WorldWideScience

Sample records for improve aircraft maintenance

  1. AIRCRAFT MAINTENANCE HANGAR

    National Research Council Canada - National Science Library

    GEAMBASU Gabriel George

    2017-01-01

    .... The first part of research describes the aircraft maintenance process that has to be done after an updated maintenance manual according with aircraft type, followed by a short introduction about maintenance hangar...

  2. A performance improvement case study in aircraft maintenance and its implications for hazard identification.

    Science.gov (United States)

    Ward, Marie; McDonald, Nick; Morrison, Rabea; Gaynor, Des; Nugent, Tony

    2010-02-01

    Aircraft maintenance is a highly regulated, safety critical, complex and competitive industry. There is a need to develop innovative solutions to address process efficiency without compromising safety and quality. This paper presents the case that in order to improve a highly complex system such as aircraft maintenance, it is necessary to develop a comprehensive and ecologically valid model of the operational system, which represents not just what is meant to happen, but what normally happens. This model then provides the backdrop against which to change or improve the system. A performance report, the Blocker Report, specific to aircraft maintenance and related to the model was developed gathering data on anything that 'blocks' task or check performance. A Blocker Resolution Process was designed to resolve blockers and improve the current check system. Significant results were obtained for the company in the first trial and implications for safety management systems and hazard identification are discussed. Statement of Relevance: Aircraft maintenance is a safety critical, complex, competitive industry with a need to develop innovative solutions to address process and safety efficiency. This research addresses this through the development of a comprehensive and ecologically valid model of the system linked with a performance reporting and resolution system.

  3. AIRCRAFT MAINTENANCE HANGAR

    Directory of Open Access Journals (Sweden)

    GEAMBASU Gabriel George

    2017-05-01

    Full Text Available The paper presents the maintenance process that is done on an airplane, at a certain period of time, or after a number of flight hours or cycles and describes the checks performed behind each inspection. The first part of research describes the aircraft maintenance process that has to be done after an updated maintenance manual according with aircraft type, followed by a short introduction about maintenance hangar. The second part of the paper presents a hangar design with a foldable roof and walls, which can be folded or extended, over an airplane when a maintenance process is done, or depending on weather condition.

  4. GRAPHICAL MODELS OF THE AIRCRAFT MAINTENANCE PROCESS

    Directory of Open Access Journals (Sweden)

    Stanislav Vladimirovich Daletskiy

    2017-01-01

    Full Text Available The aircraft maintenance is realized by a rapid sequence of maintenance organizational and technical states, its re- search and analysis are carried out by statistical methods. The maintenance process concludes aircraft technical states con- nected with the objective patterns of technical qualities changes of the aircraft as a maintenance object and organizational states which determine the subjective organization and planning process of aircraft using. The objective maintenance pro- cess is realized in Maintenance and Repair System which does not include maintenance organization and planning and is a set of related elements: aircraft, Maintenance and Repair measures, executors and documentation that sets rules of their interaction for maintaining of the aircraft reliability and readiness for flight. The aircraft organizational and technical states are considered, their characteristics and heuristic estimates of connection in knots and arcs of graphs and of aircraft organi- zational states during regular maintenance and at technical state failure are given. It is shown that in real conditions of air- craft maintenance, planned aircraft technical state control and maintenance control through it, is only defined by Mainte- nance and Repair conditions at a given Maintenance and Repair type and form structures, and correspondingly by setting principles of Maintenance and Repair work types to the execution, due to maintenance, by aircraft and all its units mainte- nance and reconstruction strategies. The realization of planned Maintenance and Repair process determines the one of the constant maintenance component. The proposed graphical models allow to reveal quantitative correlations between graph knots to improve maintenance processes by statistical research methods, what reduces manning, timetable and expenses for providing safe civil aviation aircraft maintenance.

  5. Robots for Aircraft Maintenance

    Science.gov (United States)

    1993-01-01

    Marshall Space Flight Center charged USBI (now Pratt & Whitney) with the task of developing an advanced stripping system based on hydroblasting to strip paint and thermal protection material from Space Shuttle solid rocket boosters. A robot, mounted on a transportable platform, controls the waterjet angle, water pressure and flow rate. This technology, now known as ARMS, has found commercial applications in the removal of coatings from jet engine components. The system is significantly faster than manual procedures and uses only minimal labor. Because the amount of "substrate" lost is minimal, the life of the component is extended. The need for toxic chemicals is reduced, as is waste disposal and human protection equipment. Users of the ARMS work cell include Delta Air Lines and the Air Force, which later contracted with USBI for development of a Large Aircraft Paint Stripping system (LARPS). LARPS' advantages are similar to ARMS, and it has enormous potential in military and civil aircraft maintenance. The technology may also be adapted to aircraft painting, aircraft inspection techniques and paint stripping of large objects like ships and railcars.

  6. Quality standard of aircraft maintenance

    Directory of Open Access Journals (Sweden)

    Боузаієнне Меккі бен Салем

    2005-01-01

    Full Text Available  The question of the account of operation conditions of an aeronautical engineering in airlines is considered at formation and a correcting of plans on aircrafts park maintenance.

  7. Automation tools for flexible aircraft maintenance.

    Energy Technology Data Exchange (ETDEWEB)

    Prentice, William J.; Drotning, William D.; Watterberg, Peter A.; Loucks, Clifford S.; Kozlowski, David M.

    2003-11-01

    This report summarizes the accomplishments of the Laboratory Directed Research and Development (LDRD) project 26546 at Sandia, during the period FY01 through FY03. The project team visited four DoD depots that support extensive aircraft maintenance in order to understand critical needs for automation, and to identify maintenance processes for potential automation or integration opportunities. From the visits, the team identified technology needs and application issues, as well as non-technical drivers that influence the application of automation in depot maintenance of aircraft. Software tools for automation facility design analysis were developed, improved, extended, and integrated to encompass greater breadth for eventual application as a generalized design tool. The design tools for automated path planning and path generation have been enhanced to incorporate those complex robot systems with redundant joint configurations, which are likely candidate designs for a complex aircraft maintenance facility. A prototype force-controlled actively compliant end-effector was designed and developed based on a parallel kinematic mechanism design. This device was developed for demonstration of surface finishing, one of many in-contact operations performed during aircraft maintenance. This end-effector tool was positioned along the workpiece by a robot manipulator, programmed for operation by the automated planning tools integrated for this project. Together, the hardware and software tools demonstrate many of the technologies required for flexible automation in a maintenance facility.

  8. Improving Legacy Aircraft Systems Through Condition-Based Maintenance: An H-60 Case Study

    Science.gov (United States)

    2014-09-01

    helicopter operated by the Marine Corps. The AH-1W/Z “ Cobra ” uses a CBM cycle and has its PMI is two 36-month cycles with maintenance cued from condition...satisfy the JCIDS CBA discussed in Chapter IV. The baseline forms the heart of the capability gap analysis and was used to measure the value of a

  9. An integrated approach for modelling of aircraft maintenance processes

    Directory of Open Access Journals (Sweden)

    D. Yu. Kiselev

    2015-01-01

    Full Text Available The paper deals with modeling of the processes of maintenance and repair of aircraft. The role of information in im-proving the effectiveness of maintenance systems is described. The methodology for functional modelling of maintenance processes is given. A simulation model is used for modelling possible changes.

  10. A Qualitative Analysis of SAC Aircraft Maintenance.

    Science.gov (United States)

    1982-09-01

    A122 815 A QUALITATIVE ANALYSIS OF SAC AIRCRAFT MRINTENANCE(U) 112 AIR FORCE INST OF TECH WRIGHT-PRTTERSON AFB OH SCHOOL OF SYSTEMS AND LOGISTICS D...Wright-Patterson Air Force Base, Ohio ’ ; " ... ..... ... ... . .. .. A QUALITATIVE ANALYSIS OF SAC AIRCRAFT MAINTENANCE Douglas P. Cook, Captain... QUALITATIVE ANALYSIS OF SAC Master’s Thesis AIRCRAFT MAINTENANCE 6. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(q) S. CONTRACT OR GRANT NUMBER(a) Douglas

  11. Human factors in aircraft maintenance and inspection

    Science.gov (United States)

    Shepherd, William T.

    1992-01-01

    The events which have led to the intensive study of aircraft structural problems have contributed in no less measure to the study of human factors which influence aircraft maintenance and inspection. Initial research emphasis on aging aircraft maintenance and inspection has since broadened to include all aircraft types. Technicians must be equally adept at repairing old and new aircraft. Their skills must include the ability to repair sheet metal and composite materials; control cable and fly-by-wire systems; round dials and glass cockpits. Their work performance is heavily influenced by others such as designers, technical writers, job card authors, schedulers, and trainers. This paper describes the activities concerning aircraft and maintenance human factors.

  12. Aircraft Electronics Maintenance Training Simulator. Curriculum Outlines.

    Science.gov (United States)

    Blackhawk Technical Coll., Janesville, WI.

    Instructional materials are provided for nine courses in an aircraft electronics maintenance training program. Courses are as follows: aviation basic electricity, direct current and alternating current electronics, basic avionic installations, analog electronics, digital electronics, microcomputer electronics, radio communications, aircraft…

  13. Maintenance cost study of rotary wing aircraft

    Science.gov (United States)

    1977-01-01

    The feasibility was studied of predicting rotary wing operation maintenance costs by using several aircraft design factors for the aircraft dynamic systems. The dynamic systems considered were engines, drives and transmissions, rotors, and flight controls. Multiple regression analysis was used to correlate aircraft design and operational factors with manhours per flight hour, and equations for each dynamic system were developed. Results of labor predictions using the equations compare favorably with actual values.

  14. 14 CFR 183.27 - Designated aircraft maintenance inspectors.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Designated aircraft maintenance inspectors...: Privileges § 183.27 Designated aircraft maintenance inspectors. A designated aircraft maintenance inspector (DAMI) may approve maintenance on civil aircraft used by United States military flying clubs in foreign...

  15. Global Outsourcing of Aircraft Maintenance

    OpenAIRE

    McFadden, Michael; Worrells, D. Scott

    2012-01-01

    Before the airlines were deregulated, the majority of air carriers conducted their maintenance in-house. After deregulation, with competitive pressures mounting and airlines failing and starting up seemingly simultaneously, the outsourcing of maintenance became more prevalent. Not restricted to U.S. airlines, outsourcing maintenance has become a global practice. Factors involved in the outsourcing decision range from a startup not having the capital to develop their own in-house maintenance p...

  16. A Grounded Theory Study of Aircraft Maintenance Technician Decision-Making

    Science.gov (United States)

    Norcross, Robert

    Aircraft maintenance technician decision-making and actions have resulted in aircraft system errors causing aircraft incidents and accidents. Aircraft accident investigators and researchers examined the factors that influence aircraft maintenance technician errors and categorized the types of errors in an attempt to prevent similar occurrences. New aircraft technology introduced to improve aviation safety and efficiency incur failures that have no information contained in the aircraft maintenance manuals. According to the Federal Aviation Administration, aircraft maintenance technicians must use only approved aircraft maintenance documents to repair, modify, and service aircraft. This qualitative research used a grounded theory approach to explore the decision-making processes and actions taken by aircraft maintenance technicians when confronted with an aircraft problem not contained in the aircraft maintenance manuals. The target population for the research was Federal Aviation Administration licensed aircraft and power plant mechanics from across the United States. Nonprobability purposeful sampling was used to obtain aircraft maintenance technicians with the experience sought in the study problem. The sample population recruitment yielded 19 participants for eight focus group sessions to obtain opinions, perceptions, and experiences related to the study problem. All data collected was entered into the Atlas ti qualitative analysis software. The emergence of Aircraft Maintenance Technician decision-making themes regarding Aircraft Maintenance Manual content, Aircraft Maintenance Technician experience, and legal implications of not following Aircraft Maintenance Manuals surfaced. Conclusions from this study suggest Aircraft Maintenance Technician decision-making were influenced by experience, gaps in the Aircraft Maintenance Manuals, reliance on others, realizing the impact of decisions concerning aircraft airworthiness, management pressures, and legal concerns

  17. 14 CFR 91.1109 - Aircraft maintenance: Inspection program.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft maintenance: Inspection program... Ownership Operations Program Management § 91.1109 Aircraft maintenance: Inspection program. Each program manager must establish an aircraft inspection program for each make and model program aircraft and ensure...

  18. Licencing and Training Reform in the Australian Aircraft Maintenance Industry

    Science.gov (United States)

    Hampson, Ian; Fraser, Doug

    2016-01-01

    The training and licencing of aircraft maintenance engineers fulfils a crucial protective function since it is they who perform and supervise aircraft maintenance and certify that planes are safe afterwards. In Australia, prior to training reform, a trades-based system of aircraft maintenance engineer training existed in an orderly relation with…

  19. Licencing and Training Reform in the Australian Aircraft Maintenance Industry

    Science.gov (United States)

    Hampson, Ian; Fraser, Doug

    2016-01-01

    The training and licencing of aircraft maintenance engineers fulfils a crucial protective function since it is they who perform and supervise aircraft maintenance and certify that planes are safe afterwards. In Australia, prior to training reform, a trades-based system of aircraft maintenance engineer training existed in an orderly relation with…

  20. Optimization parameters system maintenance transport aircraft

    Directory of Open Access Journals (Sweden)

    І.І. Ліннік

    2006-01-01

    Full Text Available  The algorithm of unconditional and conditional optimization Markov models of maintenance systems of transport airplanes of their programs of technical operation used at improvement is considered.

  1. Business Process Reengineering in the Inventory Management to Improve Aircraft Maintenance Operations in the Indonesian Air Force

    Science.gov (United States)

    2006-06-01

    from the warehouse. JIT was used by the Ford Motor Company in the early 1920s before being adopted and publicized by the Toyota Motor Company ...industries in many countries, such as Kawasaki Motor Corp., Chrysler, Hyundai , General Electric, Hewlett- Master Production Schedule MRP System...for the helicopter immediately needed for a certain mission also can be purchased from the local aircraft company which operates the same helicopter

  2. Final Environmental Assessment for Aircraft Maintenance Operations Center

    Science.gov (United States)

    2014-06-01

    Historic Preservation Act AIRFA American Indian Religious Freedom Act AMC Aircraft Maintenance Contractor AMOC Aircraft Maintenance Operations...this document. Table 1-1 Applicable Environmental Laws and Regulations Federal Statutes and Policies American Indian Religious Freedom Act (AIRFA...Larks (Eremophila alpestris), Common Grackle (Quiscula quiscala), American Crow (Corvus brachyrhynchos), Turkey Vulture (Cathartes aura), Black Vulture

  3. A DSS for capacity planning of aircraft maintenance personnel

    NARCIS (Netherlands)

    M.C. Dijkstra (Matthijs); L.G. Kroon (Leo); J.A.E.E. van Nunen (Jo); M. Salomon (Marc)

    1991-01-01

    textabstractIn this paper we describe a Decision Support System (DSS) that has been developed for the aircraft maintenance department of the Dutch national airline company at the main airport in the Netherlands. The aircraft maintenance department is responsible for carrying out the regular short in

  4. A Study on Simulation of Aircraft Maintenance and Support System

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Maintenance and support are basic elements to realize the effectiveness of aircraft. For basic analysis of the characteristics of an aircraft maintenance and support system, a simulation method is presented in this paper, and the structure and realization ofthe simulation system is discussed.

  5. A DSS for capacity planning of aircraft maintenance personnel

    NARCIS (Netherlands)

    M.C. Dijkstra (Matthijs); L.G. Kroon (Leo); J.A.E.E. van Nunen (Jo); M. Salomon (Marc)

    1991-01-01

    textabstractIn this paper we describe a Decision Support System (DSS) that has been developed for the aircraft maintenance department of the Dutch national airline company at the main airport in the Netherlands. The aircraft maintenance department is responsible for carrying out the regular short

  6. 14 CFR 121.701 - Maintenance log: Aircraft.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintenance log: Aircraft. 121.701 Section... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Records and Reports § 121.701 Maintenance log... have made, a record of that action in the airplane's maintenance log. (b) Each certificate holder...

  7. Improving industrial maintenance contract relationships

    NARCIS (Netherlands)

    De Jong, A.

    2010-01-01

    Unavailability of technical systems, such as aircraft, is expensive. Technical systems require maintenance to prevent and to remedy defects that cause unavailability. Users of technical systems usually bear the consequences of the risk of unavailability, in particular the loss of productivity. This

  8. Improving industrial maintenance contract relationships

    NARCIS (Netherlands)

    De Jong, A.

    2010-01-01

    Unavailability of technical systems, such as aircraft, is expensive. Technical systems require maintenance to prevent and to remedy defects that cause unavailability. Users of technical systems usually bear the consequences of the risk of unavailability, in particular the loss of productivity. This

  9. Space shuttle recommendations based on aircraft maintenance experience

    Science.gov (United States)

    Spears, J. M.; Fox, C. L.

    1972-01-01

    Space shuttle design recommendations based on aircraft maintenance experience are developed. The recommendations are specifically applied to the landing gear system, nondestructive inspection techniques, hydraulic system design, materials and processes, and program support.

  10. Aircraft maintenance. Citations from the International Aerospace Abstracts data base

    Science.gov (United States)

    Zollars, G. F.

    1980-01-01

    These citations from the international literature concern various aspects of aircraft maintenance. Both military and civil aviation experience are included. Articles cited concern airline operations, engine and avionics reliability, the use of automatic test equipment, maintenance scheduling, and reliability engineering. This updated bibliography contains 347 citations, 85 of which are new additions to the previous edition.

  11. Maintenance of air worthiness of aircrafts

    Directory of Open Access Journals (Sweden)

    В. А. Горячев

    2000-09-01

    Full Text Available Described are modem conditions of operation of Russian civil aviation, state of aircraft stock, the main principles of maintaining air worthiness of airplanes and helicopters. Considered is a stage by stage prolongation of the service life of each specimen of aircraft with certification being obligatory

  12. The Influence of Human Factor in Aircraft Maintenance

    Directory of Open Access Journals (Sweden)

    Darko Virovac

    2017-06-01

    during aircraft maintenance. In the EASA approved aircraft maintenance organisation, which includes in its working system the human factor as well, the tendency is to apply the approach by continuous monitoring and analysis of errors in aircraft maintenance. Such approach achieves advance prevention or reduction of the occurrence of harmful events, such as accidents, incidents, injuries and in a wider sense damages related to aircraft operation and maintenance. The research presented in this paper is a result of gathering and systematization of errors caused by human factors over the last five years in one organisation for aircraft maintenance certified according to the European standards. The study encompasses an analysis of 28 (twenty-eight investigations of individual cases and provides insight into the main factors of errors. The results of analyses on the cause of occurrence of human error show similar results like the Boeing study which was carried out for the world fleet.

  13. Structural risk assessment and aircraft fleet maintenance

    Science.gov (United States)

    Smith, Herb, Jr.; Saff, C. R.; Christian, Tom F.

    1990-01-01

    In the present analysis, deterministic flaw growth analysis is used to project the failure distributions from inspection data. Inspection data is reported for each critical point in the aircraft. The data will indicate either a crack of a specific size or no crack. The crack length may be either less than, equal to, or greater than critical size for that location. Non-critical length cracks are projected to failure using the crack growth characteristics for that location to find the life when it will be at critical length. Greater-than-critical length cracks are projected back to determine the life at failure, that is, when it was at critical length. The same process is used as in the case of a non-critical crack except that the projection goes the other direction. These points, along with the critical length cracks are used to determine the failure distribution. To be able to use data from different aircraft to build a common failure distribution, a consistent life variable must be used. Aircraft life varies with the severity of the usage; therefore the number of flight hours for a particular aircraft must be modified by its usage factor to obtain a normalized life which can be compared with that from other aircraft.

  14. Application of Artificial Neural Networks in Aircraft Maintenance, Repair and Overhaul Solutions

    CERN Document Server

    Paul, Soumitra; Jasani, Devashish; Dudhwewala, Rachit; Gowda, Vijay Bore; Nair, T R Gopalakrishnan

    2010-01-01

    This paper reviews application of Artificial Neural Networks in Aircraft Maintenance, Repair and Overhaul (MRO). MRO solutions are designed to facilitate the authoring and delivery of maintenance and repair information to the line maintenance technicians who need to improve aircraft repair turn around time, optimize the efficiency and consistency of fleet maintenance and ensure regulatory compliance. The technical complexity of aircraft systems, especially in avionics, has increased to the point at which it poses a significant troubleshotting and repair challenge for MRO personnel. As per the existing scenario, the MRO systems in place are inefficient. In this paper, we propose the centralization and integration of the MRO database to increase its efficiency. Moreover the implementation of Artificial Neural Networks in this system can rid the system of many of its deficiencies. In order to make the system more efficient we propose to integrate all the modules so as to reduce the efficacy of repair.

  15. Aviation Maintenance Technology. General. G102 Fundamentals of Aircraft Maintenance. Instructor Material.

    Science.gov (United States)

    Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    These instructor materials for an aviation maintenance technology course contain four instructional modules. The modules cover the following topics: identifying basic components of aircraft, performing aircraft cleaning and corrosion control, interpreting blueprints and drawing sketches, identifying structural materials, and performing basic…

  16. Corrosion Sensor Development for Condition-Based Maintenance of Aircraft

    Directory of Open Access Journals (Sweden)

    Gino Rinaldi

    2012-01-01

    Full Text Available Aircraft routinely operate in atmospheric environments that, over time, will impact their structural integrity. Material protection and selection schemes notwithstanding, recurrent exposure to chlorides, pollution, temperature gradients, and moisture provide the necessary electrochemical conditions for the development and profusion of corrosion in aircraft structures. For aircraft operators, this becomes an important safety matter as corrosion found in a given aircraft must be assumed to be present in all of that type of aircraft. This safety protocol and its associated unscheduled maintenance requirement drive up the operational costs of the fleet and limit the availability of the aircraft. Hence, there is an opportunity at present for developing novel sensing technologies and schemes to aid in shifting time-based maintenance schedules towards condition-based maintenance procedures. In this work, part of the ongoing development of a multiparameter integrated corrosion sensor is presented. It consists of carbon nanotube/polyaniline polymer sensors and commercial-off-the-shelf sensors. It is being developed primarily for monitoring environmental and material factors for the purpose of providing a means to more accurately assess the structural integrity of aerospace aluminium alloys through fusion of multiparameter sensor data. Preliminary experimental test results are presented for chloride ion concentration, hydrogen gas evolution, humidity variations, and material degradation.

  17. Availability of Aircraft Subject to Imperfect Preventive Maintenance

    Science.gov (United States)

    1990-09-01

    maintenance model for determining an improved preventive maintenance policy, and the strength of simulating the operating environment when determining... preventive maintenance schedule and the use of simulation as a driver for the model. For those systems that are subject to preventive maintenance, the model...decrease in effectiveness. It further looks at the feasibility of using an imperfect preventive maintenance model for determining an improved

  18. Maintenance cost study of rotary wing aircraft, phase 2

    Science.gov (United States)

    1979-01-01

    The Navy's maintenance and materials management data base was used in a study to determine the feasibility of predicting unscheduled maintenance costs for the dynamic systems of military rotary wing aircraft. The major operational and design variables were identified and the direct maintenance man hours per flight hour were obtained by step-wise multiple regression analysis. Five nonmilitary helicopter users were contacted to supply data on which variables were important factors in civil applications. These uses included offshore oil exploration and support, police and fire department rescue and enforcement, logging and heavy equipment movement, and U.S. Army military operations. The equations developed were highly effective in predicting unscheduled direct maintenance man hours per flying hours for military aircraft, but less effective for commercial or public service helicopters, probably because of the longer mission durations and the much higher utilization of civil users.

  19. Modern Communication Devices in the General Aviation Aircraft Maintenance

    Directory of Open Access Journals (Sweden)

    Martin Novák

    2016-01-01

    Full Text Available The purpose of this article is to design a software that enables an integration of modern communication devices in the process of general aviation aircraft maintenance. The theoretical part deals with the legislative requirements of both maintenance and management processes for continuing airworthiness. The practical part focusses on software design and automation of the processes. An important part of the article is a chapter about economic evaluation based on the proposal of the solution.

  20. Quality Requirements Regarding Aircraft Maintenance and Repair Services

    Directory of Open Access Journals (Sweden)

    Woźny Piotr

    2014-12-01

    Full Text Available During operation, aircraft (AC are subject to use, maintenance, repair and disposal. Each of those processes requires adequate quality. This study presents requirements related to quality management with which an AC maintenance and repair sub-system ought to comply. Documents containing requirements pertaining to both management and technical aspects have been analysed. Applicable standards and regulations affecting the AC repair process quality assurance have been presented. A description of standards observance of which is required to ensure effective operation of modern AC maintenance and repair subsystems significantly affecting maintenance of the AC required airworthiness has been included. Complexity of the decision-taking process pertaining to AC maintenance and repair within the airworthiness maintenance sub-system has been presented

  1. An optimization method for condition based maintenance of aircraft fleet considering prognostics uncertainty.

    Science.gov (United States)

    Feng, Qiang; Chen, Yiran; Sun, Bo; Li, Songjie

    2014-01-01

    An optimization method for condition based maintenance (CBM) of aircraft fleet considering prognostics uncertainty is proposed. The CBM and dispatch process of aircraft fleet is analyzed first, and the alternative strategy sets for single aircraft are given. Then, the optimization problem of fleet CBM with lower maintenance cost and dispatch risk is translated to the combinatorial optimization problem of single aircraft strategy. Remain useful life (RUL) distribution of the key line replaceable Module (LRM) has been transformed into the failure probability of the aircraft and the fleet health status matrix is established. And the calculation method of the costs and risks for mission based on health status matrix and maintenance matrix is given. Further, an optimization method for fleet dispatch and CBM under acceptable risk is proposed based on an improved genetic algorithm. Finally, a fleet of 10 aircrafts is studied to verify the proposed method. The results shows that it could realize optimization and control of the aircraft fleet oriented to mission success.

  2. Planning the Size and Organization of KLM's Aircraft Maintenance Personnel

    NARCIS (Netherlands)

    M.C. Dijkstra (Matthijs); L.G. Kroon (Leo); M. Salomon (Marc); J.A.E.E. van Nunen (Jo); L.N. van Wassenhove (Luk)

    1994-01-01

    textabstractDevelops a decision support system (DSS) for the aircraft maintenance department of KLM Royal Dutch Airlines at Schiphol Airport in Amsterdam, Netherlands. Tasks of the department; Support provided by the DSS to management; Analyzing several capacity planning problems related to the size

  3. A Telerobotics Architecture for Aircraft Maintenance and Remanufacturing

    Science.gov (United States)

    Backes, P. G.; Zimmerman, W.; Leahy, M. B., Jr.

    1994-01-01

    The application of telerobotics to aircraft depot maintenance and remanufacturing is described and a telerobotics architecture for the application is discussed. Telerobotics will enhance process quality and could potentially decrease turn-around time and costs while moving human operatiors from hazardous work areas to safe and comfortable operator control stations.

  4. Examining the Relationship Between Passenger Airline Aircraft Maintenance Outsourcing and Aircraft Safety

    Science.gov (United States)

    Monaghan, Kari L.

    The problem addressed was the concern for aircraft safety rates as they relate to the rate of maintenance outsourcing. Data gathered from 14 passenger airlines: AirTran, Alaska, America West, American, Continental, Delta, Frontier, Hawaiian, JetBlue, Midwest, Northwest, Southwest, United, and USAir covered the years 1996 through 2008. A quantitative correlational design, utilizing Pearson's correlation coefficient, and the coefficient of determination were used in the present study to measure the correlation between variables. Elements of passenger airline aircraft maintenance outsourcing and aircraft accidents, incidents, and pilot deviations within domestic passenger airline operations were analyzed, examined, and evaluated. Rates of maintenance outsourcing were analyzed to determine the association with accident, incident, and pilot deviation rates. Maintenance outsourcing rates used in the evaluation were the yearly dollar expenditure of passenger airlines for aircraft maintenance outsourcing as they relate to the total airline aircraft maintenance expenditures. Aircraft accident, incident, and pilot deviation rates used in the evaluation were the yearly number of accidents, incidents, and pilot deviations per miles flown. The Pearson r-values were calculated to measure the linear relationship strength between the variables. There were no statistically significant correlation findings for accidents, r(174)=0.065, p=0.393, and incidents, r(174)=0.020, p=0.793. However, there was a statistically significant correlation for pilot deviation rates, r(174)=0.204, p=0.007 thus indicating a statistically significant correlation between maintenance outsourcing rates and pilot deviation rates. The calculated R square value of 0.042 represents the variance that can be accounted for in aircraft pilot deviation rates by examining the variance in aircraft maintenance outsourcing rates; accordingly, 95.8% of the variance is unexplained. Suggestions for future research include

  5. Hierarchical Colored Timed Petri Nets for Maintenance Process Modeling of Civil Aircraft

    Institute of Scientific and Technical Information of China (English)

    FU Cheng-cheng; SUN You-chao; LU Zhong

    2008-01-01

    Civil aircraft maintenance process simulation model is an effective method for analyzing the maintainability of a civil aircraft. First, we present the Hierarchical Colored Timed Petri Nets for maintenance process modeling of civil aircraft. Then, we expound a general method of civil aircraft maintenance activities, determine the maintenance level for decomposition, and propose the methods of describing logic of relations between the maintenance activities based on Petri Net. Finally, a time Colored Petri multi-level network modeling and simulation procedures and steps are given with the maintenance example of the landing gear burst tire of a certain type of aircraft. The feasibility of the method is proved by the example.

  6. 40 CFR 141.804 - Aircraft water system operations and maintenance plan.

    Science.gov (United States)

    2010-07-01

    ...) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Aircraft Drinking Water Rule § 141.804 Aircraft water system operations and maintenance plan. (a) Each air carrier must develop and implement an aircraft water system operations and maintenance plan for each aircraft water system that it...

  7. 14 CFR 135.443 - Airworthiness release or aircraft maintenance log entry.

    Science.gov (United States)

    2010-01-01

    ... maintenance log entry. 135.443 Section 135.443 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... release or aircraft maintenance log entry. (a) No certificate holder may operate an aircraft after... (2) An appropriate entry in the aircraft maintenance log. (b) The airworthiness release or log...

  8. Unsafe acts and unsafe outcomes in aircraft maintenance

    Science.gov (United States)

    Hobbs, Alan; Williamson, Ann

    2002-01-01

    Road safety studies using the Driver Behaviour Questionnaire (DBQ) have provided support for a three-way distinction between violations, skill-based errors and mistakes, and have indicated that a tendency to commit driving violations is associated with an increased risk of accident involvement. The aims of this study were to examine whether the three-way distinction of unsafe acts is applicable in the context of aircraft maintenance, and whether involvement in maintenance safety occurrences can be predicted on the basis of self-reported unsafe acts. A Maintenance Behaviour Questionnaire (MBQ) was developed to explore patterns of unsafe acts committed by aircraft maintenance mechanics. The MBQ was completed anonymously by over 1300 Australian aviation mechanics, who also provided information on their involvement in workplace accidents and incidents. Four factors were identified: routine violations, skill-based errors, mistakes and exceptional violations. Violations and mistakes were related significantly to the occurrence of incidents that jeopardized the quality of aircraft maintenance, but were not related to workplace injuries. Skill-based errors, while not related to work quality incidents, were related to workplace injuries. The results are consistent with the three-way typology of unsafe acts described by Reason et al. (1990) and with the DBQ research indicating an association between self-reported violations and accidents. The current findings suggest that interventions addressed at maintenance quality incidents should take into account the role of violations and mistakes, and the factors that promote them. In contrast, interventions directed at reducing workplace injury are likely to require a focus on skill-based errors.

  9. Aircraft Scheduled Airframe Maintenance and Downtime Integrated Cost Model

    Directory of Open Access Journals (Sweden)

    Remzi Saltoğlu

    2016-01-01

    Full Text Available Aviation industry has grown rapidly since the first scheduled commercial aviation started one hundred years ago. There is a fast growth in the number of passengers, routes, and frequencies, with high revenues and low margins, which make this industry one of the most challenging businesses in the world. Every operator aims to undertake the minimum operating cost and gain profit as much as possible. One of the significant elements of operator’s operating cost is the maintenance cost. During maintenance scheduling, operator calculates the maintenance cost that it needs to budget. Previous works show that this calculation includes only costs that are directly related to the maintenance process such as cost of labor, material, and equipment. In some cases, overhead cost is also included. Some of previous works also discuss the existence of another cost throughout aircraft downtime, which is defined as cost of revenue loss. Nevertheless, there is not any standard model that shows how to define and calculate downtime cost. For that reason, the purpose of this paper is to introduce a new model and analysis technique that can be used to calculate aircraft downtime cost due to maintenance.

  10. Immersive Learning Simulations in Aircraft Maintenance Training

    Science.gov (United States)

    2010-02-15

    You might just get a “serious game,” or “as proposed by the eLearning Guild, you could get an Immersive Learning Simulation.”3 Quoting the... eLearning Guild, Caspian Learning, in a report for the United Kingdom Ministry of Defense, defined an Immersive Learning Simulation (ILS) as “an optimized...their studies that “the savings are more likely to be achieved, and the improvements in training quality more easily justified, when technology is

  11. Identifying Human Factors Issues in Aircraft Maintenance Operations

    Science.gov (United States)

    Veinott, Elizabeth S.; Kanki, Barbara G.; Shafto, Michael G. (Technical Monitor)

    1995-01-01

    Maintenance operations incidents submitted to the Aviation Safety Reporting System (ASRS) between 1986-1992 were systematically analyzed in order to identify issues relevant to human factors and crew coordination. This exploratory analysis involved 95 ASRS reports which represented a wide range of maintenance incidents. The reports were coded and analyzed according to the type of error (e.g, wrong part, procedural error, non-procedural error), contributing factors (e.g., individual, within-team, cross-team, procedure, tools), result of the error (e.g., aircraft damage or not) as well as the operational impact (e.g., aircraft flown to destination, air return, delay at gate). The main findings indicate that procedural errors were most common (48.4%) and that individual and team actions contributed to the errors in more than 50% of the cases. As for operational results, most errors were either corrected after landing at the destination (51.6%) or required the flight crew to stop enroute (29.5%). Interactions among these variables are also discussed. This analysis is a first step toward developing a taxonomy of crew coordination problems in maintenance. By understanding what variables are important and how they are interrelated, we may develop intervention strategies that are better tailored to the human factor issues involved.

  12. Aircraft Route Recovery Based on An Improved GRASP Method

    Directory of Open Access Journals (Sweden)

    Yang He

    2017-01-01

    Full Text Available Aircrafts maintenance, temporary airport closures are common factors that disrupt normal flight schedule. The aircraft route recovery aims to recover original schedules by some strategies, including flights swaps, and cancellations, which is a NP-hard problem. This paper proposes an improved heuristic procedure based on Greedy Random Adaptive Search Procedure (GRASP to solve this problem. The effectiveness and high global optimization capability of the heuristic is illustrated through experiments based on large-scale problems. Compared to the original one, it is shown that the improved procedure can find feasible flight recovered schedules with lower cost in a short time.

  13. Awareness grows of importance of human factors issues in aircraft maintenance and inspection.

    Science.gov (United States)

    1996-01-01

    Until recently, the role of human factors in maintenance operations was not adequately addressed. That is changing, because it is clear that human error in aircraft maintenance can have a serious impact on flight safety.

  14. Maintenance performance improvement with System Dynamics: A Corrective Maintenance showcase

    NARCIS (Netherlands)

    Deenen, R.E.M.; Van Daalen, C.E.; Koene, E.G.C.

    2008-01-01

    This paper presents a case study of an analysis of a Corrective Maintenance process to realize performance improvement. The Corrective Maintenance process is supported by SAP, which has indicated the performance realisation problem. System Dynamics is used in a Group Model Building process to

  15. A multi-agent based intelligent configuration method for aircraft fleet maintenance personnel

    Directory of Open Access Journals (Sweden)

    Feng Qiang

    2014-04-01

    Full Text Available A multi-agent based fleet maintenance personnel configuration method is proposed to solve the mission oriented aircraft fleet maintenance personnel configuration problem. The maintenance process of an aircraft fleet is analyzed first. In the process each aircraft contains multiple parts, and different parts are repaired by personnel with different majors and levels. The factors and their relationship involved in the process of maintenance are analyzed and discussed. Then the whole maintenance process is described as a 3-layer multi-agent system (MAS model. A communication and reasoning strategy among the agents is put forward. A fleet maintenance personnel configuration algorithm is proposed based on contract net protocol (CNP. Finally, a fleet of 10 aircraft is studied for verification purposes. A mission type with 3 waves of continuous dispatch is imaged. Compared with the traditional methods that can just provide configuration results, the proposed method can provide optimal maintenance strategies as well.

  16. Commercial Aircraft Maintenance Experience Relating to Engine External Hardware

    Science.gov (United States)

    Soditus, Sharon M.

    2006-01-01

    Airlines are extremely sensitive to the amount of dollars spent on maintaining the external engine hardware in the field. Analysis reveals that many problems revolve around a central issue, reliability. Fuel and oil leakage due to seal failure and electrical fault messages due to wire harness failures play a major role in aircraft delays and cancellations (D&C's) and scheduled maintenance. Correcting these items on the line requires a large investment of engineering resources and manpower after the fact. The smartest and most cost effective philosophy is to build the best hardware the first time. The only way to do that is to completely understand and model the operating environment, study the field experience of similar designs and to perform extensive testing.

  17. An analysis of the aircraft engine Component Improvement Program (CIP) : a life cycle cost approach

    OpenAIRE

    Borer, Chris Joseph

    1990-01-01

    Approved for public release; distribution unlimited. Increasing budgetary constraints have prompted actions to reduce the maintenance cost of current naval aircraft. This thesis examines the Aircraft Engine Component Improvement Program (CIP), its impact on these cost at the organizational and intermediate levels of maintenance, and savings from these improvements. The objectives of the research were to identify current life cycle cost (LCC) models used by the Navy andor the other services...

  18. Skills, rules and knowledge in aircraft maintenance: errors in context

    Science.gov (United States)

    Hobbs, Alan; Williamson, Ann

    2002-01-01

    Automatic or skill-based behaviour is generally considered to be less prone to error than behaviour directed by conscious control. However, researchers who have applied Rasmussen's skill-rule-knowledge human error framework to accidents and incidents have sometimes found that skill-based errors appear in significant numbers. It is proposed that this is largely a reflection of the opportunities for error which workplaces present and does not indicate that skill-based behaviour is intrinsically unreliable. In the current study, 99 errors reported by 72 aircraft mechanics were examined in the light of a task analysis based on observations of the work of 25 aircraft mechanics. The task analysis identified the opportunities for error presented at various stages of maintenance work packages and by the job as a whole. Once the frequency of each error type was normalized in terms of the opportunities for error, it became apparent that skill-based performance is more reliable than rule-based performance, which is in turn more reliable than knowledge-based performance. The results reinforce the belief that industrial safety interventions designed to reduce errors would best be directed at those aspects of jobs that involve rule- and knowledge-based performance.

  19. Associations between errors and contributing factors in aircraft maintenance

    Science.gov (United States)

    Hobbs, Alan; Williamson, Ann

    2003-01-01

    In recent years cognitive error models have provided insights into the unsafe acts that lead to many accidents in safety-critical environments. Most models of accident causation are based on the notion that human errors occur in the context of contributing factors. However, there is a lack of published information on possible links between specific errors and contributing factors. A total of 619 safety occurrences involving aircraft maintenance were reported using a self-completed questionnaire. Of these occurrences, 96% were related to the actions of maintenance personnel. The types of errors that were involved, and the contributing factors associated with those actions, were determined. Each type of error was associated with a particular set of contributing factors and with specific occurrence outcomes. Among the associations were links between memory lapses and fatigue and between rule violations and time pressure. Potential applications of this research include assisting with the design of accident prevention strategies, the estimation of human error probabilities, and the monitoring of organizational safety performance.

  20. Optimal Combination of Aircraft Maintenance Tasks by a Novel Simplex Optimization Method

    Directory of Open Access Journals (Sweden)

    Huaiyuan Li

    2015-01-01

    Full Text Available Combining maintenance tasks into work packages is not only necessary for arranging maintenance activities, but also critical for the reduction of maintenance cost. In order to optimize the combination of maintenance tasks by fuzzy C-means clustering algorithm, an improved fuzzy C-means clustering model is introduced in this paper. In order to reduce the dimension, variables representing clustering centers are eliminated in the improved cluster model. So the improved clustering model can be directly solved by the optimization method. To optimize the clustering model, a novel nonlinear simplex optimization method is also proposed in this paper. The novel method searches along all rays emitting from the center to each vertex, and those search directions are rightly n+1 positive basis. The algorithm has both theoretical convergence and good experimental effect. Taking the optimal combination of some maintenance tasks of a certain aircraft as an instance, the novel simplex optimization method and the clustering model both exhibit excellent performance.

  1. Software Maintenance Management Evaluation and Continuous Improvement

    CERN Document Server

    April, Alain

    2008-01-01

    This book explores the domain of software maintenance management and provides road maps for improving software maintenance organizations. It describes full maintenance maturity models organized by levels 1, 2, and 3, which allow for benchmarking and continuous improvement paths. Goals for each key practice area are also provided, and the model presented is fully aligned with the architecture and framework of software development maturity models of CMMI and ISO 15504. It is complete with case studies, figures, tables, and graphs.

  2. Neuropsychological health in F-111 aircraft maintenance workers.

    Science.gov (United States)

    Schofield, Peter W; Gibson, Richard; Tavener, Meredith; Attia, John R; D'Este, Catherine; Guest, Maya; Brown, Anthony M; Lee, Stephen J; Horsley, Keith; Harrex, Warren; Ross, James

    2006-09-01

    To contrast subjective and objective measures of neuropsychological health in F-111 aircraft Deseal/Reseal maintenance personnel, against two appropriate comparison groups. Exposed and comparison participants completed a postal questionnaire which included a validated memory questionnaire and additional questions relating to possible cognitive symptoms. They also underwent a comprehensive neuropsychological assessment and screening for a past or current disturbance of mood. Multiple linear or logistic regression was conducted for each outcome using exposure group and potential confounders as explanatory variables. There was a strong and consistent excess of self-reported cognitive problems among the exposed group relative to the comparison groups including a 2.8-4.3-fold increase in self-reported symptoms of forgetfulness, loss of concentration and difficulty finding the right word. On detailed neuropsychological testing, the exposed group performed significantly worse than comparisons on tests of psychomotor speed, executive functioning, and new learning/memory. These findings could not be accounted for by disturbances of mood or other potential confounders. There was a strong and consistent increase in self-reported cognitive problems among the exposed, and small but significant exposure-specific differences on objective tests of cognitive functioning. The findings are consistent with the development of adverse neuropsychiatric changes related to occupational exposure to solvents.

  3. Cancer incidence and mortality in aircraft maintenance workers.

    Science.gov (United States)

    D'Este, Catherine; Attia, John R; Brown, Anthony M; Gibson, Richard; Gibberd, Robert; Tavener, Meredith; Guest, Maya; Horsley, Keith; Harrex, Warren; Ross, James

    2008-01-01

    A cancer incidence and mortality study was conducted in response to health concerns raised by workers from F-111 aircraft deseal/reseal fuel tank maintenance programs, to determine whether personnel exposed to deseal/reseal had an excess of cancers and mortality. Number of deaths and cancers for individuals involved in F-111 DSRS activities were matched against two Air Force comparison groups. Analyses were weighted to adjust for differences in age, exposure period and rank. Eight hundred seventy-three exposed, 7,577 comparison group one, and 9,408 comparison group two individuals were matched against death and cancer data, with 431 cancers and 431 deaths. Cancer incidence was higher in the exposed group, with marginally significant increases of 40-50% (cancer incidence rate ratio range 1.45-1.62). Exposed group mortality was significantly lower than both comparison groups, likely due to survivor bias in the exposed group (mortality rate ratio range 0.33-0.44). On the balance of probabilities, there is an increased risk of cancer associated with participation in F-111 deseal/reseal activities. 2007 Wiley-Liss, Inc

  4. Sexual function in F-111 maintenance workers: the study of health outcomes in aircraft maintenance personnel.

    Science.gov (United States)

    Brown, Anthony; Gibson, Richard; Tavener, Meredith; Guest, Maya; D'Este, Catherine; Byles, Julie; Attia, John; Horsley, Keith; Harrex, Warren; Ross, James

    2009-06-01

    In Australia, four formal F-111 fuel tank deseal/reseal (DSRS) repair programs were implemented over more than two decades, each involving different processes and using a range of hazardous substances. However, health concerns were raised by a number of workers. The "Study of Health Outcomes in Aircraft Maintenance Personnel" was commissioned by the Australian Department of Defence to investigate potential adverse health outcomes as a result of being involved in the deseal/reseal processes. To compare measures of sexual function in F-111 aircraft fuel tank DSRS maintenance workers, against two appropriate comparison groups. Exposed and comparison participants completed a postal questionnaire which included general questions of health and health behavior, and two specific questions on sexual functioning. They also completed the International Index of Erectile Function (IIEF) questionnaire. Logistic regression was used to explore exposure status and outcome while adjusting for potential confounders. The three outcomes of interest for this study were the proportion of participants with erectile dysfunction (ED) according to the IIEF, the proportion with self-reported loss of interest in sex, and the proportion with self-reported problems with sexual functioning. Compared with each of the comparison groups, a larger proportion of the exposed group reported sexual problems and were classified as having ED according to the IIEF. In logistic regression, the odds of all three outcomes were higher for exposed participants relative to each comparison group and after adjustment for potentially confounding variables including anxiety and depression. There was a consistent problem with sexual functioning in the exposed group that is not explained by anxiety and depression, and it appears related to DSRS activities.

  5. Improving transient analysis technology for aircraft structures

    Science.gov (United States)

    Melosh, R. J.; Chargin, Mladen

    1989-01-01

    Aircraft dynamic analyses are demanding of computer simulation capabilities. The modeling complexities of semi-monocoque construction, irregular geometry, high-performance materials, and high-accuracy analysis are present. At issue are the safety of the passengers and the integrity of the structure for a wide variety of flight-operating and emergency conditions. The technology which supports engineering of aircraft structures using computer simulation is examined. Available computer support is briefly described and improvement of accuracy and efficiency are recommended. Improved accuracy of simulation will lead to a more economical structure. Improved efficiency will result in lowering development time and expense.

  6. Methods to much improve maintenance.

    Science.gov (United States)

    Lam, K C

    2004-11-01

    The benefits to be gained from the application of both value engineering (VE) and quality systems--e.g. quality assurance (QA), and total quality management (TQM)--to the management of building services maintenance have yet to be realised by the building services industry. These concepts are particularly applicable to complex hospital engineering services.

  7. Changes in the mean hearing threshold levels in military aircraft maintenance conscripts.

    Science.gov (United States)

    Park, Won-Ju; Moon, Jai-Dong

    2016-11-01

    Aircraft maintenance crews are constantly exposed to severe aircraft noise. The purpose of this study was to verify whether noise from aircraft adversely affects the hearing threshold levels (HTLs) of aircraft maintenance conscripts during their 2 years of mandatory military service. This study included 3,000 male aircraft maintenance conscripts who work in the military runway area. We measured and analyzed HTLs at 2-4 kHz. The duration of exposure to noise increased with an increase in rank; however, HTLs showed a tendency to decrease. We attributed such contradicting results to the learning effect and adaptation to military service. However, we suspected that sudden deafness in 6 conscripts (0.2%) was due to loud noise in the runway area during military service. The effectiveness of the hearing conservation program for short-term military service personnel could be increased by focusing on preventing sudden deafness and preenlistment baseline audiogram tests.

  8. New principles of periodic aircraft maintenance conditions definition in accordance with aviation safety criteria

    Directory of Open Access Journals (Sweden)

    S. V. Daletskiy

    2015-01-01

    Full Text Available Based on the reliability theory schemes of justifying the volume and structural principles of periodic maintenance (repair of civil aircraft depending on operational conditions meeting the requirements on the failure-free operation, aircraft durability and flight safety are considered.

  9. Multiobjective Optimization of Aircraft Maintenance in Thailand Using Goal Programming: A Decision-Support Model

    Directory of Open Access Journals (Sweden)

    Yuttapong Pleumpirom

    2012-01-01

    Full Text Available The purpose of this paper is to develop the multiobjective optimization model in order to evaluate suppliers for aircraft maintenance tasks, using goal programming. The authors have developed a two-step process. The model will firstly be used as a decision-support tool for managing demand, by using aircraft and flight schedules to evaluate and generate aircraft-maintenance requirements, including spare-part lists. Secondly, they develop a multiobjective optimization model by minimizing cost, minimizing lead time, and maximizing the quality under various constraints in the model. Finally, the model is implemented in the actual airline's case.

  10. A Real-Time Quantitative Condition Alerting and Analysis Support System for Aircraft Maintenance Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Financial constraints and the need for improved operational efficiency are requiring airlines to emphasize "on-condition" maintenance over scheduled maintenance...

  11. Architecture and Key Techniques of Augmented Reality Maintenance Guiding System for Civil Aircrafts

    Science.gov (United States)

    hong, Zhou; Wenhua, Lu

    2017-01-01

    Augmented reality technology is introduced into the maintenance related field for strengthened information in real-world scenarios through integration of virtual assistant maintenance information with real-world scenarios. This can lower the difficulty of maintenance, reduce maintenance errors, and improve the maintenance efficiency and quality of civil aviation crews. Architecture of augmented reality virtual maintenance guiding system is proposed on the basis of introducing the definition of augmented reality and analyzing the characteristics of augmented reality virtual maintenance. Key techniques involved, such as standardization and organization of maintenance data, 3D registration, modeling of maintenance guidance information and virtual maintenance man-machine interaction, are elaborated emphatically, and solutions are given.

  12. 14 CFR 129.14 - Maintenance program and minimum equipment list requirements for U.S.-registered aircraft.

    Science.gov (United States)

    2010-01-01

    ....S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.14 Maintenance program and minimum... maintenance program and approved aircraft minimum equipment list to the FAA office prescribed in paragraph (b... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintenance program and minimum equipment...

  13. 22 CFR 151.11 - Notification of ownership, maintenance or use of vessel and/or aircraft; evidence of insurance.

    Science.gov (United States)

    2010-04-01

    ... AND PERSONNEL § 151.11 Notification of ownership, maintenance or use of vessel and/or aircraft... State in writing of the ownership, maintenance or other regular use of a vessel or aircraft in the... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Notification of ownership, maintenance or use...

  14. 飞机结构性腐蚀和维护%Aircraft Structure Corrosion and Maintenance

    Institute of Scientific and Technical Information of China (English)

    姜福成

    2016-01-01

    在飞机的日常检修和维护过程中,其飞机结构性的腐蚀所造成的问题困扰着日常的航空飞机检修工作。本文通过简述飞机所面对的结构腐蚀问题产生的原因和特点,指出其结构腐蚀对于飞机的发动机、性能等的伤害,并总结日常生活中对飞机结构腐蚀的维护和预防方法。通过探讨这些问题,希望能对航空的机务维修工作带来一些可操作性的建议。%In the daily maintenance and maintenance of the airplane in the process, because of the aircraft structural corrosion caused by problems with daily aviation aircraft maintenance work. Based on aircraft structure corrosion problems facing, through briefly describes the reasons and characteristics, and points out its structure corrosion for aircraft engine, performance such as damage, through these phenomena summarized in daily life for the maintenance of aircraft structure corrosion and prevention method, based on the discussion to these questions, hope to have the aviation maintenance repair work to bring some feasibility Suggestions.

