WorldWideScience

Sample records for comparing airframe design

  1. Bird or bat: comparing airframe design and flight performance.

    Science.gov (United States)

    Hedenström, Anders; Johansson, L Christoffer; Spedding, Geoffrey R

    2009-03-01

    Birds and bats have evolved powered flight independently, which makes a comparison of evolutionary 'design' solutions potentially interesting. In this paper we highlight similarities and differences with respect to flight characteristics, including morphology, flight kinematics, aerodynamics, energetics and flight performance. Birds' size range is 0.002-15 kg and bats' size range is 0.002-1.5 kg. The wingbeat kinematics differ between birds and bats, which is mainly due to the different flexing of the wing during the upstroke and constraints by having a wing of feathers and a skin membrane, respectively. Aerodynamically, bats appear to generate a more complex wake than birds. Bats may be more closely adapted for slow maneuvering flight than birds, as required by their aerial hawking foraging habits. The metabolic rate and power required to fly are similar among birds and bats. Both groups share many characteristics associated with flight, such as for example low amounts of DNA in cells, the ability to accumulate fat as fuel for hibernation and migration, and parallel habitat-related wing shape adaptations.

  2. The Study of Tactical Missile's Airframe Digital Optimization Design

    Institute of Scientific and Technical Information of China (English)

    LUO Zhiqing; QIAN Airong; LI Xuefeng; GAO Lin; LEI Jian

    2006-01-01

    Digital design and optimal are very important in modern design. The traditional design methods and procedure are not fit for the modern missile weapons research and development. Digital design methods and optimal ideas were employed to deal with this problem. The disadvantages of the traditional missile's airframe design procedure and the advantages of the digital design methods were discussed. A new concept of design process reengineering (DPR) was put forward. An integrated missile airframe digital design platform and the digital design procedure, which integrated the optimization ideas and methods, were developed. Case study showed that the design platform and the design procedure could improve the efficiency and quality of missile's airframe design, and get the more reasonable and optimal results.

  3. Topology Optimization as a Conceptual Tool for Designing New Airframes

    OpenAIRE

    2016-01-01

    During the two last decades, topology optimization has grown to be an accepted and used method to produce conceptual designs. Topology optimization is traditionally carried out on a component level, but in this project, the possibility to apply it to airframe design on a full scale aeroplane model is evaluated. The project features a conceptual flying-wing design on which the study is to be carried out. Inertia Relief is used to constrain the aeroplane instead of traditional single point cons...

  4. Toward the direct design of waverider airframes

    Science.gov (United States)

    Kinsey, Dawn Daniel

    1998-12-01

    A waverider is a hypersonic vehicle that keeps the bow shock attached to its leading edges. This class of vehicles originated in the late 1950's as a theoretical construct. Since the late 1980's there has been a resurgence of waverider research and an explosion of waverider applications. Waveriders have traditionally been and are still primarily designed using inverse methods, wherein the flowfield is known and the body surfaces are formed by collecting streamlines or streamsurfaces out of the flowfield. In the work presented here, the advantages of using a more conventional direct-design method for waveriders are investigated. The tools necessary to construct a practical Computational Fluid Dynamics design code are evaluated. As a start, a 3-D steady Euler code is built. The code uses an adaptive Cartesian mesh which allows arbitrary body shapes. The strengths and weaknesses of the code and direct-design method will be discussed. Several test cases and a simple design study are performed. These show that off-design conditions are easily simulated. A case study reveals that small changes in the body shape can significantly impact the lift-to-drag ratio. This points to an advantage of the direct-design method. Because the direct method does not constrain the design space, it can be used to look for optimum shapes between those found using inverse methods.

  5. Should we attempt global (inlet engine airframe) control design?

    Science.gov (United States)

    Carlin, C. M.

    1980-01-01

    The feasibility of multivariable design of the entire airplane control system is briefly addressed. An intermediate step in that direction is to design a control for an inlet engine augmentor system by using multivariable techniques. The supersonic cruise large scale inlet research program is described which will provide an opportunity to develop, integrate, and wind tunnel test a control for a mixed compression inlet and variable cycle engine. The integrated propulsion airframe control program is also discussed which will introduce the problem of implementing MVC within a distributed processing avionics architecture, requiring real time decomposition of the global design into independent modules in response to hardware communication failures.

  6. Design and Test of an Improved Crashworthiness Small Composite Airframe

    Science.gov (United States)

    Terry, James E.; Hooper, Steven J.; Nicholson, Mark

    2002-01-01

    The purpose of this small business innovative research (SBIR) program was to evaluate the feasibility of developing small composite airplanes with improved crashworthiness. A combination of analysis and half scale component tests were used to develop an energy absorbing airframe. Four full scale crash tests were conducted at the NASA Impact Dynamics Research Facility, two on a hard surface and two onto soft soil, replicating earlier NASA tests of production general aviation airplanes. Several seat designs and restraint systems including both an air bag and load limiting shoulder harnesses were tested. Tests showed that occupant loads were within survivable limits with the improved structural design and the proper combination of seats and restraint systems. There was no loss of cabin volume during the events. The analysis method developed provided design guidance but time did not allow extending the analysis to soft soil impact. This project demonstrated that survivability improvements are possible with modest weight penalties. The design methods can be readily applied by airplane designers using the examples in this report.

  7. Investigation on the use of optimization techniques for helicopter airframe vibrations design studies

    Science.gov (United States)

    Sreekanta Murthy, T.

    1992-01-01

    Results of the investigation of formal nonlinear programming-based numerical optimization techniques of helicopter airframe vibration reduction are summarized. The objective and constraint function and the sensitivity expressions used in the formulation of airframe vibration optimization problems are presented and discussed. Implementation of a new computational procedure based on MSC/NASTRAN and CONMIN in a computer program system called DYNOPT for optimizing airframes subject to strength, frequency, dynamic response, and dynamic stress constraints is described. An optimization methodology is proposed which is thought to provide a new way of applying formal optimization techniques during the various phases of the airframe design process. Numerical results obtained from the application of the DYNOPT optimization code to a helicopter airframe are discussed.

  8. Calculation of rotor impedance for use in design analysis of helicopter airframe vibrations

    Science.gov (United States)

    Nygren, Kip P.

    1990-01-01

    Excessive vibration is one of the most prevalent technical obstacles encountered in the development of new rotorcraft. The inability to predict these vibrations is primarily due to deficiencies in analysis and simulation tools. The Langley Rotorcraft Structural Dynamics Program was instituted in 1984 to meet long term industry needs in the area of rotorcraft vibration prediction. As a part of the Langley program, this research endeavors to develop an efficient means of coupling the rotor to the airframe for preliminary design analysis of helicopter airframe vibrations. The main effort was to modify the existing computer program for modeling the dynamic and aerodynamic behavior of rotorcraft called DYSCO (DYnamic System COupler) to calculate the rotor impedance. DYSCO was recently developed for the U.S. Army and has proven to be adaptable for the inclusion of new solution methods. The solution procedure developed to use DYSCO for the calculation of rotor impedance is presented. Verification of the procedure by comparison with a known solution for a simple wind turbine model is about 75 percent completed, and initial results are encouraging. After the wind turbine impedance is confirmed, the verification effort will continue by comparison to solutions of a more sophisticated rotorcraft model. Future work includes determination of the sensitivity of the rotorcraft airframe vibrations to helicopter flight conditions and rotor modeling assumptions. When completed, this research will ascertain the feasibility and efficiency of the impedance matching method of rotor-airframe coupling for use in the analysis of airframe vibrations during the preliminary rotorcraft design process.

  9. Global-local Knowledge Coupling Approach to Support Airframe Structural Design

    NARCIS (Netherlands)

    Wang, H.

    2014-01-01

    The outsourcing that has taken place in the aircraft industry over the last few decades has created a globalized supply chain from and to a limited number of original equipment manufacturers (OEMs). This has led to multi-level design due to the shift from airframe subsystem design to suppliers.

  10. Global-local Knowledge Coupling Approach to Support Airframe Structural Design

    NARCIS (Netherlands)

    Wang, H.

    2014-01-01

    The outsourcing that has taken place in the aircraft industry over the last few decades has created a globalized supply chain from and to a limited number of original equipment manufacturers (OEMs). This has led to multi-level design due to the shift from airframe subsystem design to suppliers. Incr

  11. The Engineering Design of Engine/Airframe Integration for the SAENGER Fully Reusable Space Transportation System

    Science.gov (United States)

    2010-09-01

    Z39-18 1.0 THE GERMAN HYPERSONICS TECHNOLOGY PROGRAM (1988-1995) Fig. 01 SÄNGER/ HTP : Schedule of the German Hypersonics Activities In Germany...Concept Study Preliminary Study  System Study  Propulsion Study  Concept Studies  Basic Technologies  Test facilities  Techn. Dev.+Verific. Concept...Flight Test Vehicle Study  RAM-Engine Dev./Ground Test , SCRAM  Materials/Structures Technology The Engineering Design of Engine/Airframe

  12. Aerodynamic Design of the Hybrid Wing Body Propulsion-Airframe Integration

    Science.gov (United States)

    Liou, May-Fun; Kim, Hyoungjin; Lee, ByungJoon; Liou, Meng-Sing

    2017-01-01

    A hybrid wingbody (HWB) concept is being considered by NASA as a potential subsonic transport aircraft that meets aerodynamic, fuel, emission, and noise goals in the time frame of the 2030s. While the concept promises advantages over conventional wing-and-tube aircraft, it poses unknowns and risks, thus requiring in-depth and broad assessments. Specifically, the configuration entails a tight integration of the airframe and propulsion geometries; the aerodynamic impact has to be carefully evaluated. With the propulsion nacelle installed on the (upper) body, the lift and drag are affected by the mutual interference effects between the airframe and nacelle. The static margin for longitudinal stability is also adversely changed. We develop a design approach in which the integrated geometry of airframe (HWB) and propulsion is accounted for simultaneously in a simple algebraic manner, via parameterization of the planform and airfoils at control sections of the wingbody. In this paper, we present the design of a 300-passenger transport that employs distributed electric fans for propulsion. The trim for stability is achieved through the use of the wingtip twist angle. The geometric shape variables are determined through the adjoint optimization method by minimizing the drag while subject to lift, pitch moment, and geometry constraints. The design results clearly show the influence on the aerodynamic characteristics of the installed nacelle and trimming for stability. A drag minimization with the trim constraint yields a reduction of 10 counts in the drag coefficient.

  13. Structural-Acoustic Simulations in Early Airframe Design Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The structural design during the early development of an aircraft focuses on strength, fatigue, corrosion, maintenance, inspection, and manufacturing. Usually the...

  14. The NASA/Industry Design Analysis Methods for Vibrations (DAMVIBS) Program - Boeing helicopters airframe finite element modeling

    Science.gov (United States)

    Gabel, R.; Lang, P.; Reed, D.

    1992-01-01

    Finite-element modeling of the airframe vibration of the Army/Boeing CH-47D helicopter is conducted with comparisons to experimental data in an effort to improve the design process. A NASTRAN FEM is developed that is fully representative of the test configuration and includes the support fixture, shakers, and the aircraft/shaker suspension system. The analysis is conducted with specific attention given to the prediction of reasonable forced amplitudes throughout the airframe. Reasonable correlation is noted between the FEM and experimental results, although improved correlation can be obtained by including more accurate damping values and secondary effects such as stringer shear loading. It is shown that the general stress model does not provide an adequate dynamic analysis on which to base design improvements. A more detailed model is required that emphasizes highly detailed helicopter elements and employs a finer mesh particularly in the description of the mass distribution.

  15. Propulsion Airframe Aeroacoustics Technology Evaluation and Selection Using a Multi-Attribute Decision Making Process and Non-Deterministic Design

    Science.gov (United States)

    Burg, Cecile M.; Hill, Geoffrey A.; Brown, Sherilyn A.; Geiselhart, Karl A.

    2004-01-01

    The Systems Analysis Branch at NASA Langley Research Center has investigated revolutionary Propulsion Airframe Aeroacoustics (PAA) technologies and configurations for a Blended-Wing-Body (BWB) type aircraft as part of its research for NASA s Quiet Aircraft Technology (QAT) Project. Within the context of the long-term NASA goal of reducing the perceived aircraft noise level by a factor of 4 relative to 1997 state of the art, major configuration changes in the propulsion airframe integration system were explored with noise as a primary design consideration. An initial down-select and assessment of candidate PAA technologies for the BWB was performed using a Multi-Attribute Decision Making (MADM) process consisting of organized brainstorming and decision-making tools. The assessments focused on what effect the PAA technologies had on both the overall noise level of the BWB and what effect they had on other major design considerations such as weight, performance and cost. A probabilistic systems analysis of the PAA configurations that presented the best noise reductions with the least negative impact on the system was then performed. Detailed results from the MADM study and the probabilistic systems analysis will be published in the near future.

  16. The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) program: Boeing Helicopters airframe finite element modeling

    Science.gov (United States)

    Gabel, R.; Lang, P.; Reed, D.

    1993-01-01

    Mathematical models based on the finite element method of structural analysis, as embodied in the NASTRAN computer code, are routinely used by the helicopter industry to calculate airframe static internal loads used for sizing structural members. Historically, less reliance has been placed on the vibration predictions based on these models. Beginning in the early 1980's NASA's Langley Research Center initiated an industry wide program with the objective of engendering the needed trust in vibration predictions using these models and establishing a body of modeling guides which would enable confident future prediction of airframe vibration as part of the regular design process. Emphasis in this paper is placed on the successful modeling of the Army/Boeing CH-47D which showed reasonable correlation with test data. A principal finding indicates that improved dynamic analysis requires greater attention to detail and perhaps a finer mesh, especially the mass distribution, than the usual stress model. Post program modeling efforts show improved correlation placing key modal frequencies in the b/rev range with 4 percent of the test frequencies.

  17. Airframe/TPS Session

    Science.gov (United States)

    Welch, Sharon; Bowles, David

    2000-01-01

    This viewgraph presentation gives an overview of the second generation Reusable Launch Vehicle (RLV) airframe configuration, including details on the structures and materials, tanks, airframe/cryotank demonstrations, internal assemblies, weight growth and margin, and safety and cost requirements.

  18. Aerodynamic Design of Integrated Propulsion-Airframe Configuration of the Hybrid Wing-Body Aircraft

    Science.gov (United States)

    Liou, May-Fun; Kim, Hyoungjin; Lee, B. J.; Liou, Meng-Sing

    2017-01-01

    Hybrid Wing Body (HWB) aircraft is characterized by a flattened and airfoil-shaped body, which produces a substantial portion of the total lift. The body form is composed of distinct and separate wing structures, though the wings are smoothly blended into the body. This concept has been studied widely and results suggest remarkable performance improvements over the conventional tube and wing transport1,2. HWB incorporates design features from both a futuristic fuselage and flying wing design, which houses most of the crew, payload and equipment inside the main centerbody structure.

  19. Optimization of helicopter airframe structures for vibration reduction considerations, formulations and applications

    Science.gov (United States)

    Murthy, T. Sreekanta

    1988-01-01

    Several key issues involved in the application of formal optimization technique to helicopter airframe structures for vibration reduction are addressed. Considerations which are important in the optimization of real airframe structures are discussed. Considerations necessary to establish relevant set of design variables, constraints and objectives which are appropriate to conceptual, preliminary, detailed design, ground and flight test phases of airframe design are discussed. A methodology is suggested for optimization of airframes in various phases of design. Optimization formulations that are unique to helicopter airframes are described and expressions for vibration related functions are derived. Using a recently developed computer code, the optimization of a Bell AH-1G helicopter airframe is demonstrated.

  20. Control strategies for aircraft airframe noise reduction

    Institute of Scientific and Technical Information of China (English)

    Li Yong; Wang Xunnian; Zhang Dejiu

    2013-01-01

    With the development of low-noise aircraft engine,airframe noise now represents a major noise source during the commercial aircraft's approach to landing phase.Noise control efforts have therefore been extensively focused on the airframe noise problems in order to further reduce aircraft overall noise.In this review,various control methods explored in the last decades for noise reduction on airframe components including high-lift devices and landing gears are summarized.We introduce recent major achievements in airframe noise reduction with passive control methods such as fairings,deceleration plates,splitter plates,acoustic liners,slat cove cover and side-edge replacements,and then discuss the potential and control mechanism of some promising active flow control strategies for airframe noise reduction,such as plasma technique and air blowing/suction devices.Based on the knowledge gained throughout the extensively noise control testing,a few design concepts on the landing gear,high-lift devices and whole aircraft are provided for advanced aircraft low-noise design.Finally,discussions and suggestions are given for future research on airframe noise reduction.

  1. 2nd Generation RLV Airframe Structures and Materials

    Science.gov (United States)

    Johnson, Theodore F.

    2000-01-01

    The goals and objectives of the project summarized in this viewgraph presentation are the following: (1) Develop and demonstrate verified airframe and cryotank structural design and analysis technologies, including damage tolerance, safety, reliability, and residual strength technologies, robust nonlinear shell and cryotank analysis technologies, high-fidelity analysis and design technologies for local structural detail features and joints, and high-fidelity analysis technologies for sandwich structures; (2) Demonstrate low cost, robust materials and processing, including polymeric matrix composite (PMC) and metallic materials and processing, and refractory composite and metallic hot structures materials and processing; (3) Develop and demonstrate robust airframe structures and validated integrated airframe structural concepts, including low cost fabrication and joining, operations efficient designs and inspection techniques (non-destructive evaluation), scale-up and integrated thermal structure tests, and airframe structures IVHM; (4) Demonstrate low cost, robust repair techniques; and (5) Develop verified integrated airframe structural concepts, including integrated structural concepts.

  2. An artificial neural network approach for aerodynamic performance retention in airframe noise reduction design of a 3D swept wing model

    Institute of Scientific and Technical Information of China (English)

    Tao Jun; Sun Gang

    2016-01-01

    With the progress of high-bypass turbofan and the innovation of silencing nacelle in engine noise reduction, airframe noise has now become another important sound source besides the engine noise. Thus, reducing airframe noise makes a great contribution to the overall noise reduction of a civil aircraft. However, reducing airframe noise often leads to aerodynamic perfor-mance loss in the meantime. In this case, an approach based on artificial neural network is intro-duced. An established database serves as a basis and the training sample of a back propagation (BP) artificial neural network, which uses confidence coefficient reasoning method for optimization later on. Then the most satisfactory configuration is selected for validating computations through the trained BP network. On the basis of the artificial neural network approach, an optimization pro-cess of slat cove filler (SCF) for high lift devices (HLD) on the Trap Wing is presented. Aerody-namic performance of both the baseline and optimized configurations is investigated through unsteady detached eddy simulations (DES), and a hybrid method, which combines unsteady DES method with acoustic analogy theory, is employed to validate the noise reduction effect. The numerical results indicate not merely a significant airframe noise reduction effect but also excel-lent aerodynamic performance retention simultaneously.

  3. An artificial neural network approach for aerodynamic performance retention in airframe noise reduction design of a 3D swept wing model

    Directory of Open Access Journals (Sweden)

    Tao Jun

    2016-10-01

    Full Text Available With the progress of high-bypass turbofan and the innovation of silencing nacelle in engine noise reduction, airframe noise has now become another important sound source besides the engine noise. Thus, reducing airframe noise makes a great contribution to the overall noise reduction of a civil aircraft. However, reducing airframe noise often leads to aerodynamic performance loss in the meantime. In this case, an approach based on artificial neural network is introduced. An established database serves as a basis and the training sample of a back propagation (BP artificial neural network, which uses confidence coefficient reasoning method for optimization later on. Then the most satisfactory configuration is selected for validating computations through the trained BP network. On the basis of the artificial neural network approach, an optimization process of slat cove filler (SCF for high lift devices (HLD on the Trap Wing is presented. Aerodynamic performance of both the baseline and optimized configurations is investigated through unsteady detached eddy simulations (DES, and a hybrid method, which combines unsteady DES method with acoustic analogy theory, is employed to validate the noise reduction effect. The numerical results indicate not merely a significant airframe noise reduction effect but also excellent aerodynamic performance retention simultaneously.

  4. Fuel Efficiencies Through Airframe Improvements

    Science.gov (United States)

    Bezos-O'Connor, Gaudy M.; Mangelsdorf, Mark F.; Maliska, Heather A.; Washburn, Anthony E.; Wahls, Richard A.

    2011-01-01

    The factors of continuing strong growth in air traffic volume, the vital role of the air transport system on the economy, and concerns about the environmental impact of aviation have added focus to the National Aeronautics Research Policy. To address these concerns in the context of the National Policy, NASA has set aggressive goals in noise reduction, emissions, and energy consumption. With respect to the goal of reducing energy consumption in the fleet, the development of promising airframe technologies is required to realize the significant improvements that are desired. Furthermore, the combination of advances in materials and structures with aerodynamic technologies may lead to a paradigm shift in terms of potential configurations for the future. Some of these promising airframe technologies targeted at improved efficiency are highlighted.

  5. 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…

  6. Proceedings of the Airframe Icing Workshop

    Science.gov (United States)

    Colantonio, Ron O. (Editor)

    2009-01-01

    The NASA Glenn Research Center (GRC) has a long history of working with its partners towards the understanding of ice accretion formation and its associated degradation of aerodynamic performance. The June 9, 2009, Airframe Icing Workshop held at GRC provided an opportunity to examine the current NASA airframe icing research program and to dialogue on remaining and emerging airframe icing issues and research with the external community. Some of the airframe icing gaps identified included, but are not limited to, ice accretion simulation enhancements, three-dimensional benchmark icing database development, three-dimensional iced aerodynamics modeling, and technology development for a smart icing system.

  7. METHODS OF THE APPROXIMATE ESTIMATIONS OF FATIGUE DURABILITY OF COMPOSITE AIRFRAME COMPONENT TYPICAL ELEMENTS

    Directory of Open Access Journals (Sweden)

    V. E. Strizhius

    2015-01-01

    Full Text Available Methods of the approximate estimations of fatigue durability of composite airframe component typical elements which can be recommended for application at the stage of outline designing of the airplane are generated and presented.

  8. Airframe-Jet Engine Integration Noise

    Science.gov (United States)

    Tam, Christopher; Antcliff, Richard R. (Technical Monitor)

    2003-01-01

    It has been found experimentally that the noise radiated by a jet mounted under the wing of an aircraft exceeds that of the same jet in a stand-alone environment. The increase in noise is referred to as jet engine airframe integration noise. The objectives of the present investigation are, (1) To obtain a better understanding of the physical mechanisms responsible for jet engine airframe integration noise or installation noise. (2) To develop a prediction model for jet engine airframe integration noise. It is known that jet mixing noise consists of two principal components. They are the noise from the large turbulence structures of the jet flow and the noise from the fine scale turbulence. In this investigation, only the effect of jet engine airframe interaction on the fine scale turbulence noise of a jet is studied. The fine scale turbulence noise is the dominant noise component in the sideline direction. Thus we limit out consideration primarily to the sideline.

  9. Fluidic actuators for active flow control on airframe

    Science.gov (United States)

    Schueller, M.; Weigel, P.; Lipowski, M.; Meyer, M.; Schlösser, P.; Bauer, M.

    2016-04-01

    One objective of the European Projects AFLoNext and Clean Sky 2 is to apply Active Flow Control (AFC) on the airframe in critical aerodynamic areas such as the engine/wing junction or the outer wing region for being able to locally improve the aerodynamics in certain flight conditions. At the engine/wing junction, AFC is applied to alleviate or even eliminate flow separation at low speeds and high angle of attacks likely to be associated with the integration of underwing- mounted Ultra High Bypass Ratio (UHBR) engines and the necessary slat-cut-outs. At the outer wing region, AFC can be used to allow more aggressive future wing designs with improved performance. A relevant part of the work on AFC concepts for airframe application is the development of suitable actuators. Fluidic Actuated Flow Control (FAFC) has been introduced as a Flow Control Technology that influences the boundary layer by actively blowing air through slots or holes out of the aircraft skin. FAFC actuators can be classified by their Net Mass Flux and accordingly divided into ZNMF (Zero Net Mass Flux) and NZNMF (Non Zero Net-Mass-Flux) actuators. In the frame of both projects, both types of the FAFC actuator concepts are addressed. In this paper, the objectives of AFC on the airframe is presented and the actuators that are used within the project are discussed.

  10. 14 CFR Appendix C to Part 147 - Airframe Curriculum Subjects

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airframe Curriculum Subjects C Appendix C... Appendix C to Part 147—Airframe Curriculum Subjects This appendix lists the subjects required in at least 750 hours of each airframe curriculum, in addition to at least 400 hours in general curriculum...

  11. Plan, formulate, discuss and correlate a NASTRAN finite element vibrations model of the Boeing Model 360 helicopter airframe

    Science.gov (United States)

    Gabel, R.; Lang, P. F.; Smith, L. A.; Reed, D. A.

    1989-01-01

    Boeing Helicopter, together with other United States helicopter manufacturers, participated in a finite element applications program to emplace in the United States a superior capability to utilize finite element analysis models in support of helicopter airframe design. The activities relating to planning and creating a finite element vibrations model of the Boeing Model 36-0 composite airframe are summarized, along with the subsequent analytical correlation with ground shake test data.

  12. Applications of virtual manufacturing in composite airframe structure assembly

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D.E.; Hahn, H.T. [Univ. of California, Los Angeles, CA (United States). School of Engineering and Applied Sciences

    1995-12-31

    In order to produce composite airframe structures cost-effectively and time-efficiently, quantitative and qualitative tools for composite virtual manufacturing (CVM) are being applied to analyze assembly problems based on a concurrent engineering approach. This approach to product development stresses the importance of bringing together integrated product and process development teams (IPPDT) to rapidly design, manufacture and ship cost-competitive transportation systems. Virtual manufacturing tools are being used to employ an integrated set of process models and product data information to simulate the processes required to fabricate composite aircraft structures. By coupling both product and process development, different members of the IPPDT can be provided with information important to assessing potential assembly problems prior to actual product manufacture. Quantitative measures of component deformations and contact conditions are computed to analyze the forces and alignments required for airframe assembly. By minimizing problems prior to actual physical assembly and designing composite aircraft structures that can be easily manufactured and assembled, different aircraft design variations are evaluated and produced to meet specific cost and time constraints.

  13. Mechanical Properties and Fatigue Behavior of Unitized Composite Airframe Structures at Elevated Temperature

    Science.gov (United States)

    2016-09-01

    suitability of this composite for use in aerospace components designed to contain high-temperature environments, mechanical tests were performed under... contain high-temperature environments, mechanical tests were performed under temperature conditions simulating the actual operating conditions. In all... MECHANICAL PROPERTIES AND FATIGUE BEHAVIOR OF UNITIZED COMPOSITE AIRFRAME STRUCTURES AT ELEVATED

  14. 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…

  15. CFD Analysis of the SBXC Glider Airframe

    Science.gov (United States)

    2016-06-01

    greater than 15 m/s. 14. SUBJECT TERMS finite element method, computational fluid dynamics, Y Plus , mesh element quality, aerodynamic data, fluid...domain, Solidworks/ANSYS, 3D modeling and simulation 15. NUMBER OF PAGES 103 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT Unclassified...reduce manufacturing costs and expedite airframe development. The SBXC airplane is currently utilized as the flight platform in the Naval Postgraduate

  16. Airframe Noise from a Hybrid Wing Body Aircraft Configuration

    Science.gov (United States)

    Hutcheson, Florence V.; Spalt, Taylor B.; Brooks, Thomas F.; Plassman, Gerald E.

    2016-01-01

    A high fidelity aeroacoustic test was conducted in the NASA Langley 14- by 22-Foot Subsonic Tunnel to establish a detailed database of component noise for a 5.8% scale HWB aircraft configuration. The model has a modular design, which includes a drooped and a stowed wing leading edge, deflectable elevons, twin verticals, and a landing gear system with geometrically scaled wheel-wells. The model is mounted inverted in the test section and noise measurements are acquired at different streamwise stations from an overhead microphone phased array and from overhead and sideline microphones. Noise source distribution maps and component noise spectra are presented for airframe configurations representing two different approach flight conditions. Array measurements performed along the aircraft flyover line show the main landing gear to be the dominant contributor to the total airframe noise, followed by the nose gear, the inboard side-edges of the LE droop, the wing tip/LE droop outboard side-edges, and the side-edges of deployed elevons. Velocity dependence and flyover directivity are presented for the main noise components. Decorrelation effects from turbulence scattering on spectral levels measured with the microphone phased array are discussed. Finally, noise directivity maps obtained from the overhead and sideline microphone measurements for the landing gear system are provided for a broad range of observer locations.

  17. Airframe Noise Prediction by Acoustic Analogy: Revisited

    Science.gov (United States)

    Farassat, F.; Casper, Jay H.; Tinetti, A.; Dunn, M. H.

    2006-01-01

    The present work follows a recent survey of airframe noise prediction methodologies. In that survey, Lighthill s acoustic analogy was identified as the most prominent analytical basis for current approaches to airframe noise research. Within this approach, a problem is typically modeled with the Ffowcs Williams and Hawkings (FW-H) equation, for which a geometry-independent solution is obtained by means of the use of the free-space Green function (FSGF). Nonetheless, the aeroacoustic literature would suggest some interest in the use of tailored or exact Green s function (EGF) for aerodynamic noise problems involving solid boundaries, in particular, for trailing edge (TE) noise. A study of possible applications of EGF for prediction of broadband noise from turbulent flow over an airfoil surface and the TE is, therefore, the primary topic of the present work. Typically, the applications of EGF in the literature have been limited to TE noise prediction at low Mach numbers assuming that the normal derivative of the pressure vanishes on the airfoil surface. To extend the application of EGF to higher Mach numbers, the uniqueness of the solution of the wave equation when either the Dirichlet or the Neumann boundary condition (BC) is specified on a deformable surface in motion. The solution of Lighthill s equation with either the Dirichlet or the Neumann BC is given for such a surface using EGFs. These solutions involve both surface and volume integrals just like the solution of FW-H equation using FSGF. Insight drawn from this analysis is evoked to discuss the potential application of EGF to broadband noise prediction. It appears that the use of a EGF offers distinct advantages for predicting TE noise of an airfoil when the normal pressure gradient vanishes on the airfoil surface. It is argued that such an approach may also apply to an airfoil in motion. However, for the prediction of broadband noise not directly associated with a trailing edge, the use of EGF does not

  18. Overview of the Transport Rotorcraft Airframe Crash Testbed (TRACT) Full Scale Crash Tests

    Science.gov (United States)

    Annett, Martin; Littell, Justin

    2015-01-01

    The Transport Rotorcraft Airframe Crash Testbed (TRACT) full-scale tests were performed at NASA Langley Research Center's Landing and Impact Research Facility in 2013 and 2014. Two CH-46E airframes were impacted at 33-ft/s forward and 25-ft/s vertical combined velocities onto soft soil, which represents a severe, but potentially survivable impact scenario. TRACT 1 provided a baseline set of responses, while TRACT 2 included retrofits with composite subfloors and other crash system improvements based on TRACT 1. For TRACT 2, a total of 18 unique experiments were conducted to evaluate Anthropomorphic Test Devices (ATD) responses, seat and restraint performance, cargo restraint effectiveness, patient litter behavior, and activation of emergency locator transmitters and crash sensors. Combinations of Hybrid II, Hybrid III, and ES-2 ATDs were placed in forward and side facing seats and occupant results were compared against injury criteria. The structural response of the airframe was assessed based on accelerometers located throughout the airframe and using three-dimensional photogrammetric techniques. Analysis of the photogrammetric data indicated regions of maximum deflection and permanent deformation. The response of TRACT 2 was noticeably different in the horizontal direction due to changes in the cabin configuration and soil surface, with higher acceleration and damage occurring in the cabin. Loads from ATDs in energy absorbing seats and restraints were within injury limits. Severe injury was likely for ATDs in forward facing passenger seats.

  19. Evaluation of the First Transport Rotorcraft Airframe Crash Testbed (TRACT 1) Full-Scale Crash Test

    Science.gov (United States)

    Annett, Martin S.; Littell, Justin D.; Jackson, Karen E.; Bark, Lindley W.; DeWeese, Rick L.; McEntire, B. Joseph

    2014-01-01

    In 2012, the NASA Rotary Wing Crashworthiness Program initiated the Transport Rotorcraft Airframe Crash Testbed (TRACT) research program by obtaining two CH-46E helicopters from the Navy CH-46E Program Office (PMA-226) at the Navy Flight Readiness Center in Cherry Point, North Carolina. Full-scale crash tests were planned to assess dynamic responses of transport-category rotorcraft under combined horizontal and vertical impact loading. The first crash test (TRACT 1) was performed at NASA Langley Research Center's Landing and Impact Research Facility (LandIR), which enables the study of critical interactions between the airframe, seat, and occupant during a controlled crash environment. The CH-46E fuselage is categorized as a medium-lift rotorcraft with fuselage dimensions comparable to a regional jet or business jet. The first TRACT test (TRACT 1) was conducted in August 2013. The primary objectives for TRACT 1 were to: (1) assess improvements to occupant loads and displacement with the use of crashworthy features such as pre-tensioning active restraints and energy absorbing seats, (2) develop novel techniques for photogrammetric data acquisition to measure occupant and airframe kinematics, and (3) provide baseline data for future comparison with a retrofitted airframe configuration. Crash test conditions for TRACT 1 were 33-ft/s forward and 25-ft/s vertical combined velocity onto soft soil, which represent a severe, but potentially survivable impact scenario. The extraordinary value of the TRACT 1 test was reflected by the breadth of meaningful experiments. A total of 8 unique experiments were conducted to evaluate ATD responses, seat and restraint performance, cargo restraint effectiveness, patient litter behavior, and photogrammetric techniques. A combination of Hybrid II, Hybrid III, and ES-2 Anthropomorphic Test Devices (ATDs) were placed in forward and side facing seats and occupant results were compared against injury criteria. Loads from ATDs in energy

  20. Comparative design of structures concepts and methodologies

    CERN Document Server

    Lin, Shaopei

    2016-01-01

    This book presents comparative design as an approach to the conceptual design of structures. Primarily focusing on reasonable structural performance, sustainable development and architectural aesthetics, it features detailed studies of structural performance through the composition and de-composition of these elements for a variety of structures, such as high-rise buildings, long-span crossings and spatial structures. The latter part of the book addresses the theoretical basis and practical implementation of knowledge engineering in structural design, and a case-based fuzzy reasoning method is introduced to illustrate the concept and method of intelligent design. The book is intended for civil engineers, structural designers and architects, as well as senior undergraduate and graduate students in civil engineering and architecture. Shaopei Lin and Zhen Huang are both Professors at the Department of Civil Engineering, Shanghai Jiao Tong University, China.

  1. Experiences at Langley Research Center in the application of optimization techniques to helicopter airframes for vibration reduction

    Science.gov (United States)

    Murthy, T. Sreekanta; Kvaternik, Raymond G.

    1991-01-01

    A NASA/industry rotorcraft structural dynamics program known as Design Analysis Methods for VIBrationS (DAMVIBS) was initiated at Langley Research Center in 1984 with the objective of establishing the technology base needed by the industry for developing an advanced finite-element-based vibrations design analysis capability for airframe structures. As a part of the in-house activities contributing to that program, a study was undertaken to investigate the use of formal, nonlinear programming-based, numerical optimization techniques for airframe vibrations design work. Considerable progress has been made in connection with that study since its inception in 1985. This paper presents a unified summary of the experiences and results of that study. The formulation and solution of airframe optimization problems are discussed. Particular attention is given to describing the implementation of a new computational procedure based on MSC/NASTRAN and CONstrained function MINimization (CONMIN) in a computer program system called DYNOPT for the optimization of airframes subject to strength, frequency, dynamic response, and fatigue constraints. The results from the application of the DYNOPT program to the Bell AH-1G helicopter are presented and discussed.

  2. Airframe and Powerplant Mechanics Certification Guide. Revised 1971.

    Science.gov (United States)

    Federal Aviation Administration (DOT), Washington, DC. Flight Standards Service.

    The guide was prepared to provide information to prospective airframe and powerplant mechanics and other persons interested in the certification of mechanics. The requirements for a mechanic certificate are concerned with age, language ability, experience, knowledge, and skill. The sections of the guide explain the procedure for either…

  3. Airframe technology for aircraft energy efficiency. [economic factors

    Science.gov (United States)

    James, R. L., Jr.; Maddalon, D. V.

    1984-01-01

    The economic factors that resulted in the implementation of the aircraft energy efficiency program (ACEE) are reviewed and airframe technology elements including content, progress, applications, and future direction are discussed. The program includes the development of laminar flow systems, advanced aerodynamics, active controls, and composite structures.

  4. Computational Structures Technology for Airframes and Propulsion Systems

    Science.gov (United States)

    Noor, Ahmed K. (Compiler); Housner, Jerrold M. (Compiler); Starnes, James H., Jr. (Compiler); Hopkins, Dale A. (Compiler); Chamis, Christos C. (Compiler)

    1992-01-01

    This conference publication contains the presentations and discussions from the joint University of Virginia (UVA)/NASA Workshops. The presentations included NASA Headquarters perspectives on High Speed Civil Transport (HSCT), goals and objectives of the UVA Center for Computational Structures Technology (CST), NASA and Air Force CST activities, CST activities for airframes and propulsion systems in industry, and CST activities at Sandia National Laboratory.

  5. Evaluation of finite element formulations for transient conduction forced-convection analysis. [of heat transfer for active cooling of hypersonic airframe and engine structures

    Science.gov (United States)

    Thornton, E. A.; Wieting, A. R.

    1979-01-01

    Conventional versus upwind convective finite elements, and lumped versus consistent formulations for practical conduction/forced convection analysis are evaluated on the basis of numerical studies, with finite element and finite difference lumped-parameter temperatures compared to closed-form analytical solutions for convection problems. Attention is given to two practical combined conduction and forced convection applications, stressing that the finite element method, showing superior accuracy, is competitive with the finite difference lumped-parameter method. Also considered are the computational time savings offered by the zero capacitance nodes procedure and comparative finite element and finite difference lumped-parameter computer times. The present study has reference to the design of actively cooled engine and airframe structures for hypersonic flight.

  6. Avionics and airframe options: current usage and future plans.

    Science.gov (United States)

    Mayfield, T; Cady, G

    1994-01-01

    The 1994 Avionics and Airframe Survey was sent to 178 chief or lead pilots of helicopter emergency medical services (HEMS) programs in October 1993, and 100 (56%) were returned. Sixty-four programs (64%) reported that they operate one helicopter exclusively for EMS, 24 (24%) operate two, and 12 (12%) reported using three or more aircraft. Interestingly, the reported percentage of programs with two or more exclusive helicopters continues to rise, increasing by 5.6% to 36%.

  7. Construction and materials of airframe resisting severer fleight environment

    Energy Technology Data Exchange (ETDEWEB)

    Sanbongi, Shigeo

    1988-07-01

    It is unavoidable for any spaceplane to encounter mechanically and thermally severe conditions regardless of the type when taking off and asecending or reentering the atmosphere. The nose part and other parts of smaller curvature are heated to about 1,500/sup 0/C by the friction between air and the airframe. The minimum temperature in the airframe is -253/sup 0/C in the liquid hydrogen tank and it is required for the construction to resist this larger temperature difference and severe mechanical outside load. For these reasons, the airframe side wall is constructed by thermal protection system(PTS), main construction material and insulating material; and suitable materials and constructions must be selected to respective parts. In addition to using different heat resistant materials for PTS, an active mean to cool heated parts with a coolant can be thought. There are much technical accumulations in the USA, and there is large technological gap between Japan and the USA but Japan may display the power with advanced materials. (9 figs, 6 refs)

  8. Collaboration between Industrial Designers and Design Engineers - Comparing the Understanding of Design Intent.

    Science.gov (United States)

    Laursen, Esben Skov; Møller, Louise

    2015-01-01

    This paper describes a case study comparing the understanding of design intent between industrial designers and design engineers. The study is based on the hypothesis that it is not all aspects of the design intent that are equally difficult to share between industrial designers and design engineers in the product development process. The study builds on five semi-structured interviews, where two industrial designers and three design engineers were interviewed about different aspects of the design intent. Based on our results, there seem to be indications that the more complex and abstract elements of industrial design knowledge such as the meaning, semantics, values, emotions and social aspects of the product are less shared by the design engineers. Moreover, the results also indicate that the different aspects of the design intent are perceived separately, rather than as part of a whole by the design engineers. The connection between the different aspects of the design intent is not shared between the industrial designer and design engineer making the shared knowledge less meaningful to the design engineers. The results of this study cannot be claimed to be conclusive due to the limited empirical material. Further investigation and analytically richer data are required in order to verify and broaden the findings. More case studies have therefore been planned in order to understand the area better.

  9. Cirrus Airframe Parachute System and Odds of a Fatal Accident in Cirrus Aircraft Crashes.

    Science.gov (United States)

    Alaziz, Mustafa; Stolfi, Adrienne; Olson, Dean M

    2017-06-01

    General aviation (GA) accidents have continued to demonstrate high fatality rates. Recently, ballistic parachute recovery systems (BPRS) have been introduced as a safety feature in some GA aircraft. This study evaluates the effectiveness and associated factors of the Cirrus Airframe Parachute System (CAPS) at reducing the odds of a fatal accident in Cirrus aircraft crashes. Publicly available Cirrus aircraft crash reports were obtained from the National Transportation Safety Board (NTSB) database for the period of January 1, 2001-December 31, 2016. Accident metrics were evaluated through univariate and multivariate analyses regarding odds of a fatal accident and use of the parachute system. Included in the study were 268 accidents. For CAPS nondeployed accidents, 82 of 211 (38.9%) were fatal as compared to 8 of 57 (14.0%) for CAPS deployed accidents. After controlling for all other factors, the adjusted odds ratio for a fatal accident when CAPS was not deployed was 13.1. The substantial increased odds of a fatal accident when CAPS was not deployed demonstrated the effectiveness of CAPS at providing protection of occupants during an accident. Injuries were shifted from fatal to serious or minor with the use of CAPS and postcrash fires were significantly reduced. These results suggest that BPRS could play a significant role in the next major advance in improving GA accident survival.Alaziz M, Stolfi A, Olson DM. Cirrus Airframe Parachute System and odds of a fatal accident in Cirrus aircraft crashes. Aerosp Med Hum Perform. 2017; 88(6):556-564.

  10. FAA/NASA International Symposium on Advanced Structural Integrity Methods for Airframe Durability and Damage Tolerance

    Science.gov (United States)

    Harris, Charles E. (Editor)

    1994-01-01

    International technical experts in durability and damage tolerance of metallic airframe structures were assembled to present and discuss recent research findings and the development of advanced design and analysis methods, structural concepts, and advanced materials. The symposium focused on the dissemination of new knowledge and the peer-review of progress on the development of advanced methodologies. Papers were presented on: structural concepts for enhanced durability, damage tolerance, and maintainability; new metallic alloys and processing technology; fatigue crack initiation and small crack effects; fatigue crack growth models; fracture mechanics failure, criteria for ductile materials; structural mechanics methodology for residual strength and life prediction; development of flight load spectra for design and testing; and advanced approaches to resist corrosion and environmentally assisted fatigue.

  11. Comparing laser printing and barcode scanning designs

    Science.gov (United States)

    MacArthur, Thomas D.

    1991-02-01

    A comparison of requirements and designs for barcode and non-impact printer scanners reveals similarities and differences that may be useful in leading to new solutions for barcode scanner problems. The non-impact printer scanner has been in volume production for over 10 years successfully achieving low cost high performance and high quality targets. Where requirements are found to overlap solutions already implemented and proven for printer applications may fmd further application in bar code scanners. Typical technologies used for printing include flying spot scanners liquid crystal shutters scophony scanners and LED arrays. Of primary concern in measuring figure of merit are such critical parameters as cost lifetime reliability conformance to regulatory standards environmental ruggedness power consumption compactness insensitivity to orientation acoustic noise produced modularity spot size depth of field exposure level and uniformity data rate scan length and uniformity and many more. A comparison of printing technologies their capabilities and their limitations with those used in barcode scanners may reveal common problems where we can take advantage of work already completed in similar application where requirements are found to overlap.

  12. Development, documentation and correlation of a NASTRAN vibration model of the AH-1G helicopter airframe

    Science.gov (United States)

    Cronkhite, J. D.

    1976-01-01

    NASTRAN was evaluated for vibration analysis of the helicopter airframe. The first effort involved development of a NASTRAN model of the AH-1G helicopter airframe and comprehensive documentation of the model. The next effort was to assess the validity of the NASTRAN model by comparisons with static and vibration tests.

  13. Fabrication and development of several heat pipe honeycomb sandwich panel concepts. [airframe integrated scramjet engine

    Science.gov (United States)

    Tanzer, H. J.

    1982-01-01

    The feasibility of fabricating and processing liquid metal heat pipes in a low mass honeycomb sandwich panel configuration for application on the NASA Langley airframe-integrated Scramjet engine was investigated. A variety of honeycomb panel facesheet and core-ribbon wick concepts was evaluated within constraints dictated by existing manufacturing technology and equipment. The chosen design consists of an all-stainless steel structure, sintered screen facesheets, and two types of core-ribbon; a diffusion bonded wire mesh and a foil-screen composite. Cleaning, fluid charging, processing, and process port sealing techniques were established. The liquid metals potassium, sodium and cesium were used as working fluids. Eleven honeycomb panels 15.24 cm X 15.24 cm X 2.94 cm were delivered to NASA Langley for extensive performance testing and evaluation; nine panels were processed as heat pipes, and two panels were left unprocessed.

  14. Integrating CFD, CAA, and Experiments Towards Benchmark Datasets for Airframe Noise Problems

    Science.gov (United States)

    Choudhari, Meelan M.; Yamamoto, Kazuomi

    2012-01-01

    Airframe noise corresponds to the acoustic radiation due to turbulent flow in the vicinity of airframe components such as high-lift devices and landing gears. The combination of geometric complexity, high Reynolds number turbulence, multiple regions of separation, and a strong coupling with adjacent physical components makes the problem of airframe noise highly challenging. Since 2010, the American Institute of Aeronautics and Astronautics has organized an ongoing series of workshops devoted to Benchmark Problems for Airframe Noise Computations (BANC). The BANC workshops are aimed at enabling a systematic progress in the understanding and high-fidelity predictions of airframe noise via collaborative investigations that integrate state of the art computational fluid dynamics, computational aeroacoustics, and in depth, holistic, and multifacility measurements targeting a selected set of canonical yet realistic configurations. This paper provides a brief summary of the BANC effort, including its technical objectives, strategy, and selective outcomes thus far.

  15. Design Of High Performance CMOS Dynamic Latch Comparator

    Directory of Open Access Journals (Sweden)

    G.Saroja

    2016-10-01

    Full Text Available High performance analog to digital converters (ADC, memory sense amplifiers, and Radio Frequency identification applications, data receivers with less area and power efficient designs has attracted a broad range of dynamic comparators. This paper presents an ameliorate design for a dynamic latch based comparator in attaining high performance. The comparators accuracyis mainly defined by two factors they are speed and power consumption. The latch based comparator has two different stages encompassing of a dynamic differential input gain stage and an output latch.The output node in the differential gain stage of proposed comparator requires lesser time to regain higher charge potential. The proposed comparator hasbeen designed and simulated using 130nm CMOS 1P2M technology by using mentor graphics tools with a supply voltage of 1V. Proposed dynamic latch comparator iscompared with existing conventional dynamic latch comparator and with other comparators and the results are discussed in detail.

  16. Development of a SMA-Based, Slat-Gap Filler for Airframe Noise Reduction

    Science.gov (United States)

    Turner, Travis L.; Long, David L.

    2015-01-01

    Noise produced by unsteady flow around aircraft structures, termed airframe noise, is an important source of aircraft noise during the approach and landing phases of flight. Conventional leading-edge-slat devices for high lift on typical transport aircraft are a prominent source of airframe noise. Many concepts for slat noise reduction have been investigated. Slat-cove fillers have emerged as an attractive solution, but they maintain the gap flow, leaving some noise production mechanisms unabated, and thus represent a nonoptimal solution. Drooped-leading-edge (DLE) concepts have been proposed as "optimal" because the gap flow is eliminated. The deployed leading edge device is not distinct and separate from the main wing in DLE concepts and the high-lift performance suffers at high angles of attack (alpha) as a consequence. Elusive high-alpha performance and excessive weight penalty have stymied DLE development. The fact that high-lift performance of DLE systems is only affected at high alpha suggests another concept that simultaneously achieves the high-lift of the baseline airfoil and the noise reduction of DLE concepts. The concept involves utilizing a conventional leading-edge slat device and a deformable structure that is deployed from the leading edge of the main wing and closes the gap between the slat and main wing, termed a slat-gap filler (SGF). The deployable structure consists of a portion of the skin of the main wing and it is driven in conjunction with the slat during deployment and retraction. Benchtop models have been developed to assess the feasibility and to study important parameters. Computational models have assisted in the bench-top model design and provided valuable insight in the parameter space as well as the feasibility.

  17. Novel Parity-Preserving Designs of Reversible 4-Bit Comparator

    Science.gov (United States)

    Qi, Xue-mei; Chen, Fu-long; Wang, Hong-tao; Sun, Yun-xiang; Guo, Liang-min

    2014-04-01

    Reversible logic has attracted much attention in recent years especially when the calculation with minimum energy consumption is considered. This paper presents two novel approaches for designing reversible 4-bit comparator based on parity-preserving gates, which can detect any fault that affects no more than a single logic signal. In order to construct the comparator, three variable EX-OR gate (TVG), comparator gate (CPG), four variable EX-OR gate block (FVGB) and comparator gate block (CPGB) are designed, and they are parity-preserving and reversible. Their quantum equivalent implementations are also proposed. The design of two comparator circuits is completed by using existing reversible gates and the above new reversible circuits. All these comparators have been modeled and verified in Verilog hardware description language (Verilog HDL). The Quartus II simulation results indicate that their circuits' logic structures are correct. The comparative results are presented in terms of quantum cost, delay and garbage outputs.

  18. Novel Low Power Comparator Design using Reversible Logic Gates

    Directory of Open Access Journals (Sweden)

    Nagamani A N

    2011-09-01

    Full Text Available Reversible logic has received great attention in the recent years due to its ability to reduce the power dissipation which is the main requirement in low power digital design. It has wide applications inadvanced computing, low power CMOS design, Optical information processing, DNA computing, bio information, quantum computation and nanotechnology. This paper presents a novel design of reversiblecomparator using the existing reversible gates and proposed new Reversible BJN gate. All the comparators have been modeled and verified using VHDL and ModelSim. A comparative result is presented in terms of number of gates, number of garbage outputs, number of constant inputs and Quantum cost.

  19. Designs and Technology Requirements for Civil Heavy Lift Rotorcraft

    Science.gov (United States)

    Johnson, Wayne; Yamauchi, Gloria K.; Watts, Michael E.

    2006-01-01

    The NASA Heavy Lift Rotorcraft Systems Investigation examined in depth several rotorcraft configurations for large civil transport, designed to meet the technology goals of the NASA Vehicle Systems Program. The investigation identified the Large Civil Tiltrotor as the configuration with the best potential to meet the technology goals. The design presented was economically competitive, with the potential for substantial impact on the air transportation system. The keys to achieving a competitive aircraft were low drag airframe and low disk loading rotors; structural weight reduction, for both airframe and rotors; drive system weight reduction; improved engine efficiency; low maintenance design; and manufacturing cost comparable to fixed-wing aircraft. Risk reduction plans were developed to provide the strategic direction to support a heavy-lift rotorcraft development. The following high risk areas were identified for heavy lift rotorcraft: high torque, light weight drive system; high performance, structurally efficient rotor/wing system; low noise aircraft; and super-integrated vehicle management system.

  20. High Order Wavelet-Based Multiresolution Technology for Airframe Noise Prediction Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a novel, high-accuracy, high-fidelity, multiresolution (MRES), wavelet-based framework for efficient prediction of airframe noise sources and...

  1. High Order Wavelet-Based Multiresolution Technology for Airframe Noise Prediction Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An integrated framework is proposed for efficient prediction of rotorcraft and airframe noise. A novel wavelet-based multiresolution technique and high-order...

  2. Propulsion airframe integration session overview and review of Lewis PAI efforts

    Science.gov (United States)

    Batterton, Peter G.

