technologies in enabling the NASA next generation aerospace communications architecture will be also discussed.

  11. Solid Waste Projection Model: Database (Version 1.4)

    International Nuclear Information System (INIS)

    Blackburn, C.; Cillan, T.

    1993-09-01

    The Solid Waste Projection Model (SWPM) system is an analytical tool developed by Pacific Northwest Laboratory (PNL) for Westinghouse Hanford Company (WHC). The SWPM system provides a modeling and analysis environment that supports decisions in the process of evaluating various solid waste management alternatives. This document, one of a series describing the SWPM system, contains detailed information regarding the software and data structures utilized in developing the SWPM Version 1.4 Database. This document is intended for use by experienced database specialists and supports database maintenance, utility development, and database enhancement. Those interested in using the SWPM database should refer to the SWPM Database User's Guide. This document is available from the PNL Task M Project Manager (D. L. Stiles, 509-372-4358), the PNL Task L Project Manager (L. L. Armacost, 509-372-4304), the WHC Restoration Projects Section Manager (509-372-1443), or the WHC Waste Characterization Manager (509-372-1193)

  12. LG Solid Oxide Fuel Cell (SOFC) Model Development

    Energy Technology Data Exchange (ETDEWEB)

    Haberman, Ben [LG Fuel Cell Systems Inc., North Canton, OH (United States); Martinez-Baca, Carlos [LG Fuel Cell Systems Inc., North Canton, OH (United States); Rush, Greg [LG Fuel Cell Systems Inc., North Canton, OH (United States)

    2013-05-31

    This report presents a summary of the work performed by LG Fuel Cell Systems Inc. during the project LG Solid Oxide Fuel Cell (SOFC) Model Development (DOE Award Number: DE-FE0000773) which commenced on October 1, 2009 and was completed on March 31, 2013. The aim of this project is for LG Fuel Cell Systems Inc. (formerly known as Rolls-Royce Fuel Cell Systems (US) Inc.) (LGFCS) to develop a multi-physics solid oxide fuel cell (SOFC) computer code (MPC) for performance calculations of the LGFCS fuel cell structure to support fuel cell product design and development. A summary of the initial stages of the project is provided which describes the MPC requirements that were developed and the selection of a candidate code, STAR-CCM+ (CD-adapco). This is followed by a detailed description of the subsequent work program including code enhancement and model verification and validation activities. Details of the code enhancements that were implemented to facilitate MPC SOFC simulations are provided along with a description of the models that were built using the MPC and validated against experimental data. The modeling work described in this report represents a level of calculation detail that has not been previously available within LGFCS.

  13. Solid waste integrated cost analysis model: 1991 project year report. Part 2

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    The purpose of the City of Houston`s 1991 Solid Waste Integrated Cost Analysis Model (SWICAM) project was to continue the development of a computerized cost analysis model. This model is to provide solid waste managers with tool to evaluate the dollar cost of real or hypothetical solid waste management choices. Those choices have become complicated by the implementation of Subtitle D of the Resources Conservation and Recovery Act (RCRA) and the EPA`s Integrated Approach to managing municipal solid waste;. that is, minimize generation, maximize recycling, reduce volume (incinerate), and then bury (landfill) only the remainder. Implementation of an integrated solid waste management system involving all or some of the options of recycling, waste to energy, composting, and landfilling is extremely complicated. Factors such as hauling distances, markets, and prices for recyclable, costs and benefits of transfer stations, and material recovery facilities must all be considered. A jurisdiction must determine the cost impacts of implementing a number of various possibilities for managing, handling, processing, and disposing of waste. SWICAM employs a single Lotus 123 spreadsheet to enable a jurisdiction to predict or assess the costs of its waste management system. It allows the user to select his own process flow for waste material and to manipulate the model to include as few or as many options as he or she chooses. The model will calculate the estimated cost for those choices selected. The user can then change the model to include or exclude waste stream components, until the mix of choices suits the user. Graphs can be produced as a visual communication aid in presenting the results of the cost analysis. SWICAM also allows future cost projections to be made.

  14. FPGAs and parallel architectures for aerospace applications soft errors and fault-tolerant design

    CERN Document Server

    Rech, Paolo

    2016-01-01

    This book introduces the concepts of soft errors in FPGAs, as well as the motivation for using commercial, off-the-shelf (COTS) FPGAs in mission-critical and remote applications, such as aerospace.  The authors describe the effects of radiation in FPGAs, present a large set of soft-error mitigation techniques that can be applied in these circuits, as well as methods for qualifying these circuits under radiation.  Coverage includes radiation effects in FPGAs, fault-tolerant techniques for FPGAs, use of COTS FPGAs in aerospace applications, experimental data of FPGAs under radiation, FPGA embedded processors under radiation, and fault injection in FPGAs. Since dedicated parallel processing architectures such as GPUs have become more desirable in aerospace applications due to high computational power, GPU analysis under radiation is also discussed. ·         Discusses features and drawbacks of reconfigurability methods for FPGAs, focused on aerospace applications; ·         Explains how radia...

  15. Analysis and Modeling of Structure Formation in Granular and Fluid-Solid Flows

    Science.gov (United States)

    Murphy, Eric

    Granular and multiphase flows are encountered in a number of industrial processes with particular emphasis in this manuscript given to the particular applications in cement pumping, pneumatic conveying, fluid catalytic cracking, CO2 capture, and fast pyrolysis of bio-materials. These processes are often modeled using averaged equations that may be simulated using computational fluid dynamics. Closure models are then required that describe the average forces that arise from both interparticle interactions, e.g. shear stress, and interphase interactions, such as mean drag. One of the biggest hurdles to this approach is the emergence of non-trivial spatio-temporal structures in the particulate phase, which can significantly modify the qualitative behavior of these forces and the resultant flow phenomenology. For example, the formation of large clusters in cohesive granular flows is responsible for a transition from solid-like to fluid-like rheology. Another example is found in gas-solid systems, where clustering at small scales is observed to significantly lower in the observed drag. Moreover, there remains the possibility that structure formation may occur at all scales, leading to a lack of scale separation required for traditional averaging approaches. In this context, several modeling problems are treated 1) first-principles based modeling of the rheology of cement slurries, 2) modeling the mean solid-solid drag experienced by polydisperse particles undergoing segregation, and 3) modeling clustering in homogeneous gas-solid flows. The first and third components are described in greater detail. In the study on the rheology of cements, several sub-problems are introduced, which systematically increase in the number and complexity of interparticle interactions. These interparticle interactions include inelasticity, friction, cohesion, and fluid interactions. In the first study, the interactions between cohesive inelastic particles was fully characterized for the

  16. A simple model for low energy ion-solid interactions

    International Nuclear Information System (INIS)

    Mohajerzadeh, S.; Selvakumar, C.R.

    1997-01-01

    A simple analytical model for ion-solid interactions, suitable for low energy beam depositions, is reported. An approximation for the nuclear stopping power is used to obtain the analytic solution for the deposited energy in the solid. The ratio of the deposited energy in the bulk to the energy deposited in the surface yields a ceiling for the beam energy above which more defects are generated in the bulk resulting in defective films. The numerical evaluations agree with the existing results in the literature. copyright 1997 American Institute of Physics

  17. Modeling Dissolved Solids in the Rincon Valley, New Mexico Using RiverWare

    Science.gov (United States)

    Abudu, S.; Ahn, S. R.; Sheng, Z.

    2017-12-01

    Simulating transport and storage of dissolved solids in surface water and underlying alluvial aquifer is essential to evaluate the impacts of surface water operations, groundwater pumping, and climate variability on the spatial and temporal variability of salinity in the Rio Grande Basin. In this study, we developed a monthly RiverWare water quantity and quality model to simulate the both concentration and loads of dissolved solids for the Rincon Valley, New Mexico from Caballo Reservoir to Leasburg Dam segment of the Rio Grande. The measured flows, concentration and loads of dissolved solids in the main stream and drains were used to develop RiveWare model using 1980-1988 data for calibration, and 1989-1995 data for validation. The transport of salt is tracked using discretized salt and post-process approaches. Flow and salt exchange between the surface water and adjacent groundwater objects is computed using "soil moisture salt with supplemental flow" method in the RiverWare. In the groundwater objects, the "layered salt" method is used to simulate concentration of the dissolved solids in the shallow groundwater storage. In addition, the estimated local inflows under different weather conditions by using a calibrated Soil Water Assessment Tool (SWAT) were fed into the RiverWare to refine the simulation of the flow and dissolved solids. The results show the salt concentration and loads increased at Leasburg Dam, which indicates the river collects salts from the agricultural return flow and the underlying aquifer. The RiverWare model with the local inflow fed by SWAT delivered the better quantification of temporal and spatial salt exchange patterns between the river and the underlying aquifer. The results from the proposed modeling approach can be used to refine the current mass-balance budgets for dissolved-solids transport in the Rio Grande, and provide guidelines for planning and decision-making to control salinity in arid river environment.

  18. The effect of generation on retention of women engineers in aerospace and industry

    Science.gov (United States)

    Kiernan, Kristine Maria

    The purpose of this dissertation was to determine the nature and extent of differences between generational cohorts regarding the effect of family factors on retention of women in engineering, with an emphasis on women in the aerospace industry. While 6% of the aerospace workforce is made up of aeronautical engineers, an additional 11.2% of the aerospace workforce is drawn from other engineering disciplines. Therefore, the analysis included all engineering sub-disciplines. In order to include women who had left the workforce, women in all industries were used as a proxy for women in aerospace. Exits to other fields were modeled separately from exits out of the workforce. The source of data was the National Survey of College Graduates. Women engineers were divided into the Baby Boom cohort (born 1945-1964), the Generation X cohort (born 1965-1980), and the Millennial cohort (born 1981-1997). A time-lag design was used to compare generational cohorts when they were the same age. The results of this study showed that generational cohort did not affect retention of women in engineering. However, generational cohort affected family formation decisions, with Millennial women marrying and having children later than their counterparts in the Generation X and Baby Boom cohorts. Generational cohort also affected the influence of motherhood on retention in the workforce, with Generation X and Millennial mothers more likely to stay in the workforce than their counterparts in the Baby Boom cohort. There was no significant difference between Generation X and Millennial women in the proportion of mothers who stayed in the workforce. Generational cohort influenced the reasons women left the workforce. Women in the Millennial cohort were more likely to cite not needing or wanting to work, while women in the Generation X cohort were more likely to cite family responsibilities. Among mothers in the Millennial cohort who were out of the workforce, the proportion who cited not needing

  19. Improving Aerospace Engineering Students' Achievements by an Open Aero Control Experiment Apparatus

    Science.gov (United States)

    Zeng, QingHua; Zhang, WeiHua; Huang, ZheZhi; Dong, RongHua

    2014-01-01

    This paper describes the development of an aero control experiment apparatus (ACEA) for use in aerospace control practical courses. The ACEA incorporates a systematic multihierarchy learning and teaching method, and was designed to improve aerospace engineering students' understanding of unmanned aerial vehicle (UAV) control systems. It offers a…

  20. Communication for performance in aerospace

    Directory of Open Access Journals (Sweden)

    Aurelian Virgil BALUTA

    2016-12-01

    Full Text Available The paper outlines rules for employees in the aerospace field about general procedures, accounting, budgets, employees involvement in the companies goals as a team or as a group. The quality of all communications activities is presented in correlation with performance. For us, performance means economic and social references, stability and credibility of the business and, not least, a good communication within the existing groups or teams. We take in account long-term, medium and short performance for a new and modern field such as the aerospace industry. The paper highlights the group communication aspects, the process needed to optimize communication within a group, the team characteristics and mission, the team involvement versus group involvement, organization of the work team and defining/definition of roles in a team according to individual skills and some technics; to apply the Belbin test for determining the role of individuals within the team, for identifying the types of communication in order to get the information transmitted to the different types of individuals such as “analytical type”, “director type”, “friendly type”, “expressive type”, the needs and interest of these individuals, assessing how the information was received and the impact of the feedback.

  1. Rheo-processing of semi-solid metal alloys: a new technology for manufacturing Automotive and aerospace components - Conference paper

    CSIR Research Space (South Africa)

    Ivanchev, L

    2006-02-01

    Full Text Available -solid forming processes. The CSIR in SA, developed and patented a rheocasting process and equipment for semi solid casting, which is in the commercialization stage and an automotive component will be manufactured soon....

  2. Modeling of vapor-liquid-solid equilibrium in gas - aqueous electrolyte systems

    DEFF Research Database (Denmark)

    Thomsen, Kaj; Rasmussen, Peter

    1999-01-01

    A thermodynamic model for the description of vapor-liquid-solid equilibria is introduced. This model is a combination of the extended UNIQUAC model for electrolytes and the Soave-Redlich-Kwong cubic equation of state. The model has been applied to aqueous systems containing ammonia and/or carbon ...