  15. Peripheral Neuropathy in Military Aircraft Maintenance Workers in Australia

    NARCIS (Netherlands)

    Guest, Maya; Attia, John R.; D'Este, Catherine A.; Boggess, May M.; Brown, Anthony M.; Gibson, Richard E.; Tavener, Meredith A.; Ross, James; Gardner, Ian; Harrex, Warren

    Objective: This study aimed to examine possible persisting peripheral neuropathy in a group who undertook fuel tank repairs on F-111 aircraft, relative to two contemporaneous comparison groups. Methods: Vibration perception threshold (VPT) was tested using biothesiometry in 614 exposed personnel,

  16. Aviation Maintenance Technology. Airframe. A204. Aircraft Welding. Instructor Material.

    Science.gov (United States)

    Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This teacher's guide is designed to aid teachers in leading students through a module on aircraft welding on airframes. The module contains four units that cover the following topics: (1) gas welding and cutting; (2) brazing and soldering; (3) shielded metal arc welding; and (4) gas tungsten arc welding. Each unit follows a standardized format…

  17. Improving human performance in maintenance personnel

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Anez, Francisco [Maintenance Training Centre, TECNATOM, S.A, Avd. Montes de Oca, 1. 28709-San Sebastian de los Reyes, Madrid (Spain); Agueero Agueero, Jorge [Technologic Institute, TECNATOM, S.A, Avd. Montes de Oca, 1. 28709-San Sebastian de los Reyes, Madrid (Spain)

    2010-07-01

    The continuous evolution and improvement of safety-related processes has included the analysis, design and development of training plans for the qualification of maintenance nuclear power plant personnel. In this respect, the international references in this area recommend the establishment of systematic qualification programmes for personnel performing functions or carrying out safety related tasks. Maintenance personnel qualification processes have improved significantly, and training plans have been designed and developed based on Systematic Approach to Training methodology to each job position. These improvements have been clearly reflected in recent training programmes with new training material and training facilities focused not only on developing technical knowledge and skills but also on improving attitudes and safety culture. The objectives of maintenance training facilities such as laboratories, mock-ups real an virtual, hydraulic loops, field simulators and other training material to be used in the maintenance training centre are to cover training necessities for initial and continuous qualification. Evidently, all these improvements made in the qualification of plant personnel should be extended to include supplemental personnel (external or contracted) performing safety-related tasks. The supplemental personnel constitute a very spread group, covering the performance of multiple activities entailing different levels of responsibility. Some of these activities are performed permanently at the plant, while others are occasional or sporadic. In order to establish qualification requirements for these supplemental workers, it is recommended to establish a rigorous analysis of job positions and tasks. The objective will be to identify the qualification requirements to assure competence and safety. (authors)

  18. Peripheral neuropathy in military aircraft maintenance workers in Australia.

    Science.gov (United States)

    Guest, Maya; Attia, John R; D'este, Catherine A; Boggess, May M; Brown, Anthony M; Gibson, Richard E; Tavener, Meredith A; Ross, James; Gardner, Ian; Harrex, Warren

    2011-04-01

    This study aimed to examine possible persisting peripheral neuropathy in a group who undertook fuel tank repairs on F-111 aircraft, relative to two contemporaneous comparison groups. Vibration perception threshold (VPT) was tested using biothesiometry in 614 exposed personnel, compared with two unexposed groups (513 technical trades and 403 nontrades). Regression modeling was used to examine associations, adjusting for possible confounders. We observed that 26% of participants had chronic persistent increased VPT in the great toe. In contrast, statistically significant higher VPT of the great toe was observed in the comparison groups; however, the effect was small, about 1/4 the magnitude of diabetes. Age, height, and diabetes were all significant and strong predictors in most models. This study highlights chronic persisting peripheral neuropathy in a population of aircraft maintainers.

  19. The Development and Application of a Value-Driven Aircraft Maintenance Operations Performance Assessment Model combined with Real Options Analysis

    NARCIS (Netherlands)

    Goossens, H.G.; Beelaerts van Blokland, W.W.A.; Curran, R.

    2011-01-01

    This research paper presents the results from the development of an Aircraft Maintenance Operations Performance Assessment Model (AMOPAM). The AMOPAM is able to assess the differences in performance in between two different states or scenarios of aircraft maintenance operations and is able to captur

  20. The Development and Application of a Value-Driven Aircraft Maintenance Operations Performance Assessment Model combined with Real Options Analysis

    NARCIS (Netherlands)

    Goossens, H.G.; Beelaerts van Blokland, W.W.A.; Curran, R.

    2011-01-01

    This research paper presents the results from the development of an Aircraft Maintenance Operations Performance Assessment Model (AMOPAM). The AMOPAM is able to assess the differences in performance in between two different states or scenarios of aircraft maintenance operations and is able to

  1. Maintenance system improvement in cast iron foundry

    Directory of Open Access Journals (Sweden)

    S. Kukla

    2011-07-01

    Full Text Available The work presents the issue of technical equipment management in an iron foundry basing on the assumptions of the TPM system (Total Productive Maintenance. Exploitation analysis of automatic casting lines has been carried out and their work’s influence on the whole production system’s functioning has been researched. Within maintenance system improvement, implementation of autonomic service and planned lines’ review have been proposed in order to minimize the time of breakdown stoppages. The SMED method was used to optimize changeover time, and the OEE (Overall Equipment Effectiveness was applied to evaluate the level of resources usage before and after implementing changes. Further, the influence of the maintenance strategy of casting devices’ efficiency on own costs of casting manufac- ture was estimated.

  2. Impairment of color vision in aircraft maintenance workers

    NARCIS (Netherlands)

    Guest, Maya; D'Este, Catherine; Attia, John; Boggess, May; Brown, Anthony; Tavener, Meredith; Gibson, Richard; Gardner, Ian; Harrex, Warren; Ross, James

    2011-01-01

    Purpose The purpose of the study was to examine possible persisting effects to color vision in a group from the Royal Australian Air Force who had exposure to formulations containing neurotoxins during F-111 fuel tank maintenance, relative to two contemporaneous comparison groups. Methods Color visi

  3. Impairment of color vision in aircraft maintenance workers

    NARCIS (Netherlands)

    Guest, Maya; D'Este, Catherine; Attia, John; Boggess, May; Brown, Anthony; Tavener, Meredith; Gibson, Richard; Gardner, Ian; Harrex, Warren; Ross, James

    2011-01-01

    Purpose The purpose of the study was to examine possible persisting effects to color vision in a group from the Royal Australian Air Force who had exposure to formulations containing neurotoxins during F-111 fuel tank maintenance, relative to two contemporaneous comparison groups. Methods Color

  4. Using Intelligent Simulation to Enhance Human Performance in Aircraft Maintenance

    Science.gov (United States)

    Johnson, William B.; Norton, Jeffrey E.

    1992-01-01

    Human factors research and development investigates the capabilities and limitations of the human within a system. Of the many variables affecting human performance in the aviation maintenance system, training is among the most important. The advent of advanced technology hardware and software has created intelligent training simulations. This paper describes one advanced technology training system under development for the Federal Aviation Administration.

  5. Hearing status among aircraft maintenance personnel in a commercial airline company

    Directory of Open Access Journals (Sweden)

    Greta Smedje

    2011-01-01

    Full Text Available The aim was to study subjective and objective hearing loss in a population of aircraft maintenance workers and identify predictors. A total of 327 aircraft maintenance personnel answered a self-administered work environment questionnaire (response rate 76% and underwent audiometric test. The mean values for the hearing threshold at 3, 4, and 6 kHz for the ear with the most hearing loss were compared with a Swedish population database of persons not occupationally exposed to noise. Equivalent noise exposure during a working day was measured. Relationships between subjective and objective hearing loss and possible predictors (age, years of employment, self-reported exposure to solvents, blood pressure, and psycho-social factors were analyzed by multiple logistic regression. At younger ages (<40 years, aircraft maintenance workers had higher hearing thresholds (1-3 dB compared to the reference group, but such a difference was not found in older employees. Relationships were found between age and objective hearing loss, and between exposure to solvents and reported subjective hearing loss. Equivalent noise exposure during working days were 70-91 dB(A with a maximal noise level of 119 dB(A. Aircraft maintenance workers are exposed to equivalent noise levels above the Swedish occupational standard, including some very high peak exposures. Younger employees have a higher age-matched hearing threshold level compared with a reference group. Thus, there is a need for further preventive measures.

  6. Vocational Training and European Standardisation of Qualifications: The Case of Aircraft Maintenance

    Science.gov (United States)

    Haas, Joachim; Ourtau, Maurice

    2009-01-01

    Initiatives to standardise the conditions for practising certain regulated activities are being taken at European level, particularly in light of the free movement of people and the recognition of qualifications in Member states. This paper looks at the introduction of european licences for aircraft maintenance engineers. It follows an in-depth…

  7. Hearing status among aircraft maintenance personnel in a commercial airline company.

    Science.gov (United States)

    Smedje, Greta; Lunden, Maria; Gärtner, Lotta; Lundgren, Håkan; Lindgren, Torsten

    2011-01-01

    The aim was to study subjective and objective hearing loss in a population of aircraft maintenance workers and identify predictors. A total of 327 aircraft maintenance personnel answered a self-administered work environment questionnaire (response rate 76%) and underwent audiometric test. The mean values for the hearing threshold at 3, 4, and 6 kHz for the ear with the most hearing loss were compared with a Swedish population database of persons not occupationally exposed to noise. Equivalent noise exposure during a working day was measured. Relationships between subjective and objective hearing loss and possible predictors (age, years of employment, self-reported exposure to solvents, blood pressure, and psycho-social factors) were analyzed by multiple logistic regression. At younger ages (aircraft maintenance workers had higher hearing thresholds (1-3 dB) compared to the reference group, but such a difference was not found in older employees. Relationships were found between age and objective hearing loss, and between exposure to solvents and reported subjective hearing loss. Equivalent noise exposure during working days were 70-91 dB(A) with a maximal noise level of 119 dB(A). Aircraft maintenance workers are exposed to equivalent noise levels above the Swedish occupational standard, including some very high peak exposures. Younger employees have a higher age-matched hearing threshold level compared with a reference group. Thus, there is a need for further preventive measures.

  8. Analysis of the Improvement Methods for Equipment Maintenance Support

    Institute of Scientific and Technical Information of China (English)

    ZHANG Rui-chang; ZHAO Song-zheng

    2005-01-01

    According to military requirement, and based on the problems of equipment maintenance support methods in high-tech battles, each element supporting equipment maintenance is analyzed, and the methods for improving equipment maintenance are proposed.

  9. AIRCRAFT MAINTENANCE ENABLED JOINT CONCEPT FOR ENTRY OPERATIONS

    Science.gov (United States)

    2017-04-06

    logistics has been a factor in the use of airpower since its first use back in 1916 when Brigadier General John J. Pershing used aircraft while...Notes 1 Maj Gen Charles Q. Brown Jr., “Untether Operations,” Air and Space Power Journal 29, no. 3 (June 2015): 18. 2 “Air Force Doctrine...2013/09/29/rapid-raptor-package/. 37 Brown Jr., “Untether Operations,” 22. 38 “Air Force Enlisted Classification Directory” (HQ AFPC/DP3ST, October

  10. [Characteristics of a negative effect of aviation noise on hearing organ of aircraft maintenance personnel].

    Science.gov (United States)

    Zinkin, V N; Soldatov, S K; Sheshegov, P M

    2007-01-01

    Otolaryngological examination was carried out of 80 engineers and technicians engaged in maintenance of aircrafts in the airports. They are continuously exposed to occupational aviation noise and therefore are at risk for chronic neurosensory hypoacusis. Pure tone audiogram registers in them a rise in hearing thresholds throughout the whole band of frequencies studied. This means that aviation maintenance staff is exposed to noise containing highly intensive infrasound and high-frequency components. The detected pathology directly correlated with duration of exposure to noise. Development of neurosensory hypoacusis in aviation maintenance specialists starts earlier than in other specialists exposed to noise.

  11. INCREASING THE AIRCRAFT AIRWORTHINESS MAINTENANCE EFICIENCY BASED ON THE PROJECT MANAGEMENT METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Alexander Abramovich Itskovich

    2017-01-01

    Full Text Available The interrelation between aircraft airworthiness maintenance process (AAMP and the process of project man- agement methodology application is demonstrated.A project portfolio can be formed based on the strategic objectives. The projects with the highest priority are car- ried out, including those which strive to improve the efficiency of AAMP. The proposed approach allows to find the priori- ties of specific projects realization, which are included in the airline project portfolio.The project aimed to improve the efficiency of the AAMP of AN-124-100 of "Volga-Dnepr Airlines" is presented as an example. The statistical data analysis of failures of AN-124-100 fleet has demonstrated that wing components most frequently fail, especially spoiler sections, which are subjected to honeycomb skin mass exfoliation and need to be modi- fied. One of the expected project results should be the К1000 reduction of the wing spoilers not less than for 40 % and, respectively, the plane in total - not less than for 4 %.The work is executed in full compliance with the standards of project management. The passport of the project is given, which contains all the necessary information about the project: its goals, outcomes, results, timelines, action plan, budget and participants. A special attention is paid to the risks of the project, their probability assessment and the actions for overcoming possible consequences. It is shown that the implementation of the project "Introduction of aircraft AN-124-100 spoilers technology modi- fication" allows to improve a number of production and technical efficiency indicators, with material, financial and organi- zational resources optimization.

  12. Human Factors Issues In Aircraft Maintenance And Inspection

    Science.gov (United States)

    1990-11-01

    reliability data system ( NPRDS ) " Maintenance personnel performance simulation (MAPPS) * Cognitive environment simulation (CES) * Criteria for equating...System ( NPRDS ) The Nuclear Plant Reliability Data System is a voluntary reporting system sponsored and maintained by the U.S. commercial nuclear power...to 1974. NPRDS data can be recalled by hardware description, vendor, plant, type of failure, source, timeframe, or combinations for use in risk

  13. Aircraft Maintenance Wartime Command and Control: The Might to Fight.

    Science.gov (United States)

    1988-04-01

    Administration from the University of Northern Colorado in 1980. She completed Squadron Officer School in residence in 1981 and is a member of the ACSC...aavantaqes or centraizea ana aecentraiizea decision maKing in wartime tactica! ar:rarz maintenance. Three principies help in this aiscussion: tne decisions...weapons technicians, very few augmentees are neeaea to go to war. The advantages gained from this oecentrai ization rit .ne principie of cohesiveness

  14. Human factors in maintenance: impact on aircraft mishap frequency and severity.

    Science.gov (United States)

    Krulak, David C

    2004-05-01

    Aviation mishaps caused by maintenance factors vary in severity, but can cost untold sums in lives and equipment lost. This study proposes to demonstrate that certain specific maintenance-related human factors are significantly correlated with both mishap frequency and severity. Using information from the Maintenance Error Information Management System (MEIMS), 1,016 aircraft mishaps caused by human factors in maintenance were examined. These mishaps were previously categorized using the Human Factors Analysis and Classification System-Maintenance Extension (HFACS-ME). Frequency analysis was used to determine the most common HFACS-ME factors seen in aircraft mishaps. Logistic regression techniques were used to describe the relationship between the dichotomized outcome of mishap severity and the human factors found in the HFACS-ME. Inadequate supervision, attention/memory errors, and judgment/decision errors were the factors found most often in aircraft mishaps. The factors of inadequate design, inadequate adaptability/flexibility, inadequate lighting/light, confining workspace, and attention/memory error increased odds of being associated with a higher severity mishap. Emphasis in training and education placed in the first three factors mentioned may reduce overall number of mishaps. Concentrating resources on the final five factors may decrease the number of severe mishaps.

  15. A United Allocation Method of Spare Parts and Ground Maintenance Equipment for Civil Aircraft

    Directory of Open Access Journals (Sweden)

    Li Yongkai

    2017-01-01

    Full Text Available Aimed at multi-echelon inventory allocation problem with finite repair capacity for civil aircraft,a united planning method based on queuing theory and Vari-Metric model is presented to deploy the aircraft spare parts and ground maintenance equipment. Through the analysis of actual engineering, the effect of repair time is quantified by the number of maintenance equipment. On this basis, the available of fleet and the cost expense are selected as the objective and constraint respectively, marginal analysis method is set as the optimization, a new allocation scheme which was suit to civil aircraft’s maintenance resources is put forward. By applied examples analysis, it is shows that this method is reasonable and feasible.

  16. Aviation Maintenance (Aircraft Mechanics & Aircraft & Instrument Repair Personnel). Aviation Careers Series. Revised.

    Science.gov (United States)

    Zaharevitz, Walter

    This booklet, one in a series on aviation careers, outlines career opportunities in aviation maintenance. The booklet provides the following information about aviation maintenance jobs: nature of the work, working conditions, where the jobs are, wages and benefits, opportunities for advancement, requirements to enter the job, opportunities for…

  17. Psychosocial indicators among aircraft maintenance workers with and without neck and shoulder musculoskeletal symptoms.

    Science.gov (United States)

    Oliveira, A; Nogueira, H; Diniz, A; Barbieri, D

    2012-01-01

    In the aircraft maintenance industry, most of workers performs manual handling tasks of different materials, varying from small objects up to large pieces of the aircraft. It can increase the occurrence of work-related musculoskeletal disorders (WMSDs), which are strongly associated with high physical demands required by the task. Moreover, psychosocial demands are considered as risk factors for musculoskeletal disorders in both the upper limbs and lumbar spine. Thus, the objective of this study was to assess psychosocial indicators among aircraft maintenance workers according to the presence of neck and shoulder musculoskeletal symptoms. Eighty workers of an aircraft maintenance company were evaluated (32.69 ± 8.25 years, 79.8 ± 13.4 kg, 175 ± 7 cm). According to physical examination, 50 workers were classified as asymptomatic (AS - 4.1 ± 3.17 positive signs) whilst 30 workers were classified as symptomatic (SS - 26.72 ± 11.44 positive signs). AS and SS have shown similar profile of demand (p = 0.62), control (p = 0.66) and social support (p = 0.74) according to the Job Content Questionnaire. However, the groups are different when considering work engagement variables. In general, SS have higher scores than AS (p < 0.05).

  18. Impairment of color vision in aircraft maintenance workers.

    Science.gov (United States)

    Guest, Maya; D'Este, Catherine; Attia, John; Boggess, May; Brown, Anthony; Tavener, Meredith; Gibson, Richard; Gardner, Ian; Harrex, Warren; Ross, James

    2011-10-01

    The purpose of the study was to examine possible persisting effects to color vision in a group from the Royal Australian Air Force who had exposure to formulations containing neurotoxins during F-111 fuel tank maintenance, relative to two contemporaneous comparison groups. Color vision was tested in 512 exposed personnel, 458 technical-trade comparisons, and 330 non-technical comparisons using the Ishihara test plates and the Lanthony D-15 Desaturated Color disk arrangement test. Participants were excluded if they failed the Ishihara test as this indicates congenital color blindness. From the Lanthony results, the type of color deficient vision (CDV) was diagnosed, and additionally, the Bowman's color confusion index (CCI) was calculated. Regression models were used to examine whether there was an association between color vision deficiencies and F-111 fuel tank maintenance, adjusting for possible confounders. The CCI ranged from 1 to 2.8 (median 1.2, quartiles 1.1, 1.4) in the 2,600 eyes tested. Forty five percent of all participants had blue-yellow CDV in at least one eye. Deficiencies of this nature are caused by environmental exposures. Logistic regression demonstrated statistically significant differences in CCI category in the exposed group versus technical group (odds ratio 1.7: 95% CI 1.3-2.0) and a blue-yellow confusion in the exposed group versus technical group (odds ratio 1.4: 95% CI 1.1-1.7). No differences were observed between the exposed group and the non-technical group. The results indicate reduced color discrimination among the exposed subjects compared to one of two control groups. The findings may be due to previous exposure to solvents among the air force personnel.

  19. Standard Practice for Total Immersion Corrosion Test for Aircraft Maintenance Chemicals

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This practice covers the determination of the corrosiveness of aircraft maintenance chemicals on aircraft metals with time under conditions of total immersion by a combination of weight change measurements and visual qualitative determination of change. 1.2 The values stated in SI units are to be regarded as standard. The values in parentheses are for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  20. Research on Zonal Inspection Intervals of Civil Aircraft Based on Improved FAHP

    Directory of Open Access Journals (Sweden)

    Lu Xiang

    2013-07-01

    Full Text Available One of the most important things in formulating aircraft maintenance program is to determine the zonal inspection intervals. In accordance with the current situation that there has no perfect rating systems of zonal inspection under MSG-3 (Maintenance Steering Group-3 analysis system, a method to calculate the integrate level of zonal rating is to analyze the impact of aircraft zonal rating factors, establish a hierarchical index evaluation system and then utilize the improved fuzzy analytic hierarchy process (FAHP to determine the indexes’ weight. Moreover, the zonal inspection intervals can be established according to the correspondence between rates and intervals. Finally, take a typical zone of an aircraft as an example to verify the method.  

  1. A Real-Time Quantitative Condition Alerting and Analysis Support System for Aircraft Maintenance Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Financial constraints, government recommendations, and the need for improved operational efficiency are requiring airlines to review their "on-condition" maintenance...

  2. Standard Practice for Corrosion of Aircraft Metals by Total Immersion in Maintenance Chemicals

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This practice covers the determination of the corrosiveness of tank-type aircraft maintenance chemicals on aircraft metals and the corrodibility of metals in these maintenance chemicals with time. The determination is made under conditions of total immersion by a combination of weight change measurements and visual qualitative determinations of change. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific precautions, see Section 6.

  3. A Survey of the Aircraft Maintenance Industry to Solicit Perceptions Regarding the Effectiveness of Recent Graduates of F.A.A. Approved Maintenance Schools.

    Science.gov (United States)

    O'Brian, Benjamin H.

    A study examined the perceptions of employers in the aircraft maintenance industry regarding the effectiveness of recent graduates of Federal Aeronautics Administration (FAA)-approved maintenance schools. Of the 100 employers who were contacted, 68 returned usable surveys. Based on responses, it was concluded that the views of employers in the…

  4. A Survey of the Aircraft Maintenance Industry to Solicit Perceptions Regarding the Effectiveness of Recent Graduates of F.A.A. Approved Maintenance Schools.

    Science.gov (United States)

    O'Brian, Benjamin H.

    A study examined the perceptions of employers in the aircraft maintenance industry regarding the effectiveness of recent graduates of Federal Aeronautics Administration (FAA)-approved maintenance schools. Of the 100 employers who were contacted, 68 returned usable surveys. Based on responses, it was concluded that the views of employers in the…

  5. Exposure to fall hazards and safety climate in the aircraft maintenance industry.

    Science.gov (United States)

    Neitzel, Richard L; Seixas, Noah S; Harris, Michael J; Camp, Janice

    2008-01-01

    Falls represent a significant occupational hazard, particularly in industries with dynamic work environments. This paper describes rates of noncompliance with fall hazard prevention requirements, perceived safety climate and worker knowledge and beliefs, and the association between fall exposure and safety climate measures in commercial aircraft maintenance activities. Walkthrough observations were conducted on aircraft mechanics at two participating facilities (Sites A and B) to ascertain the degree of noncompliance. Mechanics at each site completed questionnaires concerning fall hazard knowledge, personal safety beliefs, and safety climate. Questionnaire results were summarized into safety climate and belief scores by workgroup and site. Noncompliance rates observed during walkthroughs were compared to the climate-belief scores, and were expected to be inversely associated. Important differences were seen in fall safety performance between the sites. The study provided a characterization of aircraft maintenance fall hazards, and also demonstrated the effectiveness of an objective hazard assessment methodology. Noncompliance varied by height, equipment used, location of work on the aircraft, shift, and by safety system. Although the expected relationship between safety climate and noncompliance was seen for site-average climate scores, workgroups with higher safety climate scores had greater observed noncompliance within Site A. Overall, use of engineered safety systems had a significant impact on working safely, while safety beliefs and climate also contributed, though inconsistently. The results of this study indicate that safety systems are very important in reducing noncompliance with fall protection requirements in aircraft maintenance facilities. Site-level fall safety compliance was found to be related to safety climate, although an unexpected relationship between compliance and safety climate was seen at the workgroup level within site. Finally, observed

  6. Depression Prevalence and Exposure to Organophosphate Esters in Aircraft Maintenance Workers.

    Science.gov (United States)

    Hardos, Jennifer E; Whitehead, Lawrence W; Han, Inkyu; Ott, Darrin K; Waller, D Kim

    2016-08-01

    Previous studies found that aircraft maintenance workers may be exposed to organophosphates in hydraulic fluid and engine oil. Studies have also illustrated a link between long-term low-level organophosphate pesticide exposure and depression. A questionnaire containing the Patient Health Questionnaire 8 depression screener was e-mailed to 52,080 aircraft maintenance workers (with N = 4801 complete responses) in a cross-sectional study to determine prevalence and severity of depression and descriptions of their occupational exposures. There was no significant difference between reported depression prevalence and severity in similar exposure groups in which aircraft maintenance workers were exposed or may have been exposed to organophosphate esters compared to similar exposure groups in which they were not exposed. However, a dichotomous measure of the prevalence of depression was significantly associated with self-reported exposure levels from low (OR: 1.21) to moderate (OR: 1.68) to high exposure (OR: 2.70) and with each exposure route including contact (OR: 1.68), inhalation (OR: 2.52), and ingestion (OR: 2.55). A self-reported four-level measure of depression severity was also associated with a self-reported four-level measure of exposure. Based on self-reported exposures and outcomes, an association is observed between organophosphate exposure and depression; however, we cannot assume that the associations we observed are causal because some workers may have been more likely to report exposure to organophosphate esters and also more likely to report depression. Future studies should consider using a larger sample size, better methods for characterizing crew chief exposures, and bioassays to measure dose rather than exposure. Hardos JE, Whitehead LW, Han I, Ott DK, Waller DK. Depression prevalence and exposure to organophosphate esters in aircraft maintenance workers. Aerosp Med Hum Perform. 2016; 87(8):712-717.

  7. Maintenance-free lead acid battery for inertial navigation systems aircraft

    Science.gov (United States)

    Johnson, William R.; Vutetakis, David G.

    1995-05-01

    Historically, Aircraft Inertial Navigation System (INS) Batteries have utilized vented nickel-cadmium batteries for emergency DC power. The United States Navy and Air Force developed separate systems during their respective INS developments. The Navy contracted with Litton Industries to produce the LTN-72 and Air Force contracted with Delco to produce the Carousel IV INS for the large cargo and specialty aircraft applications. Over the years, a total of eight different battery national stock numbers (NSNs) have entered the stock system along with 75 battery spare part NSNs. The Standard Hardware Acquisition and Reliability Program is working with the Aircraft Battery Group at Naval Surface Warfare Center Crane Division, Naval Air Systems Command (AIR 536), Wright Laboratory, Battelle Memorial Institute, and Concorde Battery Corporation to produce a standard INS battery. This paper discusses the approach taken to determine whether the battery should be replaced and to select the replacement chemistry. The paper also discusses the battery requirements, aircraft that the battery is compatible with, and status of Navy flight evaluation. Projected savings in avoided maintenance in Navy and Air Force INS Systems is projected to be $14.7 million per year with a manpower reduction of 153 maintenance personnel. The new INS battery is compatible with commercially sold INS systems which represents 66 percent of the systems sold.

  8. The potential risk of communication media in conveying critical information in the aircraft maintenance organisation: a case study

    Science.gov (United States)

    Shukri, S. Ahmad; Millar, R. M.; Gratton, G.; Garner, M.

    2016-10-01

    In the world of aircraft maintenance organisation, verbal and written communication plays a pivotal role in transferring critical information in relation to aircraft safety and efficiency. The communication media used to convey the critical information between departments at an aircraft maintenance organisation have potential risk in misunderstanding of the information. In this study, technical and non-technical personnel from five different departments at an aircraft maintenance organisation were interviewed on the communication media they normally utilised to communicate six different work procedures that are closely related to aircraft safety and efficiency. This is to discover which communication media pose higher risk in misunderstanding critical information. The findings reveal that written communication pose higher risk of misinterpretation compared with verbal communication when conveying critical information between departments.

  9. Blood lead level and types of aviation fuel in aircraft maintenance crew.

    Science.gov (United States)

    Park, Won-Ju; Gu, Hye-Min; Lee, Suk-Ho

    2013-10-01

    This study inquired into any significant difference in blood lead levels (BLLs) among aircraft maintenance crews at the air-bases, each with a different aviation fuel in use, and confirmed an environmental impact of leaded aviation gasoline (AVGAS). This study included a total of 256 male aircraft maintenance personnel, among whom 105 used only AVGAS as their aviation fuel, while 151 used only jet propellant 8 (JP-8), a kerosene variety. BLLs were measured and the data on related factors were obtained. The arithmetic and geometric means of BLLs of the personnel at the airbases that used only AVGAS were 4.20 microg x dl(-1) and 4.01 microg x dl(-1) and that used only JP-8 were 3.79 microg x dl(-1) and 3.57 microg x dl(-1), respectively. The BLLs of the maintenance crew of the main workspace that was located within a 200-m distance from the runway were higher than those of the main workspace that was located 200 m or farther from the runway. The longer the work hours in the runway or the longer the work duration, the higher the BLLs of the maintenance crew. This investigation exposed the fact that a body's BLL could be increased by AVGAS emissions through the examination of aircraft maintenance crew. This result is in agreement with results of previous studies that suggest proximity to an airport may be associated with elevated BLLs for adults and children. Collectively, the results of the current study and previous research suggest that long-duration inhabitation and/or activities in close proximity to an air facility should be limited given that lead poses known health risks.

  10. Advanced Acoustic Blankets for Improved Aircraft Interior Noise Reduction Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this project advanced acoustic blankets for improved low frequency interior noise control in aircraft will be developed and demonstrated. The improved performance...

  11. The passing of the shift in aircraft maintenance--a task that produces deaths.

    Science.gov (United States)

    Campos, Reginaldo; Martins, Edgard; Soares, Marcelo

    2012-01-01

    Maintenance tasks, especially in heavy maintenance, may not be completed in a single shift. Aircraft maintenance technicians often take work in progress by colleagues, and spend the incomplete work for a change of team. The need for accuracy and efficiency of information transfer in many cases, without having time to have a meeting to pass the service is a crucial aspect of maintenance work. The ideal shift change can occur normally before delivery and continues to proceed normally after delivery. Although a shift change create challenges for communication, they also offer opportunities to detect and correct errors, where the task of delivery is an opportunity to identify the problem and fix it. In this case, the task was done correctly the first round, however, a problem began when the second round took. One example is a case in which the first round have removed a defective part for replacement and let the component of aircraft at end of turn with problems. Instead of ordering and installation of an operational component, the second round was then reinstall the faulty component, not realizing he had information about the problem attached.

  12. The passing of the shift in aircraft maintenance - a task that produces deaths.

    Science.gov (United States)

    Campos, Reginaldo; Martins, Edgard; Soares, Marcelo M

    2012-01-01

    Maintenance tasks, especially in heavy maintenance, may not be completed in a single shift. Aircraft maintenance technicians often take work in progress by colleagues, and spend the incomplete work for a change of team. The need for accuracy and efficiency of information transfer in many cases, without having time to have a meeting to pass the service is a crucial aspect of maintenance work. The ideal shift change can occur normally before delivery and continues to proceed normally after delivery. Although a shift change create challenges for communication, they also offer opportunities to detect and correct errors, where the task of delivery is an opportunity to identify the problem and fix it. In this case, the task was done correctly the first round, however, a problem began when the second round took. One example is a case in which the first round have removed a defective part for replacement and let the component of aircraft at end of turn with problems. Instead of ordering and installation of an operational component, the second round was then reinstall the faulty component, not realizing he had information about the problem attached.

  13. A Reliability-Based Approach to Nonrepairable Spare Part Forecasting in Aircraft Maintenance System

    Directory of Open Access Journals (Sweden)

    Nataša Z. Kontrec

    2015-01-01

    Full Text Available In recent times, spare parts inventory systems have been extensively researched, but most inventory models were not fully adequate due to the stochastic nature of inventory environment. This paper proposes an approach that supports decision making process in planning and controlling of spare parts in aircraft maintenance systems. Reliability characteristics of aircraft consumable parts were analyzed in order to substantiate this approach. Moreover, the proposed reliability model was used to evaluate characteristics of subassemblies and/or assemblies these parts belong to. Finally, an innovative approach for determining the total amount of parts required in inventory and underage costs, based on observing the total unit time as a stochastic process, is presented herein.

  14. Improving Diagnostics Capabilities Through Enhanced Maintenance Data Collection

    Science.gov (United States)

    1990-12-01

    7100 11. SUPPLEMENTARY NOTES 12a. DISTRIBUTION/ AVAILABILTY STATEMENT 12b. DISTRIBUTION CODE Approved for public release, unlimited distribution. 2A 13...Service MDC systems are designed to collect information for maintenance management activities and to provide hardware usage information for the supply...General Motors Computerized Automotive Maintenance System demonstrated 33% improvement in maintenance shop pro- ductivity within 3 weeks of usage , (2

  15. Advanced Acoustic Blankets for Improved Aircraft Interior Noise Reduction Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the proposed Phase II research effort is to develop heterogeneous (HG) blankets for improved sound reduction in aircraft structures. Phase I...

  16. The adaptation of sustainable biojet fuels and its effect on aircraft engine maintenance

    Science.gov (United States)

    Mohd Noh, H.; Rodrigo, G. A.; Rahman, N. A. Abdul

    2016-10-01

    Aviation industries are looking into several resources for renewable and sustainable energy. Among those attention is focused in biojet fuel. This paper engages the issue of biojet fuel emissions that increase the environmental concern in the air transport sector. The paper presents the use of biojet fuel and its effect on aircraft engine maintenance through preliminary data collections, and a review of its development process in operations for time and goal. As conclusion, airlines management needs to adapt and adopt the transition to alternative fuels, especially given the global biofuel trend emerging due to the authority approval.

  17. An improved source model for aircraft interior noise studies

    Science.gov (United States)

    Mahan, J. R.; Fuller, C. R.

    1985-01-01

    There is concern that advanced turboprop engines currently being developed may produce excessive aircraft cabin noise level. This concern has stimulated renewed interest in developing aircraft interior noise reduction methods that do not significnatly increase take off weight. An existing analytical model for noise transmission into aircraft cabins was utilized to investigate the behavior of an improved propeller source model for use in aircraft interior noise studies. The new source model, a virtually rotating dipole, is shown to adequately match measured fuselage sound pressure distributions, including the correct phase relationships, for published data. The virtually rotating dipole is used to study the sensitivity of synchrophasing effectiveness to the fuselage sound pressure trace velocity distribution. Results of calculations are presented which reveal the importance of correctly modeling the surface pressure phase relations in synchrophasing and other aircraft interior noise studies.

  18. Statistical estimation of service cracks and maintenance cost for aircraft structures

    Science.gov (United States)

    Yang, J.-N.

    1975-01-01

    A method is developed for the statistical estimation of the number of cracks to be repaired in service as well as the repair and the maintenance costs. The present approach accounts for the statistical distribution of the initial crack size, the statistical nature of the NDI technique used for detecting the crack, and the renewal process for the crack propagation of repaired cracks. The mean and the standard deviation of the cumulative number of cracks to be repaired are computed as a function of service time. The statistics of the costs of repair and maintenance, expressed in terms of the percentage of the cost of replacement, are estimated as a function of service time. The results of the present study provide relevant information for the decision of fleet management, the estimation of life cycle cost, and procurement specifications. The present study is essential to the design and cost optimization of aircraft structures.

  19. Exposure of aircraft maintenance technicians to organophosphates from hydraulic fluids and turbine oils: a pilot study.

    Science.gov (United States)

    Schindler, Birgit Karin; Koslitz, Stephan; Weiss, Tobias; Broding, Horst Christoph; Brüning, Thomas; Bünger, Jürgen

    2014-01-01

    Hydraulic fluids and turbine oils contain organophosphates like tricresyl phosphate isomers, triphenyl phosphate and tributyl phosphate from very small up to high percentages. The aim of this pilot study was to determine if aircraft maintenance technicians are exposed to relevant amounts of organophosphates. Dialkyl and diaryl phosphate metabolites of seven organophosphates were quantified in pre- and post-shift spot urine samples of technicians (N=5) by GC-MS/MS after solid phase extraction and derivatization. Pre- and post shift values of tributyl phosphate metabolites (dibutyl phosphate (DBP): median pre-shift: 12.5 μg/L, post-shift: 23.5 μg/L) and triphenyl phosphate metabolites (diphenyl phosphate (DPP): median pre-shift: 2.9 μg/L, post-shift: 3.5 μg/L) were statistically higher than in a control group from the general population (median DBP: aircraft maintenance technicians were occupationally exposed to tributyl and triphenyl phosphate but not to tricresyl phosphate, tri-(2-chloroethyl)- and tri-(2-chloropropyl)-phosphate. Further studies are necessary to collect information on sources, routes of uptake and varying exposures during different work tasks, evaluate possible health effects and to set up appropriate protective measures. Copyright © 2013 Elsevier GmbH. All rights reserved.

  20. Musculoskeletal disorders and psychosocial risk factors among workers of the aircraft maintenance industry.

    Science.gov (United States)

    Nogueira, Helen Cristina; Diniz, Ana Carolina Parise; Barbieri, Dechristian França; Padula, Rosimeire Simprini; Carregaro, Rodrigo Luiz; de Oliveira, Ana Beatriz

    2012-01-01

    During the recent decades Brazil has experienced an exponential growth in the aviation sector resulting in an increasing workforce. The aircraft maintenance industry stands out, where the workers have to handle different kind of objects. The aim of this study was to evaluate psychosocial indicators as well as musculoskeletal symptoms and disorders among aircraft maintenance workers. One hundred and one employees were evaluated (32.69 ± 8.25 yr, 79.8 ± 13.4 kg, and 1.75 ± 0.07 m). Musculoskeletal symptoms and disorders were assessed through the Nordic Musculoskeletal Questionnaire (NMQ) and a standardized physical examination. The Job Content Questionnaire (JCQ) and the Utrecht Work Engagement Scale (UWES) were applied to evaluate psychosocial indicators. Results of the NMQ indicate the lower back as the most affected body region. On the other hand, the physical examination has shown clinical diagnosis of shoulder disorders. Neck, upper back and ankle/foot were also reported as painful sites. Most of workers have active work-demand profile and high work engagement levels. We suggest that musculoskeletal symptoms may be related to high biomechanical demand of the tasks performed by workers, what must be further investigated.

  1. An estimation method for direct maintenance cost of aircraft components based on particle swarm optimization with immunity algorithm

    Institute of Scientific and Technical Information of China (English)

    WU Jing-min; ZUO Hong-fu; CHEN Yong

    2005-01-01

    A particle swarm optimization (PSO) algorithm improved by immunity algorithm (IA) was presented.Memory and self-regulation mechanisms of IA were used to avoid PSO plunging into local optima. Vaccination and immune selection mechanisms were used to prevent the undulate phenomenon during the evolutionary process. The algorithm was introduced through an application in the direct maintenance cost (DMC) estimation of aircraft components. Experiments results show that the algorithm can compute simply and run quickly. It resolves the combinatorial optimization problem of component DMC estimation with simple and available parameters. And it has higher accuracy than individual methods, such as PLS, BP and v-SVM, and also has better performance than other combined methods, such as basic PSO and BP neural network.

  2. Maintenance problems associated with the operation of the F402 /Pegasus/ engine in the AV-8A /Harrier/ aircraft

    Science.gov (United States)

    Stanley, C. W.; Hood, W. E.

    1981-01-01

    The U.S. Marine Corp (USMC) has been operating the only V/STOL attack aircraft in the western world since 1971. Some of the maintenance problems experienced are related to the unique V/STOL design criteria of the Pegasus engine. However, the major part of the required maintenance effort is found to involve the more conventional engine problems. A description of the aircraft engine is provided and the problems resulting from V/STOL design demands are examined. Attention is given to the fuel system control, the engine air bleed, foreign object damage to the hp compressor, and the engine exhaust system.

  3. Reliability Centered Maintenance in Schedule Improvement of Automotive Assembly Industry

    Directory of Open Access Journals (Sweden)

    Rizauddin Ramli

    2012-01-01

    Full Text Available Problem statement: Today, in many automotive manufacturing companies, maintenance management is an important factor to maintain the plant operation and production equipments. Approach: In this study, we present an implementation of Reliability Centered Maintenance (RCM practice in one of the automotive manufacturing company in Malaysia. The RCM practice was used to assist the company in focusing their maintenance activities based on the criticalities of the equipments by applying the Failure Modes and Effects Analysis (FMEA. The implementation of RCM was carried out in 4 stages; preparation, system analysis, decision making and feedback. The aim of RCM was to reduce the number of maintenance checklist and to improve significantly the integrity of maintenance practice. Results: As a result, the new RCM framework was generated where Class A equipment was at the top of the monthly maintenance frequency priority, followed by Class B and Class C equipment which had lesser critical value. Conclusion: The new RCM framework is used to conduct visible guideline and propose a new maintenance schedule. The guideline is useful for future maintenance strategy improvement. After the implementation, it can be ascertained that our proposed RCM is useful in reducing maintenance personnel burden and this leads to improvement of productivity.

  4. An observed relationship between vestibular function and auditory thresholds in aircraft-maintenance workers.

    Science.gov (United States)

    Guest, Maya; Boggess, May; D'Este, Catherine; Attia, John; Brown, Anthony

    2011-02-01

    We sought to examine the vestibular function and whether an association exists between vestibular function and hearing thresholds in a group of military aircraft-maintenance workers with exposures to high levels of noise and organic solvents, relative to two different comparison groups. Vestibular function (using functional reach) and hearing (with pure-tone audiometry) were assessed in 601 exposed personnel, compared with two unexposed groups (500 technical trade and 391 nontrade). Linear regression model showed that functional reach was slightly better for the comparison groups than the exposed group, with only one group being statistically significant, and there was a significant association between vestibular function and auditory thresholds at 500 and 1000 Hz. This study has demonstrated a relationship between low-frequency hearing loss, vestibular dysfunction, anxiety, and depression in an occupational population.

  5. The Activity Based Costing method opportunity to assess and master the aircraft maintenance service cost for Third Party: A Case Study

    Directory of Open Access Journals (Sweden)

    Driss Rchid

    2013-01-01

    Full Text Available This work illustrates how to calculate accurate aircraft maintenance costs using Activity Based Costing (ABC. Comparing to traditional cost calculation, the proposed method is useful for aircrafts maintenance activity integrated to Airline Company and who wants to diversify its revenue by selling some available maintenance slots to third party clients for a competitive price. This paper takes base maintenance check process of a Moroccan airline aircrafts maintenance activity as a case study. The actual method used to calculate aircraft maintenance check cost cant not be applied to third party client pricing system. The ABC method shows substantial benefits if it is successfully implemented. Data collection through interviews and questionnaires are the main sources to this study.

  6. An Improved Logic Diagram of RCM with the Proactive Maintenance

    Institute of Scientific and Technical Information of China (English)

    SONG Wenyuan; KANG Jianshe; WEN Liang; HONG Qing

    2006-01-01

    For some repeatedly occurring failure with root cause, the reliability centered maintenance (RCM) can't deal with them effectively. So, the logic diagram of RCM was improved by combining it with proactive maintenance technology. First, root cause analysis is used to build a key result-cause chain of the repeatedly occur failure. Then, a reasonable link in the chain, which work station is suitable to be monitored and repaired, should be selected. Finally, the corresponding proactive maintenance measure should be adopted to prevent the matter occur on the chain and broken the key result-cause chain, and the repeatedly occur failure is to be prevent at a deeper level or from the root cause. By doing this, a system engineering method comes into being, not only it can determine the needs of preventive maintenance for equipment, but also determine the proactive maintenance needs for equipment. The analysis result of reliability centered maintenance and the analysis result considering proactive maintenance are combined to form a maintenance guideline containing proactive maintenance strategy.

  7. Evaluation of an improved air distribution system for aircraft cabin

    DEFF Research Database (Denmark)

    Pang, Liping; Xu, Jie; Fang, Lei

    2013-01-01

    An improved air distribution system for aircraft cabin was proposed in this paper. Personalized outlets were introduced and placed at the bottom of the baggage hold. Its ratio of fresh air to recirculation air and the conditioned temperature of different types of inlets were also designed carefully...

  8. METHOD IMPROVEMENT FOR DETERMINING THE TECHNICAL LEVEL OF CIVIL AIRCRAFT

    Directory of Open Access Journals (Sweden)

    2016-01-01

    Full Text Available Aircraft are high-tech engineering products which are characterized by a wide range of properties including the two most important groups that respectively characterize the efficiency and technical level.Improving the aircraft efficiency is an essential factor for air transport development, but the efficiency can not be fully describe the technical system, especially in forecasting and new technology requirements development. Aircraft de- signer must evaluate the prospects of a technical solution, but it’s not always possible to calculate the efficiency accuratelyat the design stage. The operator should be able to choose the most technically-advanced aircraft available in the market inorder not to let it grow obsolete quickly. This determines the need for non-economic evaluation of technical systems that can be done by assessment of their technical level.The technical level is a general index that includes a set of technical perfection indicators. Technical perfection is reflected in terms of material and energy intensity, in terms of ergonomics, safety, etc. and is achieved as a result of origi- nal design solutions, the use of new high-strength low-density materials, the introduction of advanced technological pro-cesses, calculation methods, verification, testing, etc.There is a tight connection between the product properties and its weight, because weight is the material reflection of these properties. Therefore, improvement of the product properties usually leads to an intense increase of its weight. To deal with this phenomenon is only possible with widely using scientific and technical progress results. In accordance with this, the technical perfection can be interpreted as a major component of quality that is created without the weight increase. This approach requires investment in research and testing new technical solutions.The method was developed to determine the technical level of civil long-haul aircraft which has been modified to

  9. A maintenance model for k-out-of-n subsystems aboard a fleet of advanced commercial aircraft

    Science.gov (United States)

    Miller, D. R.

    1978-01-01

    Proposed highly reliable fault-tolerant reconfigurable digital control systems for a future generation of commercial aircraft consist of several k-out-of-n subsystems. Each of these flight-critical subsystems will consist of n identical components, k of which must be functioning properly in order for the aircraft to be dispatched. Failed components are recoverable; they are repaired in a shop. Spares are inventoried at a main base where they may be substituted for failed components on planes during layovers. Penalties are assessed when failure of a k-out-of-n subsystem causes a dispatch cancellation or delay. A maintenance model for a fleet of aircraft with such control systems is presented. The goals are to demonstrate economic feasibility and to optimize.

  10. Depot Maintenance: Improved Strategic Planning Needed to Ensure That Army and Marine Corps Depots Can Meet Future Maintenance Requirements

    Science.gov (United States)

    2009-09-01

    of Representatives DEPOT MAINTENANCE Improved Strategic Planning Needed to Ensure That Army and Marine Corps Depots Can Meet Future...Depot Maintenance. Improved Strategic Planning Needed to Ensure That Army and Marine Corps Depots Can Meet Future Maintenance Requirements 5a... Strategic Planning Needed to Ensure That Army and Marine Corps Depots Can Meet Future Maintenance Requirements Highlights of GAO-09-865, a report to

  11. AUTOMOTIVE MAINTENANCE PLAN IMPROVEMENT BASED ON DISTRIBUTION OF FAILURE TIMES

    Directory of Open Access Journals (Sweden)

    Alexandru BOROIU

    2016-05-01

    Full Text Available In accordance with the concept of "RCM - Reliability Centered Maintenance", the paper presents a study on the possibility to improve maintenance plan for the most frequently replaced parts from a sample of cars, followed during the operation period: front/rear brake pads. After analyzing the reliability of these components, it is found that there is the possibility of introducing the obligatory replacement operation of brake pads who have reached the third technical inspection without being replaced, sacrificing resource exploitation of them, but improving the benefits for the client - the automotive availability.

  12. TRIZ method application for improving the special vehicles maintenance

    Directory of Open Access Journals (Sweden)

    Petrović Saša

    2014-01-01

    Full Text Available TRIZ methodology provides an opportunity for improving the classical engineering approach based on personal knowledge and experience. This paper presents the application of TRIZ methods for improving vehicle maintenance where special equipment is installed. A specific problem is the maintenance of the periscopes with heating system. Protective glass panels with heating system are rectangular glass elements. Their purpose is to perform mechanical protection of built-in prisms and provide heating of the prisms. Aging and long-term use leads to failure of these elements. The practice requires solutions in order to extend the lifetime of the system. New solution is evaluated by simulation and experiment.

  13. Genotoxic changes after low-level solvent and fuel exposure on aircraft maintenance personnel.

    Science.gov (United States)

    Lemasters, G K; Livingston, G K; Lockey, J E; Olsen, D M; Shukla, R; New, G; Selevan, S G; Yiin, J H

    1997-07-01

    Individuals may be exposed to solvent mixtures and fuel either at work or home, through air, water and food contamination. Few studies have addressed the genotoxic effects of mixed, low-level exposure to fuel and solvent. This was an optimally designed study where each subject was sampled prior to exposure and after 15 and 30 weeks while exposed, in a repeated measures design with each subject serving as his own control. Fifty men aged between 18 and 50, working on aircraft equipment operation and maintenance at a military installation were included. Eight unexposed men were concurrently sampled. Sister-chromatid exchanges (SCE) and micronuclei (MN) frequency were measured in conjunction with air sampling and expired breath analysis for jet fuel (JP-4), 1,1,1-trichloroethane, methyl ethyl ketone, xylenes, toluene and methylene chloride. Exposure levels measured by industrial hygiene were very low (all means <6 p.p.m.), <10% of the OSHA standard. Expired breath levels were also low, <25 p.p.b. A small but statistically significant increase in the frequency of SCE occurred after 30 weeks of exposure for sheet metal workers (P = 0.003) and for painters (P = 0.05). The MN frequency in the sheet metal workers initially showed a statistically significant increase, but by 30 weeks had decreased. Cigarette smoking, alcohol and caffeine use were not associated with changes from baseline for either MN or SCE. Smokers, however, had significantly higher values of SCEs at baseline than did nonsmokers. In summary, these findings suggest that small increases in SCEs in particular, may serve as a sensitive biologic indicator of low level hydrocarbon exposure in as much as statistically significant changes occurred in the highest exposed groups but not in the low or no exposure groups. Chance occurrence or exposures to other occupational or non-occupational agents cannot be eliminated as a cause of the study findings.

  14. Standard Test Method to Determine Color Change and Staining Caused by Aircraft Maintenance Chemicals upon Aircraft Cabin Interior Hard Surfaces

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2001-01-01

    1.1 This test method covers the determination of color change and staining from liquid solutions, such as cleaning or disinfecting chemicals or both, on painted metallic surfaces and nonmetallic surfaces of materials being used inside the aircraft cabin. The effects upon the exposed specimens are measured with the AATCC Gray Scale for Color Change and AATCC Gray Color Scale for Staining. Note 1—This test method is applicable to any colored nonmetallic hard surface in contact with liquids. The selected test specimens are chosen because these materials are present in the majority of aircraft cabin interiors. 1.2This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  15. IMPROVEMENT DIRECTIONS OF MAINTENANCE SYSTEM OF MULTIPLE UNIT

    Directory of Open Access Journals (Sweden)

    O. S. Krasheninin

    2014-07-01

    Full Text Available Purpose. Efficiency of function multiple units park (MUP as a complex system considerably depends on the modes and conditions of its operation, which is defined as the state of their eigenstate and state of the system content. The purpose is the decision scientifically - a technical problem of system of the content of maintenance operation and repair of a rolling stock. Methodology. Article is devoted to a question of the maintenance operation and repair of a rolling stock of Ukraine. On the basis of theoretical probe, the situation which has developed on maintenance operation and repair of MVPS is analysed. The comparative analysis of a railway, motor and air transportation is provided. On the basis of the analysis and comparison by authors it is offered transition from scheduled preventive to system of service of railway transport to service on an actual state. Findings. According to given theoretical comparison of the put perspective in different types of transport it is possible to note that experience and features of operation rolling stock in allied industries is the base for revision and improvement of system of the maintenance rolling stock, including at various stages of its operation. Originality. This article provides the comparative theoretical analysis, concerning contents and repair system between railway, automobile and by air. Practical value. Introduction new approaches of the maintenance operation and rolling stocks repair will allow carrying out gradual transition from maintenance operation and repairing existing scheduled preventive system in repair system «on an actual state». Thus it is possible maximum cutting-down of number of sudden refusals in operation, providing high coefficient of operational readiness of a rolling stock (to 0.95. A comparative analysis of the maintenance system and repair is the basis of the transition feasibility.

  16. Applying PPM to ERP Maintenance and Continuous Improvement Initiatives

    DEFF Research Database (Denmark)

    El-Tal, Nada Maria; Fonnesbæk, Majbrit; Kræmmergaard, Pernille

    2006-01-01

    Enterprise Resource Planning Systems (ERP) has been implemented in many companies during the last decade and has gained an increasing significance. For many companies it means that the focus is no longer on how to implement the ERP system, but rather on how to maintain and improve the system...... to gain business benefits from the systems. However the ERP literature on how to do this is limited. The purpose of this article is to explore how Project Portfolio Management (PPM) from the Research and Development (R&D) literature can be applied to an ERP second wave context, when companies...... are to prioritize and select maintenance and continuous improvement initiatives. This is done by reviewing the existing literature in the fields of PPM from R&D literature and then by reviewing the existing literature about maintenance and improvement initiatives in the ERP literature, after which the two...

  17. IMPROVING THE QUALITY OF MAINTENANCE PROCESSES USING INFORMATION TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Zora Arsovski

    2008-06-01

    Full Text Available In essence, process of maintaining equipment is a support process, because it indirectly contributes to operational ability of the production process necessary for the supply chain of the new value. Taking into account increased levels of automatization and quality, this proces s becomes more and more significant and for some branches of industry, even crucial. Due to the fact that the quality of the entire process is more and more dependent on the maintenance process, these processes must be carefully designed and effectively im plemented. There are various techniques and approaches at our disposal, such as technical, logistical and intensive application of the information - communication technologies. This last approach is presented in this work. It begins with organizational goa ls, especially quality objectives. Then, maintenance processes and integrated information system structures are defined. Maintenance process quality and improvement processes are defined using a set of performances, with a special emphasis placed on effectiveness and quality economics. At the end of the work, information system for improving maintenance economics is structured. Besides theoretical analysis, work also presents results authors obtained analyzing food industry, metal processing industry an d building materials industry.

  18. The Effect of Functional Flow Diagrams on the Technical System Understanding of Apprentice Aircraft Maintenance Mechanics.

    Science.gov (United States)

    Johnson, Scott D.; Satchwell, Richard E.

    A quasiexperimental study involved 18 male students enrolled in an aircraft systems course at the University of Illinois. The control group of 10 students studied 39 schematic diagrams of aircraft systems. The treatment group of eight students studied the same schematic diagrams plus conceptual diagrams of the systems. Otherwise, the instruction…

  19. Aircraft

    Science.gov (United States)

    Hibbs, Bart D.; Lissaman, Peter B. S.; Morgan, Walter R.; Radkey, Robert L.