    1992-01-01

    Propulsion/Airframe Integration (PAI) is a key issue for the High Speed Civil Transport. The aircraft performance, economics, and environmental acceptability can be adversely affected if the integration of the propulsion system and the airframe is not addressed properly or in a timely manner. Some of the goals are listed in this figure. In particular, these goals are highly influenced by how successfully the propulsion system and airframe are integrated. These goals were grouped by the 'Aero' and 'Propulsion' categories to suggest which group of technologists will likely be addressing them. In terms of the NASA High Speed Research Program, the ultimate objective for propulsion/airframe integration is to demonstrate the technologies for achievement of these goals on a 'single' integrated configuration.

  3. The incident user design in comparative effectiveness research.

    Science.gov (United States)

    Johnson, Eric S; Bartman, Barbara A; Briesacher, Becky A; Fleming, Neil S; Gerhard, Tobias; Kornegay, Cynthia J; Nourjah, Parivash; Sauer, Brian; Schumock, Glen T; Sedrakyan, Art; Stürmer, Til; West, Suzanne L; Schneeweiss, Sebastian

    2013-01-01

    Comparative effectiveness research includes cohort studies and registries of interventions. When investigators design such studies, how important is it to follow patients from the day they initiated treatment with the study interventions? Our article considers this question and related issues to start a dialogue on the value of the incident user design in comparative effectiveness research. By incident user design, we mean a study that sets the cohort's inception date according to patients' new use of an intervention. In contrast, most epidemiologic studies enroll patients who were currently or recently using an intervention when follow-up began. We take the incident user design as a reasonable default strategy because it reduces biases that can impact non-randomized studies, especially when investigators use healthcare databases. We review case studies where investigators have explored the consequences of designing a cohort study by restricting to incident users, but most of the discussion has been informed by expert opinion, not by systematic evidence.

  4. Plan, execute, and discuss vibration measurements and correlations to evaluate a NASTRAN finite element model of the AH-64 helicopter airframe

    Science.gov (United States)

    Ferg, D.; Foote, L.; Korkosz, G.; Straub, F.; Toossi, M.; Weisenburger, R.

    1990-01-01

    A ground vibration test was performed on the AH-64 (Apache) helicopter to determine the frequency response of the airframe. The structure was excited at both the main and tail rotor hubs, separately, and response measurements were taken at 102 locations throughout the fuselage structure. Frequency responses were compared and correlated with results from a NASTRAN finite element model of AH-64. In addition, natural frequencies and mode shapes were estimated from the frequency response data and were correlated with analytical results.

  5. Towards an Airframe Noise Prediction Methodology: Survey of Current Approaches

    Science.gov (United States)

    Farassat, Fereidoun; Casper, Jay H.

    2006-01-01

    In this paper, we present a critical survey of the current airframe noise (AFN) prediction methodologies. Four methodologies are recognized. These are the fully analytic method, CFD combined with the acoustic analogy, the semi-empirical method and fully numerical method. It is argued that for the immediate need of the aircraft industry, the semi-empirical method based on recent high quality acoustic database is the best available method. The method based on CFD and the Ffowcs William- Hawkings (FW-H) equation with penetrable data surface (FW-Hpds ) has advanced considerably and much experience has been gained in its use. However, more research is needed in the near future particularly in the area of turbulence simulation. The fully numerical method will take longer to reach maturity. Based on the current trends, it is predicted that this method will eventually develop into the method of choice. Both the turbulence simulation and propagation methods need to develop more for this method to become useful. Nonetheless, the authors propose that the method based on a combination of numerical and analytical techniques, e.g., CFD combined with FW-H equation, should also be worked on. In this effort, the current symbolic algebra software will allow more analytical approaches to be incorporated into AFN prediction methods.

  6. Comparative study of codes for the seismic design of structures

    Directory of Open Access Journals (Sweden)

    S. H. C. Santos

    Full Text Available A general evaluation of some points of the South American seismic codes is presented herein, comparing them among themselves and with the American Standard ASCE/SEI 7/10 and with the European Standard Eurocode 8. The study is focused in design criteria for buildings. The Western border of South America is one of the most seismically active regions of the World. It corresponds to the confluence of the South American and Nazca plates. This region corresponds roughly to the vicinity of the Andes Mountains. This seismicity diminishes in the direction of the comparatively seismically quieter Eastern South American areas. The South American countries located in its Western Border possess standards for seismic design since some decades ago, being the Brazilian Standard for seismic design only recently published. This study is focused in some critical topics: definition of the recurrence periods for establishing the seismic input; definition of the seismic zonation and design ground motion values; definition of the shape of the design response spectra; consideration of soil amplification, soil liquefaction and soil-structure interaction; classification of the structures in different importance levels; definition of the seismic force-resisting systems and respective response modification coefficients; consideration of structural irregularities and definition of the allowable procedures for the seismic analyses. A simple building structure is analyzed considering the criteria of the several standards and obtained results are compared.

  7. Systems design and comparative analysis of large antenna concepts

    Science.gov (United States)

    Garrett, L. B.; Ferebee, M. J., Jr.

    1983-01-01

    Conceptual designs are evaluated and comparative analyses conducted for several large antenna spacecraft for Land Mobile Satellite System (LMSS) communications missions. Structural configurations include trusses, hoop and column and radial rib. The study was conducted using the Interactive Design and Evaluation of Advanced Spacecraft (IDEAS) system. The current capabilities, development status, and near-term plans for the IDEAS system are reviewed. Overall capabilities are highlighted. IDEAS is an integrated system of computer-aided design and analysis software used to rapidly evaluate system concepts and technology needs for future advanced spacecraft such as large antennas, platforms, and space stations. The system was developed at Langley to meet a need for rapid, cost-effective, labor-saving approaches to the design and analysis of numerous missions and total spacecraft system options under consideration. IDEAS consists of about 40 technical modules efficient executive, data-base and file management software, and interactive graphics display capabilities.

  8. Design Of A 65 Nm Cmos Comparator With Hysteresis

    Directory of Open Access Journals (Sweden)

    Aleksandr Vasjanov

    2014-05-01

    Full Text Available The comparator can be described as one of the basic building blocks in electronics. It is implemented both as a discrete device and as a constituent of a complex circuit. In both cases, the circuits usually operate in conditions, where useful and unwanted (noise signals are present at the same time. In order to maintain the validity of output data, a hysteresis parameter is introduced to the comparator’s circuit. This article presents the results of a CMOS comparator with hysteresis design – the schematic, topology and simulation results are analyzed. The designed comparator is implemented in a zero voltage offset compensation circuit ADC in a multi-standard transceiver IC.

  9. Toward Establishing a Realistic Benchmark for Airframe Noise Research: Issues and Challenges

    Science.gov (United States)

    Khorrami, Mehdi R.

    2010-01-01

    The availability of realistic benchmark configurations is essential to enable the validation of current Computational Aeroacoustic (CAA) methodologies and to further the development of new ideas and concepts that will foster the technologies of the next generation of CAA tools. The selection of a real-world configuration, the subsequent design and fabrication of an appropriate model for testing, and the acquisition of the necessarily comprehensive aeroacoustic data base are critical steps that demand great care and attention. In this paper, a brief account of the nose landing-gear configuration, being proposed jointly by NASA and the Gulfstream Aerospace Company as an airframe noise benchmark, is provided. The underlying thought processes and the resulting building block steps that were taken during the development of this benchmark case are given. Resolution of critical, yet conflicting issues is discussed - the desire to maintain geometric fidelity versus model modifications required to accommodate instrumentation; balancing model scale size versus Reynolds number effects; and time, cost, and facility availability versus important parameters like surface finish and installation effects. The decisions taken during the experimental phase of a study can significantly affect the ability of a CAA calculation to reproduce the prevalent flow conditions and associated measurements. For the nose landing gear, the most critical of such issues are highlighted and the compromises made to resolve them are discussed. The results of these compromises will be summarized by examining the positive attributes and shortcomings of this particular benchmark case.

  10. Towards Full Aircraft Airframe Noise Prediction: Lattice Boltzmann Simulations

    Science.gov (United States)

    Khorrami, Mehdi R.; Fares, Ehab; Casalino, Damiano

    2014-01-01

    Computational results for an 18%-scale, semi-span Gulfstream aircraft model are presented. Exa Corporation's lattice Boltzmann PowerFLOW(trademark) solver was used to perform time-dependent simulations of the flow field associated with this high-fidelity aircraft model. The simulations were obtained for free-air at a Mach number of 0.2 with the flap deflected at 39 deg (landing configuration). We focused on accurately predicting the prominent noise sources at the flap tips and main landing gear for the two baseline configurations, namely, landing flap setting without and with gear deployed. Capitalizing on the inherently transient nature of the lattice Boltzmann formulation, the complex time-dependent flow features associated with the flap were resolved very accurately and efficiently. To properly simulate the noise sources over a broad frequency range, the tailored grid was very dense near the flap inboard and outboard tips. Extensive comparison of the computed time-averaged and unsteady surface pressures with wind tunnel measurements showed excellent agreement for the global aerodynamic characteristics and the local flow field at the flap inboard and outboard tips and the main landing gear. In particular, the computed fluctuating surface pressure field for the flap agreed well with the measurements in both amplitude and frequency content, indicating that the prominent airframe noise sources at the tips were captured successfully. Gear-flap interaction effects were remarkably well predicted and were shown to affect only the inboard flap tip, altering the steady and unsteady pressure fields in that region. The simulated farfield noise spectra for both baseline configurations, obtained using a Ffowcs-Williams and Hawkings acoustic analogy approach, were shown to be in close agreement with measured values.

  11. Comparative Study of Antenna Designs for RF Energy Harvesting

    Directory of Open Access Journals (Sweden)

    Sika Shrestha

    2013-01-01

    Full Text Available In the last few years, several antenna designs of rectenna that meet various objectives have been proposed for use in RF energy harvesting. Among various antennas, microstrip patch antennas are widely used because of their low profile, light weight, and planar structure. Conventional patch antennas are rectangular or circular in shape, but variations in their basic design are made for different purposes. This paper begins with an explanation and discussion of different designs, put forward with an aim of miniaturization, harmonic rejection, and reconfigurability. Finally, microstrip patch structured rectennas are evaluated and compared with an emphasis on the various methods adopted to obtain a compact rectenna, harmonic rejection functionality, and frequency and polarization selectivity.

  12. Comparing Simulated Emission from Molecular Clouds Using Experimental Design

    CERN Document Server

    Yeremi, Miayan; Offner, Stella; Loeppky, Jason; Rosolowsky, Erik

    2014-01-01

    We propose a new approach to comparing simulated observations that enables us to determine the significance of the underlying physical effects. We utilize the methodology of experimental design, a subfield of statistical analysis, to establish a framework for comparing simulated position-position-velocity data cubes to each other. We propose three similarity metrics based on methods described in the literature: principal component analysis, the spectral correlation function, and the Cramer multi-variate two sample similarity statistic. Using these metrics, we intercompare a suite of mock observational data of molecular clouds generated from magnetohydrodynamic simulations with varying physical conditions. Using this framework, we show that all three metrics are sensitive to changing Mach number and temperature in the simulation sets, but cannot detect changes in magnetic field strength and initial velocity spectrum. We highlight the shortcomings of one-factor-at-a-time designs commonly used in astrophysics an...

  13. Multidisciplinary design optimization of low-noise transport aircraft

    Science.gov (United States)

    Leifsson, Leifur Thor

    The objective of this research is to examine how to design low-noise transport aircraft using Multidisciplinary Design Optimization (MDO). The subject is approached by designing for low-noise both implicitly and explicitly. The explicit design approach involves optimizing an aircraft while explicitly constraining the noise level. An MDO framework capable of optimizing both a cantilever wing and a Strut-Braced-Wing (SBW) aircraft was developed. The objective is to design aircraft for low-airframe-noise at the approach conditions and quantify the change in weight and performance with respect to a traditionally designed aircraft. The results show that reducing airframe noise by reducing approach speed alone, will not provide significant noise reduction without a large performance and weight penalty. Therefore, more dramatic changes to the aircraft design are needed to achieve a significant airframe noise reduction. Another study showed that the trailing-edge flap can be eliminated, as well as all the noise associated with that device, without incurring a significant weight and performance penalty. Lastly, an airframe noise analysis showed that a SBW aircraft with short fuselage-mounted landing gear could have a similar or potentially a lower airframe noise level than a comparable cantilever wing aircraft. The implicit design approach involves selecting a configuration that supports a low-noise operation, and optimizing for performance. In this study a Blended-Wing-Body (BWB) transport aircraft, with a conventional and a distributed propulsion system, was optimized for minimum take-off gross weight. The effects of distributed propulsion were studied using an MDO framework previously developed at Virginia Tech. The results show that more than two thirds of the theoretical savings of distributed propulsion are required for the BWB designs with a distributed propulsion system to have comparable gross weight as those with a conventional propulsion system. Therefore

  14. Clustering of Parameter Sensitivities: Examples from a Helicopter Airframe Model Updating Exercise

    Directory of Open Access Journals (Sweden)

    H. Shahverdi

    2009-01-01

    Full Text Available The need for high fidelity models in the aerospace industry has become ever more important as increasingly stringent requirements on noise and vibration levels, reliability, maintenance costs etc. come into effect. In this paper, the results of a finite element model updating exercise on a Westland Lynx XZ649 helicopter are presented. For large and complex structures, such as a helicopter airframe, the finite element model represents the main tool for obtaining accurate models which could predict the sensitivities of responses to structural changes and optimisation of the vibration levels. In this study, the eigenvalue sensitivities with respect to Young's modulus and mass density are used in a detailed parameterisation of the structure. A new methodology is developed using an unsupervised learning technique based on similarity clustering of the columns of the sensitivity matrix. An assessment of model updating strategies is given and comparative results for the correction of vibration modes are discussed in detail. The role of the clustering technique in updating large-scale models is emphasised.

  15. Optimization Approaches for Designing a Novel 4-Bit Reversible Comparator

    Science.gov (United States)

    Zhou, Ri-gui; Zhang, Man-qun; Wu, Qian; Li, Yan-cheng

    2013-02-01

    Reversible logic is a new rapidly developed research field in recent years, which has been receiving much attention for calculating with minimizing the energy consumption. This paper constructs a 4×4 new reversible gate called ZRQ gate to build quantum adder and subtraction. Meanwhile, a novel 1-bit reversible comparator by using the proposed ZRQC module on the basis of ZRQ gate is proposed as the minimum number of reversible gates and quantum costs. In addition, this paper presents a novel 4-bit reversible comparator based on the 1-bit reversible comparator. One of the vital important for optimizing reversible logic is to design reversible logic circuits with the minimum number of parameters. The proposed reversible comparators in this paper can obtain superiority in terms of the number of reversible gates, input constants, garbage outputs, unit delays and quantum costs compared with the existed circuits. Finally, MATLAB simulation software is used to test and verify the correctness of the proposed 4-bit reversible comparator.

  16. Comparing simulated emission from molecular clouds using experimental design

    Energy Technology Data Exchange (ETDEWEB)

    Yeremi, Miayan; Flynn, Mallory; Loeppky, Jason; Rosolowsky, Erik [University of British Columbia, Okanagan Campus, Departments of Physics and Statistics, 3333 University Way, Kelowna BC V1V 1V7 (Canada); Offner, Stella [Yale University Astronomy Department, 260 Whitney Avenue, New Haven, CT 06511 (United States)

    2014-03-10

    We propose a new approach to comparing simulated observations that enables us to determine the significance of the underlying physical effects. We utilize the methodology of experimental design, a subfield of statistical analysis, to establish a framework for comparing simulated position-position-velocity data cubes to each other. We propose three similarity metrics based on methods described in the literature: principal component analysis, the spectral correlation function, and the Cramer multi-variate two-sample similarity statistic. Using these metrics, we intercompare a suite of mock observational data of molecular clouds generated from magnetohydrodynamic simulations with varying physical conditions. Using this framework, we show that all three metrics are sensitive to changing Mach number and temperature in the simulation sets, but cannot detect changes in magnetic field strength and initial velocity spectrum. We highlight the shortcomings of one-factor-at-a-time designs commonly used in astrophysics and propose fractional factorial designs as a means to rigorously examine the effects of changing physical properties while minimizing the investment of computational resources.

  17. Interferometry at the PTB Nanometer Comparator: design, status and development

    Science.gov (United States)

    Flügge, J.; Weichert, Ch.; Hu, H.; Köning, R.; Bosse, H.; Wiegmann, A.; Schulz, M.; Elster, C.; Geckeler, R. D.

    2008-10-01

    To minimize the measurement uncertainty of one dimensional length measurements on line scales, linear encoders and interferometers the PTB in cooperation with the Dr. Johannes Heidenhain GmbH had built up a new length comparator. The Nanometer Comparator [1,2] has already proven its performance during the measurements of incremental encoders and line scales with an expanded measurement uncertainty of below 5 nm [3,4,5]. Due to the introduction of double and multiple exposure in advanced lithography techniques the overlay and registration metrology requirements will drastically increase so that reference metrology tools need to be developed further to be able to follow the resulting decrease of the specifications. Therefore, the PTB further develops the new 1D vacuum comparator to add a measurement possibility for straightness and to reach a measurement accuracy in the sub nanometer range [6]. One key development will be the interferometric measurement of all six degrees of freedom of the measurement slide of the comparator. A new multi axis heterodyne interferometer electronics and optical interferometer designs minimizing nonlinearities by spatially separated beams are under development.

  18. A comparative design and tuning for conventional fuzzy control.

    Science.gov (United States)

    Li, H X

    1997-01-01

    A new methodology is introduced for designing and tuning the scaling gains of the conventional fuzzy logic controller (FLC) based on its well-tuned linear counterpart. The conventional FLC with a linear rule base is very similar to its linear counterpart. The linear three-term controller has proportional, integral and/or derivative gains. Similarly, the conventional fuzzy three-term controller also has fuzzy proportional, integral and/or derivative gains. The new concept "fuzzy transfer function" is invented to connect these fuzzy gains with the corresponding scaling gains. The comparative gain design is presented by using the gains of the well-tuned linear counterpart as the initial fuzzy gains of the conventional FLC. Furthermore, the relationship between the scaling gains and the performance can be deduced to produce the comparative tuning algorithm, which can tune the scaling gains to their optimum by less trial and error. The performance comparison in the simulation demonstrates the viability of the new methodology.

  19. Comparing linkage designs based on land facets to linkage designs based on focal species.

    Science.gov (United States)

    Brost, Brian M; Beier, Paul

    2012-01-01

    Least-cost modeling for focal species is the most widely used method for designing conservation corridors and linkages. However, these designs depend on today's land covers, which will be altered by climate change. We recently proposed an alternative approach based on land facets (recurring landscape units of relatively uniform topography and soils). The rationale is that corridors with high continuity of individual land facets will facilitate movement of species associated with each facet today and in the future. Conservation practitioners might like to know whether a linkage design based on land facets is likely to provide continuity of modeled breeding habitat for species needing connectivity today, and whether a linkage for focal species provides continuity and interspersion of land facets. To address these questions, we compared linkages designed for focal species and land facets in three landscapes in Arizona, USA. We used two variables to measure linkage utility, namely distances between patches of modeled breeding habitat for 5-16 focal species in each linkage, and resistance profiles for focal species and land facets between patches connected by the linkage. Compared to focal species designs, linkage designs based on land facets provided as much or more modeled habitat connectivity for 25 of 28 species-landscape combinations, failing only for the three species with the most narrowly distributed habitat. Compared to land facets designs, focal species linkages provided lower connectivity for about half the land facets in two landscapes. In areas where a focal species approach to linkage design is not possible, our results suggest that conservation practitioners may be able to implement a land facets approach with some confidence that the linkage design would serve most potential focal species. In areas where focal species designs are possible, we recommend using the land facet approach to complement, rather than replace, focal species approaches.

  20. Summary of the Tandem Cylinder Solutions from the Benchmark Problems for Airframe Noise Computations-I Workshop

    Science.gov (United States)

    Lockard, David P.

    2011-01-01

    Fifteen submissions in the tandem cylinders category of the First Workshop on Benchmark problems for Airframe Noise Computations are summarized. Although the geometry is relatively simple, the problem involves complex physics. Researchers employed various block-structured, overset, unstructured and embedded Cartesian grid techniques and considerable computational resources to simulate the flow. The solutions are compared against each other and experimental data from 2 facilities. Overall, the simulations captured the gross features of the flow, but resolving all the details which would be necessary to compute the noise remains challenging. In particular, how to best simulate the effects of the experimental transition strip, and the associated high Reynolds number effects, was unclear. Furthermore, capturing the spanwise variation proved difficult.

  1. Calibration of Airframe and Occupant Models for Two Full-Scale Rotorcraft Crash Tests

    Science.gov (United States)

    Annett, Martin S.; Horta, Lucas G.; Polanco, Michael A.

    2012-01-01

    Two full-scale crash tests of an MD-500 helicopter were conducted in 2009 and 2010 at NASA Langley's Landing and Impact Research Facility in support of NASA s Subsonic Rotary Wing Crashworthiness Project. The first crash test was conducted to evaluate the performance of an externally mounted composite deployable energy absorber under combined impact conditions. In the second crash test, the energy absorber was removed to establish baseline loads that are regarded as severe but survivable. Accelerations and kinematic data collected from the crash tests were compared to a system integrated finite element model of the test article. Results from 19 accelerometers placed throughout the airframe were compared to finite element model responses. The model developed for the purposes of predicting acceleration responses from the first crash test was inadequate when evaluating more severe conditions seen in the second crash test. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used to calibrate model results for the second full-scale crash test. This combination of heuristic and quantitative methods was used to identify modeling deficiencies, evaluate parameter importance, and propose required model changes. It is shown that the multi-dimensional calibration techniques presented here are particularly effective in identifying model adequacy. Acceleration results for the calibrated model were compared to test results and the original model results. There was a noticeable improvement in the pilot and co-pilot region, a slight improvement in the occupant model response, and an over-stiffening effect in the passenger region. This approach should be adopted early on, in combination with the building-block approaches that are customarily used, for model development and test planning guidance. Complete crash simulations with validated finite element models can be used

  2. COMPARATIVE DESIGN OF REGULAR STRUCTURED MODIFIED BOOTH MULTIPLIER

    Directory of Open Access Journals (Sweden)

    Ram RackshaTripathi

    2016-04-01

    Full Text Available Multiplication is a crucial function and plays a vital role for practically any DSP system. Several DSP algorithms require different types of multiplications, specifically modified booth multiplication algorithm. In this paper, a simple approach is proposed for generating last partial product row for reducing extra sign (negative bit bit to achieve more regular structure. As compared to the conventional multipliers these proposed modified Booth’s multipliers can achieve improved reduction in area 5.9%, power 3.2%, and delay 0.5% for 8 x 8 multipliers. We can also observe that achievable improvement for 16 x 16 multiplier in area, power, delay are 4.0%, 2.3%, 0.3% respectively. These multipliers are implemented using verilog HDL and synthesized by using synopsis design compiler with an Artisan TSMC 90nm Technology

  3. Comparative Study of Data Warehouse Design Approaches : A Survey

    Directory of Open Access Journals (Sweden)

    Rajni Jindal

    2012-03-01

    Full Text Available The process of developing a data warehouse starts with identifying and gathering requirements, designing the dimensional model followed by testing and maintenance. The design phase is the most important activity in the successful building of a data warehouse. In this paper, we surveyed and evaluated the literature related to the various data warehouse design approaches on the basis of design criteria and propose a generalized object oriented conceptual designframework based on UML that meets all types of user needs.

  4. Electrocoagulation in wastewater containing arsenic: Comparing different process designs

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Henrik K. [Departamento de Procesos Quimicos, Biotecnologicos y Ambientales, Universidad Tecnica Federico Santa Maria, Avenida Espana 1680, Valparaiso (Chile)]. E-mail: henrik.hansen@usm.cl; Nunez, Patricio [Departamento de Procesos Quimicos, Biotecnologicos y Ambientales, Universidad Tecnica Federico Santa Maria, Avenida Espana 1680, Valparaiso (Chile); Raboy, Deborah [Departamento de Procesos Quimicos, Biotecnologicos y Ambientales, Universidad Tecnica Federico Santa Maria, Avenida Espana 1680, Valparaiso (Chile); Schippacasse, Italo [Departamento de Procesos Quimicos, Biotecnologicos y Ambientales, Universidad Tecnica Federico Santa Maria, Avenida Espana 1680, Valparaiso (Chile); Grandon, Rodrigo [Departamento de Procesos Quimicos, Biotecnologicos y Ambientales, Universidad Tecnica Federico Santa Maria, Avenida Espana 1680, Valparaiso (Chile)

    2007-02-25

    Arsenic removal from wastewater is a key problem for copper smelters. This work shows results of electrocoagulation of aqueous solutions containing arsenic with three different process designs and operating parameters. Three types of electrocoagulation reactors were tested and compared: (a) a modified flow continuous reactor, (b) a turbulent flow reactor and (c) an airlift reactor. All used iron as sacrificial anodes. The results showed that the electrocoagulation process of a 100 mg/L As(V) solution could decrease the arsenic concentration to less than 2 mg/L in the effluent with a current density of 1.2 A/dm{sup 2} with both the modified flow and the airlift reactor. The removal of arsenic with the turbulent flow reactor did not reach the same level but the Fe-to-As ratio (mol/mol) achieved in the coagulation process was in this case lower (approximately 7) than with the other two reactors. In addition, it seems that increasing the current density beyond a maximum value, the electrocoagulation process would not improve any further. This could probably be explained by passivation of the anode.

  5. Comparative Analysis of Master of Industrial Design Education in Turkey

    Science.gov (United States)

    Erkarslan, Onder; Imamogullari, Beril

    2010-01-01

    This research focused on the masters degree programme in industrial design (ID), which is research and practice oriented in the light of current themes and design principles. It argued that a masters degree in industrial design would help graduates specialise in the related field and improve their skills. Therefore, institutional and academic…

  6. Designing questionnaires: healthcare survey to compare two different response scales

    Science.gov (United States)

    2014-01-01

    Background A widely discussed design issue in patient satisfaction questionnaires is the optimal length and labelling of the answering scale. The aim of the present study was to compare intra-individually the answers on two response scales to five general questions evaluating patients’ perception of hospital care. Methods Between November 2011 and January 2012, all in-hospital patients at a Swiss University Hospital received a patient satisfaction questionnaire on an adjectival scale with three to four labelled categories (LS) and five redundant questions displayed on an 11-point end-anchored numeric scale (NS). The scales were compared concerning ceiling effect, internal consistency (Cronbach’s alpha), individual item answers (Spearman’s rank correlation), and concerning overall satisfaction by calculating an overall percentage score (sum of all answers related to the maximum possible sum). Results The response rate was 41% (2957/7158), of which 2400 (81%) completely filled out all questions. Baseline characteristics of the responders and non-responders were similar. Floor and ceiling effect were high on both response scales, but more pronounced on the LS than on the NS. Cronbach’s alpha was higher on the NS than on the LS. There was a strong individual item correlation between both answering scales in questions regarding the intent to return, quality of treatment and the judgement whether the patient was treated with respect and dignity, but a lower correlation concerning satisfactory information transfer by physicians or nurses, where only three categories were available in the LS. The overall percentage score showed a comparable distribution, but with a wider spread of lower satisfaction in the NS. Conclusions Since the longer scale did not substantially reduce the ceiling effect, the type of questions rather than the type of answering scale could be addressed with a focus on specific questions about concrete situations instead of general questions

  7. Environmental effects on composite airframes: A study conducted for the ARM UAV Program (Atmospheric Radiation Measurement Unmanned Aerospace Vehicle)

    Energy Technology Data Exchange (ETDEWEB)

    Noguchi, R.A.

    1994-06-01

    Composite materials are affected by environments differently than conventional airframe structural materials are. This study identifies the environmental conditions which the composite-airframe ARM UAV may encounter, and discusses the potential degradation processes composite materials may undergo when subjected to those environments. This information is intended to be useful in a follow-on program to develop equipment and procedures to prevent, detect, or otherwise mitigate significant degradation with the ultimate goal of preventing catastrophic aircraft failure.

  8. Comparative Ergonomic Evaluation of Spacesuit and Space Vehicle Design

    Science.gov (United States)

    England, Scott; Cowley, Matthew; Benson, Elizabeth; Harvill, Lauren; Blackledge, Christopher; Perez, Esau; Rajulu, Sudhakar

    2012-01-01

    With the advent of the latest human spaceflight objectives, a series of prototype architectures for a new launch and reentry spacesuit that would be suited to the new mission goals. Four prototype suits were evaluated to compare their performance and enable the selection of the preferred suit components and designs. A consolidated approach to testing was taken: concurrently collecting suit mobility data, seat-suit-vehicle interface clearances, and qualitative assessments of suit performance within the volume of a Multi-Purpose Crew Vehicle mockup. It was necessary to maintain high fidelity in a mockup and use advanced motion-capture technologies in order to achieve the objectives of the study. These seemingly mutually exclusive goals were accommodated with the construction of an optically transparent and fully adjustable frame mockup. The construction of the mockup was such that it could be dimensionally validated rapidly with the motioncapture system. This paper describes the method used to create a space vehicle mockup compatible with use of an optical motion-capture system, the consolidated approach for evaluating spacesuits in action, and a way to use the complex data set resulting from a limited number of test subjects to generate hardware requirements for an entire population. Kinematics, hardware clearance, anthropometry (suited and unsuited), and subjective feedback data were recorded on 15 unsuited and 5 suited subjects. Unsuited subjects were selected chiefly based on their anthropometry in an attempt to find subjects who fell within predefined criteria for medium male, large male, and small female subjects. The suited subjects were selected as a subset of the unsuited medium male subjects and were tested in both unpressurized and pressurized conditions. The prototype spacesuits were each fabricated in a single size to accommodate an approximately average-sized male, so select findings from the suit testing were systematically extrapolated to the extremes

  9. Clustering of Parameter Sensitivities: Examples from a Helicopter Airframe Model Updating Exercise

    OpenAIRE

    Shahverdi, H.; C. Mares; W. Wang; J. E. Mottershead

    2009-01-01

    The need for high fidelity models in the aerospace industry has become ever more important as increasingly stringent requirements on noise and vibration levels, reliability, maintenance costs etc. come into effect. In this paper, the results of a finite element model updating exercise on a Westland Lynx XZ649 helicopter are presented. For large and complex structures, such as a helicopter airframe, the finite element model represents the main tool for obtaining accurate models which could pre...

  10. Comparative Analysis of Possible Designs for Flexible Distribution System Operation

    DEFF Research Database (Denmark)

    Lin, Jeremy; Knezovic, Katarina

    2016-01-01

    A massive amount of distributed energy resources will be connected to the distribution system in the near future. This emerging phenomenon will pose significant challenges to the traditional operation of distribution systems. This clearly calls for a growing need to develop novel grid designs...

  11. Behaviorism, Cognitivism, Constructivism: Comparing Critical Features from a Design Perspective.

    Science.gov (United States)

    Ertmer, Peggy A.; Newby, Timothy J.

    1993-01-01

    Explains three learning theories (i.e., behaviorism, cognitivism, and constructivism) and examines how each can be used for planning and conducting instructional design activities. Historical foundations are discussed, and comparisons are made concerning how learning occurs, the role of memory, how transfer occurs, and types of learning. (Contains…

  12. Behaviorism, Cognitivism, Constructivism: Comparing Critical Features from a Design Perspective.

    Science.gov (United States)

    Ertmer, Peggy A.; Newby, Timothy J.

    1993-01-01

    Explains three learning theories (i.e., behaviorism, cognitivism, and constructivism) and examines how each can be used for planning and conducting instructional design activities. Historical foundations are discussed, and comparisons are made concerning how learning occurs, the role of memory, how transfer occurs, and types of learning. (Contains…

  13. Design Effects in Web Surveys : Comparing Trained and Fresh Respondents

    NARCIS (Netherlands)

    Toepoel, V.; Das, J.W.M.; van Soest, A.H.O.

    2008-01-01

    In this paper we investigate whether there are differences in design effects between trained and fresh respondents. In three experiments, we varied the number of items on a screen, the choice of response categories, and the layout of a five point rating scale. We find that trained respondents are mo

  14. Comparative Design of 16-Bit Sparse-Tree Rsfq Adder

    Directory of Open Access Journals (Sweden)

    S. Saddam Hussain

    2014-06-01

    Full Text Available In this paper, we propse 16-bit sparse tree RSFQ adder (Rapid single flux quantam, kogge-stone adder, carry lookahead adder. In general N-bit adders like Ripple carry adder s(slow adders compare to other adders, and carry lookahead adders(area consuming adders are used in earlier days. But now the most of industries are using parallel prefix adders because of their advantages compare to kogge-stone adder, carry lookahead adder, Our prefix sparse tree adders are faster and area efficient. Parallel prefix adder is a technique for increasing the speed in DSP processor while performing addition. We simulate and synthesis different types of 16-bit sparse tree RSFQ adders using Xilinx ISE10.1i tool, By using these synthesis results, We noted the performance parameters like number of LUT’s and delay. We compare these three adders interms of LUT’s represents area and delay values.

  15. Comparative Design of 16-Bit Sparse-Tree Rsfq Adder

    OpenAIRE

    S. Saddam Hussain; S. Mahaboob Basha

    2014-01-01

    In this paper, we propse 16-bit sparse tree RSFQ adder (Rapid single flux quantam), kogge-stone adder, carry lookahead adder. In general N-bit adders like Ripple carry adder s(slow adders compare to other adders), and carry lookahead adders(area consuming adders) are used in earlier days. But now the most of industries are using parallel prefix adders because of their advantages compare to kogge-stone adder, carry lookahead adder, Our prefix sparse tree adders are faster and ar...

  16. Comparing Cost Of New Supply Chain Designs Under Uncertainty

    DEFF Research Database (Denmark)

    Wæhrens, Brian Vejrum; Kristensen, Jesper; Asmussen, Jesper Normann

    2016-01-01

    Companies pursuing improvements to their global supply chain (SC) are challenged with unravelling the true cost of operating with their supply chain design (SCD). This challenge is further intensified as SCs are faced with increasing uncertainty. To rectify this it is investigated how Cost...... Accounting, Operational Modelling and SCM inform decision making for new SCDs. Through four embedded cases, a gap is found between the practice of a global OEM and literature. Results shows complications when assessing SCDs due to limited understanding of the internal activity costs, supply chain dynamics...

  17. Learning physics: A comparative analysis between instructional design methods

    Science.gov (United States)

    Mathew, Easow

    The purpose of this research was to determine if there were differences in academic performance between students who participated in traditional versus collaborative problem-based learning (PBL) instructional design approaches to physics curricula. This study utilized a quantitative quasi-experimental design methodology to determine the significance of differences in pre- and posttest introductory physics exam performance between students who participated in traditional (i.e., control group) versus collaborative problem solving (PBL) instructional design (i.e., experimental group) approaches to physics curricula over a college semester in 2008. There were 42 student participants (N = 42) enrolled in an introductory physics course at the research site in the Spring 2008 semester who agreed to participate in this study after reading and signing informed consent documents. A total of 22 participants were assigned to the experimental group (n = 22) who participated in a PBL based teaching methodology along with traditional lecture methods. The other 20 students were assigned to the control group (n = 20) who participated in the traditional lecture teaching methodology. Both the courses were taught by experienced professors who have qualifications at the doctoral level. The results indicated statistically significant differences (p academic performance between students who participated in traditional (i.e., lower physics posttest scores and lower differences between pre- and posttest scores) versus collaborative (i.e., higher physics posttest scores, and higher differences between pre- and posttest scores) instructional design approaches to physics curricula. Despite some slight differences in control group and experimental group demographic characteristics (gender, ethnicity, and age) there were statistically significant (p = .04) differences between female average academic improvement which was much higher than male average academic improvement (˜63%) in the control

  18. Superplastic Formed Aluminum Airframe Structures. Volume 1. Executive Summary

    Science.gov (United States)

    1987-07-01

    only ten pieces. All of the substructure was combined into one waffled pan (four formers and three intercostals . The final assembly was rivet bonded... articulated by an actua- tor attached to the left hand forward corner (Figure 2). The design is complicated by a cooling air outlet vent located in... intercost - als are of two-piece construction. This is to assure proper fit between the deck and skin. Shear clips are required at each frame and

  19. Nuclear-powered Hysat spacecraft: comparative design study

    Energy Technology Data Exchange (ETDEWEB)

    Raab, B.

    1975-08-01

    The study shows that the all-nuclear spacecraft can have a substantial weight advantage over a hybrid (nuclear/solar) or all-solar spacecraft, owing to a further reduction in power requirement, and to the elimination of such equipment as the sensor gimbal and rotating joint assemblies. Because the need for a sun-oriented section is eliminated, the all-nuclear spacecraft can be designed as a monolithic structure, with the sensor and other payload firmly secured in a fixed position on the structure. This enhances attitude stability while minimizing structural weight and eliminating the need for flexible fluid lines. Sensor motion can be produced, varied, and controlled within the limits specified by the study contractors by moving the entire spacecraft in the prescribed pattern. A simple attitude control system using available hardware suffices to meet all requirements.

  20. A Comparative Study of Learning Curve Models in Defense Airframe Cost Estimating

    Science.gov (United States)

    2015-03-26

    high end sports car . The level of precision and craftsmanship required eliminates the use for certain automated 64 processes that may be present in...production process that is automated . A Bureau of Labor Statistics report identifies that percentage as very low but does not give an exact number...production of an automobile. While the process and parts are always the same, a savvy car buyer may want to avoid cars that were built on a Monday or

  1. Teaching Risk Analysis in an Aircraft Gas Turbine Engine Design Capstone Course

    Science.gov (United States)

    2016-01-01

    American Institute of Aeronautics and Astronautics 1 Teaching Risk Analysis in an Aircraft Gas Turbine Engine Design Capstone Course...introduction of risk analysis in an undergraduate aircraft engine design capstone course that is taught in concert with a companion course in airframe... design . The two preliminary designs , one for the engine and the other for the airframe, must be integrated as subsystems within a system to satisfy

  2. Comparative Study and Design of Solar Water Heater

    Directory of Open Access Journals (Sweden)

    K.Sainath,Y.krishna, Mohd Salahuddin, Mohammed Siddique Ahmed, Md Ismail, Syed Rahman,Mohammed Noman, Mohd Khaleel Ullah, Faraz Ur Rehman Azhar, Mohd Moizuddin,Mohd Riyaz Uddin.

    2014-10-01

    Full Text Available A solar water heater design is made from the plastic bottles of thumps up & plastic pipe(p.v.c run up by the centre of each solar heater in a row of bottles, these bottles act as glazing & hold reflectors made from the black paint. Solar water heaters are made of two basic parts: a solar collector that gathers radiant energy and a storage tank for the hot water inside. These systems are used to heat water for swimming pools, as well as for domestic cooking and cleaning needs. A system in which the sun’s heat is gathered by a solar collector and used to increase the temperature of a heat-transfer fluid , which flows through the pipes in the collector; the heat contained in this fluid then is conveyed and transferred to the water to be heated. Solar water heaters use the solar energy from the sun to generate heat (not electricity which can then be used to heat water for showering, space heating, industrial processes or even solar cooling. However, the research shows that the electric water spends about the 25% of its home energy costs on heating water. If we make a water heater without the collector then we can save a lot of money solar water heater do not polluted if one investing on SWH avoids carbon dioxide nitrogen oxide and sulphur dioxide and the other air pollution wastes and the utility generates power on your bum fuel to heat your household water when SWH replaces the an electric water heater. This electric displaced over 20 years replaced more than 50 tones avoided c02 emissions alone co2 traps heat in the upper most atmosphere thus, contributing to the ‘Green House Effect

  3. The NASA/Industry Design Analysis Methods for Vibrations (DAMVIBS) Program - A government overview. [of rotorcraft technology development using finite element method

    Science.gov (United States)

    Kvaternik, Raymond G.

    1992-01-01

    An overview is presented of government contributions to the program called Design Analysis Methods for Vibrations (DAMV) which attempted to develop finite-element-based analyses of rotorcraft vibrations. NASA initiated the program with a finite-element modeling program for the CH-47D tandem-rotor helicopter. The DAMV program emphasized four areas including: airframe finite-element modeling, difficult components studies, coupled rotor-airframe vibrations, and airframe structural optimization. Key accomplishments of the program include industrywide standards for modeling metal and composite airframes, improved industrial designs for vibrations, and the identification of critical structural contributors to airframe vibratory responses. The program also demonstrated the value of incorporating secondary modeling details to improving correlation, and the findings provide the basis for an improved finite-element-based dynamics design-analysis capability.

  4. Structural concept trends for commercial supersonic cruise aircraft design

    Science.gov (United States)

    Sakat, I. F.; Davis, G. W.; Saelman, B.

    1980-01-01

    Structural concept trends for future commercial supersonic transport aircraft are considered. Highlights, including the more important design conditions and requirements, of two studies are discussed. Knowledge of these design parameters, as determined through studies involving the application of flexible mathematical models, enabled inclusion of aeroelastic considerations in the structural-material concepts evaluation. The design trends and weight data of the previous contractual study of Mach 2.7 cruise aircraft were used as the basis for incorporating advanced materials and manufacturing approaches to the airframe for reduced weight and cost. Structural studies of design concepts employing advanced aluminum alloys, advanced composites, and advanced titanium alloy and manufacturing techniques are compared for a Mach 2.0 arrow-wing configuration concept. Appraisals of the impact of these new materials and manufacturing concepts to the airframe design are shown and compared. The research and development to validate the potential sources of weight and cost reduction identified as necessary to attain a viable advanced commercial supersonic transport are discussed.

  5. Application of MEMS Microphone Array Technology to Airframe Noise Measurements

    Science.gov (United States)

    Humphreys, William M., Jr.; Shams, Qamar A.; Graves, Sharon S.; Sealey, Bradley S.; Bartram, Scott M.; Comeaux, Toby

    2005-01-01

    Current generation microphone directional array instrumentation is capable of extracting accurate noise source location and directivity data on a variety of aircraft components, resulting in significant gains in test productivity. However, with this gain in productivity has come the desire to install larger and more complex arrays in a variety of ground test facilities, creating new challenges for the designers of array systems. To overcome these challenges, a research study was initiated to identify and develop hardware and fabrication technologies which could be used to construct an array system exhibiting acceptable measurement performance but at much lower cost and with much simpler installation requirements. This paper describes an effort to fabricate a 128-sensor array using commercially available Micro-Electro-Mechanical System (MEMS) microphones. The MEMS array was used to acquire noise data for an isolated 26%-scale high-fidelity Boeing 777 landing gear in the Virginia Polytechnic Institute and State University Stability Tunnel across a range of Mach numbers. The overall performance of the array was excellent, and major noise sources were successfully identified from the measurements.

  6. Feedback strategies for visual search in airframe structural inspection.

    Science.gov (United States)

    Gramopadhye, A K; Drury, C G; Sharit, J

    1997-05-01

    Feedback of information has consistently shown positive results in human inspection, provided it is given in a timely and appropriate manner. Feedback serves as the basis of most training schemes; traditionally this has been performance feedback. Other forms of feedback which provide strategy information rather than performance information may have a role in improving inspection. This study compared performance feedback and cognitive feedback in a realistic simulation of an aircraft structural inspection task. Performance (time, errors) feedback showed the greatest improvements in performance measures. Cognitive feedback enhanced efficiency measures of search strategy. When cognitive feedback consisted of visual representations of the path and the coverage of the search sequence, subjects also were able to use this task information to improve their search performance.

  7. Nanostitched Composites with Improved Interlaminar and Intralaminar Strengths for Advanced Airframes in Sea based Aviation

    Science.gov (United States)

    2017-04-13

    with   large  resin-­‐ rich  (pure  polymer)  regions.  This  was  not  observed  in  the  AS4/8552  UD  prepreg  to...34  MIT  Aero/Astro  SM  Thesis,  February  2016.   19.  http://www.onr.navy.mil/en/ Media -­‐Center/Fact-­‐Sheets/Airframe-­‐Structures

  8. Comparing Personal Characteristic Factors of Imagination between Expert and Novice Designers within Different Product Design Stages

    Science.gov (United States)

    Huang, Yinghsiu; Li, Jianyou

    2015-01-01

    Imagination plays a key role in various domains in helping to create innovative ideas, drawings, poems, movies, products, etc. In product design domain, the personal characteristics of imagination are crucial abilities for conceiving novel ideas during design processes. This study focuses on personal characteristic differences and similarities…

  9. Does decision documentation help junior designers rationalize their decisions? A comparative multiple-case study

    NARCIS (Netherlands)

    Heesch, U. van; Avgeriou, P.; Tang, A.

    2013-01-01

    Software architecture design is challenging, especially for junior software designers. Lacking practice and experience, junior designers need process support in order to make rational architecture decisions. In this paper, we present the results of a comparative multiple-case study conducted to find

  10. Improved StrongARM latch comparator: Design, analysis and performance evaluation

    KAUST Repository

    Almansouri, Abdullah

    2017-07-13

    This paper presents an improved StrongARM latch comparator, designed and simulated in 90nm and 32nm CMOS technologies. The proposed design provides an improvement of 7% in energy efficiency, 14% in speed and an average reduction of 41% in the clock feedthrough, compared to the conventional design. The new architecture also minimizes the area by reducing the required transistors needed for the enhanced performance.

  11. Development and Calibration of a Field-Deployable Microphone Phased Array for Propulsion and Airframe Noise Flyover Measurements

    Science.gov (United States)

    Humphreys, William M., Jr.; Lockard, David P.; Khorrami, Mehdi R.; Culliton, William G.; McSwain, Robert G.; Ravetta, Patricio A.; Johns, Zachary

    2016-01-01

    A new aeroacoustic measurement capability has been developed consisting of a large channelcount, field-deployable microphone phased array suitable for airframe noise flyover measurements for a range of aircraft types and scales. The array incorporates up to 185 hardened, weather-resistant sensors suitable for outdoor use. A custom 4-mA current loop receiver circuit with temperature compensation was developed to power the sensors over extended cable lengths with minimal degradation of the signal to noise ratio and frequency response. Extensive laboratory calibrations and environmental testing of the sensors were conducted to verify the design's performance specifications. A compact data system combining sensor power, signal conditioning, and digitization was assembled for use with the array. Complementing the data system is a robust analysis system capable of near real-time presentation of beamformed and deconvolved contour plots and integrated spectra obtained from array data acquired during flyover passes. Additional instrumentation systems needed to process the array data were also assembled. These include a commercial weather station and a video monitoring / recording system. A detailed mock-up of the instrumentation suite (phased array, weather station, and data processor) was performed in the NASA Langley Acoustic Development Laboratory to vet the system performance. The first deployment of the system occurred at Finnegan Airfield at Fort A.P. Hill where the array was utilized to measure the vehicle noise from a number of sUAS (small Unmanned Aerial System) aircraft. A unique in-situ calibration method for the array microphones using a hovering aerial sound source was attempted for the first time during the deployment.

  12. 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.

  13. Design of Low Power & High Speed Comparator with 0.18µm Technology for ADC Application

    Directory of Open Access Journals (Sweden)

    Rohit Mongre

    2014-08-01

    Full Text Available In Analog to Digital Converter (ADC, high speed comparator influences the overall performance of ADC directly. This paper presents the high speed & low power design of a CMOS comparator. Schematic design of this comparator is fabricated in a 0.18µm UMC Technology with 1.8V power supply and simulated in cadence Virtuoso. Simulation results are presented and it shows that this design can work under high speed of 0.8108 GHz. The design has a low offset voltage, low power dissipation 108.0318µw. In addition we have verified present results with schematic view design and also compared these results with earlier reported work and got improvement in this reported work.

  14. Numerical investigation of tandem-cylinder aerodynamic noise and its control with application to airframe noise

    Science.gov (United States)

    Eltaweel, Ahmed

    Prediction and reduction of airframe noise are critically important to the development of quieter civil transport aircraft. The key to noise reduction is a full understanding of the underlying noise source mechanisms. In this study, tandem cylinders in cross-flow as an idealization of a complex aircraft landing gear configuration are considered to investigate the noise generation and its reduction by flow control using single dielectric barrier discharge plasma actuators. The flow over tandem cylinders at ReD = 22, 000 with and without plasma actuation is computed using large-eddy simulation. The plasma effect is modeled as a body force obtained from a semi-empirical model. The flow statistics and surface pressure frequency spectra show excellent agreement with previous experimental measurements. For acoustic calculations, a boundary-element method is implemented to solve the convected Lighthill equation. The solution method is validated in a number of benchmark problems including flows over a cylinder, a rod-airfoil configuration, and a sphere. With validated flow field and acoustic solver, acoustic analysis is performed for the tandem-cylinder configuration to extend the experimental results and understand the mechanisms of noise generation and its control. Without flow control, the acoustic field is dominated by the interaction between the downstream cylinder and the upstream wake. Through suppression of vortex shedding from the upstream cylinder, the interaction noise is reduced drastically by the plasma flow control, and the vortex-shedding noise from the downstream cylinder becomes equally important. At a free-stream Mach number of 0.2, the peak sound pressure level is reduced by approximately 16 dB. This suggests the viability of plasma actuation for active control of airframe noise. The numerical investigation is extended to the noise from a realistic landing gear experimental model. Coarse-mesh computations are performed, and preliminary results are

  15. State of the Art in Beta Titanium Alloys for Airframe Applications

    Science.gov (United States)

    Cotton, James D.; Briggs, Robert D.; Boyer, Rodney R.; Tamirisakandala, Sesh; Russo, Patrick; Shchetnikov, Nikolay; Fanning, John C.

    2015-06-01

    Beta titanium alloys were recognized as a distinct materials class in the 1950s, and following the introduction of Ti-13V-11Cr-3Al in the early 1960s, intensive research occurred for decades thereafter. By the 1980s, dozens of compositions had been explored and sufficient work had been accomplished to warrant the first major conference in 1983. Metallurgists of the time recognized beta alloys as highly versatile and capable of remarkable property development at much lower component weights than steels, coupled with excellent corrosion resistance. Although alloys such as Ti-15V-3Al-3Sn-3Cr, Ti-10V-2Fe-3Al and Ti-3AI-8V-6Cr-4Mo-4Zr (Beta C) were commercialized into well-known airframe systems by the 1980s, Ti-13V-11Cr-3Al was largely discarded following extensive employment on the SR-71 Blackbird. The 1990s saw the implementation of specialty beta alloys such as Beta 21S and Alloy C, in large part for their chemical and oxidation resistance. It was also predicted that by the 1990s, cost would be the major limitation on expansion into new applications. This turned out to be true and is part of the reason for some stagnation in commercialization of new such compositions over the past two decades, despite a good understanding of the relationships among chemistry, processing, and performance and some very attractive offerings. Since then, only a single additional metastable beta alloy, Ti-5Al-5V-5Mo-3Cr-0.5Fe, has been commercialized in aerospace, although low volumes of other chemistries have found a place in the biomedical implant market. This article examines the evolution of this important class of materials and the current status in airframe applications. It speculates on challenges for expanding their use.