  3. Space modeling with SolidWorks and NX

    CERN Document Server

    Duhovnik, Jože; Drešar, Primož

    2015-01-01

    Through a series of step-by-step tutorials and numerous hands-on exercises, this book aims to equip the reader with both a good understanding of the importance of space in the abstract world of engineers and the ability to create a model of a product in virtual space – a skill essential for any designer or engineer who needs to present ideas concerning a particular product within a professional environment. The exercises progress logically from the simple to the more complex; while SolidWorks or NX is the software used, the underlying philosophy is applicable to all modeling software. In each case, the explanation covers the entire procedure from the basic idea and production capabilities through to the real model; the conversion from 3D model to 2D manufacturing drawing is also clearly explained. Topics covered include modeling of prism, axisymmetric, symmetric, and sophisticated shapes; digitization of physical models using modeling software; creation of a CAD model starting from a physical model; free fo...

  4. Multi-solid and multi-fluid diffuse interface model: Applications to dynamic fracture and fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Ndanou, S., E-mail: serge.ndanou@univ-amu.fr; Favrie, N., E-mail: nicolas.favrie@univ-amu.fr; Gavrilyuk, S., E-mail: sergey.gavrilyuk@univ-amu.fr

    2015-08-15

    We extend the model of diffuse solid–fluid interfaces developed earlier by authors of this paper to the case of arbitrary number of interacting hyperelastic solids. Plastic transformations of solids are taken into account through a Maxwell type model. The specific energy of each solid is given in separable form: it is the sum of a hydrodynamic part of the energy depending only on the density and the entropy, and an elastic part of the energy which is unaffected by the volume change. It allows us to naturally pass to the fluid description in the limit of vanishing shear modulus. In spite of a large number of governing equations, the model has a quite simple mathematical structure: it is a duplication of a single visco-elastic model. The model is well posed both mathematically and thermodynamically: it is hyperbolic and compatible with the second law of thermodynamics. The resulting model can be applied in the situations involving an arbitrary number of fluids and solids. In particular, we show the ability of the model to describe spallation and penetration phenomena occurring during high velocity impacts.

  5. Finite element modeling for integrated solid-solid PCM-building material with varying phase change temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, D.; Fung, A.S.; Siddiqui, O. [Ryerson Polytechnic Univ., Toronto, ON (Canada). Dept. of Mechanical and Industrial Engineering

    2008-08-15

    Solid-solid phase change materials (SSPCMs) are used to enhance thermal storage performance and reduce indoor temperature fluctuations in buildings. In this study, a finite element model (FEM) was used to investigate the thermal properties of different types of SSPCMs. An effective heat capacity method was used to develop the model. An integrated PCM-building material was analyzed in relation to temperature and heat flux profiles. Governing equations for the heat transfer process were composed of Navier-Stokes momentum equations; a mass conservation equation; and an energy conservation equation. Effective heat capacity was described as a linear function of the latent heat of fusion on both the heating and cooling processes. Data from the simulation were then compared with an experiment suing drywall, concrete and gypcrete samples. Heat flux across the surfaces and temperatures on the surfaces of the materials were measured. Data were used to validate the finite element model (FEM). Results of the study suggested that heat flux profiles are an effective means of understanding phase change processes. It was concluded that PCMs with lower phase change temperatures lengthened energy releases and improved thermal comfort in the building. 12 refs., 2 tabs., 14 figs.

  6. Integrated Models for Solid Waste Management in Tourism Regions: Langkawi Island, Malaysia

    Directory of Open Access Journals (Sweden)

    Elmira Shamshiry

    2011-01-01

    Full Text Available The population growth, changing consumption patterns, and rapid urbanization contribute significantly to the growing volumes of solid waste that are generated in urban settings. As the rate of urbanization increases, demand on the services of solid waste management increases. The rapid urban growth in Langkawi Island, Malaysia, combined with the increasing rates of solid waste production has provided evidence that the traditional solid waste management practices, particularly the methods of waste collection and disposal, are inefficient and quite nonsustainable. Accordingly, municipal managers and planners in Langkawi need to look for and adopt a model for solid waste management that emphasizes an efficient and sustainable management of solid wastes in Langkawi Island. This study presents the current practices of solid waste management in Langkawi Island, describes the composition of the solid waste generated in that area, and presents views of local residents and tourist on issues related to solid waste management like the aesthetic value of the island environment. The most important issue of this paper is that it is the first time that integrated solid waste management is investigated in the Langkawi Island.

  7. Integrated Models for Solid Waste Management in Tourism Regions: Langkawi Island, Malaysia

    Science.gov (United States)

    Shamshiry, Elmira; Nadi, Behzad; Bin Mokhtar, Mazlin; Komoo, Ibrahim; Saadiah Hashim, Halimaton; Yahaya, Nadzri

    2011-01-01

    The population growth, changing consumption patterns, and rapid urbanization contribute significantly to the growing volumes of solid waste that are generated in urban settings. As the rate of urbanization increases, demand on the services of solid waste management increases. The rapid urban growth in Langkawi Island, Malaysia, combined with the increasing rates of solid waste production has provided evidence that the traditional solid waste management practices, particularly the methods of waste collection and disposal, are inefficient and quite nonsustainable. Accordingly, municipal managers and planners in Langkawi need to look for and adopt a model for solid waste management that emphasizes an efficient and sustainable management of solid wastes in Langkawi Island. This study presents the current practices of solid waste management in Langkawi Island, describes the composition of the solid waste generated in that area, and presents views of local residents and tourist on issues related to solid waste management like the aesthetic value of the island environment. The most important issue of this paper is that it is the first time that integrated solid waste management is investigated in the Langkawi Island. PMID:21904559

  8. Exploring Stakeholder Definitions within the Aerospace Industry: A Qualitative Case Study

    Science.gov (United States)

    Hebert, Jonathan R.

    A best practice in the discipline of project management is to identify all key project stakeholders prior to the execution of a project. When stakeholders are properly identified, they can be consulted to provide expert advice on project activities so that the project manager can ensure the project stays within the budget and schedule constraints. The problem addressed by this study is that managers fail to properly identify key project stakeholders when using stakeholder theory because there are multiple conflicting definitions for the term stakeholder. Poor stakeholder identification has been linked to multiple negative project outcomes such as budget and schedules overruns, and this problem is heightened in certain industries such as aerospace. The purpose of this qualitative study was to explore project managers' and project stakeholders' perceptions of how they define and use the term stakeholder within the aerospace industry. This qualitative exploratory single-case study had two embedded units of analysis: project managers and project stakeholders. Six aerospace project managers and five aerospace project stakeholders were purposively selected for this study. Data were collected through individual semi-structured interviews with both project managers and project stakeholders. All data were analyzed using Yin's (2011) five-phased cycle approach for qualitative research. The results indicated that the aerospace project managers and project stakeholder define the term stakeholder as "those who do the work of a company." The participants build upon this well-known concept by adding that, "a company should list specific job titles" that correspond to their company specific-stakeholder definition. Results also indicated that the definition of the term stakeholder is used when management is assigning human resources to a project to mitigate or control project risk. Results showed that project managers tended to include the customer in their stakeholder definitions

  9. Applying the competence-based approach to management in the aerospace industry

    OpenAIRE

    Arpentieva Mariam; Duvalina Olga; Braitseva Svetlana; Gorelova Irina; Rozhnova Anna

    2018-01-01

    Problems of management in aerospace manufacturing are similar to those we observe in other sectors, the main of which is the flattening of strategic management. The main reason lies in the attitude towards human resource of the organization. In the aerospace industry employs 250 thousand people, who need individual approach. The individual approach can offer competence-based approach to management. The purpose of the study is proof of the benefits of the competency approach to human resource ...

  10. The mix of laws involved in the activity of the companies in the aerospace field

    Directory of Open Access Journals (Sweden)

    Aurelian Virgil BALUTA

    2017-03-01

    Full Text Available The life of companies, including the aerospace companies, depends on the business cycle. The paper presents the trends of law in ascending and descending period of the business cycle. A point of the paper is the separation of military and civil law in aerospace, public and private law, national and corporate security systems. Also the laws to be apply in relation with public authorities, private organizations, citizens are approched. In the paper are included some keys for interpretation such as the hierarchy of social values. In modern times, the humans life, rights and property must be the main protected values. The paper shows the methods to be accepted for the analyse/analysis of law in aerospace field: logical analysis, hystorical method, comparative method, social research, experimental method. In the aerospace field each of them has some particularities. The classification of laws depending of economic impact in the aerospace field is an other section. There are presented implications on cost, income, receipts, payments, duration of the activities, other restrictions.

  11. Microfabricated Chemical Gas Sensors and Sensor Arrays for Aerospace Applications

    Science.gov (United States)

    Hunter, Gary W.

    2005-01-01

    Aerospace applications require the development of chemical sensors with capabilities beyond those of commercially available sensors. In particular, factors such as minimal sensor size, weight, and power consumption are particularly important. Development areas which have potential aerospace applications include launch vehicle leak detection, engine health monitoring, and fire detection. Sensor development for these applications is based on progress in three types of technology: 1) Micromachining and microfabrication (Microsystem) technology to fabricate miniaturized sensors; 2) The use of nanocrystalline materials to develop sensors with improved stability combined with higher sensitivity; 3) The development of high temperature semiconductors, especially silicon carbide. This presentation discusses the needs of space applications as well as the point-contact sensor technology and sensor arrays being developed to address these needs. Sensors to measure hydrogen, hydrocarbons, nitrogen oxides (NO,), carbon monoxide, oxygen, and carbon dioxide are being developed as well as arrays for leak, fire, and emissions detection. Demonstrations of the technology will also be discussed. It is concluded that microfabricated sensor technology has significant potential for use in a range of aerospace applications.

  12. On the Optimization of Aerospace Plane Ascent Trajectory

    Science.gov (United States)

    Al-Garni, Ahmed; Kassem, Ayman Hamdy

    A hybrid heuristic optimization technique based on genetic algorithms and particle swarm optimization has been developed and tested for trajectory optimization problems with multi-constraints and a multi-objective cost function. The technique is used to calculate control settings for two types for ascending trajectories (constant dynamic pressure and minimum-fuel-minimum-heat) for a two-dimensional model of an aerospace plane. A thorough statistical analysis is done on the hybrid technique to make comparisons with both basic genetic algorithms and particle swarm optimization techniques with respect to convergence and execution time. Genetic algorithm optimization showed better execution time performance while particle swarm optimization showed better convergence performance. The hybrid optimization technique, benefiting from both techniques, showed superior robust performance compromising convergence trends and execution time.

  13. Hierarchical Composites with Nanostructured Reinforcement for Multifunctional Aerospace Structures

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced nano-engineered composites hold great potential for augmenting aerospace composites material performance by reducing spacecraft weight, increasing payload...

  14. 78 FR 77501 - NASA Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2013-12-23

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice: 13-153] NASA Aerospace Safety Advisory Panel; Meeting AGENCY: National Aeronautics and Space Administration (NASA). ACTION: Notice of Meeting...

  15. Gibbs Energy Modeling of Digenite and Adjacent Solid-State Phases

    Science.gov (United States)

    Waldner, Peter

    2017-08-01

    All sulfur potential and phase diagram data available in the literature for solid-state equilibria related to digenite have been assessed. Thorough thermodynamic analysis at 1 bar total pressure has been performed. A three-sublattice approach has been developed to model the Gibbs energy of digenite as a function of composition and temperature using the compound energy formalism. The Gibbs energies of the adjacent solid-state phases covelitte and high-temperature chalcocite are also modeled treating both sulfides as stoichiometric compounds. The novel model for digenite offers new interpretation of experimental data, may contribute from a thermodynamic point of view to the elucidation of the role of copper species within the crystal structure and allows extrapolation to composition regimes richer in copper than stoichiometric digenite Cu2S. Preliminary predictions into the ternary Cu-Fe-S system at 1273 K (1000 °C) using the Gibbs energy model of digenite for calculating its iron solubility are promising.