    1998-01-01

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gasses for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well.

  20. Aircraft

    Science.gov (United States)

    Hibbs, B.D.; Lissaman, P.B.S.; Morgan, W.R.; Radkey, R.L.

    1998-09-22

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing`s top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gases for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well. 31 figs.

  1. Improvements in Aircraft Gas Turbine Engines for the 90s

    Directory of Open Access Journals (Sweden)

    Arun Prasad

    1993-10-01

    Full Text Available The gas turbine propulsion system has been playing the most significant role in the evolution and development of present-day aircraft, and has become the limiting technology for developing most new aircraft. However, the jet engine still remains the preferred propulsion choice. Aircraft gas turbines in one form or the other, viz. turbojet, turbofan, turboprop or turboshaft, have been used in commercial passenger aircraft, high performance military aircraft and in rotary wing aircraft (helicopters. The emphasis in engine development programmes world over seems to be in reducing fuel consumption, increasing thrust and in reducing weight.

  2. Retrospective cohort mortality study of workers at an aircraft maintenance facility. I. Epidemiological results.

    Science.gov (United States)

    Spirtas, R; Stewart, P A; Lee, J S; Marano, D E; Forbes, C D; Grauman, D J; Pettigrew, H M; Blair, A; Hoover, R N; Cohen, J L

    1991-08-01

    A retrospective cohort study of 14,457 workers at an aircraft maintenance facility was undertaken to evaluate mortality associated with exposures in their workplace. The purpose was to determine whether working with solvents, particularly trichloroethylene, posed any excess risk of mortality. The study group consisted of all civilian employees who worked for at least one year at Hill Air Force Base, Utah, between 1 January 1952 and 31 December 1956. Work histories were obtained from records at the National Personnel Records Centre, St. Louis, Missouri, and the cohort was followed up for ascertainment of vital state until 31 December 1982. Observed deaths among white people were compared with the expected number of deaths, based on the Utah white population, and adjusted for age, sex, and calendar period. Significant deficits occurred for mortality from all causes (SMR 92, 95% confidence interval (95% CI) 90-95), all malignant neoplasms (SMR 90, 95% CI 83-97), ischaemic heart disease (SMR 93, 95% CI 88-98), non-malignant respiratory disease (SMR 87, 95% CI 76-98), and accidents (SMR 61, 95% CI 52-70). Mortality was raised for multiple myeloma (MM) in white women (SMR 236, 95% CI 87-514), non-Hodgkin's lymphoma (NHL) in white women (SMR 212, 95% CI 102-390), and cancer of the biliary passages and liver in white men dying after 1980 (SMR 358, 95% CI 116-836). Detailed analysis of the 6929 employees occupationally exposed to trichloroethylene, the most widely used solvent at the base during the 1950s and 1960s, did not show any significant or persuasive association between several measures of exposure to trichloroethylene and any excess of cancer. Women employed in departments in which fabric cleaning and parachute repair operations were performed had more deaths than expected from MM and NHL. The inconsistent mortality patterns by sex, multiple and overlapping exposures, and small numbers made it difficult to ascribe these excesses to any particular substance

  3. Development of Maintenance Demonstration System Based on General Aviation Aircraft of DA40%基于通航飞机DA40维修演示系统的开发

    Institute of Scientific and Technical Information of China (English)

    樊军; 吴月伟

    2012-01-01

    提高通用航空器维修人员的业务水平,是通用航空事业快速发展的基本保障.为满足通用航空维修运行的需要,研发针对通用飞机的维修演示系统平台,可有效提高维修人员的学习效率,且具有广阔的社会效益和经济效益.系统基于DA40飞机维修手册和维修培训教学大纲开发,能较好地测试演示系统各项功能的完整性,具有广泛的示范意义.%It is the guarantee to improve the ability of the maintenance men in general aircraft to maintain the rapid development of the general aviation. Research maintenance demonstration platform for general a-viation that meets the needs of maintenance operation of general aircraft which improves the learning efficiency of the aircrew and also has great social and economic benefits. The system is based on aircraft maintenance manual and training syllabus of DA40 and can test all the function of the de- monstration platform perfectly. It has a wide range of demonstration.

  4. 14 CFR 91.1443 - CAMP: Airworthiness release or aircraft maintenance log entry.

    Science.gov (United States)

    2010-01-01

    ... certificated mechanic. (c) Notwithstanding paragraph (b)(3) of this section, after maintenance, preventive... its manual that the signature of an authorized certificated mechanic or repairman constitutes...

  5. Mental health in F-111 maintenance workers: the study of Health Outcomes in Aircraft Maintenance Personnel (SHOAMP) general health and medical study.

    Science.gov (United States)

    Attia, John R; D'Este, Catherine; Schofield, Peter W; Brown, Anthony M; Gibson, Richard; Tavener, Meredith; Horsley, Keith; Harrex, Warren; Ross, James

    2006-07-01

    We sought to contrast mood disorder symptoms in F-111 aircraft Deseal/Reseal maintenance personnel with appropriate comparisons. Participants completed a comprehensive health assessment, including measures of mood disorder, self-reported mood symptom questionnaire items, and review of anxiolytic and depression medication. Multiple logistic regression was conducted for each outcome using exposure group and potential confounders as explanatory variables. There was high agreement between self-reported mood disturbance and objective tests. The exposed group was more likely to self-report previous diagnoses of depression/anxiety, had higher use of antidepressant medications, and had increased risk of diagnosis of depression/anxiety. Results were consistently strong against both comparison groups, with the exposed more likely to have mental distress and social dysfunction when compared with the Australian population. There is robust evidence for an association between F-111 Deseal/Reseal exposure and impaired mental health.

  6. Implementing a customer focused continual business improvement program to improve the maintenance process

    Energy Technology Data Exchange (ETDEWEB)

    Kharshafdjian, G.; Fisher, C.; Beres, T.; Brooks, S.; Forbes, S.; Krause, M.; McAuley, K.; Wendorf, M. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2006-07-01

    Global market pressures and increasing competition demands that successful companies establish a continual business improvement program as part of implementing its business strategy. Such programs must be driven by the definition of quality from the customer's perspective. This customer quality focus often requires a change in all aspects of the business including products, services, processes and culture. This paper will describe how Atomic Energy of Canada Limited implemented a Continual Business Improvement Program in their Nuclear Laboratories Business Unit. In particular, to review how the techniques were applied to improve the maintenance process and the status of the project. Customer (internal users of the processes at CRL) feedback has shown repeatedly there is dissatisfaction of the maintenance process. Customers complain about jobs not getting done to schedule or being deferred. A project has been launched with the following goals: to improve the maintenance process customer satisfaction and increase trades wrench time by 30 minutes / trade / day. DMAIC (Define-Measure-Analyze-Improve-Control) methodology was applied to find out the Root Cause(s) of the problem, provide solutions, and implement improvements. The expected Operational Benefits include: Executing work efficiently to quality standards and business performance of the site, improve maintenance efficiencies, reduce cycle time for maintenance process and improve process yield, and improve customer and employee satisfaction. (author)

  7. A Fixed-Wing Aircraft Simulation Tool for Improving the efficiency of DoD Acquisition

    Science.gov (United States)

    2015-10-05

    05/2015 Oct 2008-Sep 2015 A Fixed- Wing Aircraft Simulation Tool for Improving the Efficiency of DoD Acquisition Scott A. Morton and David R...multi-disciplinary fixed- wing virtual aircraft simulation tool incorporating aerodynamics, structural dynamics, kinematics, and kinetics. Kestrel allows...testing. UU UU UU UU 9 Kevin Newmeyer 703-812-4417 1 A Fixed- Wing Aircraft Simulation Tool for Improving the Efficiency of DoD Acquisition

  8. 机务人员疲劳致因影响分析%Analysis of Fatigue Causes for Aircraft Maintenance Personnel

    Institute of Scientific and Technical Information of China (English)

    张晓全; 潘晶; 王欢; 刘畅

    2013-01-01

    It was held by the authors that fatigue can seriously impact aircraft maintenance activities, and analyzing fatigue causes of maintenance personnel can effectively prevent fatigue from setting in. In order to analyze main fatigue causes and their effects on the activities in a certain aircraft maintenance factoy in China,a method combining the methods of DEMATEL and ANP was worked out. The empirical results show that health status, scheduling system, staffing, sleeping are playing critical roles. In view of four key factors above, countermeasures are proposed to reduce fatigue risk.%机务人员疲劳严重影响飞机维修活动的安全进行,分析机务人员疲劳致因有助于有效防止疲劳引起的人为差错.为确定疲劳致因的影响关系和重要程度,结合中国某维修厂的具体情况,将决策实验与评价实验室方法(DEMATEL)和网络分析法(ANP)相结合,来确定主要疲劳致因的影响作用.计算结果显示,健康状态、排班制度、人员岗位安排以及睡眠状况为该维修厂主要疲劳致因.鉴于以上4个关键的疲劳致因,提出相应的缓解措施,从而实现降低疲劳风险的目的.

  9. Education as a Basic Element of Improving Professional Important Qualities of Aviation Technical Maintenance Personnel

    Directory of Open Access Journals (Sweden)

    Gorbačovs Oļegs

    2016-12-01

    Full Text Available In this article the importance of professional qualities, competence and their increase, directly dependent on the training of aviation technical maintenance personnel and determination the level of flight safety is covered. This publication analyses necessary training and requirements for aviation technical personnel involved in aircraft maintenance, as well as the requirements for aviation training organizations, defined as per Part-147, for such personnel preparation and training.

  10. Aviation Maintenance Technology. Airframe. A203. Aircraft Fabric Covering, Painting, and Finishing. Instructor Material.

    Science.gov (United States)

    Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This teacher's guide is designed to aid teachers in leading students through a module on airframe building and repair, including fabric covering, painting, and finishing. The module contains two units that cover the following topics: (1) inspecting, testing, and installing aircraft fabric coverings and (2) applying dope, paint, and trim. Each unit…

  11. The Phychological Impact of Attributional Training on Aircraft Maintenance Management%归因训练对航空机务人员身心作用研究

    Institute of Scientific and Technical Information of China (English)

    王丹; 宋燕峰; 苗丹民

    2011-01-01

    目的 探索归因训练对机务人员的心理影响,探讨航空机务人员心理服务新模式,为新时期军队建设提供科学依据.方法 本研究采用归因风格训练,以随机整群抽取的空军航空兵一线机务官兵490人作为样本进行研究.对样本官兵实施归因风格训练7个月后,用归因风格量表(ASQ)进行测量.结果 实施归因训练后,官兵的归因风格各因子、应付风格各因子明显提高(P<0.05).结论 归因风格训练使航空机务人员心理健康水平和生活满意度显著提高;实施心理训练后心理健康状况有明显改善;改变归因风格对机务人员心理健康有促进作用.%Objective To explore the psychological impact of attribution training on aircraft maintenance personnel and study new mode of their psychological services to provide scientific basis for army building in the new period. Methods This research is carried out by adopting attribution style training, randomly sampling a whole group of 490 first - line maintenance officers from the aviation personnel in air service,and taking them as samples. After 7 months' attribution style training,the sampled officers were measured according to the attribution style questionnaire ( ASQ) . Results After implementation of attribution training, their factors of attribution style and handling style were improved dramatically ( P < 0. 05). Conclusion Attribution training notably lifts level of psychological health and life satisfaction for aircraft maintenance personnel. After having accepted psychological training, their psychological health is improved obviously. And changing attribution style can promote the psychological health of maintenance personnel.

  12. Integrated maintenance support scheduling method of multi-carrier aircrafts%舰载机多机一体化机务保障调度方法

    Institute of Scientific and Technical Information of China (English)

    韩维; 苏析超; 陈俊锋

    2015-01-01

    为了有效提升舰载机多机机务保障的效率和保障人员的利用率,根据单机机务保障流程约束特性,建立了基于多计划评审技术网络的多目标多机一体化机务保障调度模型。针对问题的求解,提出了一种自适应混合差分进化算法。首先根据调度的网络化排队过程,设计了基于事件调度策略的解码方法。其次为了协调算法“探索”与“开发”的能力,引入了自适应的变异操作和交叉、变异参数控制。再次,针对工序块的平行组合排列特征,提出了4种邻域结构,进而在算法框架中嵌入了一种自适应多邻域局部搜索策略。最后通过仿真实验验证了模型和算法的可行性和有效性。%In order to improve the maintenance support efficiency and support personnel availability of multi-carrier aircrafts effectively,according to the constraint characteristics of maintenance support process for single-carrier aircraft,a multi-objective integrated maintenance support scheduling model of multi-carrier air-crafts based on multiple program evaluation and review technique networks is established.To solve the pro-blem,a self-adaptive hybrid differential evolution algorithm is presented.First,a decoding method based on event scheduling is designed according to networked queuing process of scheduling.Second,for coordinating the exploration and exploitation in algorithm,a self-adaptive mutation operation,an adaptive control strategy of crossover and mutation parameters are introduced.Third,in view of the characteristics of parallel-arrangement of process blocks,four kinds of neighborhood structure are defined,and then a novel local search based on the newly defined neighborhoods is presented and imbedded in the SaHDE algorithm.The simulation results show the feasibility of the model and the effectiveness of the algorithm.

  13. The NASA aircraft noise prediction program improved propeller analysis system

    Science.gov (United States)

    Nguyen, L. Cathy

    1991-01-01

    The improvements and the modifications of the NASA Aircraft Noise Prediction Program (ANOPP) and the Propeller Analysis System (PAS) are described. Comparisons of the predictions and the test data are included in the case studies for the flat plate model in the Boundary Layer Module, for the effects of applying compressibility corrections to the lift and pressure coefficients, for the use of different weight factors in the Propeller Performance Module, for the use of the improved retarded time equation solution, and for the effect of the number grids in the Transonic Propeller Noise Module. The DNW tunnel test data of a propeller at different angles of attack and the Dowty Rotol data are compared with ANOPP predictions. The effect of the number of grids on the Transonic Propeller Noise Module predictions and the comparison of ANOPP TPN and DFP-ATP codes are studied. In addition to the above impact studies, the transonic propeller noise predictions for the SR-7, the UDF front rotor, and the support of the enroute noise test program are included.

  14. Challenge to Aviation: Hatching a Leaner Pterosauer. [Improving Commercial Aircraft Design for Greater Fuel Efficiency

    Science.gov (United States)

    Moss, F. E.

    1975-01-01

    Modifications in commercial aircraft design, particularly the development of lighter aircraft, are discussed as effective means of reducing aviation fuel consumption. The modifications outlined include: (1) use of the supercritical wing; (2) generation of the winglet; (3) production and flight testing of composite materials; and, (4) implementation of fly-by-wire control systems. Attention is also given to engineering laminar air flow control, improving cargo payloads, and adapting hydrogen fuels for aircraft use.

  15. Improving bioretention/biofiltration performance with restorative maintenance.

    Science.gov (United States)

    Brown, Robert A; Hunt, William F

    2012-01-01

    One of the most popular Stormwater Control Measures is bioretention, or biofiltration. Anecdotal evidence suggests that well-designed bioretention cells are often not adequately installed and that maintenance is lacking, leading to less-than-adequate water storage volume and/or surface infiltration rates post-construction. In March 2009, two sets of bioretention cells were repaired by excavating the top 75 mm of fill media, increasing the bioretention surface storage volume by nearly 90% and the infiltration rate by up to a factor of 10. Overflow volume decreased from 35 and 37% in the pre-repair state for two different sets of cells, respectively, to 11 and 12%. Nearly all effluent pollutant loads exiting the post-repair cells were lower than their pre-repair conditions. The bioretention systems employed two different media depths (0.6 and 0.9 m). The deeper media cells discharged less outflow volume than the shallower cells, with 10-11% more runoff volume leaving as exfiltration from the 0.9-m than from the 0.6-m media depth cells. This study showed that maintenance is both critical and beneficial to restore otherwise poorly performing bioretention. Moreover, while deeper media cells did outperform the shallower systems, the improvement in this case was somewhat modest vis-à-vis additional construction costs.

  16. Test and Evaluation of Ultrasonic Additive Manufacturing (UAM) for a Large Aircraft Maintenance Shelter (LAMS) Baseplate

    Science.gov (United States)

    2015-03-26

    to machine . A new manufacturing process is emerging called additive manufacturing (AM) and its beginnings can be traced to the 1980s. AM, as...opposed to subtractive manufacturing , builds a design up layer by layer into a component saving time and machining cost in addition to granting a wide...TEST AND EVALUATION OF ULTRASONIC ADDITIVE MANUFACTURING (UAM) FOR A LARGE AREA MAINTENANCE

  17. Hearing impairment in F-111 maintenance workers: the study of health outcomes in aircraft maintenance personnel (SHOAMP) general health and medical study.

    Science.gov (United States)

    Guest, Maya; Boggess, May; Attia, John; D'Este, Catherine; Brown, Anthony; Gibson, Richard; Tavener, Meredith; Gardner, Ian; Harrex, Warren; Horsley, Keith; Ross, James

    2010-11-01

    We sought to examine hearing loss in a group from the Royal Australian Air Force who undertook fuel tank maintenance on F-111 aircraft, with exposure to formulations containing ototoxins, relative to two different comparison groups. Using pure-tone audiometry, hearing thresholds were assessed in 614 exposed personnel, 513 technical-trade comparisons (different base, same job), and 403 non-technical comparisons (same base, different job). We calculated percentage loss of hearing (PLH) and used regression models to examine whether there was an association between PLH and F-111 fuel tank maintenance, adjusting for possible confounders. In addition, the difference between the observed hearing thresholds and the expected thresholds based on an otologically normal population (ISO-7029-2003) was determined. The PLH ranged from nil to 96 (median 1.5, quartiles 0.3, 5.5). A logistic regression model showed no statistically significant difference in PLH among the three exposure groups (exposed vs. non-technical controls 1.1: 95% CI 0.7, 2.0 and exposed vs. technical OR 0.9: 95% CI 0.6, 1.3). The model also highlighted a number of other risk factors for PLH including age, tinnitus, smoking, depression, and use of depression medications. However, at all eight frequencies measured, all populations had lower than expected hearing thresholds based on published ISO-7029 medians. Although there was no difference in PLH between the three exposure groups, the study did reveal a high degree of hearing loss between the 3 groups and a normal population. © 2010 Wiley-Liss, Inc.

  18. CREW CHIEF: A computer graphics simulation of an aircraft maintenance technician

    Science.gov (United States)

    Aume, Nilss M.

    1990-01-01

    Approximately 35 percent of the lifetime cost of a military system is spent for maintenance. Excessive repair time is caused by not considering maintenance during design. Problems are usually discovered only after a mock-up has been constructed, when it is too late to make changes. CREW CHIEF will reduce the incidence of such problems by catching design defects in the early design stages. CREW CHIEF is a computer graphic human factors evaluation system interfaced to commercial computer aided design (CAD) systems. It creates a three dimensional man model, either male or female, large or small, with various types of clothing and in several postures. It can perform analyses for physical accessibility, strength capability with tools, visual access, and strength capability for manual materials handling. The designer would produce a drawing on his CAD system and introduce CREW CHIEF in it. CREW CHIEF's analyses would then indicate places where problems could be foreseen and corrected before the design is frozen.

  19. Dextre: Improving maintenance operations on the International Space Station

    Science.gov (United States)

    Coleshill, Elliott; Oshinowo, Layi; Rembala, Richard; Bina, Bardia; Rey, Daniel; Sindelar, Shelley

    2009-05-01

    The Special Purpose Dexterous Manipulator (SPDM), known as "Dextre", is currently slated to launch in February 2008 for deployment on the International Space Station (ISS) as the final component of Canada's Mobile Servicing System (MSS). Dextre's primary role on the Space Station is to perform repair and replacement (R&R) maintenance tasks on robotically compatible hardware such as Orbital Replaceable Units (ORUs), thereby eventually easing the burden on the ISS crew. This burden on the on-orbit crew translates practically into crew time being a limited resource on the ISS, and as such, finding ways to assist the crew in performing their tasks or offloading the crew completely when appropriate is a bonus to the ISS program. This is already accomplished very effectively by commanding as many non-critical robotics tasks as possible, such as powering up and free-space maneuvering of the Space Station Remote Manipulator System (SSRMS), known as "Canadarm2", from the Ground. Thus, beyond its primary role, and based on an increasing clarity regarding the challenges of external maintenance on the ISS, Dextre is being considered for use in a number of ways with the objective of improving ISS operations while reducing and optimizing the use of crew time through the use of ground control for various tasks, pre-positioning hardware, acting as a temporary storage platform to break an Extra Vehicular Activity (EVA) day into manageable timelines, and extending the physical reach and range of the Canadarm2. This paper discusses the planned activities and operations for Dextre an rationale for how these will help optimize the use of crew resources on the ISS.

  20. An analysis of the costs and benefit in improving the T56-A-427 interconnector harness end and mating thermocouple end connector under the aircraft engine Component Improvement Program (CIP)

    OpenAIRE

    Murphy, Thomas Joseph

    1994-01-01

    Approved for public release; distribution is unlimited. This thesis is a study validating the cost effectiveness of the Component Improvement Program for aircraft engines. It determines the costs and benefits derived from the Navy incorporating Power Plant Change 111 which improved the interconnector harness end and mating thermocouple end connector of the T56-A-427 engine. Useful maintenance data pertaining to this component was extracted from the Naval Logistics Data Analysis (NALDA) sys...

  1. Using satellites to improve civilian aircraft surveillance coverage

    Science.gov (United States)

    Mcgraw, K.

    1984-01-01

    Surveillance of aircraft is presently accomplished through the use of terrestrial based secondary radar sensors, which are capable of interrogating transponders aboard aircraft. Transponder responses provide the basis for determining radial distance by measuring round-trip signal time while antenna angular position is used to determine azimuthal position. These interrogating radar beams are line-of-sight and thus have their coverage obscured by mountains and tall buildings. The addition of more radar sites is rendered unfeasible by the lack of easy access to the required additional site locations. A possible solution to this problem is to deploy satellites that interrogate transponder-equipped aircraft from a position that provides an unobstructed view.

  2. Standard Test Method for Effects of Cleaning and Chemical Maintenance Materials on Painted Aircraft Surfaces

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This test method covers determination of the effects of cleaning solutions and liquid cleaner concentrates on painted aircraft surfaces (Note 1). Streaking, discoloration, and blistering may be determined visually. Softening is determined with a series of specially prepared pencils wherein determination of the softest pencil to rupture the paint film is made. Note 1—This test method is applicable to any paint film that is exposed to cleaning materials. MIL-PRF-85285 has been selected as a basic example. When other paint finishes are used, refer to the applicable material specification for panel preparation and system curing prior to testing. 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user ...

  3. Comparison of internal dose measures of solvents in breath, blood and urine and genotoxic changes in aircraft maintenance personnel.

    Science.gov (United States)

    Lemasters, G K; Lockey, J E; Olsen, D M; Selevan, S G; Tabor, M W; Livingston, G K; New, G R

    1999-02-01

    Solvents and fuels are in widespread use both in civilian and military populations. 1,1,1-trichloroethane (TCA), xylene, toluene, methyl ethyl ketone (MEK) and methylene chloride are found in a variety of compounds including degreasing agents, paints, coatings, pesticides and paint strippers. Toluene and xylene are also found in fuels, which are complex mixtures of hundreds of agents. The purpose of this investigation was twofold. The first was to determine the optimum medium to measure internal dose of solvents comparing blood, urine and breath. The second was to determine if low level exposures were associated with genotoxic changes after a short-term exposure of fifteen or thirty weeks. To accomplish the first goal a pilot study was initiated involving eight volunteers who worked in aircraft maintenance including sheet metal, painting and assembly mechanic jobs. Industrial hygiene measurements were evaluated over 30 working days. Breath, blood and a 24-hour urine sample were collected twice to compare internal dose parameters. To achieve the second goal, 58 newly hired subjects were monitored prior to exposure and over 30 weeks to determine if there were genotoxic changes as a result of solvent and/or fuel exposure as measured by sister chromatid exchanges (SCEs) and micronuclei (MN). Exposure groups included workers involved in sheet metal (fuel cell) activities, painting, fueling operations and flight line. Results of the pilot study demonstrated that industrial hygiene air samples and internal breath measures taken on the same day were highly correlated for measuring TCA (r = 0.93) and toluene (r = 0.90) but was not as well correlated for the other compounds. Breath measures were more sensitive for measuring low level exposure than were either analytes in blood or 24-hour urine samples; these latter two measures were usually below the limit of detection. A small but statistically significant increase in the frequency of SCEs occurred after 30 weeks of

  4. Improving Access to Military Aircraft During Civilian Wildfires

    Science.gov (United States)

    2015-12-01

    natural regenerative properties and which is beneficial for long-term forest health. In an undated pamphlet, CAL FIRE (the California Department of...With its long history , the federal civilian wildfire community has utilized strategic planning to guide their “… Comprehensive national aviation...suppressing wildfires from the air. Two examples are California and Colorado. While California has a long history of utilizing aircraft in the suppression

  5. Effect of exposure to a mixture of solvents and noise on hearing and balance in aircraft maintenance workers.

    Science.gov (United States)

    Prasher, Deepak; Al-Hajjaj, Haifa; Aylott, Susan; Aksentijevic, Aleksander

    2005-01-01

    Aircraft maintenance workers are exposed to a mixture of solvents in the presence of intermittent noise. For this study these workers exposed to solvent mix and noise, were compared with mill workers exposed to noise alone, printed circuit board operatives exposed to solvents alone and those exposed to none who acted as controls. Tympanometry, acoustic reflex thresholds, transient and distortion product otoacoustic emissions, auditory brainstem potentials, nystagmography and posturography were examined. There was a significant effect on pure tone thresholds for both noise and solvents+noise. The distortion product otoacoustic emissions declined with frequency and exhibited lower DP amplitude with noise compared to solvents and noise group. The transient emissions showed a similar effect. Over 32% of subjects with solvent and noise exposure had abnormalities of the auditory brainstem responses in terms of interwave interval prolongation. The mean acoustic reflex thresholds showed a pattern of differences which differentiate noise from solvent and noise groups. The contralateral pathway appears to be differentially affected by solvent exposure. 32% of subjects in the solvents and noise group had an abnormal posturographic finding. In the solvents and noise group 74% had abnormalities of saccades, 56% of pursuit and 45% of optokinetic nystagmus.

  6. The Feasibility of Implementing an Expert System for Aircraft Maintenance Discrepancy Scheduling with the Naval Aviation Logistics Command Management Information system (NALCOMIS).

    Science.gov (United States)

    1985-09-01

    priority rating is medium c. Rule .gOBJECT: BOOK I. sWOTS ENIR-IE9- Title A Guide To Expert Systems * Author Waterman, Donald A. Publisher Addison...responsibility of the MCO. It also falls to him to maintain historical aircraft files and monitor 3M documentation. VIDS boards and material...Reduce awaiting parts inventory levels at the SSC. - Reduce the administrative burden of maintenance personnel in meeting 3M system requirements

  7. Single-Lever Power Control for General Aviation Aircraft Promises Improved Efficiency and Simplified Pilot Controls

    Science.gov (United States)

    Musgrave, Jeffrey L.

    1997-01-01

    General aviation research is leading to major advances in internal combustion engine control systems for single-engine, single-pilot aircraft. These advances promise to increase engine performance and fuel efficiency while substantially reducing pilot workload and increasing flight safety. One such advance is a single-lever power control (SLPC) system, a welcome departure from older, less user-friendly, multilever engine control systems. The benefits of using single-lever power controls for general aviation aircraft are improved flight safety through advanced engine diagnostics, simplified powerplant operations, increased time between overhauls, and cost-effective technology (extends fuel burn and reduces overhaul costs). The single-lever concept has proven to be so effective in preliminary studies that general aviation manufacturers are making plans to retrofit current aircraft with the technology and are incorporating it in designs for future aircraft.

  8. Power plant maintenance scheduling using ant colony optimization: an improved formulation

    Science.gov (United States)

    Foong, Wai Kuan; Maier, Holger; Simpson, Angus

    2008-04-01

    It is common practice in the hydropower industry to either shorten the maintenance duration or to postpone maintenance tasks in a hydropower system when there is expected unserved energy based on current water storage levels and forecast storage inflows. It is therefore essential that a maintenance scheduling optimizer can incorporate the options of shortening the maintenance duration and/or deferring maintenance tasks in the search for practical maintenance schedules. In this article, an improved ant colony optimization-power plant maintenance scheduling optimization (ACO-PPMSO) formulation that considers such options in the optimization process is introduced. As a result, both the optimum commencement time and the optimum outage duration are determined for each of the maintenance tasks that need to be scheduled. In addition, a local search strategy is presented in this article to boost the robustness of the algorithm. When tested on a five-station hydropower system problem, the improved formulation is shown to be capable of allowing shortening of maintenance duration in the event of expected demand shortfalls. In addition, the new local search strategy is also shown to have significantly improved the optimization ability of the ACO-PPMSO algorithm.

  9. LCC-OPS: Life Cycle Cost Application in Aircraft Operations

    NARCIS (Netherlands)

    Suwondo, E.

    2007-01-01

    Observation of current practices in aircraft operations and maintenance shows limited consideration of cost savings applied by aircraft modifications, maintenance program optimisation and aircraft selection. This is due to hidden (maintenance dependent) costs and difficulties in quantifying the

  10. LCC-OPS: Life Cycle Cost Application in Aircraft Operations

    NARCIS (Netherlands)

    Suwondo, E.

    2007-01-01

    Observation of current practices in aircraft operations and maintenance shows limited consideration of cost savings applied by aircraft modifications, maintenance program optimisation and aircraft selection. This is due to hidden (maintenance dependent) costs and difficulties in quantifying the util

  11. Multi-Sensor Fusion with Interacting Multiple Model Filter for Improved Aircraft Position Accuracy

    Directory of Open Access Journals (Sweden)

    Changho Lee

    2013-03-01

    Full Text Available The International Civil Aviation Organization (ICAO has decided to adopt Communications, Navigation, and Surveillance/Air Traffic Management (CNS/ATM as the 21st century standard for navigation. Accordingly, ICAO members have provided an impetus to develop related technology and build sufficient infrastructure. For aviation surveillance with CNS/ATM, Ground-Based Augmentation System (GBAS, Automatic Dependent Surveillance-Broadcast (ADS-B, multilateration (MLAT and wide-area multilateration (WAM systems are being established. These sensors can track aircraft positions more accurately than existing radar and can compensate for the blind spots in aircraft surveillance. In this paper, we applied a novel sensor fusion method with Interacting Multiple Model (IMM filter to GBAS, ADS-B, MLAT, and WAM data in order to improve the reliability of the aircraft position. Results of performance analysis show that the position accuracy is improved by the proposed sensor fusion method with the IMM filter.

  12. Aircraft Ground Operation, Servicing, Fluid Lines and Fittings, Mechanics Privileges and Limitations, and Maintenance Publications, Forms and Records (Course Outline), Aviation Mechanics 1 (Power and Frame): 9073.02.

    Science.gov (United States)

    Dade County Public Schools, Miami, FL.

    The course outline consists of five instructional blocks of several units each: (1) Aircraft Ground Operation and Servicing; (2) Fluid Lines and Fittings; (3) Mechanics Requirements, Privileges and Limitations; (4) Maintenance Publications; and, (5) Maintenance forms and Records. It is a basic course of knowledge and skills necessary to any…

  13. Reliability and Maintainability Model (RAM): User and Maintenance Manual. Part 2; Improved Supportability Analysis

    Science.gov (United States)

    Ebeling, Charles E.

    1996-01-01

    This report documents the procedures for utilizing and maintaining the Reliability & Maintainability Model (RAM) developed by the University of Dayton for the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC). The purpose of the grant is to provide support to NASA in establishing operational and support parameters and costs of proposed space systems. As part of this research objective, the model described here was developed. This Manual updates and supersedes the 1995 RAM User and Maintenance Manual. Changes and enhancements from the 1995 version of the model are primarily a result of the addition of more recent aircraft and shuttle R&M data.

  14. [Improved program maintenance of the CIRCIS dosimetric planning system].

    Science.gov (United States)

    Sevast'ianov, A I; Liutova, N A; Ratner, T G

    1983-03-01

    A special computer complex CIRCIS (Informatique, France) is used in the All-Union Cancer Research Center, USSR AMS, for the dosimetric planning of radiotherapy on 5 gamma-beam units and electron accelerator. Mathematical maintenance of the complex includes programs of the calculation of dose distribution for gamma-, inhibition and electron radiation but has no program of the calculation of the time of irradiation. The authors have devised and introduced into the complex such a program in the Fortran language that makes it possible to calculate within 2-3 min the time of irradiation for multifield rotation therapy using several units as a time, thus expediting the dosimetric planning for patients' irradiation.

  15. How to Solve Problem of Seal for Aircraft Structure Maintenance%飞机结构密封与失效修理

    Institute of Scientific and Technical Information of China (English)

    王哲

    2014-01-01

    为提高飞机增压舱的密封能力,给出了飞机结构密封失效的修理程序、方法、试验验证、典型结构密封的措施等,以求达到增压舱正常加压和减缓机体腐蚀发生,保证飞机在寿命期内安全飞行。%In order to enhance the sealing capacity of the pressure cabin, a set of proposals regarding the failure of the sealing in the aircraft structure is presented, including maintenance procedures, ways and means, tests, sealing options of typical structures, etc. By doing this, the normal pressurization of the pressure cabin can be ob-tained and the structure eroding can be delayed to ensure the flying security during the aircraft flight life.

  16. Mortality and cancer incidence of aircraft maintenance workers exposed to trichloroethylene and other organic solvents and chemicals: extended follow up.

    Science.gov (United States)

    Blair, A; Hartge, P; Stewart, P A; McAdams, M; Lubin, J

    1998-03-01

    To extend the follow up of a cohort of 14,457 aircraft maintenance workers to the end of 1990 to evaluate cancer risks from potential exposure to trichloroethylene and other chemicals. The cohort comprised civilians employed for at least one year between 1952 and 1956, of whom 5727 had died by 31 December 1990. Analyses compared the mortality of the cohort with the general population of Utah and the mortality and cancer incidence of exposed workers with those unexposed to chemicals, while adjusting for age, sex and calendar time. In the combined follow up period (1952-90), mortality from all causes and all cancer was close to expected (standardised mortality ratios (SMRs) 97 and 96, respectively). Significant excesses occurred for ischaemic heart disease (SMR 108), asthma (SMR 160), and cancer of the bone (SMR 227), whereas significant deficits occurred for cerebrovascular disease (SMR 88), accidents (SMR 70), and cancer of the central nervous system (SMR 64). Workers exposed to trichloroethylene showed non-significant excesses for non-Hodgkin's lymphoma (relative risk (RR) 2.0), and cancers of the oesophagus (RR 5.6), colon (RR 1.4), primary liver (RR 1.7), breast (RR 1.8), cervix (RR 1.8), kidney (RR 1.6), and bone (RR 2.1). None of these cancers showed an exposure-response gradient and RRs among workers exposed to other chemicals but not trichloroethylene often had RRs as large as workers exposed to trichloroethylene. Workers exposed to solvents other than trichloroethylene had slightly increased mortality from asthma, non-Hodgkin's lymphoma, multiple myeloma, and breast cancer. These findings do not strongly support a causal link with trichloroethylene because the associations were not significant, not clearly dose-related, and inconsistent between men and women. Because findings from experimental investigations and other epidemiological studies on solvents other than trichloroethylene provide some biological plausibility, the suggested links between these

  17. Maintenance of normoglycemia may improve outcome in acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    Sruthi S Nair

    2017-01-01

    Full Text Available Introduction: Several studies have shown that high admission glucose is associated with poor outcomes after stroke, but the impact of maintenance of normoglycemia on functional outcome during hospitalization for acute ischemic stroke is less well established. Aims: The aim of this study was to examine the independent association of postadmission glycemic status in the 1st week with 3-month functional outcome in patients with acute ischemic stroke. Methods: Patients with acute ischemic stroke admitted within 48 h of symptom onset with National Institutes of Health Stroke Scale (NIHSS of ≥4 were selected from a prospectively maintained database by chart review. Demographic data, risk factors, NIHSS, and blood glucose values in the 1st week were collected. The primary outcome was Modified Rankin Scale (mRS score at 3 months (good outcome-mRS ≤2. Results: Over 3 years, 342 patients were enrolled with 220 (64.32% males. Mean age was 60.5 ± 13.4 years, and median admission score on NIHSS was 10 (interquartile range: 6–16. Blood glucose values persistently <140 mg/dl in the 1st week were associated with a good 3-month functional outcome in univariate analysis (P = 0.036. Hypoglycemic episodes occurred only in 11 (3.22% patients. Conclusions: Blood glucose values persistently below 140 mg/dl in the 1st week after acute ischemic stroke were associated with a favorable outcome in our study. Future clinical trials are needed to confirm these findings.

  18. 14 CFR 121.380a - Transfer of maintenance -records.

    Science.gov (United States)

    2010-01-01

    ... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Maintenance, Preventive Maintenance, and Alterations... aircraft shall transfer to the purchaser, at the time of sale, the following records of that aircraft,...

  19. First Lean, then modularisation: improving the maintenance of offshore wind turbines

    DEFF Research Database (Denmark)

    Petersen, Kristian R.; Madsen, Erik Skov; Bilberg, Arne

    2016-01-01

    Purpose – This paper aims to explore how maintenance tasks can be planned and executed in a smarter way and, consequently, how the operations and maintenance of offshore wind power installations can be improved through modularisation. Design/methodology/approach – This is a case study of one...... of Europe’s leading offshore wind power operators with more than 1,000 wind turbine generators in operation. By focusing on this company, in-depth insights into its operations and maintenance processes are investigated. Findings – Lean is identified to constitute an important first step before...

  20. Modeling the impact of improved aircraft operations technologies on the environment and airline behavior

    Science.gov (United States)

    Foley, Ryan Patrick

    The overall goal of this thesis is to determine if improved operations technologies are economically viable for US airlines, and to determine the level of environmental benefits available from such technologies. Though these operational changes are being implemented primarily with the reduction of delay and improvement of throughput in mind, economic factors will drive the rate of airline adoption. In addition, the increased awareness of environmental impacts makes these effects an important aspect of decision-making. Understanding this relationship may help policymakers make decisions regarding implementation of these advanced technologies at airports, and help airlines determine appropriate levels of support to provide for these new technologies. In order to do so, the author models the behavior of a large, profit-seeking airline in response to the introduction of advanced equipage allowing improved operations procedures. The airline response included changes in deployed fleet, assignment of aircraft to routes, and acquisition of new aircraft. From these responses, changes in total fleet-level CO2 emissions and airline profit were tallied. As awareness of the environmental impact of aircraft emissions has grown, several agencies (ICAO, NASA) have moved to place goals for emissions reduction. NASA, in particular, has set goals for emissions reduction through several areas of aircraft technology. Among these are "Operational Improvements," technologies available in the short-term through avionics and airport system upgrades. The studies in this thesis make use of the Fleet-Level Environmental Evaluation Tool (FLEET), a simulation tool developed by Purdue University in support of a NASA-sponsored research effort. This tool models the behavior of a large, profit-seeking airline through an allocation problem. The problem is contained within a systems dynamics type approach that allows feedback between passenger demand, ticket price, and the airline fleet composition

  1. 25 CFR 170.808 - Can BIA Road Maintenance Program funds be used to improve IRR transportation facilities?

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Can BIA Road Maintenance Program funds be used to improve... THE INTERIOR LAND AND WATER INDIAN RESERVATION ROADS PROGRAM BIA Road Maintenance § 170.808 Can BIA Road Maintenance Program funds be used to improve IRR transportation facilities? No. BIA...

  2. Innovative predictive maintenance concepts to improve life cycle management

    NARCIS (Netherlands)

    Tinga, T.

    2014-01-01

    For naval systems with typically long service lives, high sustainment costs and strict availability requirements, an effective and efficient life cycle management process is very important. In this paper four approaches are discussed to improve that process: physics of failure based predictive maint

  3. Maintenance of hyperglycaemia does not improve performance in a ...

    African Journals Online (AJOL)

    to improve performance during prolonged exercise (> 90 min duration) 12, 15 ... suggests that there is a muscle glycogen-sparing effect.1, 9,16. However ... Department of Human Biology. University ... Subjects were requested to perform the same type of training for .... The mean time, power output and heart rate for ETT and.

  4. 某新型飞机维修模拟训练系统%Maintenance Simulation System of a New Type Aircraft

    Institute of Scientific and Technical Information of China (English)

    张伟; 库丽媛

    2011-01-01

    介绍了某新型飞机维修模拟训练系统的设计思路以及系统组成和特点,并结合系统的实现讨论了模拟仿真技术应用于装备维修的现实意义.实践证明,应用该系统开展飞机维修模拟训练解决了部队由于维修保障训练设备缺乏,机务人员难以进行全专业综合保障维修训练的难题,大大缩短了新机维修保障训练周期,节约了大量的装备维修保障经费.%The design concept of a new type aircraft maintenance simulation system is introduced The components, features and value of the simulation system are also described Practice shows that application of the simulation system can meet the requirements of aircraft maintenance training, shorten training cycle and save training funds.

  5. A Simulation Model for Machine Efficiency Improvement Using Reliability Centered Maintenance: Case Study of Semiconductor Factory

    Directory of Open Access Journals (Sweden)

    Srisawat Supsomboon

    2014-01-01

    Full Text Available The purpose of this study was to increase the quality of product by focusing on the machine efficiency improvement. The principle of the reliability centered maintenance (RCM was applied to increase the machine reliability. The objective was to create preventive maintenance plan under reliability centered maintenance method and to reduce defects. The study target was set to reduce the Lead PPM for a test machine by simulating the proposed preventive maintenance plan. The simulation optimization approach based on evolutionary algorithms was employed for the preventive maintenance technique selection process to select the PM interval that gave the best total cost and Lead PPM values. The research methodology includes procedures such as following the priority of critical components in test machine, analyzing the damage and risk level by using Failure Mode and Effects Analysis (FMEA, calculating the suitable replacement period through reliability estimation, and optimizing the preventive maintenance plan. From the result of the study it is shown that the Lead PPM of test machine can be reduced. The cost of preventive maintenance, cost of good product, and cost of lost product were decreased.

  6. [The algorithm for the medical maintenance of the aircraft personnel suffering from chronic sensorineural impairment of hearing].

    Science.gov (United States)

    Pankova, V B; Skryabina, L Yu; Barkhatova, O A

    2016-01-01

    The present study was designed to systematize the causes underlying the development of chronic sensorineural impairment of hearing in the aircraft personnel engaged in commercial aviation of the Russian Federation. A detailed clinical and audiological picture of chronic sensorineural loss of hearing in the aircraft personnel is presented with special reference to the criteria accepted in the civil aviationfor the evaluation of professional suitability and occupational selection in terms of hearing conditions. The study has demonstrated the paramount importance of the aviation medical expertise for the flight safety control in civil aviation. We analyzed the results of the audiological examination of the aircraft personnel suffering from chronic sensorineural impairment of hearing and proposed the algorithm for the rehabilitation of such subjects taking into consideration the stage of the chronic process.

  7. Improving Effectiveness Of ELearning In Maintenance Using Interactive 3D

    CERN Document Server

    Baboo, S Santhosh

    2009-01-01

    In aerospace and defense, training is being carried out on the web by viewing PowerPoint presentations, manuals and videos that are limited in their ability to convey information to the technician. Interactive training in the form of 3D is a more cost effective approach compared to creation of physical simulations and mockups. This paper demonstrates how training using interactive 3D simulations in elearning achieves a reduction in the time spent in training and improves the efficiency of a trainee performing the installation or removal.

  8. Study on the Applications of Corrosion Inhibitor in Military Aircraft Maintenance%缓蚀剂在军用飞机维护中的应用研究

    Institute of Scientific and Technical Information of China (English)

    孙祚东; 李云仲; 韦利军

    2014-01-01

    Objective To study the validity of the hard film water-displacing corrosion inhibitor which is used in the joint sections of military aircraft in marine environment. Methods The performance of corrosion inhibitor was evaluated through functional penetration test and environment spectrum accelerated corrosion contrast test, and the practical applica-tion effect was verified by the lead probation on typical structure sections of a certain aircraft. Results The penetration rate of the corrosion inhibitor was 85%. The applications of corrosion inhibitor in the military aircraft internal structures could effectively retard the development of corrosion,and postpone the occurrence time of corrosion. Conclusion The applications of corrosion inhibitor in the military aircraft maintenance as an effective means to prevent corrosion is valuable for populari-zation and application.%目的:验证海洋环境下硬膜水置换型缓蚀剂应用于军用飞机连接部位的有效性。方法采用功能渗透性试验、环境谱加速腐蚀对比试验对缓蚀剂性能进行评价,并通过在某型飞机典型结构部位的领先试用验证缓蚀剂的实际应用效果。结果缓蚀剂渗透率可达到85%。应用于军用飞机内部,对腐蚀的发展有明显的抑制作用,可显著延长腐蚀发生的时间。结论应用缓蚀剂作为腐蚀预防的有效手段,可在军用飞机维护中推广应用。

  9. Dynamic Steering for Improved Sensor Autonomy and Catalogue Maintenance

    Science.gov (United States)

    Hobson, T.; Gordon, N.; Clarkson, I.; Rutten, M.; Bessell, T.

    A number of international agencies endeavour to maintain catalogues of the man-made resident space objects (RSOs) currently orbiting the Earth. Such catalogues are primarily created to anticipate and avoid destructive collisions involving important space assets such as manned missions and active satellites. An agencys ability to achieve this objective is dependent on the accuracy, reliability and timeliness of the information used to update its catalogue. A primary means for gathering this information is by regularly making direct observations of the tens-of-thousands of currently detectable RSOs via networks of space surveillance sensors. But operational constraints sometimes prevent accurate and timely reacquisition of all known RSOs, which can cause them to become lost to the tracking system. Furthermore, when comprehensive acquisition of new objects does not occur, these objects, in addition to the lost RSOs, result in uncorrelated detections when next observed. Due to the rising number of space-missions and the introduction of newer, more capable space-sensors, the number of uncorrelated targets is at an all-time high. The process of differentiating uncorrelated detections caused by once-acquired now-lost RSOs from newly detected RSOs is a difficult and often labour intensive task. Current methods for overcoming this challenge focus on advancements in orbit propagation and object characterisation to improve prediction accuracy and target identification. In this paper, we describe a complementary approach that incorporates increased awareness of error and failed observations into the RSO tracking solution. Our methodology employs a technique called dynamic steering to improve the autonomy and capability of a space surveillance networks steerable sensors. By co-situating each sensor with a low-cost high-performance computer, the steerable sensor can quickly and intelligently decide how to steer itself. The sensor-system uses a dedicated parallel

  10. Research on gesture recognition of augmented reality maintenance guiding system based on improved SVM

    Science.gov (United States)

    Zhao, Shouwei; Zhang, Yong; Zhou, Bin; Ma, Dongxi

    2014-09-01

    Interaction is one of the key techniques of augmented reality (AR) maintenance guiding system. Because of the complexity of the maintenance guiding system's image background and the high dimensionality of gesture characteristics, the whole process of gesture recognition can be divided into three stages which are gesture segmentation, gesture characteristic feature modeling and trick recognition. In segmentation stage, for solving the misrecognition of skin-like region, a segmentation algorithm combing background mode and skin color to preclude some skin-like regions is adopted. In gesture characteristic feature modeling of image attributes stage, plenty of characteristic features are analyzed and acquired, such as structure characteristics, Hu invariant moments features and Fourier descriptor. In trick recognition stage, a classifier based on Support Vector Machine (SVM) is introduced into the augmented reality maintenance guiding process. SVM is a novel learning method based on statistical learning theory, processing academic foundation and excellent learning ability, having a lot of issues in machine learning area and special advantages in dealing with small samples, non-linear pattern recognition at high dimension. The gesture recognition of augmented reality maintenance guiding system is realized by SVM after the granulation of all the characteristic features. The experimental results of the simulation of number gesture recognition and its application in augmented reality maintenance guiding system show that the real-time performance and robustness of gesture recognition of AR maintenance guiding system can be greatly enhanced by improved SVM.

  11. Latent human error analysis and efficient improvement strategies by fuzzy TOPSIS in aviation maintenance tasks.

    Science.gov (United States)

    Chiu, Ming-Chuan; Hsieh, Min-Chih

    2016-05-01

    The purposes of this study were to develop a latent human error analysis process, to explore the factors of latent human error in aviation maintenance tasks, and to provide an efficient improvement strategy for addressing those errors. First, we used HFACS and RCA to define the error factors related to aviation maintenance tasks. Fuzzy TOPSIS with four criteria was applied to evaluate the error factors. Results show that 1) adverse physiological states, 2) physical/mental limitations, and 3) coordination, communication, and planning are the factors related to airline maintenance tasks that could be addressed easily and efficiently. This research establishes a new analytic process for investigating latent human error and provides a strategy for analyzing human error using fuzzy TOPSIS. Our analysis process complements shortages in existing methodologies by incorporating improvement efficiency, and it enhances the depth and broadness of human error analysis methodology.

  12. Global optimization for ducted coaxial-rotors aircraft based on Kriging model and improved particle swarm optimization algorithm

    Institute of Scientific and Technical Information of China (English)

    杨璐鸿; 刘顺安; 张冠宇; 王春雪

    2015-01-01

    To improve the operational efficiency of global optimization in engineering, Kriging model was established to simplify the mathematical model for calculations. Ducted coaxial-rotors aircraft was taken as an example and Fluent software was applied to the virtual prototype simulations. Through simulation sample points, the total lift of the ducted coaxial-rotors aircraft was obtained. The Kriging model was then constructed, and the function was fitted. Improved particle swarm optimization (PSO) was also utilized for the global optimization of the Kriging model of the ducted coaxial-rotors aircraft for the determination of optimized global coordinates. Finally, the optimized results were simulated by Fluent. The results show that the Kriging model and the improved PSO algorithm significantly improve the lift performance of ducted coaxial-rotors aircraft and computer operational efficiency.

  13. Effectiveness of Methadone Maintenance Therapy and Improvement in Quality of Life Following a Decade of Implementation.

    Science.gov (United States)

    Teoh Bing Fei, Joni; Yee, Anne; Habil, Mohamad Hussain Bin; Danaee, Mahmoud

    2016-10-01

    Methadone maintenance therapy has been found to be an effective harm reduction treatment for opioid use disorder. However evidence of its benefits over a longer duration of treatment is limited as most studies focus on its short term benefits. As methadone maintenance therapy reaches a decade since its implementation in Malaysia, this study sought to examine the effectiveness of methadone treatment, change in quality of life among patients since entry to methadone treatment, as well as factors predicting the magnitude of change in quality of life. This study found that methadone maintenance therapy was effective in reducing heroin use, injecting practices and crime, and in improving in social functioning and physical symptoms, but not in reducing sex-related HIV risk-taking behavior. Though patients had a significantly better quality of life at follow-up than at entry to methadone maintenance therapy, the improvement in quality of life was not significantly greater as the duration of treatment increased. Age above 50 years old, human immunodeficiency virus (HIV) positive status and physical symptoms predicted a poorer improvement in quality of life between baseline and follow-up. On the other hand, patients with hepatitis B showed a greater improvement in quality of life in the social relationships domain compared to patients without hepatitis B. In conclusion, methadone maintenance therapy is an effective treatment for opioid use disorder and improves quality of life but its benefits in further improving quality of life beyond a decade of treatment need further evaluation. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Impact of improved operation and maintenance on cohesive sediment transport in Gezira Scheme, Sudan

    NARCIS (Netherlands)

    Osman, I.S.E.

    2015-01-01

    Summary

    Efficient operation and maintenance of irrigation schemes are needed for improving the hydraulic performance of the canals, enhancing the crop yields and insuring sustainable production. There is a great need to enhance the researches and for a variety of tools such

  15. Impact of improved operation and maintenance on cohesive sediment transport in Gezira Scheme, Sudan

    NARCIS (Netherlands)

    Osman, I.S.E.

    2015-01-01

    Summary

    Efficient operation and maintenance of irrigation schemes are needed for improving the hydraulic performance of the canals, enhancing the crop yields and insuring sustainable production. There is a great need to enhance the researches and for a variety of tools such

  16. Improvement in renal function after everolimus introduction and calcineurin inhibitor reduction in maintenance thoracic transplant recipients

    DEFF Research Database (Denmark)

    Arora, Satish; Gude, Einar; Sigurdardottir, Vilborg

    2012-01-01

    The NOCTET (NOrdic Certican Trial in HEart and lung Transplantation) trial demonstrated that everolimus improves renal function in maintenance thoracic transplant (TTx) recipients. Nevertheless, introduction of everolimus is not recommended for patients with advanced renal failure. We evaluated...... NOCTET data to assess everolimus introduction amongst TTx recipients with advanced renal failure....