  16. Integrated Airframe Design Technology (Les Technologies pour la Conception Integree des Cellules)

    Science.gov (United States)

    1993-12-01

    tunnel results can be fened structure ( a variation of blade stiffened). The optimiza- applied to the structural model via the mapping process. tion...effect on loads and structures are - oscillating " acceptable Load Level and "runaway". (see Fig. 10) These have to be studied in their loads To a...Aileron- Oscillating Allowed Surface Deflection Acceptable by Static Loads Envelope Gust induced nicrer-rital load factor LODAILERON DEMAND ;;AILERON

  17. ICAM Manufacturing Cost/Design Guide. Volume 3. Airframes. User’s Manual.

    Science.gov (United States)

    1983-01-01

    Aluminum 356/ A356 ... Aluminum Investment Cast Investment Cast 2 2 z -N ±0.01 ±0.02 ±0.03 100 ±0.02 ±0.03 356/ A356 Aluminum 356/ A356 Aluminum 2 ____Sand C.,ast 2Sand Cast 2 2 -oo... ALUMINUM D OR C WITH 10% B +15% SAND CAST D OR C WITH 50% B +25% B +50% 356/ A356 D OR C BASE ALUMINUM D OR C WITH 10% B +10% INVESTMENT D OK. WITH

  18. ICAM Manufacturing Cost/Design Guide. Volume 2. Airframes. User’s Manual.

    Science.gov (United States)

    1983-01-01

    Aluminum Q0-A-601 356 A356 MIL-A-21180 Sand AMS 4218 Investment 17-4 PH AMS 5355 BOX...tll•. 4) 0 -•orr rr 0 0 ±0.01 -1-0.02 ____.0.03 __.+-0.01 ±0.02 +__0.03 356/ A356 Aluminum 356/ A356 Aluminum Investment Cast Investment Cast 2 2 n- O 0...0.01 ::t:0.02 -!-0.03 _+0.01 _+0.02 _+0.03 .., 356/ A356 Aluminum 356/ A356 Aluminum ,,." Sand Cast Sand Cast S2 2 S- 8 0 ’ 0 •_0103 -: • ÷0 02

  19. Developing a new dental implant design and comparing its biomechanical features with four designs.

    Science.gov (United States)

    Rismanchian, Mansour; Birang, Reza; Shahmoradi, Mahdi; Talebi, Hassan; Zare, Reza Jabar

    2010-01-01

    As various implant geometries present different biomechanical behaviors, the purpose of this work was to study stress distribution around tapered and cylindrical threaded implant geometries using three-dimensional finite element stress analysis. Seven implant models were constructed using Computer Assisted Designing system. After digitized models of mandibular section, the crowns were created. They were combined with implant models, which were previously imported into CATIA software. The combined solid model was transferred to ABAQOUS to create a finite element meshed model which was later analyzed regarding the highest maximum and minimum principal stresses of bone. For all models, the highest stresses of cortical bone were located at the crestal cortical bone around the implant. Threaded implants, triangular thread form and taper body form showed a higher peak of tensile and compressive stress than non-threaded implants, square thread form and straight body form, respectively. A taper implant with triangular threads, which is doubled in the cervical portion of the body, had a significantly lower peak of tensile and compressive stress in the cortical bone than straight/taper triangular or square threaded implant forms. For the investigation of bone implant interfacial stress, the non-bonded state should be studied too. Confirmative clinical and biological studies are required in order to benefit from the results of this study.

  20. Developing a new dental implant design and comparing its biomechanical features with four designs

    Directory of Open Access Journals (Sweden)

    Mansour Rismanchian

    2010-01-01

    Full Text Available Background: As various implant geometries present different biomechanical behaviors, the purpose of this work was to study stress distribution around tapered and cylindrical threaded implant geometries using three-dimensional finite element stress analysis. Methods : Seven implant models were constructed using Computer Assisted Designing system. After digitized models of mandibular section, the crowns were created. They were combined with implant models, which were previously imported into CATIA software. The combined solid model was transferred to ABAQOUS to create a finite element meshed model which was later analyzed regarding the highest maximum and minimum principal stresses of bone. Results: For all models, the highest stresses of cortical bone were located at the crestal cortical bone around the implant. Threaded implants, triangular thread form and taper body form showed a higher peak of tensile and compressive stress than non-threaded implants, square thread form and straight body form, respectively. A taper implant with triangular threads, which is doubled in the cervical portion of the body, had a significantly lower peak of tensile and compressive stress in the cortical bone than straight/taper triangular or square threaded implant forms. Conclusion: For the investigation of bone implant interfacial stress, the non-bonded state should be studied too. Confirmative clinical and biological studies are required in order to benefit from the results of this study.

  1. Comparing Simple and Advanced Video Tools as Supports for Complex Collaborative Design Processes

    Science.gov (United States)

    Zahn, Carmen; Pea, Roy; Hesse, Friedrich W.; Rosen, Joe

    2010-01-01

    Working with digital video technologies, particularly advanced video tools with editing capabilities, offers new prospects for meaningful learning through design. However, it is also possible that the additional complexity of such tools does "not" advance learning. We compared in an experiment the design processes and learning outcomes…

  2. Comparing Simple and Advanced Video Tools as Supports for Complex Collaborative Design Processes

    Science.gov (United States)

    Zahn, Carmen; Pea, Roy; Hesse, Friedrich W.; Rosen, Joe

    2010-01-01

    Working with digital video technologies, particularly advanced video tools with editing capabilities, offers new prospects for meaningful learning through design. However, it is also possible that the additional complexity of such tools does "not" advance learning. We compared in an experiment the design processes and learning outcomes of 24…

  3. Constructive Synergy in Design Science Research: A Comparative Analysis of Design Science Research and the Constructive Research Approach

    DEFF Research Database (Denmark)

    Piirainen, Kalle; Gonzalez, Rafael A.

    2014-01-01

    Information systems research is focused on creating knowledge which can be applied in organizations. Design science research, which specifically aims at applying existing knowledge to solve interesting and relevant business problems, has been steadily gaining support in information systems research....... However, design science research is not the only design-oriented research framework available. Accordingly, this raises the question of whether there is something to learn between the different approaches. This paper contributes to answering this question by comparing design science research...... with the constructive research approach. The conclusion is that the two approaches are similar and compatible, save for details in practical requirements and partly underlying philosophical assumptions. The main finding that arises from the comparison is, however, that there is a potential problem in claiming knowledge...

  4. A Unified Framework for Estimating Minimum Detectable Effects for Comparative Short Interrupted Time Series Designs

    Science.gov (United States)

    Price, Cristofer; Unlu, Fatih

    2014-01-01

    The Comparative Short Interrupted Time Series (C-SITS) design is a frequently employed quasi-experimental method, in which the pre- and post-intervention changes observed in the outcome levels of a treatment group is compared with those of a comparison group where the difference between the former and the latter is attributed to the treatment. The…

  5. Design as a Condition for Prosperity in Czech Businesses - A Comparative Study

    Directory of Open Access Journals (Sweden)

    Kramolis Jan

    2015-12-01

    Full Text Available The purpose of the paper is to comprehensively review the sources of design management, business prosperity and competitiveness. The study shows the current situation in Czech businesses. Furthermore, this paper also attempts to analyze and identify the awareness of companies concerning the relation to design as a condition for business prosperity. The primary aim of the research is to investigate design as a condition of prosperity in Czech businesses. A comprehensive review of the extant literature and journals identified several sources of design approach and various definitions of business prosperity. The research consists of two main parts. Firstly, a method of smart internet questionnaires designed by the author was used. After that, the data were analyzed using mosaic plot and elementary statistics calculations, and seeking mutual dependence, followed by a comparative method. Finally, the findings were processed by comparative study that aims to compare the years 2012 and 2014. The results of the research offer interesting findings. This paper identifies several interesting aspects regarding design within Czech companies, including the mindset of management (the insight gap of Czech businesses regarding design in their business.

  6. Perspectives on Prediction Variance and Bias in Developing, Assessing, and Comparing Experimental Designs

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F.

    2010-12-01

    The vast majority of response surface methods used in practice to develop, assess, and compare experimental designs focus on variance properties of designs. Because response surface models only approximate the true unknown relationships, models are subject to bias errors as well as variance errors. Beginning with the seminal paper of Box and Draper (1959) and over the subsequent 50 years, methods that consider bias and mean-squared-error (variance and bias) properties of designs have been presented in the literature. However, these methods are not widely implemented in software and are not routinely used to develop, assess, and compare experimental designs in practice. Methods for developing, assessing, and comparing response surface designs that account for variance properties are reviewed. Brief synopses of publications that consider bias or mean-squared-error properties are provided. The difficulties and approaches for addressing bias properties of designs are summarized. Perspectives on experimental design methods that account for bias and/or variance properties and on future needs are presented.

  7. High-Maneuverability Airframe: Initial Investigation of Configuration’s Aft End for Increased Stability, Range, and Maneuverability

    Science.gov (United States)

    2013-09-01

    High-Maneuverability Airframe: Initial Investigation of Configuration’s Aft End for Increased Stability, Range, and Maneuverability by Sidra ...for Increased Stability, Range, and Maneuverability Sidra I. Silton and Frank Fresconi Weapons and Materials Research Directorate, ARL...Maneuverability 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Sidra I. Silton and Frank Fresconi 5d. PROJECT

  8. The attitude of Czech companies towards designcomparative study of 2012 and 2014

    Directory of Open Access Journals (Sweden)

    J. Kramoliš

    2016-06-01

    Full Text Available The aim of the article. The aim of this paper is to comprehensively review of the sources of design management and links between design and business prosperity. The study shows current situation in Czech business in the years 2012 and 2014. Furthermore, this paper also attempts to analyse (comparative study and identify the awareness of companies concerning design as a condition of business prosperity. The primary aim of the research is to compare managers’ attitude to design in Czech businesses. The results of the analysis. A comprehensive review of the extant literature and journals identified several sources of design approach as well as various definitions of design management. The research consists of two main parts. Firstly, method of smart internet questionnaires was used. After that, the data were analysed using mosaic plot and elementary statistics calculations and verifying hypotheses. Then, a comparative method was used. Finally, the findings were processed by a comparative study that aims to make comparisons within the years 2012 and 2014. Managers feel the impact of design in three surveyed areas more negatively in 2014 than in 2012. Conclusions and directions of further researches. The results of the research offer interesting findings that indicate change in attitudes. This paper identifies several interesting aspects regarding design within Czech companies, including the mind-set of management. Briefly concluded: “It can still argue that design plays an important role in most businesses in the Czech Republic”. Many managers, however, do not have conclusive evidence directly linked to a potential success of their company. This problem could be solved by further research.

  9. Power calculation for comparing diagnostic accuracies in a multi-reader, multi-test design.

    Science.gov (United States)

    Kim, Eunhee; Zhang, Zheng; Wang, Youdan; Zeng, Donglin

    2014-12-01

    Receiver operating characteristic (ROC) analysis is widely used to evaluate the performance of diagnostic tests with continuous or ordinal responses. A popular study design for assessing the accuracy of diagnostic tests involves multiple readers interpreting multiple diagnostic test results, called the multi-reader, multi-test design. Although several different approaches to analyzing data from this design exist, few methods have discussed the sample size and power issues. In this article, we develop a power formula to compare the correlated areas under the ROC curves (AUC) in a multi-reader, multi-test design. We present a nonparametric approach to estimate and compare the correlated AUCs by extending DeLong et al.'s (1988, Biometrics 44, 837-845) approach. A power formula is derived based on the asymptotic distribution of the nonparametric AUCs. Simulation studies are conducted to demonstrate the performance of the proposed power formula and an example is provided to illustrate the proposed procedure.

  10. Comparing infants' use of featural and spatiotemporal information when individuating objects in an event monitoring design

    DEFF Research Database (Denmark)

    Krøjgaard, Peter

    , to what extent infants rely on spatiotemporal or featural object information when individuating objects is currently under debate. Hitherto, infants' use of spatiotemporal and featural object information has only been compared directly using the rather cognitively demanding event mapping design....... The results obtained using this design reveal that infants are more successful using spatiotemporal object information than when using featural information. However, recent studies using the less cognitively demanding event monitoring design have revealed that even younger infants are capable of object...... in the present series of experiments in which infants' use of spatiotemporal and featural information is compared directly using the less demanding event monitoring design. The results are discussed in relation to existing empirical evidence....

  11. A Comparative Analysis of Low Power and Area Efficient Digital Circuit Design

    OpenAIRE

    B. Dilli Kumar; Chandra Babu, A.; Prasad, V.

    2013-01-01

    VLSI design technology. If the power consumption is less, then the amount of power dissipation is also less. The power dissipation of a device can be reduced by using different low power techniques. In the present paper the performance of 4x1 multiplexer in different low power techniques was analyzed and its power dissipation in those techniques is compared with the conventional CMOS design. Each of these techniques has different advantages depending on their logic of operation. The simulatio...

  12. Design and Implementation of 16-Bit Magnitude Comparator Using Efficient Low Power High Performance Full Adders

    Directory of Open Access Journals (Sweden)

    Ajaykumar S Kulkarni

    2014-08-01

    Full Text Available In VLSI applications, area, delay and power are the important factors which must be taken into account in the design of a fast adder [1]. The paper attempts to examine the features of certain adder circuits which promise superior performance compared to existing circuits. The advantages of these circuits are low-power consumption, a high degree of regularity and simplicity. In this paper, the design of a 16-bit comparator is proposed. Magnitude comparison is one of the basic functions used for sorting in microprocessor, digital signal processing, so a high performance, effective magnitude comparator is required. The main objective of this paper is to provide new low power, area solution for Very Large Scale Integration (VLSI designers using low power high performance efficient full adders.

  13. 利用机体遮挡实现机载抗干扰通信%Airborne Anti-jamming Communication by Airframe Antenna Shading

    Institute of Scientific and Technical Information of China (English)

    曹劲; 彭笠

    2014-01-01

    According to the engineering requirement of airborne anti-jamming communication design,the airframe shading effect on typical forward,rear,left and right distributed VHF/UHF and L-band antennas on the airplane is analyzed. Based on the principle of signal suppression by airframe shading,an anti-jam-ming communication method is proposed by smartly using the left or right wing mounted antenna which faces the communication signal when communication and interference signal comes from different sides of the airplane respectively. The method can be realized easily in engineering because it only needs two new installed wing mounted antennas and two RF switches. The simulation result shows that the method can ef-fectively suppress the interference signal reception from the side of the airplane and the maximal suppres-sion can reach 35 dB. The method provides a new technical solution and theoretical implemental guide for airborne anti-jamming communication design.%结合机载通信抗干扰设计的工程应用需求,分析了机体遮挡对机身前后左右典型安装位置VHF/UHF和L频段通信天线的影响程度,提出了一种当通信信号和干扰信号分别位于机身两侧时,应用机体遮挡对信号接收的抑制原理,通过选择指向通信信号一侧的左或右机翼天线实现抗干扰通信的方法。该方法仅需新增两副机翼天线和两个射频开关,具备较强的工程可实现性。仿真结果表明该方法能够有效抑制来自机身侧面干扰信号的接收,最大抑制达到35 dB,为机载通信抗干扰能力提升设计提供了新的技术途径和理论指导。

  14. UniPrimer: A Web-Based Primer Design Tool for Comparative Analyses of Primate Genomes

    Directory of Open Access Journals (Sweden)

    Nomin Batnyam

    2012-01-01

    Full Text Available Whole genome sequences of various primates have been released due to advanced DNA-sequencing technology. A combination of computational data mining and the polymerase chain reaction (PCR assay to validate the data is an excellent method for conducting comparative genomics. Thus, designing primers for PCR is an essential procedure for a comparative analysis of primate genomes. Here, we developed and introduced UniPrimer for use in those studies. UniPrimer is a web-based tool that designs PCR- and DNA-sequencing primers. It compares the sequences from six different primates (human, chimpanzee, gorilla, orangutan, gibbon, and rhesus macaque and designs primers on the conserved region across species. UniPrimer is linked to RepeatMasker, Primer3Plus, and OligoCalc softwares to produce primers with high accuracy and UCSC In-Silico PCR to confirm whether the designed primers work. To test the performance of UniPrimer, we designed primers on sample sequences using UniPrimer and manually designed primers for the same sequences. The comparison of the two processes showed that UniPrimer was more effective than manual work in terms of saving time and reducing errors.

  15. Design of near-perfect-reconstructed transmultiplexer using different modulation techniques: A comparative study

    Directory of Open Access Journals (Sweden)

    A. Vishwakarma

    2017-07-01

    Full Text Available In this paper, an efficient iterative method for design of near-perfect reconstructed transmultiplexer (NPR TMUX is proposed for the prescribed roll-off factor (RF and stop band attenuation (As. In this method, windowing technique has been used for the design of prototype filter, and different modulation techniques have been exploited for designing multi-channel transmultiplexer (TMUX. In this method, inter-channel interference (ICI is iteratively minimized so that it approximately reduces to ideal value zero. Design example is given to illustrate the superiority of the proposed method over earlier reported work. A comparative study of the performance of different modulation techniques for designing TMUX is also presented.

  16. Design of A Novel High Speed Dynamic Comparator with Low Power Dissipation for High Speed ADCs

    Directory of Open Access Journals (Sweden)

    Sougata Ghosh

    2013-01-01

    Full Text Available A new CMOS dynamic comparator using dual input single output differential amplifier as latch stage suitable for high speed analog-to-digital converters with High Speed, low power dissipation and immune to noise than the previous reported work is proposed. Back to-back inverter in the latch stage is replaced with dual-input single output differential amplifier. This topology completely removes the noise that is present in the input. The structure shows lower power dissipation and higher speed than the conventional comparators. The circuit is simulated with 1V DC supply voltage and 250 MHz clock frequency. The proposed topology is based on two cross coupled differential pairs positive feedback and switchable current sources, has a lower power dissipation, higher speed, less area, and it is shown to be very robust against transistor mismatch, noise immunity. Previous reported comparators are designed and simulated their DC response and Transient response in Cadence®Virtuoso Analog Design Environment using GPDK 90nm technology. Layouts of the proposed comparator have been done in Cadence® Virtuoso Layout XL Design Environment. DRC and LVS has been checked and compared with the corresponding circuits and RC extracted diagram has been generated. After that post layout simulation with 1V supply voltage has been done and compared the speed, power dissipation, Area, delay with the results before layout and the superior features of the proposed comparator are established

  17. A comparative study on the customized design of mandibular reconstruction plates using finite element method

    Directory of Open Access Journals (Sweden)

    Abdulrahman Al-Ahmari

    2015-07-01

    Full Text Available Mandible defects and its deformities are serious complications and its precise reconstruction is one of the most challenging tasks in oral maxillofacial surgery. The commercially available standard mandible implants are manually bended before surgery to custom fit the patient’s jaw. A slight mismatch in the plate and bone alignment may result in the implant failure. However, with the integration of computer-aided design, rapid prototyping, and advanced imaging systems (computed tomography or magnetic resonance imaging, it is possible to produce a customized mandible implant that can precisely fit the patient’s jaw. The aim of this article is to compare a new design of customized mandible implant (sinewave plate and compare it with the commonly used straight implant design. The finite element–simulated results reveal that the commonly used straight reconstruction plates are more prone to loosening of the screws due to its higher strain concentration on the screw hole when compared to newly designed sinewave reconstruction plate. Moreover, the straight plate is more sensitive to the chewing load variations and develops almost 20% increase in the stresses when compared to sinewave plate. The study reveals that the sinewave reconstruction plate can significantly enhance the stability and safety of the mandible implant.

  18. Energy Efficiency and Universal Design in Home Renovations - A Comparative Review.

    Science.gov (United States)

    Kapedani, Ermal; Herssens, Jasmien; Verbeeck, Griet

    2016-01-01

    Policy and societal objectives indicate a large need for housing renovations that both accommodate lifelong living and significantly increase energy efficiency. However, these two areas of research are not yet examined in conjunction and this paper hypothesizes this as a missed opportunity to create better renovation concepts. The paper outlines a comparative review on research in Energy Efficiency and Universal Design in order to find the similarities and differences in both depth and breadth of knowledge. Scientific literature in the two fields reveals a disparate depth of knowledge in areas of theory, research approach, and degree of implementation in society. Universal Design and Energy Efficiency are part of a trajectory of expanding scope towards greater sustainability and, although social urgency has been a driver of the research intensity and approach in both fields, in energy efficiency there is an engineering, problem solving approach while Universal Design has a more sociological, user-focused one. These different approaches are reflected in the way home owners in Energy Efficiency research are viewed as consumers and decision makers whose drivers are studied, while Universal Design treats home owners as informants in the design process and studies their needs. There is an inherent difficulty in directly merging Universal Design and Energy Efficiency at a conceptual level because Energy Efficiency is understood as a set of measures, i.e. a product, while Universal Design is part of a (design) process. The conceptual difference is apparent in their implementation as well. Internationally energy efficiency in housing has been largely imposed through legislation, while legislation directly mandating Universal Design is either non-existent or it has an explicit focus on accessibility. However, Energy Efficiency and Universal Design can be complementary concepts and, even though it is more complex than expected, the combination offers possibilities to advance

  19. Site Planning Here and There: Comparing Western Site Planning and Design and Eastern Feng Shui

    Directory of Open Access Journals (Sweden)

    Mintai Kim

    2004-06-01

    Full Text Available Feng Shui, in comparison with contemporary site design tools, employs a broad range of criteria in the observation and assessment of a site. Feng Shui includes information that is gathered at a different level of awareness and used to define what it is that causes a space to feel the way it does. As a result, Feng Shui may better respond to human needs and perceptions by providing the physical conditions that are comfortable for people using the space. One of the intentions of this study is to close the gap between Western ('here' and Eastern ('there' ideas. This study examines 1 whether or not Feng Shui and Western site planning are comparable, and 2 if Feng Shui can be a valid planning, design and evaluation tool for modern site planning. We examine and compare urban plazas from both Feng Shui and Western site planning perspectives. The study assessed a variety of existing urban places in the Tucson and Phoenix metropolitan areas, and Sedona, Arizona for conditions of human comfort as measured by 1 Feng Shui principles, and 2 contemporary site design recommendations. This study used the principles of Feng Shui as the criteria for evaluation of urban spaces based on human needs for physical comfort. Results of this study indicate that places that are well designed from a Feng Shui point of view are also perceived as well designed from a contemporary site design vantage. The outcome suggests that Feng Shui is a valuable tool in the site design process for Western designers.

  20. Is there a clinical benefit with a smooth compensator design compared with a plunged compensator design for passive scattered protons?

    Energy Technology Data Exchange (ETDEWEB)

    Tabibian, Art A., E-mail: art.tabibian@gmail.com [University of Texas School of Allied Health-Medical Dosimetry, Houston, TX (United States); Powers, Adam; Dolormente, Keith; Oommen, Sneha; Tiwari, Akhil [University of Texas School of Allied Health-Medical Dosimetry, Houston, TX (United States); Palmer, Matt [MD Anderson Department of Radiation Oncology, Houston, TX (United States); Zhu, Xiaorong R.; Li, Heng; Sahoo, Narayan; Wisdom, Paul [MD Anderson Department of Radiation Physics, Houston, TX (United States); Velasco, Kyle [Radiation Oncology Resources, Goshen, IN (United States); Erhart, Kevin; Stanley, Henry [Decimal, Inc, Sanford, FL (United States); Nguyen, Bao-Ngoc T. [MD Anderson Department of Radiation Oncology, Houston, TX (United States)

    2015-04-01

    In proton therapy, passive scattered proton plans use compensators to conform the dose to the distal surface of the planning volume. These devices are custom made from acrylic or wax for each treatment field using either a plunge-drilled or smooth-milled compensator design. The purpose of this study was to investigate if there is a clinical benefit of generating passive scattered proton radiation treatment plans with the smooth compensator design. We generated 4 plans with different techniques using the smooth compensators. We chose 5 sites and 5 patients for each site for the range of dosimetric effects to show adequate sample. The plans were compared and evaluated using multicriteria (MCA) plan quality metrics for plan assessment and comparison using the Quality Reports [EMR] technology by Canis Lupus LLC. The average absolute difference for dosimetric metrics from the plunged-depth plan ranged from −4.7 to +3.0 and the average absolute performance results ranged from −6.6% to +3%. The manually edited smooth compensator plan yielded the best dosimetric metric, +3.0, and performance, + 3.0% compared to the plunged-depth plan. It was also superior to the other smooth compensator plans. Our results indicate that there are multiple approaches to achieve plans with smooth compensators similar to the plunged-depth plans. The smooth compensators with manual compensator edits yielded equal or better target coverage and normal tissue (NT) doses compared with the other smooth compensator techniques. Further studies are under investigation to evaluate the robustness of the smooth compensator design.

  1. Design Oriented Structural Modeling for Airplane Conceptual Design Optimization

    Science.gov (United States)

    Livne, Eli

    1999-01-01

    The main goal for research conducted with the support of this grant was to develop design oriented structural optimization methods for the conceptual design of airplanes. Traditionally in conceptual design airframe weight is estimated based on statistical equations developed over years of fitting airplane weight data in data bases of similar existing air- planes. Utilization of such regression equations for the design of new airplanes can be justified only if the new air-planes use structural technology similar to the technology on the airplanes in those weight data bases. If any new structural technology is to be pursued or any new unconventional configurations designed the statistical weight equations cannot be used. In such cases any structural weight estimation must be based on rigorous "physics based" structural analysis and optimization of the airframes under consideration. Work under this grant progressed to explore airframe design-oriented structural optimization techniques along two lines of research: methods based on "fast" design oriented finite element technology and methods based on equivalent plate / equivalent shell models of airframes, in which the vehicle is modelled as an assembly of plate and shell components, each simulating a lifting surface or nacelle / fuselage pieces. Since response to changes in geometry are essential in conceptual design of airplanes, as well as the capability to optimize the shape itself, research supported by this grant sought to develop efficient techniques for parametrization of airplane shape and sensitivity analysis with respect to shape design variables. Towards the end of the grant period a prototype automated structural analysis code designed to work with the NASA Aircraft Synthesis conceptual design code ACS= was delivered to NASA Ames.

  2. Unsteady Flowfield Around Tandem Cylinders as Prototype for Component Interaction in Airframe Noise

    Science.gov (United States)

    Khorrami, Meldi R.; Choudhari, Meelan M.; Jenkins, Luther N.; McGinley, Catherine B.

    2005-01-01

    Synergistic application of experiments and numerical simulations is crucial to understanding the underlying physics of airframe noise sources. The current effort is aimed at characterizing the details of the flow interaction between two cylinders in a tandem configuration. This setup is viewed to be representative of several component-level flow interactions that occur when air flows over the main landing gear of large civil transports. Interactions of this type are likely to have a significant impact on the noise radiation associated with the aircraft undercarriage. The paper is focused on two-dimensional, time-accurate flow simulations for the tandem cylinder configuration. Results of the unsteady Reynolds Averaged Navier-Stokes (URANS) computations with a two-equation turbulence model, at a Reynolds number of 0.166 million and a Mach number of 0.166, are presented. The experimental measurements of the same flow field are discussed in a separate paper by Jenkins, Khorrami, Choudhari, and McGinley (2005). Two distinct flow regimes of interest, associated with short and intermediate separation distances between the two cylinders, are considered. Emphasis is placed on understanding both time averaged and unsteady flow features between the two cylinders and in the wake of the rear cylinder. Predicted mean flow quantities and vortex shedding frequencies show reasonable agreement with the measured data for both cylinder spacings. Computations for short separation distance indicate decay of flow unsteadiness with time, which is not unphysical; however, the predicted sensitivity of mean lift coefficient to small angles of attack explains the asymmetric flowfield observed during the experiments.

  3. Healthcare outcomes assessed with observational study designs compared with those assessed in randomized trials.

    Science.gov (United States)

    Anglemyer, Andrew; Horvath, Hacsi T; Bero, Lisa

    2014-04-29

    Researchers and organizations often use evidence from randomized controlled trials (RCTs) to determine the efficacy of a treatment or intervention under ideal conditions. Studies of observational designs are often used to measure the effectiveness of an intervention in 'real world' scenarios. Numerous study designs and modifications of existing designs, including both randomized and observational, are used for comparative effectiveness research in an attempt to give an unbiased estimate of whether one treatment is more effective or safer than another for a particular population.A systematic analysis of study design features, risk of bias, parameter interpretation, and effect size for all types of randomized and non-experimental observational studies is needed to identify specific differences in design types and potential biases. This review summarizes the results of methodological reviews that compare the outcomes of observational studies with randomized trials addressing the same question, as well as methodological reviews that compare the outcomes of different types of observational studies. To assess the impact of study design (including RCTs versus observational study designs) on the effect measures estimated.To explore methodological variables that might explain any differences identified.To identify gaps in the existing research comparing study designs. We searched seven electronic databases, from January 1990 to December 2013.Along with MeSH terms and relevant keywords, we used the sensitivity-specificity balanced version of a validated strategy to identify reviews in PubMed, augmented with one term ("review" in article titles) so that it better targeted narrative reviews. No language restrictions were applied. We examined systematic reviews that were designed as methodological reviews to compare quantitative effect size estimates measuring efficacy or effectiveness of interventions tested in trials with those tested in observational studies

  4. Comparative effectiveness research for the clinician researcher: a framework for making a methodological design choice.

    Science.gov (United States)

    Williams, Cylie M; Skinner, Elizabeth H; James, Alicia M; Cook, Jill L; McPhail, Steven M; Haines, Terry P

    2016-01-01

    Comparative effectiveness research compares two active forms of treatment or usual care in comparison with usual care with an additional intervention element. These types of study are commonly conducted following a placebo or no active treatment trial. Research designs with a placebo or non-active treatment arm can be challenging for the clinician researcher when conducted within the healthcare environment with patients attending for treatment.A framework for conducting comparative effectiveness research is needed, particularly for interventions for which there are no strong regulatory requirements that must be met prior to their introduction into usual care. We argue for a broader use of comparative effectiveness research to achieve translatable real-world clinical research. These types of research design also affect the rapid uptake of evidence-based clinical practice within the healthcare setting.This framework includes questions to guide the clinician researcher into the most appropriate trial design to measure treatment effect. These questions include consideration given to current treatment provision during usual care, known treatment effectiveness, side effects of treatments, economic impact, and the setting in which the research is being undertaken.

  5. Study to investigate design, fabrication and test of low cost concepts for large hybrid composite helicopter fuselage, phase 2

    Science.gov (United States)

    Adams, K. M.; Lucas, J. J.

    1977-01-01

    The development of a frame/stringer/skin fabrication technique for composite airframe construction was studied as a low cost approach to the manufacturer of larger helicopter airframe components. A center cabin aluminum airframe section of the Sikorsky CH-53D, was selected for evaluation as a composite structure. The design, as developed, is composed of a woven KEVLAR R-49/epoxy skin and graphite/epoxy frames and stringers. The single cure concept is made possible by the utilization of pre-molded foam cores, over which the graphite/epoxy pre-impregnated frame and stringer reinforcements are positioned. Bolted composite channel sections were selected as the optimum joint construction. The applicability of the single cure concept to larger realistic curved airframe sections, and the durability of the composite structure in a realistic spectrum fatigue environment, was described.

  6. Comparing bioretention designs with and without an internal water storage layer for treating highway runoff.

    Science.gov (United States)

    Li, Ming-Han; Swapp, Mark; Kim, Myung Hee; Chu, Kung-Hui; Sung, Chan Yong

    2014-05-01

    This study compares the performance of a field bioretention cell with and without an internal water storage (IWS) layer for treating highway runoff. Both synthetic and natural runoff tests were conducted. Hydraulic performances on peak discharge reduction and detention time extension were measured. Pollutant removal efficiencies were evaluated for total suspended solids (TSS), copper (Cu), lead (Pb), zinc (Zn), total nitrogen, nitrate, ammonia, total phosphorus, and orthophosphate phosphorus. Pollutants in soil media were measured. Results reveal that both IWS and non-IWS designs reduced peak discharge and extended detention time, while the IWS design performed better. For water quality performance, the non-IWS design removed TSS, Cu, Pb, Zn, and total phosphorus to varying degrees of efficiency, but total nitrogen removal was minimal. The IWS layer significantly improved removal efficiencies for TSS, Cu, Zn, nitrogen, and phosphorus. Soil media accumulated some metals over time.

  7. Speech-generating devices: effectiveness of interface design-a comparative study of autism spectrum disorders.

    Science.gov (United States)

    Chen, Chien-Hsu; Wang, Chuan-Po; Lee, I-Jui; Su, Chris Chun-Chin

    2016-01-01

    We analyzed the efficacy of the interface design of speech generating devices on three non-verbal adolescents with autism spectrum disorder (ASD), in hopes of improving their on-campus communication and cognitive disability. The intervention program was created based on their social and communication needs in school. Two operating interfaces were designed and compared: the Hierarchical Relating Menu and the Pie Abbreviation-Expansion Menu. The experiment used the ABCACB multiple-treatment reversal design. The test items included: (1) accuracy of operating identification; (2) interface operation in response to questions; (3) degree of independent completion. Each of these three items improved with both intervention interfaces. The children were able to operate the interfaces skillfully and respond to questions accurately, which evidenced the effectiveness of the interfaces. We conclude that both interfaces are efficacious enough to help nonverbal children with ASD at different levels.

  8. Design of 6-Bit Flash Analog to Digital Converter Using Variable Switching Voltage CMOS Comparator

    Directory of Open Access Journals (Sweden)

    Gulrej Ahmed

    2014-04-01

    Full Text Available This paper presents the design of 6-bit flash analog to digital Converter (ADC using the new variable switching voltage (VSV comparator. In general, Flash ADCs attain the highest conversion speed at the cost of high power consumption. By using the new VSV comparator, the designed 6-bit Flash ADC exhibits significant improvement in terms of power and speed of previously reported Flash ADCs. The simulation result shows that the converter consumes peak power 2.1 mW from a 1.2 V supply and achieves the speed of 1 GHz in a 65nm standard CMOS process. The measurement of maximum differential and integral nonlinearities (DNL and INL of the Flash ADC are 0.3 LSB and 0.6 LSB respectively.

  9. Comparative Design Studies for the BESSY FEL Program using the MEDUSA and GENESIS Simulation Codes

    CERN Document Server

    Freund, H

    2005-01-01

    The BESSY FEL is based on a seeded cascade of High Gain Harmonic Generation (HGHG) sections followed by an amplifier to produce coherent and stable short wavelength output. Here, we report on comparative design studies carried out using the MEDUSA [1], and GENESIS [2] simulation codes. These two codes have each been used to successfully predict a variety of FEL designs and have agreed well with a number of important experiments. In addition, they were included in a comparative study of FEL simulation [3] that reported substantial agreement between the codes for the specific configurations studied. However, these codes are based on different assumptions. GENESIS treats the particle dynamics using a wiggler-averaged orbit approximation, the transverse electromagnetic field is treated using a field solver, and harmonics are not included. MEDUSA does not use the wiggler-averaged orbit approximation to treat particle dynamics, the transverse fields are treated using a Gaussian modal superposition, and harmonics ar...

  10. Design and Comparative Study of Three Photovoltaic Battery Charge Control Algorithms in MATLAB/SIMULINK Environment

    Directory of Open Access Journals (Sweden)

    Ankur Bhattacharjee

    2012-09-01

    Full Text Available This paper contains the design of a three stage solar battery charge controller and a comparative study of this charge control technique with three conventional solar battery charge control techniques such as 1. Constant Current (CC charging, 2. Two stage constant current constant voltage (CC-CV charging technique. The analysis and the comparative study of the aforesaid charging techniques are done in MATLAB/SIMULINK environment. Here the practical data used to simulate the charge control algorithms are based on a 12Volts 7Ah Sealed lead acid battery.

  11. Optimal two-phase sampling design for comparing accuracies of two binary classification rules.

    Science.gov (United States)

    Xu, Huiping; Hui, Siu L; Grannis, Shaun

    2014-02-10

    In this paper, we consider the design for comparing the performance of two binary classification rules, for example, two record linkage algorithms or two screening tests. Statistical methods are well developed for comparing these accuracy measures when the gold standard is available for every unit in the sample, or in a two-phase study when the gold standard is ascertained only in the second phase in a subsample using a fixed sampling scheme. However, these methods do not attempt to optimize the sampling scheme to minimize the variance of the estimators of interest. In comparing the performance of two classification rules, the parameters of primary interest are the difference in sensitivities, specificities, and positive predictive values. We derived the analytic variance formulas for these parameter estimates and used them to obtain the optimal sampling design. The efficiency of the optimal sampling design is evaluated through an empirical investigation that compares the optimal sampling with simple random sampling and with proportional allocation. Results of the empirical study show that the optimal sampling design is similar for estimating the difference in sensitivities and in specificities, and both achieve a substantial amount of variance reduction with an over-sample of subjects with discordant results and under-sample of subjects with concordant results. A heuristic rule is recommended when there is no prior knowledge of individual sensitivities and specificities, or the prevalence of the true positive findings in the study population. The optimal sampling is applied to a real-world example in record linkage to evaluate the difference in classification accuracy of two matching algorithms. Copyright © 2013 John Wiley & Sons, Ltd.

  12. Comparative analysis for performance of brown coal combustion in a vortex furnace with improved design

    Science.gov (United States)

    Krasinsky, D. V.

    2016-09-01

    Comparative study of 3D numerical simulation of fluid flow and coal-firing processes was applied for flame combustion of Kansk-Achinsk brown coal in a vortex furnace of improved design with bottom injection of secondary air. The analysis of engineering performance of this furnace was carried out for several operational modes as a function of coal grinding fineness and coal input rate. The preferable operational regime for furnace was found.

  13. Performance of swarm based optimization techniques for designing digital FIR filter: A comparative study

    Directory of Open Access Journals (Sweden)

    I. Sharma

    2016-09-01

    Full Text Available In this paper, a linear phase FIR filter is designed through recently proposed nature inspired optimization algorithm known as Cuckoo search (CS. A comparative study of Cuckoo search (CS, particle swarm optimization (PSO and artificial bee colony (ABC nature inspired optimization methods in the field of linear phase FIR filter design is also presented. For this purpose, an improved L1 weighted error function is formulated in frequency domain, and minimized through CS, PSO and ABC respectively. The error or objective function has a controlling parameter wt which controls the amount of ripple in the desired band of frequency. The performance of FIR filter is examined through three key parameters; Maximum Pass Band Ripple (MPR, Maximum Stopband Ripple (MSR and Stopband Attenuation (As. Comparative study and the simulation results reveal that the designed filter with CS gives better performance in terms of Maximum Stopband Ripple (MSR, and Stopband Attenuation (As for low order filter design, and for higher order it also gives better performance in term of Maximum Passband Ripple (MPR. Superiority of the proposed technique is also shown through comparison with other recently proposed methods.

  14. Active noise control in fuselage design

    NARCIS (Netherlands)

    Krakers, L.A.; Tooren, M.J.L. van; Beukers, A.; Berkhof, A.P.; Goeje, M.P. de

    2003-01-01

    To achieve comfortable noise levels inside the passenger cabin, sound damping measures have to be taken to improve the sound insulation properties of the bare airframe. Usually the sound insulation requirements of a passenger cabin are met after the mechanical design of the fuselage structure is alr

  15. Insights into Airframe Aerodynamics and Rotor-on-Wing Interactions from a 0.25-Scale Tiltrotor Wind Tunnel Model

    Science.gov (United States)

    Young, L. A.; Lillie, D.; McCluer, M.; Yamauchi, G. K.; Derby, M. R.

    2001-01-01

    A recent experimental investigation into tiltrotor aerodynamics and acoustics has resulted in the acquisition of a set of data related to tiltrotor airframe aerodynamics and rotor and wing interactional aerodynamics. This work was conducted in the National Full-scale Aerodynamics Complex's (NFAC) 40-by-80 Foot Wind Tunnel, at NASA Ames Research Center, on the Full-Span Tilt Rotor Aeroacoustic Model (TRAM). The full-span TRAM wind tunnel test stand is nominally based on a quarter-scale representation of the V-22 aircraft. The data acquired will enable the refinement of analytical tools for the prediction of tiltrotor aeromechanics and aeroacoustics.

  16. Design of a Hysteresis Comparator%一种滞回比较器设计

    Institute of Scientific and Technical Information of China (English)

    薛腾飞; 朱江; 乔明

    2015-01-01

    比较器广泛应用于模拟信号到数字信号的转换过程中,在模-数转换过程中,对输入进行采样后的信号通过比较器以决定模拟信号的数字量。滞回比较器也叫迟滞比较器,以其优越的抗噪声能力在比较器中占有重要地位。描述一种滞回比较器,使用少量元件节省成本,滞回电压阈值设计灵活,同时用P管作差分输入管,有较高的共模输入范围,转换速率快。使用0.18μm CMOS工艺分别对转折点压差为200 mV的设计进行仿真,仿真结果与设计预期相符合。%Comparator is widely used in conversion of analog signal to digital signal. In analog-to-digital conversion, the input signal is sampled by comparator to determined the output digital signal. Hysteresis comparator also called sluggish comparator with superior anti noise ability plays an important role in comparator. The paper describes a hysteresis comparator with simple structure and hysteresis voltage threshold design lfexibility. At the same time PMOS are the differential input transistors and the comparator has high common mode input range and large slew rate. The design with turning point of voltage difference 200 mV is simulated with 0.18 μm CMOS process and the results are accord with the desired outcome.

  17. Tension and Bending Testing of an Integral T-Cap for Stitched Composite Airframe Joints

    Science.gov (United States)

    Lovejoy, Andrew E.; Leone, Frank A., Jr.

    2016-01-01

    The Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) is a structural concept that was developed by The Boeing Company to address the complex structural design aspects associated with a pressurized hybrid wing body aircraft configuration. An important design feature required for assembly is the integrally stitched T-cap, which provides connectivity of the corner (orthogonal) joint between adjacent panels. A series of tests were conducted on T-cap test articles, with and without a rod stiffener penetrating the T-cap web, under tension (pull-off) and bending loads. Three designs were tested, including the baseline design used in large-scale test articles. The baseline had only the manufacturing stitch row adjacent to the fillet at the base of the T-cap web. Two new designs added stitching rows to the T-cap web at either 0.5- or 1.0-inch spacing along the height of the web. Testing was conducted at NASA Langley Research Center to determine the behavior of the T-cap region resulting from the applied loading. Results show that stitching arrests the initial delamination failures so that the maximum strength capability exceeds the load at which the initial delaminations develop. However, it was seen that the added web stitching had very little effect on the initial delamination failure load, but actually decreased the initial delamination failure load for tension loading of test articles without a stiffener passing through the web. Additionally, the added web stitching only increased the maximum load capability by between 1% and 12.5%. The presence of the stiffener, however, did increase the initial and maximum loads for both tension and bending loading as compared to the stringerless baseline design. Based on the results of the few samples tested, the additional stitching in the T-cap web showed little advantage over the baseline design in terms of structural failure at the T-cap web/skin junction for the current test articles.

  18. Comparative Analysis of Postmodern Design for Information Technology in Education in Relation to Modernism

    Directory of Open Access Journals (Sweden)

    Saeid Zarghami Hamrah

    2012-01-01

    Full Text Available Problem statement: The purpose of present study is a comparative analysis of the philosophical bases of postmodernism in relation to modernism and suggesting the necessities of each base in the designing information technology in education. Approach: The research method for the present study was comparative analysis. Results: The first base was rejection of objective view toward the universe and accepting the “pre-objective universe”. In this regard, it was suggested that information technology should be considered in relation to and as a component of life. The second base was doing away with totality. The necessity of this base was in the rejection of universal approaches and designing for specific situations. The third base was uncertainty. Regarding this base, it was suggested that the educational software provide a text in which the learner confront subjects for questioning and interpreting. The forth base was focusing on the complexities of the phenomena. In this ground, it was especially necessary for the design to be integrational. Conclusion/Recommendations: It seems that postmodernism view has been able to provide the possibility of recreating information technology in education through going beyond the basic assumptions of modernism. At last and in order to escape the metanarrative view toward postmodern ideas, we cannot regard the recommended solutions by postmodernists as the definite, final and general solution for educational issues of present and past times. But, we can look at them for further illumination of technological education condition of the present time.

  19. Flexible designs for phase II comparative clinical trials involving two response variables.

    Science.gov (United States)

    Bersimis, S; Sachlas, A; Papaioannou, T

    2015-01-30

    The aim of phase II clinical trials is to determine whether an experimental treatment is sufficiently promising and safe to justify further testing. The need for reduced sample size arises naturally in phase II clinical trials owing to both technical and ethical reasons, motivating a significant part of research in the field during recent years, while another significant part of the research effort is aimed at more complex therapeutic schemes that demand the consideration of multiple endpoints to make decisions. In this paper, our attention is restricted to phase II clinical trials in which two treatments are compared with respect to two dependent dichotomous responses proposing some flexible designs. These designs permit the researcher to terminate the clinical trial when high rates of favorable or unfavorable outcomes are observed early enough requiring in this way a small number of patients. From the mathematical point of view, the proposed designs are defined on bivariate sequences of multi-state trials, and the corresponding stopping rules are based on various distributions related to the waiting time until a certain number of events appear in these sequences. The exact distributions of interest, under a unified framework, are studied using the Markov chain embedding technique, which appears to be very useful in clinical trials for the sample size determination. Tables of expected sample size and power are presented. The numerical illustration showed a very good performance for these new designs.

  20. A Comparative Study of Ultra-Low Voltage Digital Circuit Design

    Directory of Open Access Journals (Sweden)

    Aaron Arthurs

    2012-07-01

    Full Text Available Ultra-low voltage digital circuit design is an active research area, especially for portable applications such as wearable electronics, intelligent remote sensors, implantable medical devices, and energy-harvesting systems. Due to their application scenarios and circuit components, two major goals for these systems are minimizing energy consumption and improving compatibility with low-voltage power supplies and analog components. The most effective solution to achieve these goals is to reduce the supply voltage, which,however, raises the issue of operability. At ultra-low supply voltages, the integrity of digital signals degrades dramatically due to the indifference between active and leakage currents. In addition, the system timing becomes more unpredictable as the impact of process and supply voltage variations being more significant at lower voltages. This paper presents a comparative study among three techniques for designing digital circuits operating at ultra-low voltages, i.e., Schmitt-triggered gate structure, delayinsensitive asynchronous logic, and Fully-Depleted Silicon-on-Insulator technology. Results show that despite the tradeoffs, all eight combinations of these techniques are viable for designing ultra-low voltage circuits. For a given application, the optimum circuit design can be selected from these combinations based on the lowest voltage, the dynamic range, the power budget, the performance requirement, and the available semiconductor process node.

  1. A Comparative Study of Ultra-Low Voltage Digital Circuit Design

    Directory of Open Access Journals (Sweden)

    Aaron Arthurs,

    2012-06-01

    Full Text Available Ultra-low voltage digital circuit design is an active research area, especially for portable applications such as wearable electronics, intelligent remote sensors, implantable medical devices, and energy-harvesting systems. Due to their application scenarios and circuit components, two major goals for these systems are minimizing energy consumption and improving compatibility with low-voltage power supplies and analog components. The most effective solution to achieve these goals is to reduce the supply voltage, which,however, raises the issue of operability. At ultra-low supply voltages, the integrity of digital signals degrades dramatically due to the indifference between active and leakage currents. In addition, the system timing becomes more unpredictable as the impact of process and supply voltage variations being more significant at lower voltages. This paper presents a comparative study among three techniques for designing digital circuits operating at ultra-low voltages, i.e., Schmitt-triggered gate structure, delay insensitive asynchronous logic, and Fully-Depleted Silicon-on-Insulator technology. Results show that despite the trade offs, all eight combinations of these techniques are viable for designing ultra-low voltage circuits. For a given application, the optimum circuit design can be selected from these combinations based on the lowest voltage, the dynamic range, the power budget, the performance requirement, and the available semiconductor process node.

  2. GaAs multibit delta-sigma A/D converters based upon a new comparator design

    Energy Technology Data Exchange (ETDEWEB)

    Hickling, R.M.; Yagi, M.N.; Salman, H.H. [TechnoConcepts, Inc., Newbury Park, CA (United States)

    1995-12-31

    In this paper, the design of multibit delta-sigma converters based upon a new comparator bank structure is described. The comparator bank approach (patent pending) eliminates the need for comparator threshold terminals, allowing each of the individual latched comparators to operate upon the same differential input signal. This new comparator design was incorporated into a complete four-bit delta-sigma modulator which was fabricated on a 0.6{mu}m GaAs MESFET process.

  3. The Design of the IGE Evaluation Project Phase IV Comparative Studies. Comparative Study of Phase IV IGE Evaluation Project. Phase IV, Project Paper 80-2.

    Science.gov (United States)

    Romberg, Thomas A.; And Others

    This paper outlines the design of two Comparative Studies of Phase IV of the Individually Guided Education (IGE) Evaluation Project. More than 2,000 elementary schools in 25 states use the IGE system. The Evaluation Project was designed to gain a comprehensive view of the system's operation and effectiveness. Phase IV investigated pupil outcomes,…

  4. Comparative Analysis of ALU Implementation with RCA and Sklansky Adders In ASIC Design Flow

    Directory of Open Access Journals (Sweden)

    Abdul Rehman Buzdar

    2016-07-01

    Full Text Available An Arithmetic Logic Unit (ALU is the heart of every central processing unit (CPU which performs basic operations like addition, subtraction, multiplication, division and bitwise logic operations on binary numbers. This paper deals with implementation of a basic ALU unit using two different types of adder circuits, a ripple carry adder and a sklansky type adder. The ALU is designed using application specific integrated circuit (ASIC platform where VHDL hardware description language and standard cells are used. The target process technology is 130nm CMOS from the foundry ST Microelectronics. The Cadence EDA tools are used for the ASIC implementation. A comparative analysis is provided for the two ALU circuits designed in terms of area, power and timing requirements.

  5. Comparing modelling techniques when designing VPH gratings for BigBOSS

    Science.gov (United States)

    Poppett, Claire; Edelstein, Jerry; Lampton, Michael; Jelinsky, Patrick; Arns, James

    2012-09-01

    BigBOSS is a Stage IV Dark Energy instrument based on the Baryon Acoustic Oscillations (BAO) and Red Shift Distortions (RSD) techniques using spectroscopic data of 20 million ELG and LRG galaxies at 0.5VPH) gratings have been identified as a key technology which will enable the efficiency requirement to be met, however it is important to be able to accurately predict their performance. In this paper we quantitatively compare different modelling techniques in order to assess the parameter space over which they are more capable of accurately predicting measured performance. Finally we present baseline parameters for grating designs that are most suitable for the BigBOSS instrument.

  6. COMPARING PUMA ROBOT ARM WITH THE HUMAN ARM MOVEMENTS; AN ALTERNATIVE ROBOTIC ARM SHOULDER DESIGN

    OpenAIRE

    Mustafa BOZDEMİR; ADIGÜZEL, Esat

    1999-01-01

    Using the robotic arms instead of human power becomes increasingly widespread nowadays. Widening of the robotic arms usage field is parallel to improvement of movement capability of it. In this study PUMA Robotic Arm System that is a developed system of the robotic arms was compared with a human arm due to movement. A new joint was added to PUMA Robotic Arm System to have the movements similar to the human shoulder joint. Thus, a shoulder was designed that can make movements through the sides...

  7. Shear Bond Strength of Ceramic Brackets with Different Base Designs: Comparative In-vitro Study

    Science.gov (United States)

    Ansari, Mohd. Younus; Agarwal, Deepak K; Bhattacharya, Preeti; Ansar, Juhi; Bhandari, Ravi

    2016-01-01

    Introduction Knowledge about the Shear Bond Strength (SBS) of ceramic brackets with different base design is essential as it affects bond strength to enamel. Aim The aim of the present study was to evaluate and compare the effect of base designs of different ceramic brackets on SBS, and to determine the fracture site after debonding. Materials and Methods Four groups of ceramic brackets and one group of metal brackets with different base designs were used. Adhesive precoated base of Clarity Advanced (APC Flash-free) (Unitek/3M, Monrovia, California), microcrystalline base of Clarity Advanced (Unitek/3M, Monrovia, California), polymer mesh base of InVu (TP Orthodontics, Inc., La Porte, IN, United States), patented bead ball base of Inspire Ice (Ormco, Glendora, California), and a mechanical mesh base of Gemini Metal bracket (Unitek/3M, Monrovia, California). Ten brackets of each type were bonded to 50 maxillary premolars with Transbond XT (Unitek/3M). Samples were stored in distilled water at room temperature for 24 hours and subsequently tested in shear mode on a universal testing machine (Model 3382; Instron Corp., Canton, Massachusetts, USA) at a cross head speed of 1mm/minute with the help of a chisel. The debonded interface was recorded and analyzed to determine the predominant bond failure site under an optical microscope (Stereomicroscope) at 10X magnification. One way analysis of variance (ANOVA) was used to compare SBS. Tukey’s significant differences tests were used for post-hoc comparisons. The Adhesive Remnant Index (ARI) scores were compared by chi-square test. Results Mean SBS of microcrystalline base (27.26±1.73), was the highest followed by bead ball base (23.45±5.09), adhesive precoated base (20.13±5.20), polymer mesh base (17.54±1.91), and mechanical mesh base (17.50±2.41) the least. Comparing the frequency (%) of ARI Score among the groups, chi-square test showed significantly different ARI scores among the groups (χ2 = 34.07, p<0

  8. Electrically Small Resonators for Planar Metamaterial, Microwave Circuit and Antenna Design: A Comparative Analysis

    Directory of Open Access Journals (Sweden)

    Miguel Durán-Sindreu

    2012-04-01

    Full Text Available Planar metamaterials and many microwave circuits and antennas are designed by means of resonators with dimensions much smaller than the wavelength at their resonance frequency. There are many types of such electrically small resonators, and the main purpose of this paper is to compare them as building blocks for the implementation of microwave components. Aspects such as resonator size, bandwidth, their circuit models when they are coupled to transmission lines (as is usually required, as well as key applications, will be considered.