  16. Curcumin-Artemisinin Coamorphous Solid: Xenograft Model Preclinical Study

    Directory of Open Access Journals (Sweden)

    M. K. Chaitanya Mannava

    2018-01-01

    Full Text Available Curcumin is a natural compound present in Indian spice turmeric. It has diverse pharmacological action but low oral solubility and bioavailability continue to limit its use as a drug. With the aim of improving the bioavailability of Curcumin (CUR, we evaluated Curcumin-Pyrogallol (CUR-PYR cocrystal and Curcumin-Artemisinin (CUR-ART coamorphous solid. Both of these solid forms exhibited superior dissolution and pharmacokinetic behavior compared to pure CUR, which is practically insoluble in water. CUR-ART coamorphous solid showed two fold higher bioavailability than CUR-PYR cocrystal (at 200 mg/kg oral dose. Moreover, in simulated gastric and intestinal fluids (SGF and SIF, CUR-ART is stable up to 3 and 12 h, respectively. In addition, CUR-PYR and CUR-ART showed no adverse effects in toxicology studies (10 times higher dose at 2000 mg/kg. CUR-ART showed higher therapeutic effect and inhibited approximately 62% of tumor growth at 100 mg/kg oral dosage of CUR in xenograft models, which is equal to the positive control drug, doxorubicin (2 mg/kg by i.v. administration.

  17. Mathematical model for solid fuel combustion in fluidized bed

    International Nuclear Information System (INIS)

    Kostikj, Zvonimir; Noshpal, Aleksandar

    1994-01-01

    A mathematical model for computation of the combustion process of solid fuel in fluidized bed is presented in this work. Only the combustor part of the plant (the fluidized bed and the free board) is treated with this model. In that manner, all principal, physical presumption and improvements (upon which this model is based) are given. Finally, the results of the numerical realisation of the mathematical model for combustion of minced straw as well as the results of the experimental investigation of a concrete physical model are presented. (author)

  18. Experimental Characterisation and Modelling of Homogeneous Solid Suspension in an Industrial Stirred Tank

    Directory of Open Access Journals (Sweden)

    Sébastien Calvo

    2013-01-01

    Full Text Available In this work, we study the conditions needed to reach homogeneous distribution of aluminium salts particles in water inside a torispherical bottom shaped stirred tank of 70 L equipped with a Pfaudler RCI type impeller and three equispaced vertical baffles. The aim of the present study is to develop a CFD model describing the quality of particle distribution in industrial scale tanks. This model, validated with experimental data, is used afterwards to develop scale-up and scale-down correlations to predict the minimum impeller speed needed to reach homogeneous solid distribution Nhs. The commercial CFD software Fluent 14 is used to model the fluid flow and the solid particle distribution in the tank. Sliding Mesh approach is used to take the impeller motion into account. Assuming that the discrete solid phase has no influence on the continuous liquid phase behaviour, the fluid flow dynamics is simulated independently using the well-known k-∊ turbulence model. The liquid-solid mixture behaviour is then described by implementing the Eulerian Mixture model. Computed liquid velocity fields are validated by comparison with PIV measurements. Computed Nhs were found to be in good agreement with experimental measurements. Results from different scales allowed correlating Nhs values to the volumetric power consumption.

  19. Co-digestion of solid waste: Towards a simple model to predict methane production.

    Science.gov (United States)

    Kouas, Mokhles; Torrijos, Michel; Schmitz, Sabine; Sousbie, Philippe; Sayadi, Sami; Harmand, Jérôme

    2018-04-01

    Modeling methane production is a key issue for solid waste co-digestion. Here, the effect of a step-wise increase in the organic loading rate (OLR) on reactor performance was investigated, and four new models were evaluated to predict methane yields using data acquired in batch mode. Four co-digestion experiments of mixtures of 2 solid substrates were conducted in semi-continuous mode. Experimental methane yields were always higher than the BMP values of mixtures calculated from the BMP of each substrate, highlighting the importance of endogenous production (methane produced from auto-degradation of microbial community and generated solids). The experimental methane productions under increasing OLRs corresponded well to the modeled data using the model with constant endogenous production and kinetics identified at 80% from total batch time. This model provides a simple and useful tool for technical design consultancies and plant operators to optimize the co-digestion and the choice of the OLRs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 50: From student to entry-level professional: Examining the role of language and written communications in the reacculturation of aerospace engineering students

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Keene, Michael L.; Kennedy, John M.; Hecht, Laura F.

    1995-01-01

    When students graduate and enter the world of work, they must make the transition from an academic to a professional knowledge community. Kenneth Bruffee's model of the social construction of knowledge suggests that language and written communication play a critical role in the reacculturation process that enables successful movement from one knowledge community to another. We present the results of a national (mail) survey that examined the technical communications abilities, skills, and competencies of 1,673 aerospace engineering students, who represent an academic knowledge community. These results are examined within the context of the technical communications behaviors and practices reported by 2,355 aerospace engineers and scientists employed in government and industry, who represent a professional knowledge community that the students expect to join. Bruffee's claim of the importance of language and written communication in the successful transition from an academic to a professional knowledge community is supported by the responses from the two communities we surveyed. Implications are offered for facilitating the reacculturation process of students to entry-level engineering professionals.

  1. Development of fault tolerant adaptive control laws for aerospace systems

    Science.gov (United States)

    Perez Rocha, Andres E.

    The main topic of this dissertation is the design, development and implementation of intelligent adaptive control techniques designed to maintain healthy performance of aerospace systems subjected to malfunctions, external parameter changes and/or unmodeled dynamics. The dissertation is focused on the development of novel adaptive control configurations that rely on non-linear functions that appear in the immune system of living organisms as main source of adaptation. One of the main goals of this dissertation is to demonstrate that these novel adaptive control architectures are able to improve overall performance and protect the system while reducing control effort and maintaining adequate operation outside bounds of nominal design. This research effort explores several phases, ranging from theoretical stability analysis, simulation and hardware implementation on different types of aerospace systems including spacecraft, aircraft and quadrotor vehicles. The results presented in this dissertation are focused on two main adaptivity approaches, the first one is intended for aerospace systems that do not attain large angles and use exact feedback linearization of Euler angle kinematics. A proof of stability is presented by means of the circle Criterion and Lyapunov's direct method. The second approach is intended for aerospace systems that can attain large attitude angles (e.g. space systems in gravity-less environments), the adaptation is incorporated on a baseline architecture that uses partial feedback linearization of quaternions kinematics. In this case, the closed loop stability was analyzed using Lyapunov's direct method and Barbalat's Lemma. It is expected that some results presented in this dissertation can contribute towards the validation and certification of direct adaptive controllers.

  2. Modelling of interactions between variable mass and density solid particles and swirling gas stream

    International Nuclear Information System (INIS)

    Wardach-Święcicka, I; Kardaś, D; Pozorski, J

    2011-01-01

    The aim of this work is to investigate the solid particles - gas interactions. For this purpose, numerical modelling was carried out by means of a commercial code for simulations of two-phase dispersed flows with the in-house models accounting for mass and density change of solid phase. In the studied case the particles are treated as spherical moving grains carried by a swirling stream of hot gases. Due to the heat and mass transfer between gas and solid phase, the particles are losing their mass and they are changing their volume. Numerical simulations were performed for turbulent regime, using two methods for turbulence modelling: RANS and LES.

  3. The Chameleon Solid Rocket Propulsion Model

    International Nuclear Information System (INIS)

    Robertson, Glen A.

    2010-01-01

    The Khoury and Weltman (2004a and 2004b) Chameleon Model presents an addition to the gravitation force and was shown by the author (Robertson, 2009a and 2009b) to present a new means by which one can view other forces in the Universe. The Chameleon Model is basically a density-dependent model and while the idea is not new, this model is novel in that densities in the Universe to include the vacuum of space are viewed as scalar fields. Such an analogy gives the Chameleon scalar field, dark energy/dark matter like characteristics; fitting well within cosmological expansion theories. In respect to this forum, in this paper, it is shown how the Chameleon Model can be used to derive the thrust of a solid rocket motor. This presents a first step toward the development of new propulsion models using density variations verse mass ejection as the mechanism for thrust. Further, through the Chameleon Model connection, these new propulsion models can be tied to dark energy/dark matter toward new space propulsion systems utilizing the vacuum scalar field in a way understandable by engineers, the key toward the development of such systems. This paper provides corrections to the Chameleon rocket model in Robertson (2009b).

  4. Advances in Computational Stability Analysis of Composite Aerospace Structures

    International Nuclear Information System (INIS)

    Degenhardt, R.; Araujo, F. C. de

    2010-01-01

    European aircraft industry demands for reduced development and operating costs. Structural weight reduction by exploitation of structural reserves in composite aerospace structures contributes to this aim, however, it requires accurate and experimentally validated stability analysis of real structures under realistic loading conditions. This paper presents different advances from the area of computational stability analysis of composite aerospace structures which contribute to that field. For stringer stiffened panels main results of the finished EU project COCOMAT are given. It investigated the exploitation of reserves in primary fibre composite fuselage structures through an accurate and reliable simulation of postbuckling and collapse. For unstiffened cylindrical composite shells a proposal for a new design method is presented.

  5. Perspectives on Advanced Learning Technologies and Learning Networks and Future Aerospace Workforce Environments

    Science.gov (United States)

    Noor, Ahmed K. (Compiler)

    2003-01-01

    An overview of the advanced learning technologies is given in this presentation along with a brief description of their impact on future aerospace workforce development. The presentation is divided into five parts (see Figure 1). In the first part, a brief historical account of the evolution of learning technologies is given. The second part describes the current learning activities. The third part describes some of the future aerospace systems, as examples of high-tech engineering systems, and lists their enabling technologies. The fourth part focuses on future aerospace research, learning and design environments. The fifth part lists the objectives of the workshop and some of the sources of information on learning technologies and learning networks.

  6. Modeling the electrified solid-liquid interface

    DEFF Research Database (Denmark)

    Rossmeisl, Jan; Skulason, Egill; Björketun, Mårten

    2008-01-01

    function can be related directly to the potential scale of the normal hydrogen electrode. We also show how finite-size effects in common periodic slab-type calculations can be avoided in calculations of activation energies and reaction energies for charge transfer reactions, where we use the Heyrovsky......A detailed atomistic model based on density functional theory calculations is presented of the charged solid-electrolyte interface. Having protons solvated in a water bilayer outside a Pt(111) slab with excess electrons, we show how the interface capacitance is well described and how the work...

  7. Numerical Modeling of Conjugate Heat Transfer in Fluid Network

    Science.gov (United States)

    Majumdar, Alok

    2004-01-01

    Fluid network modeling with conjugate heat transfer has many applications in Aerospace engineering. In modeling unsteady flow with heat transfer, it is important to know the variation of wall temperature in time and space to calculate heat transfer between solid to fluid. Since wall temperature is a function of flow, a coupled analysis of temperature of solid and fluid is necessary. In cryogenic applications, modeling of conjugate heat transfer is of great importance to correctly predict boil-off rate in propellant tanks and chill down of transfer lines. In TFAWS 2003, the present author delivered a paper to describe a general-purpose computer program, GFSSP (Generalized Fluid System Simulation Program). GFSSP calculates flow distribution in complex flow circuit for compressible/incompressible, with or without heat transfer or phase change in all real fluids or mixtures. The flow circuit constitutes of fluid nodes and branches. The mass, energy and specie conservation equations are solved at the nodes where as momentum conservation equations are solved at the branches. The proposed paper describes the extension of GFSSP to model conjugate heat transfer. The network also includes solid nodes and conductors in addition to fluid nodes and branches. The energy conservation equations for solid nodes solves to determine the temperatures of the solid nodes simultaneously with all conservation equations governing fluid flow. The numerical scheme accounts for conduction, convection and radiation heat transfer. The paper will also describe the applications of the code to predict chill down of cryogenic transfer line and boil-off rate of cryogenic propellant storage tank.

  8. Practical Education of Aerospace Field in Muroran Institute of Technology

    Science.gov (United States)

    Tanatsugu, Nobuhiro

    Engineering study in the field of aerospace is an effective way to enhance the student motivation. The young students can be attracted by the research and development aiming at returning its results to the public society. The Muroran Institute of Technology is carrying out the practical education in the field of real research and development by the Aerospace Research Center. The projects of the center is being performed well in cooperation with the national research organization and the private companies and thereby the students have the good opportunity to find the actual situation of the real world.

  9. Integrated Manufacturing of Aerospace Components by Superplastic Forming Technology

    Directory of Open Access Journals (Sweden)

    Ju Min Kyung

    2015-01-01

    Full Text Available Aerospace vehicle requires lightweight structures to obtain weight saving and fuel efficiency. It is known that superplastic characteristics of some materials provide significant opportunity for forming complicated, lightweight components of aerospace structure. One of the most important advantages of using superplastic forming process is its simplicity to form integral parts and economy in tooling[1]. For instance, it can be applied to blow-forming, in which a metal sheet is deformed due to the pressure difference of hydrostatic gas on both sides of the sheet. Since the loading medium is gas pressure difference, this forming is different from conventional sheet metal forming technique in that this is stress-controlled rather than strain and strain rate controlled. This method is especially advantageous when several sheet metals are formed into complex shapes. In this study, it is demonstrated that superplastic forming process with titanium and steel alloy can be applied to manufacturing lightweight integral structures of aerospace structural parts and rocket propulsion components. The result shows that the technology to design and develop the forming process of superplastic forming can be applied for near net shape forming of a complex contour of a thrust chamber and a toroidal fuel tank.