  17. Process Improvement at the Aircraft Intermediate Maintenance Detachment (AIMD) at Naval Air Station Whidbey Island

    Science.gov (United States)

    2006-12-01

    market for its products or services. It then develops a marketing mix —a particular combination of product, price, promotion, and place (i.e...significant impact on the makeup of this marketing mix , companies should develop strategies that take the unique nature of online marketing into... marketing mix is very important for companies, and the supply chain fits in there clearly. In other words, for most companies, place refers to the supply

  18. Quality Improvement Analysis of the Air Force Aircraft Maintenance and Munitions Officers Course

    Science.gov (United States)

    1994-09-01

    completely ignored the processes and conceptual aspects of the organizations which develop and operate training systems. Bryman (1989) points out that...the stakeholders of the system. Qualitative research can provide a perspective that many quantitative methodologies cannot ( Bryman , 1989: 139- 141...participant. 82nd Training Group, Sheppard AFB, TX. Personal communications, 10 August. Bryman , A. 1989. Research methods and organizational studies

  19. A multicriteria decision making approach applied to improving maintenance policies in healthcare organizations.

    Science.gov (United States)

    Carnero, María Carmen; Gómez, Andrés

    2016-04-23

    decision-making group. This approach is better suited to actual health care organization practice and depending on the subsystem analysed, improvements are introduced that are not included in normal maintenance policies; in this way, not only have different maintenance policies been suggested, but also alternatives that, in each case and according to viability, provide a more complete decision tool for the maintenance manager.

  20. 77 FR 67584 - Air Carrier Contract Maintenance Requirements

    Science.gov (United States)

    2012-11-13

    .... Williams, Aircraft Maintenance Division, Air Carrier Maintenance Branch, AFS-330, Federal Aviation... fulfill contracts with air carriers to perform their aircraft maintenance. The reasons for this shift are... a maintenance provider. Often, the maintenance provider may also work on a competitor's aircraft...

  1. Commander Naval Air Forces (CNAF) Aircraft Operations Maintenance (AOM): An Examination of Effectiveness in Maintaining and Operating an Aging Aircraft Fleet

    Science.gov (United States)

    2006-12-01

    By eliminating waste (muda), quality is improved, production time is reduced, and cost is reduced. Lean "tools" include CPI ( kaizen ), "pull...24 1. AIRSpeed ............................................................................................24 a. Lean ...THIS PAGE INTENTIONALLY LEFT BLANK xi LIST OF TABLES Table 1. Traditional Organization and Lean Organization

  2. A study of foreign object damage (FOD) and prevention method at the airport and aircraft maintenance area

    Science.gov (United States)

    Hussin, R.; Ismail, N.; Mustapa, S.

    2016-10-01

    Foreign object damage (FOD) is common risk for aviation industry since long time ago and it has contributed to many terrible incidents and fatalities. The cost of FOD cases every year is very high, which is around RM 1.2 billion. Therefore, a proper technique and strategy has to be taken by the designated organizations including airlines to further eliminate the FOD occurrences. It is not easy to control FOD due to some circumstances such as inappropriate working behaviour, poor working environment, insufficient technology and also disorganized housekeeping system. The main purpose of this research is to discuss and explain further about FOD and the techniques to prevent FOD. FOD is a universal concern in aviation industry and it is one of the reasons that contribute to aircraft failure and unwanted damages such as fatalities and causalities. Throughout this research, many information related to FOD problems and their impact on aviation industry are gathered and presented.

  3. Improvements to Software Maintenance Methods in Real Time Embedded Aviation Flight Systems.

    Science.gov (United States)

    1983-12-01

    69 FLI1GHT SOPTU&UE HISTORY The k-6 Intruder is in all weather, carrier based jet powered attack aircraft built by Grumman Aerospace Corporation , Long... Corporation of Long Beach, California shows a marked improvement in modularity with over one hundred identifiable modules. The situation seems to have...Applicationwar Mintenance, Communicatin 3. V5~i Mg Xti er’r12 n Yo-!i~y New York, Naval Weaon* (;enter, AV-8B Wea ons SystemSp t Facilit, A-i/A V-8 ;Facilit v

  4. Assimilating Aircraft-based measurements to improve the State of Distal Volcanic Ash Cloud

    Science.gov (United States)

    Fu, Guangliang; Lin, Hai Xiang; Heemink, Arnold; Segers, Arjo; Lu, Sha; Palsson, Thorgeir

    2015-04-01

    The sudden eruption at the 1666 m high, ice-capped Eyjafjallajökull volcano, in south Iceland during 14 April to 23 May 2010, had caused an unprecedented closure of the European and North Atlantic airspace resulting in global economic losses of US5 billion. This has initiated a lot of research on how to improve aviation advice after eruption onset. Good estimation of both the state of volcanic ash cloud and the emission of volcano are crucial for providing a successful aviation advice. Currently most of the approaches, employing satellite-based and ground-based measurements, are in the focus of improving the definition of Eruption Source Parameters (ESPs) such as plume height and mass eruption rate, which are certainly very important for estimating volcano emission and state of volcanic ash cloud near to the volcano. However, for ash cloud state in a far field, these approaches can hardly make improvements. This is mainly because the influence of ESPs on the ash plume becomes weaker as the distance to the volcano is getting farther, thus for a distal plume the information of ESPs will have little influence. This study aims to find an efficient way to improve the state of distal volcanic ash cloud. We use real-life aircraft-based observations, measured along Dutch border between Borken and Twist during the 2010 Eyjafjallajökull eruption, in an data assimilation system combining with a transport model to identify the potential benefit of this kind of observations and the influence on the ash state around Dutch border. We show that assimilating aircraft-based measurements can significantly improve the state of distal ash clouds, and further provide an improved aviation advice on distal ash plume. We compare the performances of different sequential data assimilation methods. The results show standard Ensemble Kalman Filter (EnKF) works better than others, which is because of the strong nonlinearity of the dynamics and the EnKF's resampling Gaussianity nature

  5. An Improved Distribution Policy with a Maintenance Aspect for an Urban Logistic Problem

    Directory of Open Access Journals (Sweden)

    Nadia Ndhaief

    2017-07-01

    Full Text Available In this paper, we present an improved distribution plan supporting an urban distribution center (UDC to solve the last mile problem of urban freight. This is motivated by the need of UDCs to satisfy daily demand in time under a high service level in allocated urban areas. Moreover, these demands could not be satisfied in individual cases because the delivery rate can be less than daily demand and/or affected by random failure or maintenance actions of vehicles. The scope of our work is to focus on a UDC, which needs to satisfy demands in a finite horizon. To that end, we consider a distribution policy on two sequential plans, a distribution plan correlated to a maintenance plan using a subcontracting strategy with several potential urban distribution centers (UDCs and performing preventive maintenance to ensure deliveries for their allocated urban area. The choice of subcontractor will depend on distance, environmental and availability criteria. In doing so, we define a mathematical model for searching the best distribution and maintenance plans using a subcontracting strategy. Moreover, we consider delay for the next periods with an expensive penalty. Finally, we present a numerical example illustrating the benefits of our approach.

  6. Direction of improvement of the radial-face seals of rotor supports of the aircraft engines

    Directory of Open Access Journals (Sweden)

    Petr Bondarchuk

    2014-10-01

    Full Text Available Today the radial-face contacts seals are the most wide-spread type of sealers of the aircraft engine rotor supports. In the paper the main shortcomings of the radial-face contact seals are specified the removal of which will result in increase in the operating range in terms of the pressure and temperature of the sealing air, reduction of leakages and extension of life-time. On the basis of the literature, patents and catalogues of the manufacturing companies the modern trends of improvement of the sealing structure are considered. The innovative technical solution for the radial-face contact seal with oil lubrication has been developed allowing increasing its efficiency. In order to increase the sealing reliability the hydrodynamic grooves of unique form made with the use of a laser are used. High sealing efficiency is ensured due to the simultaneous application of principles of hydrostatic and hydrodynamic lubrication. The method of calculation of seal properties has been suggested. The results of testing the new type of sealing for the engine rotor support as part of a moving-base simulator and aircraft gas-turbine engine have been presented.

  7. Approach of Improving the Inertial Navigation System Error for Large Transport Aircraft

    Institute of Scientific and Technical Information of China (English)

    WU Huzi; GENG Jianzhong; TANG Changhong; LI Wei

    2013-01-01

    The corresponding corrected method is proposed for the INS (INS-Inertial Navigation System) accumulated error of large transport aircraft.System errors contain aircraft position error,altitude error and speed error,one is increasing the accuracy of hardware; the other is development of low cost software algorithms.Because of improving hardware is more difficult in my country at present,developing software algorithms is essential way,which have been validated in my types of airplane.The combined heuristic algorithms (ABPNN,Advanced Back-propagation neural networks algorithm and LSM-least square method) are presented,which incorporates the effects of flight region and measured terrain height data by radar and barometer.Based on this algorithm,the appropriate match region was gotten by recognition of fiducial digital map in real time online.In process of work,the minimum of position error as a cost function and the constraint conditions are gave,the flight positions are recognized in real time and continuously,least sum of square is calculated based on LSM,in other words,the optimized result is obtained.The simulation case demonstrate that the method is very successful,the correct rate of recognition is more 90 percent.In words,the algorithm presented is economical,validation and effective.

  8. An Aircraft Navigation System Fault Diagnosis Method Based on Optimized Neural Network Algorithm

    Institute of Scientific and Technical Information of China (English)

    Jean-dedieu Weyepe

    2014-01-01

    Air data and inertial reference system (ADIRS) is one of the complex sub-system in the aircraft navigation system and it plays an important role into the flight safety of the aircraft. This paper propose an optimize neural network algorithm which is a combination of neural network and ant colony algorithm to improve efficiency of maintenance engineer job task.

  9. Toward Improved CFD Predictions of Slender Airframe Aerodynamics Using the F-16XL Aircraft (CAWAPI-2)

    Science.gov (United States)

    Luckring, James M.; Rizzi, Arthur; Davis, M. Bruce

    2014-01-01

    A coordinated project has been underway to improve CFD predictions of slender airframe aerodynamics. The work is focused on two flow conditions and leverages a unique flight data set obtained with an F-16XL aircraft. These conditions, a low-speed high angleof- attack case and a transonic low angle-of-attack case, were selected from a prior prediction campaign wherein the CFD failed to provide acceptable results. In this paper the background, objectives and approach to the current project are presented. The work embodies predictions from multiple numerical formulations that are contributed from multiple organizations, and the context of this campaign to other multi-code, multiorganizational efforts is included. The relevance of this body of work toward future supersonic commercial transport concepts is also briefly addressed.

  10. An improved filter-u least mean square vibration control algorithm for aircraft framework.

    Science.gov (United States)

    Huang, Quanzhen; Luo, Jun; Gao, Zhiyuan; Zhu, Xiaojin; Li, Hengyu

    2014-09-01

    Active vibration control of aerospace vehicle structures is very a hot spot and in which filter-u least mean square (FULMS) algorithm is one of the key methods. But for practical reasons and technical limitations, vibration reference signal extraction is always a difficult problem for FULMS algorithm. To solve the vibration reference signal extraction problem, an improved FULMS vibration control algorithm is proposed in this paper. Reference signal is constructed based on the controller structure and the data in the algorithm process, using a vibration response residual signal extracted directly from the vibration structure. To test the proposed algorithm, an aircraft frame model is built and an experimental platform is constructed. The simulation and experimental results show that the proposed algorithm is more practical with a good vibration suppression performance.

  11. Some improvements to the model of discrete sound field nearby multi-propeller aircraft

    Institute of Scientific and Technical Information of China (English)

    王同庆; 李晓东; 周盛

    1995-01-01

    Improvements to the mathematical-physical model of discrete sound field of multi-propeller aircraft have been made by using aeroacoustic analogy method, which considers the effects of fuselage boundary as well as the interference process of the multiple propeller sound field. The calculated results illustrate the effects of fuselage on the propeller sound field, the ’beating noise’ phenomenon and the principle of noise control of synchrophaser system. The model for boundaries with arbitrary shapes can also be used to calculate the effects of rigid boundaries in other harmonic sound fields. Results for sound scattering of a rigid sphere in a planar harmonic wave calculated by using this model are satisfactorily coincident with those by the analytical method.

  12. An improved filter-u least mean square vibration control algorithm for aircraft framework

    Science.gov (United States)

    Huang, Quanzhen; Luo, Jun; Gao, Zhiyuan; Zhu, Xiaojin; Li, Hengyu

    2014-09-01

    Active vibration control of aerospace vehicle structures is very a hot spot and in which filter-u least mean square (FULMS) algorithm is one of the key methods. But for practical reasons and technical limitations, vibration reference signal extraction is always a difficult problem for FULMS algorithm. To solve the vibration reference signal extraction problem, an improved FULMS vibration control algorithm is proposed in this paper. Reference signal is constructed based on the controller structure and the data in the algorithm process, using a vibration response residual signal extracted directly from the vibration structure. To test the proposed algorithm, an aircraft frame model is built and an experimental platform is constructed. The simulation and experimental results show that the proposed algorithm is more practical with a good vibration suppression performance.

  13. 14 CFR 43.7 - Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or...

    Science.gov (United States)

    2010-01-01

    ... FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE... holder of a repairman certificate (light-sport aircraft) with a maintenance rating may approve an... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Persons authorized to approve aircraft...

  14. Positioning embedded software maintenance within industrial maintenance

    OpenAIRE

    Karim, Ramin; Kajko-Mattsson, Mira; Söderholm, Peter; Candell, Olov; Tyrbern, Tommy; Öhlund, Hans; Johansson, Jan

    2008-01-01

    Little is known about of how software embedded in complex industrial technical systems is maintained. In this paper, we identify industrial maintenance process steps and position software maintenance activities within them. We do this in the context of JAS 39 Gripen, a multi-role combat aircraft developed by Saab.

  15. NIH working group report: Innovative research to improve maintenance of weight loss.

    Science.gov (United States)

    MacLean, Paul S; Wing, Rena R; Davidson, Terry; Epstein, Leonard; Goodpaster, Bret; Hall, Kevin D; Levin, Barry E; Perri, Michael G; Rolls, Barbara J; Rosenbaum, Michael; Rothman, Alexander J; Ryan, Donna

    2015-01-01

    The National Institutes of Health, led by the National Heart, Lung, and Blood Institute, organized a working group of experts to discuss the problem of weight regain after weight loss. A number of experts in integrative physiology and behavioral psychology were convened with the goal of merging their perspectives regarding the barriers to scientific progress and the development of novel ways to improve long-term outcomes in obesity therapeutics. The specific objectives of this working group were to: (1) identify the challenges that make maintaining a reduced weight so difficult; (2) review strategies that have been used to improve success in previous studies; and (3) recommend novel solutions that could be examined in future studies of long-term weight control. Specific barriers to successful weight loss maintenance include poor adherence to behavioral regimens and physiological adaptations that promote weight regain. A better understanding of how these behavioral and physiological barriers are related, how they vary between individuals, and how they can be overcome will lead to the development of novel strategies with improved outcomes. Greater collaboration and cross-talk between physiological and behavioral researchers is needed to advance the science and develop better strategies for weight loss maintenance. © 2014 The Obesity Society.

  16. 飞机维修保障信息系统权限管理设计与实现%Authority management design and realization of aircraft maintenance support information system

    Institute of Scientific and Technical Information of China (English)

    张珣; 李青; 杨志峰

    2014-01-01

    针对飞机一体化维修保障信息系统复杂的权限控制需求,在RBAC模型基础上引入了“组织”这一对象,提出了改进的权限控制模型,并通过业务逻辑将权限控制细化到具体的数据对象上,实现了细粒度的访问控制。利用该模型设计了权限管理子系统,给出了权限管理的具体实现,很好地满足了系统的权限控制需求。%Aiming at complex authority control requirements for integrated maintenance support information system of aircrafts , the object“organization”and improved model of authority control were introduced on the basis of RBAC ( Role-Based Access Control) model, and authority control are refined to specific data object by business logic, thus achieving fine-grained access control. Taking the advantage of this model, subsystem of authority management was designed and the authority management was concretely realized, well meeting the authority control requirements for the system.

  17. An improved particle filtering algorithm for aircraft engine gas-path fault diagnosis

    Directory of Open Access Journals (Sweden)

    Qihang Wang

    2016-07-01

    Full Text Available In this article, an improved particle filter with electromagnetism-like mechanism algorithm is proposed for aircraft engine gas-path component abrupt fault diagnosis. In order to avoid the particle degeneracy and sample impoverishment of normal particle filter, the electromagnetism-like mechanism optimization algorithm is introduced into resampling procedure, which adjusts the position of the particles through simulating attraction–repulsion mechanism between charged particles of the electromagnetism theory. The improved particle filter can solve the particle degradation problem and ensure the diversity of the particle set. Meanwhile, it enhances the ability of tracking abrupt fault due to considering the latest measurement information. Comparison of the proposed method with three different filter algorithms is carried out on a univariate nonstationary growth model. Simulations on a turbofan engine model indicate that compared to the normal particle filter, the improved particle filter can ensure the completion of the fault diagnosis within less sampling period and the root mean square error of parameters estimation is reduced.

  18. Improved Reliability-Based Optimization with Support Vector Machines and Its Application in Aircraft Wing Design

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2015-01-01

    Full Text Available A new reliability-based design optimization (RBDO method based on support vector machines (SVM and the Most Probable Point (MPP is proposed in this work. SVM is used to create a surrogate model of the limit-state function at the MPP with the gradient information in the reliability analysis. This guarantees that the surrogate model not only passes through the MPP but also is tangent to the limit-state function at the MPP. Then, importance sampling (IS is used to calculate the probability of failure based on the surrogate model. This treatment significantly improves the accuracy of reliability analysis. For RBDO, the Sequential Optimization and Reliability Assessment (SORA is employed as well, which decouples deterministic optimization from the reliability analysis. The improved SVM-based reliability analysis is used to amend the error from linear approximation for limit-state function in SORA. A mathematical example and a simplified aircraft wing design demonstrate that the improved SVM-based reliability analysis is more accurate than FORM and needs less training points than the Monte Carlo simulation and that the proposed optimization strategy is efficient.

  19. Maintenance and Energy Optimization of Lighting Systems for the Improvement of Historic Buildings: A Case Study

    Directory of Open Access Journals (Sweden)

    Ferdinando Salata

    2015-08-01

    Full Text Available Proper lighting is vital to improve, from an artistic point of view, the surface expanse and decorative detailing of architectural heritage buildings considered valuable. When properly lit, monumental buildings can become to onlookers an essential part of the city. Nowadays, for design planners dealing with the improvement of buildings, whose architectural design should be valorized, the real challenge is to combine the lighting artistic requirements with scrupulous economic management in order to limit the energy demand and to respect the environment. For these reasons, this case study examines the lighting of the monumental façade and the cloister of St. Peter in Chains situated in the Faculty of Engineering of Sapienza University of Rome. The present lighting installation, characterized by metal halides, compact fluorescent and halogen lamps, is compared with an alternative scenario presenting LED lamps and scenographic lighting of the monumental façade. Such comparison is based on the evaluation of the lighting levels for different visual tasks and on energy and maintenance issues; the first analysis was performed through the software DIALux Evo 4.0, whereas the second was performed using ecoCALC. This study leads to the conclusion that the lighting levels of the solution presenting LED lamps are better than those of the present solution, and they comply with current standards. Finally, the higher costs of LED lamp installations and the scenographic lighting of the monumental façade are balanced by lower maintenance costs, with a payback period of seven years.

  20. Repair, maintenance and improvement work in Finland; Korjausrakentaminen 2000-2010

    Energy Technology Data Exchange (ETDEWEB)

    Vainio, T.; Jaakkonen, L.; Nippala, E.; Lehtinen, E.; Isaksson, K. [VTT Building and Transport, Espoo (Finland)

    2002-07-01

    Repair, maintenance and improvement work in Finland - is basic research into how seriously the maintenance of the built environment is taken in Finland presently. The aim of the research has been to establish the value of today's renovation activity, its breakdown by building types, used renovation measures, and the reasons for renovations and the implementers. At the beginning of 2000, the combined floor area of the Finnish building stock was about 490 million square metres. Fifty-five percent of the total was housing stock: single-family houses, row houses, apartment blocks and free-time residential buildings. Households also owned 12 percent of the total building stock in the form of outbuildings and agricultural buildings. The remaining 33 percent consisted of industrial (15 %), commercial (12 %) and public buildings (8 %). In 2000, about euro 5,500 million was spent on renovating the building stock. The value of renovation has increased at a rate of 3-4 percent annually over the last ten years. Renovation's share of total building construction has been around 40 percent in recent years. The pace of renovation is going to decline slightly over the next ten years; annual growth will amount to 2.5-3.5 percent. Renovation on site, domestic production of building products used on site, and the many services related to the renovation process provided a total of 90,000 person-years of employment in 2000. Renovation decisions are often made by people who are not construction professionals whether a household in the case of a housing project or a property owner with regard to a non-residential project. Property managers have yet to realize the importance of preventive maintenance and repair. The tools (condition assessments and the maintenance manual) developed to assist building owners in long-term property management must be put to use. Renovation is a highly significant sector of construction and part of the national economy. It is important to allocate

  1. 14 CFR 91.1425 - CAMP: Maintenance, preventive maintenance, and alteration programs.

    Science.gov (United States)

    2010-01-01

    ... maintenance, and alteration programs. Each program manager who maintains program aircraft under a CAMP must..., preventive maintenance, or alterations; and (c) Each aircraft released to service is airworthy and has been... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false CAMP: Maintenance, preventive maintenance...

  2. Improving the Aircraft Design Process Using Web-Based Modeling and Simulation

    Science.gov (United States)

    Reed, John A.; Follen, Gregory J.; Afjeh, Abdollah A.; Follen, Gregory J. (Technical Monitor)

    2000-01-01

    Designing and developing new aircraft systems is time-consuming and expensive. Computational simulation is a promising means for reducing design cycle times, but requires a flexible software environment capable of integrating advanced multidisciplinary and multifidelity analysis methods, dynamically managing data across heterogeneous computing platforms, and distributing computationally complex tasks. Web-based simulation, with its emphasis on collaborative composition of simulation models, distributed heterogeneous execution, and dynamic multimedia documentation, has the potential to meet these requirements. This paper outlines the current aircraft design process, highlighting its problems and complexities, and presents our vision of an aircraft design process using Web-based modeling and simulation.

  3. Cost effectiveness and reliability improvement capabilities of CHECWORKS and SWIPS based inspection and maintenance plans

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S. [United Dynamics, Malvern, PA (United States); Borodotsky, A. [Rochester Gas and Electric Corp., NY (United States)

    1996-11-01

    CHECWORKS and SWIPS are computer programs that undertaken degradation analysis and generate prioritized lists for scheduling inspections. A simplified analysis presented in this paper demonstrates that application of such computer aided degeneration analysis and prioritized list based I and M plans can achieve full system reliability along with high cost effectiveness. For purposes of developing insight and a basic understanding, relative cost-effectiveness and system reliability improvement analysis is conducted on a small service water system for five types of inspection and maintenance plans. The following plans are considered: a full inspection plan, a random sampling plan, an experienced based sampling plan, a computer aided degeneration analysis based plan, and a superman based plan. The results obtained show that a computer aided inspection plan is the most effective of the feasible plans. For a realistic system, the plan can pay for the analysis cost and generate additional cost savings while maintaining full system reliability.

  4. CNS development of health maintenance programs: quality improvement and cost reduction.

    Science.gov (United States)

    Mullin, M H; Opperwall, B C; White, S L

    1995-01-01

    Several outpatient health maintenance programs were developed by CNSs that resulted in quality improvement and cost savings. Common implementation strategies, barriers to implementation, marketing issues and techniques, and revenue generation issues were found. An outpatient consultation model was used to expand enterostomal therapy and diabetic teaching services. Education and support programs include a cardiac support group and community education classes on aging. Preadmission programs include physical therapy consultation for patients scheduled for elective orthopedic surgery. Outpatient programs facilitate continuity of care in a managed care format, promote cost savings, and provide unique services that encourage patients to return to our hospital, thereby increasing market share. Key barriers encountered include inconsistent or ambiguous administrative support, budgetary constraints, lack of collaboration, communication problems, facility limitations, funding considerations, resource allocation, and territoriality. The programs are consistent with the change in focus of health care from treatment to prevention.

  5. Maintenance of quality of life improvements in diverse rural older adults.

    Science.gov (United States)

    Scogin, Forrest; Morthland, Martin; Kaufman, Allan; Chaplin, William; Kong, Grace

    2011-06-01

    The maintenance of effects from home-delivered cognitive-behavioral therapy (CBT) was examined. One hundred thirty-four participants, predominantly African American and primarily rural, low-resource, and physically frail, were randomly assigned to either immediate or delayed CBT. The six-month follow-up assessments indicated that among those who remained in the study, participants evidenced significantly improved quality of life and reductions in psychological symptoms at follow-up, relative to pretreatment levels. Posttreatment gains were maintained at follow-up. These data suggest that treatment effects can be achieved and perhaps maintained with a disadvantaged sample of older adults and suggest that evidence-based treatments delivered through nontraditional means can have effects beyond posttreatment. (c) 2011 APA, all rights reserved.

  6. Active Flow Control with Adaptive Design Techniques for Improved Aircraft Safety Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The increased aircraft safety potential of active flow control using synthetic jets - specifically, using synthetic jets on the leading edge of the wing to delay...

  7. 14 CFR 43.9 - Content, form, and disposition of maintenance, preventive maintenance, rebuilding, and alteration...

    Science.gov (United States)

    2010-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Content, form, and disposition of maintenance, preventive maintenance, rebuilding, and alteration records (except inspections performed...

  8. IMPROVEMENT OF OPERATIONAL CHARACTERISTICS OF THE AIRCRAFT WITH A DEFORMABLE COMBINED WING

    OpenAIRE

    Zinchenko, Dmytro; Ortamevzi, Gurkan

    2015-01-01

    In this article studied the characteristics of the experimental and numerical models, as well as a comparative analysis of performance of flying machines with different types of bearing surfaces with equal specific wing loading G / S.Development of experimental aircrafts with soft wings due to the need to increase the operation of  aircrafts.The results of wind tunnel test has performed using a general purpose classical scheme for models plane (Aeroprakt A-20) and are provided with two differ...

  9. An Aircraft Lifecycle Approach for the Cost-Benefit Analysis of Prognostics and Condition-Based Maintenance-Based on Discrete-Event Simulation

    Science.gov (United States)

    2014-10-02

    BC) influence airline revenues in the lifecycle CBA. The initial investment cost C0 is assumed as 50 Mio . US$ (aircraft list price in 2008 less an...Value Ticket price - EC [US$] 2008 111 Ticket price - BC [US$] 2008 334 Aircraft price C0 (incl. 35% discount) [ Mio . US$] 2008 50 Labor rate

  10. Final Report on the Operation and Maintenance Improvement Program for Concentrating Solar Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Cohen Gilbert E.; Kearney, David W.; Kolb, Gregory J.

    1999-06-01

    This report describes the results of a six-year, $6.3 million project to reduce operation and maintenance (O&M) costs at power plants employing concentrating solar power (CSP) technology. Sandia National Laboratories teamed with KJC Operating Company to implement the O&M Improvement Program. O&M technologies developed during the course of the program were demonstrated at the 150-MW Kramer Junction solar power park located in Boron, California. Improvements were made in the following areas: (a) efficiency of solar energy collection, (b) O&M information management, (c) reliability of solar field flow loop hardware, (d) plant operating strategy, and (e) cost reduction associated with environmental issues. A 37% reduction in annual O&M costs was achieved. Based on the lessons learned, an optimum solar- field O&M plan for future CSP plants is presented. Parabolic trough solar technology is employed at Kramer Junction. However, many of the O&M improvements described in the report are also applicable to CSP plants based on solar power tower or dish/engine concepts.

  11. Improvement of quality of life following 6 months of methadone maintenance therapy in Malaysia

    Directory of Open Access Journals (Sweden)

    Baharom Nizam

    2012-08-01

    Full Text Available Abstract Background Methadone Maintenance Therapy (MMT is one of the popular choices for drug substitution therapy and is fairly new in Malaysia. Aside from its role in harm reduction against HIV infection, MMT programme may potentially enhances clients’ quality of life. This study aims to identify the impact of MMT programme on clients’ quality of life after 6 months in treatment and to explore factors that may be associated with changes in their quality of life. Methods In this retrospective report review, 122 subjects from 2 government MMT clinics were selected from the district of Tampin, Negeri Sembilan, Malaysia. The raw score from the WHO Quality of Life questionnaire (WHOQOL-BREF, at baseline and 6 months after therapy were collected and converted to 0–100 scale form to give quality of life scores for four domains; physical, psychological, social relationships and environment. Other variables of interest were socio-demography, age when joining MMT programme, age and duration of illicit drug use, HIV and Hepatitis C status, and the Opiate Treatment Index (OTI score on drug use, sexual and social aspect at the baseline. Statistical analysis used the SPSS version 16. Results There was significant improvement in all four domains of quality of life, after 6 months of MMT. The largest improvement was for psychological domain (mean score difference 15.54 ± 20.81. Multivariable linear regression analysis showed that, for the physical domain, there was no significant predictor. For both the psychological and social domains, having tertiary education is a significant predictor for improvement in both aspects of quality of life. Negative HIV status is associated with improvement for the environment domain. Conclusions There was a significant short term improvement in the quality of life of MMT clients who stayed in the programme for at least 6 months in the district of Tampin, Negeri Sembilan, Malaysia.

  12. Statistical estimation of aircraft service conditions

    Directory of Open Access Journals (Sweden)

    Боузаієнне Меккі бен Салем

    2005-03-01

    Full Text Available  The question of an estimation of aircraft service conditions in airlines with use of statistical methods is considered at the analysis of maintenance programs of a aircrafts park to normative requirements.

  13. Maintenance practice of electrical power system for SR2X series aircraft%SR2X系列飞机电源系统的使用维护实践

    Institute of Scientific and Technical Information of China (English)

    杜光明; 王书伟

    2014-01-01

    SR2X系列飞机拥有复合材料结构和先进的空气动力学特性,蕴含了平面仪表板、多功能显示技术和极为出众的安全性革新,其中包括终极的保护手段--西锐机身降落伞系统(CAPS),为目前行业中最畅销的机型,有“空中宝马”之美誉。随着中国低空空域的逐步开放,将会有越来越多的SR2X系列飞机进入寻常百姓家,与之俱来的是飞机的使用与维护问题。从飞机使用维护的角度出发,介绍了SR2X系列飞机电源系统的组成及功用,结合电源系统工作原理,阐述了电源系统的使用及维护方法,并提出了存在的问题。%SR2X series aircraft with composite material structure have advanced aerodynamics characters. They also have flat dashboard,multi-function display technology and outstanding security innovations,which includes the ultimate protection means such as Cirrus Airframe Parachute System (CAPS) with great reputation of "air BMW" to be the best-selling models. With the gradual opening of China′s low-altitude airspace,more and more families could afford an SR2X series aircraft. So the use of aircraft and maintenance issues is following. Start from the maintenance of the aircraft,the composition and function of the power systems in SR2X series aircraft is introduced. In combination with the work principle of power systems,the usage and maintenance of the power system is elaborated,and some existing problems are also talked about.

  14. [Reference the YY/T 0841-2011 standard to improve preventive maintenance of medical electrical equipment and experience].

    Science.gov (United States)

    Liu, Xiang; Ge, Bin; Liu, Jinchu

    2014-09-01

    In this paper, we interpret the new YY/T 0841-2011 standard and contrast the difference between it and GB9706.1-2007 standard. Then, we improved the current preventive maintenance work. After the improvement, we not only have more effective detection of the electrical safety performance of all kinds of medical electrical equipment, but also reduce the workload of clinical engineers, improve efficiency, and reduce the risk of electrical shock.

  15. Optimum Wing Shape Determination of Highly Flexible Morphing Aircraft for Improved Flight Performance

    Science.gov (United States)

    Su, Weihua; Swei, Sean Shan-Min; Zhu, Guoming G.

    2016-01-01

    In this paper, optimum wing bending and torsion deformations are explored for a mission adaptive, highly flexible morphing aircraft. The complete highly flexible aircraft is modeled using a strain-based geometrically nonlinear beam formulation, coupled with unsteady aerodynamics and six-degrees-of-freedom rigid-body motions. Since there are no conventional discrete control surfaces for trimming the flexible aircraft, the design space for searching the optimum wing geometries is enlarged. To achieve high performance flight, the wing geometry is best tailored according to the specific flight mission needs. In this study, the steady level flight and the coordinated turn flight are considered, and the optimum wing deformations with the minimum drag at these flight conditions are searched by utilizing a modal-based optimization procedure, subject to the trim and other constraints. The numerical study verifies the feasibility of the modal-based optimization approach, and shows the resulting optimum wing configuration and its sensitivity under different flight profiles.

  16. A virtual reality intervention (Second Life) to improve weight maintenance: Rationale and design for an 18-month randomized trial.

    Science.gov (United States)

    Sullivan, D K; Goetz, J R; Gibson, C A; Mayo, M S; Washburn, R A; Lee, Y; Ptomey, L T; Donnelly, J E

    2016-01-01

    Despite the plethora of weight loss programs available in the US, the prevalence of overweight and obesity (BMI≥25kg/m(2)) among US adults continues to rise at least, in part, due to the high probability of weight regain following weight loss. Thus, the development and evaluation of novel interventions designed to improve weight maintenance are clearly needed. Virtual reality environments offer a promising platform for delivering weight maintenance interventions as they provide rapid feedback, learner experimentation, real-time personalized task selection and exploration. Utilizing virtual reality during weight maintenance allows individuals to engage in repeated experiential learning, practice skills, and participate in real-life scenarios without real-life repercussions, which may diminish weight regain. We will conduct an 18-month effectiveness trial (6 months weight loss, 12 months weight maintenance) in 202 overweight/obese adults (BMI 25-44.9kg/m(2)). Participants who achieve ≥5% weight loss following a 6month weight loss intervention delivered by phone conference call will be randomized to weight maintenance interventions delivered by conference call or conducted in a virtual environment (Second Life®). The primary aim of the study is to compare weight change during maintenance between the phone conference call and virtual groups. Secondarily, potential mediators of weight change including energy and macronutrient intake, physical activity, consumption of fruits and vegetables, self-efficacy for both physical activity and diet, and attendance and completion of experiential learning assignments will also be assessed.

  17. Improving Multi-Component Maintenance Acquisition with a Greedy Heuristic Local Algorithm

    Science.gov (United States)

    2013-04-01

    heuristic based on a genetic algorithm was applied in train maintenance scheduling problems by Sriskandarajah, Jardine , and Chan (1998), primarily...interdependent. OR Spectrum, 27(1), 63–84. Sriskandarajah, C., Jardine , A., & Chan, C. (1998). Maintenance scheduling of rolling stock using a genetic

  18. Improving work load and comfort of operators on modified hydraulic excavators in rail road maintenance

    NARCIS (Netherlands)

    Grinten, M.P. van der; Houtman, I.I.D.

    2000-01-01

    In small-scale projects of mechanized maintenance of rail roads special equipped hydraulic excavators (HE) are used in several maintenance tasks. One task concerns the exchange of the old crossbars and ballast under the rails by new materials (MCE-task). This task requires high precision of the HE-o

  19. Introducing artificial depth cues to improve task performance in ITER maintenance actions

    NARCIS (Netherlands)

    Heemskerk, C. J. M.; Eendebak, P. T.; Schropp, G. Y. R.; Hermes, H. V.; Elzendoorn, B. S. Q.; Magielsen, A. J.

    2013-01-01

    Maintenance operations on ITER tokamak components will be largely performed by remote handling. In previous work it was shown that representative maintenance tasks could be performed significantly faster with direct visual feedback than with camera feedback. In post-test interviews, operators indica

  20. Introducing artificial depth cues to improve task performance in ITER maintenance actions

    NARCIS (Netherlands)

    Heemskerk, C.J.M.; Eendebak, P.T.; Schropp, G.Y.R.; Hermes, H.V.; Elzendoorn, B.S.Q.; Magielsen, A.J.

    2013-01-01

    Maintenance operations on ITER tokamak components will be largely performed by remote handling. In previous work it was shown that representative maintenance tasks could be performed significantly faster with direct visual feedback than with camera feedback. In post-test interviews, operators indica

  1. Improving maintenance medication adherence in adult inflammatory bowel disease patients: a pilot study

    Directory of Open Access Journals (Sweden)

    Michelle L. Matteson-Kome

    2014-01-01

    Full Text Available Medication nonadherence in inflammatory bowel disease (IBD may lead to suboptimal control of the disease, decreased quality of life, and poor outcomes. This pilot study evaluated the feasibility, intervention mechanism, and potential effectiveness of a three-month continuous self-improvement (CSI intervention to enhance medication adherence (MA in adult nonadherent IBD patients. Adult IBD patients taking a daily or twice-daily dosed maintenance medication were screened electronically for two months to determine baseline MA levels. Nonadherent IBD participants were randomized to the CSI or the attention control (AC intervention and monitored for three months. The CSI intervention consisted of a data evaluation and system refinement process in which system changes were identified and implemented. The AC group was given educational information regarding IBD disease process, extra-intestinal manifestations of IBD, and medical therapy. Demographic statistics, change scores for within and between- group differences, and effect size estimates were calculated. Nine nonadherent participants (medication adherence score <0.85 were eligible for randomization. The intervention was found feasible and acceptable. Although no statistically significant improvement in MA was found (P=0.14, adherence improved in 3 of 4 of the CSI group and 1 of 2 in the attention control group. The effect size calculation of 1.9 will determine the sample size for future study. The results of this pilot study showed the intervention was feasible and had a positive effect on MA change score and adherence levels. A larger fully powered study is needed to test of the effectiveness of this innovative intervention.

  2. 41 CFR 102-33.170 - What standards must we establish or require (contractually, where applicable) for maintenance of...

    Science.gov (United States)

    2010-07-01

    ... establish or require (contractually, where applicable) for maintenance of our Government aircraft? 102-33... AIRCRAFT Managing Government Aircraft and Aircraft Parts Maintenance § 102-33.170 What standards must we establish or require (contractually, where applicable) for maintenance of our Government aircraft? For...

  3. More service of public utilities. Mobile data communication to improve maintenance services; Meer service. Mobiele datacommunicatie verbetert inzet onderhoudsdienst

    Energy Technology Data Exchange (ETDEWEB)

    Koenis, F.T.C. [KEMA Connect, Arnhem (Netherlands)

    2000-03-01

    Efficient data exchange between the energy company and its maintenance crew is important to be able to rapidly repair urgent failures. Wireless data communication can lead to cost reduction for the company, while at the same time the service to customers improves. 2 refs.

  4. Leveraging the test effect to improve maintenance of the gains achieved through cognitive rehabilitation.

    Science.gov (United States)

    Friedman, Rhonda B; Sullivan, Kelli L; Snider, Sarah F; Luta, George; Jones, Kevin T

    2017-02-01

    An important aspect of the rehabilitation of cognitive and linguistic function subsequent to brain injury is the maintenance of learning beyond the time of initial treatment. Such maintenance is often not satisfactorily achieved. Additional practice, or overtraining, may play a key role in long-term maintenance. In particular, the literature on learning in cognitively intact persons has suggested that it is testing, and not studying, that contributes to maintenance of learning. The present study investigates the hypothesis that continuing to test relearned words in persons with anomia will lead to significantly greater maintenance compared with continuing to study relearned words. The current study combines overtraining with the variable of test versus study in examining the effects of overtesting and overstudying on maintenance of word finding in 3 persons with aphasia. First, treatment successfully reestablished the connections between known items and their names. Once the connections were reestablished (i.e., items could be named successfully), each item was placed into 1 of 4 overtraining conditions: test and study, only test, only study, or no longer test or study. Maintenance was probed at 1 month and 4 months following the end of overtraining. The results are consistent with an advantage of testing compared with studying. All 3 participants showed significantly greater maintenance for words that were overtested than for words that were overstudied. This testing benefit persisted at 1 month and 4 months after completion of the treatment. In fact, there was no clear evidence for any benefit of overstudying. The present study demonstrates that overtesting, but not overstudying, leads to lasting maintenance of language rehabilitation gains in patients with anomia. The implications for the design of other treatment protocols are immense. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  5. Effects of genetic polymorphisms of CYP1A1, CYP2E1, GSTM1, and GSTT1 on the urinary levels of 1-hydroxypyrene and 2-naphthol in aircraft maintenance workers.

    Science.gov (United States)

    Lee, C Y; Lee, J Y; Kang, J W; Kim, H

    2001-09-15

    This study was undertaken to investigate the effects of genetic polymorphisms of the cytochrome P450 1A1 (CYP1A1) and 2E1 (CYP2E1), and glutathione S-transferases mu (GSTM1) and theta (GSTT1) on urinary 1-hydroxypyrene and 2-naphthol levels, and to estimate the level of exposure to polycyclic aromatic hydrocarbons (PAHs) in aircraft maintenance workers. In 218 Korean aircraft maintenance workers, the geometric means of urinary 1-hydroxypyrene and 2-naphthol were 0.32 and 3.25 micromol/mol creatinine, respectively. These urinary concentrations were approximately at the upper limit of the general population. Mean urinary 2-naphthol concentrations were significantly different between smokers and non-smokers. CYP1A1 and GSTM1 were statistically significant in analyses on both 1-hydroxypyrene and 2-naphthol levels among smokers. The results suggest that smoking has more profound effects on urinary PAH metabolites than does genetic polymorphisms in this population, and that CYP1A1 and GSTM1 activity might be related to the metabolism of 1-hydroxypyrene and 2-naphthol.

  6. Fleet Aviation Maintenance Organic Support (FAMOS) Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose:The Fleet Aviation Maintenance Organic Support (FAMOS) Laboratory at the Naval Air Warfare Center Aircraft Division, Lakehurst, NJ provides rapid engineering...

  7. Improving aircraft conceptual design - A PHIGS interactive graphics interface for ACSYNT

    Science.gov (United States)

    Wampler, S. G.; Myklebust, A.; Jayaram, S.; Gelhausen, P.

    1988-01-01

    A CAD interface has been created for the 'ACSYNT' aircraft conceptual design code that permits the execution and control of the design process via interactive graphics menus. This CAD interface was coded entirely with the new three-dimensional graphics standard, the Programmer's Hierarchical Interactive Graphics System. The CAD/ACSYNT system is designed for use by state-of-the-art high-speed imaging work stations. Attention is given to the approaches employed in modeling, data storage, and rendering.

  8. Sexual Dysfunction Improved in Heroin-Dependent Men after Methadone Maintenance Treatment in Tianjin, China

    Science.gov (United States)

    Zhang, Minying; Zhang, Huifang; Shi, Cynthia X.; McGoogan, Jennifer M.; Zhang, Baohua; Zhao, Linglong; Zhang, Mianzhi; Rou, Keming; Wu, Zunyou

    2014-01-01

    Objective To investigate whether methadone maintenance treatment (MMT) is correlated with sexual dysfunction in heroin-dependent men and to determine the prevalence and risk factors of sexual dysfunction among men on MMT. Methods The study included a retrospective survey and a cross-sectional survey which contained interviews of 293 men who are currently engaged in MMT. The results of the two surveys were compared. For a subset of 43 participants, radioimmunoassay was additionally conducted using retrospective and prospective blood samples to test the levels of plasma testosterone and luteinizing hormone. Other study evaluations were the International Index of Erectile Function (IIEF-15), and Self-rating Depression Scale. Results Sexual dysfunction in all five IIEF-15 domains (erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction) was strongly associated with long-term use of heroin. A decrease in the severity of sexual dysfunction was associated with MMT initiation. Erectile dysfunction, lack of sexual desire, inability to orgasm, and lack of intercourse satisfaction were significantly correlated with increasing age of the participants. Methadone dose and duration of methadone treatment were not found to be associated with sexual dysfunction. The level of plasma testosterone significantly declined during methadone treatment, but results from multivariate analysis indicated low levels of testosterone were not the main cause of sexual dysfunction. No correlation between reported depression status and sexual function was found. Conclusions While high levels of sexual dysfunction were reported by heroin-dependent men in our study before and after MMT initiation, MMT appears to be correlated with improved sexual function in the population of the study. PMID:24520361

  9. Sexual dysfunction improved in heroin-dependent men after methadone maintenance treatment in Tianjin, China.

    Directory of Open Access Journals (Sweden)

    Minying Zhang

    Full Text Available OBJECTIVE: To investigate whether methadone maintenance treatment (MMT is correlated with sexual dysfunction in heroin-dependent men and to determine the prevalence and risk factors of sexual dysfunction among men on MMT. METHODS: The study included a retrospective survey and a cross-sectional survey which contained interviews of 293 men who are currently engaged in MMT. The results of the two surveys were compared. For a subset of 43 participants, radioimmunoassay was additionally conducted using retrospective and prospective blood samples to test the levels of plasma testosterone and luteinizing hormone. Other study evaluations were the International Index of Erectile Function (IIEF-15, and Self-rating Depression Scale. RESULTS: Sexual dysfunction in all five IIEF-15 domains (erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction was strongly associated with long-term use of heroin. A decrease in the severity of sexual dysfunction was associated with MMT initiation. Erectile dysfunction, lack of sexual desire, inability to orgasm, and lack of intercourse satisfaction were significantly correlated with increasing age of the participants. Methadone dose and duration of methadone treatment were not found to be associated with sexual dysfunction. The level of plasma testosterone significantly declined during methadone treatment, but results from multivariate analysis indicated low levels of testosterone were not the main cause of sexual dysfunction. No correlation between reported depression status and sexual function was found. CONCLUSIONS: While high levels of sexual dysfunction were reported by heroin-dependent men in our study before and after MMT initiation, MMT appears to be correlated with improved sexual function in the population of the study.

  10. 14 CFR 135.433 - Maintenance and preventive maintenance training program.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintenance and preventive maintenance training program. 135.433 Section 135.433 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... SUCH AIRCRAFT Maintenance, Preventive Maintenance, and Alterations § 135.433 Maintenance and...

  11. The Earthscope Plate Boundary Observatory Alaska Region an Overview of Network Operation, Maintenance and Improvement

    Science.gov (United States)

    Enders, M.; Boyce, E. S.; Bierma, R.; Walker, K.; Feaux, K.

    2011-12-01

    UNAVCO has now completed its third year of operation of the 138 continuous GPS stations, 12 tiltmeters and 31 communications relays that comprise the Alaska Region of the Earthscope Plate Boundary Observatory. Working in Alaska has been challenging due to the extreme environmental conditions encountered and logistics difficulties. Despite these challenges we have been able to complete each summer field season with network operation at 95% or better. Throughout the last three years we have analyzed both our successes and failures to improve the quality of our network and better serve the scientific community. Additionally, we continue to evaluate and deploy new technologies to improve station reliability and add to the data set available from our stations. 2011 was a busy year for the Alaska engineering team and some highlights from last year's maintenance season include the following. This spring we completed testing and deployment of the first Inmarsat BGAN satellite terminal for data telemetry at AC60 Shemya Island. Shemya Island is at the far western end of the Aleutian Islands and is one of the most remote and difficult to access stations in the PBO AK network. Until the installation of the BGAN, this station was offline with no data telemetry for almost one year. Since the installation of the BGAN in early April 2011 dataflow has been uninterrupted. This year we also completed the first deployments of Stardot NetCamSC webcams in the PBO Network. Currently, these are installed and operational at six GPS stations in Alaska, with plans to install several more next season in Alaska. Images from these cameras can be found at the station homepages linked to from the UNAVCO website. In addition to the hard work put in by PBO engineers this year, it is important that we recognize the contributions of our partners. In particular the Alaska Volcano Observatory, the Alaska Earthquake Information Center and others who have provided us with valuable engineering assistance

  12. Environmental challenges improve resource utilization for asexual reproduction and maintenance in hydra.

    Science.gov (United States)

    Schaible, Ralf; Ringelhan, Felix; Kramer, Boris H; Miethe, Tanja

    2011-10-01

    Variation in life history can reflect genetic differences, and may be caused by environmental effects on phenotypes. Understanding how these two sources of life history variation interact to express an optimal allocation of resources in a changing environment is central to life history theory. This study addresses variation in the allocation of resources to asexual reproduction and to maintenance of Hydra magnipapillata in relation to differences in temperature and food availability. Hydra is a non-senescent, persistent species with primarily clonal reproduction. We recorded changes in budding rate and mean survival under starvation, which indicate changes in the allocation of resources to asexual reproduction and maintenance. In constant conditions we observed a clear trade-off between asexual reproduction and maintenance, where budding increased linearly with food intake while starvation survival stayed rather constant. In contrast, an environment with fluctuations in temperature or food availability promotes maintenance and increases the survival chances of hydra under starvation. Surprisingly, asexual reproduction also tends to be positively affected by fluctuating environmental conditions, which suggests that in this case there is no clear trade-off between asexual reproduction and maintenance in hydra. Environmental stresses have a beneficial impact on the fitness-related phenotypical traits of the basal metazoan hydra. The results indicate that, if the stress occurs in hormetic doses, variable stressful and fluctuating environments can be salutary for hydra. A closer examination of this dynamic can therefore enable us to develop a deeper understanding of the evolution of aging and longevity.

  13. Aircraft Environmental System Mechanic, 2-9. Block IV--Utility Systems and Flight Line Maintenance. Military Curriculum Materials for Vocational and Technical Education.

    Science.gov (United States)

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This publication contains a teaching guide and student instructional materials for conducting a high school or adult vocational education course to train persons to perform duties as an aircraft environmental systems mechanic. The instructional design for this course is self-paced and/or small group-paced. Instructor materials contained in the…

  14. A Literature Review of Code Clone Analysis to Improve Software Maintenance Process

    CERN Document Server

    Morshed, Md Monzur; Ahmed, Salah Uddin

    2012-01-01

    Software systems are getting more complex as the system grows where maintaining such system is a primary concern for the industry. Code clone is one of the factors making software maintenance more difficult. It is a process of replicating code blocks by copy-and-paste that is common in software development. In the beginning stage of the project, developers find it easy and time consuming though it has crucial drawbacks in the long run. There are two types of researchers where some researchers think clones lead to additional changes during maintenance phase, in later stage increase the overall maintenance effort. On the other hand, some researchers think that cloned codes are more stable than non cloned codes. In this study, we discussed Code Clones and different ideas, methods, clone detection tools, related research on code clone, case study.

  15. Effect of long intermittent hemodialysis on improving dialysis adequacy of maintenance hemodialysis patients

    Institute of Scientific and Technical Information of China (English)

    DAI Wen-di; ZHANG Dong-liang; CUI Wen-ying; LIU Wen-hu

    2013-01-01

    2 months after conversion to LIHD,and the PSQI score decreased from 10.80 to 5.45 and the ESS score decreased from 12.05 to 5.30 (P <0.01).However,sleep quality started to decline after 2 months on LIHD.QoL SF-36 score increased from 410.92 to 592.53 (P <0.01).Conclusion LIHD offers an effective improvement in dialysis adequacy for Chinese maintenance HD patients,but it improves sleep quality only briefly which may be related to loss of serum calcium and parathyroid dysfunction.

  16. Maintenance Therapy in Ovarian Cancer with Targeted Agents Improves PFS and OS: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Xinyu Qian

    Full Text Available Maintenance therapy with targeted agents for prolonging remission for ovarian cancer patients remains controversial. As a result, a meta-analysis was conducted to assess the effectiveness and safety of using maintenance therapy with targeted agents for the treatment of ovarian cancer.From inception to January 2015, we searched for randomized, controlled trials (RCTs using the following databases: PubMed, ScienceDirect, the Cochrane Library, Clinicaltrials.gov and EBSCO. Eligible trials included RCTs that evaluated standard chemotherapy which was either followed or not followed by targeted maintenance in patients with ovarian cancer who had been previously receiving adjunctive treatments, such as cytoreductive surgery and standard chemotherapy. The outcome measures included progression-free survival (PFS, overall survival (OS and incidence of adverse events.A total of 13 RCTs, which were published between 2006 and 2014, were found to be in accordance with our inclusion criteria. The primary meta-analysis indicated that both PFS and OS were statistically and significantly improved in the targeted maintenance therapy group as compared to the control group (PFS: HR = 0.84, 95%CI: 0.75 to 0.95, p = 0.001; OS: HR = 0.91, 95%CI: 0.84 to 0.98, p = 0.02. When taking safety into consideration, the use of targeted agents was significantly correlated with increased risks of fatigue, diarrhea, nausea, vomiting, and hypertension. However, no significant differences were found in incidence rates of abdominal pain, constipation or joint pain.Our results indicate that targeted maintenance therapy clearly improves the survival of ovarian cancer patients but may also increase the incidence of adverse events. Additional randomized, double-blind, placebo-controlled, multicenter investigations will be required on a larger cohort of patients to verify our findings.