  9. Multidimensional Aptitude Battery-Second Edition Intelligence Testing of Remotely Piloted Aircraft Training Candidates Compared with Manned Airframe Training Candidates

    Science.gov (United States)

    2015-03-01

    schizophrenia, attention deficit hyperactivity disorder , and autism spectrum disorders ) and not on very high functioning populations such as aviators...pilots and to the development of a U.S. Air Force (USAF) RPA pilot career field. Effective recruitment into this new career field is critical to...high levels of intelligence, dexterity, visual-spatial abilities, memory, attention /concentration, psychomotor reaction time, as well as speed and

  10. Comparing Acoustic Tag Attachments Designed for Mobile Tracking of Hatchling Sea Turtles

    Directory of Open Access Journals (Sweden)

    Aimee L. Hoover

    2017-07-01

    Full Text Available The poorly understood movements of sea turtles during the “lost years” of their early life history have been characterized as a “passive drifter” stage. Biologging technology allows us to study patterns of dispersal, but the small body size of young life stages requires particular consideration that such tagging does not significantly impede animal movements. We tested the effect of instrument attachment methods for mobile acoustic tracking of hatchling sea turtles, including a design that would be suitable for leatherback turtles (Dermochelys coriacea. We obtained 8-week-old hatchery-reared green sea turtles (Chelonia mydas (n = 12 individuals and examined the effect of attaching Vemco V5 acoustic tags. Each animal's swim speed, swimming depth, and stroke frequency were determined under three scenarios: control, direct Velcro® attachment to the carapace, and harness attachment, to determine if there was a significant difference amongst treatments. Turtle swimming speed was significantly slower during the middle period of the trial for the harness attachment compared with the control. No significant change in swim speed was observed when the tag was attached directly with Velcro®, and no significant change in dive depth was observed for either treatment compared to the control. Stroke frequency was significantly greater compared to the control at the end of the trial for the Velcro® attachment only, although there was no corresponding increase in swimming speed. This information can be used to design effective approaches for actively tracking free-ranging hatchling sea turtles to understand dispersal and survival of these vulnerable marine species.

  11. Experimental analysis of oligonucleotide microarray design criteria to detect deletions by comparative genomic hybridization

    Directory of Open Access Journals (Sweden)

    Moerman Donald G

    2008-10-01

    Full Text Available Abstract Background Microarray comparative genomic hybridization (CGH is currently one of the most powerful techniques to measure DNA copy number in large genomes. In humans, microarray CGH is widely used to assess copy number variants in healthy individuals and copy number aberrations associated with various diseases, syndromes and disease susceptibility. In model organisms such as Caenorhabditis elegans (C. elegans the technique has been applied to detect mutations, primarily deletions, in strains of interest. Although various constraints on oligonucleotide properties have been suggested to minimize non-specific hybridization and improve the data quality, there have been few experimental validations for CGH experiments. For genomic regions where strict design filters would limit the coverage it would also be useful to quantify the expected loss in data quality associated with relaxed design criteria. Results We have quantified the effects of filtering various oligonucleotide properties by measuring the resolving power for detecting deletions in the human and C. elegans genomes using NimbleGen microarrays. Approximately twice as many oligonucleotides are typically required to be affected by a deletion in human DNA samples in order to achieve the same statistical confidence as one would observe for a deletion in C. elegans. Surprisingly, the ability to detect deletions strongly depends on the oligonucleotide 15-mer count, which is defined as the sum of the genomic frequency of all the constituent 15-mers within the oligonucleotide. A similarity level above 80% to non-target sequences over the length of the probe produces significant cross-hybridization. We recommend the use of a fairly large melting temperature window of up to 10°C, the elimination of repeat sequences, the elimination of homopolymers longer than 5 nucleotides, and a threshold of -1 kcal/mol on the oligonucleotide self-folding energy. We observed very little difference in data

  12. Composting on Mars or the Moon: I. Comparative evaluation of process design alternatives

    Science.gov (United States)

    Finstein, M. S.; Strom, P. F.; Hogan, J. A.; Cowan, R. M.; Janes, H. W. (Principal Investigator)

    1999-01-01

    As a candidate technology for treating solid wastes and recovering resources in bioregenerative Advanced Life Support, composting potentially offers such advantages as compactness, low mass, near ambient reactor temperatures and pressures, reliability, flexibility, simplicity, and forgiveness of operational error or neglect. Importantly, the interactions among the physical, chemical, and biological factors that govern composting system behavior are well understood. This article comparatively evaluates five Generic Systems that describe the basic alternatives to composting facility design and control. These are: 1) passive aeration; 2) passive aeration abetted by mechanical agitation; 3) forced aeration--O2 feedback control; 4) forced aeration--temperature feedback control; 5) forced aeration--integrated O2 and temperature feedback control. Each of the five has a distinctive pattern of behavior and process performance characteristics. Only Systems 4 and 5 are judged to be viable candidates for ALS on alien worlds, though which is better suited in this application is yet to be determined.

  13. Fuzzy Controller Design Using Evolutionary Techniques for Twin Rotor MIMO System: A Comparative Study

    Directory of Open Access Journals (Sweden)

    H. A. Hashim

    2015-01-01

    Full Text Available This paper presents a comparative study of fuzzy controller design for the twin rotor multi-input multioutput (MIMO system (TRMS considering most promising evolutionary techniques. These are gravitational search algorithm (GSA, particle swarm optimization (PSO, artificial bee colony (ABC, and differential evolution (DE. In this study, the gains of four fuzzy proportional derivative (PD controllers for TRMS have been optimized using the considered techniques. The optimization techniques are developed to identify the optimal control parameters for system stability enhancement, to cancel high nonlinearities in the model, to reduce the coupling effect, and to drive TRMS pitch and yaw angles into the desired tracking trajectory efficiently and accurately. The most effective technique in terms of system response due to different disturbances has been investigated. In this work, it is observed that GSA is the most effective technique in terms of solution quality and convergence speed.

  14. Designing online audiovisual heritage services: an empirical study of two comparable online video services

    Science.gov (United States)

    Ongena, G.; van de Wijngaert, L. A. L.; Huizer, E.

    2013-03-01

    The purpose of this study is to seek input for a new online audiovisual heritage service. In doing so, we assess comparable online video services to gain insights into the motivations and perceptual innovation characteristics of the video services. The research is based on data from a Dutch survey held among 1,939 online video service users. The results show that online video service held overlapping antecedents but does show differences in motivations and in perceived innovation characteristics. Hence, in general, one can state that in comparison, online video services comply with different needs and have differences in perceived innovation characteristics. This implies that one can design online video services for different needs. In addition to scientific implications, the outcomes also provide guidance for practitioners in implementing new online video services.

  15. Design, simulation and comparative analysis of CNT based cascode operational transconductance amplifiers

    Science.gov (United States)

    Nizamuddin, M.; Loan, Sajad A.; Alamoud, Abdul R.; Abbassi, Shuja A.

    2015-10-01

    In this work, design and calibrated simulation of carbon nanotube field effect transistor (CNTFET)-based cascode operational transconductance amplifiers (COTA) have been performed. Three structures of CNTFET-based COTAs have been designed using HSPICE and have been compared with the conventional CMOS-based COTAs. The proposed COTAs include one using pure CNTFETs and two others that employ CNTFETs, as well as the conventional MOSFETs. The simulation study has revealed that the CNTFET-based COTAs have significantly outperformed the conventional MOSFET-based COTAs. A significant increase in dc gain, output resistance and slew rate of 81.4%, 25% and 13.2%, respectively, have been achieved in the proposed pure CNT-based COTA in comparison to the conventional CMOS-based COTA. The power consumption in the pure CNT-COTA is 324 times less in comparison to the conventional CMOS-COTA. Further, the phase margin (PM), gain margin (GM), common mode and power supply rejection ratios have been significantly increased in the proposed CNT-based COTAs in comparison to the conventional CMOS-based COTAs. Furthermore, to see the advantage of cascoding, the proposed CNT-based cascode OTAs have been compared with the CNT-based OTAs. It has been observed that by incorporating the concept of cascode in the CNTFET-based OTAs, significant increases in gain (12.5%) and output resistance (13.07%) have been achieved. The performance of the proposed COTAs has been further observed by changing the number of CNTs (N), CNT pitch (S) and CNT diameter (DCNT) in the CNTFETs used. It has been observed that the performance of the proposed COTAs can be significantly improved by using optimum values of N, S and DCNT.

  16. Design of e-books: readers’ expectations in a comparative perspective

    Directory of Open Access Journals (Sweden)

    Josipa Selthofer

    2014-03-01

    Full Text Available The aim of the paper is to compare graphic elements used for the design of printed and electronic books. The paper focuses on four main graphic elements: book cover, typography, colour and image. Ten books published in printed and electronic form in Croatia between 2010 and 2012 were used as a research sample. The research methods used are visual content analysis and interviews. The research results indicate that e-books imitate the graphic design of a printed book in many aspects. The graphic elements of an e-book highly depend on the features of e-formats and on e-readers. The main advantages of an e-book are that they are searchable, adaptable, easily linked to other digital documents, transportable, easily accessible and durable. Still, in the second phase of the research, the majority of the interviewed participants stated that reading of an e-book was something new to them. They prefer the interaction with a printed book and its visual appearance.

  17. Carborane Clusters in Computational Drug Design: A Comparative Docking Evaluation Using Autodock, Flexx, Glide and Surflex#

    Science.gov (United States)

    Tiwari, Rohit; Mahasenan, Kiran; Pavlovicz, Ryan; Li, Chenglong; Tjarks, Werner

    2009-01-01

    Compounds containing boron atoms play increasingly important roles in the therapy and diagnosis of various diseases, particularly cancer. However, computational drug design of boron-containing therapeutics and diagnostics is hampered by the fact that many software packages used for this purpose lack parameters for all or part of the various types of boron atoms. In the present paper, we describe simple and efficient strategies to overcome this problem, which are based on the replacement of the boron atom types with carbon atom types. The developed methods were validated by docking closo- and nido-carboranyl antifolates into the active site of a human dihydrofolate reductase (hDHFR) using AutoDock, Glide, FlexX, and Surflex and comparing the obtained docking poses with the poses of their counterparts in the original hDHFR-carboranyl antifolate crystal structures. Under optimized conditions, AutoDock and Glide were equally good in docking of the closo-carboranyl antifolates followed by Surflex and FlexX whereas Autodock, Glide, and Surflex proved to be comparably efficient in the docking of nido-carboranyl antifolates followed by FlexX. Differences in geometries and partial atom charges in the structures of the carboranyl antifolates resulting from different data sources and/or optimization methods did not impact the docking performances of AutoDock or Glide significantly. Scoring functions generated by all four programs were in accordance with experimental data. PMID:19449853

  18. Evolution versus "intelligent design": comparing the topology of protein-protein interaction networks to the Internet.

    Science.gov (United States)

    Yang, Q; Siganos, G; Faloutsos, M; Lonardi, S

    2006-01-01

    Recent research efforts have made available genome-wide, high-throughput protein-protein interaction (PPI) maps for several model organisms. This has enabled the systematic analysis of PPI networks, which has become one of the primary challenges for the system biology community. In this study, we attempt to understand better the topological structure of PPI networks by comparing them against man-made communication networks, and more specifically, the Internet. Our comparative study is based on a comprehensive set of graph metrics. Our results exhibit an interesting dichotomy. On the one hand, both networks share several macroscopic properties such as scale-free and small-world properties. On the other hand, the two networks exhibit significant topological differences, such as the cliqueishness of the highest degree nodes. We attribute these differences to the distinct design principles and constraints that both networks are assumed to satisfy. We speculate that the evolutionary constraints that favor the survivability and diversification are behind the building process of PPI networks, whereas the leading force in shaping the Internet topology is a decentralized optimization process geared towards efficient node communication.

  19. Efficiency versus Equality: Comparing Design Options for Indirect Emissions Accounting in the Korean Emissions Trading Scheme

    Directory of Open Access Journals (Sweden)

    Inha Oh

    2015-11-01

    Full Text Available The Korean emissions trading scheme (ETS has one special characteristic that makes it different from other schemes, such as the EU ETS. While the other schemes consider only direct emissions from fossil fuels, the Korean ETS also regulates indirect emissions arising from the consumption of electricity. The problem of double counting arises under this setting, in which emissions from the power sector can be accounted for twice, when electricity is produced and consumed. This study aims to compare design options on indirect emissions accounting for the Korean ETS using a computable general equilibrium model. Four scenarios are generated for options accounting for direct and/or indirect emissions and are evaluated in terms of efficiency and equality. The result shows that the ETS operates most efficiently when only direct emissions are considered. However, the option that includes both direct and indirect emissions produces a competent result in terms of equality by spreading the economic burden of emissions reduction among industries. We conclude that this option can be an alternative to meet the key purposes of the Korean ETS.

  20. Evaluations of Design Gardens by Students of Landscape Architecture and Non-design Students: A Comparative Study

    NARCIS (Netherlands)

    Karmanov, D.Y.; Hamel, R.

    2009-01-01

    In our study we explore similarities and differences in the evaluations of 12 design gardens by students of landscape architecture and psychology students. The participants in our study visited the gardens and judged them on location. We used a questionnaire to assess similarities and differences in

  1. Evaluations of design gardens by students of landscape architecture and non-design students: a comparative study

    NARCIS (Netherlands)

    Karmanov, D.; Hamel, R.

    2009-01-01

    In our study we explore similarities and differences in the evaluations of 12 design gardens by students of landscape architecture and psychology students. The participants in our study visited the gardens and judged them on location. We used a questionnaire to assess similarities and differences in

  2. Comparative effectiveness of colony-stimulating factors in febrile neutropenia prophylaxis: how results are affected by research design.

    Science.gov (United States)

    Henk, Henry J; Li, Xiaoyan; Becker, Laura K; Xu, Hairong; Gong, Qi; Deeter, Robert G; Barron, Richard L

    2015-01-01

    To examine the impact of research design on results in two published comparative effectiveness studies. Guidelines for comparative effectiveness research have recommended incorporating disease process in study design. Based on the recommendations, we develop a checklist of considerations and apply the checklist in review of two published studies on comparative effectiveness of colony-stimulating factors. Both studies used similar administrative claims data, but different methods, which resulted in directionally different estimates. Major design differences between the two studies include: whether the timing of intervention in disease process was identified and whether study cohort and outcome assessment period were defined based on this temporal relationship. Disease process and timing of intervention should be incorporated into the design of comparative effectiveness studies.

  3. Characterizing Design Cognition of High School Students: Initial Analyses Comparing Those with and without Pre-Engineering Experiences

    Science.gov (United States)

    Wells, John; Lammi, Matthew; Gero, John; Grubbs, Michael E.; Paretti, Marie; Williams, Christopher

    2016-01-01

    Reported in this article are initial results from of a longitudinal study to characterize the design cognition and cognitive design styles of high school students with and without pre-engineering course experience over a 2-year period, and to compare them with undergraduate engineering students. The research followed a verbal protocol analysis…

  4. Testing and Analysis of a Composite Non-Cylindrical Aircraft Fuselage Structure. Part 1; Ultimate Design Loads

    Science.gov (United States)

    Przekop, Adam; Jegley, Dawn C.; Lovejoy, Andrew E.; Rouse, Marshall; Wu, Hsi-Yung T.

    2016-01-01

    The Environmentally Responsible Aviation Project aimed to develop aircraft technologies enabling significant fuel burn and community noise reductions. Small incremental changes to the conventional metallic alloy-based 'tube and wing' configuration were not sufficient to achieve the desired metrics. One airframe concept identified by the project as having the potential to dramatically improve aircraft performance was a composite-based hybrid wing body configuration. Such a concept, however, presented inherent challenges stemming from, among other factors, the necessity to transfer wing loads through the entire center fuselage section which accommodates a pressurized cabin confined by flat or nearly flat panels. This paper discusses finite element analysis and testing of a large-scale hybrid wing body center section structure developed and constructed to demonstrate that the Pultruded Rod Stitched Efficient Unitized Structure concept can meet these challenging demands of the next generation airframes. Part I of the paper considers the five most critical load conditions, which are internal pressure only and positive and negative g-loads with and without internal pressure. Analysis results are compared with measurements acquired during testing. Performance of the test article is found to be closely aligned with predictions and, consequently, able to support the hybrid wing body design loads in pristine and barely visible impact damage conditions.

  5. A Randomized Trial Comparing Classical Participatory Design to VandAID, an Interactive CrowdSourcing Platform to Facilitate User-Centered Design.

    Science.gov (United States)

    Dufendach, Kevin R; Koch, Sabine; Unertl, Kim M; Lehmann, Christoph U

    2017-04-28

    Early involvement of stakeholders in the design of medical software is particularly important due to the need to incorporate complex knowledge and actions associated with clinical work. Standard user-centered design methods include focus groups and participatory design sessions with individual stakeholders, which generally limit user involvement to a small number of individuals due to the significant time investments from designers and end users. The goal of this project was to reduce the effort for end users to participate in co-design of a software user interface by developing an interactive web-based crowdsourcing platform. In a randomized trial, we compared a new web-based crowdsourcing platform to standard participatory design sessions. We developed an interactive, modular platform that allows responsive remote customization and design feedback on a visual user interface based on user preferences. The responsive canvas is a dynamic HTML template that responds in real time to user preference selections. Upon completion, the design team can view the user's interface creations through an administrator portal and download the structured selections through a REDCap interface. We have created a software platform that allows users to customize a user interface and see the results of that customization in real time, receiving immediate feedback on the impact of their design choices. Neonatal clinicians used the new platform to successfully design and customize a neonatal handoff tool. They received no specific instruction and yet were able to use the software easily and reported high usability. VandAID, a new web-based crowdsourcing platform, can involve multiple users in user-centered design simultaneously and provides means of obtaining design feedback remotely. The software can provide design feedback at any stage in the design process, but it will be of greatest utility for specifying user requirements and evaluating iterative designs with multiple options.

  6. Design of Full-Band and Low-Pass FIR Differentiators: A Comparative Study

    Science.gov (United States)

    Mekhnache, C.; Ferdi, Y.; Taleb-Ahmed, A.

    2008-06-01

    Digital differentiators are useful in many fields of sciences and engineering. They can be designed using two approaches, namely, FIR filters design and FIR filters design. This paper is concerned by the first one in which great interest in the design of digital differentiators has encouraged the development of various design methods. The widely used methods for FIR differentiators are those based on criteria L1, L2, L∞ and that based on Taylor series. A comparison between these methods is carried out in terms of approximation accuracy and computational complexity. Numeric examples are presented to illustrate the performance of each method. It was found that the design results obtained by least squares method for fullband and low-pass differentiators are better than the other ones.

  7. Optimizing trial design in pharmacogenetics research: comparing a fixed parallel group, group sequential, and adaptive selection design on sample size requirements.

    Science.gov (United States)

    Boessen, Ruud; van der Baan, Frederieke; Groenwold, Rolf; Egberts, Antoine; Klungel, Olaf; Grobbee, Diederick; Knol, Mirjam; Roes, Kit

    2013-01-01

    Two-stage clinical trial designs may be efficient in pharmacogenetics research when there is some but inconclusive evidence of effect modification by a genomic marker. Two-stage designs allow to stop early for efficacy or futility and can offer the additional opportunity to enrich the study population to a specific patient subgroup after an interim analysis. This study compared sample size requirements for fixed parallel group, group sequential, and adaptive selection designs with equal overall power and control of the family-wise type I error rate. The designs were evaluated across scenarios that defined the effect sizes in the marker positive and marker negative subgroups and the prevalence of marker positive patients in the overall study population. Effect sizes were chosen to reflect realistic planning scenarios, where at least some effect is present in the marker negative subgroup. In addition, scenarios were considered in which the assumed 'true' subgroup effects (i.e., the postulated effects) differed from those hypothesized at the planning stage. As expected, both two-stage designs generally required fewer patients than a fixed parallel group design, and the advantage increased as the difference between subgroups increased. The adaptive selection design added little further reduction in sample size, as compared with the group sequential design, when the postulated effect sizes were equal to those hypothesized at the planning stage. However, when the postulated effects deviated strongly in favor of enrichment, the comparative advantage of the adaptive selection design increased, which precisely reflects the adaptive nature of the design. Copyright © 2013 John Wiley & Sons, Ltd.

  8. Design and comparative study of discrete and module-based IGBT power converters

    Indian Academy of Sciences (India)

    D VENKATRAMANAN; ANIL KUMAR ADAPA; VINOD JOHN

    2017-08-01

    This paper discusses concepts of a 20 kVA power converter design and key differences between discrete IGBT and module-based design approaches. Module-based power converters have been typically employed in academic and research institutes for power levels of 10 kVA and more. However, with advancement in IGBT technologies and the growing need to minimize system size and weight, designs based on discrete devices are now an attractive alternative for such power levels. A simple procedure is presented for power converter design that includes power loss evaluation, heat-sink thermal characterization, thermal model of overall system and sizing of DC link capacitor. Using the same, a state-of-the-art discrete device and modulebased power converters are designed. A comparison is subsequently made, where it is shown that discrete approach yields a compact and economic design up to a power level of 20 kVA. A key objective of this work is to lay emphasis on laboratory design of power converters. This enables a graduate level student to build a converter from start and in the process gain insights into the underlying engineering design aspects.

  9. Analyzing Regression-Discontinuity Designs with Multiple Assignment Variables: A Comparative Study of Four Estimation Methods

    Science.gov (United States)

    Wong, Vivian C.; Steiner, Peter M.; Cook, Thomas D.

    2013-01-01

    In a traditional regression-discontinuity design (RDD), units are assigned to treatment on the basis of a cutoff score and a continuous assignment variable. The treatment effect is measured at a single cutoff location along the assignment variable. This article introduces the multivariate regression-discontinuity design (MRDD), where multiple…

  10. Design of high speed and low offset dynamic latch comparator in 0.18 µm CMOS process.

    Science.gov (United States)

    Rahman, Labonnah Farzana; Reaz, Mamun Bin Ibne; Yin, Chia Chieu; Ali, Mohammad Alauddin Mohammad; Marufuzzaman, Mohammad

    2014-01-01

    The cross-coupled circuit mechanism based dynamic latch comparator is presented in this research. The comparator is designed using differential input stages with regenerative S-R latch to achieve lower offset, lower power, higher speed and higher resolution. In order to decrease circuit complexity, a comparator should maintain power, speed, resolution and offset-voltage properly. Simulations show that this novel dynamic latch comparator designed in 0.18 µm CMOS technology achieves 3.44 mV resolution with 8 bit precision at a frequency of 50 MHz while dissipating 158.5 µW from 1.8 V supply and 88.05 µA average current. Moreover, the proposed design propagates as fast as 4.2 nS with energy efficiency of 0.7 fJ/conversion-step. Additionally, the core circuit layout only occupies 0.008 mm2.

  11. Design tools in practice. Comparative evaluation; Auslegungshilfen in der Praxis. Ein Vergleich

    Energy Technology Data Exchange (ETDEWEB)

    Weinreich, Bernhard [Solarschmiede GmbH, Muenchen (Germany); Zehner, Mike [Solarschmiede GmbH, Muenchen (Germany); Hochschule Muenchen (Germany). Labor fuer Solartechnik

    2009-10-01

    Modern design tools can calculate most anything, but do they permit intuitive access? SW and W experts Bernhard Weinreich and Mike Zehner tested the practical handling of the most popular tools. (orig.)

  12. Informing Healthcare Waiting Area Design Using Transparency Attributes: A Comparative Preference Study.

    Science.gov (United States)

    Jiang, Shan; Powers, Matthew; Allison, David; Vincent, Ellen

    2017-07-01

    This study aimed to explore people's visual preference for waiting areas in general hospital environments designed with transparency attributes that fully integrate nature. Waiting can be a tedious and frustrating experience among people seeking healthcare treatments and negatively affect their perception of the quality of care. Positive distractions and supportive designs have gained increasing attraction to improve people's waiting experience. Nature, which has shown therapeutic effects according to a growing amount of evidence, could be a distinguished positive distraction in waiting areas. Additionally, the theory of transparency was operationalized to indicate a spatial continuity between the external nature and the built interiors in general healthcare waiting area design. A survey method was adopted in the study. Twenty-one images of general healthcare waiting areas depicting three design typologies were preselected following a strict procedure, including designs with (a) no window views, (b) limited window views to nature, and (c) transparent spaces with maximum natural views. Ninety-five student participants rated the images based on their visual preference using a Likert-type scale. The results showed that transparent waiting areas were significantly preferred. A significant positive relationship existed between the level of transparency and people's preference scores. The factor analysis indicated additional supportive features that may affect people's preferences, including daylight, perceived warmth, noninstitutional furniture arrangement, visual orientation, and the use of natural materials for interior design. However, these tentative results need to be furthered tested with the real patient population as the next step of this study.

  13. Functional outcomes used to compare single radius and multiradius of curvature designs in total knee arthroplasty.

    Science.gov (United States)

    Cook, Laurence E; Klika, Alison K; Szubski, Caleb R; Rosneck, James; Molloy, Robert; Barsoum, Wael K

    2012-07-01

    A recent development to better recreate joint kinematics has been a change from a multiradius (MR) design to a single radius (SR) design. We analyzed 559 primary total knee arthroplasty (TKA) procedures which used either a SR (n = 426 Triathlon; Stryker Orthopaedics, Mahwah, NJ) or MR of curvature knee system (n = 133 Duracon; Stryker Orthopaedics, Mahwah, NJ) (79.3% follow-up; 705 total TKA procedures identified). Patients were administered a modification of the Knee Society score (KSS) (3.9 years average follow-up). The SR design showed improvements over the MR design in pain (p = 0.021), stability (p = 0.002), flexion (p = 0.006), ability to completely straighten the knee (p = 0.025), stair climbing (p = 0.0001), walking (p = 0.0001), use of assistive devices (p = 0.0005), postoperative knee score (p = 0.0005), and postoperative function (p < 0.0001). Analysis of the change in KSS knee (p = 0.002) and function scores (p = 0.002) from preoperative visit to postoperative follow-up favored the SR design as well. These data support the use of SR implants and provide evidence of improved outcomes in terms of function, stability, and pain.

  14. Study to Determine the Impact of Aircrew Anthropometry on Airframe Configuration.

    Science.gov (United States)

    1976-10-31

    are based on monocular vision from the design eye position as defined by WS 33573, MS 33574, and MIL-STD-1333. The design eye position, defined by MIL...kA4 1 NjjTICA: MIES ..PE .R POUN .D R::-ev No. R-4 8 J -~L.1.,J. -E LEE111 Mar 6 A USON T63-A-700 ENGINEI.’ 1 :. ICAO STAL DARD DAY WJILLILY TF -777

  15. Comparative Study of Cross Browser Compatibility as Design Issue in Various Websites

    Directory of Open Access Journals (Sweden)

    Jatinder Manhas

    2015-01-01

    Full Text Available In this current era of information technology websites are very important means of communication. Lot of efforts is required by different institutions / organizations to portray complete information on beautifully designed websites. Websites act as an online agent through which a user can get his work done without physically visiting the organizations. Website design is given with a very critical look by the designer so that it can provide users with all the facilities of the concerned institutions / organizations online. To make websites behavior similar in all the different browsers employed by the different categories of the users, the responsibility of the designer and the concerned institutions / organizations increases manifold. In this research paper author developed an online tool using .NET Framework using C# to study cross browser compatibility as Design issue in various categories of the websites like Job portals, Government, educational, Commercial and Social networking. The automated tool developed by author function on the basis of the different standards prescribed in W3C guidelines document UAAG 2.0 [7] and act like a parser and renders the complete code of the website and produces result on basis of the behavior of the websites in five most popular and widely used Browsers like parameters like Internet Explorer[7,8,9], Chrome, Safari, Fire fox. Each Browser is tested on the basis of the five parameters which are included in the parser are Blinking, Active X control, Website Resolution; image Formats, HTML Tag errors. The results obtained after testing five different categories of websites shows that educational and social networking sites shows least compatibility in multiple browsers where as job portals, commercial and government websites shows 100% compliance to the website design standards recommended by W3C w.r.t browser compatibility of different websites on different browsing platform.

  16. A comparative study of varying fan noise mitigation techniques in relation to sustainable design goals

    Science.gov (United States)

    Overweg, Cornelis; Fullerton, Jeff L.

    2005-04-01

    Green building design promotes effective use of materials and energy, improved indoor environmental quality (IEQ), and enhanced occupant comfort. These ``green'' goals can occasionally conflict with common acoustical approaches used for fan noise control. A design striving for low noise levels from the ventilation system to benefit occupant comfort can inadvertently introduce elements that are contradictory to other green building objectives. For example, typical fan noise control devices introduce higher energy consumption or less beneficial indoor environmental quality. This paper discusses the acoustical, mechanical, environmental, and relative cost impacts of various fan noise control techniques.

  17. Comparative Study Between the Two Experimental Design Approaches Taguchi and Traditional in Presence of Control by Control Interactions

    Directory of Open Access Journals (Sweden)

    Arias-Nava Elías Heriberto

    2015-03-01

    Full Text Available Design of experiments plays an important role in the field of creating and innovating process and products directly in manufacturing and improving areas. There are several areas into designs of experiments; robust design is one of them. Robust parameter design is a principle that emphasize in products creation through a correct selection of values called “control” which make a product robust to the variability by the noise introducing by another factors known as “noise” factors. This article aims for a comparative study between two well-known robust design methodologies, making a special emphasis in the control by control interaction effects over optimal operating conditions. The results showed that Taguchi´s crossed arrays are unable to estimate all significant terms in a model. The optimizations result concludes that the Taguchi´s approach is less efficient than the traditional approach in both; maximization and minimization.

  18. Technology transfer and other public policy implications of multi-national arrangements for the production of commercial airframes

    Science.gov (United States)

    Gellman, A. J.; Price, J. P.

    1978-01-01

    A study to examine the question of technology transfer through international arrangements for production of commercial transport aircraft is presented. The likelihood of such transfer under various representative conditions was determined and an understanding of the economic motivations for, effects of, joint venture arrangements was developed. Relevant public policy implications were also assessed. Multinational consortia with U.S. participation were focused upon because they generate the full range of pertinent public issues (including especially technology transfer), and also because of recognized trends toward such arrangements. An extensive search and analysis of existing literature to identify the key issues, and in-person interviews with executives of U.S. and European commercial airframe producers was reviewed. Distinctions were drawn among product-embodied, process, and management technologies in terms of their relative possibilities of transfer and the significance of such transfer. Also included are observations on related issues such as the implications of U.S. antitrust policy with respect to the formation of consortia and the competitive viability of the U.S. aircraft manufacturing industry.

  19. Applications of numerical optimization methods to helicopter design problems - A survey

    Science.gov (United States)

    Miura, H.

    1985-01-01

    A survey of applications of mathematical programming methods is used to improve the design of helicopters and their components. Applications of multivariable search techniques in the finite dimensional space are considered. Five categories of helicopter design problems are considered: (1) conceptual and preliminary design, (2) rotor-system design, (3) airframe structures design, (4) control system design, and (5) flight trajectory planning. Key technical progress in numerical optimization methods relevant to rotorcraft applications are summarized.

  20. Applications of numerical optimization methods to helicopter design problems: A survey

    Science.gov (United States)

    Miura, H.

    1984-01-01

    A survey of applications of mathematical programming methods is used to improve the design of helicopters and their components. Applications of multivariable search techniques in the finite dimensional space are considered. Five categories of helicopter design problems are considered: (1) conceptual and preliminary design, (2) rotor-system design, (3) airframe structures design, (4) control system design, and (5) flight trajectory planning. Key technical progress in numerical optimization methods relevant to rotorcraft applications are summarized.

  1. Design of a Low Voltage low Power Double tail comparator in 180nm cmos Technology

    Directory of Open Access Journals (Sweden)

    Mr. Deepak Joseph Babu

    2014-09-01

    Full Text Available The need of analog to digital converters with ultra low power, area efficient and high speed is giving more chance to the use of dynamic regenerative comparators to maximize the speed and power efficiency. In this paper, an analysis on the delay and power of the dynamic comparators will be presented and based on the presented analysis, a new dynamic comparator is proposed, in which the conventional double tail comparator is modified for low power and fast operation even in small supply voltages. Here by adding a few transistors, the power consumptions can be reduced drastically. Post–layout simulation using 180nm CMOS technology confirms the analysis results of the proposed dynamic comparator.

  2. Comparative study of high voltage bushing designs suitable for apparatus containing cryogenic helium gas

    Science.gov (United States)

    Rodrigo, H.; Graber, L.; Kwag, D. S.; Crook, D. G.; Trociewitz, B.

    2013-10-01

    The high voltage bushing forms a critical part of any termination on cables, transformers and other power system devices. Cryogenic entities such as superconducting cables or fault current limiters add more complexity to the design of the bushing. Even more complex are bushings designed for superconducting devices which are cooled by high pressure helium gas. When looking for a bushing suitable for dielectric cable tests in a helium gas cryostat no appropriate device could be found that fulfilled the criterion regarding partial discharge inception voltage level. Therefore we decided to design and manufacture a bushing in-house. In the present work we describe the dielectric tests and operational experience on three types of bushings: One was a modified commercially available ceramics feed through which we adopted for our special need. The second bushing was made of an epoxy resin, with an embedded copper squirrel cage arrangement at the flange, extending down about 30 cm into the cold end of the bushing. This feature reduced the electric field on the surface of the bushing to a negligible value. The third bushing was based on a hollow body consisting of glass fiber reinforced polymer and stainless steel filled with liquid nitrogen. The measurements showed that the dielectric quality of all three bushings exceeded the requirements for the intended purpose. The partial discharge (PD) data from these studies will be used for the design and fabrication of a cable termination for a specialized application on board a US Navy ship.

  3. Comparing Understanding of Programming Design Concepts Using Visual Basic and Traditional Basic.

    Science.gov (United States)

    Bishop-Clark, Cathy

    1998-01-01

    A study of 89 computer programming students in two instructional groups found that those using Visual Basic (VB) mastered programming design concepts as well as those using traditional BASIC. Concludes that VB is an excellent choice for a first programming course (high school or university) emphasizing sequence, selection, iteration, variables,…

  4. Teaching an Aerospace Engineering Design Course via Virtual Worlds: A Comparative Assessment of Learning Outcomes

    Science.gov (United States)

    Okutsu, Masataka; DeLaurentis, Daniel; Brophy, Sean; Lambert, Jason

    2013-01-01

    To test the concept of multiuser 3D virtual environments as media to teach semester-long courses, we developed a software prototype called Aeroquest. An aerospace design course--offered to 135 second-year students for university credits in Fall 2009--was divided into two groups: the real-world group attending lectures, physically, in a campus hall…

  5. Analyzing Regression-Discontinuity Designs with Multiple Assignment Variables: A Comparative Study of Four Estimation Methods

    Science.gov (United States)

    Wong, Vivian C.; Steiner, Peter M.; Cook, Thomas D.

    2012-01-01

    In a traditional regression-discontinuity design (RDD), units are assigned to treatment and comparison conditions solely on the basis of a single cutoff score on a continuous assignment variable. The discontinuity in the functional form of the outcome at the cutoff represents the treatment effect, or the average treatment effect at the cutoff.…

  6. The design effects of voting advice applications: Comparing methods of calculating matches

    NARCIS (Netherlands)

    Louwerse, Tom; Rosema, Martin

    2014-01-01

    In election times more and more voters consult voting advice applications (VAAs), which show them what party or candidate provides the best match. The potential impact of these tools on election outcomes is substantial and hence it is important to study the effects of their design. This article focu

  7. Designing Chemistry Practice Exams for Enhanced Benefits: An Instrument for Comparing Performance and Mental Effort Measures

    Science.gov (United States)

    Knaus, Karen J.; Murphy, Kristen L.; Holme, Thomas A.

    2009-01-01

    The design and use of a chemistry practice exam instrument that includes a measure for student mental effort is described in this paper. Use of such an instrument can beneficial to chemistry students and chemistry educators as well as chemical education researchers from both a content and cognitive science perspective. The method for calculating…

  8. Bauhaus, Crown Hall, FAU: A Comparative Investigation of the Curriculum Design in Schools of Architecture

    Science.gov (United States)

    Mulrooney, Sarah

    2009-01-01

    One of the central themes addressed by this paper is the design of the curriculum for architectural education using three schools of architecture: the Bauhaus in Dessau, Crown Hall in Chicago and the Faculty of Architecture and Urbanism (FAU) in Sao Paulo. It also reflects on the practices in other schools such as Frank Lloyd Wright's Taliesin…

  9. Data-driven soft sensor design with multiple-rate sampled data: a comparative study

    DEFF Research Database (Denmark)

    Lin, Bao; Recke, Bodil; Schmidt, Torben M.

    2009-01-01

    to design quality soft sensors for cement kiln processes using data collected from a simulator and a plant log system. Preliminary results reveal that the WPLS approach is able to provide accurate one-step-ahead prediction. The regularized data lifting technique predicts the product quality of cement kiln...

  10. Preliminary Comparative Evaluation Study on Reference Design of GEN-IV SFR

    Energy Technology Data Exchange (ETDEWEB)

    Sim, Yoon Sub; Kim, Yeong Il; Hong, Ser Gi (and others)

    2005-11-15

    A fast reactor has a good transmutation capability and it enables breeding of fuel and use of a closed fuel cycle. By these characteristics of a fast reactor, the limited uranium resources of the world can be much more effectively utilized and the nuclear wastes of a high level of radioactivity and toxicity from the current nuclear power reactors of LWRs and HWRs can be drastically reduced in its volume and the management of the wastes can be easily treated. Also electricity can be generated more effectively since a fast reactor has the feature of high operation temperature. These features of a fast reactor makes it inevitable on a long term basis to construct fast reactors in Korea. The domestic fast reactor technology level, however, is at the level of coming out of a beginning stage and needs utilization of international expertise. Recently an international cooperation program called GIF has been formulated and our KALIMER was selected as one of the two reference designs for the international joint R and D works with JSFR of Japan. In the current frame of the GIF program, the two selected reference designs are supposed to be evaluated against each other in future and one design is to be finally selected. To make the international cooperation program directed more useful to our fast reactor technology development, it is required to strengthen the competitiveness of KALIMER so that it can be selected. To meet the necessity, a study was made in this research for pre-evaluation of the GIF reference designs and setting up plans for development of designs and technology that will enhance the competitiveness of KALIMER.

  11. A historical perspective of aircrew systems effects on aircraft design

    OpenAIRE

    Bauer, David O.

    1996-01-01

    Approved for public release; distribution in unlimited. The design of the aircrew workstation often has not been an orderly part of the overall aircraft design process but rather of much lower priority than the integration of the airframe and powerplant. However, the true test of the aircraft is how well the aircrew can use the aircraft for mission performance. NAVAIR has been seeking the establishment of an Aircrew Centered System Design discipline, to be addressed as an integral part of ...

  12. Comparing Two Types of Text-Tracking Design for Young Learners' E-Books

    Science.gov (United States)

    Wang, Pei-Yu

    2013-01-01

    This study examined the impact of e-book text-tracking design on 4th graders' (10-year-old children's) learning of Chinese characters. The e-books used in this study were created with Adobe Flash CS 5.5 and Action Script 3.0. This study was guided by two main questions: (1) Is there any difference in learning achievement (Chinese character…

  13. SURVEY DESIGN TO GRASP AND COMPARE USER'S ATTITUDES ON BUS RAPID TRANSIT (BRT IN DEVELOPING COUNTRIES

    Directory of Open Access Journals (Sweden)

    Thillaiampalam SIVAKUMAR

    2006-01-01

    Full Text Available In mitigating urban transportation problems and providing a sustainable transit system, rail-based systems have become popular. While rail-based systems are welcome in many developed countries, it is impractical for cities in developing countries due to the high cost of system building and operation. Thus, a staged or incremental adjustment towards fixed guide way transit implementation of greater interest to many agencies today, and these days it has started developing in terms of Bus Rapid Transit (BRT. As it is very new to developing cities, it is a challenge to get the users to understand the system and to grasp their attitude. Besides, there are many other general issues like literacy, lack of a sample frame etc. Survey design needs to be tuned carefully for these cities to obtain a resonant output. Concerning all these problems, a hypothetical questionnaire survey such as Stated Preference (SP has become popular. This study conducted a survey on BRT implementation with SP as a hypothetical tool at a selected corridor in Colombo, the capital of Sri Lanka. The main objectives were to identify questionnaire design(media effects, literacy of users, segmental variation, and the important variable(s. In this survey design, system explanation has been set in two slightly different ways (media: TEXT ∼ IMAGE for comparison and it was found that even a slight difference on design affected the users' response considerably. Income level could not be predicted directly, but car ownership was found to be a good predictor, it was found to be an important variable and it showed a correlation with literacy.

  14. Comparing the effect of low and high emittance on synchrotron radiation and beamline design

    Directory of Open Access Journals (Sweden)

    A Gholampour Azhir

    2017-08-01

    Full Text Available In this paper, we have discussed about the role of two emittance values suggested for Iranian Light Source Facility (ILSF (3.278 and 0.476 nm.rad on different radiation features of the synchrotron light sources (bending magnet, shaker and oscillator such as spot size, divergence of the beam on light spot, brilliance and important quantities in beamline design such as photon cross-section, optical element sizes and energy resolution  

  15. COMPARATIVE STUDY OF NONGSHIM INSTANT NOODLE PACKAGING DESIGN IN SOUTH KOREA AND IN INDONESIA

    Directory of Open Access Journals (Sweden)

    Listia Natadjaja

    2006-01-01

    Full Text Available These days due to the global market development, there are many products that are marketed outside the local area. I found that there are differences between local and export design in Nongshim instant noodle packaging, marketed in South Korea and in Indonesia. This study, discusses the differences between packaging design elements of the famous instant noodle brand in South Korea. Hopefully, through this study, we can have a description of what kind of design elements should be kept and what kind of information should be added or changed for the export product. Abstract in Bahasa Indonesia: Saat ini dikarenakan perkembangan pasar global, banyak produk yang dipasarkan di luar area lokal. Penulis menemukan perbedaan yang menarik anmtara desain lokal dan desain yang diperuntukan untuk eksport pada kemasan mie instant merek Nohngshim yang dipasarkan di Korea Selatan dan di Indonesia. Pada studi ini, penulis ingin membahas perbedaan apa sajakah yang terdapat pada elemen-elemen desain kemasan sebuah merek mie instant yang terkenal di Korea Selatan. Diharapkan melalui studi ini, kita bisa mendapatkan sebuah gambaran elemen-elemen desain apa saja yang harus dipertahankan dan informasi apa saja yang harus ditambahkan atau dirubah untuk produk ekspor. Kata kunci: mie instant Nongshim, Korea Selatan, Indonesia, desain kemasan.

  16. Matlab as a robust control design tool

    Science.gov (United States)

    Gregory, Irene M.

    1994-01-01

    This presentation introduces Matlab as a tool used in flight control research. The example used to illustrate some of the capabilities of this software is a robust controller designed for a single stage to orbit air breathing vehicles's ascent to orbit. The global requirements of the controller are to stabilize the vehicle and follow a trajectory in the presence of atmospheric disturbances and strong dynamic coupling between airframe and propulsion.

  17. A blended design in acute care training: similar learning results, less training costs compared with a traditional format.

    Science.gov (United States)

    Dankbaar, Mary E W; Storm, Diana J; Teeuwen, Irene C; Schuit, Stephanie C E

    2014-09-01

    Introduction There is a demand for more attractive and efficient training programmes in postgraduate health care training. This retrospective study aims to show the effectiveness of a blended versus traditional face-to-face training design. For nurses in postgraduate Acute and Intensive Care training, the effectiveness of a blended course design was compared with a traditional design. Methods In a first pilot study 57 students took a traditional course (2-h lecture and 2-h workshop) and 46 students took a blended course (2-h lecture and 2-h online self-study material). Test results were compared for both groups. After positive results in the pilot study, the design was replicated for the complete programme in Acute and Intensive Care. Now 16 students followed the traditional programme (11 days face-to-face education) and 31 students did the blended programme (7 days face-to-face and 40 h online self-study). An evaluation was done after the pilot and course costs were calculated. Results Results show that the traditional and blended groups were similar regarding the main characteristics and did not differ in learning results for both the pilot and the complete programme. Student evaluations of both designs were positive; however, the blended group were more confident that they had achieved the learning objectives. Training costs were reduced substantially. Conclusion The blended training design offers an effective and attractive training solution, leading to a significant reduction in costs.

  18. Implementation Fidelity of a Program Designed to Promote Personal and Social Responsibility through Physical Education: A Comparative Case Study

    Science.gov (United States)

    Pascual, Carmina; Escarti, Amparo; Llopis, Ramon; Gutierrez, Melchor; Marin, Diana; Wright, Paul M.

    2011-01-01

    The purpose of this qualitative comparative case study was to examine the implementation fidelity of a program designed to deliver the Teaching Personal and Social Responsibility (TPSR) model (Hellison, 2003) through physical education and its relationship with short-term outcomes for elementary school students. The research questions were: (a)…

  19. Comparing Single Case Design Overlap-Based Effect Size Metrics from Studies Examining Speech Generating Device Interventions

    Science.gov (United States)

    Chen, Mo; Hyppa-Martin, Jolene K.; Reichle, Joe E.; Symons, Frank J.

    2016-01-01

    Meaningfully synthesizing single case experimental data from intervention studies comprised of individuals with low incidence conditions and generating effect size estimates remains challenging. Seven effect size metrics were compared for single case design (SCD) data focused on teaching speech generating device use to individuals with…

  20. Incorporating Handling Qualities Analysis into Rotorcraft Conceptual Design

    Science.gov (United States)

    Lawrence, Ben

    2014-01-01

    This paper describes the initial development of a framework to incorporate handling qualities analyses into a rotorcraft conceptual design process. In particular, the paper describes how rotorcraft conceptual design level data can be used to generate flight dynamics models for handling qualities analyses. Also, methods are described that couple a basic stability augmentation system to the rotorcraft flight dynamics model to extend analysis to beyond that of the bare airframe. A methodology for calculating the handling qualities characteristics of the flight dynamics models and for comparing the results to ADS-33E criteria is described. Preliminary results from the application of the handling qualities analysis for variations in key rotorcraft design parameters of main rotor radius, blade chord, hub stiffness and flap moment of inertia are shown. Varying relationships, with counteracting trends for different handling qualities criteria and different flight speeds are exhibited, with the action of the control system playing a complex part in the outcomes. Overall, the paper demonstrates how a broad array of technical issues across flight dynamics stability and control, simulation and modeling, control law design and handling qualities testing and evaluation had to be confronted to implement even a moderately comprehensive handling qualities analysis of relatively low fidelity models. A key outstanding issue is to how to 'close the loop' with an overall design process, and options for the exploration of how to feedback handling qualities results to a conceptual design process are proposed for future work.

  1. A PTC Optimization and Control Surface Interference Study HSR Airframe Technical Review

    Science.gov (United States)

    Hicks, Raymond; Cliff, Susan; Rimlinger, Mark; Murman, Scott; Reuther, James

    1999-01-01

    This report considers the effect of canard and horizontal tail vertical position on the aerodynamic characteristics of the PTC configuration without nacelles and diverters. This analysis is followed by three optimization studies using canard and tail incidence as design variables in the first problem followed by an optimization run with canard and tail incidence and wing camber design variables and finally an optimization run with canard incidence and wing camber. The first problem was run at fixed lift while the other two problems were run at fixed angle of attack. The final investigation reported here will show data from a component buildup study using the PTC configuration. This final study will show the aerodynamic interference between the canard, wing and horizontal tail.

  2. Comparative Study of Website Page Size as Design Issue in Various Websites

    Directory of Open Access Journals (Sweden)

    Jatinder Manhas

    2014-12-01

    Full Text Available Websites are very important means of communication in this current era of information technology. Different institutions / organizations put lots of efforts to portray complete information on beautifully designed websites. Organizations these days concerned more in providing users with all facilities online through websites, which act as an interface through which a user can get his work done without physically visiting the organization. With this the responsibility of the designer and the concerned institutions / organizations increases manifold so that the websites behavior should remain interactive and quick enough for the user to avail all facilities through websites comfortably. Speed and size of a Website are directly related with each other. Size is very important when targeting users that don't have optimal Internet connections. Author in this paper developed an online tool using .NET Framework using C# to study webpage size as Design issue in various categories of the websites like Government, Commercial, Educational, Social networking and Job portals. The automated tool developed by author function on the basis of the different standards prescribed in W3C and prescribed in analysis performed in [2]. The tool act like a parser and renders the complete code of the website and then produces result by examining the memory requirements of the component files that contribute to the total size of the website. The results produced shows that out of the five different categories of websites, it can be concluded that none of the website categories undertaken follows the recommended standards of the World Wide Web consortium showing huge violation as far as recommended page size for different websites is concerned.

  3. A comparing design of satellite attitude control system based on reaction wheel

    Institute of Scientific and Technical Information of China (English)

    CHENG Hao; GE Sheng-min; SHEN Yi

    2008-01-01

    The disturbance caused by the reaction wheel with a current controller greatly influences the accuracy and stability of the satellite attitude control system.To solve this problem,the idea of speed feedback compensation control reaction wheel is put forward.This paper introduces the comparison on design and performance of two satellite attitude control systems,which are separately based on the current control reaction wheel and the speed feedback compensation control reaction wheel.Analysis shows that the speed feedback compensation control flywheel system may effectively suppress the torque fluctuation.Simulation results indicate that the satellite attitude control system with the speed feedback compensation control flywheel has improved performance.

  4. Application of comparative modelling to the design and discovery of novel GPCR ligands

    OpenAIRE

    Pala, Daniele

    2012-01-01

    This Ph.D. project was mainly focused on the building and validation of the three-dimensional structures of G protein-coupled receptors and on the assessment of their reliability and usefulness in the drug design process. Different GPCRs have been extensively investigated, for which X-ray crystal structures were either available or not: the MT1 and MT2 melatonin receptors, the 5-HT2C serotonin receptor, the H3 histamine receptor, the beta2 adrenergic receptor and the A2A adenosine receptor. A...

  5. Designing online audiovisual heritage services: an empirical study of two comparable online video services

    NARCIS (Netherlands)

    Ongena, G.; van de Wijngaert, Lidwien; Huizer, E.

    2013-01-01

    The purpose of this study is to seek input for a new online audiovisual heritage service. In doing so, we assess comparable online video services to gain insights into the motivations and perceptual innovation characteristics of the video services. The research is based on data from a Dutch survey

  6. Real-time 2D spatially selective MRI experiments: Comparative analysis of optimal control design methods.

    Science.gov (United States)

    Maximov, Ivan I; Vinding, Mads S; Tse, Desmond H Y; Nielsen, Niels Chr; Shah, N Jon

    2015-05-01

    There is an increasing need for development of advanced radio-frequency (RF) pulse techniques in modern magnetic resonance imaging (MRI) systems driven by recent advancements in ultra-high magnetic field systems, new parallel transmit/receive coil designs, and accessible powerful computational facilities. 2D spatially selective RF pulses are an example of advanced pulses that have many applications of clinical relevance, e.g., reduced field of view imaging, and MR spectroscopy. The 2D spatially selective RF pulses are mostly generated and optimised with numerical methods that can handle vast controls and multiple constraints. With this study we aim at demonstrating that numerical, optimal control (OC) algorithms are efficient for the design of 2D spatially selective MRI experiments, when robustness towards e.g. field inhomogeneity is in focus. We have chosen three popular OC algorithms; two which are gradient-based, concurrent methods using first- and second-order derivatives, respectively; and a third that belongs to the sequential, monotonically convergent family. We used two experimental models: a water phantom, and an in vivo human head. Taking into consideration the challenging experimental setup, our analysis suggests the use of the sequential, monotonic approach and the second-order gradient-based approach as computational speed, experimental robustness, and image quality is key. All algorithms used in this work were implemented in the MATLAB environment and are freely available to the MRI community.