  10. Requirements for effective use of CFD in aerospace design

    Science.gov (United States)

    Raj, Pradeep

    1995-01-01

    This paper presents a perspective on the requirements that Computational Fluid Dynamics (CFD) technology must meet for its effective use in aerospace design. General observations are made on current aerospace design practices and deficiencies are noted that must be rectified for the U.S. aerospace industry to maintain its leadership position in the global marketplace. In order to rectify deficiencies, industry is transitioning to an integrated product and process development (IPPD) environment and design processes are undergoing radical changes. The role of CFD in producing data that design teams need to support flight vehicle development is briefly discussed. An overview of the current state of the art in CFD is given to provide an assessment of strengths and weaknesses of the variety of methods currently available, or under development, to produce aerodynamic data. Effectiveness requirements are examined from a customer/supplier view point with design team as customer and CFD practitioner as supplier. Partnership between the design team and CFD team is identified as an essential requirement for effective use of CFD. Rapid turnaround, reliable accuracy, and affordability are offered as three key requirements that CFD community must address if CFD is to play its rightful role in supporting the IPPD design environment needed to produce high quality yet affordable designs.

  11. Impedance Modeling of Solid Oxide Fuel Cell Cathodes

    DEFF Research Database (Denmark)

    Mortensen, Jakob Egeberg; Søgaard, Martin; Jacobsen, Torben

    2010-01-01

    A 1-dimensional impedance model for a solid oxide fuel cell cathode is formulated and applied to a cathode consisting of 50/50 wt% strontium doped lanthanum cobaltite and gadolinia doped ceria. A total of 42 impedance spectra were recorded in the temperature range: 555-852°C and in the oxygen...... partial pressure range 0.028-1.00 atm. The recorded impedance spectra were successfully analyzed using the developed impedance model in the investigated temperature and oxygen partial pressure range. It is also demonstrated that the model can be used to predict how impedance spectra evolve with different...

  12. Modeling and simulation of liquid diffusion through a porous finitely elastic solid

    KAUST Repository

    Zhao, Qiangsheng

    2013-01-29

    A new theory is proposed for the continuum modeling of liquid flow through a porous elastic solid. The solid and the voids are assumed to jointly constitute the macroscopic solid phase, while the liquid volume fraction is included as a separate state variable. A finite element implementation is employed to assess the predictive capacity of the proposed theory, with particular emphasis on the mechanical response of Nafion® membranes to the flow of water. © 2013 Springer-Verlag Berlin Heidelberg.

  13. Atomistic Modeling of the Fluid-Solid Interface in Simple Fluids

    Science.gov (United States)

    Hadjiconstantinou, Nicolas; Wang, Gerald

    2017-11-01

    Fluids can exhibit pronounced structuring effects near a solid boundary, typically manifested in a layered structure that has been extensively shown to directly affect transport across the interface. We present and discuss several results from molecular-mechanical modeling and molecular-dynamics (MD) simulations aimed at characterizing the structure of the first fluid layer directly adjacent to the solid. We identify a new dimensionless group - termed the Wall number - which characterizes the degree of fluid layering, by comparing the competing effects of wall-fluid interaction and thermal energy. We find that in the layering regime, several key features of the first layer layer - including its distance from the solid, its width, and its areal density - can be described using mean-field-energy arguments, as well as asymptotic analysis of the Nernst-Planck equation. For dense fluids, the areal density and the width of the first layer can be related to the bulk fluid density using a simple scaling relation. MD simulations show that these results are broadly applicable and robust to the presence of a second confining solid boundary, different choices of wall structure and thermalization, strengths of fluid-solid interaction, and wall geometries.

  14. Application verification research of cloud computing technology in the field of real time aerospace experiment

    Science.gov (United States)

    Wan, Junwei; Chen, Hongyan; Zhao, Jing

    2017-08-01

    According to the requirements of real-time, reliability and safety for aerospace experiment, the single center cloud computing technology application verification platform is constructed. At the IAAS level, the feasibility of the cloud computing technology be applied to the field of aerospace experiment is tested and verified. Based on the analysis of the test results, a preliminary conclusion is obtained: Cloud computing platform can be applied to the aerospace experiment computing intensive business. For I/O intensive business, it is recommended to use the traditional physical machine.

  15. Design and Fabrication of Aerospace-Grade Digital Composite Materials

    Data.gov (United States)

    National Aeronautics and Space Administration — This project aims to advance design rules and fabrication approaches to create aerospace-grade structures from digital composite materials. Digital materials are...

  16. Value-leverage by Aerospace Original Equipment Manufacturers

    NARCIS (Netherlands)

    Beelaerts van Blokland, W.W.A.

    2010-01-01

    With the creation of new aircraft products; Embraer E-170/190, Dassault 7X, Airbus A380 and Boeing B787, aerospace original equipment manufacturers (OEMs) involve suppliers not only with the co-production of aircraft sub systems, but also with the entire development of sub systems, like fuselage and

  17. Geometric modeling for computer aided design

    Science.gov (United States)

    Schwing, James L.; Olariu, Stephen

    1995-01-01

    The primary goal of this grant has been the design and implementation of software to be used in the conceptual design of aerospace vehicles particularly focused on the elements of geometric design, graphical user interfaces, and the interaction of the multitude of software typically used in this engineering environment. This has resulted in the development of several analysis packages and design studies. These include two major software systems currently used in the conceptual level design of aerospace vehicles. These tools are SMART, the Solid Modeling Aerospace Research Tool, and EASIE, the Environment for Software Integration and Execution. Additional software tools were designed and implemented to address the needs of the engineer working in the conceptual design environment. SMART provides conceptual designers with a rapid prototyping capability and several engineering analysis capabilities. In addition, SMART has a carefully engineered user interface that makes it easy to learn and use. Finally, a number of specialty characteristics have been built into SMART which allow it to be used efficiently as a front end geometry processor for other analysis packages. EASIE provides a set of interactive utilities that simplify the task of building and executing computer aided design systems consisting of diverse, stand-alone, analysis codes. Resulting in a streamlining of the exchange of data between programs reducing errors and improving the efficiency. EASIE provides both a methodology and a collection of software tools to ease the task of coordinating engineering design and analysis codes.

  18. A Variational Model for Two-Phase Immiscible Electroosmotic Flow at Solid Surfaces

    KAUST Repository

    Shao, Sihong

    2012-01-01

    We develop a continuum hydrodynamic model for two-phase immiscible flows that involve electroosmotic effect in an electrolyte and moving contact line at solid surfaces. The model is derived through a variational approach based on the Onsager principle of minimum energy dissipation. This approach was first presented in the derivation of a continuum hydrodynamic model for moving contact line in neutral two-phase immiscible flows (Qian, Wang, and Sheng, J. Fluid Mech. 564, 333-360 (2006)). Physically, the electroosmotic effect can be formulated by the Onsager principle as well in the linear response regime. Therefore, the same variational approach is applied here to the derivation of the continuum hydrodynamic model for charged two-phase immiscible flows where one fluid component is an electrolyte exhibiting electroosmotic effect on a charged surface. A phase field is employed to model the diffuse interface between two immiscible fluid components, one being the electrolyte and the other a nonconductive fluid, both allowed to slip at solid surfaces. Our model consists of the incompressible Navier-Stokes equation for momentum transport, the Nernst-Planck equation for ion transport, the Cahn-Hilliard phase-field equation for interface motion, and the Poisson equation for electric potential, along with all the necessary boundary conditions. In particular, all the dynamic boundary conditions at solid surfaces, including the generalized Navier boundary condition for slip, are derived together with the equations of motion in the bulk region. Numerical examples in two-dimensional space, which involve overlapped electric double layer fields, have been presented to demonstrate the validity and applicability of the model, and a few salient features of the two-phase immiscible electroosmotic flows at solid surface. The wall slip in the vicinity of moving contact line and the Smoluchowski slip in the electric double layer are both investigated. © 2012 Global-Science Press.

  19. A novel approach to model the transient behavior of solid-oxide fuel cell stacks

    Science.gov (United States)

    Menon, Vikram; Janardhanan, Vinod M.; Tischer, Steffen; Deutschmann, Olaf

    2012-09-01

    This paper presents a novel approach to model the transient behavior of solid-oxide fuel cell (SOFC) stacks in two and three dimensions. A hierarchical model is developed by decoupling the temperature of the solid phase from the fluid phase. The solution of the temperature field is considered as an elliptic problem, while each channel within the stack is modeled as a marching problem. This paper presents the numerical model and cluster algorithm for coupling between the solid phase and fluid phase. For demonstration purposes, results are presented for a stack operated on pre-reformed hydrocarbon fuel. Transient response to load changes is studied by introducing step changes in cell potential and current. Furthermore, the effect of boundary conditions and stack materials on response time and internal temperature distribution is investigated.

  20. A stochastic model of solid state thin film deposition: Application to chalcopyrite growth

    Directory of Open Access Journals (Sweden)

    Robert J. Lovelett

    2016-04-01

    Full Text Available Developing high fidelity quantitative models of solid state reaction systems can be challenging, especially in deposition systems where, in addition to the multiple competing processes occurring simultaneously, the solid interacts with its atmosphere. In this work, we develop a model for the growth of a thin solid film where species from the atmosphere adsorb, diffuse, and react with the film. The model is mesoscale and describes an entire film with thickness on the order of microns. Because it is stochastic, the model allows us to examine inhomogeneities and agglomerations that would be impossible to characterize with deterministic methods. We demonstrate the modeling approach with the example of chalcopyrite Cu(InGa(SeS2 thin film growth via precursor reaction, which is a common industrial method for fabricating thin film photovoltaic modules. The model is used to understand how and why through-film variation in the composition of Cu(InGa(SeS2 thin films arises and persists. We believe that the model will be valuable as an effective quantitative description of many other materials systems used in semiconductors, energy storage, and other fast-growing industries.

  1. NASA-UVA Light Aerospace Alloy and Structures Technology Program (LA2ST)

    Science.gov (United States)

    Gangloff, Richard P.; Scully, John R.; Stoner, Glenn E.; Thornton, Earl A.; Wawner, Franklin E., Jr.; Wert, John A.

    1993-01-01

    The NASA-UVA Light Aerospace Alloy and Structures Technology (LA2ST) Program continues a high level of activity. Progress achieved between 1 Jan. and 30 Jun. 1993 is reported. The objective of the LA2ST Program is to conduct interdisciplinary graduate student research on the performance of next generation, light weight aerospace alloys, composites, and thermal gradient structures in collaboration with NASA-Langley researchers. The following projects are addressed: environmental fatigue of Al-Li-Cu alloys; mechanisms of localized corrosion and environmental fracture in Al-Cu-Li-Mg-Ag alloy X2095 and compositional variations; the effect of zinc additions on the precipitation and stress corrosion cracking behavior of alloy 8090; hydrogen interactions with Al-Li-Cu alloy 2090 and model alloys; metastable pitting of aluminum alloys; cryogenic fracture toughness of Al-Cu-Li + In alloys; the fracture toughness of Weldalite (TM); elevated temperature cracking of advanced I/M aluminum alloys; response of Ti-1100/SCS-6 composites to thermal exposure; superplastic forming of Weldalite (TM); research to incorporate environmental effects into fracture mechanics fatigue life prediction codes such as NASA FLAGRO; and thermoviscoplastic behavior.

  2. BIOLEACH: Coupled modeling of leachate and biogas production on solid waste landfills

    Science.gov (United States)

    Rodrigo-Clavero, Maria-Elena; Rodrigo-Ilarri, Javier

    2015-04-01

    One of the most important factors to address when performing the environmental impact assessment of urban solid waste landfills is to evaluate the leachate production. Leachate management (collection and treatment) is also one of the most relevant economical aspects to take into account during the landfill life. Leachate is formed as a solution of biological and chemical components during operational and post-operational phases on urban solid waste landfills as a combination of different processes that involve water gains and looses inside the solid waste mass. Infiltration of external water coming from precipitation is the most important component on this water balance. However, anaerobic waste decomposition and biogas formation processes play also a role on the balance as water-consuming processes. The production of leachate one biogas is therefore a coupled process. Biogas production models usually consider optimal conditions of water content on the solid waste mass. However, real conditions during the operational phase of the landfill may greatly differ from these optimal conditions. In this work, the first results obtained to predict both the leachate and the biogas production as a single coupled phenomenon on real solid waste landfills are shown. The model is applied on a synthetic case considering typical climatological conditions of Mediterranean catchments.