  17. Control as a function of treasury maintenance of state budget of Ukraine: current state and directions of improvement

    Directory of Open Access Journals (Sweden)

    Наталія Іванівна Сушко

    2015-11-01

    Full Text Available It is analyzed the current control system of the Treasury bodies in the treasury maintenance process of state budget by revenue and expenditure. The control powers of Treasury bodies at the stage of activity estimation of the chief accountants of budget entities are considered. It is proposed the model of financial control that carried out by Treasury bodies. The directions of improvement of internal control, taking into account the best international practices, are defined

  18. Safety Forecast Model of Aircraft Maintenance Technicians Based on GA-BP Arithmetic%基于GA-BP算法的飞机维修人员安全预测模型

    Institute of Scientific and Technical Information of China (English)

    林嘉豪; 李克武; 刘楠; 张兵

    2012-01-01

    为实现对飞机维修人员安全性的有效预测,构建了维修人员安全性评价指标.通过专家打分法获得了维修人员安全性评价指标的原始训练数据和测试数据,分别采用BP-GDM模型、BP-LM模型和GA-BP-LM模型对数据进行了训练和预测,仿真结果表明:BP-GDM模型预测精度最差,且训练耗时较长,而GA-BP-LM模型不仅可以获得较高的预测精度,且耗时最短,BP-LM模型居中.此外GA-BP-LM模型相对误差值波动幅度最小,平均相对误差仅为3.33%,达到了预测的精度要求,为飞机维修人员安全性预测提供了有效手段.%In order to scientific predict the safety of the aircraft maintenance technicians, the safety evaluation index is established. Different kinds of aircraft maintenance technicians safety evaluation index originality training data and test data are gained by expert mark method, used the BP-GDM model, BP-LM model and GA-BP-LM model to train and predict, the simulation result show that: the forecast precision of BP-GDM model is the worst and consume lots of time, but GA-BP-LM gained the best forecast precision and the lest simulation time, the BP-LM was placed in the middle. What's more GA-BP-LM model had the smallest opposite error fluctuate, and the average opposite error value is only 3. 33%, which matched well with the expect requirement, the model provide effective method for predict of aircraft maintenance technicians safety.

  19. Meeting Air Transportation Demand in 2025 by Using Larger Aircraft and Alternative Routing to Complement NextGen Operational Improvements

    Science.gov (United States)

    Smith, Jeremy C.; Guerreiro, Nelson M.; Viken, Jeffrey K.; Dollyhigh, Samuel M.; Fenbert, James W.

    2010-01-01

    A study was performed that investigates the use of larger aircraft and alternative routing to complement the capacity benefits expected from the Next Generation Air Transportation System (NextGen) in 2025. National Airspace System (NAS) delays for the 2025 demand projected by the Transportation Systems Analysis Models (TSAM) were assessed using NASA s Airspace Concept Evaluation System (ACES). The shift in demand from commercial airline to automobile and from one airline route to another was investigated by adding the route delays determined from the ACES simulation to the travel times used in the TSAM and re-generating new flight scenarios. The ACES simulation results from this study determined that NextGen Operational Improvements alone do not provide sufficient airport capacity to meet the projected demand for passenger air travel in 2025 without significant system delays. Using larger aircraft with more seats on high-demand routes and introducing new direct routes, where demand warrants, significantly reduces delays, complementing NextGen improvements. Another significant finding of this study is that the adaptive behavior of passengers to avoid congested airline-routes is an important factor when projecting demand for transportation systems. Passengers will choose an alternative mode of transportation or alternative airline routes to avoid congested routes, thereby reducing delays to acceptable levels for the 2025 scenario; the penalty being that alternative routes and the option to drive increases overall trip time by 0.4% and may be less convenient than the first-choice route.

  20. Skeletal muscle structural lipids improve during weight-maintenance after a very low calorie dietary intervention

    DEFF Research Database (Denmark)

    Haugaard, Steen B; Vaag, Allan; Mu, Huiling

    2009-01-01

    BACKGROUND: The objective was to investigate in a group of obese subjects the course in skeletal muscle phospholipid (SMPL) fatty acids (FA) during a 24-weeks weight maintenance program, which was preceded by a successful very low calorie dietary intervention (VLCD). Special focus was addressed...

  1. Expanding Fixed-Wing Aircraft Capability in US Army Aviation Operations

    Science.gov (United States)

    2009-06-12

    Aircraft (FCA) program. Also in 2005, the Air Force expressed a need for a small airlifter and proposed development of the Light Cargo Aircraft ( LCA ...and LCA into the JCA program with the Army as program lead for both services. In 2007, the C-27J Spartan, a vastly improved version of the C-27A...limited by fuel consumption and maintenance readiness. The Stryker Brigade Combat Team (SBCT) is a lightly armored, motorized infantry brigade that

  2. 14 CFR 43.17 - Maintenance, preventive maintenance, and alterations performed on U.S. aeronautical products by...

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maintenance, preventive maintenance, and... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE, REBUILDING, AND ALTERATION § 43.17 Maintenance, preventive maintenance,...

  3. General Research on Advanced Maintenance Program Development for New Commercial Aircraft%浅析民用飞机先进维修计划的制订

    Institute of Scientific and Technical Information of China (English)

    徐志锋; 王勇; 那衡

    2011-01-01

    安全、可靠和经济性是制定维修计划的中心点,维修计划也是一切维修活动的指导性文件。面对民用航空产业竞争的加剧,航空公司已很难增加盈利水平,但却可以利用先进的维修计划有效降低维修成本,从而间接提高盈利水平。本文从MSG-3分析,直接维修成本(DMC)预估及技术支持角度,讲述了如何在设计过程中系统地为新型飞机制定先进的维修计划。%The development of maintenance program is primarily based on safety,reliability and economical efficiency,and it is also the guideline for all the maintenance activities.In the face of fierce competition,airlines have limited opportunity to increase their revenue.However,there is an opportunity to reduce costs through an advanced maintenance program for an indirect increase of the revenue.This article states the method about how to develop an advanced maintenance program systematically from the point of view of MSG-3 analysis,Direct Maintenance Cost(DMC) and technical support.

  4. An improved infrared carbon monoxide analyser for routine measurements aboard commercial airbus aircraft: Technical validation and first scientific results of the MOZAIC III programme

    Directory of Open Access Journals (Sweden)

    P. Nedelec

    2003-07-01

    Full Text Available The European-funded MOZAIC programme (Measurements of ozone and water vapour by Airbus in-service aircraft has been operational since 1994 aboard 5 commercial Airbus A340. It has gathered ozone and water vapour data between the ground and an altitude of 12 km from more than 20 000 long-range flights. A new infrared carbon monoxide analyser has been developed for installation on the MOZAIC equipped aircraft. Improvements in the basic characteristics of a commercial CO analysers have achieved performance suitable for routine aircraft measurements : ±5 ppbv, ±5% precision for a 30 s response time. The first year of operation on board 4 aircraft with more than 900 flights has proven the reliability and the usefulness of this CO analyser. The first scientific results are presented here, including UTLS exchange events and pollution within the boundary layer.

  5. Improving the turnaround maintenance of the Escravos gas plant / Ishekwene, I.V.

    OpenAIRE

    Ishekwene, Isaac Victor

    2011-01-01

    According to Oliver (2002) the success of turnaround maintenances is measured in terms of the cost of completion, time, safety performance and the performance of the plant afterwards. The Escravos gas plant (EGP) is a gas processing plant that converts associated gas from Chevron owned crude oil wells to liquefied petroleum gas, natural gas and gas condensate (Chevron intranet. Website assessed on September 14, 2007). According to the EGP plant operations coordinator (See inter...

  6. A Case Analysis to Improve the Application Maintenance and Support Outsourcing of a National Airline

    OpenAIRE

    Chew, Alice

    2009-01-01

    The reliance on outsourcing as a means of providing IT services has been growing steadily over the past decade. There have been numerous academic articles dedicated to IT outsourcing in general. This research seeks to fill the gap by providing insights to a less explored scope of IT activity outsourced - application maintenance and support (AMS); specifically, the post-contract management of AMS outsourcing. It is during this building block of management that success is ultimately determined...

  7. An improved MCDM method for maintenance approach selection: A case study of auto industry

    Directory of Open Access Journals (Sweden)

    Milad Aghaee

    2012-01-01

    Full Text Available In the current competitive environment, managers have been making attempts to convert organizations under their supervision into competitive and responsive through creating capability of timely delivery of quality products and services. In line with this, maintenance as a system plays an important role in achieving these goals. The maintenance strategy selection is a kind of multiple criteria decision-making (MCDM problem, which requires considering a large number of complex factors as multiple evaluation criteria. A robust MCDM method should consider the interactions among criteria. The analytic network process (ANP is a relatively new MCDM method, which can deal with all kinds of interactions systematically. Moreover, the Decision Making Trial and Evaluation Laboratory (DEMATEL not only can convert the relations between cause and effect of criteria into a visual structural model, but also can be used as a way to handle the inner dependences within a set of criteria. Hence, this paper proposes an effective solution based on a combined ANP and DEMATEL approach to help vehicle companies that need to evaluate and select maintenance strategies.

  8. Guidance for the design and management of a maintenance plan to assure safety and improve the predictability of a DOE nuclear irradiation facility. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Booth, R.S.; Kryter, R.C.; Shepard, R.L.; Smith, O.L. [Oak Ridge National Lab., TN (United States); Upadhyaya, B.R. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Nuclear Engineering; Rowan, W.J.

    1994-10-01

    A program is recommended for planning the maintenance of DOE nuclear facilities that will help safety and enhance availability throughout a facility`s life cycle. While investigating the requirements for maintenance activities, a major difference was identified between the strategy suitable for a conventional power reactor and one for a research reactor facility: the latter should provide a high degree of predicted availability (referred to hereafter as ``predictability``) to its users, whereas the former should maximize total energy production. These differing operating goals necessitate different maintenance strategies. A strategy for scheduling research reactor facility operation and shutdown for maintenance must balance safety, reliability,and predicted availability. The approach developed here is based on three major elements: (1) a probabilistic risk analysis of the balance between assured reliability and predictability (presented in Appendix C), (2) an assessment of the safety and operational impact of maintenance activities applied to various components of the facility, and (3) a data base of historical and operational information on the performance and requirements for maintenance of various components. These factors are integrated into a set of guidelines for designing a new highly maintainable facility, for preparing flexible schedules for improved maintenance of existing facilities, and for anticipating the maintenance required to extend the life of an aging facility. Although tailored to research reactor facilities, the methodology has broader applicability and may therefore be used to improved the maintenance of power reactors, particularly in anticipation of peak load demands.

  9. Qualitative analysis of maintenance and services carried out in a repair plant on the example of a multi-purpose aircraft

    Directory of Open Access Journals (Sweden)

    Woźny Piotr

    2015-12-01

    Full Text Available The article presents revealed failures and damages of the multi-task aircraft (ACFT reported by users to the service organization, aimed at assessing and removing them. In the course of the analysis process, damages and malfunctions were grouped, depending on aviation specialities. A review was conducted that targeted occurring malfunctions and damages in a set of ACFT of the same type, over a twelve-year operational period. In the assessed period, trend lines were determined, showing a drop in the number of accepted claims submitted by ACFT users.

  10. Elastically Shaped Wing Optimization and Aircraft Concept for Improved Cruise Efficiency

    Science.gov (United States)

    Nguyen, Nhan; Trinh, Khanh; Reynolds, Kevin; Kless, James; Aftosmis, Michael; Urnes, James, Sr.; Ippolito, Corey

    2013-01-01

    This paper presents the findings of a study conducted tn 2010 by the NASA Innovation Fund Award project entitled "Elastically Shaped Future Air Vehicle Concept". The study presents three themes in support of meeting national and global aviation challenges of reducing fuel burn for present and future aviation systems. The first theme addresses the drag reduction goal through innovative vehicle configurations via non-planar wing optimization. Two wing candidate concepts have been identified from the wing optimization: a drooped wing shape and an inflected wing shape. The drooped wing shape is a truly biologically inspired wing concept that mimics a seagull wing and could achieve about 5% to 6% drag reduction, which is aerodynamically significant. From a practical perspective, this concept would require new radical changes to the current aircraft development capabilities for new vehicles with futuristic-looking wings such as this concept. The inflected wing concepts could achieve between 3% to 4% drag reduction. While the drag reduction benefit may be less, the inflected-wing concept could have a near-term impact since this concept could be developed within the current aircraft development capabilities. The second theme addresses the drag reduction goal through a new concept of elastic wing shaping control. By aeroelastically tailoring the wing shape with active control to maintain optimal aerodynamics, a significant drag reduction benefit could be realized. A significant reduction in fuel burn for long-range cruise from elastic wing shaping control could be realized. To realize the potential of the elastic wing shaping control concept, the third theme emerges that addresses the drag reduction goal through a new aerodynamic control effector called a variable camber continuous trailing edge flap. Conventional aerodynamic control surfaces are discrete independent surfaces that cause geometric discontinuities at the trailing edge region. These discontinuities promote

  11. Dynamic optimization of maintenance and improvement planning for water main system: Periodic replacement approach

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Woo; Choi, Go Bong; Lee, Jong Min [Seoul National University, Seoul (Korea, Republic of); Suh, Jung Chul [Samchully Corporation, Seoul (Korea, Republic of)

    2016-01-15

    This paper proposes a Markov decision process (MDP) based approach to derive an optimal schedule of maintenance, rehabilitation and replacement of the water main system. The scheduling problem utilizes auxiliary information of a pipe such as the current state, cost, and deterioration model. The objective function and detailed algorithm of dynamic programming are modified to solve the periodic replacement problem. The optimal policy evaluated by the proposed algorithm is compared to several existing policies via Monte Carlo simulations. The proposed decision framework provides a systematic way to obtain an optimal policy.

  12. Remote Expertise for Maintenance: An Application of Telecommunications Technology to Improve Shipboard Equipment Readiness

    Science.gov (United States)

    1984-10-01

    34°’’ ’^^"^-^ ’’’’’ shore-based’ ; xpert maintLa’nce tec’niSnf de?p ^in. th^’^ M ^^l" ■’■^"’°’^ ’’’^ troubleshooting; and (3) conducting studies to 1,1...Survey Respondents 7 2. Applicability Scores for Telecommunications Accessory Devices Within and Across Categories of Equipment Components...maintenance personnel. The two telecommunications linkage configurations tested in this study were audio plus video and audio with video as needed

  13. TIGER -- A technology to improve the delivery capability of nuclear bombs and the survivability of the delivery aircraft

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-12-31

    The TIGER (Terminal guided and Extended-Range) Program was initiated in 1972 to study improved delivery capabilities for stockpiled tactical nuclear bombs. The Southeast Asia conflict fostered the development of air-delivered standoff conventional weapons utilizing terminal guidance systems. SNL initiated the TIGER program to determine if current nuclear bombs could be provided with a similarly accurate standoff capabilities. These conventional weapon delivery techniques, while allowing highly accurate attack, generally require entering the target area at high altitude to establish line of sight to the target. In parallel with the TIGER program, system studies analyzed this concept and showed marked improvement in aircraft and weapon survivability with moderate standoff (10--20 km) if low level deliveries (60 m) could be accomplished. As a result of this work, the TIGER program was redirected in early 1974 to demonstrate a standoff bomb with good accuracy (90 m CEP) when delivered from low flying aircraft. This program redirection resulted in the selection of an inertial guidance system to replace the earlier terminal guidance systems. This program was called the Extended-Range Bomb (ERB). In May 1974, a joint Air Force/DOE study identified the desirability of having a single tactical weapon which could be employed against either fixed, preselected targets, or mobile battlefield targets. Studies conducted on the ERB system showed that the inertially guided weapon could fly not only the standoff mission but also a return-to-target mission against the mobile battlefield targets whose locations are not known accurately enough to use a standoff delivery. The ERB program evolved from these initial investigations into an exploratory program to develop the hardware and demonstrate the technology required to fly standoff and return-to-target trajectories. The application of this technology in the form of field retrofit kits to the B61 bomb is called TIGER II.

  14. TIGER -- A technology to improve the delivery capability of nuclear bombs and the survivability of the delivery aircraft

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-12-31

    The TIGER (Terminal guided and Extended-Range) Program was initiated in 1972 to study improved delivery capabilities for stockpiled tactical nuclear bombs. The Southeast Asia conflict fostered the development of air-delivered standoff conventional weapons utilizing terminal guidance systems. SNL initiated the TIGER program to determine if current nuclear bombs could be provided with a similarly accurate standoff capabilities. These conventional weapon delivery techniques, while allowing highly accurate attack, generally require entering the target area at high altitude to establish line of sight to the target. In parallel with the TIGER program, system studies analyzed this concept and showed marked improvement in aircraft and weapon survivability with moderate standoff (10--20 km) if low level deliveries (60 m) could be accomplished. As a result of this work, the TIGER program was redirected in early 1974 to demonstrate a standoff bomb with good accuracy (90 m CEP) when delivered from low flying aircraft. This program redirection resulted in the selection of an inertial guidance system to replace the earlier terminal guidance systems. This program was called the Extended-Range Bomb (ERB). In May 1974, a joint Air Force/DOE study identified the desirability of having a single tactical weapon which could be employed against either fixed, preselected targets, or mobile battlefield targets. Studies conducted on the ERB system showed that the inertially guided weapon could fly not only the standoff mission but also a return-to-target mission against the mobile battlefield targets whose locations are not known accurately enough to use a standoff delivery. The ERB program evolved from these initial investigations into an exploratory program to develop the hardware and demonstrate the technology required to fly standoff and return-to-target trajectories. The application of this technology in the form of field retrofit kits to the B61 bomb is called TIGER II.

  15. Progress in Space Weather Modeling and Observations Needed to Improve the Operational NAIRAS Model Aircraft Radiation Exposure Predictions

    Science.gov (United States)

    Mertens, C. J.; Kress, B. T.; Wiltberger, M. J.; Tobiska, W.; Xu, X.

    2011-12-01

    The Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) is a prototype operational model for predicting commercial aircraft radiation exposure from galactic and solar cosmic rays. NAIRAS predictions are currently streaming live from the project's public website, and the exposure rate nowcast is also available on the SpaceWx smartphone app for iPhone, IPad, and Android. Cosmic rays are the primary source of human exposure to high linear energy transfer radiation at aircraft altitudes, which increases the risk of cancer and other adverse health effects. Thus, the NAIRAS model addresses an important national need with broad societal, public health and economic benefits. The processes responsible for the variability in the solar wind, interplanetary magnetic field, solar energetic particle spectrum, and the dynamical response of the magnetosphere to these space environment inputs, strongly influence the composition and energy distribution of the atmospheric ionizing radiation field. During the development of the NAIRAS model, new science questions were identified that must be addressed in order to obtain a more reliable and robust operational model of atmospheric radiation exposure. Addressing these science questions require improvements in both space weather modeling and observations. The focus of this talk is to present these science questions, the proposed methodologies for addressing these science questions, and the anticipated improvements to the operational predictions of atmospheric radiation exposure. The overarching goal of this work is to provide a decision support tool for the aviation industry that will enable an optimal balance to be achieved between minimizing health risks to passengers and aircrew while simultaneously minimizing costs to the airline companies.

  16. Skeletal muscle structural lipids improve during weight-maintenance after a very low calorie dietary intervention

    Directory of Open Access Journals (Sweden)

    Vaag Allan

    2009-08-01

    Full Text Available Abstract Background The objective was to investigate in a group of obese subjects the course in skeletal muscle phospholipid (SMPL fatty acids (FA during a 24-weeks weight maintenance program, which was preceded by a successful very low calorie dietary intervention (VLCD. Special focus was addressed to SMPL omega-3 FA, which is a lipid entity that influences insulin action. Methods Nine obese subjects (BMI = 35.7 ± 1.0 kg/m2, who had completed an 8 weeks VLCD (weight-loss = -9.7 ± 1.6 kg, P Results HOMA-IR and HbA1c stabilized and SMPL total omega-3 FA, docosahexaenoic acid and ratio of n-3/n-6 polyunsaturated FA increased by 24% (P Conclusion The data are consistent with the notion that greater SMPL omega-3 FA obtained during a weight-maintenance program may play a role for preserving insulin sensitivity and glycemic control being generated during a preceding VLCD.

  17. 14 CFR 135.425 - Maintenance, preventive maintenance, and alteration programs.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintenance, preventive maintenance, and alteration programs. 135.425 Section 135.425 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... ON BOARD SUCH AIRCRAFT Maintenance, Preventive Maintenance, and Alterations § 135.425...

  18. 14 CFR 135.437 - Authority to perform and approve maintenance, preventive maintenance, and alterations.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Authority to perform and approve maintenance, preventive maintenance, and alterations. 135.437 Section 135.437 Aeronautics and Space FEDERAL... AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Maintenance, Preventive Maintenance,...

  19. 14 CFR 135.423 - Maintenance, preventive maintenance, and alteration organization.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintenance, preventive maintenance, and alteration organization. 135.423 Section 135.423 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... ON BOARD SUCH AIRCRAFT Maintenance, Preventive Maintenance, and Alterations § 135.423...

  20. 14 CFR 43.3 - Persons authorized to perform maintenance, preventive maintenance, rebuilding, and alterations.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Persons authorized to perform maintenance, preventive maintenance, rebuilding, and alterations. 43.3 Section 43.3 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE, REBUILDING,...

  1. Validation Effectiveness of Develop Maintainability Allocation on Aircraft Mechanical Components

    Directory of Open Access Journals (Sweden)

    Wan Husain W.M.S.

    2016-01-01

    Full Text Available Maintainability Allocation is a process to identify the allowable maximum task time for each individual component. Consequently, this provides clear pictures to the designers to design and identify potential design improvement within allowable maintenance allocation time limits. During the design process elements such as missteps or misapplications most commonly occur. Here, the authors propose having the maximum target for each individual maintainability component. The main objective of this paper is to present the validation process of developed Maintainability Allocation to potentially eliminate previous problems. The process of validation begins with analysed all the data collected from Service Difficulty Reports (SDR for selected aircraft. This is to understand the problems from existing aircraft before a new design is proposed through the process of Maintainability Allocation prediction. The validation processes have discovered the importance of utilising historical information such as feedback information. The second area is looking at the element of quantifying the data collected from aircraft feedback information which contains various types of information that could be used for future improvement. Validation process shows that feedback information has helped to identify the critical and sensitive components that need more attention for further improvement. The study shows that the aircraft maintenance related feedback information systems analyses were very useful for deciding maintainability effectiveness; these include planning, organising maintenance and design improvement. There is no doubt that feedback information has the ability to contribute an important role in design activities. The results also show that maintainability is an important measure that can be used as a guideline for managing efforts made for the improvement of aircraft components.

  2. Integrating Satellite, Aircraft, and Ground-Based Observations to Improve a GHG Inventory Network

    Science.gov (United States)

    Midzik, M.; Abbate, J.; Raheja, G.

    2016-12-01

    Methane (CH4) is the second-most effective greenhouse gas, with a global warming potential up to 70 times that of carbon dioxide (CO2) over the span of 25 years. With a majority of these emissions attributed to livestock, landfill, and wastewater treatment, CH4 emissions are a concern for both urban and rural landscapes. Though Earth-observing satellites can effectively monitor mid-to-upper tropospheric CH4 on a global scale, current instrumentation is limited in its capacity to accurately measure near-surface CH4 on a local scale. The Bay Area Air Quality Management District (BAAQMD) regulates stationary sources of air pollution in the nine counties surrounding San Francisco Bay. BAAQMD traditionally estimates emissions using a bottom-up approach, combining emissions factor and activity data to estimate source emissions per sector. However, recent literature suggests that these bottom-up approaches are underestimating CH4 emissions by nearly 50% in many regions of California. In efforts to address the discrepancy, this project compares BAAQMD's current CH4 spatial emissions inventory with top-down sub-Planetary Boundary Layer aircraft measurements from the NASA Alpha Jet Atmospheric eXperiment (AJAX). Together, these different approaches were used to identify CH4 hot-spots in the San Francisco Bay Area. In addition, sources of high-CH4 anomalies were identified using USGS high resolution aerial imagery and trajectory analysis. Furthermore, this project used NASA Landsat 8 imagery and USGS orthoimagery to classify the types of indicated emissions and infer other points of interest not included in the current BAAQMD inventory. These findings help pinpoint specific sites for BAAQMD's upcoming Mobile GHG Measurement Network; furthermore, results from this project suggest future sites for coincident data collection between advancing bottom-up and top-down instruments.

  3. Tropical cyclones-Pacific Asian Research Campaign for Improvement of Intensity estimations/forecasts (T-PARCII): A research plan of typhoon aircraft observations in Japan

    Science.gov (United States)

    Tsuboki, Kazuhisa

    2017-04-01

    Typhoons are the most devastating weather system occurring in the western North Pacific and the South China Sea. Violent wind and heavy rainfall associated with a typhoon cause huge disaster in East Asia including Japan. In 2013, Supertyphoon Haiyan struck the Philippines caused a very high storm surge and more than 7000 people were killed. In 2015, two typhoons approached the main islands of Japan and severe flood occurred in the northern Kanto region. Typhoons are still the largest cause of natural disaster in East Asia. Moreover, many researches have projected increase of typhoon intensity with the climate change. This suggests that a typhoon risk is increasing in East Asia. However, the historical data of typhoon include large uncertainty. In particular, intensity data of the most intense typhoon category have larger error after the US aircraft reconnaissance of typhoon was terminated in 1987.The main objective of the present study is improvements of typhoon intensity estimations and of forecasts of intensity and track. We will perform aircraft observation of typhoon and the observed data are assimilated to numerical models to improve intensity estimation. Using radars and balloons, observations of thermodynamical and cloud-microphysical processes of typhoons will be also performed to improve physical processes of numerical model. In typhoon seasons (mostly in August and September), we will perform aircraft observations of typhoons. Using dropsondes from the aircraft, temperature, humidity, pressure, and wind are measured in surroundings of the typhoon inner core region. The dropsonde data are assimilated to a cloud-resolving model which has been developed in Nagoya University and named the Cloud Resolving Storm Simulator (CReSS). Then, more accurate estimations and forecasts of the typhoon intensity will be made as well as typhoon tracks. Furthermore, we will utilize a ground-based balloon with microscope camera, X-band precipitation radar, Ka-band cloud radar

  4. Improving imaging utilization through practice quality improvement (maintenance of certification part IV): a review of requirements and approach to implementation.

    Science.gov (United States)

    Griffith, Brent; Brown, Manuel L; Jain, Rajan

    2014-04-01

    The purposes of this article are to review the American Board of Radiology requirements for practice quality improvement and to describe our approach to improving imaging utilization while offering a guide to implementing similar projects at other institutions, emphasizing the plan-do-study-act approach. There is increased emphasis on improving quality in health care. Our institution has undertaken a multiphase practice quality improvement project addressing the appropriate utilization of screening cervical spinal CT in an emergency department.

  5. Using Data Envelopment Analysis to Evaluate Technical Training Program for Maintenance Units

    Directory of Open Access Journals (Sweden)

    Nai-Chieh Wei and Shui-Cheung Cham

    2015-05-01

    Full Text Available Applying data envelope analysis (DEA, this study focuses on the influences of objectivity and subjectivity on aircraft maintenance supervision evaluation and inspection procedure; the aim is to improve overall logistic operation and training efficiency. Moreover, the results of this analysis will be helpful for making decisions in training, management, capability and competitiveness

  6. Current and future inspection and maintenance challenges

    Science.gov (United States)

    Bhagat, Pramode K.; Bessette, Lorence; Leonelli, Fredrick

    1996-11-01

    Ever-increasing diversity of civilian aircraft inventory and continued technological advancements in aircraft materials, aircraft flight control equipment, testing equipment, and software methodologies are impacting aircraft inspection and maintenance practices. Current procedures deal mainly with issues related to structural and electrical or electronic integrity to assure continued airworthiness of operational aircraft. Techniques and methodologies for these are widely available, and training needs are well defined. Advances in technology, however, are yielding new and different aircraft, which require more sophisticated electronic instruments for navigation and control.A major issue is the continued reliability and airworthiness of avionics and development of adequate safeguards for these aircraft. Built-in test equipment, maintenance across terminals, and data bases defining inspection needs that are based on operational data, and software integrity, are also rapidly becoming important considerations in aircraft maintenance. In this era of declining funds and personnel resources, a cost-effective approach requires a fresh look at all phases of the current inspection and maintenance practices, including oversight and management. This paper provides a perspective on issues and challenges facing a civilian regulatory agency, specifically, the aircraft maintenance division in the FAA.

  7. Personnel Quality Evaluation of Aircraft Maintenance Equipment Based on BP Neural Network%基于BP神经网络的飞机装备维护人员综合素质评估

    Institute of Scientific and Technical Information of China (English)

    陈丽娟; 余隋怀; 初建杰; 卢慧颖

    2011-01-01

    在分析了影响维护人员素质的因素后提出了基于BP神经网络对维护人员综合素质进行评估的方法.利用BP神经网络建立了维护人员综合素质的评价模型,并通过使用改进算法进行了训练.训练测试的结果表明,该方法具有较高的可行性和有效性,为全面评估维护人员的素质提供了一种方法.%The factors that affect the equipment maintenance personnel are comprehensively analyzed, and a method is proposed to evaluate comprehensive quality of equipment maintenance personnel based on BP neural network.Evaluation model of equipment maintenance personnel is established by using BP neural network, and the improved algorithm is used for training.Training test results show that this method has a high feasibility and effectiveness, and provides a way to assess the quality of equipment maintenance personnel comprehensively.

  8. Corrosion Protection and Design Improvement of an Aircraft%某型飞机腐蚀防护及设计改进

    Institute of Scientific and Technical Information of China (English)

    彭志军; 王学强; 叶彬

    2014-01-01

    Objective To study the corrosion problem of a certain aircraft, and to formulate structure corrosion repairing and anti-corrosion measures. Methods The corrosion reasons and the defects of the structure protection system were ob-tained after statistical analysis of aircraft corrosion classification and combing of the existing aircraft protection system. On the basis of aircraft serving area environment measurement, the aircraft ground parking environmental spectrum and the lo-cal environmental spectrum were developed. The design improvement measures for the structure protection system were taken, and the improvement effect of the design was verified by the accelerated corrosion test. Results Compared to the o-riginal state before improvement of the structure design, the calendar life of the anti-corrosion improvement structure was extend by 1. 6 to 5 times. Conclusion The aircraft was easy to subject to a variety of types of corrosion problems under the weak protection system. Good effect could only be achieved through systematic treatment of the problems in aircraft struc-ture corrosion.%目的:针对某型飞机的腐蚀问题开展研究,制定结构腐蚀修理和防腐改进措施。方法对外场飞机的腐蚀情况进行统计归类,对现有飞机防护体系进行梳理,分析结构腐蚀原因和防护体系的不足。在对飞机服役地区环境进行实测的基础上,编制飞机地面停放环境谱和飞机结构局部环境谱。研究制定结构防护体系设计改进措施,并通过加速腐蚀试验验证设计改进效果。结果与结构设计改进前的原始状态相比,防腐改进后的结构日历寿命提高1.6~5倍。结论飞机防护体系薄弱的情况下容易引发多种类型的腐蚀问题;系统地对飞机结构腐蚀问题进行治理,才能取得令人满意的效果。

  9. Effects of vocationally oriented medical rehabilitation for aircraft maintenance personnel--a preliminary study of long-term effects with 5-year follow-up.

    Science.gov (United States)

    Holopainen, Kaj; Nevala, Nina; Kuronen, Pentti; Arokoski, Jari P A

    2004-12-01

    Changes in the physical capacity, musculoskeletal symptoms, and perceived work ability of Finnish Air Force maintenance personnel were studied after vocationally oriented medical rehabilitation (VOMR). Twenty persons with chronic musculoskeletal symptoms in their back or neck took part in VOMR courses. The measurements were carried out at the beginning of the rehabilitation course and after two follow-up periods (0.5 and 5 years). The subjects worked most of the time in a bent position and often with their backs twisted and their arms above their shoulders. The severity of low-back pain and the number of days of sick leave decreased significantly (p < 0.05-0.01) during the 5-years follow-up. Also the exercise breaks at work increased (p < 0.01). After half a year of medical rehabilitation the measured range of the cervical spine and the dynamic and endurance strength of the upper and lower extremities was greater (p < 0.05-0.001) than at the beginning of the rehabilitation. There were no statistically significant differences in the use of physical therapy, experienced work strain, physical exercise or maximal oxygen consumption during the follow-up. This is a preliminary follow-up study lasting 5 years showed some significant changes in physical capacity, musculoskeletal symptoms and work ability. However, controlled studies are needed to evaluate these preliminary findings of this kind of rehabilitation model.

  10. Improvement of availability of PWR nuclear plants through the reduction of the time required for refueling/maintenance outages

    Energy Technology Data Exchange (ETDEWEB)

    Mayers, J.B.; Soth, L.G.

    1978-04-01

    The objective of the project, conducted by Commonwealth Research Corporation and Westinghouse Electric Corporation, is to identify improvements in procedures and equipment which will reduce the time required for refueling/maintenance outages at PWR nuclear power plants. The outage of Commonwealth Edison Zion Station Unit 1 in March through May of 1976 was evaluated to identify those items which caused delays and those work activities that offer the potential for significant improvements that could reduce the overall duration of the outage and achieve an improvement in the plant's availability for power production. Modifications in procedures have been developed and were evaluated during one or more outages in 1977. Conceptual designs have been developed for equipment modifications to the refueling system that could reduce the time required for the refueling portion of the outage. The purpose of the interim report is to describe those conceptual designs and to assess their impact upon future outages. Recommendations are included for the implementation of these equipment improvements in a continuation of this program as a demonstration of plant availability benefits that can be realized in PWR nuclear plants already in operation or under construction.

  11. Low-dosage epoetin in maintenance haemodialysis: costs and quality-of-life improvement.

    Science.gov (United States)

    Harris, D C

    1994-01-01

    Decisions about epoetin (recombinant human erythropoetin) dosage and target haematocrit in dialysis patients have been determined largely by the high acquisition cost of epoetin, but are made with incomplete knowledge about which target haematocrit gives the optimum clinical benefit. Haematopoietic response to epoetin may be determined by pharmacodynamic factors such as rate and frequency of administration, as well as by individual patient characteristics such as ethnicity. Resistance to epoetin may be due to iron or vitamin deficiency, natural or exogenous inhibitors of erythropoiesis and bone marrow fibrosis. The high acquisition cost of epoetin must be considered along with a number of other factors that can influence the true cost of epoetin treatment. Hidden costs of epoetin treatment include administration costs, changes in other treatments, extra laboratory tests and adverse events. Administration costs and extra laboratory surveillance add little to overall cost. Depletion of iron stores, hypertension, increased blood coagulability and reduced dialyser efficiency resulting from epoetin treatment may all add a small additional component to the true cost. Severe complications with significant cost implications are rare. Amongst the various components of true cost, only the acquisition cost can definitely be reduced by low dosage treatment. Balanced against the true and potential costs of epoetin are a number of benefits which can result in potential savings. The need for blood transfusion is all but abolished, avoiding the cost of transfusion and its complications. Sensitisation against histocompatibility antigens is reduced by avoiding transfusion, and so the waiting time for cadaveric transplantation may be reduced. Rates of hospitalisation for all causes, especially those associated with anaemia, may be reduced by epoetin treatment. By improving well-being, epoetin may allow patients to be transferred to minimal-care units or home where dialysis can be

  12. IMPROVING AIRCRAFT PARTS DUE TO USING NANO-COMPOSITE AND MICRO-COMPOSITE MATERIAL

    Directory of Open Access Journals (Sweden)

    Hassany Merhdad Boer

    2017-01-01

    Full Text Available In this paper it is investigated how to make composite carbon nanofiber/ epoxy resin and carbon micro-fiber / epoxy resin. Also, these materials' features are compared and it is shown how effective and benefitial are the received products containing carbon nano- and micro-fibers.In this study, epoxy composites were prepared in order to improve their mechanical and electrical properties. Ergo, carbon nanofibers and carbon microfibers were used as fillers. On the one hand, purchased microfibers were incorporatedinto the epoxy resin to produce epoxy/carbon microfiber composites via mechanical mixing at 1800 rpm in different concentrations (0.0125, 0.0225, 0.05, and 0.1.On the other hand, carbon nanofibers were prepared via electrospining method at room temperature, then epoxy/carbon nanofiber nanocomposites were prepared at mixing temperature of 60 °C at 1200 rpm at different concentrations (0.0125, 0.05, and 0.1.Morphology of samples was investigated via Field Emission Scanning Electron Microscopy (FESEM. Mechanical properties of samples were investigated via tensile and bending tests. Tensile test results revealed that incorporation of 0.0125 wt% carbon naofibers increased the epoxy resins modulus about 200%. Bending strength of sample containing 0.1wt% carbon microfibers had the most increment (from 20 to 100 MPa.

  13. Improving Effectiveness Of E-Learning In Maintenance Using Interactive-3D

    Directory of Open Access Journals (Sweden)

    Nikhil Lobo

    2009-09-01

    Full Text Available In aerospace and defense, training is being carried out on the web by viewing PowerPoint presentations, manuals and videos that are limited in their ability to convey information to the technician. Interactive training in the form of 3D is a more cost effective approach compared to creation of physical simulations and mockups. This paper demonstrates how training using interactive 3D simulations in e-learning achieves a reduction in the time spent in training and improves the efficiency of a trainee performing the installation or removal..Keywords: Interactive 3D, E-Learning, Training, Simulation

  14. Maintenance and improvement of interobserver reliability of osteopathic palpatory tests over a 4-month period.

    Science.gov (United States)

    Degenhardt, Brian F; Johnson, Jane C; Snider, Karen T; Snider, Eric J

    2010-10-01

    Few studies have shown that diagnostic palpation is reliable. No studies have shown that the reliability of diagnostic palpatory skills can be maintained and improved over time. To investigate whether the reliability of selected palpatory tests used to identify lumbar somatic dysfunction was maintained during a 4-month period as part of a clinical observational study. Participants with low back pain and participants without low back pain, recruited from a rural Midwestern community, were examined during 6 separate sessions over a 4-month period. During each data collection session, two blinded examiners, who had previously completed comprehensive consensus training, evaluated the lumbar region with four tests: static segmental positional asymmetry of the transverse processes in the horizontal plane, tissue texture abnormalities, resistance to anterior springing on the spinous processes, and tenderness induced by pressure on the spinous processes. Detailed protocols for each test were defined during a previous comprehensive consensus training period and were not revised during the current study. To verify that established interobserver reliability was maintained throughout the clinical study, quality control sampling was performed on all data. When findings were inconsistent between the two examiners, focused consensus training was performed as a means of recalibration to understand why assessments were inconsistent. Interobserver reliability for determining the presence or absence of somatic dysfunction was assessed using kappa coefficients. The study enrolled 64 participants, and 14 to 33 participants were examined per session. All four tests had acceptable interobserver reliability by the final data collection session. The test for static segmental positional asymmetry of the transverse processes in the horizontal plane had moderate to substantial reliability in all 6 sessions. The test for tissue texture abnormalities had moderate reliability in 5 of the 6

  15. Community pharmacy automatic refill program improves adherence to maintenance therapy and reduces wasted medication.

    Science.gov (United States)

    Matlin, Olga S; Kymes, Steven M; Averbukh, Alice; Choudhry, Niteesh K; Brennan, Troyen A; Bunton, Andred; Ducharme, Timothy A; Simmons, Peter D; Shrank, William H

    2015-11-01

    Automatic prescription refill programs are a popular means of improving medication adherence. A concern is the potential for prescription drug wastage and unnecessary healthcare spending. We evaluated the impact of an automatic refill program on patterns of medication use. Retrospective propensity score matched cohort study with multivariable generalized linear modeling. The setting of the study was a pharmacy benefit manager administering benefits for patients of retail pharmacies. Participants included patients on medication for chronic conditions; those receiving a 30-day supply (n = 153,964) and a 90-day supply (n = 100,394) were analyzed separately. The intervention was the automatic prescription refill program. Measures included medication possession ratio (MPR) and average days excess at the time of refill. The results are reported across 11 therapeutic classes. Overall, patients receiving 30-day supplies of medication in the automatic refill program had an MPR that was 3 points higher than those not in the refill program; among those receiving 90-day fills and in the refill program, the MPR was 1.4 points higher (P < .001 for both 30- and 90-day fills). The MPR was higher for members in the refill program across all therapeutic classes. Limiting our analysis to members receiving more than 365 days of medication, we found that patients who received 30-day fills and enrolled in the automatic refill program had 2.5 fewer days' oversupply than those in the control group, whereas automatic refill patients receiving 90-day supplies had 2.18 fewer days' oversupply than the controls (P < .001 for both 30- and 90-day fills). For this pharmacy provider, automatic refill programs result in improved adherence without adding to medication oversupply.

  16. 14 CFR 125.245 - Organization required to perform maintenance, preventive maintenance, and alteration.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Organization required to perform maintenance, preventive maintenance, and alteration. 125.245 Section 125.245 Aeronautics and Space FEDERAL... GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Maintenance § 125.245 Organization required to perform...

  17. 14 CFR 91.1433 - CAMP: Maintenance and preventive maintenance training program.

    Science.gov (United States)

    2010-01-01

    ... maintenance training program. Each program manager who maintains program aircraft under a CAMP or a person... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false CAMP: Maintenance and preventive maintenance training program. 91.1433 Section 91.1433 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION...

  18. Turbine maintenance and modernization

    Energy Technology Data Exchange (ETDEWEB)

    Unga, E. [Teollisuuden Voima Oy, Olkiluoto (Finland)

    1998-12-31

    The disturbance-free operation of the turbine plant plays an important role in reaching good production results. In the turbine maintenance of the Olkiluoto nuclear power plant the lifetime and efficiency of turbine components and the lifetime costs are taken into account in determining the turbine maintenance and modernization/improvement program. The turbine maintenance program and improvement/modernization measures taken in the plant units are described in this presentation. (orig.)

  19. Effectiveness of Cognitive-Behavioral Group Therapy on Improving Quality of Life in Opiate Addicts under Methadone Maintenance Treatment

    Directory of Open Access Journals (Sweden)

    Fereshteh Momeni

    2013-04-01

    Full Text Available Objective: This study was aimed to assess the effectiveness of cognitive- behavioral group therapy on improvement of quality of life in opiate patients under methadone maintenance treatment. Method: This was a semi experimental study using control group also pre-test, post-test and follow-up. Thirty six patients on MMT were selected between the entire opiate addicts referred to Iranian national center for addiction studies within judgmental sampling and were randomly assigned into experimental and control groups. They were all administered the WHOQOL-BREF. In experimental group, cognitive behavior group therapy was performed in 8 sessions and the control group was registered in the waiting list for the CBGT. Findings: Data analysis revealed that the mean WHOQOL-BREF score in the experimental group had significant higher increase when compared with that of the control group. But it wasn’t significant in follow up. Conclusion: Results demonstrated the effectiveness of cognitive–behavior group therapy On improvement of quality of life of opiate addicts on MMT in short term but didn’t seem to be effective in long term.

  20. 14 CFR 91.327 - Aircraft having a special airworthiness certificate in the light-sport category: Operating...

    Science.gov (United States)

    2010-01-01

    ... certificated repairman with a light-sport aircraft maintenance rating, an appropriately rated mechanic, or an... (light-sport aircraft) with a maintenance rating, an appropriately rated mechanic, or an appropriately... certificated repairman with a light-sport aircraft maintenance rating, an appropriately rated mechanic, or...

  1. A method for accounting for maintenance costs in flux balance analysis improves the prediction of plant cell metabolic phenotypes under stress conditions.

    Science.gov (United States)

    Cheung, C Y Maurice; Williams, Thomas C R; Poolman, Mark G; Fell, David A; Ratcliffe, R George; Sweetlove, Lee J

    2013-09-01

    Flux balance models of metabolism generally utilize synthesis of biomass as the main determinant of intracellular fluxes. However, the biomass constraint alone is not sufficient to predict realistic fluxes in central heterotrophic metabolism of plant cells because of the major demand on the energy budget due to transport costs and cell maintenance. This major limitation can be addressed by incorporating transport steps into the metabolic model and by implementing a procedure that uses Pareto optimality analysis to explore the trade-off between ATP and NADPH production for maintenance. This leads to a method for predicting cell maintenance costs on the basis of the measured flux ratio between the oxidative steps of the oxidative pentose phosphate pathway and glycolysis. We show that accounting for transport and maintenance costs substantially improves the accuracy of fluxes predicted from a flux balance model of heterotrophic Arabidopsis cells in culture, irrespective of the objective function used in the analysis. Moreover, when the new method was applied to cells under control, elevated temperature and hyper-osmotic conditions, only elevated temperature led to a substantial increase in cell maintenance costs. It is concluded that the hyper-osmotic conditions tested did not impose a metabolic stress, in as much as the metabolic network is not forced to devote more resources to cell maintenance.

  2. The American Board of Radiology Perspective on Maintenance of Certification: Part IV: Practice quality improvement in radiologic physics.

    Science.gov (United States)

    Frey, G Donald; Ibbott, Geoffrey S; Morin, Richard L; Paliwal, Bhudatt R; Thomas, Stephen R; Bosma, Jennifer

    2007-11-01

    Recent initiatives of the American Board of Medical Specialties (ABMS) in the area of maintenance of certification (MOC) have been reflective of the response of the medical community to address public concerns regarding quality of care, medical error reduction, and patient safety. In March 2000, the 24 member boards of the ABMS representing all medical subspecialties in the USA agreed to initiate specialty-specific maintenance of certification (MOC) programs. The American Board of Radiology (ABR) MOC program for diagnostic radiology, radiation oncology, and radiologic physics has been developed, approved by the ABMS, and initiated with full implementation for all three disciplines beginning in 2007. The overriding objective of MOC is to improve the quality of health care through diplomate-initiated learning and quality improvement. The four component parts to the MOC process are: Part I: Professional standing, Part II: Evidence of life long learning and periodic self-assessment, Part III: Cognitive expertise, and Part IV: Evaluation of performance in practice (with the latter being the focus of this paper). The key components of Part IV require a physicist-based response to demonstrate commitment to practice quality improvement (PQI) and progress in continuing individual competence in practice. Diplomates of radiologic physics must select a project to be completed over the ten-year cycle that potentially can improve the quality of the diplomate's individual or systems practice and enhance the quality of care. Five categories have been created from which an individual radiologic physics diplomate can select one required PQI project: (1) Safety for patients, employees, and the public, (2) accuracy of analyses and calculations, (3) report turnaround time and communication issues, (4) practice guidelines and technical standards, and (5) surveys (including peer review of self-assessment reports). Each diplomate may select a project appropriate for an individual

  3. Aircraft Carriers

    DEFF Research Database (Denmark)

    Nødskov, Kim; Kværnø, Ole

    There are many indications that China is actively researching the design of an aircraft carrier. It is unknown whether China will initiate the actual acquisition of a carrier, but the indications that are available of their research into aircraft carriers and carrier-capable aircraft, as well...... as their purchases of aircraft carrier systems, makes it more than likely that the country is preparing such an acquisition. China has territorial disputes in the South China Sea over the Spratly Islands and is also worried about the security of its sea lines of communications, by which China transports the majority...... of its foreign trade, as well as its oil imports, upon which the country is totally dependent. China therefore has good reasons for acquiring an aircraft carrier to enable it to protect its national interests. An aircraft carrier would also be a prominent symbol of China’s future status as a great power...

  4. 14 CFR 135.419 - Approved aircraft inspection program.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Approved aircraft inspection program. 135.419 Section 135.419 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Maintenance, Preventive Maintenance, and Alterations § 135.419 Approved aircraft inspection program....

  5. Network maintenance

    CERN Multimedia

    GS Department

    2009-01-01

    A site-wide network maintenance operation has been scheduled for Saturday 28 February. Most of the network devices of the general purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites throughout the day. This upgrade will not affect the Computer Centre itself, Building 613, the Technical Network and the LHC experiments, dedicated networks at the pits. For further details of this intervention, please contact Netops by phone 74927 or e-mail mailto:Netops@cern.ch. IT/CS Group

  6. Network maintenance

    CERN Multimedia

    IT Department

    2009-01-01

    A site wide network maintenance has been scheduled for Saturday 28 February. Most of the network devices of the General Purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites along this day. This upgrade will not affect: the Computer centre itself, building 613, the Technical Network and the LHC experiments dedicated networks at the pits. Should you need more details on this intervention, please contact Netops by phone 74927 or email mailto:Netops@cern.ch. IT/CS Group

  7. The Comparison of Effectiveness of Cognitive-Behavioral Group Therapy Based on Coping Skills and Methadone Maintenance Treatment in Improvement of Emotional Regulation Strategies and Relapse Prevention

    Directory of Open Access Journals (Sweden)

    Tahereh Ghorbany

    2011-05-01

    Full Text Available Purpose: This study compared the effectiveness of group cognitive-behavioral therapy based on coping skills (CBT and methadone maintenance therapy (MMT in improvement of emotional regulation strategies and prevention of relapse. Method: The method of the present study was semi-experimental research design (pre-test-post-test with witness group. For sampling 45 substance abuse people who had referred to addiction treatment centers were selected and assigned to three groups of cognitive behavior therapy, methadone maintenance treatment and witness group randomly. The participants in all three groups completed the emotional intelligence questionnaire before and after the intervention. Data were analyzed by covariance method. Results: The results showed that cognitive-behavior therapy in comparison to methadone maintenance therapy and witness group led to significant improvement of emotional regulation in substance abusers, but there was no significant difference between the methadone maintenance treatment group and control group. Also, the rate of relapse in individuals who assigned to cognitive-behavior therapy group in comparison to methadone maintenance therapy and the witness group was significantly lower, but there was no significant difference between methadone therapy and witness. Conclusion: Cognitive-behavior therapy was an effective treatment that can change the cognitive and behavioral variables related to substance abuse, such as emotional regulation strategies. Thus, results suggested that drug abuse treatment programs must target these mediator variables.

  8. Using visual cues of contact to improve interactive manipulation of virtual objects in industrial assembly/maintenance simulations.

    Science.gov (United States)

    Sreng, Jean; Lécuyer, Anatole; Mégard, Christine; Andriot, Claude

    2006-01-01

    This paper describes a set of visual cues of contact designed to improve the interactive manipulation of virtual objects in industrial assembly/maintenance simulations. These visual cues display information of proximity, contact and effort between virtual objects when the user manipulates a part inside a digital mock-up. The set of visual cues encloses the apparition of glyphs (arrow, disk, or sphere) when the manipulated object is close or in contact with another part of the virtual environment. Light sources can also be added at the level of contact points. A filtering technique is proposed to decrease the number of glyphs displayed at the same time. Various effects--such as change in color, change in size, and deformation of shape- can be applied to the glyphs as a function of proximity with other objects or amplitude of the contact forces. A preliminary evaluation was conducted to gather the subjective preference of a group of participants during the simulation of an automotive assembly operation. The collected questionnaires showed that participants globally appreciated our visual cues of contact. The changes in color appeared to be preferred concerning the display of distances and proximity information. Size changes and deformation effects appeared to be preferred in terms of perception of contact forces between the parts. Last, light sources were selected to focus the attention of the user on the contact areas.

  9. [Acupuncture therapy for the improvement of sleep quality of outpatients receiving methadone maintenance treatment: a randomized controlled trial].

    Science.gov (United States)

    Li, Yi; Liu, Xue-bing; Zhang, Yao

    2012-08-01

    To study the efficacy and safety of acupuncture therapy for the improvement of sleep quality of outpatients receiving methadone maintenance treatment (MMT). Using randomized double-blinded controlled design, seventy-five MMT outpatients with low sleep quality [score of Pittsburgh sleep quality index (PSQI) > or = 8], were randomly assigned to the acupuncture group (38 cases) and the sham-acupuncture group (37 cases). All patients maintained previous MMT. Acupuncture was applied to Baihui (GV20), Shenmen (bilateral, TF4), Shenting (GV24), Sanyinjiao (bilateral, SP6), and Sishencong (EX-HN1) in the acupuncture group. The same procedures were performed in the sham-acupuncture group, but not to the acupoints (5 mm lateral to the acupoints selected in the acupuncture group) with shallow needling technique. The treatment was performed 5 times each week for 8 successive weeks. The PSQI was assessed before treatment, at the end of the 2nd, 4th, 6th, and 8th week of the treatment. The detection ratio of low sleep quality and the incidence of adverse acupuncture reactions were compared between the two groups at the end of the 8th week. The overall PSQI score was obviously higher in the acupuncture group than in the sham-acupuncture group with statistical difference (P acupuncture group (60.53%, 23/38 cases) than in the sham-acupuncture group (83.78%, 31/37 cases) with statistical difference (P acupuncture reaction was 5.26% (2/38 cases) in the acupuncture group and 2.70% (1/37 cases) in the sham-acupuncture group respectively, showing no statistical difference (P > 0.05). Acupuncture therapy could effectively and safely improve the sleep quality of outpatients receiving MMT.

  10. Aircraft Design

    Science.gov (United States)

    Bowers, Albion H. (Inventor); Uden, Edward (Inventor)

    2016-01-01

    The present invention is an aircraft wing design that creates a bell shaped span load, which results in a negative induced drag (induced thrust) on the outer portion of the wing; such a design obviates the need for rudder control of an aircraft.