  7. AN EXPANSIVE AND COMPARABLE STUDY OF EFFECTUAL ALGORITHMS FOR PLACEMENT IN PHYSICAL DESIGN

    Directory of Open Access Journals (Sweden)

    PRAGYA SHARMA

    2014-11-01

    Full Text Available This review paper consists of comprehensive study of VLSI algorithms for placement in physical design. The work has been classified under different perspectives like performance,area,wirelength,cost and power and the algorithms address the coverage and optimization of these factors. Placement is a major step for VLSI physical design as it involves placing the blocks on the chip with minimum possible area consumption however the initial placement is done by constructive placement algorithms such as constructive and iterative placement. Under the survey work which is done, the knowledge of placement algorithms with their merits and limitations has been provided so that according to the requirement one can choose the best algorithm. The survey involves simulation of different algorithms implemented in C and C++ programming languages. Tools from the EDA vendors have been provided for the simulation work so as to achieve the results and to have best possible outcomes. We survey the history of placement research, the progress achieved up to now, and outstanding challenges. Some future work has also been mentioned in which the research work can be carried upon.

  8. 14 CFR 21.93 - Classification of changes in type design.

    Science.gov (United States)

    2010-01-01

    ... engine and nacelle carriage external to the skin of the airplane (and return of the pylon or other external mount), or (iii) Time-limited engine and/or nacelle changes, where the change in type design... flight and is not part of an airframe or engine. An “acoustical change” does not include: (A) Addition...

  9. Designing for the home: a comparative study of support aids for central heating systems.

    Science.gov (United States)

    Sauer, J; Wastell, D G; Schmeink, C

    2009-03-01

    The study examined the influence of different types of enhanced system support on user performance during the management of a central heating system. A computer-based simulation of a central heating system, called CHESS V2.0, was used to model different interface options, providing different support facilities to the user (e.g., historical, predictive, and instructional displays). Seventy-five participants took part in the study and completed a series of operational scenarios under different support conditions. The simulation environment allowed the collection of performance measures (e.g., energy consumption), information sampling, and system control behaviour. Subjective user evaluations of various aspects of the system were also measured. The results showed performance gains for predictive displays whereas no such benefits were observed for the other display types. The data also revealed that status and predictive displays were valued most highly by users. The implications of the findings for designers of central heating systems are discussed.

  10. Design, comparative study and analysis of CDMA for different modulation techni

    Directory of Open Access Journals (Sweden)

    Arun Kumar

    2015-11-01

    Full Text Available In this work, we have design a MIMO–CDMA using 4 ∗ 8 antennas with the combination of MMSE (Minimum Mean square Error Equalizer for BPSK (Binary Phase shift Keying, QPSK (Quadrature Phase Shift Keying, 16-QAM, 64-QAM and 256-QAM (Quadrature Amplitude Modulation modulation schemes. The analysis is built on the basis of transmit–received signal, constellation and MMSE plot simulated on a MatLab/Simulink. On the basis of BER (Bit-Error-Rate, it is also concluded that this work is mostly suitable for high order modulation schemes as the BER of 16-qam, 64-QAM and 256-QAM is zero. The proposed study has increased the quality of the wireless link and Inter-Symbol-Interference (ISI is likewise cut by applying a combination of MMSE and MIMO (Multiple In and Multiple Out with OSTBC (Orthogonal space Time Block Code encoder and combiner.

  11. Building efficient comparative effectiveness trials through adaptive designs, utility functions, and accrual rate optimization: finding the sweet spot.

    Science.gov (United States)

    Gajewski, Byron J; Berry, Scott M; Quintana, Melanie; Pasnoor, Mamatha; Dimachkie, Mazen; Herbelin, Laura; Barohn, Richard

    2015-03-30

    The time is right for the use of Bayesian Adaptive Designs (BAD) in comparative effectiveness trials. For example, Patient Centered Outcomes Research Institute has joined the Food and Drug Administration and National Intitutes of Health in adopting policies/guidelines encouraging their use. There are multiple aspects to BAD that need to be considered when designing a comparative effectiveness design. First, the adaptation rules can determine the expected size of the trial. Second, a utility function can be used to combine extremely important co-endpoints (e.g., efficacy and tolerability) and is a valuable tool for incorporating clinical expertise and potentially patient preference. Third, accrual rate is also very, very important. Specifically, there is a juxtaposition related to accrual and BAD. If accrual rate is too fast we never gain efficient information for adapting. If accrual rate is too slow we never finish the clinical trial. We propose methodology for finding the 'sweet spot' for BAD that addresses these as design parameters. We demonstrate the methodology on a comparative effectiveness BAD of pharmaceutical agents in cryptogenic sensory polyneuropathy. The study has five arms with two endpoints that are combined with a utility function. The accrual rate is assumed to stem from multiple sites. We perform simulations from which the composite accrual rates across sites result in various piecewise Poisson distributions as parameter inputs. We balance both average number of patients needed and average length of time to finish the study.

  12. In vitro evaluation of force-expansion characteristics in a newly designed orthodontic expansion screw compared to conventional screws

    Directory of Open Access Journals (Sweden)

    Oshagh Morteza

    2009-01-01

    Full Text Available Objective : Expansion screws like Hyrax, Haas and other types, produce heavy interrupted forces which are unfavorable for dental movement and could be harmful to the tooth and periodontium. The other disadvantage of these screws is the need for patient cooperation for their regular activation. The purpose of this study was to design a screw and compare its force- expansion curve with other types. Materials and Methods : A new screw was designed and fabricated in the same dimension, with conventional types, with the ability of 8 mm expansion (Free wire length: 12 mm, initial compression: 4.5 mm, spring wire diameter: 0.4 mm, spring diameter: 3 mm, number of the coils: n0 ine, material: s0 tainless steel. In this in vitro study, the new screw was placed in an acrylic orthodontic appliance, and after mounting on a stone cast, the force-expansion curve was evaluated by a compression test machine and compared to other screws. Results : Force-expansion curve of designed screw had a flatter inclination compared to other screws. Generally it produced a light continuous force (two to 3.5 pounds for every 4 mm of expansion. Conclusion : In comparison with heavy and interrupted forces of other screws, the newly designed screw created light and continuous forces.

  13. The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) program: McDonnell-Douglas Helicopter Company achievements

    Science.gov (United States)

    Toossi, Mostafa; Weisenburger, Richard; Hashemi-Kia, Mostafa

    1993-01-01

    This paper presents a summary of some of the work performed by McDonnell Douglas Helicopter Company under NASA Langley-sponsored rotorcraft structural dynamics program known as DAMVIBS (Design Analysis Methods for VIBrationS). A set of guidelines which is applicable to dynamic modeling, analysis, testing, and correlation of both helicopter airframes and a large variety of structural finite element models is presented. Utilization of these guidelines and the key features of their applications to vibration modeling of helicopter airframes are discussed. Correlation studies with the test data, together with the development and applications of a set of efficient finite element model checkout procedures, are demonstrated on a large helicopter airframe finite element model. Finally, the lessons learned and the benefits resulting from this program are summarized.

  14. Comparative Analysis of the Wing Geometry Design for an Aerodynamic Gondola of a Recoverable and Reusable Probe Balloon

    Directory of Open Access Journals (Sweden)

    David Rubio Forero

    2015-10-01

    Full Text Available The present paper describes two conceptual wing designs that maintain equals the wing area, the aspect ratio, the wing span and the aerodynamic profiles, varying wing shape by changing the length of the root and tip chord of each model, in order to determinate the most efficient wing geometry design of an aerodynamic nacelle than could be implemented in a recoverable and reusable radio probe. The lift and drag coefficients are analyzed in function of the angle of attack, as a comparative parameter, finding an improvement on the lift when the tip chord has more length.

  15. Comparing unilateral and bilateral upper limb training: The ULTRA-stroke program design

    Directory of Open Access Journals (Sweden)

    Koppe Peter

    2009-11-01

    Full Text Available Abstract Background About 80% of all stroke survivors have an upper limb paresis immediately after stroke, only about a third of whom (30 to 40% regain some dexterity within six months following conventional treatment programs. Of late, however, two recently developed interventions - constraint-induced movement therapy (CIMT and bilateral arm training with rhythmic auditory cueing (BATRAC - have shown promising results in the treatment of upper limb paresis in chronic stroke patients. The ULTRA-stroke (acronym for Upper Limb TRaining After stroke program was conceived to assess the effectiveness of these interventions in subacute stroke patients and to examine how the observed changes in sensori-motor functioning relate to changes in stroke recovery mechanisms associated with peripheral stiffness, interlimb interactions, and cortical inter- and intrahemispheric networks. The present paper describes the design of this single-blinded randomized clinical trial (RCT, which has recently started and will take several years to complete. Methods/Design Sixty patients with a first ever stroke will be recruited. Patients will be stratified in terms of their remaining motor ability at the distal part of the arm (i.e., wrist and finger movements and randomized over three intervention groups receiving modified CIMT, modified BATRAC, or an equally intensive (i.e., dose-matched conventional treatment program for 6 weeks. Primary outcome variable is the score on the Action Research Arm test (ARAT, which will be assessed before, directly after, and 6 weeks after the intervention. During those test sessions all patients will also undergo measurements aimed at investigating the associated recovery mechanisms using haptic robots and magneto-encephalography (MEG. Discussion ULTRA-stroke is a 3-year translational research program which aims (1 to assess the relative effectiveness of the three interventions, on a group level but also as a function of patient

  16. Design and diversity in bacterial chemotaxis: a comparative study in Escherichia coli and Bacillus subtilis.

    Directory of Open Access Journals (Sweden)

    Christopher V Rao

    2004-02-01

    Full Text Available Comparable processes in different species often involve homologous genes. One question is whether the network structure, in particular the feedback control structure, is also conserved. The bacterial chemotaxis pathways in E. coli and B. subtilis both regulate the same task, namely, excitation and adaptation to environmental signals. Both pathways employ many orthologous genes. Yet how these orthologs contribute to network function in each organism is different. To investigate this problem, we propose what is to our knowledge the first computational model for B. subtilis chemotaxis and compare it to previously published models for chemotaxis in E. coli. The models reveal that the core control strategy for signal processing is the same in both organisms, though in B. subtilis there are two additional feedback loops that provide an additional layer of regulation and robustness. Furthermore, the network structures are different despite the similarity of the proteins in each organism. These results demonstrate the limitations of pathway inferences based solely on homology and suggest that the control strategy is an evolutionarily conserved property.

  17. Evaluation of Airframe Noise Reduction Concepts via Simulations Using a Lattice Boltzmann Approach

    Science.gov (United States)

    Fares, Ehab; Casalino, Damiano; Khorrami, Mehdi R.

    2015-01-01

    Unsteady computations are presented for a high-fidelity, 18% scale, semi-span Gulfstream aircraft model in landing configuration, i.e. flap deflected at 39 degree and main landing gear deployed. The simulations employ the lattice Boltzmann solver PowerFLOW® to simultaneously capture the flow physics and acoustics in the near field. Sound propagation to the far field is obtained using a Ffowcs Williams and Hawkings acoustic analogy approach. In addition to the baseline geometry, which was presented previously, various noise reduction concepts for the flap and main landing gear are simulated. In particular, care is taken to fully resolve the complex geometrical details associated with these concepts in order to capture the resulting intricate local flow field thus enabling accurate prediction of their acoustic behavior. To determine aeroacoustic performance, the farfield noise predicted with the concepts applied is compared to high-fidelity simulations of the untreated baseline configurations. To assess the accuracy of the computed results, the aerodynamic and aeroacoustic impact of the noise reduction concepts is evaluated numerically and compared to experimental results for the same model. The trends and effectiveness of the simulated noise reduction concepts compare well with measured values and demonstrate that the computational approach is capable of capturing the primary effects of the acoustic treatment on a full aircraft model.

  18. A comparative study of climatically responsive house design at various periods of Northern Cyprus architecture

    Energy Technology Data Exchange (ETDEWEB)

    Ozay, N. [Eastern Mediterranean University, Magusa (Turkey). Department of Architecture

    2005-06-15

    Architecture is considered as a mirror of a civilization that is shaped up by needs, society, technology, culture and climate. Except climate these factors are modifiable and changeable with respect to time. Climate is a fixed environmental factor affecting architecture and its built environment. Thus, different climatic conditions pertaining to the countries force them to take special architectural precautions to create more comfortable living spaces. Furthermore, these can define the architectural characteristics of various countries at different time spans. On the basis of this argument, with this paper it is intended to reveal the main approaches and criteria for climatically responsive houses and settlements in Northern Cyprus. Contribution of the article to this field is the discussion of the climatic considerations of different architectural periods in urban and rural areas. The periods such as Ottoman (1571-1878), British (1878-1960) and Modern (1960-present) are the most significant ones discussed together with the Cypriot vernacular architecture. Site planning, building design and specific building elements are the main parameters handled to analyse the climatic considerations. In addition, the impact of socio-economy, technology, culture, politics and building management strategies have also been discussed during the process of evaluation of each period and vernacular architecture. (author)

  19. Compare the difference of architecture design in Hong Kong and Penang – Exterior wall

    Directory of Open Access Journals (Sweden)

    Liu Wen Tao

    2015-12-01

    Full Text Available This research focuses on the exterior wall of architecture design of Hong Kong and Penang, it also analyzes how light pollution affects human life. As we know, Hong Kong prefers to use steel to build skyscrapers and middle or high rise buildings. However, Penang prefers to use concrete to do the construction. So, there are some advantages and disadvantages between the glass curtain wall and concrete wall in Hong Kong and Penang. The researcher used 400 samples to determine effect of the glass curtain wall and concrete wall on human life in Hong Kong and Penang separately. The result is light pollution created by glass curtain wall in Hong Kong is a serious problem to residents’ life. The glass curtain wall seriously glaze people’s eyes who drive or walk on the street. Thus, many car accidents were caused by this problem. The concrete wall is more often contaminated by fungus and difficult to clean. But, concrete wall is more natural and green for humans. Therefore, from the sustainable aspect that concrete is more healthy for humans, the previous researchers suggest that if the exterior wall is a mixture of both glass curtain and concrete it will not cause light pollution and will be easily involved in the natural environment.

  20. A Comparative Study Of Wireless Technologies Used For Designing Home Automations System

    Directory of Open Access Journals (Sweden)

    Ashish J. Ingle

    2011-08-01

    Full Text Available Bluetooth (over IEEE 802.15.1, ultra-wideband (UWB, over IEEE 802.15.3, ZigBee (over IEEE 802.15.4, and Wi-Fi (over IEEE 802.11 are four protocol standards for short- range wireless communications with low power consumption. From an application point of view, Bluetooth is intended for a cordless mouse, keyboard, and hands-free headset, UWB is oriented to high-bandwidth multimedia links. ZigBee is designed for reliable wirelessly networked monitoring and control networks, while Wi-Fi is directed at computer-to-computer connections as an extension or substitution of cabled networks. In this paper, we provide a study of these popular wireless communication standards, evaluating their main features and behaviors in terms of various metrics, including the transmission time, data coding efficiency, complexity, and power consumption. It is believed that the comparison presented in this paper would benefit application engineers in selecting an appropriate protocol.

  1. NDARC - NASA Design and Analysis of Rotorcraft Validation and Demonstration

    Science.gov (United States)

    Johnson, Wayne

    2010-01-01

    Validation and demonstration results from the development of the conceptual design tool NDARC (NASA Design and Analysis of Rotorcraft) are presented. The principal tasks of NDARC are to design a rotorcraft to satisfy specified design conditions and missions, and then analyze the performance of the aircraft for a set of off-design missions and point operating conditions. The aircraft chosen as NDARC development test cases are the UH-60A single main-rotor and tail-rotor helicopter, the CH-47D tandem helicopter, the XH-59A coaxial lift-offset helicopter, and the XV-15 tiltrotor. These aircraft were selected because flight performance data, a weight statement, detailed geometry information, and a correlated comprehensive analysis model are available for each. Validation consists of developing the NDARC models for these aircraft by using geometry and weight information, airframe wind tunnel test data, engine decks, rotor performance tests, and comprehensive analysis results; and then comparing the NDARC results for aircraft and component performance with flight test data. Based on the calibrated models, the capability of the code to size rotorcraft is explored.

  2. Design of A 5-Bit Fully Parallel Analog to Digital Converter Using Common Gate Differrential Mos Pair-Based Comparator

    Science.gov (United States)

    Aytar, Oktay

    2015-09-01

    This paper presents a novel comparator structure based on the common gate differential MOS pair. The proposed comparator has been applied to fully parallel analog to digital converter (A/D converter). Furthermore, this article presents 5 bit fully parallel A/D Converter design using the cadence IC5141 design platform and NCSU(North Carolina State University) design kit with 0.18 μm CMOS technology library. The proposed fully parallel A/D converter consist of resistor array block, comparator block, 1-n decoder block and programmable logic array. The 1-n decoder block includes latch block and thermometer code circuit that is implemented using transmission gate based multiplexer circuit. Thus, sampling frequency and analog bandwidth are increased. The INL and DNL of the proposed fully parallel A/D converter are (0/ + 0.63) LSB and (-0.26/ + 0.31) LSB at a sampling frequency of 5 GS/s with an input signal of 50 MHz, respectively. The proposed fully parallel A/D Converter consumes 340 mW from 1.8 V supply.

  3. An evaluation of two conducted electrical weapons and two probe designs using a swine comparative cardiac safety model.

    Science.gov (United States)

    Dawes, Donald Murray; Ho, Jeffrey D; Moore, Johanna C; Miner, James R

    2013-09-01

    Despite human laboratory and field studies that have demonstrated a reasonable safety profile for TASER brand conducted electrical weapons (CEW), the results of some swine studies and arrest related deaths temporal to the use of the CEWs continue to raise questions regarding cardiac safety. TASER International, Inc., has released a new CEW, the TASER X2, touted to have a better safety profile than its long-standing predecessor, the TASER X26. We have developed a model to assess the relative cardiac safety of CEWs and used it to compare the TASER X2 and the TASER X26. This safety model was also used to assess the relative safety of an experimental probe design as compared to the standard steel probe. Our results suggest that the TASER X2 has an improved safety margin over the TASER X26. The new probe design also has promise for enhanced cardiac safety, although may have some disadvantages when compared to the existing design which would make field use impractical.

  4. Comparative study of gas-analyzing systems designed for continuous monitoring of TPP emissions

    Science.gov (United States)

    Kondrat'eva, O. E.; Roslyakov, P. V.

    2017-06-01

    Determining the composition of combustion products is important in terms of both control of emissions into the atmosphere from thermal power plants and optimization of fuel combustion processes in electric power plants. For this purpose, the concentration of oxygen, carbon monoxide, nitrogen, and sulfur oxides in flue gases is monitored; in case of solid fuel combustion, fly ash concentration is monitored as well. According to the new nature conservation law in Russia, all large TPPs shall be equipped with continuous emission monitoring and measurement systems (CEMMS) into the atmosphere. In order to ensure the continuous monitoring of pollutant emissions, direct round-the-clock measurements are conducted with the use of either domestically produced or imported gas analyzers and analysis systems, the operation of which is based on various physicochemical methods and which can be generally used when introducing CEMMS. Depending on the type and purposes of measurement, various kinds of instruments having different features may be used. This article represents a comparative study of gas-analysis systems for measuring the content of polluting substances in exhaust gases based on various physical and physicochemical analysis methods. It lists basic characteristics of the methods commonly applied in the area of gas analysis. It is proven that, considering the necessity of the long-term, continuous operation of gas analyzers for monitoring and measurement of pollutant emissions into the atmosphere, as well as the requirements for reliability and independence from aggressive components and temperature of the gas flow, it is preferable to use optical gas analyzers for the aforementioned purposes. In order to reduce the costs of equipment comprising a CEMMS at a TPP and optimize the combustion processes, electrochemical and thermomagnetic gas analyzers may also be used.

  5. Comparison of two incision designs for surgical removal of impacted mandibular third molar: A randomized comparative clinical study

    Directory of Open Access Journals (Sweden)

    Adarsh Desai

    2014-01-01

    Full Text Available Objective: The objective of this study is to investigate the influence of flap design on visibility and accessibility during removal of impacted third molar and hematoma formation, wound gaping and healing of flap post-operatively. Study Design: The randomized prospective comparative study included 30 patients with impacted mandibular third molars. Two flap designs namely "envelope flap" (Koener′s incision and ′triangular flap′ (Ward′s incision were used. After 7 days, sutures were removed and status of wound, periodontal health, and progress of healing was assessed. Patients were followed through 15 days to judge the incidence of post-operative complications in both groups. Results: No statistical differences were noted between the groups in terms of visibility, accessibility, excessive bleeding during surgery, healing of flap, sensitivity of adjacent teeth, and dry socket. A statistically significant difference was observed in post-operative hematoma, wound gaping, and distal pocket in adjacent tooth, which was significant in Ward′s triangular incision group in comparison to Koeiner′s envelope incision group. Conclusion: The selection of the flap design is dependent on needs of the case and preference of the operating surgeon and does not seem to have a significant influence on the health of tissues. In order to avoid wide area of exposure of bone, the operating surgeon should clinically and radiographically assess the designing of incision and mucoperiosteal flap, the clinical relevance is still debatable.

  6. Micro-mechanical damage accumulation in airframe materials and structural components

    Science.gov (United States)

    Tiku, Sanjay

    A simple and flexible ACPD probe design methodology incorporating current focusing technique was developed for on-line as well as off-line measurements in laboratory and industrial scale test environments. The effectiveness of the current focusing technique and the resulting three-dimensional control of the current density distribution was demonstrated. The ACPD technique was successfully used to obtain strain calibration and crack calibration curves in 7075 Al alloys. This also included quantifying the effect of residual stresses on ACPD signal. The smallest crack depth detected was 140 mum at 120 kHz, 5 amp. and 3000 gain. A quadratic relation was found to correlate crack depth with potential change. The ACPD sensors were installed on a F-18 aircraft undergoing full scale test at Canadair. The sensors were able to measure the response of the structure to spectrum loading. A crack was detected by the ACPD sensors only after 3400 SFH and it was established that ACPD probes were able to detect the crack long before (˜2500 SFH) any other established techniques utilized by DND/Canadair was able to detect the crack. The technique was successfully used to characterize short crack growth behaviour of naturally initiated fatigue cracks in Al alloys from 40 mum crack depth onwards. The cracks were semi-elliptical in shape and crack growth along the notch root was faster than crack growth into the specimen. The effect of various grain orientations on short crack growth behaviour was studied. The crack tip interactions with grain boundaries were shown to control the SCG behaviour of Al alloys even at notch root peak stresses close to yield stress of the material. This effect was less prominent at notch root peak stresses considerably higher than yield stresses. The fatigue crack growth rates were correlated with the SIF (K) calculated using Newman's model for thumb nail cracks. This correlation resulted in a very large scatter in the data. The fatigue crack growth rate data

  7. Characterization of Unsteady Flow Structures Around Tandem Cylinders for Component Interaction Studies in Airframe Noise

    Science.gov (United States)

    Jenkins, Luther N.; Khorrami, Mehdi R.; Choudhari, Meelan M.; McGinley, Catherine B.

    2005-01-01

    A joint computational and experimental study has been performed at NASA Langley Research Center to investigate the unsteady flow generated by the components of an aircraft landing gear system. Because the flow field surrounding a full landing gear is so complex, the study was conducted on a simplified geometry consisting of two cylinders in tandem arrangement to isolate and characterize the pertinent flow phenomena. This paper focuses on the experimental effort where surface pressures, 2-D Particle Image Velocimetry, and hot-wire anemometry were used to document the flow interaction around the two cylinders at a Reynolds Number of 1.66 x 10(exp 5), based on cylinder diameter, and cylinder spacing-todiameter ratios, L/D, of 1.435 and 3.70. Transition strips were applied to the forward cylinder to produce a turbulent boundary layer upstream of the flow separation. For these flow conditions and L/D ratios, surface pressures on both the forward and rear cylinders show the effects of L/D on flow symmetry, base pressure, and the location of flow separation and attachment. Mean velocities and instantaneous vorticity obtained from the PIV data are used to examine the flow structure between and aft of the cylinders. Shedding frequencies and spectra obtained using hot-wire anemometry are presented. These results are compared with unsteady, Reynolds-Averaged Navier-Stokes (URANS) computations for the same configuration in a companion paper by Khorrami, Choudhari, Jenkins, and McGinley (2005). The experimental dataset produced in this study provides information to better understand the mechanisms associated with component interaction noise, develop and validate time-accurate computer methods used to calculate the unsteady flow field, and assist in modeling of the radiated noise from landing gears.

  8. Sliding Mode Control Applied to Reconfigurable Flight Control Design

    Science.gov (United States)

    Hess, R. A.; Wells, S. R.; Bacon, Barton (Technical Monitor)

    2002-01-01

    Sliding mode control is applied to the design of a flight control system capable of operating with limited bandwidth actuators and in the presence of significant damage to the airframe and/or control effector actuators. Although inherently robust, sliding mode control algorithms have been hampered by their sensitivity to the effects of parasitic unmodeled dynamics, such as those associated with actuators and structural modes. It is known that asymptotic observers can alleviate this sensitivity while still allowing the system to exhibit significant robustness. This approach is demonstrated. The selection of the sliding manifold as well as the interpretation of the linear design that results after introduction of a boundary layer is accomplished in the frequency domain. The design technique is exercised on a pitch-axis controller for a simple short-period model of the High Angle of Attack F-18 vehicle via computer simulation. Stability and performance is compared to that of a system incorporating a controller designed by classical loop-shaping techniques.

  9. Mechanistic insights from comparing intrinsic clearance values between human liver microsomes and hepatocytes to guide drug design.

    Science.gov (United States)

    Di, Li; Keefer, Christopher; Scott, Dennis O; Strelevitz, Timothy J; Chang, George; Bi, Yi-An; Lai, Yurong; Duckworth, Jonathon; Fenner, Katherine; Troutman, Matthew D; Obach, R Scott

    2012-11-01

    Metabolic stability of drug candidates are often determined in both liver microsome and hepatocyte assays. Comparison of intrinsic clearance values between the two assays provides additional information to guide drug design. Intrinsic clearance values from human liver microsomes and hepatocytes were compared for a set of commercial drugs with known metabolic pathways and transporter characteristics. The results showed that for compounds that were predominately metabolized by CYP mediated mechanisms, the intrinsic clearance values from the two assays were comparable. For compounds with non-CYP pathways, such as UGT and AO, intrinsic clearance was faster in hepatocytes than in microsomes. Substrates of uptake or efflux transporters in this study did not have significant differences of intrinsic clearance between microsomes and hepatocytes, when uptake into the hepatocytes was not the rate-limiting step. When hepatic uptake was rate limiting, intrinsic clearance in microsomes was faster than that in hepatocytes, which was more prevalent for compounds with rapid metabolism. Low passive permeability can limit the exposure to drug molecules to the metabolizing enzymes in the hepatocytes in relationship to the rate of metabolism. The faster the rate of metabolism, the higher permeability is needed for molecule to enter the cells and not becoming rate-limiting. The findings are very useful for drug discovery programs to gain additional insights on mechanistic information to help drug design without added experiments. Follow-up studies can then be designed to address specific questions.

  10. Corrosion in airframes

    OpenAIRE

    PETROVIC ZORAN C.

    2016-01-01

    The introductory chapter provides a brief reference to the issue of corrosion and corrosion damage to aircraft structures. Depending on the nature and dimensions of this non uniformity, three different categories of corrosion are defined: uniform, selective and localized corrosion. The following chapters present the forms of corrosion that can occur in three defined categories of corrosion. Conditions that cause certain types of corrosion in various corrosive environments are discussed. Examp...

  11. Airframe/Propulsion Interference

    Science.gov (United States)

    1975-03-01

    Ij % R 5 T Tc V Ifevre de sortie de la tuyfere secondaire, coefficient de frottement parietal. " d1 injection g&ieralis^. " de poussee...dufrottement sur la tuyere seocndaire est base sur la relation de Ludwieg et Tlllman aui donne le coefficient de frottement incompressible T/i en...fuseau d’une soufflante miniaturiste entrafnee par une turbine k air comprimt ; dans ce cas l’ecart des coefficients de dibit captes entre la maquette

  12. CORROSION IN AIRFRAMES

    OpenAIRE

    PETROVIC ZORAN C.

    2016-01-01

    The introductory chapter provides a brief reference to the issue of corrosion and corrosion damage to aircraft structures. Depending on the nature and dimensions of this non uniformity, three different categories of corrosion are defined: uniform, selective and localized corrosion. The following chapters present the forms of corrosion that can occur in three defined categories of corrosion. Conditions that cause certain types of corrosion in various corrosive environments are discussed. Examp...

  13. Ramjets: Airframe integration

    NARCIS (Netherlands)

    Moerel, J.L.; Halswijk, W.

    2010-01-01

    These notes deal with the integration of a (sc)ramjet engine in either an axisymmetric or a waverider type of cruise missile configuration. The integration aspects relate to the integration of the external and internal flow paths in geometrical configurations that are being considered worldwide. Int

  14. Does Feedback Design Matter? A Neurofeedback Study Comparing Immersive Virtual Reality and Traditional Training Screens in Elderly

    Directory of Open Access Journals (Sweden)

    Silvia Erika Kober

    2017-09-01

    Full Text Available Neurofeedback (NF is a Brain-Computer Interface (BCI application, in which the brain activity is fed back to the user in real-time enabling voluntary brain control. In this context, the significance of the feedback design is mainly unexplored. Highly immersive feedback scenarios using virtual reality (VR technique are available. However, their effects on subjective user experience as well as on objective outcome measures remain open. In the present article, we discuss the general pros and cons of using VR as feedback modality in BCI applications. Furthermore, we report on the results of an empirical study, in which the effects of traditional two-dimensional and three-dimensional VR based feedback scenarios on NF training performance and user experience in healthy older individuals and neurologic patients were compared. In conclusion, we suggest indications and contraindications of immersive VR feedback designs in BCI applications. Our results show that findings in healthy individuals are not always transferable to patient populations having an impact on serious game and feedback design.

  15. Design and comparative analysis of 10 MW class superconducting wind power generators according to different types of superconducting wires

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Hae-Jin, E-mail: haejin90@changwon.ac.kr [Changwon National University, 55306 Sarim-dong, Changwon 641-773 (Korea, Republic of); Kim, Gyeong-Hun; Kim, Kwangmin; Park, Minwon [Changwon National University, 55306 Sarim-dong, Changwon 641-773 (Korea, Republic of); Yu, In-Keun, E-mail: yuik@changwon.ac.kr [Changwon National University, 55306 Sarim-dong, Changwon 641-773 (Korea, Republic of); Kim, Jong-Yul [Korea Electrotechnology Research Institute, Changwon 641-120 (Korea, Republic of)

    2013-11-15

    Highlights: •10 MW SC wind power generators are designed using different types of SC wires. •SCSGs using YBCO and Bi-2223 wires are optimized by the modified Taguchi method. •The results demonstrate a proper type of SC wire for the optimal design of SCSG. -- Abstract: Wind turbine concepts can be classified into the geared type and the gearless type. The gearless type wind turbine is more attractive due to advantages of simplified drive train and increased energy yield, and higher reliability because the gearbox is omitted. In addition, this type resolves the weight issue of the wind turbine with the light weight of gearbox. However, because of the low speed operation, this type has disadvantage such as the large diameter and heavy weight of generator. Super-Conducting (SC) wind power generator can reduce the weight and volume of a wind power system. Properties of superconducting wire are very different from each company. This paper considers the design and comparative analysis of 10 MW class SC wind power generators according to different types of SC wires. Super-Conducting Synchronous Generators (SCSGs) using YBCO and Bi-2223 wires are optimized by an optimal method. The magnetic characteristics of the SCSGs are investigated using the finite elements method program. The optimized specifications of the SCSGs are discussed in detail, and the optimization processes can be used effectively to develop large scale wind power generation systems.

  16. A comparative study of differential evolution and genetic algorithms for optimizing the design of water distribution systems

    Institute of Scientific and Technical Information of China (English)

    Xiao-lei DONG; Sui-qing LIU; Tao TAO; Shu-ping LI; Kun-lun XIN

    2012-01-01

    The differential evolution (DE) algorithm has been received increasing attention in terms of optimizing the design for the water distribution systems (WDSs).This paper aims to carry out a comprehensive performance comparison between the new emerged DE algorithm and the most popular algorithm-the genetic algorithm (GA).A total of six benchmark WDS case studies were used with the number of decision variables ranging from 8 to 454.A preliminary sensitivity analysis was performed to select the most effective parameter values for both algorithms to enable the fair comparison.It is observed from the results that the DE algorithm consistently outperforms the GA in terms of both efficiency and the solution quality for each case study.Additionally,the DE algorithm was also compared with the previously published optimization algorithms based on the results for those six case studies,indicating that the DE exhibits comparable performance with other algorithms.It can be concluded that the DE is a newly promising optimization algorithm in the design of WDSs.

  17. Multiplex PCR for detection of the Vibrio genus and five pathogenic Vibrio species with primer sets designed using comparative genomics.

    Science.gov (United States)

    Kim, Hyun-Joong; Ryu, Ji-Oh; Lee, Shin-Young; Kim, Ei-Seul; Kim, Hae-Yeong

    2015-10-26

    The genus Vibrio is clinically significant and major pathogenic Vibrio species causing human Vibrio infections are V. cholerae, V. parahaemolyticus, V. vulnificus, V. alginolyticus and V. mimicus. In this study, we screened for novel genetic markers using comparative genomics and developed a Vibrio multiplex PCR for the reliable diagnosis of the Vibrio genus and the associated major pathogenic Vibrio species. A total of 30 Vibrio genome sequences were subjected to comparative genomics, and specific genes of the Vibrio genus and five major pathogenic Vibrio species were screened. The designed primer sets from the screened genes were evaluated by single PCR using DNAs from various Vibrio spp. and other non-Vibrio bacterial strains. A sextuplet multiplex PCR using six primer sets was developed to enable detection of the Vibrio genus and five pathogenic Vibrio species. The designed primer sets from the screened genes yielded specific diagnostic results for target the Vibrio genus and Vibrio species. The specificity of the developed multiplex PCR was confirmed with various Vibrio and non-Vibrio strains. This Vibrio multiplex PCR was evaluated using 117 Vibrio strains isolated from the south seashore areas in Korea and Vibrio isolates were identified as Vibrio spp., V. parahaemolyticus, V. vulnificus and V. alginolyticus, demonstrating the specificity and discriminative ability of the assay towards Vibrio species. This novel multiplex PCR method could provide reliable and informative identification of the Vibrio genus and major pathogenic Vibrio species in the food safety industry and in early clinical treatment, thereby protecting humans against Vibrio infection.

  18. Computer-designed surgical guide template compared with free-hand operation for mesiodens extraction in premaxilla using "trapdoor" method.

    Science.gov (United States)

    Hu, Ying Kai; Xie, Qian Yang; Yang, Chi; Xu, Guang Zhou

    2017-06-01

    The aim of this study was to introduce a novel method of mesiodens extraction using a vascularized pedicled bone flap by piezosurgery and to compare the differences between a computer-aided design surgical guide template and free-hand operation.A total of 8 patients with mesiodens, 4 with a surgical guide (group I), and 4 without it (group II) were included in the study. The surgical design was to construct a trapdoor pedicle on the superior mucoperiosteal attachment with application of piezosurgery. The bone lid was repositioned after mesiodens extraction. Group I patients underwent surgeries based on the preoperative planning with surgical guide templates, while group II patients underwent free-hand operation. The outcome variables were success rate, intraoperative time, anterior nasal spine (ANS) position, changes of nasolabial angle (NLA), and major complications. Data from the 2 groups were compared by SPSS 17.0, using Wilcoxon test.The operative time was significantly shorter in group I patients. All the mesiodentes were extracted successfully and no obvious differences of preoperative and postoperative ANS position and NLA value were found in both groups. The patients were all recovered uneventfully.Surgical guide templates can enhance clinical accuracy and reduce operative time by facilitating accurate osteotomies.

  19. Tools Lighten Designs, Maintain Structural Integrity

    Science.gov (United States)

    2009-01-01

    Collier Research Corporation of Hampton, Virginia, licensed software developed at Langley Research Center to reduce design weight through the use of composite materials. The first license of NASA-developed software, it has now been used in everything from designing next-generation cargo containers, to airframes, rocket engines, ship hulls, and train bodies. The company now has sales of the NASA-derived software topping $4 million a year and has recently received several Small Business Innovation Research (SBIR) contracts to apply its software to nearly all aspects of the new Orion crew capsule design.

  20. The cost effectiveness of an early transition from hospital to nursing home for stroke patients: design of a comparative study

    Directory of Open Access Journals (Sweden)

    Limburg Martien

    2010-05-01

    Full Text Available Abstract Background As the incidence of stroke has increased, its impact on society has increased accordingly, while it continues to have a major impact on the individual. New strategies to further improve the quality, efficiency and logistics of stroke services are necessary. Early discharge from hospital to a nursing home with an adequate rehabilitation programme could help to optimise integrated care for stroke patients. The objective is to describe the design of a non-randomised comparative study evaluating early admission to a nursing home, with multidisciplinary assessment, for stroke patients. The study is comprised of an effect evaluation, an economic evaluation and a process evaluation. Methods/design The design involves a non-randomised comparative trial for two groups. Participants are followed for 6 months from the time of stroke. The intervention consists of a redesigned care pathway for stroke patients. In this care pathway, patients are discharged from hospital to a nursing home within 5 days, in comparison with 12 days in the usual situation. In the nursing home a structured assessment takes place, aimed at planning adequate rehabilitation. People in the control group receive the usual care. The main outcome measures of the effect evaluation are quality of life and daily functioning. In addition, an economic evaluation will be performed from a societal perspective. A process evaluation will be carried out to evaluate the feasibility of the intervention as well as the experiences and opinions of patients and professionals. Discussion The results of this study will provide information about the cost effectiveness of the intervention and its effects on clinical outcomes and quality of life. Relevant strengths and weaknesses of the study are addressed in this article. Trial registration Current Controlled Trails ISRCTN58135104

  1. Randomized cluster crossover trials for reliable, efficient, comparative effectiveness testing: design of the Prevention of Arrhythmia Device Infection Trial (PADIT).

    Science.gov (United States)

    Connolly, Stuart J; Philippon, Francois; Longtin, Yves; Casanova, Amparo; Birnie, David H; Exner, Derek V; Dorian, Paul; Prakash, Ratika; Alings, Marco; Krahn, Andrew D

    2013-06-01

    Randomized clinical trials are a major advance in clinical research methodology. However, there are myriad important questions about the effectiveness of treatments used in daily practice that are not informed by the results of randomized trials. This is in part because of important limitations inherent in the methodology of randomized efficacy trials which are performed with tight control of inclusion, exclusion, treatment, and follow-up. This approach enhances evaluation of clinical efficacy (performance in controlled situations) but increases complexity and is not well suited to test clinical effectiveness (performance under conditions of actual use). The cluster crossover trial is a new concept for efficient comparative effectiveness testing. Deep tissue infection occurs in 2% of patients after arrhythmia device implantation, usually requires system extraction, and increases mortality. There is variation in antibiotic prophylaxis used to reduce implanted device infections. To efficiently evaluate the comparative effectiveness of antibiotic strategies now in use, we designed a cluster crossover clinical trial, which randomized implanting centres to 1 of 2 prophylactic antibiotic strategies, which became the standard care at the centre for 6 months, followed by crossover to the other strategy, rerandomization, and second crossover. This method greatly reduces trial complexity because it aligns study procedures with usual clinical care and increases generalizability. Pilot studies have tested the feasibility and an 10,800-patient trial, funded by the Canadian Institutes of Health Research, is now under way. The cluster crossover randomized trial design is well suited to efficiently test comparative effectiveness of existing treatments where there is variability of practice, clinical equipoise, and minimal risk.

  2. The "Comparing Approaches" Workshop as an Introduction to Inquiry-Based Learning, Curriculum Design, and the Professional Development Program

    Science.gov (United States)

    Rice, E. L.

    2010-12-01

    The Comparing Approaches to Hands-On Science workshop was developed by the Institute for Inquiry at the Exploratorium and incorporated as a half-day activity into the Center for Adaptive Optics Professional Development Program (PDP) and other teaching venues supported by PDP participants and staff. The Comparing Approaches activity builds upon the common assumption that "hands-on" learning experiences develop deeper and longer-lasting understanding of material. It challenges teacher-participants to reflect on why that is and to consider how hands-on learning is most effectively incorporated into a science curriculum to meet the defined content, scientific process, and attitudinal objectives. I have participated in the Comparing Approaches workshop at several venues and with a variety of roles, and in this paper I describe how the workshop is effective as preparation for exploring the concept of inquiry and inquiry-based learning and as an introduction to "backward" curriculum design and to the PDP as a whole. I discuss challenges I faced as a participant, as a facilitator (instructor) for the activity, and as a discussion leader and provide advice for future implementations of the workshop.

  3. Design of 1-bit and 2-bit magnitude comparators using electro-optic effect in Mach-Zehnder interferometers

    Science.gov (United States)

    Kumar, Santosh; Bisht, Ashish; Singh, Gurdeep; Choudhary, Kuldeep; Raina, K. K.; Amphawan, Angela

    2015-12-01

    The Mach-Zehnder interferometer (MZI) structures collectively show powerful capability in switching an input optical signal to a desired output port from a collection of output ports. Hence, it is possible to construct complex optical combinational digital circuits using the electro-optic effect constituting MZI structure as a basic building block. Optical switches have been designed for 1-bit and 2-bit magnitude comparators based on electro-optic effect using Mach-Zehnder interferometers. The paper constitutes a mathematical description of the proposed device and thereafter simulation using MATLAB. Analysis of some factors influencing the performances of proposed device has been discussed properly. The study is verified using beam propagation method.

  4. Design and optimisation of low heat load liquid helium cryostat to house cryogenic current comparator in antiproton decelerator at CERN

    Science.gov (United States)

    Lees, A.; Koettig, T.; Fernandes, M.; Tan, J.

    2017-02-01

    The Cryogenic Current Comparator (CCC) is installed in the low-energy Antiproton Decelerator (AD) at CERN to make an absolute measurement of the beam intensity. Operating below 4.2 K, it is based on a superconducting quantum interference device (SQUID) and employs a superconducting niobium shield to supress magnetic field components not linked to the beam current. The AD contains no permanent cryogenic infrastructure so the local continuous liquefaction of helium using a pulse-tube is required; limiting the available cooling power to 0.69 W at 4.2K. Due to the sensitivity of the SQUID to variations in magnetic fields, the CCC is highly sensitive to mechanical vibration which is limited to a minimum by the support systems of the cryostat. This article presents the cooling system of the cryostat and discusses the design challenges overcome to minimise the transmission of vibration to the CCC while operating within the cryogenic limits imposed by the cooling system.

  5. Assessing the comparative effectiveness of Tai Chi versus physical therapy for knee osteoarthritis: design and rationale for a randomized trial.

    Science.gov (United States)

    Wang, Chenchen; Iversen, Maura D; McAlindon, Timothy; Harvey, William F; Wong, John B; Fielding, Roger A; Driban, Jeffrey B; Price, Lori Lyn; Rones, Ramel; Gamache, Tressa; Schmid, Christopher H

    2014-09-08

    Knee osteoarthritis (OA) causes pain and long-term disability with annual healthcare costs exceeding $185 billion in the United States. Few medical remedies effectively influence the course of the disease. Finding effective treatments to maintain function and quality of life in patients with knee OA is one of the national priorities identified by the Institute of Medicine. We are currently conducting the first comparative effectiveness and cost-effectiveness randomized trial of Tai Chi versus a physical-therapy regimen in a sample of patients with symptomatic and radiographically confirmed knee OA. This article describes the design and conduct of this trial. A single-center, 52-week, comparative effectiveness randomized controlled trial of Tai Chi versus a standardized physical-therapy regimen is being conducted at an urban tertiary medical center in Boston, Massachusetts. The study population consists of adults ≥ 40 years of age with symptomatic and radiographic knee OA (American College of Rheumatology criteria). Participants are randomly allocated to either 12 weeks of Tai Chi (2x/week) or Physical Therapy (2x/week for 6 weeks, followed by 6 weeks of rigorously monitored home exercise). The primary outcome measure is pain (Western Ontario and McMaster Universities WOMAC) subscale at 12 weeks. Secondary outcomes include WOMAC stkiffness and function domain scores, lower extremity strength and power, functional balance, physical performance tests, psychological and psychosocial functioning, durability effects, health related quality of life, and healthcare utilization at 12, 24 and 52 weeks. This study will be the first randomized comparative-effectiveness and cost-effectiveness trial of Tai Chi versus Physical Therapy in a large symptomatic knee OA population with long-term follow up. We present here a robust and well-designed randomized comparative-effectiveness trial that also explores multiple outcomes to elucidate the potential mechanisms of mind

  6. Protocol design and current status of CLIVIT: a randomized controlled multicenter relevance trial comparing clips versus ligatures in thyroid surgery

    Directory of Open Access Journals (Sweden)

    Wollermann C

    2006-09-01

    Full Text Available Abstract Background Annually, more than 90000 surgical procedures of the thyroid gland are performed in Germany. Strategies aimed at reducing the duration of the surgical procedure are relevant to patients and the health care system especially in the context of reducing costs. However, new techniques for quick and safe hemostasis have to be tested in clinically relevance randomized controlled trials before a general recommendation can be given. The current standard for occlusion of blood vessels in thyroid surgery is ligatures. Vascular clips may be a safe alternative but have not been investigated in a large RCT. Methods/design CLIVIT (Clips versus Ligatures in Thyroid Surgery is an investigator initiated, multicenter, patient-blinded, two-group parallel relevance randomized controlled trial designed by the Study Center of the German Surgical Society. Patients scheduled for elective resection of at least two third of the gland for benign thyroid disease are eligible for participation. After surgical exploration patients are randomized intraoperatively into either the conventional ligature group, or into the clip group. The primary objective is to test for a relevant reduction in operating time (at least 15 min when using the clip technique. Since April 2004, 121 of the totally required 420 patients were randomized in five centers. Discussion As in all trials the different forms of bias have to be considered, and as in this case, a surgical trial, the role of surgical expertise plays a key role, and will be documented and analyzed separately. This is the first randomized controlled multicenter relevance trial to compare different vessel occlusion techniques in thyroid surgery with adequate power and other detailed information about the design as well as framework. If significant, the results might be generalized and may change the current surgical practice.

  7. A comparative study of the efficacy of four different bristle designs of tooth brushes in plaque removal

    Directory of Open Access Journals (Sweden)

    Sripriya N

    2007-06-01

    Full Text Available Background : The aim of the study was to compare the efficacy of four most commonly used bristle designs of toothbrushes in plaque removal. Materials and Methods : The study was a randomized 4 cell, examiner blind cross-over design assessing the plaque removal efficacy of all four brushes on a single occasion. Sixteen subjects aged 14-15 years participated in the study. On day 1 of each test period, the subjects were rendered plaque free and were asked to suspend oral hygiene practices for 24 hours. On day 2, the subjects were scored for plaque prior to brushing using the Turesky-Gilmore modification of Quigley-Hein plaque index. The subjects then brushed with the allocated toothbrush for 2 minutes and the post-brushing plaque scores were assessed. A wash-out period of 4 days was allowed between the test periods. Results : All the brushes showed a significant reduction in the post-brushing plaque scores ( p < 0.001. The mean reduction in the plaque scores for all the brushes was around 53%. The percentage plaque reduction was greater in the anterior surface than the posterior surface (59.6 ± 7.45% vs. 49.83 ± 4.35%. The percentage plaque reductions in the upper, lower, buccal and lingual surfaces were similar. No significant difference in the reduction of plaque scores between the four brushes was seen. Conclusion : The data derived from the study supports the contention of many researchers that there is no single superior design of manual toothbrush. Though minor and some site differences in favor of the brushes were seen, they were not statistically significant.

  8. The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) program : Bell Helicopter Textron accomplishments

    Science.gov (United States)

    Cronkhite, James D.

    1993-01-01

    Accurate vibration prediction for helicopter airframes is needed to 'fly from the drawing board' without costly development testing to solve vibration problems. The principal analytical tool for vibration prediction within the U.S. helicopter industry is the NASTRAN finite element analysis. Under the NASA DAMVIBS research program, Bell conducted NASTRAN modeling, ground vibration testing, and correlations of both metallic (AH-1G) and composite (ACAP) airframes. The objectives of the program were to assess NASTRAN airframe vibration correlations, to investigate contributors to poor agreement, and to improve modeling techniques. In the past, there has been low confidence in higher frequency vibration prediction for helicopters that have multibladed rotors (three or more blades) with predominant excitation frequencies typically above 15 Hz. Bell's findings under the DAMVIBS program, discussed in this paper, included the following: (1) accuracy of finite element models (FEM) for composite and metallic airframes generally were found to be comparable; (2) more detail is needed in the FEM to improve higher frequency prediction; (3) secondary structure not normally included in the FEM can provide significant stiffening; (4) damping can significantly affect phase response at higher frequencies; and (5) future work is needed in the areas of determination of rotor-induced vibratory loads and optimization.

  9. Carborane clusters in computational drug design: a comparative docking evaluation using AutoDock, FlexX, Glide, and Surflex.

    Science.gov (United States)

    Tiwari, Rohit; Mahasenan, Kiran; Pavlovicz, Ryan; Li, Chenglong; Tjarks, Werner

    2009-06-01

    Compounds containing boron atoms play increasingly important roles in the therapy and diagnosis of various diseases, particularly cancer. However, computational drug design of boron-containing therapeutics and diagnostics is hampered by the fact that many software packages used for this purpose lack parameters for all or part of the various types of boron atoms. In the present paper, we describe simple and efficient strategies to overcome this problem, which are based on the replacement of boron atom types with carbon atom types. The developed methods were validated by docking closo- and nido-carboranyl antifolates into the active site of a human dihydrofolate reductase (hDHFR) using AutoDock, Glide, FlexX, and Surflex and comparing the obtained docking poses with the poses of their counterparts in the original hDHFR-carboranyl antifolate crystal structures. Under optimized conditions, AutoDock and Glide were equally good in docking of the closo-carboranyl antifolates followed by Surflex and FlexX, whereas Autodock, Glide, and Surflex proved to be comparably efficient in the docking of nido-carboranyl antifolates followed by FlexX. Differences in geometries and partial atom charges in the structures of the carboranyl antifolates resulting from different data sources and/or optimization methods did not impact the docking performances of AutoDock or Glide significantly. Binding energies predicted by all four programs were in accordance with experimental data.

  10. Design-Oriented Analysis of Aircraft Fuselage Structures

    Science.gov (United States)

    Giles, Gary L.

    1998-01-01

    A design-oriented analysis capability for aircraft fuselage structures that utilizes equivalent plate methodology is described. This new capability is implemented as an addition to the existing wing analysis procedure in the Equivalent Laminated Plate Solution (ELAPS) computer code. The wing and fuselage analyses are combined to model entire airframes. The paper focuses on the fuselage model definition, the associated analytical formulation and the approach used to couple the wing and fuselage analyses. The modeling approach used to minimize the amount of preparation of input data by the user and to facilitate the making of design changes is described. The fuselage analysis is based on ring and shell equations but the procedure is formulated to be analogous to that used for plates in order to take advantage of the existing code in ELAPS. Connector springs are used to couple the wing and fuselage models. Typical fuselage analysis results are presented for two analytical models. Results for a ring-stiffened cylinder model are compared with results from conventional finite-element analyses to assess the accuracy of this new analysis capability. The connection of plate and ring segments is demonstrated using a second model that is representative of the wing structure for a channel-wing aircraft configuration.

  11. Structural design and analysis of a Mach zero to five turbo-ramjet system

    Science.gov (United States)

    Spoth, Kevin A.; Moses, Paul L.

    1993-01-01

    The paper discusses the structural design and analysis of a Mach zero to five turbo-ramjet propulsion system for a Mach five waverider-derived cruise vehicle. The level of analysis detail necessary for a credible conceptual design is shown. The results of a finite-element failure mode sizing analysis for the engine primary structure is presented. The importance of engine/airframe integration is also discussed.