  3. An integration scheme for stiff solid-gas reactor models

    Directory of Open Access Journals (Sweden)

    Bjarne A. Foss

    2001-04-01

    Full Text Available Many dynamic models encounter numerical integration problems because of a large span in the dynamic modes. In this paper we develop a numerical integration scheme for systems that include a gas phase, and solid and liquid phases, such as a gas-solid reactor. The method is based on neglecting fast dynamic modes and exploiting the structure of the algebraic equations. The integration method is suitable for a large class of industrially relevant systems. The methodology has proven remarkably efficient. It has in practice performed excellent and been a key factor for the success of the industrial simulator for electrochemical furnaces for ferro-alloy production.

  4. A Model of Solid Waste Management Based Multilateral Co-Operation in Semi-Urban Community

    Science.gov (United States)

    Kanchanabhandhu, Chanchai; Woraphong, Seree

    2016-01-01

    The purpose of this research was to construct a model of solid waste management based on multilateral cooperation in semi-urban community. Its specific objectives were to 1) study the solid waste situation and involvement of community in the solid waste management in Wangtaku Sub-district, Muang District, Nakhon Pathom Province; 2) construct a…

  5. Characterization of 2024-T3: An aerospace aluminum alloy

    International Nuclear Information System (INIS)

    Huda, Zainul; Taib, Nur Iskandar; Zaharinie, Tuan

    2009-01-01

    The 2024-T3 aerospace aluminum alloy, reported in this investigation, was acquired from a local aerospace industry: Royal Malaysian Air Force (RMAF). The heat treatable 2024-T3 aluminum alloy has been characterized by use of modern metallographic and material characterization techniques (e.g. EPMA, SEM). The microstructural characterization of the metallographic specimen involved use of an optical microscope linked with a computerized imaging system using MSQ software. The use of EPMA and electron microprobe elemental maps enabled us to detect three types of inclusions: Al-Cu, Al-Cu-Fe-Mn, and Al-Cu-Fe-Si-Mn enriched regions. In particular, the presence of Al 2 CuMg (S-phase) and the CuAl 2 (θ') phases indicated precipitation strengthening in the aluminum alloy

  6. Mathematical modeling in municipal solid waste management: case study of Tehran.

    Science.gov (United States)

    Akbarpour Shirazi, Mohsen; Samieifard, Reza; Abduli, Mohammad Ali; Omidvar, Babak

    2016-01-01

    Solid Waste Management (SWM) in metropolises with systematic methods and following environmental issues, is one of the most important subjects in the area of urban management. In this regard, it is regarded as a legal entity so that its activities are not overshadowed by other urban activities. In this paper, a linear mathematical programming model has been designed for integrated SWM. Using Lingo software and required data from Tehran, the proposed model has been applied for Tehran SWM system as a case study. To determine the optimal status of the available system for Tehran's Solid Waste Management System (SWMS), a novel linear programming model is applied. Tehran has 22 municipal regions with 11 transfer stations and 10 processing units. By running of the model, the transfer stations and processing units are decreased to 10 and 6 units, respectively. The proposed model is an alternative method for improvement the SWMS by decreasing the transfer stations and processing units.

  7. Aerospace Engineering Systems and the Advanced Design Technologies Testbed Experience

    Science.gov (United States)

    VanDalsem, William R.; Livingston, Mary E.; Melton, John E.; Torres, Francisco J.; Stremel, Paul M.

    1999-01-01

    Continuous improvement of aerospace product development processes is a driving requirement across much of the aerospace community. As up to 90% of the cost of an aerospace product is committed during the first 10% of the development cycle, there is a strong emphasis on capturing, creating, and communicating better information (both requirements and performance) early in the product development process. The community has responded by pursuing the development of computer-based systems designed to enhance the decision-making capabilities of product development individuals and teams. Recently, the historical foci on sharing the geometrical representation and on configuration management are being augmented: 1) Physics-based analysis tools for filling the design space database; 2) Distributed computational resources to reduce response time and cost; 3) Web-based technologies to relieve machine-dependence; and 4) Artificial intelligence technologies to accelerate processes and reduce process variability. The Advanced Design Technologies Testbed (ADTT) activity at NASA Ames Research Center was initiated to study the strengths and weaknesses of the technologies supporting each of these trends, as well as the overall impact of the combination of these trends on a product development event. Lessons learned and recommendations for future activities are reported.

  8. 3DXRD characterization and modeling of solid-state transformation processes

    DEFF Research Database (Denmark)

    Juul Jensen, Dorte; Offerman, S.E.; Sietsma, J.

    2008-01-01

    of metallic microstructures with much more detail than hitherto possible. Among these modeling activities are three-dimensional (3D) geometric modeling, 3D molecular dynamics modeling, 3D phase-field modeling, two-dimensional (2D) cellular automata, and 2D Monte Carlo simulations....... data valuable for validation of various models of microstructural evolution is discussed, Examples of 3DXRD measurements related to recrystallization and to solid-state phase transformations in metals are described. 3DXRD measurements have led to new modeling activity predicting the evolution...

  9. Analytical model for the effects of wetting on thermal boundary conductance across solid/classical liquid interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Caplan, Matthew E.; Giri, Ashutosh; Hopkins, Patrick E., E-mail: phopkins@virginia.edu [Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States)

    2014-04-21

    We develop an analytical model for the thermal boundary conductance between a solid and a liquid. By infusing recent developments in the phonon theory of liquid thermodynamics with diffuse mismatch theory, we derive a closed form model that can predict the effects of wetting on the thermal boundary conductance across an interface between a solid and a classical liquid. We account for the complete wetting (hydrophilicity), or lack thereof (hydrophobicity), of the liquid to the solid by considering varying contributions of transverse mode interactions between the solid and liquid interfacial layers; this transverse coupling relationship is determined with local density of states calculations from molecular dynamics simulations between Lennard-Jones solids and a liquids with different interfacial interaction energies. We present example calculations for the thermal boundary conductance between both hydrophobic and hydrophilic interfaces of Al/water and Au/water, which show excellent agreement with measured values reported by Ge et al. [Z. Ge, D. G. Cahill, and P. V. Braun, Phys. Rev. Lett. 96, 186101 (2006)]. Our model does not require any fitting parameters and is appropriate to model heat flow across any planar interface between a solid and a classical liquid.

  10. Representing the Past by Solid Modeling + Golden Ratio Analysis

    Science.gov (United States)

    Ding, Suining

    2008-01-01

    This paper describes the procedures of reconstructing ancient architecture using solid modeling with geometric analysis, especially the Golden Ratio analysis. In the past the recovery and reconstruction of ruins required bringing together fragments of evidence and vast amount of measurements from archaeological site. Although researchers and…

  11. A mathematical model of the solid-polymer-electrolyte fuel cell

    International Nuclear Information System (INIS)

    Bernardi, D.M.; Verbrugge, M.W.

    1992-01-01

    This paper presents a mathematical model of the solid-polymer-electrolyte fuel cell and apply it to (i) investigate factors that limit cell performance and (ii) elucidate the mechanism of species transport in the complex network of gas, liquid, and solid phases of the cell. Calculations of cell polarization behavior compare favorably with existing experimental data. For most practical electrode thicknesses, model results indicate that the volume fraction of the cathode available for gas transport must exceed 20% in order to avoid unacceptably low cell-limiting current densities. It is shown that membrane dehydration can also pose limitations on operating current density; circumvention of this problem by appropriate membrane and electrode design and efficient water-management schemes is discussed. The authors' model results indicate that for a broad range of practical current densities there are no external water requirements because the water produced at the cathode is enough to satisfy the water requirement of the membrane

  12. Modeling of positron states and annihilation in solids

    International Nuclear Information System (INIS)

    Puska, M.J.

    2003-01-01

    Theoretical models and computational aspects to describe positron states and to predict positron annihilation characteristics in solids are discussed. The comparison of the calculated positron lifetimes, core annihilation lineshapes, and two-dimensional angular correlation maps with experimental results are used in identifying the structure (including the chemical composition) of vacancy-type defects and their development e.g. during thermal annealing. The basis of the modeling is the two-component density-functional theory. The ensuing approximations and the state-of-the-art electronic-structure computation methods enable practical schemes with a quantitative predicting power. (author)

  13. Airborne aerospace; interview with business development manager space

    NARCIS (Netherlands)

    Woldendorp, S.; Nevinskala, A.; Gupta, S.

    2013-01-01

    Airborne Composites designs and manufactures composite parts for the Aerospace, Oil & Gas, Marine and other industries since 1995. They are involved in notable hightech projects, from the Galileo Satellites, to the Gulfstream aircraft for Fokker and the ALMA astronomical telescope. The Leonardo

  14. Research on non-destructive testing (NDT) aerospace igniter fuse with neutron radiography (NR)

    International Nuclear Information System (INIS)

    Mo Dawei; Liu Yisi; Cai Qingsheng; Chen Boxian

    1995-01-01

    The research works, facilities and results of NDT aerospace igniter fuse with neutron radiography at Tsinghua University swimming-pool reactor are introduced. The image quality (NR) of ASTM E545-85 I level was approached. The NR experimental research of the typical and possible defects was performed. The theoretical analysis was performed too. The feasibility of NDT aerospace igniter fuse with NR was proved experimentally

  15. Real-Time Impact Visualization Inspection of Aerospace Composite Structures with Distributed Sensors.

    Science.gov (United States)

    Si, Liang; Baier, Horst

    2015-07-08

    For the future design of smart aerospace structures, the development and application of a reliable, real-time and automatic monitoring and diagnostic technique is essential. Thus, with distributed sensor networks, a real-time automatic structural health monitoring (SHM) technique is designed and investigated to monitor and predict the locations and force magnitudes of unforeseen foreign impacts on composite structures and to estimate in real time mode the structural state when impacts occur. The proposed smart impact visualization inspection (IVI) technique mainly consists of five functional modules, which are the signal data preprocessing (SDP), the forward model generator (FMG), the impact positioning calculator (IPC), the inverse model operator (IMO) and structural state estimator (SSE). With regard to the verification of the practicality of the proposed IVI technique, various structure configurations are considered, which are a normal CFRP panel and another CFRP panel with "orange peel" surfaces and a cutout hole. Additionally, since robustness against several background disturbances is also an essential criterion for practical engineering demands, investigations and experimental tests are carried out under random vibration interfering noise (RVIN) conditions. The accuracy of the predictions for unknown impact events on composite structures using the IVI technique is validated under various structure configurations and under changing environmental conditions. The evaluated errors all fall well within a satisfactory limit range. Furthermore, it is concluded that the IVI technique is applicable for impact monitoring, diagnosis and assessment of aerospace composite structures in complex practical engineering environments.

  16. Modeling and Analysis of a Three-Phase Solid-State Var ...

    African Journals Online (AJOL)

    Modeling and Analysis of a Three-Phase Solid-State Var Compensator (SSVC) ... Nigerian Journal of Technology. Journal Home ... The problems associated with the flow of reactive power in transmission and distribution lines are well known.

  17. Role of different types of solid models in hydrodynamic modeling and their effects on groundwater protection processes

    Science.gov (United States)

    Bódi, Erika; Buday, Tamás; McIntosh, Richard William

    2013-04-01

    Defining extraction-modified flow patterns with hydrodynamic models is a pivotal question in preserving groundwater resources regarding both quality and quantity. Modeling is the first step in groundwater protection the main result of which is the determination of the protective area depending on the amount of extracted water. Solid models have significant effects on hydrodynamic models as they are based on the solid models. Due to the legislative regulations, on protection areas certain restrictions must be applied which has firm consequences on economic activities. In Hungarian regulations there are no clear instructions for the establishment of either geological or hydrodynamic modeling, however, modeling itself is an obligation. Choosing the modeling method is a key consideration for further numerical calculations and it is decisive regarding the shape and size of the groundwater protection area. The geometry of hydrodynamic model layers is derived from the solid model. There are different geological approaches including lithological and sequence stratigraphic classifications furthermore in the case of regional models, formation-based hydrostratigraphic units are also applicable. Lithological classification is based on assigning and mapping of lithotypes. When the geometry (e.g. tectonic characteristics) of the research area is not known, horizontal bedding is assumed the probability of which can not be assessed based on only lithology. If the geological correlation is based on sequence stratigraphic studies, the cyclicity of sediment deposition is also considered. This method is more integrated thus numerous parameters (e.g. electrofacies) are taken into consideration studying the geological conditions ensuring more reliable modeling. Layers of sequence stratigraphic models can be either lithologically homogeneous or they may include greater cycles of sediments containing therefore several lithological units. The advantage of this is that the modeling can

  18. Aerospace reliability applied to biomedicine.

    Science.gov (United States)

    Lalli, V. R.; Vargo, D. J.