  11. DoD Needs to Improve Vocational Training Efforts to Develop the Afghan National Security Forces Infrastructure Maintenance Capabilities

    Science.gov (United States)

    2012-06-18

    level (apprentice, journeyman, or craftsman ) in each facility maintenance trade and stated that training will continue until the students demonstrate...11A performance standard for a vocational skill level could be an apprentice, journeyman, or craftsman . A vocation type for

  12. Technical Documentation Challenges in Aviation Maintenance: A Proceedings Report

    Science.gov (United States)

    2012-11-01

    Repair, and Overhaul organizations ( MROs ) where each aircraft must be maintained by maintenance documentation specific to the aircraft owner and...registry number. This means that an MRO is likely to have different work instructions for each aircraft in the shop, even though they are the same...documentation for aviation maintenance. All 28 attendees possessed considerable expertise from either operations or science, including MROs , Original

  13. Practical research in maintenance optimization and improvement of medium speed mill ZGM123%ZGM123中速磨煤机检修优化与改造

    Institute of Scientific and Technical Information of China (English)

    刘海龙; 金日锋; 王勇

    2012-01-01

    This paper introduced the practical research on maintenance optimization of the mill in Tianjin Datang International Panshan Power Generation Limited Company. Firstly, the maintenance optimization of mill is based on spot inspection and reg ular repair, by which the reasonable and economical maintenance cycle is determined. Secondly, throgh improving the equip ment by the advanced process technology, the workload and the consumption of spare parts in heavy maintenance are decreased, and the maintenance optimization is achieved.%介绍了天津大唐国际盘山发电有限责任公司磨煤机的检修优化的实践和研究,磨煤机的检修优化首先是要基于点检定修的深入开展,通过点检定修确定合理、经济的检修周期;其次是通过采用先进的工艺技术对设备进行改造,从而减少磨煤机大修时的检修工作量和备件消耗,达到检修优化.

  14. An Intelligent Fleet Condition-Based Maintenance Decision Making Method Based on Multi-Agent

    Directory of Open Access Journals (Sweden)

    Bo Sun

    2012-01-01

    Full Text Available According to the demand for condition-based maintenance online decision making among a mission oriented fleet, an intelligent maintenance decision making method based on Multi-agent and heuristic rules is proposed. The process of condition-based maintenance within an aircraft fleet (each containing one or more Line Replaceable Modules based on multiple maintenance thresholds is analyzed. Then the process is abstracted into a Multi-Agent Model, a 2-layer model structure containing host negotiation and independent negotiation is established, and the heuristic rules applied to global and local maintenance decision making is proposed. Based on Contract Net Protocol and the heuristic rules, the maintenance decision making algorithm is put forward. Finally, a fleet consisting of 10 aircrafts on a 3-wave continuous mission is illustrated to verify this method. Simulation results indicate that this method can improve the availability of the fleet, meet mission demands, rationalize the utilization of support resources and provide support for online maintenance decision making among a mission oriented fleet.

  15. PLANNING OF TRAINING AIRCRAFT FLIGHT HOURS

    Directory of Open Access Journals (Sweden)

    Visnja Vojvodić Rosenzweig

    2010-12-01

    Full Text Available Maintenance of the training aircraft causes downtime of operations and thereby reduces the operational availability, which is crucial for flight planning in a training organisation. Manual daily planning within the fleet delivers suboptimal results and often causes discontinued flight of several aircraft that have to be maintained at the same time. Optimal maintenance schedule of training aircraft can be obtained by a sliding scale method. This paper presents a mathematical model of the sliding scale formulated by a mixed integer linear problem. Allocation of flight hours is optimised by using AMPL programming language, assuring that a sufficient number of aircraft are always available for training. The model can be used by a flight dispatch department in a training organisation as a basis for optimised planning and reduction of maintenance downtime.

  16. Examining maintenance responsibilities.

    Science.gov (United States)

    Lam, K C

    2001-06-01

    This paper has examined the important responsibilities of the two organisations involved in the provision of maintenance service for the vital building services in many of our highly serviced buildings. The issues raised could be put to beneficial use in both clients and maintenance providers. All in all, the clients should work closely with their maintenance providers. Engineering services in buildings will not perform satisfactorily and efficiently if both parties do not work together and understand the maintenance tasks based on a business partnering mode. Put forward is the view that the management of the activities involved in the operation and maintenance process is a "shared commitment/involvement" between the client and the maintenance provider. It is obvious that many factors can influence the continued effectiveness of a quality maintenance scheme set up by client and provider. Some of these factors are: Change in key personnel Updates in technology Amendments to engineering practice Implementation of legislative requirements Changes in operation by client or provider Change of use of building Passage of time These factors must be fully reviewed by both parties from time to time, and necessary actions taken. A cooperative team working relationship and improved communication should be fostered by the client and his provider for the best management of services maintenance. This arrangement will contribute to better building services systems with continuous improvement; improved value for clients and higher return for the maintenance provider.

  17. Productivity Measurement in Aircraft Maintenance Organizations

    Science.gov (United States)

    1990-09-01

    1.9824 0.1616 10 " ORIN 8 0.0130 0.2568 3.4461 0.6776 0.415V 11 34 7 0.0275 0.2292 2.6853 1.4450 0.2366 12 37 6 0.0378 0.1114 2.3864 1.6618 0.1690 13...Huse, Edgar F. Management. (Second Editon). St. Paul MN: West Publishing Co. 1982. 21. Daft, Richard L. and Richard M. Steers. Organizations. A Micro

  18. Job Attitudes of USAF Aircraft Maintenance Personnel.

    Science.gov (United States)

    1986-04-01

    8217" . * " ."".." " " - %’p *. faction and productivity in the workplace (Steers, 1981). Frederick Herzberg , in his Two-Factor Theory, thought V. of job satisfaction...are responsibility, recogni- tion, the work itself and achievement (Williams, 1978). Herzberg felt that the lack of motivation factors would not...job satisfaction has only scratched the surface. Certain motivation theories, such as ’aslow and Herzberg are general and their abilities to be

  19. Evaluation of Tactile Situation Awareness System as an Aid for Improving Aircraft Control During Periods of Impaired Vision

    Science.gov (United States)

    2009-06-01

    chokepoint limiting command and control of the aircraft. Fortunately, vision can be augmented with an available technology called “ haptics ” during...application of haptics or tactile devices for flight purposes began in the mid- 1990s with proof of concept performed in 1995 in a Cessna 172 (Rupert, 1997...According to Rupert, he designed the haptic piloting device and named it the Tactile Situational Awareness System (TSAS). Naval Air Base

  20. Low-mutation-rate, reduced-genome Escherichia coli: an improved host for faithful maintenance of engineered genetic constructs

    Directory of Open Access Journals (Sweden)

    Csörgő Bálint

    2012-01-01

    Full Text Available Abstract Background Molecular mechanisms generating genetic variation provide the basis for evolution and long-term survival of a population in a changing environment. In stable, laboratory conditions, the variation-generating mechanisms are dispensable, as there is limited need for the cell to adapt to adverse conditions. In fact, newly emerging, evolved features might be undesirable when working on highly refined, precise molecular and synthetic biological tasks. Results By constructing low-mutation-rate variants, we reduced the evolutionary capacity of MDS42, a reduced-genome E. coli strain engineered to lack most genes irrelevant for laboratory/industrial applications. Elimination of diversity-generating, error-prone DNA polymerase enzymes involved in induced mutagenesis achieved a significant stabilization of the genome. The resulting strain, while retaining normal growth, showed a significant decrease in overall mutation rates, most notably under various stress conditions. Moreover, the error-prone polymerase-free host allowed relatively stable maintenance of a toxic methyltransferase-expressing clone. In contrast, the parental strain produced mutant clones, unable to produce functional methyltransferase, which quickly overgrew the culture to a high ratio (50% of clones in a 24-h induction period lacked functional methyltransferase activity. The surprisingly large stability-difference observed between the strains was due to the combined effects of high stress-induced mutagenesis in the parental strain, growth inhibition by expression of the toxic protein, and selection/outgrowth of mutants no longer producing an active, toxic enzyme. Conclusions By eliminating stress-inducible error-prone DNA-polymerases, the genome of the mobile genetic element-free E. coli strain MDS42 was further stabilized. The resulting strain represents an improved host in various synthetic and molecular biological applications, allowing more stable production of

  1. Maintenance of improved lipid levels following attendance at a cardiovascular risk reduction clinic: a 10-year experience

    Directory of Open Access Journals (Sweden)

    Glen J Pearson

    2008-10-01

    Full Text Available Glen J Pearson1,5, Kari L Olson6, Nicole E Panich1, Sumit R Majumdar2,5, Ross T Tsuyuki1,4, Dawna M Gilchrist2,5, Ali Damani4, Gordon A Francis3,5The MILLARR Study (Maintenance of Improved Lipid Levels Following Attendance at a Cardiovascular Risk Reduction Clinic 1Department of Medicine, Divisions of Cardiology; 2General Internal Medicine; 3Endocrinology and Metabolism; Faculty of Pharmacy and Pharmaceutical Sciences; 4University of Alberta, Edmonton, Alberta, Canada; 5Cardiovascular Risk Reduction Clinic (CRRC, University of Alberta Hospital, Edmonton, Alberta, Canada; 6University of Colorado Health Sciences Center, Denver, Colorado, USA; 7Family Medicine (Private Practice, Calgary, Alberta, CanadaBackground: Specialty cardiovascular risk reduction clinics (CRRC increase the proportion of patients attaining recommended lipid targets; however, it is not known if the benefits are sustained after discharge. We evaluated the impact of a CRRC on lipid levels and assessed the long-term effect of a CRRC in maintaining improved lipid levels following discharge.Methods: The medical records of consecutive dyslipidemic patients discharged >6 months from a tertiary hospital CRRC from January 1991 to January 2001 were retrospectively reviewed. The primary outcome was the change in patients’ lipid levels between the final CRRC visit and the most recent primary care follow-up. A worst-case analysis was conducted to evaluate the potential impact of the patients in whom the follow-up lipid profiles post-discharge from the CRRC were not obtained.Results: Within the CRRC (median follow-up = 1.28 years in 1064 patients, we observed statistically significant improvements in all lipid parameters. In the 411 patients for whom post-discharge lipid profiles were available (median follow-up = 2.41 years, there were no significant differences observed in low-density lipoprotein-cholesterol, total cholesterol (TC, or triglycerides since CRRC discharge; however, there

  2. 14 CFR 121.709 - Airworthiness release or aircraft log entry.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airworthiness release or aircraft log entry... Airworthiness release or aircraft log entry. (a) No certificate holder may operate an aircraft after maintenance... appropriate entry in the aircraft log. (b) The airworthiness release or log entry required by paragraph (a)...

  3. Application of reliability-centered maintenance for productivity improvement of open pit mining equipment:Case study of Sungun Copper Mine

    Institute of Scientific and Technical Information of China (English)

    Amin Moniri Morad; Mohammad Pourgol-Mohammad; Javad Sattarvand

    2014-01-01

    Equipment plays an important role in open pit mining industry and its cost competence at efficient operation and maintenance techniques centered on reliability can lead to significant cost reduction. The application of optimal maintenance process was investigated for minimizing the equipment breakdowns and downtimes in Sungun Copper Mine. It results in the improved efficiency and productivity of the equipment and lowered expenses as well as the increased profit margin. The field operating data of 10 trucks are used to estimate the failure and maintenance profile for each component, and modeling and simulation are accomplished by using reliability block diagram method. Trend analysis was then conducted to select proper probabilistic model for maintenance profile. Then reliability of the system was evaluated and importance of each component was computed by weighted importance measure method. This analysis led to identify the items with critical impact on availability of overall equipment in order to prioritize improvement decisions. Later, the availability of trucks was evaluated using Monte Carlo simulation and it is revealed that the uptime of the trucks is around 11000 h at 12000 operation hours. Finally, uncertainty analysis was performed to account for the uncertainty sources in data and models.

  4. Amphibious Aircraft

    Data.gov (United States)

    National Aeronautics and Space Administration — A brief self composed research article on Amphibious Aircrafts discussing their use, origin and modern day applications along with their advantages and disadvantages...

  5. Aircraft Disinsection

    Science.gov (United States)

    Some countries may require aircraft coming from countries where certain insects or insect-borne diseases are present, such as malaria and Zika virus, to be treated with insecticide. Find out about regulation of pesticides for this treatment.

  6. Optimised Cockpit Heat Load Analysis using Skin Temperature Predicted by CFD and Validation by Thermal Mapping to Improve the Performance of Fighter Aircraft

    Directory of Open Access Journals (Sweden)

    Paresh Gupta

    2015-03-01

    Full Text Available Designing of optimum environmental control system (ECS plays a major role for increasing performance of fighter aircraft depending upon requirement of engine bleed air for running of ECS. Accurate estimation of cockpit skin temperature for obtaining optimised cockpit heat load helps in estimation of engine bleed air for ECS. Present research evolved a methodology for comparing the theoretically calculated skin temperature with computational fluid dynamics (CFD analysis to obtain optimum skin temperature. Results are validated by flight tests under critical flight conditions using thermal crayons. Based on which the optimized heat load and bleed air requirements has been computed. Uncertainty analysis of skin temperature measurement for thermal crayons have been undertaken. The results indicate that the theoretical skin temperature is -26.70 per cent as that of CFD estimated skin temperature. Optimized average cockpit heat load at critical flight profiles is 0.74 times the theoretical cockpit heat load, leading to reduction of bleed air requirement by 26 per cent as compared to theoretical. Due to this literature survey has pridicted the increase in performance parameters like increase in bleed air pressure by 78 per cent, increase in thrust by 60 per cent, and decrease in specific fuel consumption (SFC by 40 per cent to improve the endurance of aircraft. The research has generated governing equations for variation of cockpit heat loads w.r.t aircraft skin temperatures.Defence Science Journal, Vol. 65, No. 1, January 2015, pp.12-24, DOI:http://dx.doi.org/10.14429/dsj.65.7200

  7. 14 CFR 43.5 - Approval for return to service after maintenance, preventive maintenance, rebuilding, or alteration.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Approval for return to service after maintenance, preventive maintenance, rebuilding, or alteration. 43.5 Section 43.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE...

  8. Advanced Aircraft Material

    Directory of Open Access Journals (Sweden)

    Vivek Kumar Prince

    2013-06-01

    Full Text Available There has been long debate on “advanced aircraft material” from past decades & researchers too came out with lots of new advanced material like composites and different aluminum alloys. Now days a new advancement that is in great talk is third generation Aluminum-lithium alloy. Newest Aluminum-lithium alloys are found out to have low density, higher elastic modulus, greater stiffness, greater cryogenic toughness, high resistance to fatigue cracking and improved corrosion resistance properties over the earlier used aircraft material as mentioned in Table 3 [1-5]. Comparison had been made with nowadays used composite material and is found out to be more superior then that

  9. Applying Systems Engineering to Improve the Main Gas Turbine Exhaust System Maintenance Strategy for the CG-47 Ticonderoga Class Cruiser

    Science.gov (United States)

    2015-09-01

    Exhaust Collector Failure Data 2. A Hybrid Approach to Preventative Maintenance Generating a class standard work template (CSWT) that reflects the...new hybrid approach to RCM. The hybrid RCM concept blends an inspection task with a repair task based on historical failure data analysis. The hybrid ...thesis. The analysis recommends a new hybrid approach to RCM. The hybrid RCM concept blends an inspection task with a repair task based on historical

  10. Enhanced slow wave sleep and improved sleep maintenance after gaboxadol administration during seven nights of exposure to a traffic noise model of transient insomnia.

    Science.gov (United States)

    Dijk, D-J; Stanley, N; Lundahl, J; Groeger, J A; Legters, A; Trap Huusom, A K; Deacon, S

    2012-08-01

    Slow wave sleep (SWS) has been reported to correlate with sleep maintenance, but whether pharmacological enhancement of SWS also leads to improved sleep maintenance is not known. Here we evaluate the time-course of the effects of gaboxadol, an extra-synaptic gamma-aminobutyric acid (GABA) agonist, on SWS, sleep maintenance, and other sleep measures in a traffic noise model of transient insomnia. After a placebo run-in, 101 healthy subjects (20-78 y) were randomized to gaboxadol (n = 50; 15 mg in subjects <65 y and 10 mg in subjects ≥65 y) or placebo (n = 51) for 7 nights (N1-N7). The model caused some disruption of sleep initiation and maintenance, with greatest effects on N1. Compared with placebo, gaboxadol increased SWS and slow wave activity throughout N1 to N7 (p < 0.05). Gaboxadol reduced latency to persistent sleep overall (N1-N7) by 4.5 min and on N1 by 11 min (both p < 0.05). Gaboxadol increased total sleep time (TST) overall by 16 min (p < 0.001) and on N1 by 38 min (p < 0.0001). Under gaboxadol, wakefulness after sleep onset was reduced by 11 min overall (p < 0.01) and by 29 min on N1 (p < 0.0001), and poly-somnographic awakenings were reduced on N1 (p < 0.05). Gaboxadol reduced self-reported sleep onset latency overall and on N1 (both p < 0.05) and increased self-reported TST overall (p < 0.05) and on N1 (p < 0.01). Subjective sleep quality improved overall (p < 0.01) and on N1 (p < 0.0001). Increases in SWS correlated with objective and subjective measures of sleep maintenance and subjective sleep quality under placebo and gaboxadol (p < 0.05). Gaboxadol enhanced SWS and reduced the disruptive effects of noise on sleep initiation and maintenance.

  11. The proposal for reliability improvement of emergency diesel engines through the evaluation of the maintenance program and overseas cases for their applications

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, H. J.; Zee, M. H.; Choi, G. H.; Hong, S. R. [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Jeo, G. H. [Korea Maritime Univ., Busan (Korea, Republic of); Ahn, S. K. [Pukyong National Univ., Busan (Korea, Republic of)

    2003-10-01

    The failure frequency of the Emergency Diesel Generator(EDG) at Nuclear Power Plants(NPPs) is not so much lower than that of the Marine engines, whereas the running hours of the diesel engine at NPPs is much less than those of the engines for commercial service. The primary factor results from the severe surveillance test requirements such as fast start, large number of starting test, fast load-run, high load running, etc. The other factor comes from the excessive maintenance based on the engine maker's instruction manual that did not incorporate the peculiar characteristics of the diesel engines at NPPs. In this paper, the present preventive maintenance program on the basis of the Pielstick diesel engines was reviewed for the purpose of securing the reliability of the emergency diesel generator at NPPs and the ways for its improvement were presented by referring to the overseas cases for their applications.

  12. Software Maintenance.

    Science.gov (United States)

    Cannon, Glenn; Jobe, Holly

    Proper cleaning and storage of audiovisual aids is outlined in this brief guide. Materials and equipment needed for first line maintenance are listed, as well as maintenance procedures for records, audio and video tape, film, filmstrips, slides, realia, models, prints, graphics, maps, and overhead transparencies. A 15-item quiz on software…

  13. Aircraft cybernetics

    Science.gov (United States)

    1977-01-01

    The use of computers for aircraft control, flight simulation, and inertial navigation is explored. The man-machine relation problem in aviation is addressed. Simple and self-adapting autopilots are described and the assets and liabilities of digital navigation techniques are assessed.

  14. How to improve vehicle maintenance Total Quality Management%浅析怎样搞好汽车维修全面质量管理

    Institute of Scientific and Technical Information of China (English)

    敖克勇

    2014-01-01

    Total Quality Management is a vehicle maintenance vehicle maintenance is an important part of enterprise management is a key aspect of vehicle maintenance service work. Contemporary Vehicle Quality management is the use of modern scientific tools and methods to ensure and improve the quality of vehicle repair, car repair a comprehensive range of quality management is customer reception, incoming inspection, troubleshooting, parts supply, maintenance operations, intermediate test, test test , the whole process of delivery of the vehicle. Business-related departments to be involved in total quality management, the formation of a comprehensive quality management system, and make it run efficiently, promote enterprise development.%汽车维修全面质量管理是汽车维修企业管理中的重要内容,也是汽车维修服务工作的关键环节。当代汽车维修质量管理就是运用现代科学的手段和方法来保证和提高汽车维修质量,全面汽车维修质量管理的范围是客户接待、进厂检验、故障诊断、配件供应、维修作业、中间检验、检验试车、交车全过程。企业相关部门都要参与全面质量管理,形成全面质量管理体系,并使之有效运行,促进企业发展。

  15. Operation of the aircraft as a discipline of knowledge after 100 years of experience

    Directory of Open Access Journals (Sweden)

    Stanisław Danilecki

    2015-12-01

    Full Text Available The paper presents the course of the most important stages of development of the discipline related to the maintenance of aircrafts, as a synthesis of the 100-year experience. It is presented linking of technical maintenance of the aircraft with other disciplines of knowledge. The scope of technical maintenance was defined. The division and analysis of the methods for the maintenance was made. There were defined and discussed definitions used in the theory of maintenance, in conjunction with the construction of the aircraft and the tasks arising for constructor-manufacturer. MSG subsequent versions of the document constituting the logistical procedures for determining the programmable handling of civil airplanes were discussed.[b]Keywords[/b]: aviation, aircraft, maintenance aircrafts

  16. International Atomic Energy Agency specialists meeting on experience in ageing, maintenance, and modernization of instrumentation and control systems for improving nuclear power plant availability

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    This report presents the proceedings of the Specialist`s Meeting on Experience in Aging, Maintenance and Modernization of Instrumentation and Control Systems for Improving Nuclear Power Plant Availability that was held at the Ramada Inn in Rockville, Maryland on May 5--7, 1993. The Meeting was presented in cooperation with the Electric Power Research Institute, Oak Ridge National Laboratory and the International Atomic Energy Agency. There were approximately 65 participants from 13 countries at the Meeting. Individual reports have been cataloged separately.

  17. Scorpion: Close Air Support (CAS) aircraft

    Science.gov (United States)

    Allen, Chris; Cheng, Rendy; Koehler, Grant; Lyon, Sean; Paguio, Cecilia

    1991-01-01

    The objective is to outline the results of the preliminary design of the Scorpion, a proposed close air support aircraft. The results obtained include complete preliminary analysis of the aircraft in the areas of aerodynamics, structures, avionics and electronics, stability and control, weight and balance, propulsion systems, and costs. A conventional wing, twin jet, twin-tail aircraft was chosen to maximize the desirable characteristics. The Scorpion will feature low speed maneuverability, high survivability, low cost, and low maintenance. The life cycle cost per aircraft will be 17.5 million dollars. The maximum takeoff weight will be 52,760 pounds. Wing loading will be 90 psf. The thrust to weight will be 0.6 lbs/lb. This aircraft meets the specified mission requirements. Some modifications have been suggested to further optimize the design.

  18. Improvement of availability of PWR nuclear plants through the reduction of the time required for refueling/maintenance outages, Phase 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, C.A.

    1978-08-01

    The objective of this project is to identify improvements in procedures and equipment which will reduce the time required for refueling/maintenance outages at PWR nuclear power plants. The outage of Commonwealth Edison Zion Station Unit 1 in March through May of 1976 was evaluated to identify those items which caused delays and those work activities that offer the potential for significant improvements toward reducing its overall duration. Thus, the plant's availability for power production would be increased. Revisions in procedures and some equipment modifications were implemented and evaluated during the Zion Unit 2 refueling/maintenance outage beginning in January 1977. Analysis of the observed data has identified benefits available through improved refueling equipment and also areas where additional new, innovative refueling, or refueling-related equipment should be beneficial. A number of specific design concepts are recommended as a result of Phase 1. In addition, a new master planning mechanism is described for implementation during subsequent planned outages at Zion Station. This final report describes the recommended conceptual designs and planning mechanism and assesses their impact upon future outages. Their effect on savings in refueling time, labor, and radiation exposure is discussed. The estimated economic payoff for these concepts was found to be of such significance that an additional phase of the program is warranted. During this extended phase, a more detailed engineering study should be undertaken to determine the cost of implementation along with more specific estimates of the benefits for PWR plants already in operation or under construction.

  19. Factors influencing aircraft ground handling performance

    Science.gov (United States)

    Yager, T. J.

    1983-01-01

    Problems associated with aircraft ground handling operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research results from tests with instrumented ground vehicles and aircraft, and aircraft wet runway accident investigation are summarized to indicate the effects of different aircraft, tire, and runway parameters. Several promising means are described for improving tire/runway water drainage capability, brake system efficiency, and pilot training to help optimize aircraft traction performance on wet runways.

  20. Interval of Routine Maintenance and Maintenance Performance: A Literature Review

    Directory of Open Access Journals (Sweden)

    Au-Yong Cheong Peng

    2016-01-01

    Full Text Available In high-rise residential buildings, the quality of facilities management services is significant to the normal operation of the facilities. Unfortunately, lack of concern towards building maintenance, especially preventive maintenance, happens in domestic housing industry in Malaysia. Majority of the maintenance operations of condominiums suffer from lack of planning, lack of proactive maintenance plan, and lack of proper implementation. Thus, this paper reviews the implementation of preventive maintenance strategy, routine maintenance in specific. An extensive review of literature published in 1987 to 2014 is performed for the purpose of this research. The publications are sourced from journal articles, conference proceedings and books. The literature analysis confirms that the routine maintenance of facilities and building services is vital and it can be influential towards the maintenance performance. Subsequently, a theoretical framework is developed, which shows the relationship between routine maintenance of building facilities & services and maintenance performance. The building facilities & services are divided into two categories. They are essential facilities & services that ensure the safety, health, habitability, and operability of buildings; while value-added facilities & services deal with property value, return on investment, and quality living of buildings. Based on the findings, a future research is proposed, which aims to identify the appropriate routine of maintenance for the facilities and services in high-rise residential buildings to improve the maintenance performance.

  1. 飞机襟翼控制系统故障分析及改进设计%Fault Analysis and Improvement Design for Aircraft Flap Control System

    Institute of Scientific and Technical Information of China (English)

    张晓燕; 张巍

    2013-01-01

    针对某型飞机襟翼操纵开关操作不便,并且无法完全实现单电机收放襟翼的问题,重新布置了襟翼操纵开关位置,分析襟翼控制系统的故障,并进行了改进设计,实现了单套控制电路和电机收放襟翼的目的,提高了襟翼操纵系统的可靠性。设计改进得到了飞行试验的验证。%In view of the problems that the lfap control switch is operated inconveniently and a single electrical motor does not realize lfap retraction or extension in some aircrafts, this paper rearranges the layout of lfap control switch, analyses the foult and improves the design of the lfap control system ,realizes the object of retraction/extension the lfap though a single control circuit and motor,and improves the reliability of the lfap control system. Design improvement is veriifed by lfight test.

  2. Turboprop aircraft against terrorism: a SWOT analysis of turboprop aircraft in CAS operations

    Science.gov (United States)

    Yavuz, Murat; Akkas, Ali; Aslan, Yavuz

    2012-06-01

    Today, the threat perception is changing. Not only for countries but also for defence organisations like NATO, new threat perception is pointing terrorism. Many countries' air forces become responsible of fighting against terorism or Counter-Insurgency (COIN) Operations. Different from conventional warfare, alternative weapon or weapon systems are required for such operatioins. In counter-terrorism operations modern fighter jets are used as well as helicopters, subsonic jets, Unmanned Aircraft Systems (UAS), turboprop aircraft, baloons and similar platforms. Succes and efficiency of the use of these platforms can be determined by evaluating the conditions, the threats and the area together. Obviously, each platform has advantages and disadvantages for different cases. In this research, examples of turboprop aircraft usage against terrorism and with a more general approach, turboprop aircraft for Close Air Support (CAS) missions from all around the world are reviewed. In this effort, a closer look is taken at the countries using turboprop aircraft in CAS missions while observing the fields these aircraft are used in, type of operations, specifications of the aircraft, cost and the maintenance factors. Thus, an idea about the convenience of using these aircraft in such operations can be obtained. A SWOT analysis of turboprop aircraft in CAS operations is performed. This study shows that turboprop aircraft are suitable to be used in counter-terrorism and COIN operations in low threat environment and is cost benefical compared to jets.

  3. Aircraft conceptual design modelling incorporating reliability and maintainability predictions

    OpenAIRE

    Vaziry-Zanjany , Mohammad Ali (F)

    1996-01-01

    A computer assisted conceptual aircraft design program has been developed (CACAD). It has an optimisation capability, with extensive break-down in maintenance costs. CACAD's aim is to optimise the size, and configurations of turbofan-powered transport aircraft. A methodology was developed to enhance the reliability of current aircraft systems, and was applied to avionics systems. R&M models of thermal management were developed and linked with avionics failure rate and its ma...

  4. Influence of environmental factors on corrosion damage of aircraft structure

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Corrosion is one of the important structural integrity concerns of aging aircraft, and it is estimated that a significant portion of airframe maintenance budgets is directed towards corrosion-related problems for both military and commercial aircraft. In order to better understand how environmental factors influence the corrosion damage initiation and propagation on aircraft structure and to predict pre-corrosion test pieces of fatigue life and structural integrity of an effective approach, this paper uses ...

  5. Analysis on occupational hearing loss of noise-exposed workers in an aircraft maintenance engineering company%某飞机维修工程公司噪声作业人员听力损伤分析

    Institute of Scientific and Technical Information of China (English)

    张君

    2013-01-01

    [Objective]To investigate the noise-exposed workers in an aircraft maintenance engineering company, to analyze their hearing impairment status, and put forward suggestions for prevention of occupational hearing loss and occupational noise deafness. [Methods] A total of 1 067 noise-exposed workers were recruited as noise group and 111 without noise exposure as control group. MM-622 pure tone audiometer by the zero-level correction was adopted for pure tone air conduction checks at 0.5, 1.0, 2.0, 3. 0, 4.0, 6.0 kHz on ears of workers. Assessment standards of hearing impairment: speech frequency at 0. 5, 1.0, 2.0 kHz in average >25dB, high-frequency at 3.0, 4.0, 6.0 kHz respectively ≥30 dB. [Results] A total of 1 067 workers (2 134 ears) were investigated, 345 (647 ears) had hearing impairment, the prevalence was 32. 33% . High-frequency hearing loss occurred on 320 workers (614 ears) , speech frequency hearing loss on 25 workers (33 ears). Of 111 workers in control group, 4 workers (6 ears) had hearing impairment, all were high-frequency hearing loss, the prevalence was 3. 60%. The prevalence of hearing impairment of noise group was obviously higher than that of control group, with significant difference ( x2 = 39. 80,P <0.01). [Conclusion] Noise influences the high-frequency hearing threshold of workers with exposure . And the risk of hearing loss rate inceases with the extending of service length. It is suggested to strengthen personal protection, to establish health records and control occupational noise deafness.%目的 对某飞机维修工程公司噪声作业人员进行调查,分析该公司噪声作业人员的听力损伤现状,以期对预防职业性听力损伤和职业性噪声聋提出建议.方法 设噪声作业组1067人,非噪声接触人员111人为对照组,均使用丹麦产MM-622型纯音听力计(经零级校正),对两组人员双耳0.5、1.0、2.0、3.0、4.0、6.0 kHz的纯音气导进行检查,听力损伤的评定标准:语频听损以0

  6. Toward improved durability in advanced aircraft engine hot sections; Proceedings of the Thirty-third ASME International Gas Turbine and Aeroengine Congress and Exposition, Amsterdam, Netherlands, June 5-9, 1988

    Science.gov (United States)

    Sokolowski, Daniel E. (Editor)

    1988-01-01

    The present conference on durability improvement methods for advanced aircraft gas turbine hot-section components discusses NASA's 'HOST' project, advanced high-temperature instrumentation for hot-section research, the development and application of combustor aerothermal models, and the evaluation of a data base and numerical model for turbine heat transfer. Also discussed are structural analysis methods for gas turbine hot section components, fatigue life-prediction modeling for turbine hot section materials, and the service life modeling of thermal barrier coatings for aircraft gas turbine engines.

  7. Maintenance Reliability Program as Essential Prerequisite of Flight Safety

    OpenAIRE

    Željko Marušić; Izidor Alfirević; Omer Pita

    2009-01-01

    This article is dealing with airline industry standards regarding reliability reporting and with practical aspects of reliability program deployment within an operator’s organization. Reliability program is a tool for monitoring the effectiveness of aircraft maintenance program. Apart from being an effective tool for maintenance program development, the reliability program can bring to light flaws in aircraft design, discrepant operational procedures, discrepancies in line and base maintenanc...

  8. Maintenance Reliability Program as Essential Prerequisite of Flight Safety

    OpenAIRE

    Željko Marušić; Izidor Alfirević; Omer Pita

    2009-01-01

    This article is dealing with airline industry standards regarding reliability reporting and with practical aspects of reliability program deployment within an operator’s organization. Reliability program is a tool for monitoring the effectiveness of aircraft maintenance program. Apart from being an effective tool for maintenance program development, the reliability program can bring to light flaws in aircraft design, discrepant operational procedures, discrepancies in line and base maintenanc...

  9. Slotted Aircraft Wing

    Science.gov (United States)

    McLean, James D. (Inventor); Witkowski, David P. (Inventor); Campbell, Richard L. (Inventor)

    2006-01-01

    A swept aircraft wing includes a leading airfoil element and a trailing airfoil element. At least one full-span slot is defined by the wing during at least one transonic condition of the wing. The full-span slot allows a portion of the air flowing along the lower surface of the leading airfoil element to split and flow over the upper surface of the trailing airfoil element so as to achieve a performance improvement in the transonic condition.

  10. 14 CFR 43.10 - Disposition of life-limited aircraft parts.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Disposition of life-limited aircraft parts. 43.10 Section 43.10 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE, REBUILDING, AND ALTERATION § 43.10 Disposition...

  11. Financial incentives to improve adherence to anti-psychotic maintenance medication in non-adherent patients - a cluster randomised controlled trial (FIAT

    Directory of Open Access Journals (Sweden)

    Firn Mike

    2009-09-01

    Full Text Available Abstract Background Various interventions have been tested to achieve adherence to anti-psychotic maintenance medication in non-adherent patients with psychotic disorders, and there is no consistent evidence for the effectiveness of any established intervention. The effectiveness of financial incentives in improving adherence to a range of treatments has been demonstrated; no randomised controlled trial however has tested the use of financial incentives to achieve medication adherence for patients with psychotic disorders living in the community. Methods/Design In a cluster randomised controlled trial, 34 mental health teams caring for difficult to engage patients in the community will be randomly allocated to either the intervention group, where patients will be offered a financial incentive for each anti-psychotic depot medication they receive over a 12 month period, or the control group, where all patients will receive treatment as usual. We will recruit 136 patients with psychotic disorders who use these services and who have problems adhering to antipsychotic depot medication, although all conventional methods to achieve adherence have been tried. The primary outcome will be adherence levels, and secondary outcomes are global clinical improvement, number of voluntary and involuntary hospital admissions, number of attempted and completed suicides, incidents of physical violence, number of police arrests, number of days spent in work/training/education, subjective quality of life and satisfaction with medication. We will also establish the cost effectiveness of offering financial incentives. Discussion The study aims to provide new evidence on the effectiveness and cost effectiveness of offering financial incentives to patients with psychotic disorders to adhere to antipsychotic maintenance medication. If financial incentives improve adherence and lead to better health and social outcomes, they may be recommended as one option to improve the

  12. Improvement of the military academy education system for aeronautics students using the flying laboratory

    Directory of Open Access Journals (Sweden)

    Slobodan N. Stupar

    2013-02-01

    Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 This paper describes a proposal to improve the educational process of students of the Military Academy to support the maintenance process of the Serbian Army aircraft based on the introduction of objects in flight test aircraft. It is particularly emphasized the importance of establishing airline laboratories with basic characteristics of the test-measuring equipment that is necessary to integrate the aircraft to perform a practical test of an aircraft in flight. The formation of aircraft laboratories would form a very strong didactic tool, which provides for optimal synthesis of theory and practice. This concept of improving the educational process would be substantially affected the awareness of the necessity of working together and put together all the research capacity of scientific institutions in the Ministry of Defence of the Republic of Serbia.

  13. Aircraft recognition and pose estimation

    Science.gov (United States)

    Hmam, Hatem; Kim, Jijoong

    2000-05-01

    This work presents a geometry based vision system for aircraft recognition and pose estimation using single images. Pose estimation improves the tracking performance of guided weapons with imaging seekers, and is useful in estimating target manoeuvres and aim-point selection required in the terminal phase of missile engagements. After edge detection and straight-line extraction, a hierarchy of geometric reasoning algorithms is applied to form line clusters (or groupings) for image interpretation. Assuming a scaled orthographic projection and coplanar wings, lateral symmetry inherent in the airframe provides additional constraints to further reject spurious line clusters. Clusters that accidentally pass all previous tests are checked against the original image and are discarded. Valid line clusters are then used to deduce aircraft viewing angles. By observing that the leading edges of wings of a number of aircraft of interest are within 45 to 65 degrees from the symmetry axis, a bounded range of aircraft viewing angles can be found. This generic property offers the advantage of not requiring the storage of complete aircraft models viewed from all aspects, and can handle aircraft with flexible wings (e.g. F111). Several aircraft images associated with various spectral bands (i.e. visible and infra-red) are finally used to evaluate the system's performance.

  14. 14 CFR 65.107 - Repairman certificate (light-sport aircraft): Eligibility, privileges, and limits.

    Science.gov (United States)

    2010-01-01

    ... certificate (light-sport aircraft) with a maintenance rating (i) Meet the requirements of paragraph (a)(1) of... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Repairman certificate (light-sport aircraft... CREWMEMBERS Repairmen § 65.107 Repairman certificate (light-sport aircraft): Eligibility, privileges, and...

  15. The effect of current military maintenance practices and regulations on the implementation of Integrated Vehicle Health Management technology

    OpenAIRE

    Esperon Miguez, Manuel; John, Philip; Ian K. Jennions

    2012-01-01

    Health monitoring tools can be used to diagnose failures and estimate the remaining useful life of certain components, generating information that can be used to improve the management of logistics and maintenance activities in what is known as Integrated Vehicle Health Management (IVHM). The work presented here analyzes the effect of military practices and regulations on the benefits that can be expected from installing health monitoring tools on military aircraft. The findings on the impact...

  16. Lenalidomide, melphalan, and prednisone, followed by lenalidomide maintenance, improves health-related quality of life in newly diagnosed multiple myeloma patients aged 65 years or older: results of a randomized phase III trial.

    Science.gov (United States)

    Dimopoulos, Meletios A; Delforge, Michel; Hájek, Roman; Kropff, Martin; Petrucci, Maria T; Lewis, Philip; Nixon, Annabel; Zhang, Jingshan; Mei, Jay; Palumbo, Antonio

    2013-05-01

    The MM-015 trial assessed the effect of lenalidomide-based therapy on health-related quality of life. Patients (n=459) with newly diagnosed multiple myeloma aged 65 years or over were randomized 1:1:1 to nine 4-week cycles of lenalidomide, melphalan, and prednisone, followed by lenalidomide maintenance; or lenalidomide, melphalan, and prednisone, or melphalan and prednisone, with no maintenance therapy. Patients completed health-related quality of life questionnaires at baseline, after every third treatment cycle, and at treatment end. Health-related quality of life improved in all treatment groups during induction therapy. Patients receiving lenalidomide maintenance had the most pronounced improvements, Global Health Status/Quality of Life (Plife domains. More patients receiving lenalidomide maintenance achieved minimal important differences (Pimproves health-related quality of life in patients with newly diagnosed multiple myeloma. (Clinicaltrials.gov identifier NCT00405756).

  17. Maintenance Therapy in IBD

    Science.gov (United States)

    ... Help Center Home > Resources > Maintenance Therapy Go Back Maintenance Therapy Email Print + Share The term "maintenance therapy" ... are referred to as "maintenance therapies." Why is Maintenance Therapy Needed in IBD? Both Crohn's disease and ...

  18. Maintenance Therapy in IBD

    Science.gov (United States)

    ... Help Center Home > Resources > Maintenance Therapy Go Back Maintenance Therapy Email Print + Share The term "maintenance therapy" ... are referred to as "maintenance therapies." Why is Maintenance Therapy Needed in IBD? Both Crohn's disease and ...

  19. Low Noise Aircraft Selection Based on Improved Grey Relational Analysis of B-Mode%基于改进灰色B型关联度的低噪声飞机选型

    Institute of Scientific and Technical Information of China (English)

    李东亚; 胡荣; 江超; 战绪仁

    2015-01-01

    为有效缓解飞机噪声的影响,选择出噪声值更小的机型,针对国内某机场噪声监测数据特点,选用兼具相近性与相似性的灰色B型关联分析法对该机场一个月内同一航班六种机型噪声监测数据进行分析.根据研究问题需要,设计无量纲化处理方法,优化噪声监测数据权重,改进灰色B型关联度方法,计算各机型噪声数据与最优数据的关联度,优选出满足条件的低噪声机型.结果表明,改进后灰色B型关联度方法适用于低噪声飞机选型问题,分析结果符合实际,其中B733机型最能满足该机场低噪声的条件.%To alleviate the influence of aircraft noise effectively and choose the lower noise aircraft types, the noise monitoring data of six kinds of aircrafts for the same flight at a domestic airport were analyzed using the grey relational analysis of B-mode which has both proximity and similarity. In this analysis, a dimensionless processing method was designed to optimize the weight of the noise monitoring data and improve the grey relational analysis of B-mode. The correlations between the aircraft noise data of different type of aircrafts and the optimal noise data were calculated and the low noise aircraft type was selected. The results show that the improved grey relational analysis of B-mode is suitable for the selection of low noise aircraft, and the analysis results are consistent with the actual data. In addition, the B733 aircraft type is the best in satisfying the condition of low noise at the airport.

  20. The Comparison of the Effectiveness of Risperidone and Fluoxetine in Combination with Impulse Control Group Therapy on Improving of Impulsivity, and Relapse in Heroin Crack Addicts under Methadone Maintenance Therapy

    OpenAIRE

    Rohoallah Hadadi; Hamid reza Fathinaz; Mehdi Karimi; Saeed Akbari; Nafiseh Soltannejad

    2013-01-01

    Aim: The aim of the study was to compare the effectiveness of Risperidone and Fluoxetine in combination with impulse control group therapy on improving of impulsivity, and relapse in heroin crack addicts under methadone maintenance therapy. Method: In a semi-experimental study, 39 heroin crack addicts who were under Methadone maintenance treatment selected of addiction withdrawal centers in Tehran. The selected sample was randomly assigned to three groups. First group was under (Risperidone 1...

  1. Maintenance Decision Based on Data Fusion of Aero Engines

    Directory of Open Access Journals (Sweden)

    Huawei Wang

    2013-01-01

    Full Text Available Maintenance has gained a great importance as a support function for ensuring aero engine reliability and availability. Cost-effectiveness and risk control are two basic criteria for accurate maintenance. Given that aero engines have much condition monitoring data, this paper presents a new condition-based maintenance decision system that employs data fusion for improving accuracy of reliability evaluation. Bayesian linear model has been applied, so that the performance degradation evaluation of aero engines could be realized. A reliability evaluation model has been presented based on gamma process, which achieves the accurate evaluation by information fusion. In reliability evaluation model, the shape parameter is estimated by the performance degradation evaluation result, and the scale parameter is estimated by failure, inspection, and repair information. What is more, with such reliability evaluation as input variables and by using particle swarm optimization (PSO, a stochastic optimization of maintenance decision for aircraft engines has been presented, in which the effectiveness and the accuracy are demonstrated by a numerical example.

  2. Modeling and Simulation of Power Distribution System in More Electric Aircraft

    Directory of Open Access Journals (Sweden)

    Zhangang Yang

    2015-01-01

    Full Text Available The More Electric Aircraft concept is a fast-developing trend in modern aircraft industry. With this new concept, the performance of the aircraft can be further optimized and meanwhile the operating and maintenance cost will be decreased effectively. In order to optimize the power system integrity and have the ability to investigate the performance of the overall system in any possible situations, one accurate simulation model of the aircraft power system will be very helpful and necessary. This paper mainly introduces a method to build a simulation model for the power distribution system, which is based on detailed component models. The power distribution system model consists of power generation unit, transformer rectifier unit, DC-DC converter unit, and DC-AC inverter unit. In order to optimize the performance of the power distribution system and improve the quality of the distributed power, a feedback control network is designed based on the characteristics of the power distribution system. The simulation result indicates that this new simulation model is well designed and it works accurately. Moreover, steady state performance and transient state performance of the model can fulfill the requirements of aircraft power distribution system in the realistic application.

  3. Interrelation of the Problems of the Aircraft Fleet Development and the Improvement of the Air Traffic Control System

    Directory of Open Access Journals (Sweden)

    Mihail Yurevich Smurov

    2016-07-01

    Full Text Available In the article the problems of air transport have been identified. Among these problems, the congestion of airports and airspace and the need for development and modernization of the airport network are of particular importance. In this regard, the authors consider the improvement of the air traffic control system (ATC system by integrating existing ATC systems into a single global system with the use of unified international standards, rules and procedures. The article also specifies the main indicators characterizing the dynamics of the development of the air transport industry in Russia and abroad.

  4. Practical Voice Recognition for the Aircraft Cockpit Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal responds to the urgent need for improved pilot interfaces in the modern aircraft cockpit. Recent advances in aircraft equipment bring tremendous...

  5. Advanced Aerostructural Optimization Techniques for Aircraft Design

    OpenAIRE

    Yingtao Zuo; Pingjian Chen; Lin Fu; Zhenghong Gao; Gang Chen

    2015-01-01

    Traditional coupled aerostructural design optimization (ASDO) of aircraft based on high-fidelity models is computationally expensive and inefficient. To improve the efficiency, the key is to predict aerostructural performance of the aircraft efficiently. The cruise shape of the aircraft is parameterized and optimized in this paper, and a methodology named reverse iteration of structural model (RISM) is adopted to get the aerostructural performance of cruise shape efficiently. A new mathematic...

  6. Tree canopy light interception estimates in almond and a walnut orchards using ground, low flying aircraft, and satellite based methods to improve irrigation scheduling programs.

    Science.gov (United States)

    Rosecrance, R. C.; Johnson, L.; Soderstrom, D.

    2016-12-01

    Canopy light interception is a main driver of water use and crop yield in almond and walnut production. Fractional green canopy cover (Fc) is a good indicator of light interception and can be estimated remotely from satellite using the normalized difference vegetation index (NDVI) data. Satellite-based Fc estimates could be used to inform crop evapotranspiration models, and hence support improvements in irrigation evaluation and management capabilities. Satellite estimates of Fc in almond and walnut orchards, however, need to be verified before incorporating them into irrigation scheduling or other crop water management programs. In this study, Landsat-based NDVI and Fc from NASA's Satellite Irrigation Management Support (SIMS) were compared with four estimates of canopy cover: 1. light bar measurement, 2. in-situ and image-based dimensional tree-crown analyses, 3. high-resolution NDVI data from low flying aircraft, and 4. orchard photos obtained via Google Earth and processed by an Image J thresholding routine. Correlations between the various estimates are discussed.

  7. Tree Canopy Light Interception Estimates in Almond and a Walnut Orchards Using Ground, Low Flying Aircraft, and Satellite Based Methods to Improve Irrigation Scheduling Programs

    Science.gov (United States)

    Rosecrance, Richard C.; Johnson, Lee; Soderstrom, Dominic

    2016-01-01

    Canopy light interception is a main driver of water use and crop yield in almond and walnut production. Fractional green canopy cover (Fc) is a good indicator of light interception and can be estimated remotely from satellite using the normalized difference vegetation index (NDVI) data. Satellite-based Fc estimates could be used to inform crop evapotranspiration models, and hence support improvements in irrigation evaluation and management capabilities. Satellite estimates of Fc in almond and walnut orchards, however, need to be verified before incorporating them into irrigation scheduling or other crop water management programs. In this study, Landsat-based NDVI and Fc from NASA's Satellite Irrigation Management Support (SIMS) were compared with four estimates of canopy cover: 1. light bar measurement, 2. in-situ and image-based dimensional tree-crown analyses, 3. high-resolution NDVI data from low flying aircraft, and 4. orchard photos obtained via Google Earth and processed by an Image J thresholding routine. Correlations between the various estimates are discussed.

  8. Behaviour change intervention to improve shared toilet maintenance and cleanliness in urban slums of Dhaka: a cluster-randomised controlled trial.

    Science.gov (United States)

    Alam, Mahbub-Ul; Winch, Peter J; Saxton, Ronald E; Nizame, Fosiul A; Yeasmin, Farzana; Norman, Guy; Masud, Abdullah-Al; Begum, Farzana; Rahman, Mahbubur; Hossain, Kamal; Layden, Anita; Unicomb, Leanne; Luby, Stephen P

    2017-08-01

    Shared toilets in urban slums are often unclean and poorly maintained, discouraging consistent use and thereby limiting impacts on health and quality of life. We developed behaviour change interventions to support shared toilet maintenance and improve user satisfaction. We report the intervention effectiveness on improving shared toilet cleanliness. We conducted a cluster-randomised controlled trial among users of 1226 shared toilets in 23 Dhaka slums. We assessed baseline toilet cleanliness in January 2015. The six-month intervention included provision of hardware (bin for solid waste, 4 l flushing bucket, 70 l water reservoir), and behaviour change communication (compound meetings, interpersonal household sessions, signs depicting rules for toilet use). We estimated the adjusted difference in difference (DID) to assess outcomes and accounted for clustering effects using generalised estimating equations. Compared to controls, intervention toilets were more likely to have water available inside toilet cubicles (DID: +4.7%, 95% CI: 0.2, 9.2), access to brush/broom for cleaning (DID: +8.4%, 95% CI: 2, 15) and waste bins (DID: +63%, 95% CI: 59, 66), while less likely to have visible faeces inside the pan (DID: -13%, 95% CI: -19, -5), the smell of faeces (DID: -7.6%, 95% CI: -14, -1.3) and household waste inside the cubicle (DID: -4%, 95% CI: -7, -1). In one of few efforts to promote shared toilet cleanliness, intervention compounds were significantly more likely to have cleaner toilets after six months. Future research might explore how residents can self-finance toilet maintenance, or employ mass media to reduce per-capita costs of behaviour change. © 2017 John Wiley & Sons Ltd.

  9. Improving Fleet and Industrial Supply Center, Sigonella, Italy: Detachment Bahrain’s Ship Maintenance Contracts in Southwest Asia

    Science.gov (United States)

    2011-05-16

    Project Sponsor: CAPT Chris Ray Black/Green Belt: CDR Mike Ryan Business Impact ($) KAIZEN / Rapid Improvement Event The expected impacts of this...Availability Contracts Project Methodology: DMAIC DFSS Kaizen Project Plan—list planned dates for each DMAIC phase Kaizen start and end dates...Initial Plan of Action for Kaizen Week 1) List and quantify elements that make the Big X metrics; 2) Capture the current competition categories into which

  10. Improvement of Chicken Primordial Germ Cell Maintenance In Vitro by Blockade of the Aryl Hydrocarbon Receptor Endogenous Activity.

    Science.gov (United States)

    Pérez Sáez, Juan M; Bussmann, Leonardo E; Barañao, J Lino; Bussmann, Ursula A

    2016-06-01

    Primordial germ cells (PGCs) are the undifferentiated progenitors of gametes. Germline competent PGCs can be developed as a cell-based system for genetic modification in chickens, which provides a valuable tool for transgenic technology with both research and industrial applications. This implies manipulation of PGCs, which, in recent years, encouraged a lot of research focused on the study of PGCs and the way of improving their culture. The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that besides mediating toxic responses to environmental contaminants plays pivotal physiological roles in various biological processes. Since a novel compound that acts as an antagonist of this receptor has been reported to promote expansion of hematopoietic stem cells, we conducted the present study with the aim of determining whether addition of an established AHR antagonist to the standard culture medium used nowadays for in vitro chicken PGCs culture improves ex vivo expansion. We have found that addition of α-naphthoflavone in culture medium promotes the amplification of undifferentiated cells and that this effect is exerted by the blockade of AHR action. Our results constitute the first report of the successful use of a readily available AHR antagonist to improve avian PGCs expansion, and they further extend the knowledge of the effects of AHR modulation in undifferentiated cells.

  11. Emerging nondestructive inspection methods for aging aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Beattie, A; Dahlke, L; Gieske, J [and others

    1994-01-01

    This report identifies and describes emerging nondestructive inspection (NDI) methods that can potentially be used to inspect commercial transport and commuter aircraft for structural damage. The nine categories of emerging NDI techniques are: acoustic emission, x-ray computed tomography, backscatter radiation, reverse geometry x-ray, advanced electromagnetics, including magnetooptic imaging and advanced eddy current techniques, coherent optics, advanced ultrasonics, advanced visual, and infrared thermography. The physical principles, generalized performance characteristics, and typical applications associated with each method are described. In addition, aircraft inspection applications are discussed along with the associated technical considerations. Finally, the status of each technique is presented, with a discussion on when it may be available for use in actual aircraft maintenance programs. It should be noted that this is a companion document to DOT/FAA/CT-91/5, Current Nondestructive Inspection Methods for Aging Aircraft.

  12. 14 CFR 125.247 - Inspection programs and maintenance.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Inspection programs and maintenance. 125.247 Section 125.247 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... CAPACITY OF 6,000 POUNDS OR MORE; AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Maintenance §...