  12. Comparing Dutch Case management care models for people with dementia and their caregivers: The design of the COMPAS study

    Directory of Open Access Journals (Sweden)

    MacNeil Vroomen Janet

    2012-05-01

    Full Text Available Abstract Background Dementia care in the Netherlands is shifting from fragmented, ad hoc care to more coordinated and personalised care. Case management contributes to this shift. The linkage model and a combination of intensive case management and joint agency care models were selected based on their emerging prominence in the Netherlands. It is unclear if these different forms of case management are more effective than usual care in improving or preserving the functioning and well-being at the patient and caregiver level and at the societal cost. The objective of this article is to describe the design of a study comparing these two case management care models against usual care. Clinical and cost outcomes are investigated while care processes and the facilitators and barriers for implementation of these models are considered. Design Mixed methods include a prospective, observational, controlled, cohort study among persons with dementia and their primary informal caregiver in regions of the Netherlands with and without case management including a qualitative process evaluation. Inclusion criteria for the cohort study are: community-dwelling individuals with a dementia diagnosis who are not terminally-ill or anticipate admission to a nursing home within 6 months and with an informal caregiver who speaks fluent Dutch. Person with dementia-informal caregiver dyads are followed for two years. The primary outcome measure is the Neuropsychiatric Inventory for the people with dementia and the General Health Questionnaire for their caregivers. Secondary outcomes include: quality of life and needs assessment in both persons with dementia and caregivers, activity of daily living, competence of care, and number of crises. Costs are measured from a societal perspective using cost diaries. Process indicators measure the quality of care from the participant’s perspective. The qualitative study uses purposive sampling methods to ensure a wide variation of

  13. Design

    DEFF Research Database (Denmark)

    Volf, Mette

    This publication is unique in its demystification and operationalization of the complex and elusive nature of the design process. The publication portrays the designer’s daily work and the creative process, which the designer is a part of. Apart from displaying the designer’s work methods...... and design parameters, the publication shows examples from renowned Danish design firms. Through these examples the reader gets an insight into the designer’s reality....

  14. Comparative Study Between the Two Experimental Design Approaches Taguchi and Traditional in Presence of Control by Control Interactions

    OpenAIRE

    Arias-Nava Elías Heriberto; Ríos-Lira Armando Javier; Vázquez-López José Antonio; Pérez-González Russell

    2015-01-01

    Design of experiments plays an important role in the field of creating and innovating process and products directly in manufacturing and improving areas. There are several areas into designs of experiments; robust design is one of them. Robust parameter design is a principle that emphasize in products creation through a correct selection of values called “control” which make a product robust to the variability by the noise introducing by another factors known as “noise” factors. This article ...

  15. Sources of variability and comparability between salmonid stomach contents and isotopic analyses: study design lessons and recommendations

    Science.gov (United States)

    Vinson, M.R.; Budy, P.

    2011-01-01

    We compared sources of variability and cost in paired stomach content and stable isotope samples from three salmonid species collected in September 2001–2005 and describe the relative information provided by each method in terms of measuring diet overlap and food web study design. Based on diet analyses, diet overlap among brown trout, rainbow trout, and mountain whitefish was high, and we observed little variation in diets among years. In contrast, for sample sizes n ≥ 25, 95% confidence interval (CI) around mean δ15Ν and δ13C for the three target species did not overlap, and species, year, and fish size effects were significantly different, implying that these species likely consumed similar prey but in different proportions. Stable isotope processing costs were US$12 per sample, while stomach content analysis costs averaged US$25.49 ± $2.91 (95% CI) and ranged from US$1.50 for an empty stomach to US$291.50 for a sample with 2330 items. Precision in both δ15Ν and δ13C and mean diet overlap values based on stomach contents increased considerably up to a sample size of n = 10 and plateaued around n = 25, with little further increase in precision.

  16. Newspaper Articles Related to the Not Criminally Responsible on Account of Mental Disorder (NCRMD) Designation: A Comparative Analysis.

    Science.gov (United States)

    Whitley, Rob; Wang, JiaWei; Carmichael, Victoria; Wellen, Ruth

    2017-10-01

    The not criminally responsible on account of mental disorder (NCRMD) designation remains widely misunderstood by the public. Such misunderstandings may also be reflected in the media. As such, the aim of this study is to conduct a preliminary examination of the tone and content of recent Canadian newspaper articles where NCRMD is a major theme, comparing these to generic articles about mental illness. Articles about mental illness were gathered from major Canadian newspapers. These were then divided into two categories: 1) articles where NCRMD was a major theme and 2) articles where NCRMD was not a major theme. Articles were then coded for the presence or absence of 1) a negative tone, 2) stigmatising tone/content, 3) recovery/rehabilitation as a theme, and 4) shortage of resources/poor quality of care as a theme. The retrieval strategy resulted in 940 articles. Fourteen percent ( n = 131) of all articles had NCRMD as a major theme. In comparison to generic articles about mental illness, articles with NCRMD as a major theme were significantly more likely to have a negative tone ( P < 0.001) and stigmatising tone/content ( P < 0.001) and significantly less likely to have recovery/rehabilitation ( P < 0.001) or shortage of resources/poor quality of care as a theme ( P < 0.001). Articles with NCRMD as a theme were overwhelmingly negative and almost never focused on recovery or rehabilitation, in stark comparison to generic articles about mental illness.

  17. Implementation fidelity of a program designed to promote personal and social responsibility through physical education: a comparative case study.

    Science.gov (United States)

    Pascual, Carmina; Escartí, Amparo; Llopis, Ramon; Gutíerrez, Melchor; Marín, Diana; Wright, Paul M

    2011-09-01

    The purpose of this qualitative comparative case study was to examine the implementation fidelity of a program designed to deliver the Teaching Personal and Social Responsibility (TPSR) model (Hellison, 2003) through physical education and its relationship with short-term outcomes for elementary school students. The research questions were: (a) was the program implemented with fidelity, and (b) did better fidelity yield better student outcomes. Thus, we conducted a study on the implementation process used by two teachers who delivered the same program in two physical education classes in two different elementary schools in Spain. Data sources included observations and interviews with teachers and nonparticipant observers. Findings indicated that fidelity of implementation in Case 1 was higher and most children in those classes acquired the first three of five TPSR responsibility levels. Implementation fidelity in Case 2 was weaker and achievement of responsibility goals was minimal (only the first of five levels) and less stable for those students. This study is the first to directly examine the connection between TPSR implementation fidelity and student outcomes.

  18. A Biomechanical Study Comparing Helical Blade with Screw Design for Sliding Hip Fixations of Unstable Intertrochanteric Fractures

    Directory of Open Access Journals (Sweden)

    Qiang Luo

    2013-01-01

    Full Text Available Dynamic hip screw (DHS is a well-established conventional implant for treating intertrochanteric fracture. However, revision surgery sometimes still occurs due to the cutting out of implants. A helical blade instead of threaded screw (DHS blade was designed to improve the fixation power of the osteoporotic intertrochanteric fracture. In this study, the biomechanical properties of DHS blade compared to the conventional DHS were evaluated using an unstable AO/OTA 31-A2 intertrochanteric fracture model. Fifty synthetic proximal femoral bone models with such configuration were fixed with DHS and DHS blade in five different positions: centre-centre (CC, superior-centre (SC, inferior-center (IC, centre-anterior (CA, and centre-posterior (CP. All models had undergone mechanical compression test, and the vertical and rotational displacements were recorded. The results showed that DHS blade had less vertical or rotational displacement than the conventional DHS in CC, CA, and IC positions. The greatest vertical and rotational displacements were found at CP position in both groups. Overall speaking, DHS blade was superior in resisting vertical or rotational displacement in comparison to conventional DHS, and the centre-posterior position had the poorest performance in both groups.

  19. Design and comparative analysis of 10 MW class superconducting wind power generators according to different types of superconducting wires

    Science.gov (United States)

    Sung, Hae-Jin; Kim, Gyeong-Hun; Kim, Kwangmin; Park, Minwon; Yu, In-Keun; Kim, Jong-Yul

    2013-11-01

    Wind turbine concepts can be classified into the geared type and the gearless type. The gearless type wind turbine is more attractive due to advantages of simplified drive train and increased energy yield, and higher reliability because the gearbox is omitted. In addition, this type resolves the weight issue of the wind turbine with the light weight of gearbox. However, because of the low speed operation, this type has disadvantage such as the large diameter and heavy weight of generator. Super-Conducting (SC) wind power generator can reduce the weight and volume of a wind power system. Properties of superconducting wire are very different from each company. This paper considers the design and comparative analysis of 10 MW class SC wind power generators according to different types of SC wires. Super-Conducting Synchronous Generators (SCSGs) using YBCO and Bi-2223 wires are optimized by an optimal method. The magnetic characteristics of the SCSGs are investigated using the finite elements method program. The optimized specifications of the SCSGs are discussed in detail, and the optimization processes can be used effectively to develop large scale wind power generation systems.

  20. Comparative Analysis of Recruitment Qualifications of Industrial Designers in Turkey through Undergraduate Education Programs and Online Recruitment Resources

    Science.gov (United States)

    Erkarslan, Onder; Kaya, Nazife A.; Dilek, Ozgun

    2013-01-01

    Although the term "industrial designer" is a well known title, the understanding of industrial design as a profession is still unclear, as evidenced by its application in the sector. In light of this, schools of industrial design should, despite the immense contributions to the sector made by their past graduates, continuously revise…

  1. Comparative Analysis of Recruitment Qualifications of Industrial Designers in Turkey through Undergraduate Education Programs and Online Recruitment Resources

    Science.gov (United States)

    Erkarslan, Onder; Kaya, Nazife A.; Dilek, Ozgun

    2013-01-01

    Although the term "industrial designer" is a well known title, the understanding of industrial design as a profession is still unclear, as evidenced by its application in the sector. In light of this, schools of industrial design should, despite the immense contributions to the sector made by their past graduates, continuously revise their…

  2. Comparative Analysis of Recruitment Qualifications of Industrial Designers in Turkey through Undergraduate Education Programs and Online Recruitment Resources

    Science.gov (United States)

    Erkarslan, Onder; Kaya, Nazife A.; Dilek, Ozgun

    2013-01-01

    Although the term "industrial designer" is a well known title, the understanding of industrial design as a profession is still unclear, as evidenced by its application in the sector. In light of this, schools of industrial design should, despite the immense contributions to the sector made by their past graduates, continuously revise…

  3. Comparing Inference Approaches for RD Designs: A Reexamination of the Effect of Head Start on Child Mortality

    Science.gov (United States)

    Cattaneo, Matias D.; Titiunik, Rocío; Vazquez-Bare, Gonzalo

    2017-01-01

    The regression discontinuity (RD) design is a popular quasi-experimental design for causal inference and policy evaluation. The most common inference approaches in RD designs employ "flexible" parametric and nonparametric local polynomial methods, which rely on extrapolation and large-sample approximations of conditional expectations…

  4. Comparing State-of-the-Art Evolutionary Multi-Objective Algorithms for Long-Term Groundwater Monitoring Design

    Science.gov (United States)

    Reed, P. M.; Kollat, J. B.

    2005-12-01

    This study demonstrates the effectiveness of a modified version of Deb's Non-Dominated Sorted Genetic Algorithm II (NSGAII), which the authors have named the Epsilon-Dominance Non-Dominated Sorted Genetic Algorithm II (Epsilon-NSGAII), at solving a four objective long-term groundwater monitoring (LTM) design test case. The Epsilon-NSGAII incorporates prior theoretical competent evolutionary algorithm (EA) design concepts and epsilon-dominance archiving to improve the original NSGAII's efficiency, reliability, and ease-of-use. This algorithm eliminates much of the traditional trial-and-error parameterization associated with evolutionary multi-objective optimization (EMO) through epsilon-dominance archiving, dynamic population sizing, and automatic termination. The effectiveness and reliability of the new algorithm is compared to the original NSGAII as well as two other benchmark multi-objective evolutionary algorithms (MOEAs), the Epsilon-Dominance Multi-Objective Evolutionary Algorithm (Epsilon-MOEA) and the Strength Pareto Evolutionary Algorithm 2 (SPEA2). These MOEAs have been selected because they have been demonstrated to be highly effective at solving numerous multi-objective problems. The results presented in this study indicate superior performance of the Epsilon-NSGAII in terms of the hypervolume indicator, unary Epsilon-indicator, and first-order empirical attainment function metrics. In addition, the runtime metric results indicate that the diversity and convergence dynamics of the Epsilon-NSGAII are competitive to superior relative to the SPEA2, with both algorithms greatly outperforming the NSGAII and Epsilon-MOEA in terms of these metrics. The improvements in performance of the Epsilon-NSGAII over its parent algorithm the NSGAII demonstrate that the application of Epsilon-dominance archiving, dynamic population sizing with archive injection, and automatic termination greatly improve algorithm efficiency and reliability. In addition, the usability of

  5. Design and methods for a randomized clinical trial comparing three outreach efforts to improve screening mammography adherence

    Directory of Open Access Journals (Sweden)

    Reed George

    2011-06-01

    Full Text Available Abstract Background Despite the demonstrated need to increase screening mammography utilization and strong evidence that mail and telephone outreach to women can increase screening, most managed care organizations have not adopted comprehensive outreach programs. The uncertainty about optimum strategies and cost effectiveness have retarded widespread acceptance. While 70% of women report getting a mammogram within the prior 2 years, repeat mammography rates are less than 50%. This 5-year study is conducted though a Central Massachusetts healthcare plan and affiliated clinic. All womenhave adequate health insurance to cover the test. Methods/Design This randomized study compares 3 arms: reminder letter alone; reminder letter plus reminder call; reminder letter plus a second reminder and booklet plus a counselor call. All calls provide women with the opportunity to schedule a mammogram in a reasonable time. The invention period will span 4 years and include repeat attempts. The counselor arm is designed to educate, motivate and counsel women in an effort to alleviate PCP burden. All women who have been in the healthcare plan for 24 months and who have a current primary care provider (PCP and who are aged 51-84 are randomized to 1 of 3 arms. Interventions are limited to women who become ≥18 months from a prior mammogram. Women and their physicians may opt out of the intervention study. Measurement of completed mammograms will use plan billing records and clinic electronic records. The primary outcome is the proportion of women continuously enrolled for ≥24 months who have had ≥1 mammogram in the last 24 months. Secondary outcomes include the number of women who need repeat interventions. The cost effectiveness analysis will measure all costs from the provider perspective. Discussion So far, 18,509 women aged 51-84 have been enrolled into our tracking database and were randomized into one of three arms. At baseline, 5,223 women were eligible

  6. Designing for Damage: Robust Flight Control Design using Sliding Mode Techniques

    Science.gov (United States)

    Vetter, T. K.; Wells, S. R.; Hess, Ronald A.; Bacon, Barton (Technical Monitor); Davidson, John (Technical Monitor)

    2002-01-01

    A brief review of sliding model control is undertaken, with particular emphasis upon the effects of neglected parasitic dynamics. Sliding model control design is interpreted in the frequency domain. The inclusion of asymptotic observers and control 'hedging' is shown to reduce the effects of neglected parasitic dynamics. An investigation into the application of observer-based sliding mode control to the robust longitudinal control of a highly unstable is described. The sliding mode controller is shown to exhibit stability and performance robustness superior to that of a classical loop-shaped design when significant changes in vehicle and actuator dynamics are employed to model airframe damage.

  7. Comparing oncology clinical programs by use of innovative designs and expected net present value optimization: Which adaptive approach leads to the best result?

    Science.gov (United States)

    Parke, Tom; Marchenko, Olga; Anisimov, Vladimir; Ivanova, Anastasia; Jennison, Christopher; Perevozskaya, Inna; Song, Guochen

    2017-01-01

    Designing an oncology clinical program is more challenging than designing a single study. The standard approaches have been proven to be not very successful during the last decade; the failure rate of Phase 2 and Phase 3 trials in oncology remains high. Improving a development strategy by applying innovative statistical methods is one of the major objectives of a drug development process. The oncology sub-team on Adaptive Program under the Drug Information Association Adaptive Design Scientific Working Group (DIA ADSWG) evaluated hypothetical oncology programs with two competing treatments and published the work in the Therapeutic Innovation and Regulatory Science journal in January 2014. Five oncology development programs based on different Phase 2 designs, including adaptive designs and a standard two parallel arm Phase 3 design were simulated and compared in terms of the probability of clinical program success and expected net present value (eNPV). In this article, we consider eight Phase2/Phase3 development programs based on selected combinations of five Phase 2 study designs and three Phase 3 study designs. We again used the probability of program success and eNPV to compare simulated programs. For the development strategies, we considered that the eNPV showed robust improvement for each successive strategy, with the highest being for a three-arm response adaptive randomization design in Phase 2 and a group sequential design with 5 analyses in Phase 3.

  8. Sequential cohort design applying propensity score matching to analyze the comparative effectiveness of atorvastatin and simvastatin in preventing cardiovascular events.

    Directory of Open Access Journals (Sweden)

    Arja Helin-Salmivaara

    Full Text Available Sequential cohort design (SCD applying matching for propensity scores (PS in accrual periods has been proposed to mitigate bias caused by channeling when calendar time is a proxy for strong confounders. We studied the channeling of patients according to atorvastatin and simvastatin initiation in Finland, starting from the market introduction of atorvastatin in 1998, and explored the SCD PS approach to analyzing the comparative effectiveness of atorvastatin versus simvastatin in the prevention of cardiovascular events (CVE.Initiators of atorvastatin or simvastatin use in the 45-75-year age range in 1998-2006 were characterized by their propensity of receiving atorvastatin over simvastatin, as estimated for 17 six-month periods. Atorvastatin (10 mg and simvastatin (20 mg initiators were matched 1∶1 on the PS, as estimated for the whole cohort and within each period. Cox regression models were fitted conventionally, and also for the PS matched cohort and the periodically PS matched cohort, to estimate the hazard ratios (HR for CVEs.Atorvastatin (10 mg was associated with a 11%-12% lower incidence of CVE in comparison with simvastatin (20 mg. The HR estimates were the same for a conventional Cox model (0.88, 95% confidence interval 0.85-0.91, for the analysis in which the PS was used to match across all periods and the Cox model was adjusted for strong confounders (0.89, 0.85-0.92, and for the analysis in which PS matching was applied within sequential periods (0.88, 0.84-0.92. The HR from a traditional PS matched analysis was 0.80 (0.77-0.83.The SCD PS approach produced effect estimates similar to those obtained in matching for PS within the whole cohort and adjusting the outcome model for strong confounders, but at the cost of efficiency. A traditional PS matched analysis without further adjustment in the outcome model produced estimates further away from unity.

  9. Comparative Performance Analysis of XOR-XNOR Function Based High-Speed CMOS Full Adder Circuits For Low Voltage VLSI Design

    Directory of Open Access Journals (Sweden)

    Sudarshan Tiwari

    2012-05-01

    Full Text Available This paper presents comparative study of high-speed, low-power and low voltage full adder circuits. Our approach is based on XOR-XNOR design full adder circuits in a single unit. A low power and high performance 9T full adder cell using a design style called “XOR (3T” is discussed. The designed circuit commands a high degree of regularity and symmetric higher density than the conventional CMOS design style as well as it lowers power consumption by using XOR (3T logic circuits. Gate Diffusion Input (GDI technique of low-power digital combinatorial circuit design is also described. This technique helps inreducing the power consumption and the area of digital circuits while maintaining low complexity of logic design. This paper analyses, evaluates and compares the performance of various adder circuits. Severalsimulations conducted using different voltage supplies, load capacitors and temperature variation demonstrate the superiority of the XOR (3T based full adder designs in term of delay, power and powerdelay product (PDP compared to the other full adder circuits. Simulation results illustrate the superiority of the designed adder circuits against the conventional CMOS, TG and Hybrid full adder circuits in terms of power, delay and power delay product (PDP.

  10. Comparative Amino Acids Studies on Phac Synthases and Proteases as Well as Establishing a New Trend in Experimental Design

    Directory of Open Access Journals (Sweden)

    Amro Abd al fattah Amara

    2012-04-01

    Full Text Available ABSTRACT: A question addressed in this study is: why similar enzymes are classified into different subclasses? As an example, PhaC synthases are classified according to four different classes (I, II, III and IV. To answer this question we proposed that besides the catalytic residues, the overall amino acids (AAs present are responsible for the differences observed. The AAs’ composition affects the structure/function/substrate specificity (SFS of these enzymes. The differences between the classes in various PhaC synthases and proteases were analysed to support our argument. Homology and phylogenic tree of some selected PhaC synthases of different strains (representing the four classes were demonstrated. The properties of a specific class of enzyme could not be changed into those of another by changing the catalytic residues. Moreover, these differences could not be detected from the proteins’ 3D structures, despite clear differences at the AAs level. Another question was also addressed: could we benefit from the various existing protein databases in the field of biotechnology? To answer this, we introduced a model for an Experimental Design based on the information in the protein database (for strains available in our lab regarding their ability to degrade castor oil. Two enzymes in the phenol degradation pathway, phenol 2-monooxygenase and catechol 1,2-dioxygenase, and a lipase enzyme were analysed. These enzymes were screened and analysed according to the BLAST-protein database and BRENDA. The comprehensive enzyme information system compared six strains against each other, including: Pseudomonas aeruginosa, Bacillus subtilis, Bacillus pumilus, Bacillus thuringiensis, Bacillus licheniformis, and Geobacillus stearothermophilus. Only P. aeruginosa proved to have the three required enzymes and was suitable for the production of lipases from castor oil (crude castor oil is usually contaminated with phenol as indicated by the databases. In

  11. The use of systematic and heuristic methods in the basic design cycle: A comparative survey of students' method usage

    DEFF Research Database (Denmark)

    Person, O.; Daalhuizen, Jaap; Gattol, V.

    2013-01-01

    In the present paper, we study the reported use of systematic and heuristic methods for 304 students enrolled in a master-level course on design theory and methodology. What to teach design and engineering students about methods is an important topic for discussion. One reason for this is that th......In the present paper, we study the reported use of systematic and heuristic methods for 304 students enrolled in a master-level course on design theory and methodology. What to teach design and engineering students about methods is an important topic for discussion. One reason...... for this is that the experiences of design educators when using methods in their teaching do not always sit well with how methods are portrayed in the literature. Based on self-reports of the students, we study the use of systematic and heuristic methods for the five activities in the basic design cycle: (1) analysis, (2......) synthesis, (3) simulation, (4) evaluation, and (5) decision-making. The results of our study suggest that systematic and heuristic methods fulfil different roles for the students when designing. The students reported to use heuristic methods significantly more for synthesis, while they reported to use...

  12. Design and methods for a randomized clinical trial comparing three outreach efforts to improve screening mammography adherence.

    Science.gov (United States)

    Costanza, Mary E; Luckmann, Roger; White, Mary Jo; Rosal, Milagros C; Cranos, Caroline; Reed, George; Clark, Robin; Sama, Susan; Yood, Robert

    2011-06-03

    Despite the demonstrated need to increase screening mammography utilization and strong evidence that mail and telephone outreach to women can increase screening, most managed care organizations have not adopted comprehensive outreach programs. The uncertainty about optimum strategies and cost effectiveness have retarded widespread acceptance. While 70% of women report getting a mammogram within the prior 2 years, repeat mammography rates are less than 50%. This 5-year study is conducted though a Central Massachusetts healthcare plan and affiliated clinic. All women have adequate health insurance to cover the test. This randomized study compares 3 arms: reminder letter alone; reminder letter plus reminder call; reminder letter plus a second reminder and booklet plus a counselor call. All calls provide women with the opportunity to schedule a mammogram in a reasonable time. The invention period will span 4 years and include repeat attempts. The counselor arm is designed to educate, motivate and counsel women in an effort to alleviate PCP burden.All women who have been in the healthcare plan for 24 months and who have a current primary care provider (PCP) and who are aged 51-84 are randomized to 1 of 3 arms. Interventions are limited to women who become ≥ 18 months from a prior mammogram. Women and their physicians may opt out of the intervention study.Measurement of completed mammograms will use plan billing records and clinic electronic records. The primary outcome is the proportion of women continuously enrolled for ≥ 24 months who have had ≥ 1 mammogram in the last 24 months. Secondary outcomes include the number of women who need repeat interventions. The cost effectiveness analysis will measure all costs from the provider perspective. So far, 18,509 women aged 51-84 have been enrolled into our tracking database and were randomized into one of three arms. At baseline, 5,223 women were eligible for an intervention. We anticipate that the outcome will provide

  13. In Comparative Analysis for Fuel Burnup of Fuel Assembly Designs for the 300 kW Small Medical Reactor

    Science.gov (United States)

    Sambuu, Odmaa; Nanzad, Norov

    2009-03-01

    A 300 kW small medical reactor was designed to be used for boron neutron capture therapy (BNCT) at KAIST in 1996 [1]. In this paper, analysis for the core life cycle of the original design of the BNCT facility and modifications of the fuel assembly configuration and enrichment to get a proper life cycle were performed and a criticality, neutron flux distribution and fuel burnup calculations were carried out.

  14. Design and Performance of the NASA SCEPTOR Distributed Electric Propulsion Flight Demonstrator

    Science.gov (United States)

    Borer, Nicholas K.; Patterson, Michael D.; Viken, Jeffrey K.; Moore, Mark D.; Clarke, Sean; Redifer, Matthew E.; Christie, Robert J.; Stoll, Alex M.; Dubois, Arthur; Bevirt, JoeBen; hide

    2016-01-01

    Distributed Electric Propulsion (DEP) technology uses multiple propulsors driven by electric motors distributed about the airframe to yield beneficial aerodynamic-propulsion interaction. The NASA SCEPTOR flight demonstration project will retrofit an existing internal combustion engine-powered light aircraft with two types of DEP: small "high-lift" propellers distributed along the leading edge of the wing which accelerate the flow over the wing at low speeds, and larger cruise propellers co-located with each wingtip for primary propulsive power. The updated high-lift system enables a 2.5x reduction in wing area as compared to the original aircraft, reducing drag at cruise and shifting the velocity for maximum lift-to-drag ratio to a higher speed, while maintaining low-speed performance. The wingtip-mounted cruise propellers interact with the wingtip vortex, enabling a further efficiency increase that can reduce propulsive power by 10%. A tradespace exploration approach is developed that enables rapid identification of salient trades, and subsequent creation of SCEPTOR demonstrator geometries. These candidates were scrutinized by subject matter experts to identify design preferences that were not modeled during configuration exploration. This exploration and design approach is used to create an aircraft that consumes an estimated 4.8x less energy at the selected cruise point when compared to the original aircraft.

  15. Design

    DEFF Research Database (Denmark)

    Jensen, Ole B.; Pettiway, Keon

    2017-01-01

    by designers, planners, etc. (staging from above) and mobile subjects (staging from below). A research agenda for studying situated practices of mobility and mobilities design is outlined in three directions: foci of studies, methods and approaches, and epistemologies and frames of thinking. Jensen begins...... with a brief description of how movement is studied within social sciences after the “mobilities turn” versus the idea of physical movement in transport geography and engineering. He then explains how “mobilities design” was derived from connections between traffic and architecture. Jensen concludes......In this chapter, Ole B. Jensen takes a situational approach to mobilities to examine how ordinary life activities are structured by technology and design. Using “staging mobilities” as a theoretical approach, Jensen considers mobilities as overlapping, actions, interactions and decisions...

  16. Design

    DEFF Research Database (Denmark)

    Volf, Mette

    Design - proces & metode iBog®  er enestående i sit fokus på afmystificering og operationalisering af designprocessens flygtige og komplekse karakter. Udgivelsen går bag om designerens daglige arbejde og giver et indblik i den kreative skabelsesproces, som designeren er en del af. Udover et bredt...... indblik i designerens arbejdsmetoder og designparametre giver Design - proces & metode en række eksempler fra anerkendte designvirksomheder, der gør det muligt at komme helt tæt på designerens virkelighed....

  17. Design

    Science.gov (United States)

    Buchanan, Richard; Cross, Nigel; Durling, David; Nelson, Harold; Owen, Charles; Valtonen, Anna; Boling, Elizabeth; Gibbons, Andrew; Visscher-Voerman, Irene

    2013-01-01

    Scholars representing the field of design were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might change our understanding. The scholars included Richard Buchanan, Nigel Cross, David Durling, Harold Nelson, Charles Owen, and Anna Valtonen. Scholars…

  18. Design

    Science.gov (United States)

    Buchanan, Richard; Cross, Nigel; Durling, David; Nelson, Harold; Owen, Charles; Valtonen, Anna; Boling, Elizabeth; Gibbons, Andrew; Visscher-Voerman, Irene

    2013-01-01

    Scholars representing the field of design were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might change our understanding. The scholars included Richard Buchanan, Nigel Cross, David Durling, Harold Nelson, Charles Owen, and Anna Valtonen. Scholars…

  19. Is the large simple trial design used for comparative, post-approval safety research? A review of a clinical trials registry and the published literature.

    Science.gov (United States)

    Reynolds, Robert F; Lem, Joanna A; Gatto, Nicolle M; Eng, Sybil M

    2011-10-01

    Post-approval, observational drug safety studies face well known difficulties in controlling for confounding, particularly confounding by indication for drug use. A study design that addresses confounding by indication is the large simple trial (LST). LSTs are characterized by large sample sizes, often in the thousands; broad entry criteria consistent with the approved medication label; randomization based on equipoise, i.e. neither physician nor patient believes that one treatment option is superior; minimal, streamlined data collection requirements; objectively-measured endpoints (e.g. death, hospitalization); and follow-up that minimizes interventions or interference with normal clinical practice. In theory then, the LST is a preferred study design for drug and vaccine safety research because it controls for biases inherent to observational research while still providing results that are generalizable to 'real-world' use. To evaluate whether LSTs are used for comparative safety evaluation and if the design is, in fact, advantageous compared with other designs, we conducted a review of the published literature (1949 through 31 December 2010) and the ClinicalTrials.gov registry (2000 through 31 December 2010). Thirteen ongoing or completed safety LSTs were identified. The design has rarely been used in comparative drug safety research, which is due to the operational, financial and scientific hurdles of implementing the design. The studies that have been completed addressed important clinical questions and, in some cases, led to re-evaluation of medical practice. We conclude the design has demonstrated utility for comparative safety research of medicines and vaccines if the necessary scientific and operational conditions for its use are met.

  20. Comparative socio-technical discourse analysis of Water Sensitive Urban Design for Melbourne, Australia and Copenhagen, Denmark

    DEFF Research Database (Denmark)

    Mo Madsen, Herle; Brown, Rebekah; Elle, Morten

    This paper presents a comparative socio-technical discourse analysis of WUSD for Melbourne and Copenhagen. Despite Melbourne appearing to have progressed further, the technology pathways are very similar, suggesting significant potential for transfer of insights and policy mechanisms. However...

  1. Comparative socio-technical discourse analysis of Water Sensitive Urban Design for Melbourne, Australia and Copenhagen, Denmark

    DEFF Research Database (Denmark)

    Madsen, Herle Mo; Brown, R.; Elle, Morten

    2013-01-01

    This paper presents a comparative socio-technical discourse analysis of WUSD for Melbourne and Copenhagen. Despite Melbourne appearing to have progressed further, the technology pathways are very similar, suggesting significant potential for transfer of insights and policy mechanisms. However...

  2. What's D&T For? Gathering and Comparing the Values of Design and Technology Academics and Trainee Teachers

    Science.gov (United States)

    Hardy, Alison

    2015-01-01

    Some who read and research about Design & Technology (D&T) would say that the concept of value is key to understanding and defining D&T. Closer inspection reveals though that there are two ways in which values are defined in D&T: how values are taught and learnt about in D&T to use them to make judgments in D&T lessons, and…

  3. Evolutionary and Comparative Genomics to Drive Rational Drug Design, with Particular Focus on Neuropeptide Seven-Transmembrane Receptors

    OpenAIRE

    Furlong, Michael; Seong, Jae Young

    2017-01-01

    Seven transmembrane receptors (7TMRs), also known as G protein-coupled receptors, are popular targets of drug development, particularly 7TMR systems that are activated by peptide ligands. Although many pharmaceutical drugs have been discovered via conventional bulk analysis techniques the increasing availability of structural and evolutionary data are facilitating change to rational, targeted drug design. This article discusses the appeal of neuropeptide-7TMR systems as drug targets and provi...

  4. Meta-Analysis of Human Factors Engineering Studies Comparing Individual Differences, Practice Effects and Equipment Design Variations.

    Science.gov (United States)

    1985-02-21

    probably be called Subjects. On the other hand, when using the language of military manpower management -specialists we may employ the terms, People or...to intravenous drugs, brain-damaged patients, dyslexia , and bilinguals. Practice or training variations included backward counting tasks, instructional...1971). Statistical principles in experimental design ( 2nd ed.). New York: McGraw-Hill. *1 /.’.. ’:-71:v-7 Woodson, W. (1955). 100 rules for-improving

  5. Science through Engineering in Elementary School: Comparing Three Enactments of an Engineering-Design-Based Curriculum on the Science of Sound

    Science.gov (United States)

    Wendell, Kristen Bethke

    2011-01-01

    This research illustrates how varying enactments of an engineering-design-based science curriculum shaped the development of students' domain-specific scientific ideas and practices. In this comparative case study rooted in the analytical perspectives of activity theory and learning environments, student and teacher participants in three…

  6. A Multistage Longitudinal Comparative (MLC) Design Stage II: Evaluation of the Changing Lives Program (CLP)--The Possible Selves Questionnaire-Qualitative Extensions (PSQ-QE)

    Science.gov (United States)

    Kortsch, Gabrielle; Kurtines, William M.; Montgomery, Marilyn J.

    2008-01-01

    The study reported in this paper, a Multistage Longitudinal Comparative (MLC) Design Stage II evaluation conducted as a planned preliminary efficacy evaluation (psychometric evaluation of measures, short-term controlled outcome studies, etc.) of the Changing Lives Program (CLP), provided evidence for the reliability and validity of qualitative…

  7. A Multi-Stage Longitudinal Comparative Design Stage II Evaluation of the Changing Lives Program: The Life Course Interview (RDA-LCI)

    Science.gov (United States)

    Arango, Lisa Lewis; Kurtines, William M.; Montgomery, Marilyn J.; Ritchie, Rachel

    2008-01-01

    The study reported in this article, a Multi-Stage Longitudinal Comparative Design Stage II evaluation conducted as a planned preliminary efficacy evaluation (psychometric evaluation of measures, short-term controlled outcome studies, etc.) of the Changing Lives Program (CLP), provided evidence for the reliability and validity of the qualitative…

  8. Research related to improved computer aided design software package. [comparative efficiency of finite, boundary, and hybrid element methods in elastostatics

    Science.gov (United States)

    Walston, W. H., Jr.

    1986-01-01

    The comparative computational efficiencies of the finite element (FEM), boundary element (BEM), and hybrid boundary element-finite element (HVFEM) analysis techniques are evaluated for representative bounded domain interior and unbounded domain exterior problems in elastostatics. Computational efficiency is carefully defined in this study as the computer time required to attain a specified level of solution accuracy. The study found the FEM superior to the BEM for the interior problem, while the reverse was true for the exterior problem. The hybrid analysis technique was found to be comparable or superior to both the FEM and BEM for both the interior and exterior problems.

  9. Green Building between Tradition and Modernity Study Comparative Analysis between Conventional Methods and Updated Styles of Design and Architecture Processors

    Directory of Open Access Journals (Sweden)

    H Elshimy

    2017-03-01

    Full Text Available Green house   concept appeared from the ancient to the modern age ages and there is a tendency to use a traditional architecture with a pristine ecological environment areas and through sophisticated systems arrived to modern systems of the upgraded systems by Treatment architectural achieve environmental   sustainability   in   recent   years,   sustainability concept has become the common interest of numerous disciplines. The reason for this popularity is to perform the sustainable development. The Concept of Green Architecture, also known as "sustainable architecture” or “green house,” is the theory, science and style of buildings designed and constructed in accordance   with environmentally   friendly   principles.   Green house strives to minimize the number of resources consumed in the   building's  construction,   use   and   operation,   as  well  as curtailing  the  harm  done  to  the  environment  through  the emission, pollution and waste of its components.To design, construct, operate and maintain buildings energy, water and new materials are utilized as well as amounts of waste causing negative effects to health and environment is generated. In order to limit these effects and design environmentally sound and resource efficient buildings; "green building systems" must be introduced, clarified, understood and practiced.This paper aims at highlighting these difficult and complex issues of sustainability which encompass the scope of almost every aspect of human life.

  10. A Two-level Optimization Design Approach for Low RCS Airframe Shapes%基于二级优化的低RCS外形设计方法

    Institute of Scientific and Technical Information of China (English)

    胡添元; 余雄庆

    2007-01-01

    针对飞行器外形隐身优化问题,提出了一种流程简单,可同时优化外形轮廓和剖面形状的二级优化方法.这种方法将优化流程分为外形轮廓级和剖面形状级两个层次:外形轮廓级优化任务是将轮廓形状参数传递给剖面形状级,并对外形轮廓进行优化;剖面形状级优化任务是对剖面形状进行优化,并将目标函数值返回外形轮廓级.二级优化的最终结果可获得最优的轮廓形状和剖面形状.以一个具有低RCS特征的飞行器机身为算例,验证了这种二级优化方法的可行性和有效性.

  11. Optimization design and compare of different solar-ground source heat pump system of office building in cold regions

    Science.gov (United States)

    Xie, H.; He, S.; Fu, Y.

    2016-08-01

    This paper presents two different operation modes of Solar-Ground Source Heat Pump System (SGSHP(S)). With the simulation tool TRNSYS, two different SGSHP system models were built to taking simulation. After making analysis and compare of different simulation results, series operation mode was believed to be better than parallel in the target building.

  12. Comparative socio-technical discourse analysis of Water Sensitive Urban Design for Melbourne, Australia and Copenhagen, Denmark

    DEFF Research Database (Denmark)

    Mo Madsen, Herle; Brown, Rebekah; Elle, Morten

    2013-01-01

    This paper presents a comparative socio-technical discourse analysis of WUSD for Melbourne and Copenhagen. Despite Melbourne appearing to have progressed further, the technology pathways are very similar, suggesting significant potential for transfer of insights and policy mechanisms. However, th...

  13. Optimization of the engineering design for the Lansing District Cooling System by comparative analysis of the impact of advanced technologies on a conventional design approach. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    The Lansing Board of Water and Light (LBWL) began investigating development of a cooling district in the Lansing Downtown in 1989 in order to retain and build summer load for its steam utility. A feasibility study was conducted in conjunction with SFT, Inc. and ZBA, Inc. which addressed many factors such as marketability of the product, impact on the summer steam load, distribution system development, system design, probable capital and operating costs, reliability and environmental and other regulatory impacts on a preliminary feasibility basis. The Phase I study completed in September of 1989 provided highly promising results for establishing a District Cooling System (DCS). An existing chilled water production facility owned by the State of Michigan was identified as a potential location for a DCS plant. With these changes a review of the feasibility with a new set of alternatives and sensitivities was evaluated. This enhancement to the Phase I Study was nearing completion when the LBWL in conjunction with Energy, Mines and Resources Canada proposed to conduct the Phase II project in conjunction with DOE. The project was structured to proceed along a dual track to demonstrate the impact of the application of various innovative technologies.

  14. Recommendations and requirements for the design of bioanalytical testing used in comparability studies for biosimilar drug development.

    Science.gov (United States)

    Cai, Xiao-Yan; Gouty, Dominique; Baughman, Sharon; Ramakrishnan, Ms; Cullen, Constance

    2011-03-01

    With the imminent expiry of patents on a number of biological products on the market, the development of biosimilars (or 'follow-on biologics') creates an increasing opportunity in the biotechnology industry. Although general guidelines on the quality and safety of biological products also apply to biosimilars, there is a need to address specific requirements for developing biosimilar drugs. Since it is critical to show comparability of the biosimilar products to their reference (or innovator) products, developing the appropriate bioanalytical methods to support such preclinical and clinical comparability studies is of great importance. The present work recommends the requirements for the development and validation for both pharmacokinetic and immunogenicity assays to support the biosimilar drug development.

  15. Spatial Orientation, Geomedia and Learning: The design of a Comparative Empirical Study. GI_Forum 2013 – Creating the GISociety|

    OpenAIRE

    Kanwischer, Detlef; Niehaus, Engelbert; Groessler, Matthias

    2013-01-01

    Strongly connected to the change in key media from the “Gutenberg-Galaxy” to the “Internet- Galaxy” is also the hope, to break new ground and more successful ways within competence building in the area of spatial orientation. This paper deals with two questions: Which influence on competence building in the area of spatial orientation does the different identification and collecting possibilities within the work with digital geomedia have compared to the traditional work with paper maps? Furt...

  16. Comparative study of singlet oxygen production by photosensitiser dyes encapsulated in silicone: towards rational design of anti-microbial surfaces.

    Science.gov (United States)

    Noimark, Sacha; Salvadori, Enrico; Gómez-Bombarelli, Rafael; MacRobert, Alexander J; Parkin, Ivan P; Kay, Christopher W M

    2016-10-12

    Surfaces with built-in antimicrobial activity have the potential to reduce hospital-acquired infections. One promising strategy is to create functionalised surfaces which, following illumination with visible light, are able to generate singlet oxygen under aerobic conditions. In contrast to antibiotics, the mechanism of bacterial kill by species derived from reactions with singlet oxygen is completely unselective, therefore offering little room for evolutionary adaptation. Here we consider five commercially available organic photosensitiser dyes encapsulated in silicone polymer that show varied antimicrobial activity. We correlate density functional theory calculations with UV-Vis spectroscopy, electron paramagnetic resonance spectroscopy and singlet oxygen production measurements in order to define and test the elements required for efficacious antimicrobial activity. Our approach forms the basis for the rational in silico design and spectroscopic screening of simple and efficient self-sterilising surfaces made from cheap, low toxicity photosensitiser dyes encapsulated in silicone.

  17. Developing a comprehensive and comparative questionnaire for measuring personality in chimpanzees using a simultaneous top-down/bottom-up design.

    Science.gov (United States)

    Freeman, Hani D; Brosnan, Sarah F; Hopper, Lydia M; Lambeth, Susan P; Schapiro, Steven J; Gosling, Samuel D

    2013-10-01

    One effective method for measuring personality in primates is to use personality trait ratings to distill the experience of people familiar with the individual animals. Previous rating instruments were created using either top-down or bottom-up approaches. Top-down approaches, which essentially adapt instruments originally designed for use with another species, can unfortunately lead to the inclusion of traits irrelevant to chimpanzees or fail to include all relevant aspects of chimpanzee personality. Conversely, because bottom-up approaches derive traits specifically for chimpanzees, their unique items may impede comparisons with findings in other studies and other species. To address the limitations of each approach, we developed a new personality rating scale using a combined top-down/bottom-up design. Seventeen raters rated 99 chimpanzees on the new 41-item scale, with all but one item being rated reliably. Principal components analysis, using both varimax and direct oblimin rotations, identified six broad factors. Strong evidence was found for five of the factors (Reactivity/Undependability, Dominance, Openness, Extraversion, and Agreeableness). A sixth factor (Methodical) was offered provisionally until more data are collected. We validated the factors against behavioral data collected independently on the chimpanzees. The five factors demonstrated good evidence for convergent and predictive validity, thereby underscoring the robustness of the factors. Our combined top-down/bottom-up approach provides the most extensive data to date to support the universal existence of these five personality factors in chimpanzees. This framework, which facilitates cross-species comparisons, can also play a vital role in understanding the evolution of personality and can assist with husbandry and welfare efforts.

  18. Impact of an engineering design-based curriculum compared to an inquiry-based curriculum on fifth graders' content learning of simple machines

    Science.gov (United States)

    Marulcu, Ismail; Barnett, Michael

    2016-01-01

    Background: Elementary Science Education is struggling with multiple challenges. National and State test results confirm the need for deeper understanding in elementary science education. Moreover, national policy statements and researchers call for increased exposure to engineering and technology in elementary science education. The basic motivation of this study is to suggest a solution to both improving elementary science education and increasing exposure to engineering and technology in it. Purpose/Hypothesis: This mixed-method study examined the impact of an engineering design-based curriculum compared to an inquiry-based curriculum on fifth graders' content learning of simple machines. We hypothesize that the LEGO-engineering design unit is as successful as the inquiry-based unit in terms of students' science content learning of simple machines. Design/Method: We used a mixed-methods approach to investigate our research questions; we compared the control and the experimental groups' scores from the tests and interviews by using Analysis of Covariance (ANCOVA) and compared each group's pre- and post-scores by using paired t-tests. Results: Our findings from the paired t-tests show that both the experimental and comparison groups significantly improved their scores from the pre-test to post-test on the multiple-choice, open-ended, and interview items. Moreover, ANCOVA results show that students in the experimental group, who learned simple machines with the design-based unit, performed significantly better on the interview questions. Conclusions: Our analyses revealed that the design-based Design a people mover: Simple machines unit was, if not better, as successful as the inquiry-based FOSS Levers and pulleys unit in terms of students' science content learning.

  19. Integrated Impact Indicators (I3) compared with Impact Factors (IFs): An alternative research design with policy implications

    CERN Document Server

    Leydesdorff, Loet

    2011-01-01

    In bibliometrics, the association of "impact" with central-tendency statistics is mistaken. The impact of two collisions is more than the mean or median of the two impacts; impacts add up, and citation curves should therefore be integrated instead of averaged. For example, the journals MIS Quarterly and JASIST differ by a factor of two in terms of their respective impact factors (IF), but the journal with the lower IF has the higher impact. Using percentiles (e.g., top-1%, top-10%, etc.), an integrated impact indicator (I3) can be based on integration of the citation curves after normalization to the same scale. The results across document sets can be compared as percentages of the total impact of a reference set. Total number of citations, however, should not be used instead because the shape of the citation curves is then not appreciated. In addition to comparing I3 with IFs for the journals in two ISI Subject Categories ("Information Science & Library Science" and "Multidisciplinary Sciences"), we show...

  20. Comparative Analysis of Material Criteria in Neighborhood Sustainability Assessment Tools and Urban Design Guidelines: Cases of the UK, the US, Japan, and Korea

    Directory of Open Access Journals (Sweden)

    Jungwon Yoon

    2015-10-01

    Full Text Available Sustainability assessment tools have been developed for building-scale sustainability since the 1990s. Several systems, such as BREEAM (Building Research Establishment Environmental Assessment Methodology, LEED (Leadership in Energy and Environmental Design and CASBEE (Comprehensive Assessment System for Built Environment Efficiency, are widely used and have been upgraded and adapted to large-scale development. BREEAM Communities, LEED Neighborhood Development and CASBEE for Urban Development have been implemented in the UK, the USA and Japan, respectively. As the notion of sustainable urban design has gained more significance, city governments have set their own guidelines for sustainable standards in urban design based on studies of sustainability assessment tools. This study focused on a comparative analysis of the material criteria embedded for sustainable urban design in BREEAM Communities, LEED-ND (Neighborhood Development and CASBEE-UD (Urban Development, and the urban design guidelines recently issued in multiple cities, including London, New York, Tokyo, and Seoul. The top master plans and the supplementary guidelines were analyzed to investigate the detailed material criteria. The study examined the differences in the material assessment criteria, evaluation parameters, and descriptions of the neighborhood sustainability assessment tools and the urban design guidelines. The material criteria was investigated and discussed to summarize the current features and weaknesses as balanced material assessments for sustainable urban development.

  1. How to develop, validate, and compare clinical prediction models involving radiological parameters: Study design and statistical methods

    Energy Technology Data Exchange (ETDEWEB)

    Han, Kyung Hwa; Choi, Byoung Wook [Dept. of Radiology, and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Song, Ki Jun [Dept. of Biostatistics and Medical Informatics, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2016-06-15

    Clinical prediction models are developed to calculate estimates of the probability of the presence/occurrence or future course of a particular prognostic or diagnostic outcome from multiple clinical or non-clinical parameters. Radiologic imaging techniques are being developed for accurate detection and early diagnosis of disease, which will eventually affect patient outcomes. Hence, results obtained by radiological means, especially diagnostic imaging, are frequently incorporated into a clinical prediction model as important predictive parameters, and the performance of the prediction model may improve in both diagnostic and prognostic settings. This article explains in a conceptual manner the overall process of developing and validating a clinical prediction model involving radiological parameters in relation to the study design and statistical methods. Collection of a raw dataset; selection of an appropriate statistical model; predictor selection; evaluation of model performance using a calibration plot, Hosmer-Lemeshow test and c-index; internal and external validation; comparison of different models using c-index, net reclassification improvement, and integrated discrimination improvement; and a method to create an easy-to-use prediction score system will be addressed. This article may serve as a practical methodological reference for clinical researchers.

  2. A Comparative Experimental Design and Performance Analysis of Snort-Based Intrusion Detection System in Practical Computer Networks

    Directory of Open Access Journals (Sweden)

    Imdadul Karim

    2017-02-01

    Full Text Available As one of the most reliable technologies, network intrusion detection system (NIDS allows the monitoring of incoming and outgoing traffic to identify unauthorised usage and mishandling of attackers in computer network systems. To this extent, this paper investigates the experimental performance of Snort-based NIDS (S-NIDS in a practical network with the latest technology in various network scenarios including high data speed and/or heavy traffic and/or large packet size. An effective testbed is designed based on Snort using different muti-core processors, e.g., i5 and i7, with different operating systems, e.g., Windows 7, Windows Server and Linux. Furthermore, considering an enterprise network consisting of multiple virtual local area networks (VLANs, a centralised parallel S-NIDS (CPS-NIDS is proposed with the support of a centralised database server to deal with high data speed and heavy traffic. Experimental evaluation is carried out for each network configuration to evaluate the performance of the S-NIDS in different network scenarios as well as validating the effectiveness of the proposed CPS-NIDS. In particular, by analysing packet analysis efficiency, an improved performance of up to 10% is shown to be achieved with Linux over other operating systems, while up to 8% of improved performance can be achieved with i7 over i5 processors.

  3. A comparative analysis for multiattribute selection among renewable energy alternatives using fuzzy axiomatic design and fuzzy analytic hierarchy process

    Energy Technology Data Exchange (ETDEWEB)

    Kahraman, Cengiz; Kaya, Ihsan; Cebi, Selcuk [Istanbul Technical University, Department of Industrial Engineering, 34367, Macka-Istanbul (Turkey)

    2009-10-15

    Renewable energy is the energy generated from natural resources such as sunlight, wind, rain, tides and geothermal heat which are renewable. Energy resources are very important in perspective of economics and politics for all countries. Hence, the selection of the best alternative for any country takes an important role for energy investments. Among decision-making methodologies, axiomatic design (AD) and analytic hierarchy process (AHP) are often used in the literature. The fuzzy set theory is a powerful tool to treat the uncertainty in case of incomplete or vague information. In this paper, fuzzy multicriteria decision- making methodologies are suggested for the selection among renewable energy alternatives. The first methodology is based on the AHP which allows the evaluation scores from experts to be linguistic expressions, crisp, or fuzzy numbers, while the second is based on AD principles under fuzziness which evaluates the alternatives under objective or subjective criteria with respect to the functional requirements obtained from experts. The originality of the paper comes from the fuzzy AD application to the selection of the best renewable energy alternative and the comparison with fuzzy AHP. In the application of the proposed methodologies the most appropriate renewable energy alternative is determined for Turkey. (author)

  4. Torsional resistance as a principal component of the structural design of long bones: comparative multivariate evidence in birds.

    Science.gov (United States)

    de Margerie, Emmanuel; Sanchez, Sophie; Cubo, Jorge; Castanet, Jacques

    2005-01-01

    Here we study the occurrence of torsion-resisting morphological and histological features (thin bone walls, circular shaft cross-section, oblique collagen fibers, and laminar tissue arrangement) in a sample of 168 long bones from wings and legs of 22 bird species. These structural parameters were measured in mid diaphyseal undemineralized cross-sections and analyzed using uni-, bi-, and multivariate (principal components analysis) data analysis techniques. We found that the four variables are significantly and positively correlated, and that covariation between variables accounts for as much as 58% of the total variation. These results suggest that torsion is a main determinant of the macro- and microstructural design of long bones in birds. Humerus, ulna, and femur generally possess torsion-resisting features, while other bones (radius, carpometacarpus, tibiotarsus, tarsometatarsus, and foot phalanx) rather show bending/axial load-resisting structural properties. These results are congruent with in vivo strain data from the literature, which reported high torsional loading in humerus and ulna during flapping flight, but also in the subhorizontal avian femur during terrestrial locomotion. The precise function of the laminar tissue spatial arrangement, the role of pneumatization, and the influence of flight mode are discussed.