    1972-01-01

    An analysis is presented that indicates that the reliability and quality assurance methodology selected by NASA to minimize failures in aerospace equipment can be applied directly to biomedical devices to improve hospital equipment reliability. The Space Electric Rocket Test project is used as an example of NASA application of reliability and quality assurance (R&QA) methods. By analogy a comparison is made to show how these same methods can be used in the development of transducers, instrumentation, and complex systems for use in medicine.

  19. Proposal for a EU quality label for aerospace education

    Directory of Open Access Journals (Sweden)

    Franco BERNELLI-ZAZZERA

    2018-06-01

    Full Text Available The paper presents a possible roadmap for the definition of a European quality label for aerospace related higher education degrees. The proposal is the result of a two-years long Horizon 2020 project that has involved a great portion of the European stakeholders in aerospace: Universities, research centres, industries (both small and large networks, associations and accreditation agencies. The core concept established is that it is possible to establish a sector-specific, content based, quality system, that can complement the existing national or European accreditation systems, providing added value to the internal and/or external quality assurance processes that are in place in most EU countries. The tools and processes proposed are sufficiently simple to be manageable by Universities in addition to their national accreditation processes or as stand-alone assessment. The main goal of the proposed process is the evaluation of the quality of the aerospace curricula in the European context, whereas the accreditation of the programme can be seen as an optional extension of the process, subject to further national regulations. The process is proposed in view of the awarding of a sector-specific, content based, quality label, to be issued by an appropriate legally recognized and qualified institution. 8 field tests with volunteering universities throughout Europe have been performed. They experienced the method as very practical and to the point.

  20. Hybrid planar lightwave circuits for defense and aerospace applications

    Science.gov (United States)

    Zhang, Hua; Bidnyk, Serge; Yang, Shiquan; Balakrishnan, Ashok; Pearson, Matt; O'Keefe, Sean

    2010-04-01

    We present innovations in Planar Lightwave Circuits (PLCs) that make them ideally suited for use in advanced defense and aerospace applications. We discuss PLCs that contain no micro-optic components, no moving parts, pose no spark or fire hazard, are extremely small and lightweight, and are capable of transporting and processing a range of optical signals with exceptionally high performance. This PLC platform is designed for on-chip integration of active components such as lasers and detectors, along with transimpedance amplifiers and other electronics. These active components are hybridly integrated with our silica-on-silicon PLCs using fully-automated robotics and image recognition technology. This PLC approach has been successfully applied to the design and fabrication of multi-channel transceivers for aerospace applications. The chips contain hybrid DFB lasers and high-efficiency detectors, each capable of running over 10 Gb/s, with mixed digital and analog traffic multiplexed to a single optical fiber. This highlyintegrated functionality is combined onto a silicon chip smaller than 4 x 10 mm, weighing failures after extreme temperature cycling through a range of > 125 degC, and more than 2,000 hours operating at 95 degC ambient air temperature. We believe that these recent advancements in planar lightwave circuits are poised to revolutionize optical communications and interconnects in the aerospace and defense industries.

  1. Big Data in the Aerospace Industry

    Directory of Open Access Journals (Sweden)

    Victor Emmanuell BADEA

    2018-01-01

    Full Text Available This paper presents the approaches related to the need for large volume data analysis, Big Data, and also the information that the beneficiaries of this analysis can interpret. Aerospace companies understand better the challenges of Big Data than the rest of the industries. Also, in this paper we describe a novel analytical system that enables query processing and predictive analytics over streams of large aviation data.

  2. Pathways and Challenges to Innovation in Aerospace

    Science.gov (United States)

    Terrile, Richard J.

    2010-01-01

    This paper explores impediments to innovation in aerospace and suggests how successful pathways from other industries can be adopted to facilitate greater innovation. Because of its nature, space exploration would seem to be a ripe field of technical innovation. However, engineering can also be a frustratingly conservative endeavor when the realities of cost and risk are included. Impediments like the "find the fault" engineering culture, the treatment of technical risk as almost always evaluated in terms of negative impact, the difficult to account for expansive Moore's Law growth when making predictions, and the stove-piped structural organization of most large aerospace companies and federally funded research laboratories tend to inhibit cross-cutting technical innovation. One successful example of a multi-use cross cutting application that can scale with Moore's Law is the Evolutionary Computational Methods (ECM) technique developed at the Jet Propulsion Lab for automated spectral retrieval. Future innovations like computational engineering and automated design optimization can potentially redefine space exploration, but will require learning lessons from successful innovators.

  3. A computer model for dispersed fluid-solid turbulent flows

    International Nuclear Information System (INIS)

    Liu, C.H.; Tulig, T.J.

    1985-01-01

    A computer model is being developed to simulate two-phase turbulent flow phenomena in fluids containing finely dispersed solids. The model is based on a dual-continuum picture of the individual phases and an extension of a two-equation turbulence closure theory. The resulting set of nonlinear partial differential equations are solved using a finite difference procedure with special treatment to promote convergence. The model has been checked against a number of idealized flow problems with known solutions. The authors are currently comparing model predictions with measurements to determine a proper set of turbulence parameters needed for simulating two-phase turbulent flows

  4. Resource Management and Contingencies in Aerospace Concurrent Engineering

    Science.gov (United States)

    Karpati, Gabe; Hyde, Tupper; Peabody, Hume; Garrison, Matthew

    2012-01-01

    significant concern in designing complex systems implementing new technologies is that while knowledge about the system is acquired incrementally, substantial financial commitments, even make-or-break decisions, must be made upfront, essentially in the unknown. One practice that helps in dealing with this dichotomy is the smart embedding of contingencies and margins in the design to serve as buffers against surprises. This issue presents itself in full force in the aerospace industry, where unprecedented systems are formulated and committed to as a matter of routine. As more and more aerospace mission concepts are generated by concurrent design laboratories, it is imperative that such laboratories apply well thought-out contingency and margin structures to their designs. The first part of this publication provides an overview of resource management techniques and standards used in the aerospace industry. That is followed by a thought provoking treatise on margin policies. The expose presents the actual flight telemetry data recorded by the thermal discipline during several recent NASA Goddard Space Flight Center missions. The margins actually achieved in flight are compared against pre-flight predictions, and the appropriateness and the ramifications of having designed with rigid margins to bounding stacked worst case conditions are assessed. The second half of the paper examines the particular issues associated with the application of contingencies and margins in the concurrent engineering environment. In closure, a discipline-by-discipline disclosure of the contingency and margin policies in use at the Integrated Design Center at NASA s Goddard Space Flight Center is made.

  5. The Effect of Online Systems Analysis Training on Aerospace Industry Business Performance: A Qualitative Study

    Science.gov (United States)

    Burk, Erlan

    2012-01-01

    Aerospace companies needed additional research on technology-based training to verify expectations when enhancing human capital through online systems analysis training. The research for online systems analysis training provided aerospace companies a means to verify expectations for systems analysis technology-based training on business…

  6. Recoil chemistry and solid state exchange in cobalt complexes : a new model

    International Nuclear Information System (INIS)

    Ramshesh, V.

    1981-01-01

    During the last thirty years considerable work has been done on various aspects of recoil chemistry and solid state exchange in cobalt complexes. Several interesting features such as 'oxygen effect', 'water of hydration effect', 'dilution with isomorphous materials', etc., have been observed. These data led workers to reject the older hypothesis based on 'fragmentation' and 'recombination' and suggest models based on exciton or electron induced exchange. However some recent data show that perhaps both the processes viz., thermal annealing in n-irradiated systems and solid state exchange are not bulk processes. This has led the author to propose a new model. In this model greater emphasis is placed on dissociation reactions followed by recombination and/or exchange reactions. (author)

  7. Solid rocket motor cost model

    Science.gov (United States)

    Harney, A. G.; Raphael, L.; Warren, S.; Yakura, J. K.

    1972-01-01

    A systematic and standardized procedure for estimating life cycle costs of solid rocket motor booster configurations. The model consists of clearly defined cost categories and appropriate cost equations in which cost is related to program and hardware parameters. Cost estimating relationships are generally based on analogous experience. In this model the experience drawn on is from estimates prepared by the study contractors. Contractors' estimates are derived by means of engineering estimates for some predetermined level of detail of the SRM hardware and program functions of the system life cycle. This method is frequently referred to as bottom-up. A parametric cost analysis is a useful technique when rapid estimates are required. This is particularly true during the planning stages of a system when hardware designs and program definition are conceptual and constantly changing as the selection process, which includes cost comparisons or trade-offs, is performed. The use of cost estimating relationships also facilitates the performance of cost sensitivity studies in which relative and comparable cost comparisons are significant.

  8. Advanced impedance modeling of solid oxide electrochemical cells

    DEFF Research Database (Denmark)

    Graves, Christopher R.; Hjelm, Johan

    2014-01-01

    Impedance spectroscopy is a powerful technique for detailed study of the electrochemical and transport processes that take place in fuel cells and electrolysis cells, including solid oxide cells (SOCs). Meaningful analysis of impedance measurements is nontrivial, however, because a large number...... techniques to provide good guesses for the modeling parameters, like transforming the impedance data to the distribution of relaxation times (DRT), together with experimental parameter sensitivity studies, is the state-of-the-art approach to achieve good EC model fits. Here we present new impedance modeling...... electrode and 2-D gas transport models which have fewer unknown parameters for the same number of processes, (ii) use of a new model fitting algorithm, “multi-fitting”, in which multiple impedance spectra are fit simultaneously with parameters linked based on the variation of measurement conditions, (iii...

  9. The elastic solid solution model for minerals at high pressures and temperatures

    Science.gov (United States)

    Myhill, R.

    2018-02-01

    Non-ideality in mineral solid solutions affects their elastic and thermodynamic properties, their thermobaric stability, and the equilibrium phase relations in multiphase assemblages. At a given composition and state of order, non-ideality in minerals is typically modelled via excesses in Gibbs free energy which are either constant or linear with respect to pressure and temperature. This approach has been extremely successful when modelling near-ideal solutions. However, when the lattice parameters of the solution endmembers differ significantly, extrapolations of thermodynamic properties to high pressures using these models may result in significant errors. In this paper, I investigate the effect of parameterising solution models in terms of the Helmholtz free energy, treating volume (or lattice parameters) rather than pressure as an independent variable. This approach has been previously applied to models of order-disorder, but the implications for the thermodynamics and elasticity of solid solutions have not been fully explored. Solid solution models based on the Helmholtz free energy are intuitive at a microscopic level, as they automatically include the energetic contribution from elastic deformation of the endmember lattices. A chemical contribution must also be included in such models, which arises from atomic exchange within the solution. Derivations are provided for the thermodynamic properties of n-endmember solutions. Examples of the use of the elastic model are presented for the alkali halides, pyroxene, garnet, and bridgmanite solid solutions. Elastic theory provides insights into the microscopic origins of non-ideality in a range of solutions, and can make accurate predictions of excess enthalpies, entropies, and volumes as a function of volume and temperature. In solutions where experimental data are sparse or contradictory, the Helmholtz free energy approach can be used to assess the magnitude of excess properties and their variation as a function

  10. Deuteron NMR and modelling in solid polymers

    International Nuclear Information System (INIS)

    Hirschinger, J.

    1992-01-01

    Deuteron NMR techniques are described and some recent applications to the study of rotational motions in solid polymers are reviewed. The information content and the domain of applicability of each technique are presented. Ultra-slow motions are studied in real time without any motional model consideration. For very fast motions, computer molecular dynamics simulations are shown to complement the NMR results. Experimental examples deal with the chain motion in the crystalline α-phase of poly(vinylidenefluoride) and nylon 6,6

  11. 7th International symposium on NDT in aerospace 2015

    International Nuclear Information System (INIS)

    2015-01-01

    Non-Destructive Testing and Evaluation is one of the major requirements in aerospace structural design. Hardly any of the components manufactured is not allowed to pass quality assurance without having gone through any of the various NDT procedures being around. For damage tolerant design as used in aviation NDT is a prerequisite. Appropriate use of NDT guarantees safety in aerospace and is thus a subject of highest attention. Major topics to be discussed among others at this event will include the physics of NDT, sensors and material interaction, design of complete inspection systems and data evaluation such as for automated image processing. A special focus will also be towards improvement in inspection speed and transfer of laboratory NDT into production and manufacturing process integrated testing for in-line inspection.