  13. Improved ship maintenance cost case adaptation model%改进的舰船维修费案例调整模型

    Institute of Scientific and Technical Information of China (English)

    訾书宇; 魏汝祥; 蒋铁军; 谢力

    2012-01-01

    In order to enhance the adaptation effect of ship maintenance cost case, an improved ship maintenance cost case adaptation model is proposed according to the modeling process of producing adaptation knowledge, reducing adaptation knowledge and reasoning adaptation knowledge. In this model, the ship maintenance cost case adaptation knowledge is produced by the direct similarity sets and indirect similarity sets of target cases based on the Policastro's format; towards the problems that correlation and redundancy exist in the above adaptation knowledge, or the knowledge is too large to deal with, an improved rule reduction method is put forward which can both reduce the above knowledge effectively and measure their importance accurately, in addition, the algorithm for rule reduction is given; in order to improve the performance of knowledge reasoning, least square support vector machine (LSSVM) which has strong generalization power and perfect learning power is used to establish the ship maintenance cost case adaptation knowledge reasoning model, and the parameters of model are optimized according to genetic algorithm (GA) and cross-validation method. Example analysis reveals that, compared with other case adaptation models, the adaptation accuracy of the proposed model is far better, so the proposed model is scientific and valid.%为提高舰船维修费案例的调整效果,遵循着调整知识产生、调整知识约简和调整知识推理的建模过程,提出了一种改进的舰船维修费案例调整模型.在该模型中,采用Policastro的重构方式,利用目标案例的直接和间接相似案例集,产生舰船维修费案例的调整知识;针对调整知识中可能存在冗余、相关性、知识量过于庞大不便于推理等问题,提出了一种既能有效约简调整知识、又能准确衡量调整知识重要度的改进规则约简方法,并给出了具体的实现算法;为提高知识推理的效率,采用具有强泛化能力和

  14. Impact of Advanced Propeller Technology on Aircraft/Mission Characteristics of Several General Aviation Aircraft

    Science.gov (United States)

    Keiter, I. D.

    1982-01-01

    Studies of several General Aviation aircraft indicated that the application of advanced technologies to General Aviation propellers can reduce fuel consumption in future aircraft by a significant amount. Propeller blade weight reductions achieved through the use of composites, propeller efficiency and noise improvements achieved through the use of advanced concepts and improved propeller analytical design methods result in aircraft with lower operating cost, acquisition cost and gross weight.

  15. Financial incentives to improve adherence to antipsychotic maintenance medication in non-adherent patients: a cluster randomised controlled trial.

    Science.gov (United States)

    Priebe, Stefan; Bremner, Stephen A; Lauber, Christoph; Henderson, Catherine; Burns, Tom

    2016-09-01

    Poor adherence to long-term antipsychotic injectable (LAI) medication in patients with psychotic disorders is associated with a range of negative outcomes. No psychosocial intervention has been found to be consistently effective in improving adherence. To test whether or not offering financial incentives is effective and cost-effective in improving adherence and to explore patient and clinician experiences with such incentives. A cluster randomised controlled trial with economic and nested qualitative evaluation. The intervention period lasted for 12 months with 24 months' follow-up. The unit of randomisation was mental health teams in the community. Community teams in secondary mental health care. Patients with a diagnosis of schizophrenia, schizoaffective psychosis or bipolar illness, receiving ≤ 75% of their prescribed LAI medication. In total, 73 teams with 141 patients (intervention n = 78 and control n = 63) were included. Participants in the intervention group received £15 for each LAI medication. Patients in the control group received treatment as usual. adherence to LAI medication (the percentage of received out of those prescribed). percentage of patients with at least 95% adherence; clinical global improvement; subjective quality of life; satisfaction with medication; hospitalisation; adverse events; and costs. Qualitative evaluation: semistructured interviews with patients in the intervention group and their clinicians. outcome data were available for 131 patients. Baseline adherence was 69% in the intervention group and 67% in the control group. During the intervention period, adherence was significantly higher in the intervention group than in the control group (85% vs. 71%) [adjusted mean difference 11.5%, 95% confidence interval (CI) 3.9% to 19.0%; p = 0.003]. Secondary outcome: patients in the intervention group showed statistically significant improvement in adherence of at least 95% (adjusted odds ratio 8.21, 95% CI 2.00 to 33

  16. The Benefits and Costs of Stealth From The Aircraft Designer’s Viewpoint

    Directory of Open Access Journals (Sweden)

    R. Whitford

    2000-01-01

    Full Text Available The reduction or other control of an aircraft’s radar, infrared, visual and acoustic signatures can greatly improve its survival, resulting in improved weapons` effectiveness. Although radar and infrared stealth are important, other aspects of low observability (i.e. acouctic and visual cannot be ignored. However, this paper, for reasons of brevity, focuses on control of radar and infrared signatures. The topics of: benefits of signature control; contributions of an aircraft to its radar cross section (RCS and infrared (IR signature; methods to reduce RCS and IR signature; penalties/costs of signature reduction, in terms of performance, volume, weight and maintenance; and use of radar absorbing materials are addressed. The conclusion is that while signature control is important, there are penalties to be paid. Signature reduction has become yet another factor to be concidered in the series of compromises made during aircraft design trade-offs.

  17. Protein supplements after weight loss do not improve weight maintenance compared with recommended dietary protein intake despite beneficial effects on appetite sensation and energy expenditure

    DEFF Research Database (Denmark)

    Kjølbæk, Louise; Sørensen, Lone Brinkmann; Søndertoft, Nadja Buus

    2017-01-01

    Background: High-protein diets increase weight loss (WL) during energy restriction; therefore, it has been suggested that additional protein intake may improve weight maintenance (WM) after WL.Objective: We investigated the effect of protein supplements from either whey with or without calcium......+: 2.19 ± 4.6 kg; whey: 2.01 ± 4.6 kg; soy: 1.76 ± 4.7 kg; and control: 2.23 ± 3.8 kg; P = 0.96), fat mass regains (whey+: 0.46 ± 4.5 kg; whey: 0.11 ± 4.1 kg; soy: 0.15 ± 4.1 kg; and control: 0.54 ± 3.3 kg; P = 0.96), or improvements in lean body mass (whey+: 1.87 ± 1.7 kg; whey: 1.94 ± 1.3 kg; soy: 1......-sensation profile.Conclusion: Protein supplementation does not result in improved WM success, or blood biochemistry after WL compared with the effects of normal dietary protein intake (0.8-1.0 g · kg(-1) · d(-1)). This trial was registered at clinicaltrials.gov as NCT01561131....

  18. Is Maintenance Therapy for Everyone?

    Science.gov (United States)

    Nooka, Ajay K; Lonial, Sagar

    2016-08-01

    Although myeloma remains an incurable disease among majority of myeloma patients, the prognosis has significantly improved after the introduction of novel agents. While more agents are being explored for their anti-myeloma activity, the more familiar agents with a better tolerability profile have been tested in the maintenance arena. Lenalidomide and bortezomib so far have shown promise as effective maintenance agents in prolonging PFS, and also OS in some studies. The current review aims at describing the clinical data supporting various maintenance therapies and also at providing some clarity to a few concerns associated with maintenance therapies.

  19. Aircraft Electric Secondary Power

    Science.gov (United States)

    1983-01-01

    Technologies resulted to aircraft power systems and aircraft in which all secondary power is supplied electrically are discussed. A high-voltage dc power generating system for fighter aircraft, permanent magnet motors and generators for aircraft, lightweight transformers, and the installation of electric generators on turbine engines are among the topics discussed.

  20. Reliability Centered Maintenance - Methodologies

    Science.gov (United States)

    Kammerer, Catherine C.

    2009-01-01

    Journal article about Reliability Centered Maintenance (RCM) methodologies used by United Space Alliance, LLC (USA) in support of the Space Shuttle Program at Kennedy Space Center. The USA Reliability Centered Maintenance program differs from traditional RCM programs because various methodologies are utilized to take advantage of their respective strengths for each application. Based on operational experience, USA has customized the traditional RCM methodology into a streamlined lean logic path and has implemented the use of statistical tools to drive the process. USA RCM has integrated many of the L6S tools into both RCM methodologies. The tools utilized in the Measure, Analyze, and Improve phases of a Lean Six Sigma project lend themselves to application in the RCM process. All USA RCM methodologies meet the requirements defined in SAE JA 1011, Evaluation Criteria for Reliability-Centered Maintenance (RCM) Processes. The proposed article explores these methodologies.

  1. Opportune maintenance and predictive maintenance decision support

    OpenAIRE

    Thomas, Edouard; Levrat, Eric; Iung, Benoît; Cocheteux, Pierre

    2009-01-01

    International audience; Conventional maintenance strategies on a single component are being phased out in favour of more predictive maintenance actions. These new kinds of actions are performed in order to control the global performances of the whole industrial system. They are anticipative in nature, which allows a maintenance expert to consider non-already-planned maintenance actions. Two questions naturally emerge: when to perform a predictive maintenance action; how a maintenance expert c...

  2. The Comparison of the Effectiveness of Risperidone and Fluoxetine in Combination with Impulse Control Group Therapy on Improving of Impulsivity, and Relapse in Heroin Crack Addicts under Methadone Maintenance Therapy

    Directory of Open Access Journals (Sweden)

    Rohoallah Hadadi

    2013-05-01

    Full Text Available Aim: The aim of the study was to compare the effectiveness of Risperidone and Fluoxetine in combination with impulse control group therapy on improving of impulsivity, and relapse in heroin crack addicts under methadone maintenance therapy. Method: In a semi-experimental study, 39 heroin crack addicts who were under Methadone maintenance treatment selected of addiction withdrawal centers in Tehran. The selected sample was randomly assigned to three groups. First group was under (Risperidone 1 mg daily, impulse control group therapy for 8 sessions of 90 minutes, and methadone maintenance treatment, the second group was under (Fluoxetine 20 mg daily, impulse control group therapy for 8 sessions of 90 minutes, and methadone maintenance therapy, and the third group was under (impulse control group therapy for 8 sessions of 90 minutes, and methadone maintenance therapy. All participants completed the Barratt impulsivity scale (BIS-11 before and immediately after the end of intervention and follow up. Also, Morphine and stimulating drugs in urine were analyzed. Results: The results showed that total impulsivity scores was decreased in post-test but not in follow up. That is, impulsivity decreased in both experimental groups. Results also showed that relapse rate was not significantly differed. Conclusion: The combination of Fluoxetine with Methadone maintenance therapy and impulse control group therapy, was the most effective treatment on reduction of impulsivity, but not on relapse rate, in heroin crack abusers, in the short term.

  3. Augmented reality application utility for aviation maintenance work instruction

    Science.gov (United States)

    Pourcho, John Bryan

    Current aviation maintenance work instructions do not display information effectively enough to prevent costly errors and safety concerns. Aircraft are complex assemblies of highly interrelated components that confound troubleshooting and can make the maintenance procedure difficult (Drury & Gramopadhye, 2001). The sophisticated nature of aircraft maintenance necessitates a revolutionized training intervention for aviation maintenance technicians (United States General Accounting Office, 2003). Quite simply, the paper based job task cards fall short of offering rapid access to technical data and the system or component visualization necessary for working on complex integrated aircraft systems. Possible solutions to this problem include upgraded standards for paper based task cards and the use of integrated 3D product definition used on various mobile platforms (Ropp, Thomas, Lee, Broyles, Lewin, Andreychek, & Nicol, 2013). Previous studies have shown that incorporation of 3D graphics in work instructions allow the user to more efficiently and accurately interpret maintenance information (Jackson & Batstone, 2008). For aircraft maintenance workers, the use of mobile 3D model-based task cards could make current paper task card standards obsolete with their ability to deliver relevant, synchronized information to and from the hangar. Unlike previous versions of 3D model-based definition task cards and paper task cards, which are currently used in the maintenance industry, 3D model based definition task cards have the potential to be more mobile and accessible. Utilizing augmented reality applications on mobile devices to seamlessly deliver 3D product definition on mobile devices could increase the efficiency, accuracy, and reduce the mental workload for technicians when performing maintenance tasks (Macchiarella, 2004). This proposal will serve as a literary review of the aviation maintenance industry, the spatial ability of maintenance technicians, and benefits of

  4. 14 CFR 43.12 - Maintenance records: Falsification, reproduction, or alteration.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maintenance records: Falsification, reproduction, or alteration. 43.12 Section 43.12 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE, REBUILDING, AND ALTERATION §...

  5. Propulsion controlled aircraft computer

    Science.gov (United States)

    Cogan, Bruce R. (Inventor)

    2010-01-01

    A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

  6. 50 CFR 80.17 - Maintenance.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Maintenance. 80.17 Section 80.17 Wildlife... WILDLIFE RESTORATION AND DINGELL-JOHNSON SPORT FISH RESTORATION ACTS § 80.17 Maintenance. The State is responsible for maintenance of all capital improvements acquired or constructed with Wildlife and Sport...

  7. A passive heat maintenance strategy implemented during a simulated half-time improves lower body power output and repeated sprint ability in professional Rugby Union players.

    Directory of Open Access Journals (Sweden)

    Mark Russell

    Full Text Available Reduced physical performance has been observed following the half-time period in team sports players, likely due to a decrease in muscle temperature during this period. We examined the effects of a passive heat maintenance strategy employed between successive exercise bouts on core temperature (Tcore and subsequent exercise performance. Eighteen professional Rugby Union players completed this randomised and counter-balanced study. After a standardised warm-up (WU and 15 min of rest, players completed a repeated sprint test (RSSA 1 and countermovement jumps (CMJ. Thereafter, in normal training attire (Control or a survival jacket (Passive, players rested for a further 15 min (simulating a typical half-time before performing a second RSSA (RSSA 2 and CMJ's. Measurements of Tcore were taken at baseline, post-WU, pre-RSSA 1, post-RSSA 1 and pre-RSSA 2. Peak power output (PPO and repeated sprint ability was assessed before and after the simulated half-time. Similar Tcore responses were observed between conditions at baseline (Control: 37.06±0.05°C; Passive: 37.03±0.05°C and for all other Tcore measurements taken before half-time. After the simulated half-time, the decline in Tcore was lower (-0.74±0.08% vs. -1.54±0.06%, p<0.001 and PPO was higher (5610±105 W vs. 5440±105 W, p<0.001 in the Passive versus Control condition. The decline in PPO over half-time was related to the decline in Tcore (r = 0.632, p = 0.005. In RSSA 2, best, mean and total sprint times were 1.39±0.17% (p<0.001, 0.55±0.06% (p<0.001 and 0.55±0.06% (p<0.001 faster for Passive versus Control. Passive heat maintenance reduced declines in Tcore that were observed during a simulated half-time period and improved subsequent PPO and repeated sprint ability in professional Rugby Union players.

  8. IMPROVED AERODYNAMIC APPROXIMATION MODEL WITH CASE-BASED REASONING TECHNIQUE FOR MDO OF AIRCRAFT%多学科优化中基于实例推理的气动近似模型

    Institute of Scientific and Technical Information of China (English)

    白振东; 刘虎; 柴雪; 武哲

    2008-01-01

    为提高飞机多学科优化效率,对气动近似计算模型进行了改进.在比值修正模型所构造的气动近似模型的基础上,引入了基于实例的推理技术对其加以改进.通过采用与飞机气动特性相关的参数作为实例属性,建立了飞机方案实例,并改进了实例检索公式,最后通过复用与当前方案最相似实例的修正因子改进了优化中的气动近似模型.以常规布局民用飞机概念设计为例,采用改进的气动近似模型进行了多学科优化研究.结果表明,对于具有大量设计变量的飞机方案优化问题,采用改进的气动近似模型能够有效提高计算精度与优化效率.%To increase the efficiency of the muhidisciplinary optimization of aircraft,an aerodynamic approximation model is improved.Based on the study of aerodynamic approximation model constructed by the scaling correction model,case-based reasoning technique is introduced to improve the approximation model for optimization.The aircraft case model is constructed by utilizing the plane parameters related to aerodynamic characteristics as attributes of cases,and the formula of case retrieving is improved.Finally,the aerodynamic approximation model for optimization is improved by reusing the correction factors of the most similar aircraft to the current one.The muhidisciplinary optimization of a civil aircraft concept is carried out with the improved aerodynamic approximation model.The results demonstrate that the precision and the efficiency of the optimization can be improved by utilizing the improved aerodynamic approximation model with case-based reasoning technique.

  9. The Application and Development of Non-destructive Testing in Aircraft Engine Maintenance%无损检测在航空发动机维修中的应用和发展

    Institute of Scientific and Technical Information of China (English)

    郑丽; 罗泽明; 张波

    2014-01-01

    从无损检测的定义和分类出发,介绍了在航空发动机的维修中,广泛采用的四种无损检测方法---孔探仪检测、涡流检测、超声波检测、轴承原位检测的应用情况,总结了无损检测的四个发展趋势,对工程人员和维修人员具有一定的参考价值。%Based on the definition and classify of non-destructive testing , the paper describes four widely-used non-destructive testing methods --- borescope testing, eddy current testing, ultrasonic testing and bearing in-situ testing , then summarizes the research trends of non-destructive testing from four ways . The results have some reference values to engineer and maintenance personnel.

  10. Unmanned aircraft systems

    Science.gov (United States)

    Unmanned platforms have become increasingly more common in recent years for acquiring remotely sensed data. These aircraft are referred to as Unmanned Airborne Vehicles (UAV), Remotely Piloted Aircraft (RPA), Remotely Piloted Vehicles (RPV), or Unmanned Aircraft Systems (UAS), the official term used...

  11. Military Airlift: C-17 Aircraft Program

    Science.gov (United States)

    2007-11-02

    out such a mission led Congress to ask DOD to conduct a study of the entire long- For more information on MRS-05, see CRS Report RS20915 . 22 Jonathan...many should be retired. Rising maintenance costs have led some to argue that more C-5s should be retired sooner, and the savings be applied to...34lighter-than-air" aircraft . Also known as airships, blimps, dirigibles, or zeppelins , these potentially large, helium-filled balloons offer many

  12. Planning for recall of maintenance manpower

    OpenAIRE

    Poh, Yang Siang Kelvin

    2015-01-01

    Approved for public release; distribution is unlimited Mission availability is a key component of system effectiveness wherein manpower forms a critical part of the resource requirements. Within the United States Air Force, military technicians supplement essential maintenance and logistics support for fighter aircraft. Under certain conditions, the placement of these technicians in their roles as reserve personnel creates disproportionate economic loss for the parent unit and the reserve ...

  13. Human Factors in Aviation Maintenance. Phase 1

    Science.gov (United States)

    1991-11-01

    communication in the aircraft logs , pi- during the visit? lots would sometimes verbally describe the per- formance of the plane to a lead mechanic’ or...however, handwritten input may eventually be usefl for implemeinting technology in aviation maintenance and spcf Ic maneac’ ctiiis. other applications...functions. When the auto is referred for service of a int ermittent or other problem, the data recorder may be hooked up by modem to enable e data log to

  14. Contemporary methods for realization and estimation of efficiency of 3Daudio technology application for sound interface improvement of an aircraft cabin

    Directory of Open Access Journals (Sweden)

    O. N. Korsun

    2014-01-01

    Full Text Available High information load of crew is one of the main problems of modern piloted aircraft therefore researches on approving data representation form, especially in critical situations are a challenge. The article considers one of opportunities to improve the interface of a modern pilot's cabin i.e. to use a spatial sound (3D - audio technology. The 3D - audio is a technology, which recreates a spatially directed sound in earphones or via loudspeakers. Spatial audio-helps, which together with information on danger will specify also the direction from which it proceeds, can reduce time of response to an event and, therefore, increase situational safety of flight. It is supposed that helps will be provided through pilot's headset therefore technology realization via earphones is discussed.Now the main hypothesis explaining the human ability to recognize the position of a sound source in space, asserts that the human estimates distortion of a sound signal spectrum at interaction with the head and an auricle depending on an arrangement of the sound source. For exact describing the signal spectrum variations there are such concepts as Head Related Impulse Response (HRIR and Head Related Transfer Function (HRTF. HRIR is measured in humans or dummies. At present the most full-scale public HRIR library is CIPIC HRTF Database of CIPIC Interface Laboratory at UC Davis.To have 3D audio effect, it is necessary to simulate a mono-signal conversion through the linear digital filters with anthropodependent pulse characteristics (HRIR for the left and right ear, which correspond to the chosen direction. Results should be united in a stereo file and applied for reproduction to the earphones.This scheme was realized in Matlab, and the received software was used for experiments to estimate the quantitative characteristics of technology. For processing and subsequent experiments the following sound signals were chosen: a fragment of the classical music piece "Polovetsky

  15. Maintenance Business Plans.

    Science.gov (United States)

    Adams, Matt

    2002-01-01

    Discusses maintenance business plans, statements which provide accountability for facilities maintenance organizations' considerable budgets. Discusses the plan's components: statement of plan objectives, macro and detailed description of the facility assets, maintenance function descriptions, description of key performance indicators, milestone…

  16. To the efficiency assessment of the maintenace of aircraft onboard systems

    Directory of Open Access Journals (Sweden)

    N. V. Сhekrizhev

    2015-01-01

    Full Text Available This article considers efficiency assessment of the maintenance of onboard systems of aircraft based on suggested «ideal» model with a set of parameters, criteria and evaluation function.

  17. THE FORMATION OF MINIMUM LISTS OF AIRCRAFT EQUIPMENT PROVIDING SAFE AND REGULAR FLIGHTS

    Directory of Open Access Journals (Sweden)

    Y. M. Chinyuchin

    2014-01-01

    Full Text Available In this article the key aspects for ensuring safe, regular and economically feasible aircraft operation and maintenance are considered with reliance to scientifically proven admissible failure minimum equipment lists.

  18. Review of factors affecting aircraft wet runway performance

    Science.gov (United States)

    Yager, T. J.

    1983-01-01

    Problems associated with aircraft operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research results from investigations conducted at the Langley Aircraft Landing Loads and Traction Facility and from tests with instrumented ground vehicles and aircraft are summarized to indicate the effects of different aircraft, tire, and runway parameters. Several promising means are described for improving tire/runway water drainage capability, brake system efficiency, and pilot training to help optimize aircraft traction performance on wet runways.

  19. Federal Aviation Administration (FAA airworthiness certification for ceramic matrix composite components in civil aircraft systems

    Directory of Open Access Journals (Sweden)

    Gonczy Stephen T.

    2015-01-01

    Full Text Available Ceramic matrix composites (CMCs are being designed and developed for engine and exhaust components in commercial aviation, because they offer higher temperature capabilities, weight savings, and improved durability compared to metals. The United States Federal Aviation Administration (FAA issues and enforces regulations and minimum standards covering the safe manufacture, operation, and maintenance of civil aircraft. As new materials, these ceramic composite components will have to meet the certification regulations of the FAA for “airworthiness”. The FAA certification process is defined in the Federal Aviation Regulations (Title 14 of the Code of Federal Regulations, FAA policy statements, orders, advisory circulars, technical standard orders, and FAA airworthiness directives. These regulations and documents provide the fundamental requirements and guidelines for design, testing, manufacture, quality assurance, registration, operation, inspection, maintenance, and repair of aircraft systems and parts. For metallic parts in aircraft, the FAA certification and compliance process is well-established for type and airworthiness certification, using ASTM and SAE standards, the MMPDS data handbook, and FAA advisory circulars. In a similar manner for polymer matrix composites (PMC, the PMC industry and the FAA have jointly developed and are refining parallel guidelines for polymer matrix composites (PMCs, using guidance in FAA circulars and the CMH-17 PMC handbook. These documents discuss design methods and codes, material testing, property data development, life/durability assessment, production processes, QA procedures, inspection methods, operational limits, and repairs for PMCs. For ceramic composites, the FAA and the CMC and aerospace community are working together (primarily through the CMH-17 CMC handbook to define and codify key design, production, and regulatory issues that have to be addressed in the certification of CMC components in

  20. Aircraft Attitude Control by Fuzzy Control

    Science.gov (United States)

    Kato, Akio; Matsuba, Takashi

    The fuzzy control law to improve dutch roll characteristics of aircraft was designed and its control performance was evaluated. First, the control law was designed for a small-high speed aircraft at low altitude and low-speed flight conditions. The control law was then applied to flight conditions from minimum speed to supersonic speed and from sea level to high altitude. The control performance for these conditions was evaluated. Furthermore, this control law was adapted to a large transport aircraft with no parameter changes. The evaluation showed good control performance to improve the dutch roll characteristics under all flight conditions for both small high-speed aircraft and large transport aircraft without the parameter changes. This means that the fuzzy control proved to provide effective flexible application to aircraft stability augmentation. If an aircraft in actual flight is in strong air turbulence, inputs to the fuzzy controller may exceed the limit of its effective range. To cope with this problem, the countermeasures were introduced, their methods tested, and their effectiveness proved.

  1. 中频感应加热处理在提高航空钢丝绳疲劳性能中的运用%Application of medium frequency induction heating treatment to improve aircraft wire rope fatigue performance

    Institute of Scientific and Technical Information of China (English)

    马明刚; 唐章国; 吴炳章

    2013-01-01

    为提高航空钢丝绳的疲劳寿命,应消除钢丝绳生产中产生的捻制应力.现有消除应力的方法主要有机械矫直、旋转矫直、油回火处理,但均不能有效消除钢丝绳的内应力.将金属回复理论运用于航空用钢丝绳的研发中,成功开发出用于航空钢丝绳消除应力的专用中频感应加热处理设备,采用此设备对6×19+ IWS-5.1航空钢丝绳进行研制.经过160℃,收线速度25 m/min中频感应加热处理后,钢丝绳无松散、无起壳现象,平直度较好,通条力学性能稳定,疲劳次数达16万次,破断拉力在22.3 kN以上,远高于YB/T 5197-2005《航空用钢丝绳》中相应指标的要求.%In order to improve the fatigue life of aircraft wire rope,the twist stress generated in wire rope production should be eliminated.The current methods to eliminate stress are mainly mechanical straightening,rotation straightening,oil-tempered treatment,but all can' t eliminate inner stress in rope effectively.Apply metal restore theory to aircraft wire rope development,the special medium frequency induction heating equipment for eliminating aircraft wire rope stress was developed successfully.Adopting the equipment to develop 6 × 19 + IWS-5.1 aircraft wire rope,after medium frequency induction heating at 160 ℃ and 25 m/min speed,the wire rope has no loose,no flake,straightness is better,constant quality,fatigue number is up to 160 thousand times,break force is above 22.3 kN,far more super to the requirement of corresponding index of YB/T 5197-2005 aircraft wire rope.

  2. VT Maintenance District Boundaries

    Data.gov (United States)

    Vermont Center for Geographic Information — Vermont has eight transportation maintenance districts which are responsible for all maintenance activities on state highways, and for providing technical assistance...

  3. Development and experimental characterization of a fuel cell powered aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, Thomas H.; Moffitt, Blake A.; Mavris, Dimitri N.; Parekh, David E. [Georgia Institute of Technology, Atlanta, GA 30332-0405 (United States)

    2007-09-27

    This paper describes the characteristics and performance of a fuel cell powered unmanned aircraft. The aircraft is novel as it is the largest compressed hydrogen fuel cell powered airplane built to date and is currently the only fuel cell aircraft whose design and test results are in the public domain. The aircraft features a 500 W polymer electrolyte membrane fuel cell with full balance of plant and compressed hydrogen storage incorporated into a custom airframe. Details regarding the design requirements, implementation and control of the aircraft are presented for each major aircraft system. The performances of the aircraft and powerplant are analyzed using data from flights and laboratory tests. The efficiency and component power consumption of the fuel cell propulsion system are measured at a variety of flight conditions. The performance of the aircraft powerplant is compared to other 0.5-1 kW-scale fuel cell powerplants in the literature and means of performance improvement for this aircraft are proposed. This work represents one of the first studies of fuel cell powered aircraft to result in a demonstration aircraft. As such, the results of this study are of practical interest to fuel cell powerplant and aircraft designers. (author)

  4. Commercial aircraft composite technology

    CERN Document Server

    Breuer, Ulf Paul

    2016-01-01

    This book is based on lectures held at the faculty of mechanical engineering at the Technical University of Kaiserslautern. The focus is on the central theme of societies overall aircraft requirements to specific material requirements and highlights the most important advantages and challenges of carbon fiber reinforced plastics (CFRP) compared to conventional materials. As it is fundamental to decide on the right material at the right place early on the main activities and milestones of the development and certification process and the systematic of defining clear requirements are discussed. The process of material qualification - verifying material requirements is explained in detail. All state-of-the-art composite manufacturing technologies are described, including changes and complemented by examples, and their improvement potential for future applications is discussed. Tangible case studies of high lift and wing structures emphasize the specific advantages and challenges of composite technology. Finally,...

  5. Aircraft emission research within ISTC project

    Energy Technology Data Exchange (ETDEWEB)

    Dedesh, V.; Leut, A.; Boris, S. [Scientific Research Center at the Gromov Flight, Research Institute (Russian Federation)

    2001-08-01

    This research is aimed at obtaining experimental data on contamination of the atmosphere by emissions from aircraft engines in cruise flight conditions, to establish and improve models of the physical and chemical processes which take place in the aircraft wake and in the general zone of air traffic corridors. An Su-24 'sounder' aircraft equipped with an air sampling and collection system has been established to obtain the necessary atmospheric samples in flight, and procedures have been developed for performing the research flights. Techniques have also been developed for chemical analysis of the samples. (authors)

  6. Multidisciplinary Techniques and Novel Aircraft Control Systems

    Science.gov (United States)

    Padula, Sharon L.; Rogers, James L.; Raney, David L.

    2000-01-01

    The Aircraft Morphing Program at NASA Langley Research Center explores opportunities to improve airframe designs with smart technologies. Two elements of this basic research program are multidisciplinary design optimization (MDO) and advanced flow control. This paper describes examples where MDO techniques such as sensitivity analysis, automatic differentiation, and genetic algorithms contribute to the design of novel control systems. In the test case, the design and use of distributed shape-change devices to provide low-rate maneuvering capability for a tailless aircraft is considered. The ability of MDO to add value to control system development is illustrated using results from several years of research funded by the Aircraft Morphing Program.

  7. Joint Path Planning for Warship and Aircraft Based on Improved Weighted A* Algorithm%基于改进加权A∗算法的舰机联合航迹规划

    Institute of Scientific and Technical Information of China (English)

    王玮; 王玉惠; 王文敬; 张洪波

    2016-01-01

    The path planning for warship-aircraft joint operation is studied. Firstly, the weapon system of the destroyer is analyzed to obtain the safe distance when the shipboard helicopter and the destroyer are performing a task cooperatively. Since the traditional A∗ algorithm cannot be applied directly to the path planning for warship-aircraft joint operation, the security costs and the path safety factor are introduced. An improved weighted A∗ algorithm is given based on the traditional algorithm, to solve the path planning problem for warship-aircraft joint operation. Finally, a case simulation is given to verify the effectiveness of the improved algorithm.%基于改进加权A∗算法研究了舰机联合航迹规划问题。首先,通过分析驱逐舰的武器系统结构,得出驱逐舰和舰载直升机在联合执行任务时的安全距离;由于传统A∗算法运用于舰机联合航迹规划问题的局限性,引入安全代价和路径安全值加权系数,基于传统A∗算法给出了改进加权A∗算法,协同规划舰艇和舰载机的路径;最后,通过案例仿真验证了算法的有效性。

  8. Aviation Equipment Maintenance Safety Assessment Based on Improved Support Vector Machine%基于改进支持向量机的航空装备维修安全评估

    Institute of Scientific and Technical Information of China (English)

    柳月青; 徐吉辉

    2016-01-01

    The traditional assessment of aviation equipment maintenance safety uses the method of qualitative assessment. Because of subjectivity,strong arbitrariness,and lack of operability in the traditional assessment,the improved Support Vector Machine (SVM) based on kernel density estimation is proposed. The evaluation index system of aviation equipment maintenance safety is constructed,and the comprehensive assessment on aviation equipment maintenance situation of a certain unit is conducted by improved Support Vector Machine (SVM),on the basis of using Analytic Hierarchy Process (AHP) to calculate its weight,which provides a scientific method for aviation equipment maintenance safety assessment,and has a strong theoretical and practical significance to ensure the security of aviation equipment maintenance.%传统航空装备维修安全评估大多采用定性评估方法,针对传统评估中存在主观性、随意性过强,实践中缺乏可操作性等问题,提出了基于核密度估计的改进支持向量机。构建了航空装备维修安全评估指标体系,在利用层次分析法对其权重进行计算的基础上,通过改进支持向量机对某单位航空装备维修状况进行了全面评估,为航空装备维修安全评估提供了科学的方法,对确保航空装备维修安全具有较强的理论和现实意义。

  9. Comprehensive evaluation model of power information operation and maintenance skills based on improved radar chart method%基于改进雷达图法的电力信息运维技能综合评价模型

    Institute of Scientific and Technical Information of China (English)

    曲朝阳; 徐鹏飞; 娄建楼; 颜佳; 独健鸿; 刘芳形

    2016-01-01

    针对电力信息运维技能评价结果不够形象直观的问题,提出了基于改进雷达图法的电力信息运维技能综合评价模型。该模型的评价过程如下:首先建立电力信息运维技能评价指标体系,然后基于主客观组合赋权法确定每个子系统的综合权重,最后使用改进雷达图法构建综合评价模型对电力信息运维技能进行评价。经实例验证,该模型能够形象直观地评价电力信息运维技能,其计算速度快,可靠性高,具有实际意义。%As for the problem that the evaluation result of power information operation and maintenance skills is not figurative and visual, a comprehensive evaluation model of power information operation and maintenance skills based on improved radar chart method is proposed. The evaluation process of the model is as follows:firstly, a in⁃dex system of evaluation for power information operation and maintenance skills is established, then the overall weight of each subsystem is determined based on the subjective and objective combination weighting method, and lastly a comprehensive evaluation model is built using improved radar chart method to evaluate the power informa⁃tion operation and maintenance skills. The model can evaluate figuratively and visually power information operation and maintenance skills, and it is of fast computing speed, high reliability, and with practical significance.

  10. The effects of Crew Resource Mangement (CRM) training in airline maintenance: Results following three years' experience

    Science.gov (United States)

    Taylor, J. C.; Robertson, M. M.

    1995-01-01

    This report describes three years' evaluation of the effects of one airline's Crew Resources Management (CRM) training operation for maintenance. This evaluation focuses on the post-training attitudes of maintenance managers' and technical support professionals, their reported behaviors, and the safety, efficiency and dependable maintenance performance of their units. The results reveal a strong positive effect of the training. The overall program represents the use of CRM training as a long-term commitment to improving performance through effective communication at all levels in airline maintenance operations. The initial findings described in our previous progress reports are reinforced and elaborated here. The current results benefit from the entire pre-post training survey, which now represents total attendance of all managers and staff professionals. Additionally there are now full results from the two-month, six-month, and 12-month follow-up questionnaires, together with as many as 33 months of post-training performance data, using several indicators. In this present report, we examine participants' attitudes, their reported behaviors following the training, the performance of their work units, and the relationships among these variables. Attitudes include those measured immediately before and after the training as well as participants' attitudes months after their training. Performance includes measures, by work units, of on-time flight departures, on-schedule maintenance releases, occupational and aircraft safety, and efficient labor costs. We report changes in these performance measures following training, as well their relationships with the training participants' attitudes. Highlights of results from this training program include increased safety and improved costs associated with positive attitudes about the use of more assertive communication, and the improved management of stress. Improved on-time performance is also related to those improved

  11. 75 FR 81417 - Airworthiness Directives; Piper Aircraft, Inc. Model PA-28-161 Airplanes

    Science.gov (United States)

    2010-12-28

    ...-057-AD; Amendment 39-16543; AD 2010-26-04] RIN 2120-AA64 Airworthiness Directives; Piper Aircraft, Inc...): 2010-26-04 Piper Aircraft, Inc: Amendment 39-16543; Docket No. FAA- 2010-1006; Directorate Identifier... alternative GmbH Supplement replacement times may be Airplane approved for this part. Maintenance Manual...

  12. FAA-NASA Sixth International Conference on the Continued Airworthiness of Aircraft Structures

    Science.gov (United States)

    1995-12-01

    British Airways Human Factors in Aviation Maintenance: Current FAA Research .............................. 91 William T. Shepherd, Federal Aviation...Development of Advanced Structural Analysis Methodologies for Predicting W idespread Fatigue Damage in Aircraft Structures...where satellite communications to transmit aircraft position data derived from GPS directly to controllers via data link. On June 21, FAA and Qantas

  13. Effectiveness of Condition-Based Maintenance in Army Aviation

    Science.gov (United States)

    2009-06-12

    quickly moved ahead with applying these new technologies to maintenance programs. Aviation maintainers started utilizing magnetic flux, ultrasound ...was mission abort rate. A mission abort occurs when an operational aircraft assigned to perform a mission, becomes unable to perform its assigned...a failure occur during mission execution. A study from AMRDEC in January 2009 referenced the mean time between maintenance abort for a handful of

  14. Metabolic Syndrome and Cardio-Cerebrovascular Risk Disparities Between Pilots and Aircraft Mechanics.

    Science.gov (United States)

    Kim, Myeong-Bo; Kim, Hyun-Jin; Kim, Soo-Hyeon; Lee, Suk-Ho; Lee, Se-Ho; Park, Won-Ju

    2017-09-01

    In the Republic of Korea Air Force, the health of pilots is strictly supervised, but there is comparatively not enough interest in aircraft mechanics' health. Among mechanics, who are heavily involved in military aircraft maintenance, the occurrence of sudden cardio-cerebrovascular diseases (CCVDs) is a possible risk factor during the maintenance process, which should be performed perfectly. We performed health examinations on 2123 male aircraft pilots and 1271 aircraft mechanics over 30 yr of age and determined the prevalence of metabolic syndrome (MetS), an important risk factor for CCVDs. The prevalence of MetS in the aircraft mechanics (21.3%) was significantly higher than in the pilots (12.6%), and the gap in prevalence tended to grow as age increased. Among aircraft mechanics in their 30s and 40s, the prevalence of MetS was lower than in the general population. However, the prevalence of MetS among aircraft mechanics in their 50s (36.0%) was similar to that in the general population (35.7%). Systematic health management is needed for aircraft mechanics for aviation safety and for the maintenance of military strength via the prevention of CCVDs.Kim M-B, Kim H-J, Kim S-H, Lee S-H, Lee S-H, Park W-J. Metabolic syndrome and cardio-cerebrovascular risk disparities between pilots and aircraft mechanics. Aerosp Med Hum Perform. 2017; 88(9):866-870.

  15. A Situational Maintenance Model

    DEFF Research Database (Denmark)

    Luxhoj, James T.; Thorsteinsson, Uffe; Riis, Jens Ove

    1997-01-01

    An overview of trend in maintenance management and presentation of a situational model and an analytical tools for identification of managerial efforts in maintenance.......An overview of trend in maintenance management and presentation of a situational model and an analytical tools for identification of managerial efforts in maintenance....

  16. A Situational Maintenance Model

    DEFF Research Database (Denmark)

    Luxhoj, James T.; Thorsteinsson, Uffe; Riis, Jens Ove

    1997-01-01

    An overview of trend in maintenance management and presentation of a situational model and an analytical tools for identification of managerial efforts in maintenance.......An overview of trend in maintenance management and presentation of a situational model and an analytical tools for identification of managerial efforts in maintenance....

  17. Aircraft Noise Prediction

    OpenAIRE

    2014-01-01

    This contribution addresses the state-of-the-art in the field of aircraft noise prediction, simulation and minimisation. The point of view taken in this context is that of comprehensive models that couple the various aircraft systems with the acoustic sources, the propagation and the flight trajectories. After an exhaustive review of the present predictive technologies in the relevant fields (airframe, propulsion, propagation, aircraft operations, trajectory optimisation), the paper add...

  18. Lean thinking for a maintenance process

    Directory of Open Access Journals (Sweden)

    Sherif Mostafa

    2015-01-01

    Full Text Available The maintenance process shares significant operating costs in an organisation. Lean thinking can be incorporated into maintenance activities through applying its principles and practices/tools. Lean maintenance (LM is a prerequisite for lean manufacturing systems. This research proposes a new structure for LM process based on a systematic literature review of a significant number of related articles that were published on LM. The process structure is designed based on the five lean principles to guide and support organisations to pursue maintenance excellence. This study establishes a scheme for LM tools that are structured into 2 level 4 bundles and 26 lean practices/tools and develops a House of Waste (HoW to demonstrate the association between maintenance wastes and the LM tools. With a successful accomplishment of the proposed scheme, the performance of a maintenance department can create more improvement opportunities over time to reach the maintenance excellence status.

  19. Flight control electronics reliability/maintenance study

    Science.gov (United States)

    Dade, W. W.; Edwards, R. H.; Katt, G. T.; Mcclellan, K. L.; Shomber, H. A.

    1977-01-01

    Collection and analysis of data are reported that concern the reliability and maintenance experience of flight control system electronics currently in use on passenger carrying jet aircraft. Two airlines B-747 airplane fleets were analyzed to assess the component reliability, system functional reliability, and achieved availability of the CAT II configuration flight control system. Also assessed were the costs generated by this system in the categories of spare equipment, schedule irregularity, and line and shop maintenance. The results indicate that although there is a marked difference in the geographic location and route pattern between the airlines studied, there is a close similarity in the reliability and the maintenance costs associated with the flight control electronics.

  20. Maintenance and Condition-Based Maintenance

    Institute of Scientific and Technical Information of China (English)

    DING Jin-hua; WANG Xue-Jun; ZHOU Rong; LIN Min; Olsson Erland

    2005-01-01

    The evolution of maintenance management is briefly introduced in this paper, from corrective maintenance to preventive maintenance. First, a range of condition monitoring and fault diagnosis techniques developed in different industries are surveyed; Second, many methods of condition monitoring are presented; Third, mathematical methods used in condition monitoring are given; Then the merits and shortcomings are discussed.Efficient maintenance policies are of fundamental importance in system engineering because of their fallbacks into the safety and economics of plant operation. Applying condition-based maintenance to a system can reduce the cost and extend the availability of facilities. With the advent of personal computers as fast and cost effective machines for data acquisition and processing of multiple signals some shortcomings mentioned in condition monitoring could be solved or reduced to some extent. These PCs can be a solution as a condition monitoring based maintenance system.

  1. Mejoras al programa de mantenimiento de máquinas deslodadoras para la extracción de aceite de palma // Improving the maintenance program of extracting fruit palm oil machines

    Directory of Open Access Journals (Sweden)

    Jesús Cabrera - Gómez

    2010-09-01

    Full Text Available ResumenLa aplicación de nuevos enfoques de mantenimiento a partir de la identificación de oportunidades demejora de la confiabilidad operacional y los elementos que la componen, es una necesidad paratodas las organizaciones que pretendan incrementar sus indicadores de eficiencia. Las máquinasque son objeto de estudio en el presente trabajo, pertenecen a una importante empresa cuyo objetoes la extracción de aceite a partir de los frutos de la palma africana. Estas máquinas son atendidas,en teoría, a partir de un programa de mantenimiento preventivo que ha demostrado limitaciones, todavez que la mayor parte de las intervenciones realizadas en los últimos años muestran un caráctereminentemente reactivo. A partir de la realización de un análisis en el que fueron establecidas lasfunciones, los fallos funcionales, los modos de fallo y sus efectos, se identificaron los requerimientosde mantenimiento de estas máquinas y las tareas necesarias para asegurar la continuidad de lasfunciones, las que se cocentraron en una propuesta de programa con marcada tendencia a lasactividades proactivas.Palabras claves: mantenimiento de equipos rotatorios, confiabilidad operacional, mantenimiento__________________________________________________________________________AbstractThe application of new maintenance approaches related with operational reliability improvement andits elements is a necessity for all enterprises that intend to increase efficiency indicators. The rotatingmachines studied in this paper belong to an important plant that extracts oil from African palm treefruits. These machines are submitted, in theory, to a preventive maintenance program, but actuallythe most of maintenance activities are reactive. An analysis in order to identify functions, functionalfailures, failure modes and failure effects was made. Maintenance tasks for assuring the continuity offunctions were also identified and concentred in a proposal with a very proactive

  2. Improved Target Segmentation Algorithm for Aircraft Parking at Airport%改进的机场停泊飞行器目标分割算法

    Institute of Scientific and Technical Information of China (English)

    陆钰; 王金根; 陈秀娟; 徐靖涛

    2009-01-01

    考虑到飞行器目标在整幅图像中所占的比例往往较小,且图像背景复杂,本文提出了一种基于机场区域提取的飞行器目标分割算法.该算法首先利用Hough变换检测直线的特性,定位机场跑道和停机坪的位置,并结合教学形态学等图像处理技术去除了非机场区域;在提取机场区域后,再选择适当的阈值对图像进行分割,最后经过形态学去噪、小区域去除等步骤分割出飞行器目标.实验结果表明,该算法改进了以往机场区域提取算法保留候机楼等附属部分以及提取结果中存在机场区域以外区域的缺点,较好地实现了机场停泊飞行器目标的分割,为下一步准确识别飞行器类型奠定了基础.%Considering that the aircraft targets have less scale on the whole image with a complicated background,an algorithm is proposed to segment aircraft targets based on the airport area extracting.Firstly,by using the features of the detecting lines of the Hough transform,the runway and the apron are located.Then,the area out of the airport are wiped off by using some image processing technologies,such as mathematical morphology.After extracting the airport area,a proper threshold value is selected to segment the image.Finally,the aircraft targets are segmented after some steps,such as morphological de-noising and small area removing.The experimental result shows that the algorithm can overcome the disadvantages of the previous algorithms of the airport extraction for retaining the subsidiary parts,such as terminal buildings,thus the extracting results contain area out of the airport area.

  3. A methodology for hard/soft information fusion in the condition monitoring of aircraft

    Science.gov (United States)

    Bernardo, Joseph T.

    2013-05-01

    Condition-based maintenance (CBM) refers to the philosophy of performing maintenance when the need arises, based upon indicators of deterioration in the condition of the machinery. Traditionally, CBM involves equipping machinery with electronic sensors that continuously monitor components and collect data for analysis. The addition of the multisensory capability of human cognitive functions (i.e., sensemaking, problem detection, planning, adaptation, coordination, naturalistic decision making) to traditional CBM may create a fuller picture of machinery condition. Cognitive systems engineering techniques provide an opportunity to utilize a dynamic resource—people acting as soft sensors. The literature is extensive on techniques to fuse data from electronic sensors, but little work exists on fusing data from humans with that from electronic sensors (i.e., hard/soft fusion). The purpose of my research is to explore, observe, investigate, analyze, and evaluate the fusion of pilot and maintainer knowledge, experiences, and sensory perceptions with digital maintenance resources. Hard/soft information fusion has the potential to increase problem detection capability, improve flight safety, and increase mission readiness. This proposed project consists the creation of a methodology that is based upon the Living Laboratories framework, a research methodology that is built upon cognitive engineering principles1. This study performs a critical assessment of concept, which will support development of activities to demonstrate hard/soft information fusion in operationally relevant scenarios of aircraft maintenance. It consists of fieldwork, knowledge elicitation to inform a simulation and a prototype.

  4. 78 FR 41285 - Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

    Science.gov (United States)

    2013-07-10

    ..., Engine Controls, dated November 30, 2010, found in PILATUS PC-7 Turbo Trainer Aircraft Maintenance Manual... to the specified products. The NPRM was published in the Federal Register on April 26, 2013 (78 FR... participate in developing this AD. We received no comments on the NPRM (78 FR 24689, April 26, 2013) or on...

  5. Survival analysis of aging aircraft

    Science.gov (United States)

    Benavides, Samuel

    This study pushes systems engineering of aging aircraft beyond the boundaries of empirical and deterministic modeling by making a sharp break with the traditional laboratory-derived corrosion prediction algorithms that have shrouded real-world failures of aircraft structure. At the heart of this problem is the aeronautical industry's inability to be forthcoming in an accurate model that predicts corrosion failures in aircraft in spite of advances in corrosion algorithms or improvements in simulation and modeling. The struggle to develop accurate corrosion probabilistic models stems from a multitude of real-world interacting variables that synergistically influence corrosion in convoluted and complex ways. This dissertation, in essence, offers a statistical framework for the analysis of structural airframe corrosion failure by utilizing real-world data while considering the effects of interacting corrosion variables. This study injects realism into corrosion failures of aging aircraft systems by accomplishing four major goals related to the conceptual and methodological framework of corrosion modeling. First, this work connects corrosion modeling from the traditional, laboratory derived algorithms to corrosion failures in actual operating aircraft. This work augments physics-based modeling by examining the many confounding and interacting variables, such as environmental, geographical and operational, that impact failure of airframe structure. Examined through the lens of censored failure data from aircraft flying in a maritime environment, this study enhances the understanding between the triad of the theoretical, laboratory and real-world corrosion. Secondly, this study explores the importation and successful application of an advanced biomedical statistical tool---survival analysis---to model censored corrosion failure data. This well-grounded statistical methodology is inverted from a methodology that analyzes survival to one that examines failures. Third, this

  6. 222-S Laboratory maintenance implementation plan

    Energy Technology Data Exchange (ETDEWEB)

    Heinemann, J.L.

    1997-08-13

    This Maintenance Improvement Plan has been developed for maintenance functions associated with the 222-S Laboratory. This plan is developed from the guidelines presented by Department of Energy (DOE) Order 4330.4B, Maintenance Management Program (DOE 1994), Chapter 11. The objective of this plan is to provide information for establishing and identifying WMH conformance programs and policies applicable to implementation of DOE Order 4330.4B guidelines. In addition, this maintenance plan identifies the actions necessary to develop a cost effective and efficient maintenance program at 222-S Laboratory. Maintenance activities are mainly going to be performed by existing maintenance organizations within Waste Management Federal Services of Hanford (WMH). Most maintenance performed at 222-S Laboratory is performed by the 222-S Laboratory maintenance organization. This 222-S Laboratory Maintenance Implementation Plan provides the interface requirements and responsibilities as they apply specifically to 222-S Laboratory. This document provides an implementation schedule which has been developed for items considered to be deficient or in need of improvement. The discussion section as applied to 222-S Laboratory implementation has been developed from a review of programs and practices utilizing the graded approach. Biennial review and additional reviews are conducted as significant programmatic and mission changes are made. This document is revised as necessary to keep this document current and in compliance with DOE requirements.

  7. View of QF-106 aircraft cockpit

    Science.gov (United States)

    1997-01-01

    View of the cockpit and instrument panel of the QF-106 airplane used in the Eclipse project. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  8. Cable Tensiometer for Aircraft

    Science.gov (United States)

    Nunnelee, Mark (Inventor)

    2008-01-01

    The invention is a cable tensiometer that can be used on aircraft for real-time, in-flight cable tension measurements. The invention can be used on any aircraft cables with high precision. The invention is extremely light-weight, hangs on the cable being tested and uses a dual bending beam design with a high mill-volt output to determine tension.

  9. 14 CFR 135.441 - Transfer of maintenance records.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Transfer of maintenance records. 135.441 Section 135.441 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... REQUIREMENTS: COMMUTER AND ON DEMAND OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT...

  10. 14 CFR 135.439 - Maintenance recording requirements.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintenance recording requirements. 135.439 Section 135.439 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... REQUIREMENTS: COMMUTER AND ON DEMAND OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT...

  11. Propulsion controlled aircraft research

    Science.gov (United States)

    Fullerton, C. Gordon

    1993-01-01

    The NASA Dryden Flight Research Facility has been conducting flight, ground simulator, and analytical studies to investigate the use of thrust modulation on multi-engine aircraft for emergency flight control. Two general methods of engine only control have been studied; manual manipulation of the throttles by the pilot, and augmented control where a computer commands thrust levels in response to pilot attitude inputs and aircraft motion feedbacks. This latter method is referred to as the Propulsion Controlled Aircraft (PCA) System. A wide variety of aircraft have been investigated. Simulation studies have included the B720, F-15, B727, B747 and MD-11. A look at manual control has been done in actual flight on the F15, T-38, B747, Lear 25, T-39, MD-11 and PA-30 Aircraft. The only inflight trial of the augmented (PCA) concept has been on an F15, the results of which will be presented below.

  12. Aircraft operations management manual

    Science.gov (United States)

    1992-01-01

    The NASA aircraft operations program is a multifaceted, highly diverse entity that directly supports the agency mission in aeronautical research and development, space science and applications, space flight, astronaut readiness training, and related activities through research and development, program support, and mission management aircraft operations flights. Users of the program are interagency, inter-government, international, and the business community. This manual provides guidelines to establish policy for the management of NASA aircraft resources, aircraft operations, and related matters. This policy is an integral part of and must be followed when establishing field installation policy and procedures covering the management of NASA aircraft operations. Each operating location will develop appropriate local procedures that conform with the requirements of this handbook. This manual should be used in conjunction with other governing instructions, handbooks, and manuals.

  13. Maintenance therapy in multiple myeloma

    Directory of Open Access Journals (Sweden)

    Jean-Luc Harousseau

    2009-08-01

    Full Text Available The treatment of multiple myeloma (MM has changed dramatically in the past twenty years with the introduction of high-dose therapy plus autologous stem-cell transplantation (ASCT in younger patients and, more recently, of three novel agents (thalidomide, bortezomib, and lenalidomide. When conventional chemotherapy was the only available possibility, complete responses (CR were very rare and the objective of maintenance was to prolong remission duration by continuing the same type of treatment that induced the initial response. With recent therapeutic improvements, CR achievement becomes a realistic goal that, in most cases, is significantly correlated with the outcome (1. Therefore, both the nature and the impact of maintenance therapy have changed. Maintenance therapy is based currently on novel agents, and its objective is not only to control the clone but also to further decrease the tumor burden and improve the quality of response. A number of randomized studies show a benefit from maintenance therapy with novel agents (until now, mostly thalidomide, at least in terms of response rate and progression-free survival (PFS. However, there is still a debate as concerns the impact on overall survival (OS and the optimal administration of maintenance therapy.