  5. Reproducibility of mandibular third molar assessment comparing two cone beam CT units in a matched pairs design.

    Science.gov (United States)

    Matzen, L H; Hintze, H; Spin-Neto, R; Wenzel, A

    2013-01-01

    The aim of this study was to evaluate the reproducibility of the third molar assessment, comparing five observers and two cone beam CT (CBCT) units. 28 patients, each with two impacted mandibular third molars, were included. Each patient was randomly examined with a Scanora(®) 3D (Soredex, Helsinki, Finland) CBCT unit in one mandibular third molar region and with a Cranex(®) 3D (Soredex) CBCT unit in the other region. Five observers with varying CBCT experience assessed all third molars and recorded the following variables: number and morphology of the roots, relation to the mandibular canal in two directions, shape of the canal and whether there was a direct contact between the roots of the molar and the mandibular canal. The radiographic assessments were compared pairwise among all observers for all variables. Wilcoxon's signed-rank test was used to test the differences in observer accordance percentages among the recorded variables in the images from the two units, and kappa statistics expressed interobserver reproducibility. The mean percentages for observer accordance ranged from 65.4 to 92.9 for Scanora 3D and 60.3 to 94.8 for Cranex 3D. There was no significant difference between the observer accordance in the two CBCT units (p > 0.05), except for assessing root flex in the mesiodistal direction, for which the observer accordance was higher for Scanora 3D (p third molar assessment. Observer variation existed, and experienced radiologists demonstrated the highest interobserver reproducibility for canal-related variables.

  6. Design and Fabrication of 3D printed Scaffolds with a Mechanical Strength Comparable to Cortical Bone to Repair Large Bone Defects.

    Science.gov (United States)

    Roohani-Esfahani, Seyed-Iman; Newman, Peter; Zreiqat, Hala

    2016-01-19

    A challenge in regenerating large bone defects under load is to create scaffolds with large and interconnected pores while providing a compressive strength comparable to cortical bone (100-150 MPa). Here we design a novel hexagonal architecture for a glass-ceramic scaffold to fabricate an anisotropic, highly porous three dimensional scaffolds with a compressive strength of 110 MPa. Scaffolds with hexagonal design demonstrated a high fatigue resistance (1,000,000 cycles at 1-10 MPa compressive cyclic load), failure reliability and flexural strength (30 MPa) compared with those for conventional architecture. The obtained strength is 150 times greater than values reported for polymeric and composite scaffolds and 5 times greater than reported values for ceramic and glass scaffolds at similar porosity. These scaffolds open avenues for treatment of load bearing bone defects in orthopaedic, dental and maxillofacial applications.

  7. Design and Fabrication of 3D printed Scaffolds with a Mechanical Strength Comparable to Cortical Bone to Repair Large Bone Defects

    Science.gov (United States)

    Roohani-Esfahani, Seyed-Iman; Newman, Peter; Zreiqat, Hala

    2016-01-01

    A challenge in regenerating large bone defects under load is to create scaffolds with large and interconnected pores while providing a compressive strength comparable to cortical bone (100–150 MPa). Here we design a novel hexagonal architecture for a glass-ceramic scaffold to fabricate an anisotropic, highly porous three dimensional scaffolds with a compressive strength of 110 MPa. Scaffolds with hexagonal design demonstrated a high fatigue resistance (1,000,000 cycles at 1–10 MPa compressive cyclic load), failure reliability and flexural strength (30 MPa) compared with those for conventional architecture. The obtained strength is 150 times greater than values reported for polymeric and composite scaffolds and 5 times greater than reported values for ceramic and glass scaffolds at similar porosity. These scaffolds open avenues for treatment of load bearing bone defects in orthopaedic, dental and maxillofacial applications.

  8. Effective use of modeling and simulation in designing bioequivalence and comparability studies of large-molecule compounds: the case of erythropoietin.

    Science.gov (United States)

    Nakai, Kiyohiko; Miyata, Kumiko; Iida, Satofumi; Kawanishi, Takehiko

    2015-06-01

    Bioequivalence and comparability studies are necessary for changing formulations of large-molecule drugs, such as antibody drugs and protein products, and in the development of their biosimilars. This study is the first application of modeling and simulation (M&S) in the design of bioequivalence and comparability studies of erythropoietin as an example of a large-molecule drug. A novel population pharmacokinetic and pharmacodynamic (PPK/PD) model was developed for erythropoietin. Based on this PPK/PD model, the probabilities of success of bioequivalence and comparability studies were simulated with various numbers of subjects and samples. The simulation indicated that the minimum numbers of subjects and samples required to satisfy the criteria for bioequivalence and comparability studies were as follows: fewest for the area under the serum concentration-time curve, more for the area under the efficacy-time curve, and most for the maximum serum concentration of erythropoietin. These results suggested that M&S could be successfully applied in the design of bioequivalence and comparability studies of large-molecule drugs.

  9. Effectiveness of behavioural graded activity compared with physiotherapy treatment in chronic neck pain: design of a randomised clinical trial [ISRCTN88733332

    OpenAIRE

    2004-01-01

    Abstract Background Chronic neck pain is a common complaint in the Netherlands with a point prevalence of 14.3%. Patients with chronic neck pain are often referred to a physiotherapist and, although many treatments are available, it remains unclear which type of treatment is to be preferred. The objective of this article is to present the design of a randomised clinical trial, Ephysion, which examines the clinical and cost effectiveness of behavioural graded activity compared with a physiothe...

  10. Solid lipid nanoparticles with and without hydroxypropyl-β-cyclodextrin: a comparative study of nanoparticles designed for colonic drug delivery

    Science.gov (United States)

    Spada, Gianpiera; Gavini, Elisabetta; Cossu, Massimo; Rassu, Giovanna; Giunchedi, Paolo

    2012-03-01

    New solid lipid nanoparticles (SLN), composed of Compritol ATO888 (C) and hydroxypropyl-β-cyclodextrin (HP), were developed in order to study a new colon-specific formulation for diclofenac sodium (D) delivery. The prepared batches differ from each other by the molecular ratio between HP and D and by the composition of the matrix. Nanoparticles composed of an exclusively lipid matrix and nanoparticles with an oligomeric and lipid matrix were compared in order to establish the effect of both components on the drug delivery tests performed. The SLN preparation method was based on the oil/water hot homogenization process. Emulsions produced were cooled at room temperature and lyophilized in order to obtain dried nanoparticles; possible damage to nanoparticle shape and size was avoided by the addition of cryoprotectants to the aqueous dispersion of nanoparticles before exsiccation. An in vitro toxicity study was performed using CaCo2 cells to establish the safety of the prepared SLN. Data obtained showed that production method studied guarantees emulsions composed of nanosized drops which can be dried by lyophilization into SLN with a size range of 300-600 nm. In vitro and ex vivo tests demonstrated that dried SLN can be considered as colon delivery systems; however, the matrix composition as well as the presence of cryoprotectant on their surface influences the release and permeation rate of D. The in vitro toxicity studies indicated that the SLN are well tolerated.

  11. Inlet and airframe compatibility for a V/STOL fighter/attack aircraft with top-mounted inlets

    Science.gov (United States)

    Durston, D. A.; Smeltzer, D. B.

    1982-01-01

    Aerodynamic force and inlet pressure data are obtained for 9.5% force and pressure models of a V/STOL fighter/attack aircraft configuration with top mounted twin inlets. Data are presented from tests conducted in the Ames Unitary Wind Tunnels at Mach numbers of 0.6, 0.9, and 1.2 at angles of attack up to 27 deg. and angles of sideslip up to 12 deg. Trimmed aerodynamic characteristics and inlet performance are compared for three different leading edge extension (LEX) configurations. The effects of wing leading and trailing-edge flaps on the inlet are also determined. Maneuver perfromance is calculated form combined force and inlet pressure data. The largest of the three LEX sizes tested gives the best airplane maneuver performance. Wing flap deflections improved inlet recovery at all Mach numbers.

  12. Synthesizing Equivalence Indices for the Comparative Evaluation of Technoeconomic Efficiency of Industrial Processes at the Design/Re-engineering Level

    Science.gov (United States)

    Fotilas, P.; Batzias, A. F.

    2007-12-01

    The equivalence indices synthesized for the comparative evaluation of technoeconomic efficiency of industrial processes are of critical importance since they serve as both, (i) positive/analytic descriptors of the physicochemical nature of the process and (ii) measures of effectiveness, especially helpful for investigated competitiveness in the industrial/energy/environmental sector of the economy. In the present work, a new algorithmic procedure has been developed, which initially standardizes a real industrial process, then analyzes it as a compromise of two ideal processes, and finally synthesizes the index that can represent/reconstruct the real process as a result of the trade-off between the two ideal processes taking as parental prototypes. The same procedure makes fuzzy multicriteria ranking within a set of pre-selected industrial processes for two reasons: (a) to analyze the process most representative of the production/treatment under consideration, (b) to use the `second best' alternative as a dialectic pole in absence of the two ideal processes mentioned above. An implantation of this procedure is presented, concerning a facility of biological wastewater treatment with six alternatives: activated sludge through (i) continuous-flow incompletely-stirred tank reactors in series, (ii) a plug flow reactor with dispersion, (iii) an oxidation ditch, and biological processing through (iv) a trickling filter, (v) rotating contactors, (vi) shallow ponds. The criteria used for fuzzy (to count for uncertainty) ranking are capital cost, operating cost, environmental friendliness, reliability, flexibility, extendibility. Two complementary indices were synthesized for the (ii)-alternative ranked first and their quantitative expressions were derived, covering a variety of kinetic models as well as recycle/bypass conditions. Finally, analysis of estimating the optimal values of these indices at maximum technoeconomic efficiency is presented and the implications

  13. Comparing attitudes about legal sanctions and teratogenic effects for cocaine, alcohol, tobacco and caffeine: A randomized, independent samples design

    Directory of Open Access Journals (Sweden)

    Alanis Kelly L

    2006-02-01

    than for the non-exposed teen beyond .0001 alpha level. The positive media program closed estimated grade point average differences and risks of later problems to a non-statistically significant margin, p >.05. Conclusion Ratings for prenatal cocaine were more negative than comparable ratings for alcohol, nicotine or caffeine exposure. Stereotypes can be reduced, showing viewers that positive postnatal environments ameliorate potential teratogenic effects of cocaine. Reducing negative stereotypes for crack babies may be a requisite for substantive changes in current policy.

  14. Airframe Noise Prediction of a Full Aircraft in Model and Full Scale Using a Lattice Boltzmann Approach

    Science.gov (United States)

    Fares, Ehab; Duda, Benjamin; Khorrami, Mehdi R.

    2016-01-01

    Unsteady flow computations are presented for a Gulfstream aircraft model in landing configuration, i.e., flap deflected 39deg and main landing gear deployed. The simulations employ the lattice Boltzmann solver PowerFLOW(Trademark) to simultaneously capture the flow physics and acoustics in the near field. Sound propagation to the far field is obtained using a Ffowcs Williams and Hawkings acoustic analogy approach. Two geometry representations of the same aircraft are analyzed: an 18% scale, high-fidelity, semi-span model at wind tunnel Reynolds number and a full-scale, full-span model at half-flight Reynolds number. Previously published and newly generated model-scale results are presented; all full-scale data are disclosed here for the first time. Reynolds number and geometrical fidelity effects are carefully examined to discern aerodynamic and aeroacoustic trends with a special focus on the scaling of surface pressure fluctuations and farfield noise. An additional study of the effects of geometrical detail on farfield noise is also documented. The present investigation reveals that, overall, the model-scale and full-scale aeroacoustic results compare rather well. Nevertheless, the study also highlights that finer geometrical details that are typically not captured at model scales can have a non-negligible contribution to the farfield noise signature.

  15. 具有带隙结构的迟滞比较器电路设计%Circuit Design of Hysteresis Comparator with Band-Gap Structure

    Institute of Scientific and Technical Information of China (English)

    徐静萍

    2011-01-01

    According to the requirement of low voltage and high stability, a circuit for the hysteresis comparator with band-gap structure is designed based on micropower consumption DC-DC converter drived by LED. Its minimum input voltage is 1. 2 V. Its core circuits consists of Band-gap comparator, emitter follower and hysteresis comparator. The bipolar technology is adopted in the circuit design. The circuit designed with the tecnology was simulated and verified with HSpice software.The results show that the hysteresis voltage of the hysteresis comparator is 8 mV, and the variation of the overturn threshold voltage with input voltage and temperature is small.%基于LED驱动的微功耗DC-DC转换器,针对低压高稳定性的要求设计了一款具有带隙结构的迟滞比较器电路,它的最低输入电压为1.2 V,其核心电路有带隙基准比较器、射极跟随器和迟滞比较器.整个电路采用Bipolar工艺设计,利用HSpice软件对所设计的电路进行了仿真与验证.结果表明,迟滞比较器的迟滞电压为8 mV.翻转门限电压随输入电压和温度的变化均很小.

  16. Design of the PROCON trial: a prospective, randomized multi – center study comparing cervical anterior discectomy without fusion, with fusion or with arthroplasty

    Directory of Open Access Journals (Sweden)

    Grotenhuis J André

    2006-11-01

    Full Text Available Abstract Background PROCON was designed to assess the clinical outcome, development of adjacent disc disease and costs of cervical anterior discectomy without fusion, with fusion using a stand alone cage and implantation of a Bryan's disc prosthesis. Description of rationale and design of PROCON trial and discussion of its strengths and limitations. Methods/Design Since proof justifying the use of implants or arthroplasty after cervical anterior discectomy is lacking, PROCON was designed. PROCON is a multicenter, randomized controlled trial comparing cervical anterior discectomy without fusion, with fusion with a stand alone cage or with implantation of a disc. The study population will be enrolled from patients with a single level cervical disc disease without myelopathic signs. Each treatment arm will need 90 patients. The patients will be followed for a minimum of five years, with visits scheduled at 6 weeks, 3 months, 12 months, and then yearly. At one year postoperatively, clinical outcome and self reported outcomes will be evaluated. At five years, the development of adjacent disc disease will be investigated. Discussion The results of this study will contribute to the discussion whether additional fusion or arthroplasty is needed and cost effective. Trial registration Current Controlled Trials ISRCTN41681847

  17. The Computer Aided Aircraft-design Package (CAAP)

    Science.gov (United States)

    Yalif, Guy U.

    1994-01-01

    The preliminary design of an aircraft is a complex, labor-intensive, and creative process. Since the 1970's, many computer programs have been written to help automate preliminary airplane design. Time and resource analyses have identified, 'a substantial decrease in project duration with the introduction of an automated design capability'. Proof-of-concept studies have been completed which establish 'a foundation for a computer-based airframe design capability', Unfortunately, today's design codes exist in many different languages on many, often expensive, hardware platforms. Through the use of a module-based system architecture, the Computer aided Aircraft-design Package (CAAP) will eventually bring together many of the most useful features of existing programs. Through the use of an expert system, it will add an additional feature that could be described as indispensable to entry level engineers and students: the incorporation of 'expert' knowledge into the automated design process.

  18. A Comparative Study of Electrolyte Flow and Slime Particle Transport in a Newly Designed Copper Electrolytic Cell and a Laboratory-Scale Conventional Electrolytic Cell

    Science.gov (United States)

    Zeng, Weizhi; Wang, Shijie; Free, Michael L.

    2016-08-01

    An innovative copper electrolytic cell was designed with its inlet at the cell top and its outlet near the cell bottom, in opposite to conventional electrolytic cells. It was modeled in COMSOL Multiphysics to simulate copper electrorefining process. Unlike conventional electrorefining cells, downward electrolyte flows are more dominant in the fluid flow field in this cell, which leads to faster settlement of slime particles and less contamination to the cathode. Copper concentration profiles, electrolyte flow velocity field, slime particle movements, and slime particle distributions were obtained as simulation results, which were compared with those in a laboratory-scale conventional electrolytic cell. Advantages of the newly designed electrolytic cell were found: copper ions are distributed more uniformly in the cell with a thinner diffusion layer near the cathode; stronger convection exists in the inter-electrode domain with dominant downward flows; and slime particles have larger possibilities to settle down and are less likely to reach the cathode.

  19. Designing parks. An examination of contemporary approaches to design in landscape architecture, based on a comparative design analysis of entries for the Concours International, Parc de la Vilette Paris, 1982-83.

    NARCIS (Netherlands)

    Baljon, L.

    1992-01-01

    PARK DESIGNS Parks are planted places in which vegetation, earth, water, and constructions are cultivated in such a way through composition that they acquire a meaning beyond the significance of the single plant. Without imagination a park is a mere dry décor for people who come and go; a meaningles

  20. Small Airframe Manufacturer's Icing Perspective

    Science.gov (United States)

    Hoppins, Jim

    2009-01-01

    This viewgraph presentation describes the icing effects, risk mitigation practices, and icing certifications for various Cessna small aircraft models. NASA's role in the development of simulation tools for icing certifications is also discussed.

  1. Flexible missile autopilot design studies with PC-MATLAB/386

    Science.gov (United States)

    Ruth, Michael J.

    1989-01-01

    Development of a responsive, high-bandwidth missile autopilot for airframes which have structural modes of unusually low frequency presents a challenging design task. Such systems are viable candidates for modern, state-space control design methods. The PC-MATLAB interactive software package provides an environment well-suited to the development of candidate linear control laws for flexible missile autopilots. The strengths of MATLAB include: (1) exceptionally high speed (MATLAB's version for 80386-based PC's offers benchmarks approaching minicomputer and mainframe performance); (2) ability to handle large design models of several hundred degrees of freedom, if necessary; and (3) broad extensibility through user-defined functions. To characterize MATLAB capabilities, a simplified design example is presented. This involves interactive definition of an observer-based state-space compensator for a flexible missile autopilot design task. MATLAB capabilities and limitations, in the context of this design task, are then summarized.

  2. Electrospinning/electrospraying vs. electrospinning: A comparative study on the design of poly(L-lactide)/zinc oxide non-woven textile

    Science.gov (United States)

    Virovska, Daniela; Paneva, Dilyana; Manolova, Nevena; Rashkov, Iliya; Karashanova, Daniela

    2014-08-01

    New hybrid fibrous materials from the biocompatible and biodegradable aliphatic polyester poly(L-lactide) (PLA) and pristine or surface-functionalized nanosized zinc oxide were prepared. The application of the techniques: (i) electrospinning of a suspension of ZnO in PLA solution, or (ii) simultaneous electrospinning of PLA solution and electrospraying of a ZnO suspension in PLA solution (at low PLA concentration) enabled the fabrication of hybrid materials of diverse design: non-woven textile consisting of fibers in which ZnO was deposited on the fibers' surface (designated as type "on") or was mainly in the fibers' bulk (designated as type "in"). The photocatalytic activity of the new fibrous materials was estimated in respect to Methylene Blue (MB) and Reactive Red (RR) dyes. Type "on" hybrid materials had higher photocatalytic activity as compared to type "in" materials. It was shown that type "on" materials preserved their photocatalytic activity in respect to MB even after three repeated uses, while for the RR dye the same held true for ZnO-on-PLA mats only. The type "on" materials exhibited antimicrobial activity against the pathogenic microorganism Staphylococcus aureus as evidenced by the performed microbiological tests.

  3. Comparative Study on Various Geometrical Core Design of 300 MWth Gas Cooled Fast Reactor with UN-PuN Fuel Longlife without Refuelling

    Science.gov (United States)

    Dewi Syarifah, Ratna; Su'ud, Zaki; Basar, Khairul; Irwanto, Dwi

    2017-07-01

    Nuclear power has progressive improvement in the operating performance of exiting reactors and ensuring economic competitiveness of nuclear electricity around the world. The GFR use gas coolant and fast neutron spectrum. This research use helium coolant which has low neutron moderation, chemical inert and single phase. Comparative study on various geometrical core design for modular GFR with UN-PuN fuel long life without refuelling has been done. The calculation use SRAC2006 code both PIJ calculation and CITATION calculation. The data libraries use JENDL 4.0. The variation of fuel fraction is 40% until 65%. In this research, we varied the geometry of core reactor to find the optimum geometry design. The variation of the geometry design is balance cylinder; it means that the diameter active core (D) same with height active core (H). Second, pancake cylinder (D>H) and third, tall cylinder (D

  4. Comparing three stochastic search algorithms for computational protein design: Monte Carlo, replica exchange Monte Carlo, and a multistart, steepest-descent heuristic.

    Science.gov (United States)

    Mignon, David; Simonson, Thomas

    2016-07-15

    Computational protein design depends on an energy function and an algorithm to search the sequence/conformation space. We compare three stochastic search algorithms: a heuristic, Monte Carlo (MC), and a Replica Exchange Monte Carlo method (REMC). The heuristic performs a steepest-descent minimization starting from thousands of random starting points. The methods are applied to nine test proteins from three structural families, with a fixed backbone structure, a molecular mechanics energy function, and with 1, 5, 10, 20, 30, or all amino acids allowed to mutate. Results are compared to an exact, "Cost Function Network" method that identifies the global minimum energy conformation (GMEC) in favorable cases. The designed sequences accurately reproduce experimental sequences in the hydrophobic core. The heuristic and REMC agree closely and reproduce the GMEC when it is known, with a few exceptions. Plain MC performs well for most cases, occasionally departing from the GMEC by 3-4 kcal/mol. With REMC, the diversity of the sequences sampled agrees with exact enumeration where the latter is possible: up to 2 kcal/mol above the GMEC. Beyond, room temperature replicas sample sequences up to 10 kcal/mol above the GMEC, providing thermal averages and a solution to the inverse protein folding problem. © 2016 Wiley Periodicals, Inc.

  5. Computer-designed surgical guide template compared with free-hand operation for mesiodens extraction in premaxilla using “trapdoor” method

    Science.gov (United States)

    Hu, Ying Kai; Xie, Qian Yang; Yang, Chi; Xu, Guang Zhou

    2017-01-01

    Abstract The aim of this study was to introduce a novel method of mesiodens extraction using a vascularized pedicled bone flap by piezosurgery and to compare the differences between a computer-aided design surgical guide template and free-hand operation. A total of 8 patients with mesiodens, 4 with a surgical guide (group I), and 4 without it (group II) were included in the study. The surgical design was to construct a trapdoor pedicle on the superior mucoperiosteal attachment with application of piezosurgery. The bone lid was repositioned after mesiodens extraction. Group I patients underwent surgeries based on the preoperative planning with surgical guide templates, while group II patients underwent free-hand operation. The outcome variables were success rate, intraoperative time, anterior nasal spine (ANS) position, changes of nasolabial angle (NLA), and major complications. Data from the 2 groups were compared by SPSS 17.0, using Wilcoxon test. The operative time was significantly shorter in group I patients. All the mesiodentes were extracted successfully and no obvious differences of preoperative and postoperative ANS position and NLA value were found in both groups. The patients were all recovered uneventfully. Surgical guide templates can enhance clinical accuracy and reduce operative time by facilitating accurate osteotomies. PMID:28658139

  6. Effectiveness of computer-navigated minimally invasive total hip surgery compared to conventional total hip arthroplasty: design of a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Bulstra Sjoerd K

    2007-01-01

    Full Text Available Abstract Background Moderate to severe osteoarthrosis is the most common indication for Total Hip Arthroplasty (THA. Minimally Invasive Total Hip Surgery (MIS and computer-navigated surgery were introduced several years ago. However, the literature lacks well-designed studies that provide evidence of superiority of computer-navigated MIS over a conventional THA technique. Hence, the purpose of this study is to compare (costeffectiveness of computer-navigated MIS with a conventional technique for THA. It is our hypothesis that computer-navigated MIS will lead to a quicker recovery during the early postoperative period (3 months, and to an outcome at least as good 6 months postoperatively. We also hypothesize that computer-navigated MIS leads to fewer perioperative complications and better prosthesis positioning. Furthermore, cost advantages of computer-navigated MIS over conventional THA technique are expected. Methods/design A cluster randomized controlled trial will be executed. Patients between the ages of 18 and 75 admitted for primary cementless unilateral THA will be included. Patients will be stratified using the Charnley classification. They will be randomly allocated to have computer-navigated MIS or conventional THA technique. Measurements take place preoperatively, perioperatively, and 6 weeks and 3 and 6 months postoperatively. Degree of limping (gait analysis, self-reported functional status and health-related quality of life (questionnaires will be assessed preoperatively as well as postoperatively. Perioperative complications will be registered. Radiographic evaluation of prosthesis positioning will take place 6 weeks postoperatively. An evaluation of costs within and outside the healthcare sector will focus on differences in costs between computer-navigated MIS and conventional THA technique. Discussion Based on studies performed so far, few objective data quantifying the risks and benefits of computer-navigated MIS are available

  7. Comparing two methods of education (virtual versus traditional) on learning of Iranian dental students: a post-test only design study.

    Science.gov (United States)

    Moazami, Fariborz; Bahrampour, Ehsan; Azar, Mohammad Reza; Jahedi, Farzad; Moattari, Marzieh

    2014-03-05

    The importance of using technologies such as e-learning in different disciplines is discussed in the literature. Researchers have measured the effectiveness of e-learning in a number of fields.Considering the lack of research on the effectiveness of online learning in dental education particularly in Iran, the advantages of these learning methods and the positive university atmosphere regarding the use of online learning. This study, therefore, aims to compare the effects of two methods of teaching (virtual versus traditional) on student learning. This post-test only design study approached 40, fifth year dental students of Shiraz University of Medical Sciences. From this group, 35 students agreed to participate. These students were randomly allocated into two groups, experimental (virtual learning) and comparison (traditional learning). To ensure similarity between groups, we compared GPAs of all participants by the Mann-Whitney U test (P > 0.05). The experimental group received a virtual learning environment courseware package specifically designed for this study, whereas the control group received the same module structured in a traditional lecture form. The virtual learning environment consisted of online and offline materials. Two identical valid, reliable post-tests that consisted of 40 multiple choice questions (MCQs) and 4 essay questions were administered immediately (15 min) after the last session and two months later to assess for knowledge retention. Data were analyzed by SPSS version 20. A comparison of the mean knowledge score of both groups showed that virtual learning was more effective than traditional learning (effect size = 0.69). The newly designed virtual learning package is feasible and will result in more effective learning in comparison with lecture-based training. However further studies are needed to generalize the findings of this study.

  8. A comparative study between China and U.S. on seismic design philosophy and practice of a long span arch bridge

    Institute of Scientific and Technical Information of China (English)

    Xu Yan; George C Lee; Fan Lichu; Hu Shide

    2006-01-01

    This paper presents the first of a series of case studies on the seismic design of long span bridges (cablestayed bridges, suspension bridges and arch bridges) under a cooperative research project on seismic behavior and design of highway bridges between the State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University and the Multidisciplinary Center for Earthquake Engineering Research, University at Buffalo. The objective of this series of case studies is to examine the differences and similarities on the seismic design practice of long span bridges in China and the U.S., to identify research needs and to develop design guidelines beneficial to bridge engineers in both countries. Unlike short to medium span bridges, long span bridges are not included in most seismic design specifications, mainly because they are location dependent and structurally unique. In this paper, an available model of a steel tied half through arch bridge with a main span of 550m in China is discussed. Analysis is focused on comparisons of the seismic responses due to different ground motions. Seismic design criteria and seismic performance requirements for long span bridges in both countries were first introduced and compared, and then three near field earthquake records with large vertical components were selected as the excitations to examine the seismic behavior and seismic vulnerability of the bridge. Results show that (1) the selected near field ground motions cause larger responses to key components (critical sections) of the bridge (such as arch rib ends) with a maximum increase of more than twice those caused by the site specific ground motions; (2) piers, longitudinal girders and arch crowns are more vulnerable to vertical motions, especially their axial forces; and (3) large vertical components of near field ground motions may not significantly affect the bridge's internal forces provided that their peak acceleration spectra ordinates only appear at periods

  9. Comparative efficacy of the Cognitive Behavioral Analysis System of Psychotherapy versus Supportive Psychotherapy for early onset chronic depression: design and rationale of a multisite randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Berger Mathias

    2011-08-01

    Full Text Available Abstract Background Effective treatment strategies for chronic depression are urgently needed since it is not only a common and particularly disabling disorder, but is also considered treatment resistant by most clinicians. There are only a few studies on chronic depression indicating that traditional psycho- and pharmacological interventions are not as effective as in acute, episodic depression. Current medications are no more effective than those introduced 50 years ago whereas the only psychotherapy developed specifically for the subgroup of chronic depression, the Cognitive Behavioral Analysis System of Psychotherapy (CBASP, faired well in one large trial. However, CBASP has never been directly compared to a non-specific control treatment. Methods/Design The present article describes the study protocol of a multisite parallel-group randomized controlled trial in Germany. The purpose of the study is to estimate the efficacy of CBASP compared to supportive psychotherapy in 268 non-medicated early-onset chronically depressed outpatients. The intervention includes 20 weeks of acute treatment with 24 individual sessions followed by 28 weeks of continuation treatment with another 8 sessions. Depressive symptoms are evaluated 20 weeks after randomisation by means of the 24-item Hamilton Rating Scale of Depression (HRSD. Secondary endpoints are depressive symptoms after 12 and 48 weeks, and remission after 12, 20, and 48 weeks. Primary outcome will be analysed using analysis of covariance (ANCOVA controlled for pre-treatment scores and site. Analyses of continuous secondary variables will be performed using linear mixed models. For remission rates, chi-squared tests and logistic regression will be applied. Discussion The study evaluates the comparative effects of a disorder-specific psychotherapy and a well designed non-specific psychological approach in the acute and continuation treatment phase in a large sample of early-onset chronically

  10. Taguchi Experimental Design for Optimization of Recombinant Human Growth Hormone Production in CHO Cell Lines and Comparing its Biological Activity with Prokaryotic Growth Hormone.

    Science.gov (United States)

    Aghili, Zahra Sadat; Zarkesh-Esfahani, Sayyed Hamid

    2017-09-12

    Growth hormone deficiency results in growth retardation in children and the GH deficiency syndrome in adults and they need to receive recombinant-GH in order to rectify the GH deficiency symptoms. Mammalian cells have become the favorite system for production of recombinant proteins for clinical application compared to prokaryotic systems because of their capability for appropriate protein folding, assembly, post-translational modification and proper signal. However, production level in mammalian cells is generally low compared to prokaryotic hosts. Taguchi has established orthogonal arrays to describe a large number of experimental situations mainly to reduce experimental errors and to enhance the efficiency and reproducibility of laboratory experiments.In the present study, rhGH was produced in CHO cells and production of rhGH was assessed using Dot blotting, western blotting and Elisa assay. For optimization of rhGH production in CHO cells using Taguchi method An M16 orthogonal experimental design was used to investigate four different culture components. The biological activity of rhGH was assessed using LHRE-TK-Luciferase reporter gene system in HEK-293 and compared to the biological activity of prokaryotic rhGH.A maximal productivity of rhGH was reached in the conditions of 1%DMSO, 1%glycerol, 25 µM ZnSO4 and 0 mM NaBu. Our findings indicate that control of culture conditions such as the addition of chemical components helps to develop an efficient large-scale and industrial process for the production of rhGH in CHO cells. Results of bioassay indicated that rhGH produced by CHO cells is able to induce GH-mediated intracellular cell signaling and showed higher bioactivity when compared to prokaryotic GH at the same concentrations. © Georg Thieme Verlag KG Stuttgart · New York.

  11. Design of COSMIC: a randomized, multi-centre controlled trial comparing conservative or early surgical management of incomplete cervical cord syndrome without spinal instability

    Directory of Open Access Journals (Sweden)

    Bartels Ronald HMA

    2013-01-01

    Full Text Available Abstract Background Incomplete cervical cord syndrome without spinal instability is a very devastating event for the patient and the family. It is estimated that up to 25% of all traumatic spinal cord lesions belong to this category. The treatment for this type of spinal cord lesion is still subject of discussion. From a biological point of view early surgery could prevent secondary damage due to ongoing compression of the already damaged spinal cord. Historically, however, conservative treatment was propagated with good clinical results. Proponents for early surgery as well those favoring conservative treatment are still in debate. The proposed trial will contribute to the discussion and hopefully also to a decrease in the variability of clinical practice. Methods/Design A randomized controlled trial is designed to compare the clinical outcome of early surgical strategy versus a conservative approach. The primary outcome is clinical outcome according to mJOA. This also measured by ASIA score, DASH score and SCIM III score. Other endpoints are duration of the stay at a high care department (medium care, intensive care, duration of the stay at the hospital, complication rate, mortality rate, sort of rehabilitation, and quality of life. A sample size of 36 patients per group was calculated to reach a power of 95%. The data will be analyzed as intention-to-treat at regular intervals, but the end evaluation will take place at two years post-injury. Discussion At the end of the study, clinical outcomes between treatments attitudes can be compared. Efficacy, but also efficiency can be determined. A goal of the study is to determine which treatment will result in the best quality of life for the patients. This study will certainly contribute to more uniformity of treatment offered to patients with a special sort of spinal cord injury. Trial Registration Gov: NCT01367405

  12. Testing the comparative effects of physical activity advice by humans vs. computers in underserved populations: The COMPASS trial design, methods, and baseline characteristics.

    Science.gov (United States)

    King, Abby C; Campero, Ines; Sheats, Jylana L; Castro Sweet, Cynthia M; Garcia, Dulce; Chazaro, Aldo; Blanco, German; Hauser, Michelle; Fierros, Fernando; Ahn, David K; Diaz, Jose; Done, Monica; Fernandez, Juan; Bickmore, Timothy

    2017-10-01

    While physical inactivity is a key risk factor for a range of chronic diseases and conditions associated with aging, a significant proportion of midlife and older adults remain insufficiently active. This is particularly true for ethnic minority populations such as Latino adults for whom few culturally adapted programs have been developed and tested. The major objective of this 12-month cluster-randomized controlled trial is to test the comparative effectiveness of two linguistically and culturally adapted, community-based physical activity interventions with the potential for broad reach and translation. Ten local community centers serving a sizable number of Latino residents were randomized to receive one of two physical activity interventions. The Virtual Advisor program employs a computer-based embodied conversational agent named "Carmen" to deliver interactive, individually tailored physical activity advice and support. A similar intervention program is delivered by trained Peer Advisors. The target population consists of generally healthy, insufficiently active Latino adults ages 50years and older living within proximity to a designated community center. The major outcomes are changes in walking and other forms of physical activity measured via self-report and accelerometry. Secondary outcomes include physical function and well-being variables. In addition to these outcome analyses, comparative cost analysis of the two programs, potential mediators of intervention success, and baseline moderators of intervention effects will be explored to better determine which subgroups do best with which type of intervention. Here we present the study design and methods, including recruitment strategies and yield as well as study baseline characteristics. clinicaltrial.gov Identifier=NCT02111213. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. A replicate designed bioequivalence study to compare two fixed-dose combination products of artesunate and amodiaquine in healthy chinese volunteers.

    Science.gov (United States)

    Liu, Yun; Hu, Chaoying; Liu, Gangyi; Jia, Jingying; Yu, Chen; Zhu, Jianmin; Zheng, Qingsi; Zhang, Kanyin E

    2014-10-01

    Artesun-Plus is a fixed-dose combination antimalarial agent containing artesunate and amodiaquine. The current study was conducted to compare the pharmacokinetic and safety profiles of Artesun-Plus and the WHO-designated comparator product Artesunate Amodiaquine Winthrop. To overcome the high intrasubject variability of artesunate, the study applied a two-sequence and four-period crossover (2 by 4), replicate study design to assess bioequivalence between the two products in 31 healthy male Chinese volunteers under fasting conditions. The results showed that the values of the geometric mean ratios of maximum concentration of drug in plasma (Cmax) and area under the concentration-time curve from time zero to the last blood sample collection (AUC0-last) for the artesunate component in the test and reference products were 95.9% and 93.9%, respectively, and that the corresponding 90% confidence intervals were 84.5% to 108.7% and 87.2% to 101.1%, while the geometric mean ratios for the amodiaquine component in the test and reference products were 95.0% and 100.0%, respectively, and the corresponding 90% confidence intervals were 86.7% to 104.1% and 93.5% to 107.0%. In conclusion, bioequivalence between the two artesunate and amodiaquine fixed-dose combination products was demonstrated for both components. The study also confirmed high intrasubject variability, especially for artesunate: the coefficients of variation (CV) of Cmax values for the test and reference products were 39.2% and 43.7%, respectively, while those for amodiaquine were 30.6% and 30.2%, respectively.

  14. Dutch randomized trial comparing standard catheter-directed thrombolysis versus Ultrasound-accElerated Thrombolysis for thromboembolic infrainguinal disease (DUET: design and rationale

    Directory of Open Access Journals (Sweden)

    Fioole Bram

    2011-01-01

    Full Text Available Abstract Background The use of thrombolytic therapy in the treatment of thrombosed infrainguinal native arteries and bypass grafts has increased over the years. Main limitation of this treatment modality, however, is the occurrence of bleeding complications. Low intensity ultrasound (US has been shown to accelerate enzymatic thrombolysis, thereby reducing therapy time. So far, no randomized trials have investigated the application of US-accelerated thrombolysis in the treatment of thrombosed infra-inguinal native arteries or bypass grafts. The DUET study (Dutch randomized trial comparing standard catheter-directed thrombolysis versus Ultrasound-accElerated Thrombolysis for thrombo-embolic infrainguinal disease is designed to assess whether US-accelerated thrombolysis will reduce therapy time significantly compared with standard catheter-directed thrombolysis. Methods/design Sixty adult patients with recently (between 1 and 7 weeks thrombosed infrainguinal native arteries or bypass grafts with acute limb ischemia class I or IIa, according to the Rutherford classification for acute ischemia, will be randomly allocated to either standard thrombolysis (group A or US-accelerated thrombolysis (group B. Patients will be recruited from 5 teaching hospitals in the Netherlands during a 2-year period. The primary endpoint is the duration of catheter-directed thrombolysis needed for uninterrupted flow in the thrombosed infrainguinal native artery or bypass graft, with outflow through at least 1 crural artery. Discussion The DUET study is a randomized controlled trial that will provide evidence of whether US-accelerated thrombolysis will significantly reduce therapy time in patients with recently thrombosed infrainguinal native arteries or bypass grafts, without an increase in complications. Trial registration Current Controlled Trials ISRCTN72676102

  15. Pancreatitis, very early compared with normal start of enteral feeding (PYTHON trial: design and rationale of a randomised controlled multicenter trial

    Directory of Open Access Journals (Sweden)

    Schaapherder Alexander F

    2011-03-01

    Full Text Available Abstract Background In predicted severe acute pancreatitis, infections have a negative effect on clinical outcome. A start of enteral nutrition (EN within 24 hours of onset may reduce the number of infections as compared to the current practice of starting an oral diet and EN if necessary at 3-4 days after admission. Methods/Design The PYTHON trial is a randomised controlled, parallel-group, superiority multicenter trial. Patients with predicted severe acute pancreatitis (Imrie-score ≥ 3 or APACHE-II score ≥ 8 or CRP > 150 mg/L will be randomised to EN within 24 hours or an oral diet and EN if necessary, after 72 hours after hospital admission. During a 3-year period, 208 patients will be enrolled from 20 hospitals of the Dutch Pancreatitis Study Group. The primary endpoint is a composite of mortality or infections (bacteraemia, infected pancreatic or peripancreatic necrosis, pneumonia during hospital stay or within 6 months following randomisation. Secondary endpoints include other major morbidity (e.g. new onset organ failure, need for intervention, intolerance of enteral feeding and total costs from a societal perspective. Discussion The PYTHON trial is designed to show that a very early ( Trial Registration ISRCTN: ISRCTN18170985

  16. Thailand Ranks Second in the World for Number of Road Accidents under Thailand’s Codes of Geometrical Design and Traffic Engineering Concept When Compared with AASHTO

    Directory of Open Access Journals (Sweden)

    Cheewapattananuwong Weeradej

    2016-01-01

    Full Text Available Traffic problems in Bangkok have an influence on road users during peak hours. Especially, the traffic bottleneck on curves under the saturation flow situation must be remedied in order to increase the roadway capacity and speed. However, the appropriate speed for heavy vehicles is taken into consideration during off peak after the increasing lanes. This leads to the Rollover of heavy truck and rear-end collisions which are the main causes of vehicles accidents on curves. In addition, road accidents on curves account for the majority of all accidents in Thailand. According to the road accidents data collected in Thailand, 44 road deaths per 100,000 people, the country ranks second in the world for road accidents. When Thailand’s Code of Geometrical Design is compared with AASHTO (The American Association of State Highway and Transportation Officials, the super elevation length of Thailand’s Code is more than AASHTO. As a result, drivers are not made aware of the appropriate speed and the stooping sight distances (SSD on curves. Therefore, the Design of Traffic Signage under the Perception and Reaction Times (PRT for Thai Drivers will be taken into account.

  17. Conceptual Design of an APT Reusable Spaceplane

    Science.gov (United States)

    Corpino, S.; Viola, N.

    This paper concerns the conceptual design of an Aerial Propellant Transfer reusable spaceplane carried out during our PhD course under the supervision of prof. Chiesa. The new conceptual design methodology employed in order to develop the APT concept and the main characteristics of the spaceplane itself will be presented and discussed. The methodology for conceptual design has been worked out during the last three years. It was originally thought for atmospheric vehicle design but, thanks to its modular structure which makes it very flexible, it has been possible to convert it to space transportation systems design by adding and/or modifying a few modules. One of the major improvements has been for example the conception and development of the mission simulation and trajectory optimisation module. The methodology includes as main characteristics and innovations the latest techniques of geometric modelling and logistic, operational and cost aspects since the first stages of the project. Computer aided design techniques are used to obtain a better definition of the product at the end of the conceptual design phase and virtual reality concepts are employed to visualise three-dimensional installation and operational aspects, at least in part replacing full-scale mock- ups. The introduction of parametric three-dimensional CAD software integrated into the conceptual design methodology represents a great improvement because it allows to carry out different layouts and to assess them immediately. It is also possible to link the CAD system to a digital prototyping software which combines 3D visualisation and assembly analysis, useful to define the so-called Digital Mock-Up at Conceptual Level (DMUCL) which studies the integration between the on board systems, sized with simulation algorithms, and the airframe. DMUCL represents a very good means to integrate the conceptual design with a methodology turned towards dealing with Reliability, Availability, Maintainability and

  18. The effects of nocturnal hemodialysis compared to conventional hemodialysis on change in left ventricular mass: Rationale and study design of a randomized controlled pilot study

    Directory of Open Access Journals (Sweden)

    Klarenbach Scott

    2006-02-01

    Full Text Available Abstract Background Nocturnal hemodialysis (NHD is an alternative to conventional three times per week hemodialysis (CvHD and has been reported to improve several health outcomes. To date, no randomized controlled trial (RCT has compared NHD and CvHD. We have undertaken a multi-center RCT in hemodialysis patients comparing the effect of NHD to CvHD on left ventricular (LV mass, as measured by cardiac magnetic resonance imaging (cMR. Methodology/design All patients in Alberta, Canada, expressing an interest in performing NHD are eligible for the study. Patients enrolled in the study will be randomized to either NHD or CvHD for a six month period. All patients will have a full clinical assessment, including collection of biochemical and cMR data at baseline and at 6 months. Both groups of patients will be monitored biweekly to optimize blood pressure (BP to a goal of Discussion To our knowledge, this study will be the first RCT evaluating health outcomes in NHD. The impact of NHD on LV mass represents a clinically important outcome which will further elucidate the potential benefits of NHD and guide future clinical endpoint studies.

  19. Effectiveness of behavioural graded activity compared with physiotherapy treatment in chronic neck pain: design of a randomised clinical trial [ISRCTN88733332

    Directory of Open Access Journals (Sweden)

    Vos Cees J

    2004-10-01

    Full Text Available Abstract Background Chronic neck pain is a common complaint in the Netherlands with a point prevalence of 14.3%. Patients with chronic neck pain are often referred to a physiotherapist and, although many treatments are available, it remains unclear which type of treatment is to be preferred. The objective of this article is to present the design of a randomised clinical trial, Ephysion, which examines the clinical and cost effectiveness of behavioural graded activity compared with a physiotherapy treatment for patients with chronic non-specific neck pain. Methods Eligible patients with non-specific neck pain persisting longer than 3 months will be randomly allocated to either the behavioural graded activity programme or to the physiotherapy treatment. The graded activity programme is based on an operant approach, which uses a time-contingent method to increase the patient's activity level. This treatment is compared with physiotherapy treatment using a pain-contingent method. Primary treatment outcome is the patient's global perceived effect concerning recovery from the complaint. Global perceived effect on daily functioning is also explored as primary outcome to establish the impact of treatment on daily activity. Direct and indirect costs will also be assessed. Secondary outcomes include the patient's main complaints, pain intensity, medical consumption, functional status, quality of life, and psychological variables. Recruitment of patients will take place up to the end of the year 2004 and follow-up measurement will continue until end 2005.

  20. Review of the Most Important Design Optimization Technique of Composite Wing

    Directory of Open Access Journals (Sweden)

    Bogdan-Alexandru BELEGA

    2016-12-01

    Full Text Available The scope of wing optimization is to design a structure that meets all the airworthiness demands while minimizing its weight. This paper introduces a review for the most important optimization design tools of composite wings with multiple load cases and large scale design variables. Each discipline resorts to accurate design to ensure better performance. Accurate design and multidisciplinary optimization design for wings need large scale design variables. The structural design of an airframe is determined by multidisciplinary criteria (stress, fatigue, buckling, control surface effectiveness, flutter and weight etc.. Several thousands of structural sizes of stringers, panels, ribs etc. have to be determined considering hundreds of thousands of requirements to find an optimum solution, i.e. a design fulfilling all requirements with a minimum weight or minimum cost respectively.

  1. Comparative efficacy of the Cognitive Behavioral Analysis System of Psychotherapy versus supportive psychotherapy for early onset chronic depression: design and rationale of a multisite randomized controlled trial.

    Science.gov (United States)

    Schramm, Elisabeth; Hautzinger, Martin; Zobel, Ingo; Kriston, Levente; Berger, Mathias; Härter, Martin

    2011-08-17

    Effective treatment strategies for chronic depression are urgently needed since it is not only a common and particularly disabling disorder, but is also considered treatment resistant by most clinicians. There are only a few studies on chronic depression indicating that traditional psycho- and pharmacological interventions are not as effective as in acute, episodic depression. Current medications are no more effective than those introduced 50 years ago whereas the only psychotherapy developed specifically for the subgroup of chronic depression, the Cognitive Behavioral Analysis System of Psychotherapy (CBASP), faired well in one large trial. However, CBASP has never been directly compared to a non-specific control treatment. The present article describes the study protocol of a multisite parallel-group randomized controlled trial in Germany. The purpose of the study is to estimate the efficacy of CBASP compared to supportive psychotherapy in 268 non-medicated early-onset chronically depressed outpatients. The intervention includes 20 weeks of acute treatment with 24 individual sessions followed by 28 weeks of continuation treatment with another 8 sessions. Depressive symptoms are evaluated 20 weeks after randomisation by means of the 24-item Hamilton Rating Scale of Depression (HRSD). Secondary endpoints are depressive symptoms after 12 and 48 weeks, and remission after 12, 20, and 48 weeks. Primary outcome will be analysed using analysis of covariance (ANCOVA) controlled for pre-treatment scores and site. Analyses of continuous secondary variables will be performed using linear mixed models. For remission rates, chi-squared tests and logistic regression will be applied. The study evaluates the comparative effects of a disorder-specific psychotherapy and a well designed non-specific psychological approach in the acute and continuation treatment phase in a large sample of early-onset chronically depressed patients. ClinicalTrials.gov (NCT00970437).

  2. CHoosing Options for Insomnia in Cancer Effectively (CHOICE): Design of a patient centered comparative effectiveness trial of acupuncture and cognitive behavior therapy for insomnia.

    Science.gov (United States)

    Garland, Sheila N; Gehrman, Philip; Barg, Frances K; Xie, Sharon X; Mao, Jun J

    2016-03-01

    Insomnia is a prevalent and persistent side effect of cancer, which if left unaddressed, can be unremitting and negatively influence physical and mental well-being. Acupuncture and Cognitive Behavioral Therapy (CBT) are commonly used non-pharmacological treatments that are efficacious for treating insomnia in cancer patients; however, little is known about the comparative effectiveness of these options. The goal of personalized medicine is to determine which treatments are most effective for which individuals, and patient preference for treatment is a particularly important contributor to adherence and outcomes. Here we describe the design of a clinical trial that begins to determine how best to personalize the treatment of insomnia for cancer survivors. This project is a randomized controlled comparative effectiveness trial with a nested qualitative study comparing acupuncture and CBT for insomnia and co-morbid symptoms in a heterogeneous sample of 160 cancer survivors. The primary aim is to determine which treatment is associated with the largest reduction in insomnia severity. The secondary aim is to examine the demographic, clinical, and psychological characteristics that predict and/or moderate treatment effect. Patients will receive ten treatments of acupuncture or 7 sessions of CBT over eight weeks and complete validated patient-reported outcome measures of sleep and co-morbid symptoms at baseline, mid-treatment, post-treatment, and at three-months to assess durability of effect. The results of the proposed study have the potential to improve healthcare outcomes by helping cancer survivors and their caregivers make informed and evidence-based decisions, leading to patient-centered and personalized care for cancer survivors with insomnia.

  3. Effectiveness of manual therapy compared to usual care by the general practitioner for chronic tension-type headache: design of a randomised clinical trial

    Directory of Open Access Journals (Sweden)

    Dekker Joost

    2009-02-01

    Full Text Available Abstract Background Patients with Chronic Tension Type Headache (CTTH report functional and emotional impairments (loss of workdays, sleep disturbances, emotional well-being and are at risk for overuse of medication. Manual therapy may improve symptoms through mobilisation of the spine, correction of posture, and training of cervical muscles. We present the design of a randomised clinical trial (RCT evaluating the effectiveness of manual therapy (MT compared to usual care by the general practitioner (GP in patients with CTTH. Methods and design Patients are eligible for participation if they present in general practice with CTTH according to the classification of the International Headache Society (IHS. Participants are randomised to either usual GP care according to the national Dutch general practice guidelines for headache, or manual therapy, consisting of mobilisations (high- and low velocity techniques, exercise therapy for the cervical and thoracic spine and postural correction. The primary outcome measures are the number of headache days and use of medication. Secondary outcome measures are severity of headache, functional status, sickness absence, use of other healthcare resources, active cervical range of motion, algometry, endurance of the neckflexor muscles and head posture. Follow-up assessments are conducted after 8 and 26 weeks. Discussion This is a pragmatic trial in which interventions are offered as they are carried out in everyday practice. This increases generalisability of results, but blinding of patients, GPs and therapists is not possible. The results of this trial will contribute to clinical decision making of the GP regarding referral to manual therapy in patients with chronic tension headache.

  4. Comparing the Influences of the D/H Ratio, Size, and Facade Design of an Enclosed Square on Its Perceptual Qualities as a Sustainable Urban Space in South Korea

    Directory of Open Access Journals (Sweden)

    Jaecheol Kim

    2017-04-01

    Full Text Available This study examines the dominance of the D/H ratio as a design element for an enclosed urban square, long claimed by numerous urban designers. It claims that like the D/H ratio, other design elements significantly affect the perceptual quality of an enclosed square, but their impacts differ according to the context in which they are applied. The study reviews the literature pertaining to enclosures as an urban design strategy and design elements for an enclosed urban square. Then it presents a comparative analysis of the impact of the D/H ratio and other design elements such as the size of the square and the facade design using a visual assessment survey with computer-simulated images of urban squares. Results of the analysis support the argument that like the D/H ratio, the square size and its facade design have a considerable but distinctly different influence on users’ perceptions of urban squares.

  5. Rationale and design of ASTEROID 2, a randomized, placebo- and active comparator-controlled study to assess the efficacy and safety of vilaprisan in patients with uterine fibroids.

    Science.gov (United States)

    Seitz, Christian; Bumbuliene, Žana; Costa, Ana Rosa; Heikinheimo, Oskari; Heweker, Andrea; Hudeček, Robert; Jacquemyn, Yves; Melis, Gian Benedetto; Parashar, Pooja; Rechberger, Tomasz; Sánchez, Antonio Cano; van Aken, Bart; Zatik, János; Gemzell-Danielsson, Kristina

    2017-04-01

    Uterine fibroids (UFs) may be treated with progesterone receptor modulators (PRMs), which have been shown to reduce heavy menstrual bleeding and the size of UFs. To date, one PRM (ulipristal acetate) has received regulatory approval for the treatment of UFs; therapy comprises intermittent treatment courses of up to 3months each, followed by a break to allow two menstruations to occur. We report the design of ASTEROID (Assess Safety and efficacy of vilaprisan in patients with uTERine fibrOIDs) 2, a phase 2 study examining the efficacy and safety of a novel PRM, vilaprisan, in women with UFs. In this randomized multi-arm study, vilaprisan (2mg daily) will be administered in different regimens: continuous treatment for 12 or 24weeks, or two 12-week treatment periods separated by a break to allow one menstruation to occur. Efficacy and safety will be compared with that of ulipristal acetate (5mg daily) and placebo. Patients randomized to receive placebo for 12weeks will also be given active treatment for 12weeks. The primary measure of efficacy will be amenorrhoea rate; secondary measures include time to normalized menstrual bleeding and percentage change in UF volume. Endometrial changes will be monitored throughout the study. The placebo- and active comparator-controlled trial ASTEROID 2 is the first study to evaluate systematically the efficacy and safety of different treatment regimens of PRMs in women with UFs. The findings of this study will direct the planning of future clinical trials of vilaprisan. Copyright © 2017 Bayer AG. Published by Elsevier Inc. All rights reserved.