  12. Characterization of 2024-T3: An aerospace aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Huda, Zainul [Department of Mechanical Engineering, University of Malaya, Kuala Lumpur (Malaysia)], E-mail: drzainulhuda@hotmail.com; Taib, Nur Iskandar [Department of Geology, University of Malaya, Kuala Lumpur (Malaysia)], E-mail: ntaib@alumni.indiana.edu; Zaharinie, Tuan [Department of Mechanical Engineering, University of Malaya, Kuala Lumpur (Malaysia)], E-mail: rinie_3483@hotmail.com

    2009-02-15

    The 2024-T3 aerospace aluminum alloy, reported in this investigation, was acquired from a local aerospace industry: Royal Malaysian Air Force (RMAF). The heat treatable 2024-T3 aluminum alloy has been characterized by use of modern metallographic and material characterization techniques (e.g. EPMA, SEM). The microstructural characterization of the metallographic specimen involved use of an optical microscope linked with a computerized imaging system using MSQ software. The use of EPMA and electron microprobe elemental maps enabled us to detect three types of inclusions: Al-Cu, Al-Cu-Fe-Mn, and Al-Cu-Fe-Si-Mn enriched regions. In particular, the presence of Al{sub 2}CuMg (S-phase) and the CuAl{sub 2} ({theta}') phases indicated precipitation strengthening in the aluminum alloy.

  13. Measurement of baseline and orientation between distributed aerospace platforms.

    Science.gov (United States)

    Wang, Wen-Qin

    2013-01-01

    Distributed platforms play an important role in aerospace remote sensing, radar navigation, and wireless communication applications. However, besides the requirement of high accurate time and frequency synchronization for coherent signal processing, the baseline between the transmitting platform and receiving platform and the orientation of platform towards each other during data recording must be measured in real time. In this paper, we propose an improved pulsed duplex microwave ranging approach, which allows determining the spatial baseline and orientation between distributed aerospace platforms by the proposed high-precision time-interval estimation method. This approach is novel in the sense that it cancels the effect of oscillator frequency synchronization errors due to separate oscillators that are used in the platforms. Several performance specifications are also discussed. The effectiveness of the approach is verified by simulation results.

  14. NASA Engineering Safety Center NASA Aerospace Flight Battery Systems Working Group 2007 Proactive Task Status

    Science.gov (United States)

    Manzo, Michelle A.

    2007-01-01

    In 2007, the NASA Engineering Safety Center (NESC) chartered the NASA Aerospace Flight Battery Systems Working Group to bring forth and address critical battery-related performance/manufacturing issues for NASA and the aerospace community. A suite of tasks identifying and addressing issues related to Ni-H2 and Li-ion battery chemistries was submitted and selected for implementation. The current NESC funded are: (1) Wet Life of Ni-H2 Batteries (2) Binding Procurement (3) NASA Lithium-Ion Battery Guidelines (3a) Li-Ion Performance Assessment (3b) Li-Ion Guidelines Document (3b-i) Assessment of Applicability of Pouch Cells for Aerospace Missions (3b-ii) High Voltage Risk Assessment (3b-iii) Safe Charge Rates for Li-Ion Cells (4) Availability of Source Material for Li-Ion Cells (5) NASA Aerospace Battery Workshop This presentation provides a brief overview of the tasks in the 2007 plan and serves as an introduction to more detailed discussions on each of the specific tasks.

  15. Bed models for solid fuel conversion process in grate-fired boilers

    DEFF Research Database (Denmark)

    Costa, M.; Massarotti, N.; Indrizzi, V.

    2013-01-01

    -chemical processes are divided in two successive sections: drying and conversion (which includes pyrolysis, gasification and combustion). The second model is an empirical 1D approach. The two models need input data such as composition, temperature and feeding rate of biomass and primary air. Temperature, species...... to describe the thermo-chemical conversion process of a solid fuel bed in a grate-fired boiler is presented. In this work both models consider the incoming solid fuel as subjected to drying, pyrolysis, gasification and combustion. In the first approach the biomass bed is treated as a 0D system, but the thermo...... concentrations and velocity of the producer gas leaving the fuel bed provided by the two models are compared. A sensitivity analysis with respect to mass flow rate of the primary air is also performed, as well as a further comparison regarding the dependence of the producer gas properties on the initial moisture...

  16. Cognitive engineering in aerospace applications

    Science.gov (United States)

    Woods, David D.

    1993-01-01

    The progress that was made with respect to the objectives and goals of the research that is being carried out in the Cognitive Systems Engineering Laboratory (CSEL) under a Cooperative Agreement with NASA Ames Research Center is described. The major objective of this project is to expand the research base in Cognitive Engineering to be able to support the development and human-centered design of automated systems for aerospace applications. This research project is in support of the Aviation Safety/Automation Research plan and related NASA research goals in space applications.

  17. Aerospace Medical Support in Russia

    Science.gov (United States)

    Castleberry, Tara; Chamberlin, Blake; Cole, Richard; Dowell, Gene; Savage, Scott

    2011-01-01

    This slide presentation reviews the role of the flight surgeon in support of aerospace medical support operations at the Gagarin Cosmonaut Training Center (GCTC), also known as Star City, in Russia. The flight surgeon in this role is the medical advocate for non-russian astronauts, and also provides medical care for illness and injury for astronauts, family members, and guests as well as civil servants and contractors. The flight surgeon also provides support for hazardous training. There are various photos of the area, and the office, and some of the equipment that is used.

  18. Aerospace Medicine and Biology: A Continuing Bibliography With Indexes. Supplement 497

    Science.gov (United States)

    2000-01-01

    This supplemental issue of Aerospace Medicine and Biology, A Continuing Bibliography with Indexes (NASA/SP#2000-7011) lists reports, articles, and other documents recently announced in the NASA STI Database. In its subject coverage, Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which humans are subjected during and following simulated or actual flight in the Earth's atmosphere or in interplanetary space. References describing similar effects on biological organisms of lower order are also included. Such related topics as sanitary problems, pharmacology, toxicology, safety and survival, life support systems, exobiology, and personnel factors receive appropriate attention.

  19. Analysis and Perspective from the Complex Aerospace Systems Exchange (CASE) 2013

    Science.gov (United States)

    Jones, Kennie H.; Parker, Peter A.; Detweiler, Kurt N.; McGowan, Anna-Maria R.; Dress, David A.; Kimmel, William M.

    2014-01-01

    NASA Langley Research Center embedded four rapporteurs at the Complex Aerospace Systems Exchange (CASE) held in August 2013 with the objective to capture the essence of the conference presentations and discussions. CASE was established to provide a discussion forum among chief engineers, program managers, and systems engineers on challenges in the engineering of complex aerospace systems. The meeting consists of invited presentations and panels from industry, academia, and government followed by discussions among attendees. This report presents the major and reoccurring themes captured throughout the meeting and provides analysis and insights to further the CASE mission.

  20. High performance sealing - meeting nuclear and aerospace requirements

    International Nuclear Information System (INIS)

    Wensel, R.; Metcalfe, R.

    1994-11-01

    Although high performance sealing is required in many places, two industries lead all others in terms of their demand-nuclear and aerospace. The factors that govern the high reliability and integrity of seals, particularly elastomer seals, for both industries are discussed. Aerospace requirements include low structural weight and a broad range of conditions, from the cold vacuum of space to the hot, high pressures of rocket motors. It is shown, by example, how a seal can be made an integral part of a structure in order to improve performance, rather than using a conventional handbook design. Typical processes are then described for selection, specification and procurement of suitable elastomers, functional and accelerated performance testing, database development and service-life prediction. Methods for quality assurance of elastomer seals are summarized. Potentially catastrophic internal dejects are a particular problem for conventional non-destructive inspection techniques. A new method of elastodynamic testing for these is described. (author)

  1. An inexact reverse logistics model for municipal solid waste management systems.

    Science.gov (United States)

    Zhang, Yi Mei; Huang, Guo He; He, Li

    2011-03-01

    This paper proposed an inexact reverse logistics model for municipal solid waste management systems (IRWM). Waste managers, suppliers, industries and distributors were involved in strategic planning and operational execution through reverse logistics management. All the parameters were assumed to be intervals to quantify the uncertainties in the optimization process and solutions in IRWM. To solve this model, a piecewise interval programming was developed to deal with Min-Min functions in both objectives and constraints. The application of the model was illustrated through a classical municipal solid waste management case. With different cost parameters for landfill and the WTE, two scenarios were analyzed. The IRWM could reflect the dynamic and uncertain characteristics of MSW management systems, and could facilitate the generation of desired management plans. The model could be further advanced through incorporating methods of stochastic or fuzzy parameters into its framework. Design of multi-waste, multi-echelon, multi-uncertainty reverse logistics model for waste management network would also be preferred. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Study of liquid phase formation kinetics due to solid/solid chemical interaction and its model. Application to the Zircaloy/Inconel

    International Nuclear Information System (INIS)

    Garcia, E.A.; Denis, A.

    1990-01-01

    A description is made of the chemical interaction between Inconel spacing grids and the Zircaloy of the sheaths. Experiments performed at 1000, 1100 and 1200 deg C with base Zircaloy and with a previously formed layer of ZrO 2 , show that the kinetics is parabolic. The difference between both types of experiments is that the oxide layer delays the initiation of the Inconel-Zry interaction. A model is presented, for the description of the solid/solid interaction, which leads to the formation of eutectic that is liquid at the experiment temperature. Also a model, which represents the oxide layer dissolution and predicts the instant in which it disappears completely, is presented. (Author) [es

  3. A Variational Model for Two-Phase Immiscible Electroosmotic Flow at Solid Surfaces

    KAUST Repository

    Shao, Sihong; Qian, Tiezheng

    2012-01-01

    We develop a continuum hydrodynamic model for two-phase immiscible flows that involve electroosmotic effect in an electrolyte and moving contact line at solid surfaces. The model is derived through a variational approach based on the Onsager

  4. Modelling fungal solid-state fermentation: The role of inactivation kinetics

    NARCIS (Netherlands)

    Smits, J.P.; Sonsbeek, H.M. van; Knol, W.; Tramper, J.; Geelhoed, W.; Peeters, M.; Rinzema, A.

    1999-01-01

    The theoretical mathematical models described in this paper are used to evaluate the effects of fungal biomass inactivation kinetics on a non- isothermal tray solid-state fermentation (SSF). The inactivation kinetics, derived from previously reported experiments done under isothermal conditions and

  5. 76 FR 52016 - NASA International Space Station Advisory Committee and the Aerospace Safety Advisory Panel; Meeting

    Science.gov (United States)

    2011-08-19

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (11-074)] NASA International Space Station Advisory Committee and the Aerospace Safety Advisory Panel; Meeting AGENCY: National Aeronautics and Space... meeting of the NASA International Space Station Advisory Committee and the Aerospace Safety Advisory Panel...

  6. Robust and Adaptive Control With Aerospace Applications

    CERN Document Server

    Lavretsky, Eugene

    2013-01-01

    Robust and Adaptive Control shows the reader how to produce consistent and accurate controllers that operate in the presence of uncertainties and unforeseen events. Driven by aerospace applications the focus of the book is primarily on continuous-dynamical systems.  The text is a three-part treatment, beginning with robust and optimal linear control methods and moving on to a self-contained presentation of the design and analysis of model reference adaptive control (MRAC) for nonlinear uncertain dynamical systems. Recent extensions and modifications to MRAC design are included, as are guidelines for combining robust optimal and MRAC controllers. Features of the text include: ·         case studies that demonstrate the benefits of robust and adaptive control for piloted, autonomous and experimental aerial platforms; ·         detailed background material for each chapter to motivate theoretical developments; ·         realistic examples and simulation data illustrating key features ...

  7. An Analysis of High School Students' Mental Models of Solid Friction in Physics

    Science.gov (United States)

    Kurnaz, Mehmet Altan; Eksi, Cigdem

    2015-01-01

    Students often have difficulties understanding abstract physics concepts, such as solid friction. This study examines high school students' mental models of solid friction through a case study of 215 high school students in the ninth through twelfth grades. An achievement test with three open-ended questions was created, with questions limited to…

  8. Solid foam packings for multiphase reactors: Modelling of liquid holdup and mass transfer

    NARCIS (Netherlands)

    Stemmet, C.P.; Schaaf, van der J.; Kuster, B.F.M.; Schouten, J.C.