  14. Innovations in Aircraft Design

    Science.gov (United States)

    1997-01-01

    The Boeing 777 carries with it basic and applied research, technology, and aerodynamic knowledge honed at several NASA field centers. Several Langley Research Center innovations instrumental to the development of the aircraft include knowledge of how to reduce engine and other noise for passengers and terminal residents, increased use of lightweight aerospace composite structures for increased fuel efficiency and range, and wind tunnel tests confirming the structural integrity of 777 wing-airframe integration. Test results from Marshall Space Flight Center aimed at improving the performance of the Space Shuttle engines led to improvements in the airplane's new, more efficient jet engines. Finally, fostered by Ames Research Center, the Boeing 777 blankets that protect areas of the plane from high temperatures and fire have a lineage to Advanced Flexible Reusable Surface Insulation used on certain areas of the Space Shuttle. According to Boeing Company estimates, the 777 has captured three-quarters of new orders for airplanes in its class since the program was launched.

  15. 进港飞机调度多目标优化问题的改进NSGA-II算法%Improved Nondominated Sorting Genetic Algorithm II for Multi-Objective Optimization of Scheduling Arrival Aircrafts

    Institute of Scientific and Technical Information of China (English)

    冯翔; 杨红雨

    2014-01-01

    基于多目标优化问题的Pareto最优解概念,提出了一种求解非劣解集的改进非支配排序遗传算法(NSGA-II),用于解决多条跑道情况下进港航班调度问题,要求航班总延误时间平方和及总延误成本两个目标最少。重点讨论了算法实现中的基于最近邻思想的启发式交叉算子和改进的变异算子,以及对非劣解集的筛选操作。最后进行了仿真实验,对优化结果进行了分析比较。研究结果表明改进NSGA-II算法对多跑道进港飞机调度多目标优化问题具有较好的应用前景。%Based on the Pareto optimal conception,an Improved nondominated sorting genetic algorithm II (NSGA-II) seeking non-inferior solution set of multi-objective optimization (MO) problems is proposed, while the heuristic crossover operator based on nearest-neighborhood, the improved mutation operator and the filtering of non-inferior solutions are focused and discussed. The algorithm proposed is applied to a two-objective optimization of scheduling of arrival aircrafts at an airport with multiple runways, where both the sum of all the delays squared and the fuel cost of all the aircrafts were required to be minimized. After the simulation experiment, the optimal solutions are analyzed and compared with the best solutions founded by some existing algorithms. The research result demonstrates that improved NSGA-II possesses a good application foreground for multi-objective optimization of scheduling arrival aircrafts at an airport with multiple runways.

  16. Reliability and optimization, application to safety of aircraft structures

    OpenAIRE

    Chu, Liu

    2016-01-01

    Tremendous struggles of researchers in the field of aerodynamic design and aircraft production were made to improve wing airfoil by optimization techniques. The development of computational fluid dynamic (CFD) in computer simulation cuts the expense of aerodynamic experiment while provides convincing results to simulate complicated situation of aircraft. In our work, we chose a special and important part of aircraft, namely, the structure of wing.Reliability based optimization is one of the m...

  17. Stress and Aircraft Maintenance Performance in a Combat Environment

    Science.gov (United States)

    1988-08-01

    CiMy State. anld ZIP Code) Department of Management and Marketing Air Force Humn Resources Laboratory Cullowhee, North Carolina 28723 Wright-Patterson...the flight line as all of the wing’s resources are now headed for the bed-down location. At the overseas base, the activity accelerates as stateside...measured by self-reports, other paper-and-pencil instruments, Rorschach tests, urinalysis (catecholamines), blood tests (cortisol, androgens), heart rate

  18. Selected Aircraft Throttle Controller With Support Of Fuzzy Expert Inference System

    Directory of Open Access Journals (Sweden)

    Żurek Józef

    2014-12-01

    Full Text Available The paper describes Zlin 143Lsi aircraft engine work parameters control support method – hourly fuel flow as a main factor under consideration. The method concerns project of aircraft throttle control support system with use of fuzzy logic (fuzzy inference. The primary purpose of the system is aircraft performance optimization, reducing flight cost at the same time and support proper aircraft engine maintenance. Matlab Software and Fuzzy Logic Toolbox were used in the project. Work of the system is presented with use of twenty test samples, five of them are presented graphically. In addition, system control surface, included in the paper, supports system all work range analysis.

  19. Research on Improving Teachers' Professional Quality of Higher Vocational Aeronautic Maintenance Major%提高高职航空维修类教师的职业素养的研究

    Institute of Scientific and Technical Information of China (English)

    谭卫娟

    2012-01-01

    The key to vigorously develop vocational education is to build a high-quality teacher team. Aeronautic maintenance major closely centers development of military aviation and civil aviation, setting up this major is to serve regional economic development, and it belongs to "industrial support". Whether can train high-end skilled personnel of aeronautic maintenance major who are able to work in less well conditions, be employed and remained and create performance lies in the way of improving professionalism of the teachers of aeronautic maintenance major.%大力发展职业教育,关键在于建设一支高质量的教师队伍.航空维修类专业,是紧紧围绕我国军用航空与民用航空发展,服务区域经济发展开办的专业,属于“产业支撑型”专业.是否能培养出“下得去、用得上、留得住、出业绩”的航空维修类高端技能型人才,前提在于如何提高航空维修类教师的职业素养.

  20. Cost savings from performance-based maintenance contracting

    NARCIS (Netherlands)

    Straub, A.

    2009-01-01

    New procurement approaches combined with performance-based building approaches should reduce costs, but empirical qualitative and quantitative studies are lacking. Performance-based maintenance contracts give maintenance suppliers incentives to improve their way of working. Innovative,

  1. Simulation based comparison of predictive maintenance policies

    NARCIS (Netherlands)

    Tinga, T.; Janssen, R.H.P.; Steenbergen, R.; Van Gelder, P.

    2013-01-01

    When an asset is operated in variable conditions, its operational efficiency can be improved significantly when the maintenance is performed in a dynamic manner. This means that variations in usage and operating environment are taken into account when deciding on the length of the maintenance interv

  2. Simulation based comparison of predictive maintenance policies

    NARCIS (Netherlands)

    Tinga, Tiedo; Janssen, R.H.P.; Steenbergen, R.; van Gelder, P.

    2013-01-01

    When an asset is operated in variable conditions, its operational efficiency can be improved significantly when the maintenance is performed in a dynamic manner. This means that variations in usage and operating environment are taken into account when deciding on the length of the maintenance

  3. Maintenance planning and organisation at Appin Colliery

    Energy Technology Data Exchange (ETDEWEB)

    Dawkins, G.; O`Brien, B. [Appin Colliery, Appin, NSW (Australia)

    1994-12-31

    At the modern Appin Colliery 2.5 million tonnes are produced per year by 390 employees from one longwall and four development units. The maintenance organisation has both mechanical and electrical departments. Recent BHP Collieries improvement initiatives have benefitted the maintenance organisation at Appin in many ways, particularly with senior management support, an effective maintenance business plan and documented programme. With accent on skills and teamwork, maintenance times, and therefore costs have been reduced. Heightened communication has led to more acute condition monitoring.

  4. Predicting Visibility of Aircraft

    Science.gov (United States)

    Watson, Andrew; Ramirez, Cesar V.; Salud, Ellen

    2009-01-01

    Visual detection of aircraft by human observers is an important element of aviation safety. To assess and ensure safety, it would be useful to be able to be able to predict the visibility, to a human observer, of an aircraft of specified size, shape, distance, and coloration. Examples include assuring safe separation among aircraft and between aircraft and unmanned vehicles, design of airport control towers, and efforts to enhance or suppress the visibility of military and rescue vehicles. We have recently developed a simple metric of pattern visibility, the Spatial Standard Observer (SSO). In this report we examine whether the SSO can predict visibility of simulated aircraft images. We constructed a set of aircraft images from three-dimensional computer graphic models, and measured the luminance contrast threshold for each image from three human observers. The data were well predicted by the SSO. Finally, we show how to use the SSO to predict visibility range for aircraft of arbitrary size, shape, distance, and coloration. PMID:19462007

  5. Rural road maintenance management

    OpenAIRE

    Johannessen, B.

    1999-01-01

    This manual summarizes relevant Cambodian government policies regarding rural road maintenance. Chapter 2 defines the various components of road maintenance and describes an effective strategy and organization which addresses the maintenance requirements of rural roads in Cambodia. Chapter 3 is a brief description of the planning, implementation and reporting cycle required in an effective road maintenance management system. Chapter 4 summarizes the contracts management procedures, and finall...

  6. Economic effects of propulsion system technology on existing and future transport aircraft

    Science.gov (United States)

    Sallee, G. P.

    1974-01-01

    The results of an airline study of the economic effects of propulsion system technology on current and future transport aircraft are presented. This report represents the results of a detailed study of propulsion system operating economics. The study has four major parts: (1) a detailed analysis of current propulsion system maintenance with respect to the material and labor costs encountered versus years in service and the design characteristics of the major elements of the propulsion system of the B707, b727, and B747. (2) an analysis of the economic impact of a future representative 1979 propulsion system is presented with emphasis on depreciation of investment, fuel costs and maintenance costs developed on the basis of the analysis of the historical trends observed. (3) recommendations concerning improved methods of forecasting the maintenance cost of future propulsion systems are presented. A detailed method based on the summation of the projected labor and material repair costs for each major engine module and its installation along with a shorter form suitable for quick, less detailed analysis are presented, and (4) recommendations concerning areas where additional technology is needed to improve the economics of future commercial propulsion systems are presented along with the suggested economic benefits available from such advanced technology efforts.

  7. Reliability centered maintenance mini-seminar

    Energy Technology Data Exchange (ETDEWEB)

    Laakso, K.; Simola, K. (eds.) [VTT Automation, Espoo (Finland)

    2000-10-01

    In the Earlier NKS-project RAK-1 (1994-1997), the sub-project RAK-1.4, 'Maintenance Strategies and Ageing' focused on development of methodologies and tools for improving maintenance strategies. In the NKS/SOS-2 project (1998-2001), the maintenance related Nordic co-operation is continued. For exchange of information and as background and for discussions related to maintenance decisions in the NKS/SOS-2 project, a mini-seminar on maintenance strategies with an emphasis on reliability centred maintenance (RCM) approaches was arranged 14.10.1999. The report summarises the topics of the presentations and discussions at the seminar. The transparencies presented at the mini-seminar are enclosed in this report. (au)

  8. Asphalt in Pavement Maintenance.

    Science.gov (United States)

    Asphalt Inst., College Park, MD.

    Maintenance methods that can be used equally well in all regions of the country have been developed for the use of asphalt in pavement maintenance. Specific information covering methods, equipment and terminology that applies to the use of asphalt in the maintenance of all types of pavement structures, including shoulders, is provided. In many…

  9. Tropospheric sampling with aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Daum, P.H.; Springston, S.R.

    1991-03-01

    Aircraft constitute a unique environment which places stringent requirements on the instruments used to measure the concentrations of atmospheric trace gases and aerosols. Some of these requirements such as minimization of size, weight, and power consumption are general; others are specific to individual techniques. This review presents the basic principles and considerations governing the deployment of trace gas and aerosol instrumentation on an aircraft. An overview of common instruments illustrates these points and provides guidelines for designing and using instruments on aircraft-based measurement programs.

  10. SOLAR AIRCRAFT DESIGN

    OpenAIRE

    RAHMATI, Sadegh; GHASED, Amir

    2015-01-01

    Abstract. Generally domain Aircraft uses conventional fuel. These fuel having limited life, high cost and pollutant. Also nowadays price of petrol and other fuels are going to be higher, because of scarcity of those fuels. So there is great demand of use of non-exhaustible unlimited source of energy like solar energy. Solar aircraft is one of the ways to utilize solar energy. Solar aircraft uses solar panel to collect the solar radiation for immediate use but it also store the remaining part ...

  11. Lightning hazards to aircraft

    Science.gov (United States)

    Corn, P. B.

    1978-01-01

    Lightning hazards and, more generally, aircraft static electricity are discussed by a representative for the Air Force Flight Dynamics Laboratory. An overview of these atmospheric electricity hazards to aircraft and their systems is presented with emphasis on electrical and electronic subsystems. The discussion includes reviewing some of the characteristics of lightning and static electrification, trends in weather and lightning-related mishaps, some specific threat mechanisms and susceptible aircraft subsystems and some of the present technology gaps. A roadmap (flow chart) is presented to show the direction needed to address these problems.

  12. Advanced materials for aircraft engine applications.

    Science.gov (United States)

    Backman, D G; Williams, J C

    1992-02-28

    A review of advances for aircraft engine structural materials and processes is presented. Improved materials, such as superalloys, and the processes for making turbine disks and blades have had a major impact on the capability of modern gas turbine engines. New structural materials, notably composites and intermetallic materials, are emerging that will eventually further enhance engine performance, reduce engine weight, and thereby enable new aircraft systems. In the future, successful aerospace manufacturers will combine product design and materials excellence with improved manufacturing methods to increase production efficiency, enhance product quality, and decrease the engine development cycle time.

  13. Aircraft vibration and flutter

    Directory of Open Access Journals (Sweden)

    R. R. Aggarwal

    1958-04-01

    Full Text Available "The paper outlines the theoretical and experimental procedure one has to adopt for flutter prevention during the various stages (project, design and prototype of the development of modern aircraft. With the advent of high speed, the aerodynamic coefficients have to be calculated with due regards to the effects of compressibility, finite aspect ratio of the lifting surfaces, sweep back and other peculiar shapes of the wings. The use of thin, small aspect ratio with external masses, necessitates the computation of higher frequency modes of vibration. Single degree of freedom flutter and the effect of control surface non-linearities has also become very important. Thus, it is shown how the availability of high speed computing machines, improved experimental technique for model and full scale testing has not kept pace with the uncertainties associated with the transonic speeds, low aspect ratio and the high frequency modes. Cross-checking of theoretical and experimental results at every stage seem to be the only answer."

  14. A high maintenance dose of clopidogrel improves short-term clinical outcomes in patients with acute coronary syndrome undergoing drug-eluting stent implantation

    Institute of Scientific and Technical Information of China (English)

    HAN Ya-ling; WANG Bin; LI Yi; XU Kai; WANG Shou-li; JING Quan-min; WANG Zu-lu; WANG Dong-mei; MA Ying-yan; WANG Geng

    2009-01-01

    Background Recurrent ischemic events occurred even during routine use of 75 mg clopidogrel in addition to aspirin,that indicated a potentially insufficient maintenance dosage of clopidogrel.The aim of the present study was to evaluate the short-term efficacy and safety of a 150 mg maintenance dose of clopidogrel following a 600 mg loading dose in patients with an acute coronary syndrome (ACS) undergoing drug eluting stent (DES) implantation.Methods Between November 2005 and November 2006,a total of 813 consecutive ACS patients undergoing DES implantation were enrolled.A 600 mg loading dose was administered before percutaneous coronary intervention (PCI) nd patients were randomized to receive clopidogrel 75 mg or 150 mg for 30 days in addition to 300 mg aspidn daily.Primary end points were the composite of cardiac death,non-fatal myocardial infarction (MI) and urgent target vessel revascularization (UTVR).Secondary end points included stent thrombosis (ST),major and minor bleeding events at 30days.Results At a follow-up period of 30 days,4 (1.0%) patients in the 150 mg group and 9 (2.2%) patients in the 75 mg group (P >0.05) reached the primary end points.There was no significant difference in the incidences of MI (0.5% vs1.2%,P >0.05),UTVR (0.7% vs 2.0%,P >0.05),and cardiac death (0.2% vs 0.2%,P >0.05) between the two groups.The incidence of ST (0 vs 1.5%,P <0.05) was significantly lower in the 150 mg group than that in the 75 mg group.There were no significant differences between both groups regarding the risk of major (0.2% vs 0,P >0.05) or minor (0.5% vs 0.2%,P >0.05) bleedings.Conclusion A high clopidogrel maintenance dose of 150 mg daily following a 600 mg loading dose for the first month after PCI procedure reduces the risk of ST and appears to be safe in patients with ACS undergoing DES implantation.

  15. Modern electronic maintenance principles

    CERN Document Server

    Garland, DJ

    2013-01-01

    Modern Electronic Maintenance Principles reviews the principles of maintaining modern, complex electronic equipment, with emphasis on preventive and corrective maintenance. Unfamiliar subjects such as the half-split method of fault location, functional diagrams, and fault finding guides are explained. This book consists of 12 chapters and begins by stressing the need for maintenance principles and discussing the problem of complexity as well as the requirements for a maintenance technician. The next chapter deals with the connection between reliability and maintenance and defines the terms fai

  16. Essentials of aircraft armaments

    CERN Document Server

    Kaushik, Mrinal

    2017-01-01

    This book aims to provide a complete exposure about armaments from their design to launch from the combat aircraft. The book details modern ammunition and their tactical roles in warfare. The proposed book discusses aerodynamics, propulsion, structural as well as navigation, control, and guidance of aircraft armament. It also introduces the various types of ammunition developed by different countries and their changing trends. The book imparts knowledge in the field of design, and development of aircraft armaments to aerospace engineers and covers the role of the United Nations in peacekeeping and disarmament. The book will be very useful to researchers, students, and professionals working in design and manufacturing of aircraft armaments. The book will also serve air force and naval aspirants, and those interested in working on defence research and developments organizations. .

  17. Aircraft Fire Protection Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Navy Aircraft Protection Laboratory provides complete test support for all Navy air vehicle fire protection systems. The facility allows for the simulation of a...

  18. Aircraft Fire Protection Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Navy Aircraft Protection Laboratory provides complete test support for all Navy air vehicle fire protection systems.The facility allows for the simulation of a...

  19. Solar thermal aircraft

    Science.gov (United States)

    Bennett, Charles L.

    2007-09-18

    A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

  20. Aircraft electromagnetic compatibility

    Science.gov (United States)

    Clarke, Clifton A.; Larsen, William E.

    1987-06-01

    Illustrated are aircraft architecture, electromagnetic interference environments, electromagnetic compatibility protection techniques, program specifications, tasks, and verification and validation procedures. The environment of 400 Hz power, electrical transients, and radio frequency fields are portrayed and related to thresholds of avionics electronics. Five layers of protection for avionics are defined. Recognition is given to some present day electromagnetic compatibility weaknesses and issues which serve to reemphasize the importance of EMC verification of equipment and parts, and their ultimate EMC validation on the aircraft. Proven standards of grounding, bonding, shielding, wiring, and packaging are laid out to help provide a foundation for a comprehensive approach to successful future aircraft design and an understanding of cost effective EMC in an aircraft setting.

  1. Depreciation of aircraft

    Science.gov (United States)

    Warner, Edward P

    1922-01-01

    There is a widespread, and quite erroneous, impression to the effect that aircraft are essentially fragile and deteriorate with great rapidity when in service, so that the depreciation charges to be allowed on commercial or private operation are necessarily high.

  2. Predictors of improvement in subjective sleep quality reported by older adults following group-based cognitive behavior therapy for sleep maintenance and early morning awakening insomnia.

    Science.gov (United States)

    Lovato, Nicole; Lack, Leon; Wright, Helen; Kennaway, David J

    2013-09-01

    Cognitive behavior therapy is an effective nonpharmacologic treatment for insomnia. However, individualized administration is costly and often results in substantial variability in treatment response across individual patients, particularly so for older adults. Group-based administration has demonstrated impressive potential for a brief and inexpensive answer to the effective treatment of insomnia in the older population. It is important to identify potential predictors of response to such a treatment format to guide clinicians when selecting the most suitable treatment for their patients. The aim of our study was to identify factors that predict subjective sleep quality of older adults following group-based administration of cognitive behavior therapy for insomnia (CBT-I). Eighty-six adults (41 men; mean age, 64.10 y; standard deviation [SD], 6.80) with sleep maintenance or early morning awakening insomnia were selected from a community-based sample to participate in a 4-week group-based treatment program of CBT-I. Participants were required to complete 7-day sleep diaries and a comprehensive battery of questionnaires related to sleep quality and daytime functioning. Hierarchical multiple regression analyses were used to identify factors predicting subjective sleep quality immediately following treatment and at 3-month follow-up. Sleep diaries reported average nightly sleep efficiency (SE), which was used as the outcome measure of sleep quality. Participants with the greatest SE following treatment while controlling for pretreatment SE were relatively younger and had more confidence in their ability to sleep at pretreatment. These characteristics may be useful to guide clinicians when considering the use of a group-based CBT-I for sleep maintenance or early morning awakening insomnia in older adults. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Combination of low O(2) concentration and mesenchymal stromal cells during culture of cord blood CD34(+) cells improves the maintenance and proliferative capacity of hematopoietic stem cells.

    Science.gov (United States)

    Hammoud, Mohammad; Vlaski, Marija; Duchez, Pascale; Chevaleyre, Jean; Lafarge, Xavier; Boiron, Jean-Michel; Praloran, Vincent; Brunet De La Grange, Philippe; Ivanovic, Zoran

    2012-06-01

    The physiological approach suggests that an environment associating the mesenchymal stromal cells (MSC) and low O(2) concentration would be most favorable for the maintenance of hematopoietic stem cells (HSCs) in course of ex vivo expansion of hematopoietic grafts. To test this hypothesis, we performed a co-culture of cord blood CD34(+) cells with or without MSC in presence of cytokines for 10 days at 20%, 5%, and 1.5% O(2) and assessed the impact on total cells, CD34(+) cells, committed progenitors (colony-forming cells-CFC) and stem cells activity (pre-CFC and Scid repopulating cells-SRC). Not surprisingly, the expansion of total cells, CD34(+) cells, and CFC was higher in co-culture and at 20% O(2) compared to simple culture and low O(2) concentrations, respectively. However, co-culture at low O(2) concentrations provided CD34(+) cell and CFC amplification similar to classical culture at 20% O(2) . Interestingly, low O(2) concentrations ensured a better pre-CFC and SRC preservation/expansion in co-culture. Indeed, SRC activity in co-culture at 1.5% O(2) was higher than in freshly isolated CD34(+) cells. Interleukin-6 production by MSC at physiologically low O(2) concentrations might be one of the factors mediating this effect. Our data demonstrate that association of co-culture and low O(2) concentration not only induces sufficient expansion of committed progenitors (with respect to the classical culture), but also ensures a better maintenance/expansion of hematopoietic stem cells (HSCs), pointing to the oxygenation as a physiological regulatory factor but also as a cell engineering tool.

  4. METHODICAL SUPPORT OF AIRCRAFT WITH THE DELAYED DAMAGE SAFE FLIGHTS

    Directory of Open Access Journals (Sweden)

    Yuriy Michaylovic Chinyuchin

    2017-01-01

    Full Text Available The article deals with procedural guidelines for delayed damage aircraft safe flights. This methodological support is intended to form the aircraft type minimum equipment list (MEL.It is suggested to use airworthiness provision as the basic criterion for MEL determination. In order to develop methodological support of safe flights with delayed damage it is suggested to follow the well-known methods of statistical and constructive analyses and theory of estimation methods. Functional system reliability of delayed damage flights isanalyzed alongside with functional system failure types and consequences.Modeling reckons upon the opportunity to analyze the functional system failure-free operation for any predetermined specified operation time, including the time between overhauls. Functional system failure-free operation analyses and estima- tion by means of suggested model supposes step-by-step approach in solvation of the following problems: every component of the functional system reliability estimation; failure-free operation of the functional system in the whole.Thus it is possible to determine and forecast acceptable rates of failure probability for every analyzed component considering airworthiness requirements at the aircraft maintenance facility.The initial data for modeling is the functional systems and parts failure statistic database accumulated from a cer- tain maintenance facility operation experience.The suggested mathematical support for MEL formation allows to update manufacturer specified MEL for the air-craft maintenance facility.

  5. Knowledge based maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, A. [Hamburgische Electacitaets-Werke AG Hamburg (Germany)

    1997-12-31

    The establishment of maintenance strategies is of crucial significance for the reliability of a plant and the economic efficiency of maintenance measures. Knowledge about the condition of components and plants from the technical and business management point of view therefore becomes one of the fundamental questions and the key to efficient management and maintenance. A new way to determine the maintenance strategy can be called: Knowledge Based Maintenance. A simple method for determining strategies while taking the technical condition of the components of the production process into account to the greatest possible degree which can be shown. A software with an algorithm for Knowledge Based Maintenance leads the user during complex work to the determination of maintenance strategies for this complex plant components. (orig.)

  6. Automatic aircraft recognition

    Science.gov (United States)

    Hmam, Hatem; Kim, Jijoong

    2002-08-01

    Automatic aircraft recognition is very complex because of clutter, shadows, clouds, self-occlusion and degraded imaging conditions. This paper presents an aircraft recognition system, which assumes from the start that the image is possibly degraded, and implements a number of strategies to overcome edge fragmentation and distortion. The current vision system employs a bottom up approach, where recognition begins by locating image primitives (e.g., lines and corners), which are then combined in an incremental fashion into larger sets of line groupings using knowledge about aircraft, as viewed from a generic viewpoint. Knowledge about aircraft is represented in the form of whole/part shape description and the connectedness property, and is embedded in production rules, which primarily aim at finding instances of the aircraft parts in the image and checking the connectedness property between the parts. Once a match is found, a confidence score is assigned and as evidence in support of an aircraft interpretation is accumulated, the score is increased proportionally. Finally a selection of the resulting image interpretations with the highest scores, is subjected to competition tests, and only non-ambiguous interpretations are allowed to survive. Experimental results demonstrating the effectiveness of the current recognition system are given.

  7. The maintenance management for lean organization

    Directory of Open Access Journals (Sweden)

    Daniel D. GEORGESCU

    2010-12-01

    Full Text Available The goal of lean maintenance approach is to maintain organization international competitiveness. In the spirit of continuously improvement, in the paper it is shown how by adjusting some Lean manufacturing specific techniques for Total Productive Maintenance (TPM system, was born new maintenance system named Lean TPM. This is a systemic approach with three techniques, which don’t exclude specific techniques of TPM pillars, but complete them: the 7Ss as a critical first step in any improvement program; instantaneous maintenance; improvement setup operations. In the spirit of Lean principle, Lean TPM adjusts overall equipment effectiveness concept for all supply-chain from supplier to customer. Maintaining equipment in its optimal state and continually improving its productivity is the whole strategy behind Lean TPM.

  8. Operations and maintenance - Safety challenges

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Liv [Oljedirektoratet, Stavanger (Norway)

    1999-07-01

    With the unsteady oil prices and the possible consequences of the deregulation of the European energy markets one may expect further optimization of operating and maintenance costs. One may also expect extended use of various risk-based optimization techniques such as RCM (Reliability Centered Maintenance) and RBI (Risk Based Inspection). This presentation addresses the need for further research and development in this area. Maintenance work is necessary, but it can also create risk. The accident statistics show many examples of this. The Norwegian petroleum industry's ability to learn from previous incidents is questioned. Maintenance staff must be well trained and possess the necessary routines. Technical documentation must be updated. Uncertainties with respect to future oil and gas prices combined with the effect of the deregulation of the European energy markets will lead to even more focus on cost-effective operations and maintenance. The need for long-term research and development is stressed. Risk based techniques such as RCM and RBI are extensively used in the defence industry and the nuclear industry, but applying them to the petroleum industry requires improved risk models. Ageing effects such as corrosion, erosion, fatigue etc. can be expected, but the capability to predict, monitor and control them should be improved. At present, not even the most sophisticated risk analysis can model ageing effects. The importance of efficient use of information technology (IT) is stressed. Improving the product quality and safety often requires new technology and so research and development is important. Close cooperation with the industry is required.

  9. Myths and realities of electronics maintenance.

    Science.gov (United States)

    Harris, Douglas H

    2008-06-01

    The author presents and discusses discoveries and developments contributing to enhanced electronics maintenance performance. This body of research is viewed from the vantage point of Nick Bond's 1970 Ely Award-winning article in Human Factors, "Some Persistent Myths About Military Electronics Maintenance." Bond identified a set of myths and summarized research that not only produced information and techniques leading to demonstrably improved maintenance performance but also exploded many unfounded beliefs that were commonly held before the research had been conducted and the findings disseminated. The period from 1964 through 1986, as reflected by publications in the journal, was a productive period of research that led to greater understanding of human factors in electronics maintenance and to numerous advances that contributed, ultimately, to more effective maintenance performance. Technological advances, combined with what we learned about maintenance performance, have substantially reduced the maintenance burden and enhanced the maintenance of electronic systems. Some of the principal lessons learned from this research on electronics maintenance apply to understanding the effects of equipment complexity, providing an optimal role for automation, designing more appropriate on-the-job training, and enhancing troubleshooting skills.

  10. Fuel consumption and exhaust emissions of aircrafts

    Energy Technology Data Exchange (ETDEWEB)

    Buechler, R. [Institute of Flightmechanics, Braunschweig (Germany)

    1997-12-31

    The reduction of contamination of sensitive atmospheric layers by improved flight planning steps, is investigated. Calculated results have shown, that a further development of flight track planning allows considerable improvements on fuel consumption and exhaust emissions. Even if air traffic will further increase, optimistic investigations forecast a reduction of the environmental damage by aircraft exhausts, if the effects of improved flight track arrangement and engine innovations will be combined. (R.P.) 4 refs.

  11. Modeling Programs Increase Aircraft Design Safety

    Science.gov (United States)

    2012-01-01

    aircraft to safe flight. Today, all aircraft must have a flutter boundary 15 percent beyond the aircraft s expected maximum speed to ensure that flutter conditions are not encountered in flight. NASA continues to support research in new aircraft designs to improve knowledge of aeroelasticity and flutter. Through platforms such as Dryden Flight Research Center s Active Aeroelastic Wing (AAW) research aircraft, the Agency researches methods for in-flight validation of predictions and for controlling and taking advantage of aeroelastic conditions to enhance aircraft performance.

  12. A passive heat maintenance strategy implemented during a simulated half-time improves lower body power output and repeated sprint ability in professional Rugby Union players.

    Science.gov (United States)

    Russell, Mark; West, Daniel J; Briggs, Marc A; Bracken, Richard M; Cook, Christian J; Giroud, Thibault; Gill, Nicholas; Kilduff, Liam P

    2015-01-01

    Reduced physical performance has been observed following the half-time period in team sports players, likely due to a decrease in muscle temperature during this period. We examined the effects of a passive heat maintenance strategy employed between successive exercise bouts on core temperature (Tcore) and subsequent exercise performance. Eighteen professional Rugby Union players completed this randomised and counter-balanced study. After a standardised warm-up (WU) and 15 min of rest, players completed a repeated sprint test (RSSA 1) and countermovement jumps (CMJ). Thereafter, in normal training attire (Control) or a survival jacket (Passive), players rested for a further 15 min (simulating a typical half-time) before performing a second RSSA (RSSA 2) and CMJ's. Measurements of Tcore were taken at baseline, post-WU, pre-RSSA 1, post-RSSA 1 and pre-RSSA 2. Peak power output (PPO) and repeated sprint ability was assessed before and after the simulated half-time. Similar Tcore responses were observed between conditions at baseline (Control: 37.06±0.05°C; Passive: 37.03±0.05°C) and for all other Tcore measurements taken before half-time. After the simulated half-time, the decline in Tcore was lower (-0.74±0.08% vs. -1.54±0.06%, psprint times were 1.39±0.17% (prepeated sprint ability in professional Rugby Union players.

  13. Studying the Advance Maintenance Practice & Computerised Maintenance

    Directory of Open Access Journals (Sweden)

    Eng Hamdy Ibrahim Mohamed Mahmoud

    2016-02-01

    Full Text Available Many companieѕ think of maintenance aѕ an inevitable ѕource of coѕt. For theѕe companieѕ maintenance operationѕ have a corrective function and are only executed in emergency conditionѕ. Today, thiѕ form of intervention iѕ no longer acceptable becauѕe of certain critical elementѕ ѕuch aѕ product quality, plant ѕafety, and the increaѕe in maintenance department coѕtѕ which can repreѕent from 15 to 70% of total production coѕtѕ. The managerѕ have to ѕelect the beѕt maintenance policy for each piece of equipment or ѕyѕtem from a ѕet of poѕѕible alternativeѕ. For example, corrective, preventive, opportuniѕtic, condition-baѕed and predictive maintenance policieѕ are conѕidered in thiѕ paper.

  14. A randomized trail using motivational interviewing for maintenance of blood pressure improvements in a community-engaged lifestyle intervention: HUB City Steps

    Science.gov (United States)

    Background: Little is known about the effective dose of motivational interviewing for maintaining intervention-induced health outcome improvements. Purpose: To compare effects of two doses of motivational interviewing for maintaining blood pressure improvements in a community-engaged lifestyle int...

  15. A Randomized Trial Using Motivational Interviewing for Maintenance of Blood Pressure Improvements in a Community-Engaged Lifestyle Intervention: HUB City Steps

    Science.gov (United States)

    Landry, Alicia; Madson, Michael; Thomson, Jessica; Zoellner, Jamie; Connell, Carol; Yadrick, Kathleen

    2015-01-01

    Little is known about the effective dose of motivational interviewing for maintaining intervention-induced health outcome improvements. The purpose of this study was to compare effects of two doses of motivational interviewing for maintaining blood pressure improvements in a community-engaged lifestyle intervention conducted with…

  16. Random maintenance policies

    CERN Document Server

    Nakagawa, Toshio

    2014-01-01

    Exploring random maintenance models, this book provides an introduction to the implementation of random maintenance, and it is one of the first books to be written on this subject.  It aims to help readers learn new techniques for applying random policies to actual reliability models, and it provides new theoretical analyses of various models including classical replacement, preventive maintenance and inspection policies. These policies are applied to scheduling problems, backup policies of database systems, maintenance policies of cumulative damage models, and reliability of random redundant systems. Reliability theory is a major concern for engineers and managers, and in light of Japan’s recent earthquake, the reliability of large-scale systems has increased in importance. This also highlights the need for a new notion of maintenance and reliability theory, and how this can practically be applied to systems. Providing an essential guide for engineers and managers specializing in reliability maintenance a...

  17. Framework for Maintenance Planning

    DEFF Research Database (Denmark)

    Soares, C. Guedes; Duarte, J. Caldeira; Garbatov, Y.;

    2010-01-01

    The present document presents a framework for maintenance planning. Maintenance plays a fundamental role in counteracting degradation effects, which are present in all infrastructure and industrial products. Therefore, maintenance planning is a very critical aspect to consider both during...... the design and during the whole life span of operational use, within an integrated framework founded on risk and reliability based techniques. The document addresses designers, decision makers and professionals responsible for or involved in establishing maintenance plans. The purpose of this document...... is to present maintenance as an integrated approach that needs to be planned, designed, engineered, and controlled by proper qualitative and quantitative techniques. This document outlines the basic premises for maintenance planning and provides the general philosophies that can be followed and points to a best...

  18. Framework for Maintenance Planning

    DEFF Research Database (Denmark)

    Duarte, J. Caldeira; Garbatov, Y.; Zio, E.

    2010-01-01

    The present document presents a framework for maintenance planning. Maintenance plays a fundamental role in counteracting degradation effects, which are present in all infrastructure and industrial products. Therefore, maintenance planning is a very critical aspect to consider both during...... the design and during the whole life span of operational use, within an integrated framework founded on risk and reliability based techniques. The document addresses designers, decision makers and professionals responsible for or involved in establishing maintenance plans. The purpose of this document...... is to present maintenance as an integrated approach that needs to be planned, designed, engineered, and controlled by proper qualitative and quantitative techniques. This document outlines the basic premises for maintenance planning and provides the general philosophies that can be followed and points to a best...

  19. 基于PDA的航空机务维修信息系统设计%Design of Aviation Maintenance Information System Based on PDA

    Institute of Scientific and Technical Information of China (English)

    符永鹏; 张焰; 宿春晓; 孟晓滨

    2011-01-01

    Our military aircraft maintenance engineers have successfully developed a portable system named "Skilled Maintenance Engineer" Personal Digital Assistant (PDA) capable of analyzing aircraft failures, which for the first time Palm PC is used in the field of aviation maintenance. The system which based on Windows CE embedded OS is safe, secret and extendible because of many a innovation adopted. The application shows that this system provides friendly man - machine interface, easy for operation and stable in performance, It has greatly improved the efficiency of the military aircraft maintenance engineers. The technology and methods adopted in the system are worthy of being used extensively.%"机务通"个人数字助理(PDA)是首次将掌上电脑技术应用于航空机务维修领域并为军方的机务维护人员研制出的一套便携式机务维修及故障信息分析系统;该系统基于WindowsCE嵌入式操作系统,由于采用了多项创新技术,使系统具有良好的安全性、保密性和扩展性;应用结果表明,该系统人机界面友好,操作方便快捷,性能稳定可靠,大大提高了我军航空机务维修人员的工作效率,并具有一定的推广价值.

  20. The Effect of Reducing Cruise Altitude on the Topology and Emissions of a Commercial Transport Aircraft

    OpenAIRE

    2010-01-01

    In recent years, research has been conducted for alternative commercial transonic aircraft design configurations, such as the strut- braced wing and the truss-braced wing aircraft designs, in order to improve aircraft performance and reduce the impact of aircraft emissions as compared to a typical cantilever wing design. Research performed by Virginia Tech in conjunction with NASA Langley Research Center shows that these alternative configurations result in 20% or more reduction in fuel...

  1. Electromagnetic-Repulsion Systems For Deicing Aircraft

    Science.gov (United States)

    Smith, Samuel O.; Zieve, Peter

    1994-01-01

    Improved eddy-current electromagnetic-repulsion deicing systems developed for use on variety of exterior aircraft surfaces like leading edges of wings, engine inlets, propellers, and helicopter rotors. Fit to exterior surfaces, as retrofits or original equipment. Systems light in weight, consume little average power, and capable of protecting against severe icing conditions.

  2. Software evolution and maintenance

    CERN Document Server

    Tripathy, Priyadarshi

    2014-01-01

    Software Evolution and Maintenance: A Practitioner's Approach is an accessible textbook for students and professionals, which collates the advances in software development and provides the most current models and techniques in maintenance.Explains two maintenance standards: IEEE/EIA 1219 and ISO/IEC14764Discusses several commercial reverse and domain engineering toolkitsSlides for instructors are available onlineInformation is based on the IEEE SWEBOK (Software Engineering Body of Knowledge)

  3. Remote Maintenance Monitoring System -

    Data.gov (United States)

    Department of Transportation — The Remote Maintenance and Monitoring System (RMMS) is a collection of subsystems that includes telecommunication components, hardware, and software, which serve to...

  4. Software Maintenance Success Recipes

    CERN Document Server

    Reifer, Donald J

    2011-01-01

    Dispelling much of the folklore surrounding software maintenance, Software Maintenance Success Recipes identifies actionable formulas for success based on in-depth analysis of more than 200 real-world maintenance projects. It details the set of factors that are usually present when effective software maintenance teams do their work and instructs on the methods required to achieve success. Donald J. Reifer--an award winner for his contributions to the field of software engineering and whose experience includes managing the DoD Software Initiatives Office--provides step-by-step guidance on how t

  5. Aircraft Operations Classification System

    Science.gov (United States)

    Harlow, Charles; Zhu, Weihong

    2001-01-01

    Accurate data is important in the aviation planning process. In this project we consider systems for measuring aircraft activity at airports. This would include determining the type of aircraft such as jet, helicopter, single engine, and multiengine propeller. Some of the issues involved in deploying technologies for monitoring aircraft operations are cost, reliability, and accuracy. In addition, the system must be field portable and acceptable at airports. A comparison of technologies was conducted and it was decided that an aircraft monitoring system should be based upon acoustic technology. A multimedia relational database was established for the study. The information contained in the database consists of airport information, runway information, acoustic records, photographic records, a description of the event (takeoff, landing), aircraft type, and environmental information. We extracted features from the time signal and the frequency content of the signal. A multi-layer feed-forward neural network was chosen as the classifier. Training and testing results were obtained. We were able to obtain classification results of over 90 percent for training and testing for takeoff events.

  6. Identification of Aircraft Hazards

    Energy Technology Data Exchange (ETDEWEB)

    K. Ashley

    2006-12-08

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2005 [DIRS 174235], Section 6.4.1). That determination was conservatively based upon limited knowledge of flight data in the area of concern and upon crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a monitored geologic repository (MGR) at Yucca Mountain, using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987 [DIRS 103124], Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. The intended use of this report is to provide inputs for further screening and analysis of identified aircraft hazards based upon the criteria that apply to Category 1 and Category 2 event sequence analyses as defined in 10 CFR 63.2 [DIRS 176544] (Section 4). The scope of this report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the repository at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (Section 7).

  7. IDENTIFICATION OF AIRCRAFT HAZARDS

    Energy Technology Data Exchange (ETDEWEB)

    K.L. Ashley

    2005-03-23

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in the ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2004, Section 6.4.1). That determination was conservatively based on limited knowledge of flight data in the area of concern and on crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a Monitored Geologic Repository (MGR) at Yucca Mountain using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987, Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. NUREG-0800 is being used here as a reference because some of the same considerations apply. The intended use of this report is to provide inputs for further screening and analysis of the identified aircraft hazards based on the criteria that apply to Category 1 and 2 event sequence analyses as defined in 10 CFR 63.2 (see Section 4). The scope of this technical report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the MGR at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (see Section 7).

  8. High performance forward swept wing aircraft

    Science.gov (United States)

    Koenig, David G. (Inventor); Aoyagi, Kiyoshi (Inventor); Dudley, Michael R. (Inventor); Schmidt, Susan B. (Inventor)

    1988-01-01

    A high performance aircraft capable of subsonic, transonic and supersonic speeds employs a forward swept wing planform and at least one first and second solution ejector located on the inboard section of the wing. A high degree of flow control on the inboard sections of the wing is achieved along with improved maneuverability and control of pitch, roll and yaw. Lift loss is delayed to higher angles of attack than in conventional aircraft. In one embodiment the ejectors may be advantageously positioned spanwise on the wing while the ductwork is kept to a minimum.

  9. Automated Methods to Maintain Aircraft Separation

    Science.gov (United States)

    Lauderdale, Todd

    2011-01-01

    The air traffic control system in the United States has a great track-record for safety. As more aircraft enter the system at a given time, the situation becomes more complex though. Researchers at NASA are attempting to leverage advances in many fields including optimization, data mining, and numerical modeling of systems to improve the air-transportation system maintaining safety while increasing throughput and reducing delays. This talk will give a brief overview of the research at NASA towards modernizing the air-transportation system. It will then focus on the specific area of automation tools for maintaining physical separation between aircraft known as Separation Assurance.

  10. Aerodynamic design trends for commercial aircraft

    Science.gov (United States)

    Hilbig, R.; Koerner, H.

    1986-01-01

    Recent research on advanced-configuration commercial aircraft at DFVLR is surveyed, with a focus on aerodynamic approaches to improved performance. Topics examined include transonic wings with variable camber or shock/boundary-layer control, wings with reduced friction drag or laminarized flow, prop-fan propulsion, and unusual configurations or wing profiles. Drawings, diagrams, and graphs of predicted performance are provided, and the need for extensive development efforts using powerful computer facilities, high-speed and low-speed wind tunnels, and flight tests of models (mounted on specially designed carrier aircraft) is indicated.

  11. Application of the JDL data fusion process model to hard/soft information fusion in the condition monitoring of aircraft

    Science.gov (United States)

    Bernardo, Joseph T.

    2014-05-01

    Hard/soft information fusion has been proposed as a way to enhance diagnostic capability for the condition monitoring of machinery. However, there is a limited understanding of where hard/soft information fusion could and should be applied in the condition monitoring of aircraft. Condition-based maintenance refers to the philosophy of performing maintenance when the need arises, based upon indicators of deterioration in the condition of the machinery. The addition of the multisensory capability of human cognition to electronic sensors may create a fuller picture of machinery condition. Since 1988, the Joint Directors of Laboratories (JDL) data fusion process model has served as a framework for information fusion research. Advances are described in the application of hard/soft information fusion in condition monitoring using terms that condition-based maintenance professionals in aviation will recognize. Emerging literature on hard/soft information fusion in condition monitoring is organized into the levels of the JDL data fusion process model. Gaps in the literature are identified, and the author's ongoing research is discussed. Future efforts will focus on building domain-specific frameworks and experimental design, which may provide a foundation for improving flight safety, increasing mission readiness, and reducing the cost of maintenance operations.

  12. Effective maintenance practices to manage system aging

    Science.gov (United States)

    Chockie, Alan; Bjorkelo, Kenneth

    A study for the Nuclear Regulatory Commission was recently undertaken to identify effective maintenance practices that could be adapted by the nuclear industry in the United States to assist in managing the aging degradation of plant systems and components. Four organizations were examined to assess the influence of maintenance programs on addressing the system and component aging degradation issues. An effective maintenance program was found to be essential to the management of system and component aging. Four key elements of an effective maintenance program that are important to an aging management were identified: (1) the selection of critical systems and components; (2) the development of an understanding of aging through the collection and analysis of equipment performance information; (3) the development of appropriate preventive and predictive maintenance tasks to manage equipment and system aging degradation; and (4) the use of feedback mechanisms to continuously improve the management of aging systems and components. These elements were found to be common to all four organizations.

  13. Dynamics and control of morphing aircraft

    Science.gov (United States)

    Seigler, Thomas Michael

    The following work is directed towards an evaluation of aircraft that undergo structural shape change for the purpose of optimized flight and maneuvering control authority. Dynamical equations are derived for a morphing aircraft based on two primary representations; a general non-rigid model and a multi-rigid-body. A simplified model is then proposed by considering the altering structural portions to be composed of a small number of mass particles. The equations are then extended to consider atmospheric flight representations where the longitudinal and lateral equations are derived. Two aspects of morphing control are considered. The first is a regulation problem in which it is desired to maintain stability in the presence of large changes in both aerodynamic and inertial properties. From a baseline aircraft model various wing planform designs were constructed using Datcom to determine the required aerodynamic contributions. Based on nonlinear numerical evaluations adequate stabilization control was demonstrated using a robust linear control design. In maneuvering, divergent characteristics were observed at high structural transition rates. The second aspect considered is the use of structural changes for improved flight performance. A variable span aircraft is then considered in which asymmetric wing extension is used to effect the rolling moment. An evaluation of the variable span aircraft is performed in the context of bank-to-turn guidance in which an input-output control law is implemented.

  14. Exploration on the Method of Improving the Teaching Quality of Equipment Electrical Control and Maintenance%提高《设备电气控制与维修》教学质量的方法探究

    Institute of Scientific and Technical Information of China (English)

    孙长永

    2013-01-01

      针对未来学生的就业形势,对于掌握电气控制方面的技术和知识是非常重要的。尤其是对于机电类专业的学生,可以学以致用。学生具备电气控制与维修的基本知识和基本技能,初步形成解决实际问题的能力,逐步培养学生的职业技能,提高全面素质,增强适应职业变化的能力。所以《设备电气控制与维修》是一门实践性很强的学科。%  Based on the employment situation for prospective students, it is very important to master the skills and knowledge of electrical control, especially for students of mechanical and electrical major, it can help them apply what they have learned. If students has basic knowledge and basic skills for electrical control and maintenance, they can initially form the ability to solve practical problems, gradually develop professional skills, improve overall quality, and enhance the ability to adapt to job changes. Equipment Electrical Control and Maintenance is a very practical subject.

  15. AIRTV: Broadband Direct to Aircraft

    Science.gov (United States)

    Sorbello, R.; Stone, R.; Bennett, S. B.; Bertenyi, E.

    2002-01-01

    Airlines have been continuously upgrading their wide-body, long-haul aircraft with IFE (in-flight entertainment) systems that can support from 12 to 24 channels of video entertainment as well as provide the infrastructure to enable in-seat delivery of email and internet services. This is a direct consequence of increased passenger demands for improved in-flight services along with the expectations that broadband delivery systems capable of providing live entertainment (news, sports, financial information, etc.) and high speed data delivery will soon be available. The recent events of Sept. 11 have slowed the airline's upgrade of their IFE systems, but have also highlighted the compelling need for broadband aeronautical delivery systems to include operational and safety information. Despite the impact of these events, it is estimated that by 2005 more than 3000 long haul aircraft (servicing approximately 1 billion passengers annually) will be fully equipped with modern IFE systems. Current aircraft data delivery systems, which use either Inmarsat or NATS, are lacking in bandwidth and consequently are unsuitable to satisfy passenger demands for broadband email/internet services or the airlines' burgeoning data requirements. Present live video delivery services are limited to regional coverage and are not readily expandable to global or multiregional service. Faced with a compelling market demand for high data transport to aircraft, AirTV has been developing a broadband delivery system that will meet both passengers' and airlines' needs. AirTV is a global content delivery system designed to provide a range of video programming and data services to commercial airlines. When AirTV is operational in 2004, it will provide a broadband connection directly to the aircraft, delivering live video entertainment, internet/email service and essential operational and safety data. The system has been designed to provide seamless global service to all airline routes except for those

  16. 老龄飞机结构的腐蚀问题与对策%Corrosion Problems and Countermeasures of the Aging Aircraft

    Institute of Scientific and Technical Information of China (English)

    陈群志; 王逾涯; 崔常京; 张蕾

    2014-01-01

    列举了某型老龄飞机腐蚀故障案例,阐明了老龄飞机结构腐蚀的共性问题及特点,从使用寿命期指标体系、结构抗腐蚀品质、服役环境、使用维护与腐蚀修理等方面较系统地分析了老龄飞机结构腐蚀的主要原因和影响因素。重点阐述了老龄飞机结构腐蚀防护对策与措施,主要包括结构腐蚀检查评估、涂层体系改进与结构密封防水改进、外场使用维护中腐蚀预防与控制措施。%Corrosion failure cases were listed for a certain type of aging aircraft structure. The common corrosion prob-lems and theirs characteristics of the aging aircraft structure were clarified. The main causes and impact factors of the aging aircraft structure corrosion were systematically analyzed from the index system of service life period, structure corrosion characteristics, service environment, corrosion maintenance during service and corrosion repair, etc. The aging aircraft structure corrosion protection countermeasures were emphatically elaborated, mainly including corrosion inspection evalua-tion, coating system improvement, waterproof sealing structure improvement, corrosion prevention and control measures during field use maintenance.

  17. A strategic planning methodology for aircraft redesign

    Science.gov (United States)

    Romli, Fairuz Izzuddin

    Due to a progressive market shift to a customer-driven environment, the influence of engineering changes on the product's market success is becoming more prominent. This situation affects many long lead-time product industries including aircraft manufacturing. Derivative development has been the key strategy for many aircraft manufacturers to survive the competitive market and this trend is expected to continue in the future. Within this environment of design adaptation and variation, the main market advantages are often gained by the fastest aircraft manufacturers to develop and produce their range of market offerings without any costly mistakes. This realization creates an emphasis on the efficiency of the redesign process, particularly on the handling of engineering changes. However, most activities involved in the redesign process are supported either inefficiently or not at all by the current design methods and tools, primarily because they have been mostly developed to improve original product development. In view of this, the main goal of this research is to propose an aircraft redesign methodology that will act as a decision-making aid for aircraft designers in the change implementation planning of derivative developments. The proposed method, known as Strategic Planning of Engineering Changes (SPEC), combines the key elements of the product redesign planning and change management processes. Its application is aimed at reducing the redesign risks of derivative aircraft development, improving the detection of possible change effects propagation, increasing the efficiency of the change implementation planning and also reducing the costs and the time delays due to the redesign process. To address these challenges, four research areas have been identified: baseline assessment, change propagation prediction, change impact analysis and change implementation planning. Based on the established requirements for the redesign planning process, several methods and

  18. A Risk Management Architecture for Emergency Integrated Aircraft Control

    Science.gov (United States)

    McGlynn, Gregory E.; Litt, Jonathan S.; Lemon, Kimberly A.; Csank, Jeffrey T.

    2011-01-01

    Enhanced engine operation--operation that is beyond normal limits--has the potential to improve the adaptability and safety of aircraft in emergency situations. Intelligent use of enhanced engine operation to improve the handling qualities of the aircraft requires sophisticated risk estimation techniques and a risk management system that spans the flight and propulsion controllers. In this paper, an architecture that weighs the risks of the emergency and of possible engine performance enhancements to reduce overall risk to the aircraft is described. Two examples of emergency situations are presented to demonstrate the interaction between the flight and propulsion controllers to facilitate the enhanced operation.

  19. Maintenance Trades Guidelines

    Science.gov (United States)

    Weidner, Theodore J.

    2008-01-01

    In 2002, APPA published "Maintenance Staffing Guidelines for Educational Facilities," the first building maintenance trades staffing guideline designed to assist educational facilities professionals with their staffing needs. addresses how facilities professionals can determine the appropriate size and mix of their organization. Contents…

  20. Design for air-to-air refuelling operations; new passenger and tanker aircraft design for AAR scenarios

    NARCIS (Netherlands)

    Li, M.O.

    2014-01-01

    Air-to-air refuelling is a way to improve fuel efficiency of the overall transport system without waiting for the improvement of basic aviation technology. To take full advantage of such an operation, both passenger aircraft and tanker aircraft (which deliver required fuel to the passenger aircraft