    2006-01-01

    In this paper, experimental and modeling results are presented of the liquid holdup and gas–liquid mass transfer characteristics of solid foam packings. Experiments were done in a semi-2D transparent bubble column with solid foam packings of aluminum in the range of 5–40 pores per inch (ppi). The

  9. Axisymmetric Lattice Boltzmann Model of Droplet Impact on Solid Surfaces

    Science.gov (United States)

    Dalgamoni, Hussein; Yong, Xin

    2017-11-01

    Droplet impact is a ubiquitous fluid phenomena encountered in scientific and engineering applications such as ink-jet printing, coating, electronics manufacturing, and many others. It is of great technological importance to understand the detailed dynamics of drop impact on various surfaces. The lattice Boltzmann method (LBM) emerges as an efficient method for modeling complex fluid systems involving rapidly evolving fluid-fluid and fluid-solid interfaces with complex geometries. In this work, we model droplet impact on flat solid substrates with well-defined wetting behavior using a two-phase axisymmetric LBM with high density and viscosity contrasts. We extend the two-dimensional Lee and Liu model to capture axisymmetric effect in the normal impact. First we compare the 2D axisymmetric results with the 2D and 3D results reported by Lee and Liu to probe the effect of axisymmetric terms. Then, we explore the effects of Weber number, Ohnesorge number, and droplet-surface equilibrium contact angle on the impact. The dynamic contact angle and spreading factor of the droplet during impact are investigated to qualitatively characterize the impact dynamics.

  10. A discrete element model for the investigation of the geometrically nonlinear behaviour of solids

    Science.gov (United States)

    Ockelmann, Felix; Dinkler, Dieter

    2018-07-01

    A three-dimensional discrete element model for elastic solids with large deformations is presented. Therefore, an discontinuum approach is made for solids. The properties of elastic material are transferred analytically into the parameters of a discrete element model. A new and improved octahedron gap-filled face-centred cubic close packing of spheres is split into unit cells, to determine the parameters of the discrete element model. The symmetrical unit cells allow a model with equal shear components in each contact plane and fully isotropic behaviour for Poisson's ratio above 0. To validate and show the broad field of applications of the new model, the pin-pin Euler elastica is presented and investigated. The thin and sensitive structure tends to undergo large deformations and rotations with a highly geometrically nonlinear behaviour. This behaviour of the elastica can be modelled and is compared to reference solutions. Afterwards, an improved more realistic simulation of the elastica is presented which softens secondary buckling phenomena. The model is capable of simulating solids with small strains but large deformations and a strongly geometrically nonlinear behaviour, taking the shear stiffness of the material into account correctly.

  11. Modelling of different enzyme productions by solid-state fermentation on several agro-industrial residues.

    Science.gov (United States)

    Diaz, Ana Belen; Blandino, Ana; Webb, Colin; Caro, Ildefonso

    2016-11-01

    A simple kinetic model, with only three fitting parameters, for several enzyme productions in Petri dishes by solid-state fermentation is proposed in this paper, which may be a valuable tool for simulation of this type of processes. Basically, the model is able to predict temporal fungal enzyme production by solid-state fermentation on complex substrates, maximum enzyme activity expected and time at which these maxima are reached. In this work, several fermentations in solid state were performed in Petri dishes, using four filamentous fungi grown on different agro-industrial residues, measuring xylanase, exo-polygalacturonase, cellulose and laccase activities over time. Regression coefficients after fitting experimental data to the proposed model turned out to be quite high in all cases. In fact, these results are very interesting considering, on the one hand, the simplicity of the model and, on the other hand, that enzyme activities correspond to different enzymes, produced by different fungi on different substrates.

  12. Experimental Investigation of Brazilian 14-X B Hypersonic Scramjet Aerospace Vehicle

    Directory of Open Access Journals (Sweden)

    João Felipe de Araujo Martos

    2017-01-01

    Full Text Available The Brazilian hypersonic scramjet aerospace vehicle 14-X B is a technological demonstrator of a hypersonic airbreathing propulsion system based on the supersonic combustion (scramjet to be tested in flight into the Earth’s atmosphere at an altitude of 30 km and Mach number 7. The 14-X B has been designed at the Prof. Henry T. Nagamatsu Laboratory of Aerothermodynamics and Hypersonics, Institute for Advanced Studies (IEAv, Brazil. The IEAv T3 Hypersonic Shock Tunnel is a ground-test facility able to produce high Mach number and high enthalpy flows in the test section close to those encountered during the flight of the 14-X B into the Earth’s atmosphere at hypersonic flight speeds. A 1 m long stainless steel 14-X B model was experimentally investigated at T3 Hypersonic Shock Tunnel, for freestream Mach numbers ranging from 7 to 8. Static pressure measurements along the lower surface of the 14-X B, as well as high-speed Schlieren photographs taken from the 5.5° leading edge and the 14.5° deflection compression ramp, provided experimental data. Experimental data was compared to the analytical theoretical solutions and the computational fluid dynamics (CFD simulations, showing good qualitative agreement and in consequence demonstrating the importance of these methods in the project of the 14-X B hypersonic scramjet aerospace vehicle.

  13. Revision of Paschen's Law Relating to the ESD of Aerospace Vehicle Surfaces

    Science.gov (United States)

    Hogue, Michael D.; Cox, Rachel E.; Mulligan, Jaysen; Kapat, Jayanta; Ahmed, Kareem; Wilson, Jennifer G.; Calle, Luz M.

    2017-01-01

    The purpose of this work is to develop a version of Paschen's law that takes into account the flow of ambient gas past electrode surfaces. Paschen's law does not consider the flow of gas past an aerospace vehicle whose surfaces may be triboelectrically charged by dust or ice crystal impingement while traversing the atmosphere. The basic hypothesis of this work is that the number of electron-ion pairs created per unit distance between electrode surfaces is mitigated by the electron-ion pairs removed per unit distance by the flow of gas. The revised theoretical model must be a function of the mean velocity vxm of the ambient gas and reduce to Paschen's law when the mean velocity is zero. A new theoretical formulation of Paschen's law, taking into account the Mach number and compressible dynamic pressure, derived by the authors, will be discussed. This equation has been evaluated by wind tunnel experimentation. Initial data of the baseline wind tunnel experiments show results consistent with the hypothesis. This work may enhance the safety of aerospace vehicles through a redefinition of electrostatic launch commit criteria. It is also possible for new products, such as antistatic coatings, to be formulated based on this data.

  14. Numerical simulation of ammonium dinitramide (ADN)-based non-toxic aerospace propellant decomposition and combustion in a monopropellant thruster

    International Nuclear Information System (INIS)

    Zhang, Tao; Li, Guoxiu; Yu, Yusong; Sun, Zuoyu; Wang, Meng; Chen, Jun

    2014-01-01

    Highlights: • Decomposition and combustion process of ADN-based thruster are studied. • Distribution of droplets is obtained during the process of spray hit on wire mesh. • Two temperature models are adopted to describe the heat transfer in porous media. • The influences brought by different mass flux and porosity are studied. - Abstract: Ammonium dinitramide (ADN) monopropellant is currently the most promising among all ‘green propellants’. In this paper, the decomposition and combustion process of liquid ADN-based ternary mixtures for propulsion are numerically studied. The R–R distribution model is used to study the initial boundary conditions of droplet distribution resulting from spray hit on a wire mesh based on PDA experiment. To simulate the heat-transfer characteristics between the gas–solid phases, a two-temperature porous medium model in a catalytic bed is used. An 11-species and 7-reactions chemistry model is used to study the catalytic and combustion processes. The final distribution of temperature, pressure, and other kinds of material component concentrations are obtained using the ADN thruster. The results of simulation conducted in the present study are well agree with previous experimental data, and the demonstration of the ADN thruster confirms that a good steady-state operation is achieved. The effects of spray inlet mass flux and porosity on monopropellant thruster performance are analyzed. The numerical results further show that a larger inlet mass flux results in better thruster performance and a catalytic bed porosity value of 0.5 can exhibit the best thruster performance. These findings can serve as a key reference for designing and testing non-toxic aerospace monopropellant thrusters

  15. Interactive Web-Based and Hands-On Engineering Education: A Freshman Aerospace Design Course at MIT.

    Science.gov (United States)

    Newman, Dava J.

    "Introduction to Aerospace and Design" is a 3-hour per week freshman elective course at Massachusetts Institute of Technology (MIT) that culminates in a Lighter-Than-Air (LTA) vehicle design competition, exposing freshmen to the excitement of aerospace engineering design typically taught in the junior or senior years. In addition to the…

  16. The Effects of the Single Process Initiative on Aerospace Subcontractors

    National Research Council Canada - National Science Library

    Winicki, Anthony

    1998-01-01

    .... The methodology used to identify the apparent inequities faced by the subcontractors was a review of current literature and 40 telephone interviews with representatives of aerospace prime contractors and subcontractors...

  17. Replacement Technologies for Precision Cleaning of Aerospace Hardware for Propellant Service

    Science.gov (United States)

    Beeson, Harold; Kirsch, Mike; Hornung, Steven; Biesinger, Paul

    1997-01-01

    The NASA White Sands Test Facility (WSTF) is developing cleaning and verification processes to replace currently used chlorofluorocarbon-l13- (CFC-113-) based processes. The processes being evaluated include both aqueous- and solvent-based techniques. Replacement technologies are being investigated for aerospace hardware and for gauges and instrumentation. This paper includes the findings of investigations of aqueous cleaning and verification of aerospace hardware using known contaminants, such as hydraulic fluid and commonly used oils. The results correlate nonvolatile residue with CFC 113. The studies also include enhancements to aqueous sampling for organic and particulate contamination. Although aqueous alternatives have been identified for several processes, a need still exists for nonaqueous solvent cleaning, such as the cleaning and cleanliness verification of gauges used for oxygen service. The cleaning effectiveness of tetrachloroethylene (PCE), trichloroethylene (TCE), ethanol, hydrochlorofluorocarbon 225 (HCFC 225), HCFC 141b, HFE 7100(R), and Vertrel MCA(R) was evaluated using aerospace gauges and precision instruments and then compared to the cleaning effectiveness of CFC 113. Solvents considered for use in oxygen systems were also tested for oxygen compatibility using high-pressure oxygen autogenous ignition and liquid oxygen mechanical impact testing.

  18. Tissue Acoustoelectric Effect Modeling From Solid Mechanics Theory.

    Science.gov (United States)

    Song, Xizi; Qin, Yexian; Xu, Yanbin; Ingram, Pier; Witte, Russell S; Dong, Feng

    2017-10-01

    The acoustoelectric (AE) effect is a basic physical phenomenon, which underlies the changes made in the conductivity of a medium by the application of focused ultrasound. Recently, based on the AE effect, several biomedical imaging techniques have been widely studied, such as ultrasound-modulated electrical impedance tomography and ultrasound current source density imaging. To further investigate the mechanism of the AE effect in tissue and to provide guidance for such techniques, we have modeled the tissue AE effect using the theory of solid mechanics. Both bulk compression and thermal expansion of tissue are considered and discussed. Computation simulation shows that the muscle AE effect result, conductivity change rate, is 3.26×10 -3 with 4.3-MPa peak pressure, satisfying the theoretical value. Bulk compression plays the main role for muscle AE effect, while thermal expansion makes almost no contribution to it. In addition, the AE signals of porcine muscle are measured at different focal positions. With the same magnitude order and the same change trend, the experiment result confirms that the simulation result is effective. Both simulation and experimental results validate that tissue AE effect modeling using solid mechanics theory is feasible, which is of significance for the further development of related biomedical imaging techniques.

  19. The Role of Computer Networks in Aerospace Engineering.

    Science.gov (United States)

    Bishop, Ann Peterson

    1994-01-01

    Presents selected results from an empirical investigation into the use of computer networks in aerospace engineering based on data from a national mail survey. The need for user-based studies of electronic networking is discussed, and a copy of the questionnaire used in the survey is appended. (Contains 46 references.) (LRW)

  20. Managing human fallibility in critical aerospace situations

    Science.gov (United States)

    Tew, Larry

    2014-11-01

    Human fallibility is pervasive in the aerospace industry with over 50% of errors attributed to human error. Consider the benefits to any organization if those errors were significantly reduced. Aerospace manufacturing involves high value, high profile systems with significant complexity and often repetitive build, assembly, and test operations. In spite of extensive analysis, planning, training, and detailed procedures, human factors can cause unexpected errors. Handling such errors involves extensive cause and corrective action analysis and invariably schedule slips and cost growth. We will discuss success stories, including those associated with electro-optical systems, where very significant reductions in human fallibility errors were achieved after receiving adapted and specialized training. In the eyes of company and customer leadership, the steps used to achieve these results lead to in a major culture change in both the workforce and the supporting management organization. This approach has proven effective in other industries like medicine, firefighting, law enforcement, and aviation. The roadmap to success and the steps to minimize human error are known. They can be used by any organization willing to accept human fallibility and take a proactive approach to incorporate the steps needed to manage and minimize error.