  6. Comparative Analysis of Material Criteria in Neighborhood Sustainability Assessment Tools and Urban Design Guidelines: Cases of the UK, the US, Japan, and Korea

    National Research Council Canada - National Science Library

    Jungwon Yoon; Jiyoung Park

    2015-01-01

    .... As the notion of sustainable urban design has gained more significance, city governments have set their own guidelines for sustainable standards in urban design based on studies of sustainability assessment tools...

  7. A mobile application improves therapy-adherence rates in elderly patients undergoing rehabilitation: A crossover design study comparing documentation via iPad with paper-based control.

    Science.gov (United States)

    Mertens, Alexander; Brandl, Christopher; Miron-Shatz, Talya; Schlick, Christopher; Neumann, Till; Kribben, Andreas; Meister, Sven; Diamantidis, Clarissa Jonas; Albrecht, Urs-Vito; Horn, Peter; Becker, Stefan

    2016-09-01

    Medication adherence is crucial for success in the management of patients with chronic conditions. This study analyzes whether a mobile application on a tablet aimed at supporting drug intake and vital sign parameter documentation affects adherence in elderly patients.Patients with coronary heart disease and no prior knowledge of tablet computers were recruited. They received a personal introduction to the mobile application Medication Plan, installed on an Apple iPad. The study was conducted using a crossover design with 3 sequences: initial phase, interventional phase (28 days of using the app system), and comparative phase (28 days of using a paper diary). Users experienced the interventional and comparative phases alternately.A total of 24 patients (12 males; mean age 73.8 years) were enrolled in the study. The mean for subjectively assessed adherence (A14-scale; 5-point Likert scale, from "never" to "very often" which results in a score from 0 to 56) before the study was 50.0 (SD = 3.44). After both interventions there was a significant increase, which was more pronounced after the interventional phase (54.0; SD = 2.01) than after the comparative phase (52.6; SD = 2.49) (for all pairs after both interventions, P <0.001). Neither medical conditions nor the number of drug intake (amount and frequency of drug taking) per day affected subjective adherence. Logging data showed a significantly stronger adherence for the medication app than the paper system for both blood pressure recordings (P <0.001) and medication intake (P = 0.033). The majority of participants (n = 22) stated that they would like to use the medication app in their daily lives and would not need further assistance with the app.A mobile app for medication adherence increased objectively and subjectively measured adherence in elderly users undergoing rehabilitation. The findings have promising clinical implications: digital tools can assist chronic disease patients achieve adherence to

  8. Design on Thermal Shutdown Circuit with Hysteresis Comparator%基于迟滞比较器的过热保护电路设计

    Institute of Scientific and Technical Information of China (English)

    苏长江; 吴春瑜; 王绩伟; 温绍琨

    2012-01-01

    为了防止芯片过热,提高芯片可靠性和稳定性,采用0.5 μm CMOS工艺,设计了一种具有迟滞比较器的过热保护电路.由于采用了折叠式运放,使得比较器输入范围更大,灵敏度和迟滞性能更好.利用Cadence Spectre仿真工具对电路进行了仿真,结果表明电源电压为4.5~7V时,过温保护阚值变化量极小,表现出输出信号对电源的良好抑制.当温度超过130℃时,输出信号翻转,芯片停止工作;温度降低至90℃时,芯片恢复工作.此电路可以通过调整特定管子的尺寸而控制两个阈值电压的大小,从而避免热振荡的发生.%To prevent overheating of the chip and improve the reliability and stability of the chip, using a 0. 5 μm CMOS process, a thermal shutdown circuit with hysteresis comparator was designed. The structure of the folded cascade 0PA was used in the comparator, so the comparator had a large input range as well as better hysteresis performance and temperature sensitivity. The circuits ware simulated by the cadence spectre, the resuIts show that when the supply voltage is in the range of 4. 5 - 7 V, the threshold voltage of over-temperature protection changes in a small amount, which means that the output signal has a good power supply rejection. When the temperature exceeds 130 ℃ , the output signal turns over and the ship stops working. When the temperature falls down to 90 ℃ , the chip works again. This circuit can control the magnitude of two threshold voltages by adjusting size of specific transistor, and because of this special function it avoids the thermal swing.

  9. Comparative study of the binding pockets of mammalian proprotein convertases and its implications for the design of specific small molecule inhibitors

    Directory of Open Access Journals (Sweden)

    Sun Tian, Wu Jianhua

    2010-01-01

    Full Text Available Proprotein convertases are enzymes that proteolytically cleave protein precursors in the secretory pathway to yield functional proteins. Seven mammalian subtilisin/Kex2p-like proprotein convertases have been identified: furin, PC1, PC2, PC4, PACE4, PC5 and PC7. The binding pockets of all seven proprotein convertases are evolutionarily conserved and highly similar. Among the seven proprotein convertases, the furin cleavage site motif has recently been characterized as a 20-residue motif that includes one core region P6-P2´ inside the furin binding pocket. This study extended this information by examining the 3D structural environment of the furin binding pocket surrounding the core region P6-P2´ of furin substrates. The physical properties of mutations in the binding pockets of the other six mammalian proprotein convertases were compared. The results suggest that: 1 mutations at two positions, Glu230 and Glu257, change the overall density of the negative charge of the binding pockets, and govern the substrate specificities of mammalian proprotein convertases; 2 two proprotein convertases (PC1 and PC2 may have reduced sensitivity for positively charged residues at substrate position P5 or P6, whereas the substrate specificities of three proprotein convertases (furin, PACE4, and PC5 are similar to each other. This finding led to a novel design of a short peptide pattern for small molecule inhibitors: [K/R]-X-V-X-K-R. Compared with the widely used small molecule dec-RVKR-cmk that inhibits all seven proprotein convertases, a finely-tuned derivative of the short peptide pattern [K/R]-X-V-X-K-R may have the potential to more effectively inhibit five of the proprotein convertases (furin, PC4, PACE4, PC5 and PC7 compared to the remaining two (PC1 and PC2. The results not only provide insights into the molecular evolution of enzyme function in the proprotein convertase family, but will also aid the study of the functional redundancy of proprotein

  10. Basic research on design analysis methods for rotorcraft vibrations

    Science.gov (United States)

    Hanagud, S.

    1991-01-01

    The objective of the present work was to develop a method for identifying physically plausible finite element system models of airframe structures from test data. The assumed models were based on linear elastic behavior with general (nonproportional) damping. Physical plausibility of the identified system matrices was insured by restricting the identification process to designated physical parameters only and not simply to the elements of the system matrices themselves. For example, in a large finite element model the identified parameters might be restricted to the moduli for each of the different materials used in the structure. In the case of damping, a restricted set of damping values might be assigned to finite elements based on the material type and on the fabrication processes used. In this case, different damping values might be associated with riveted, bolted and bonded elements. The method itself is developed first, and several approaches are outlined for computing the identified parameter values. The method is applied first to a simple structure for which the 'measured' response is actually synthesized from an assumed model. Both stiffness and damping parameter values are accurately identified. The true test, however, is the application to a full-scale airframe structure. In this case, a NASTRAN model and actual measured modal parameters formed the basis for the identification of a restricted set of physically plausible stiffness and damping parameters.

  11. Structural requirements and basic design concepts for a two-stage winged launcher system (Saenger)

    Science.gov (United States)

    Kuczera, H.; Keller, K.; Kunz, R.

    1988-10-01

    An evaluation is made of materials and structures technologies deemed capable of increasing the mass fraction-to-orbit of the Saenger two-stage launcher system while adequately addressing thermal-control and cryogenic fuel storage insulation problems. Except in its leading edges, nose cone, and airbreathing propulsion system air intakes, Ti alloy-based materials will be the basis of the airframe primary structure. Lightweight metallic thermal-protection measures will be employed. Attention is given to the design of the large lower stage element of Saenger.

  12. Design of a comparative effectiveness evaluation of a culturally tailored versus standard community-based smoking cessation treatment program for LGBT smokers.

    Science.gov (United States)

    Matthews, Alicia K; McConnell, Elizabeth A; Li, Chien-Ching; Vargas, Maria C; King, Andrea

    2014-01-01

    Smoking prevalence rates among the lesbian, gay, bisexual, and transgender (LGBT) population are significantly higher than the general population. However, there is limited research on smoking cessation treatments in this group, particularly on culturally targeted interventions. Moreover, there are few interventions that address culturally specific psychosocial variables (e.g., minority stress) that may influence outcomes. This paper describes the protocol for a comparative effectiveness trial testing an evidence-based smoking cessation program, Courage to Quit, against a culturally tailored version for LGBT smokers, and examines the role of culturally specific psychosocial variables on cessation outcomes. To examine the effectiveness of a culturally targeted versus standard smoking cessation intervention, the study utilizes a 2-arm block, randomized, control trial (RCT) design. Adult LGBT participants (n = 400) are randomized to one of the two programs each consisting of a six-session group program delivered in a community center and an eight week supply of the transdermal nicotine patch. Four individualized telephone counseling sessions occur at weeks 2, 5, 7, and 9, at times of greatest risk for relapse. Study outcome measures are collected at baseline, and 1, 3, 6, and 12 months post quit date. Primary outcomes are expired air carbon monoxide verified 7-day point-prevalence quit rates at each measurement period. Secondary outcomes assess changes in cravings, withdrawal symptoms, smoking cessation self-efficacy, and treatment adherence. Additionally, study staff examines the role of culturally specific psychosocial variables on cessation outcomes using path analysis. Determining the efficacy of culturally specific versus standard evidence based approaches to smoking cessation is a critical issue facing the field today. This study provides a model for the development and implementation of a culturally tailored smoking cessation intervention for LGBT

  13. Effects of mental practice embedded in daily therapy compared to therapy as usual in adult stroke patients in Dutch nursing homes: design of a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Beurskens Anna J

    2007-10-01

    Full Text Available Abstract Background Mental practice as an additional cognitive therapy is getting increased attention in stroke rehabilitation. A systematic review shows some evidence that several techniques in which movements are rehearsed mentally might be effective but not enough to be certain. This trial investigates whether mental practice can contribute to a quicker and/or better recovery of stroke in two Dutch nursing homes. The objective is to investigate the therapeutic potential of mental practice embedded in daily therapy to improve individually chosen daily activities of adult stroke patients compared to therapy as usual. In addition, we will investigate prognostic variables and feasibility (process evaluation. Methods A randomised, controlled, observer masked prospective trial will be conducted with adult stroke patients in the (subacute phase of stroke recovery. Over a six weeks intervention period the control group will receive multi professional therapy as usual. Patients in the experimental group will be instructed how to perform mental practice, and will receive care as usual in which mental practice is embedded in physical, occupation and speech therapy sessions. Outcome will be assessed at six weeks and six months. The primary outcome measure is the patient-perceived effect on performance of daily activities as assessed by an 11-point Likert Scale. Secondary outcomes are: Motricity Index, Nine Hole Peg Test, Barthel Index, Timed up and Go, 10 metres walking test, Rivermead Mobility Index. A sample size of the patients group and all therapists will be interviewed on their opinion of the experimental program to assess feasibility. All patients are asked to keep a log to determine unguided training intensity. Discussion Advantages and disadvantages of several aspects of the chosen design are discussed. Trial registration ISRCTN27582267

  14. COMPARATION STUDY OF INSTANT NOODLE NONG SHIM KOREA AND INDOMIE INDONESIA AS THE FEFFECT OF PACKAGING DESIGN POINT OF INTEREST TO THE CONSUMER BRAND PREFERENCE

    Directory of Open Access Journals (Sweden)

    Listia Natadjaja

    2003-01-01

    Full Text Available Sudah sejak lama%2C masyarakat mengkonsumsi mie instant. Di Korea mi instan yang disebut Ramyon%2C adalah salah satu makanan yang popular dan banyak dijual di toko-toko kecil%2C supermarket%2C restoran dan kantin. Mi instan yang terkenal di Korea diproduksi oleh Nong Shim Co.%2C Ltd. Di Indonesia%2C kebanyakan orang mengkonsumsi mi instan dengan alasan praktis%2C cepat saji dan lain sebagainya. Indomie%2C yang diproduksi oleh PT. Indofood adalah merk nomor satu dan menjadi pemimpin pasar pada pasar mi instan. Dalam studi komparasi antara dua merk terkenal ini%2C perlu diketahui seberapa jauh peran desain kemasan dalam menarik minat konsumen terhadap pilihan merk. Abstract in Bahasa Indonesia : For a long time%2C people have consumed the instant noodle. In Korea%2C instant noodle%2C which is called Ramyon%2C is one of popular food and it is often seen in the retail shop%2C supermarket%2C restaurant and cafeteria. Instant noodle that has a famous brand in Korea is produce by Nong Shim Co.%2C Ltd. In Indonesia%2C many people have consumed the instant noodle with practice reason%2C fast serving%2C and etc. Indomie%2C produced by PT. Indofood%2C is the number one brand and become the market leader of instant noodle. Comparing at two famous brand of instant noodle%2C it is needed to be known how far the effect of packaging design can attract the consumer brand preference. desain kemasan%2C pilihan merk%2C mi instan.

  15. A KBE-enabled design framework for cost/weight optimization study of aircraft composite structures

    Science.gov (United States)

    Wang, H.; La Rocca, G.; van Tooren, M. J. L.

    2014-10-01

    Traditionally, minimum weight is the objective when optimizing airframe structures. This optimization, however, does not consider the manufacturing cost which actually determines the profit of the airframe manufacturer. To this purpose, a design framework has been developed able to perform cost/weight multi-objective optimization of an aircraft component, including large topology variations of the structural configuration. The key element of the proposed framework is a dedicated knowledge based engineering (KBE) application, called multi-model generator, which enables modelling very different product configurations and variants and extract all data required to feed the weight and cost estimation modules, in a fully automated fashion. The weight estimation method developed in this research work uses Finite Element Analysis to calculate the internal stresses of the structural elements and an analytical composite plate sizing method to determine their minimum required thicknesses. The manufacturing cost estimation module was developed on the basis of a cost model available in literature. The capability of the framework was successfully demonstrated by designing and optimizing the composite structure of a business jet rudder. The study case indicates the design framework is able to find the Pareto optimal set for minimum structural weight and manufacturing costin a very quick way. Based on the Pareto set, the rudder manufacturer is in conditions to conduct both internal trade-off studies between minimum weight and minimum cost solutions, as well as to offer the OEM a full set of optimized options to choose, rather than one feasible design.

  16. A Comparative Analysis of the Effects of Instructional Design Factors on Student Success in E-Learning: Multiple-Regression versus Neural Networks

    Science.gov (United States)

    Cebeci, Halil Ibrahim; Yazgan, Harun Resit; Geyik, Abdulkadir

    2009-01-01

    This study explores the relationship between the student performance and instructional design. The research was conducted at the E-Learning School at a university in Turkey. A list of design factors that had potential influence on student success was created through a review of the literature and interviews with relevant experts. From this, the…

  17. A comparative analysis of the effects of instructional design factors on student success in e-learning: multiple-regression versus neural networks

    Directory of Open Access Journals (Sweden)

    Halil Ibrahim Cebeci

    2009-12-01

    Full Text Available This study explores the relationship between the student performance and instructional design. The research was conducted at the E-Learning School at a university in Turkey. A list of design factors that had potential influence on student success was created through a review of the literature and interviews with relevant experts. From this, the five most import design factors were chosen. The experts scored 25 university courses on the extent to which they demonstrated the chosen design factors. Multiple-regression and supervised artificial neural network (ANN models were used to examine the relationship between student grade point averages and the scores on the five design factors. The results indicated that there is no statistical difference between the two models. Both models identified the use of examples and applications as the most influential factor. The ANN model provided more information and was used to predict the course-specific factor values required for a desired level of success.

  18. Analysis-Driven Design Optimization of a SMA-Based Slat-Cove Filler for Aeroacoustic Noise Reduction

    Science.gov (United States)

    Scholten, William; Hartl, Darren; Turner, Travis

    2013-01-01

    Airframe noise is a significant component of environmental noise in the vicinity of airports. The noise associated with the leading-edge slat of typical transport aircraft is a prominent source of airframe noise. Previous work suggests that a slat-cove filler (SCF) may be an effective noise treatment. Hence, development and optimization of a practical slat-cove-filler structure is a priority. The objectives of this work are to optimize the design of a functioning SCF which incorporates superelastic shape memory alloy (SMA) materials as flexures that permit the deformations involved in the configuration change. The goal of the optimization is to minimize the actuation force needed to retract the slat-SCF assembly while satisfying constraints on the maximum SMA stress and on the SCF deflection under static aerodynamic pressure loads, while also satisfying the condition that the SCF self-deploy during slat extension. A finite element analysis model based on a physical bench-top model is created in Abaqus such that automated iterative analysis of the design could be performed. In order to achieve an optimized design, several design variables associated with the current SCF configuration are considered, such as the thicknesses of SMA flexures and the dimensions of various components, SMA and conventional. Designs of experiment (DOE) are performed to investigate structural response to an aerodynamic pressure load and to slat retraction and deployment. DOE results are then used to inform the optimization process, which determines a design minimizing actuator forces while satisfying the required constraints.

  19. Specific treatment of problems of the spine (STOPS: design of a randomised controlled trial comparing specific physiotherapy versus advice for people with subacute low back disorders

    Directory of Open Access Journals (Sweden)

    Richards Matthew C

    2011-05-01

    Full Text Available Abstract Background Low back disorders are a common and costly cause of pain and activity limitation in adults. Few treatment options have demonstrated clinically meaningful benefits apart from advice which is recommended in all international guidelines. Clinical heterogeneity of participants in clinical trials is hypothesised as reducing the likelihood of demonstrating treatment effects, and sampling of more homogenous subgroups is recommended. We propose five subgroups that allow the delivery of specific physiotherapy treatment targeting the pathoanatomical, neurophysiological and psychosocial components of low back disorders. The aim of this article is to describe the methodology of a randomised controlled trial comparing specific physiotherapy treatment to advice for people classified into five subacute low back disorder subgroups. Methods/Design A multi-centre parallel group randomised controlled trial is proposed. A minimum of 250 participants with subacute (6 weeks to 6 months low back pain and/or referred leg pain will be classified into one of five subgroups and then randomly allocated to receive either physiotherapy advice (2 sessions over 10 weeks or specific physiotherapy treatment (10 sessions over 10 weeks tailored according to the subgroup of the participant. Outcomes will be assessed at 5 weeks, 10 weeks, 6 months and 12 months following randomisation. Primary outcomes will be activity limitation measured with a modified Oswestry Disability Index as well as leg and back pain intensity measured on separate 0-10 Numerical Rating Scales. Secondary outcomes will include a 7-point global rating of change scale, satisfaction with physiotherapy treatment, satisfaction with treatment results, the Sciatica Frequency and Bothersomeness Scale, quality of life (EuroQol-5D, interference with work, and psychosocial risk factors (Orebro Musculoskeletal Pain Questionnaire. Adverse events and co-interventions will also be measured. Data will be

  20. Specific treatment of problems of the spine (STOPS): design of a randomised controlled trial comparing specific physiotherapy versus advice for people with subacute low back disorders

    Science.gov (United States)

    2011-01-01

    Background Low back disorders are a common and costly cause of pain and activity limitation in adults. Few treatment options have demonstrated clinically meaningful benefits apart from advice which is recommended in all international guidelines. Clinical heterogeneity of participants in clinical trials is hypothesised as reducing the likelihood of demonstrating treatment effects, and sampling of more homogenous subgroups is recommended. We propose five subgroups that allow the delivery of specific physiotherapy treatment targeting the pathoanatomical, neurophysiological and psychosocial components of low back disorders. The aim of this article is to describe the methodology of a randomised controlled trial comparing specific physiotherapy treatment to advice for people classified into five subacute low back disorder subgroups. Methods/Design A multi-centre parallel group randomised controlled trial is proposed. A minimum of 250 participants with subacute (6 weeks to 6 months) low back pain and/or referred leg pain will be classified into one of five subgroups and then randomly allocated to receive either physiotherapy advice (2 sessions over 10 weeks) or specific physiotherapy treatment (10 sessions over 10 weeks) tailored according to the subgroup of the participant. Outcomes will be assessed at 5 weeks, 10 weeks, 6 months and 12 months following randomisation. Primary outcomes will be activity limitation measured with a modified Oswestry Disability Index as well as leg and back pain intensity measured on separate 0-10 Numerical Rating Scales. Secondary outcomes will include a 7-point global rating of change scale, satisfaction with physiotherapy treatment, satisfaction with treatment results, the Sciatica Frequency and Bothersomeness Scale, quality of life (EuroQol-5D), interference with work, and psychosocial risk factors (Orebro Musculoskeletal Pain Questionnaire). Adverse events and co-interventions will also be measured. Data will be analysed according to

  1. The Role of Engineering Design in Technological and 21st Century Competencies Capacity Building: Comparative Case Study in the Middle East, Asia, and Europe

    Directory of Open Access Journals (Sweden)

    Mahmoud Abdulwahed

    2017-03-01

    Full Text Available Engineering design is considered an effective means for developing engineering technical skills. Normally, engineering design is conducted in teams and is a collaborative open-ended approach under constraints. This nature of engineering design involves engagement of several interpersonal, cognitive, and management skills or competencies such as teamwork, communications, decision making, problem solving, etc. While modern engineers are supposed to be technically competent, they need to posses a wide set of interpersonal, cognitive, and management competencies to function effectively in the workplace. Increasingly there has been more deployment of engineering design competitions (EDCs in engineering education to address some gaps in current curricula system. In this study, the impact of a complex engineering design competition on developing 21st century competencies of engineering and technology talent is investigated. A mix of quantitative and qualitative methods in the approach to self-reporting perceptions were utilized. Data was collected through interviews from students and faculty, and through surveys from students. Triangulating quantitative and qualitative data from students and faculty indicate that the investigated EDC have positive impact on a large set of 21st century engineering and technology competencies, this has been consistent across groups of students from the EU, Middle East, and Asia, as well as across genders. This is one of the few available investigations that sheds light in further depth on the impact of engineering design on non-technical skills.

  2. Comparative Research on Regional Competitiveness of Industrial Design Industry in China%工业设计产业区域竞争优势比较研究

    Institute of Scientific and Technical Information of China (English)

    王汉友

    2012-01-01

    运用波特钻石模型理论确定影响设计产业竞争优势的关键因素,开发量表并设计问卷,完成珠三角和长三角设计产业竞争优势比较研究。分析显示:两地制造业和国际设计需求相对不足,设计企业经营管理和竞争策略颇为类似,政府设计促进政策实效不佳;但长三角在设计师薪酬、产业配套和发展机遇方面优于珠三角,其产业整体竞争力亦强于珠三角。%The key factors influencing design industries' competitiveness is demonstrated using diamond model by M.E. Porter to develop scales and to design questionnaire, The statistics analysis reveals that there are the common grounds between the two regions, such as the limited international and manufacturing sector' s design need and the similar management and competitive policies of design houses and the ineffective governmental design policies. Whereas the design industry in Yangtze River Delta excels the one in Pearl River Delta on designers' salary and relevant supporting industries and developing chance, the former' s comprehensive competitiveness is superior to the latter as well.

  3. Industrial Upgrading in the Apparel Value Chain and the Role of Designer in the Transition: comparative analysis of Sri Lanka and Hong Kong

    Directory of Open Access Journals (Sweden)

    Sumith Gopura

    2016-11-01

    Full Text Available The apparel industry is a major export industry in Sri Lanka that depends upon labour intensive manufacturing. The Sri Lankan apparel industry is transitioning from Cut, Make, Trims (CMT assembly and Original Equipment Manufacturing (OEM to Original Design Manufacturing (ODM and Original Brand Manufacturing (OBM, experiencing the economic benefits of apparel product export. The transition relies on having expert professionals who can provide creative, commercial, technical, and leadership skills in the process. In order to identify the creative roles and responsibilities that can contribute to the industrial upgrading process in Sri Lanka, this paper first provides an analysis of the global apparel value chain and the journeys of the countries with newly industrialized economies (NIEs in the region. Second, a comparison of Hong Kong and Sri Lankan apparel industries contextualises the development of fashion design within each nation’s industry as a competitive advantage. In each country we examine three factors that demonstrate growth in fashion design: development of fashion design education; development of exportable own brands; and the establishment of local showcases to a global audience. The examples of both Hong Kong and Sri Lanka demonstrate the ways in which creative roles may act as a bridge between production and marketing networks, buyers and producers in maintaining and building industry value-adding for highly sophisticated and competitive fashion production systems. Although the Sri Lankan apparel industry has not progressed as far as Hong Kong in this arena, evidence suggests the industry is actively growing design capabilities

  4. ConservedPrimers 2.0: a high-throughput pipeline for comparative genome referenced intron-flanking PCR primer design and its application in wheat SNP discovery.

    Science.gov (United States)

    You, Frank M; Huo, Naxin; Gu, Yong Q; Lazo, Gerard R; Dvorak, Jan; Anderson, Olin D

    2009-10-13

    In some genomic applications it is necessary to design large numbers of PCR primers in exons flanking one or several introns on the basis of orthologous gene sequences in related species. The primer pairs designed by this target gene approach are called "intron-flanking primers" or because they are located in exonic sequences which are usually conserved between related species, "conserved primers". They are useful for large-scale single nucleotide polymorphism (SNP) discovery and marker development, especially in species, such as wheat, for which a large number of ESTs are available but for which genome sequences and intron/exon boundaries are not available. To date, no suitable high-throughput tool is available for this purpose. We have developed, the ConservedPrimers 2.0 pipeline, for designing intron-flanking primers for large-scale SNP discovery and marker development, and demonstrated its utility in wheat. This tool uses non-redundant wheat EST sequences, such as wheat contigs and singleton ESTs, and related genomic sequences, such as those of rice, as inputs. It aligns the ESTs to the genomic sequences to identify unique colinear exon blocks and predicts intron lengths. Intron-flanking primers are then designed based on the intron/exon information using the Primer3 core program or BatchPrimer3. Finally, a tab-delimited file containing intron-flanking primer pair sequences and their primer properties is generated for primer ordering and their PCR applications. Using this tool, 1,922 bin-mapped wheat ESTs (31.8% of the 6,045 in total) were found to have unique colinear exon blocks suitable for primer design and 1,821 primer pairs were designed from these single- or low-copy genes for PCR amplification and SNP discovery. With these primers and subsequently designed genome-specific primers, a total of 1,527 loci were found to contain one or more genome-specific SNPs. The ConservedPrimers 2.0 pipeline for designing intron-flanking primers was developed and its

  5. How Funding Instability Affects Army Programs

    Science.gov (United States)

    2007-01-01

    other D models are remanufactured A-, B-, and C-model Chinooks. Compared with its predecessors, the CH-47D features composite rotor blades, an...Aviation Intermediate Maintenance. Comanche’s advanced airframe design incorporates composite airframe structures, a bearingless main rotor system...that significantly improves airlift responsiveness. Significant features of the C-17 include: super-critical wing design and winglets to reduce drag

  6. A New Design Methodology of Low Power Asynchronous Comparator%一种新型低功耗异步比较器的设计方法

    Institute of Scientific and Technical Information of China (English)

    姜小波; 叶德盛

    2012-01-01

    Two types of low-power asynchronous comparators named asynchronous ripple comparator and pre-stop asynchronous comparator are proposed based on the statistical characteristic of input data in the paper. The asynchronous ripple comparator stops computing at the first unequal bit, but it has to deliver the result to the LSB. The pre-stop asynchronous comparator is proposed by revising the truth table based on the new 2-bit comparison unit and stop judgment circuit. It can stop comparing at the first unequal bit and obtain the result immediately. The proposed and contrasn've comparators (BCL comparator and clock-gating comparator) are implemented with SMIC 0.18μm process. Simulation results show that the proposed pre-stop asynchronous comparator features the lowest power.It saves 87.1% ,84.5% and 37.5% ,28.6% power respectively compared to the synchronous BCL comparator and clock-gating comparator with random data and data from LDPC decoder.%本文利用输入数据的统计特性,设计了两种低功耗异步比较器——异步行波比较器和提前终止异步比较器.异步行波比较器从第一个不相等的数位开始停止运算,但要把结果传到最低位,消耗部分功耗.提前终止异步比较器通过修改真值表,基于新的比较单元电路和终止判断电路,在第一个不相等的数位停止运算并立即输出比较结果,节省不必要的功耗.新设计的异步比较器和用于对比的同步比较器(BCL比较器和门控时钟比较器)均用SMIC0.18μm工艺实现.仿真结果表明,提前终止异步比较器功耗最低,与同步BCL比较器和门控时钟比较器相比,在随机数据和来自LDPC解码器的数据下,分别节省了87.1%、84.5%和37.5%、28.6%的功耗.

  7. An analysis of the efficiency of the functional matching between a flying wing MAV airframe and different types of micro propellers

    Directory of Open Access Journals (Sweden)

    Ionică CÎRCIU

    2011-03-01

    Full Text Available This paper aims to present specific methods for optimizing the design of micro propellersfor small Reynolds numbers. In order to better understand the aim of this contribution, the effects of amicro propeller on the aerodynamic surfaces of a micro air vehicle (for example a flying wingconfiguration are presented together with the analysis of the specific tools for the design of micropropellers. The final part aims to renew the interest in predicting the influence of the propeller-wingflow interaction on the aerodynamic characteristics of deflected slipstream and small flying wingMAV.

  8. Comparative safety testing of genetically modified foods in a 90-day rat feeding study design allowing the distinction between primary and secondary effects of the new genetic event

    DEFF Research Database (Denmark)

    Knudsen, Ib; Poulsen, Morten

    2007-01-01

    high dose level and a dietary design based upon compositional data on the GM food and toxicity data on the gene product is sensitive and specific enough to verify the presence/absence of the biological/nutritional/toxicological effects of the novel gene insert and further by the use of spiking able......This article discusses the wider experiences regarding the usefulness of the 90-day rat feeding study for the testing of whole foods from genetically modified (GM) plant based on data from a recent EU-project [Poulsen, M., Schroder, M., Wilcks, A., Kroghsbo, S., Lindecrona, R.H., Miller, A......., Frenzel, T., Danier, J., Rychlik, M., Shu, Q., Emami, K., Taylor, M., Gatehouse, A., Engel, K.-H., Knudsen, I., 2007a. Safety testing of GM-rice expressing PHA-E lectin using a new animal test design. Food Chem. Toxicol. 45, 364-377; Poulsen, M., Kroghsbo, S., Schroder, M., Wilcks, A., Jacobsen, H...

  9. Industrial Upgrading in the Apparel Value Chain and the Role of Designer in the Transition: comparative analysis of Sri Lanka and Hong Kong

    OpenAIRE

    Sumith Gopura; Alice Payne; Laurie Buys

    2016-01-01

    The apparel industry is a major export industry in Sri Lanka that depends upon labour intensive manufacturing. The Sri Lankan apparel industry is transitioning from Cut, Make, Trims (CMT) assembly and Original Equipment Manufacturing (OEM) to Original Design Manufacturing (ODM) and Original Brand Manufacturing (OBM), experiencing the economic benefits of apparel product export. The transition relies on having expert professionals who can provide creative, commercial, technical, an...

  10. Comparative Analysis of Material Criteria in Neighborhood Sustainability Assessment Tools and Urban Design Guidelines: Cases of the UK, the US, Japan, and Korea

    OpenAIRE

    Yoon, Jungwon; Park, Jiyoung

    2015-01-01

    Sustainability assessment tools have been developed for building-scale sustainability since the 1990s. Several systems, such as BREEAM (Building Research Establishment Environmental Assessment Methodology), LEED (Leadership in Energy and Environmental Design) and CASBEE (Comprehensive Assessment System for Built Environment Efficiency), are widely used and have been upgraded and adapted to large-scale development. BREEAM Communities, LEED Neighborhood Development and CASBEE for Urban Developm...

  11. Comparative Analysis of Virtual 3-D Visual Display Systems Contributions to Cross-Functional Team Collaboration in a Product Design Review Environment

    Science.gov (United States)

    1998-01-01

    76 subject interacted with the VE. These researchers also have explored application of neurolinguistic programming to quantify the sense of presence...model that a user forms of how a computer system or program works. It can be conceived as the users’ understanding of the relationships of between the...revise the program strategy. 36 Another important objective of design reviews is to integrate knowledge from various functional areas into one common

  12. Using computerised surface wound mapping to compare the potential medical effectiveness of Enhanced Protection Under Body Armour Combat Shirt collar designs.

    Science.gov (United States)

    Breeze, John; Allanson-Bailey, L C; Hunt, N C; Delaney, R; Hepper, A E; Lewis, E A

    2015-03-01

    Protecting the neck from explosively propelled fragments has traditionally been achieved through a collar attached to the ballistic vest. An Enhanced Protection Under Body Armour Combat Shirt (EP-UBACS) collar has been identified as an additional method of providing neck protection but limited evidence as to its potential medical effectiveness exists to justify its procurement. Entry wound locations and resultant medical outcomes were determined using Abbreviated Injury Scale (AIS) for all fragmentation neck wounds sustained by UK soldiers between 01 January 2010 and 31 December 2011. Data were prospectively entered into a novel computerised tool base and comparisons made between three EP-UBACS neck collar designs in terms of predicted reduction in AIS scores. All collars reduced AIS scores, with the greatest reduction provided by designs incorporating increased standoff from the neck and an additional semi-circle of ballistic material underneath the collar at the front and back. This technique confirms that reinforcing the neck collar of an EP-UBACS would be expected to reduce injury severity from neck wounds. However, without knowledge of entry wound locations for injuries to other body areas as well as the use of AIS scores without clinical or pathological verification its further use in the future may be limited. The ability to overlay any armour design onto a standardised human was potentially the most useful part of this tool and we would recommend developing this technique using underlying anatomical structures and not just the skin surface. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  13. Pancreatitis, very early compared with normal start of enteral feeding (PYTHON trial): design and rationale of a randomised controlled multicenter trial

    NARCIS (Netherlands)

    Bakker, O.J.; Santvoort, H.C. van; Brunschot, S. van; Ahmed Ali, U.; Besselink, M.G.; Boermeester, M.A.; Bollen, T.L.; Bosscha, K.; Brink, M.A.; Dejong, C.H.; Geenen, E.J. van; Goor, H. van; Heisterkamp, J.; Houdijk, A.P.; Jansen, J.M.; Karsten, T.M.; Manusama, E.R.; Nieuwenhuijs, V.B.; Ramshorst, B. van; Schaapherder, A.F.; Schelling, G.P. van der; Spanier, M.B.; Tan, A.; Vecht, J.; Weusten, B.L.; Witteman, B.J.; Akkermans, L.M.; Gooszen, H.G.

    2011-01-01

    BACKGROUND: In predicted severe acute pancreatitis, infections have a negative effect on clinical outcome. A start of enteral nutrition (EN) within 24 hours of onset may reduce the number of infections as compared to the current practice of starting an oral diet and EN if necessary at 3-4 days after

  14. Pancreatitis, very early compared with normal start of enteral feeding (PYTHON trial) : design and rationale of a randomised controlled multicenter trial

    NARCIS (Netherlands)

    Bakker, Olaf J.; van Santvoort, Hjalmar C.; van Brunschot, Sandra; Ali, Usama Ahmed; Besselink, Marc G.; Boermeester, Marja A.; Bollen, Thomas L.; Bosscha, Koop; Brink, Menno A.; Dejong, Cornelis H.; van Geenen, Erwin J.; van Goor, Harry; Heisterkamp, Joos; Houdijk, Alexander P.; Jansen, Jeroen M.; Karsten, Thom M.; Manusama, Eric R.; Nieuwenhuijs, Vincent B.; van Ramshorst, Bert; Schaapherder, Alexander F.; van der Schelling, George P.; Spanier, Marcel B. M.; Tan, Adriaan; Vecht, Juda; Weusten, Bas L.; Witteman, Ben J.; Akkermans, Louis M.; Gooszen, Hein G.

    2011-01-01

    Background: In predicted severe acute pancreatitis, infections have a negative effect on clinical outcome. A start of enteral nutrition (EN) within 24 hours of onset may reduce the number of infections as compared to the current practice of starting an oral diet and EN if necessary at 3-4 days after

  15. Pancreatitis, very early compared with normal start of enteral feeding (PYTHON trial): design and rationale of a randomised controlled multicenter trial

    NARCIS (Netherlands)

    Bakker, O.J.; van Santvoort, H.C.; van Brunschot, S.; Ali, U.A.; Besselink, M.G.; Boermeester, M.A.; Bollen, T.L.; Bosscha, K.; Brink, M.A.; Dejong, C.H.; van Geenen, E.J.; van Goor, H.; Heisterkamp, J.; Houdijk, A.P.; Jansen, J.M.; Karsten, T.M.; Manusama, E.R.; Nieuwenhuijs, V.B.; van Ramshorst, B.; Schaapherder, A.F.; van der Schelling, G.P.; Spanier, M.B.M.; Tan, A.; Vecht, J.; Weusten, B.L.; Witteman, B.J.; Akkermans, L.M.; Gooszen, H.G.

    2011-01-01

    ABSTRACT: BACKGROUND: In predicted severe acute pancreatitis, infections have a negative effect on clinical outcome. A start of enteral nutrition (EN) within 24 hours of onset may reduce the number of infections as compared to the current practice of starting an oral diet and EN if necessary at 3-4

  16. Design of a robotized workstation making use of the integration of CAD models and Robotic Simulation software as way of pairing and comparing real and virtual environments

    Directory of Open Access Journals (Sweden)

    Velíšek Karol

    2017-01-01

    Full Text Available Over the last years, there has been an increasing tendency and pressure on the faster implementation robotic devices and systems in manufacturing. Such transition involves several disciplines starting with the prototyping of CAD models itself. The paper addresses the creation of CAD models and is mainly aimed at their integration in a given simulation environment according to the conception and guidelines of Industry 4.0, where the part itself becomes the entity carrying most of the needed information at any time of a production process. The creation of such CAD models is key for the further and better customization of simulations. In other to better exemplify all this, the paper describes the whole process of “virtual to real life implementation” of a given robotized workplace needed to be developed at the Institute. The design of such robotized workplace included the use of an ABB IRB 120 robot and several other devices which were all designed, simulated and analyzed in a virtual environment before the final development and implementation. This paper helped demonstrating the importance of having exactly the same model (real and virtual with respect to the success of the offline simulations.

  17. Computer-aided design of negative allosteric modulators of metabotropic glutamate receptor 5 (mGluR5): Comparative molecular field analysis of aryl ether derivatives.

    Science.gov (United States)

    Selvam, Chelliah; Thilagavathi, Ramasamy; Narasimhan, Balasubramanian; Kumar, Pradeep; Jordan, Brian C; Ranganna, Kasturi

    2016-02-15

    The metabotropic glutamate receptors (mGlu receptors) have emerged as attractive targets for number of neurological and psychiatric disorders. Recently, mGluR5 negative allosteric modulators (NAMs) have gained considerable attention in pharmacological research. Comparative molecular field analysis (CoMFA) was performed on 73 analogs of aryl ether which were reported as mGluR5 NAMs. The study produced a statistically significant model with high correlation coefficient and good predictive abilities.

  18. Comparative evaluation of pressure generated on a simulated maxillary oral analog by impression materials in custom trays of different spacer designs: An in vitro study

    OpenAIRE

    Sakshi Chopra; Narendra Kumar Gupta; Amrit Tandan; Ravi Dwivedi; Swati Gupta; Garima Agarwal

    2016-01-01

    Introduction: Literature reveals that masticatory load on denture bearing tissues through complete dentures should be maximum on primary stress bearing areas and least on relief area in accordance with the histology of underlying tissues. A study to validate the existing beliefs was planned to compare the pressure on mucosa using selective pressure technique and minimal pressure technique, with the incorporation of two different impression materials utilizing the pressure sensors during secon...

  19. The ExStroke Pilot Trial: rationale, design, and baseline data of a randomized multicenter trial comparing physical training versus usual care after an ischemic stroke

    DEFF Research Database (Denmark)

    Krarup, L.H.; Gluud, C.; Truelsen, T.

    2008-01-01

    of increasing stroke patients' level of physical activity and secondarily to associate the level of physical activity to the risk of recurrent stroke, myocardial infarction, and all-cause mortality in the two groups. We describe the rationale, design, and baseline data of the ExStroke Pilot Trial. METHODS......INTRODUCTION: A high level of physical activity is associated with a decreased risk of first stroke and physical activity modifies recognized stroke risk factors and is recommended for stroke survivors. Available research shows that stroke patients can increase their level of physical performance...... over a short period. When the intervention period is over, physical performance often declines towards baseline level. Currently, there is no evidence on the association between physical activity and the risk of recurrent stroke. The ExStroke Pilot Trial is a randomized clinical trial with the aim...

  20. Recombinant FSH Compared to Clomiphene Citrate as the First-Line in Ovulation Induction in Polycystic Ovary Syndrome Using Newly Designed Pens: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Batool Hossein-Rashidi

    2016-05-01

    Full Text Available Objective: Since there is still controversy regarding the best first-line choice for ovulation induction (OI other than clomiphene citrate (CC in infertile women diagnosed with polycystic ovary syndrome (PCOS, the aim of the present study was to compare recombinant human FSH with CC as the first course of OI in these women.Materials and methods: In this pilot randomized controlled trial, 104 infertile women diagnosed with PCOS were randomized in two groups to receive either CC with the dose of 100mg per day from day 3 of a spontaneous or progestin-induced menstruation for 5 days or rFSH with the starting dose of 50 IU daily {and weekly dose increment of as low as 12.5 IU}, on the day4 of the cycle. They were assessed during a single OI course. The pregnancy rate (PR and live birth rate (LBR were the primary outcomes. The follicular response, endometrial thickness, cancellation of the cycles and ovarian hyper stimulation (OHSS rate were the secondary outcomes.Results: Analyzing data of 96 patients using Chi2 and Fischer’s Exact test (44 in rFSH group and 52 in CC group, both PR and LBR were comparable in the two groups {13.6% vs. 9.6% and 11.4% vs. 9.6% respectively}, with the difference not to be significant (p > 0.05. No cases of OHSS or multiple gestations happened during the treatment course.Conclusion: It seems that rFSH is as efficacious as CC while not with more complications for the first-line OI in infertile women with PCOS. However, due to the limitations of the present study including the small population and the single cycle of treatment, our results did not come out to prove this and more studies with larger study population are needed to compare the cumulative PR and LBR.

  1. 高共模输入电平的迟滞比较器设计%Design of Hysteresis Comparator with High Common Mode Input Level

    Institute of Scientific and Technical Information of China (English)

    鞠家欣; 张晋芳; 廖永波; 鲍嘉明; 杨兵

    2011-01-01

    A novel hysteresis comparator based on the bipolar technology was proposed. This comparator has the advantages of high common mode level and low power dissipation that the traditional circuit structure possesses. In comparison to the traditional circuit, an emitter follower is reduced. In addition, in order to remain the stability of the two-stage operational amplifier in this hysteresis comparator, the frequency compensation was studied. The circuit stability was simulated, and the phase margin attained 60°. This hysteresis comparator was realized by CSMC 1 u.m bipolar technology. The measured results show that the upper threshold voltage is 7. 4 V, the lower threshold voltage 6. 92 V, the hysteresis voltage is 0. 48 V, the output high level is about 0. 76 V, and the circuit works stably.%提出了一种新颖的基于双极工艺的迟滞比较器,该电路在保持了传统电路的高共模输入电平和低功耗的优点的同时,在电路结构上比传统的电路节省了一级射随器.此外,为了保证该迟滞比较器中两级运算放大器的稳定性还进行了频率补偿的研究,并对该电路的稳定性进行了仿真,其仿真结果保证了60°的相位裕度.该迟滞比较器的电路使用华润上华1 μm双极晶体管工艺实现,芯片测试结果表明,其上阈值点为7.4V,下阈值点为6.92 V,迟滞电压约为0.48 V,输出高电平约为0.76 V,电路工作稳定.

  2. Overview: Applications of numerical optimization methods to helicopter design problems

    Science.gov (United States)

    Miura, H.

    1984-01-01

    There are a number of helicopter design problems that are well suited to applications of numerical design optimization techniques. Adequate implementation of this technology will provide high pay-offs. There are a number of numerical optimization programs available, and there are many excellent response/performance analysis programs developed or being developed. But integration of these programs in a form that is usable in the design phase should be recognized as important. It is also necessary to attract the attention of engineers engaged in the development of analysis capabilities and to make them aware that analysis capabilities are much more powerful if integrated into design oriented codes. Frequently, the shortcoming of analysis capabilities are revealed by coupling them with an optimization code. Most of the published work has addressed problems in preliminary system design, rotor system/blade design or airframe design. Very few published results were found in acoustics, aerodynamics and control system design. Currently major efforts are focused on vibration reduction, and aerodynamics/acoustics applications appear to be growing fast. The development of a computer program system to integrate the multiple disciplines required in helicopter design with numerical optimization technique is needed. Activities in Britain, Germany and Poland are identified, but no published results from France, Italy, the USSR or Japan were found.

  3. Comparative study on the charge-trapping properties of TaAlO and ZrAlO high-k composites with designed band alignment

    Directory of Open Access Journals (Sweden)

    W. Lu

    2015-08-01

    Full Text Available The charge-trapping memory (CTM structures Pt/Al2O3/TaAlO/Al2O3/p-Si and Pt/Al2O3/ZrAlO/Al2O3/p-Si were fabricated by using rf-sputtering and atomic layer deposition techniques, in which the potentials at the bottom of the conduction band (PBCB of high-k composites TaAlO and ZrAlO were specially designed. With a lower PBCB difference between TaAlO and p-Si than that between ZrAlO and p-Si, TaAlO CTM device shows a better charge-trapping performance. A density of trapped charges 2.88 × 1013/cm2 at an applied voltage of ±7 V was obtained for TaAlO CTM device, and it could keep about 60% of initially trapped charges after 10 years. It was suggested that the PBCB difference between high-k composite and p-Si dominates their charge-trapping behaviors.

  4. The Columbus Knee System: 4-Year Results of a New Deep Flexion Design Compared to the NexGen Full Flex Implant

    Directory of Open Access Journals (Sweden)

    D. Goebel

    2012-01-01

    Full Text Available The Columbus knee system is designed as a standard knee implant to allow high flexion without additional bone resection. Between August, 2004 and March, 2010 we performed 109 total knee arthroplasties of the Columbus knee system in 101 consecutive patients suffering from primary arthrosis of the knee. Mean age was 72.4 years in women and 70.3 years in men. Mean followup was 47.3 months. The 4-year results of a group of patients who received the NexGen Full Flex implant operated by the same surgeon were used for comparison. Mean total knee score was Columbus: 175.6 and NexGen Flex: 183.4; =0.037. Mean operation time was 53 min for Columbus and 66 min for NexGen Flex; 0.05. Radiological assessment showed no signs of loosening for both groups. Therefore, the Columbus knee system can be recommended for flexion angles up to 140∘.

  5. The rationale, design, and baseline characteristics of PREVENT-DM: A community-based comparative effectiveness trial of lifestyle intervention and metformin among Latinas with prediabetes.

    Science.gov (United States)

    Perez, Alberly; Alos, Victor A; Scanlan, Adam; Maia, Catarina M; Davey, Adam; Whitaker, Robert C; Foster, Gary D; Ackermann, Ronald T; O'Brien, Matthew J

    2015-11-01

    Promotora Effectiveness Versus Metformin Trial (PREVENT-DM) is a randomized comparative effectiveness trial of a lifestyle intervention based on the Diabetes Prevention Program delivered by community health workers (or promotoras), metformin, and standard care. Eligibility criteria are Hispanic ethnicity, female sex, age ≥ 20 years, fluent Spanish-speaking status, BMI ≥ 23 kg/m(2), and prediabetes. We enrolled 92 participants and randomized them to one of the following three groups: standard care, DPP-based lifestyle intervention, or metformin. The primary outcome of the trial is the 12-month difference in weight between groups. Secondary outcomes include the following cardiometabolic markers: BMI, waist circumference, blood pressure, and fasting plasma glucose, hemoglobin A1C (HbA1c), total cholesterol, triglycerides, LDL cholesterol, HDL cholesterol, and insulin. PREVENT-DM participants are socioeconomically disadvantaged Latinas with a mean annual household income of $15,527 ± 9922 and educational attainment of 9.7 ± 3.6 years. Eighty-six percent of participants are foreign born, 20% have a prior history of gestational diabetes, and 71% have a first-degree relative with diagnosed diabetes. At baseline, PREVENT-DM participants had a mean age of 45.1 ± 12.5 years, weight of 178.8 ± 39.3 lbs, BMI of 33.3 ± 6.5 kg/m(2), HbA1c of 5.9 ± 0.2%, and waist circumference of 97.4 ± 11.1cm. Mean baseline levels of other cardiometabolic markers were normal. The PREVENT-DM study successfully recruited and randomized an understudied population of Latinas with prediabetes. This trial will be the first U.S. study to test the comparative effectiveness of metformin and lifestyle intervention versus standard care among prediabetic adults in a "real-world" setting.

  6. Comparing growth rate in a mixed plantation (walnut, poplar and nurse trees with different planting designs: results from an experimental plantation in northern Italy

    Directory of Open Access Journals (Sweden)

    Francesco Pelleri

    2013-12-01

    Full Text Available 800x600 Results of a mixed plantation with poplar, walnut and nurse trees established in winter 2003 in Northern Italy, are reported. Main tree species (poplar and walnut were planted according to a rectangular design (10 x 11m, with different spacings and alternate lines. The experimental trial was carried out to verify the following working hypotheses: (i possibility to combine main trees with different growth levels (common walnut, hybrid walnut, and different poplar clones and test two different poplar and walnut spacings (5.0 and 7.4 m in the same plantation; (ii opportunity to reduce cultivation’s workload, in comparison with poplar monoculture, using mixtures with different poplar clones and N-fixing nurse trees; (iii verifying the growth pattern of two new poplar clones in comparison with the traditional clones cultivated for different purposes in Italy.The use of different valuable crop trees’ mixtures intercropped with nurse trees and shrubs (including N-fixing trees allows to decrease the cultivation’s workload. In fact, a heavy reduction of cultural practices - fertilizers, weed control, irrigation and pesticides applications (-61% are the main concurrent, supplementary benefits. The best growth performances (DBH and tree height, associated with the higher competition towards walnuts, were recorded with the new clones Lena and Neva in comparison with the I214 and Villafranca. The closer spacing (5 m between poplar and walnut trees was found to be unsuited to get merchantable poplars sized 30 cm without developing a heavy competition towards walnut trees. The wider spacing (7.4 m resulted vice versa suitable to get poplar trees sized as requested by veneer factories and to maintain an acceptable competitive level with walnut. Within this plantation design, a shorter rotation (8 yrs is needed for Lena and Neva clones in comparison with I214 and Villafranca (10 yrs. Walnut intercropped with poplar showed cone-shaped crowns, light

  7. Comparative safety testing of genetically modified foods in a 90-day rat feeding study design allowing the distinction between primary and secondary effects of the new genetic event.

    Science.gov (United States)

    Knudsen, Ib; Poulsen, Morten

    2007-10-01

    This article discusses the wider experiences regarding the usefulness of the 90-day rat feeding study for the testing of whole foods from genetically modified (GM) plant based on data from a recent EU-project [Poulsen, M., Schrøder, M., Wilcks, A., Kroghsbo, S., Lindecrona, R.H., Miller, A., Frenzel, T., Danier, J., Rychlik, M., Shu, Q., Emami, K., Taylor, M., Gatehouse, A., Engel, K.-H., Knudsen, I., 2007a. Safety testing of GM-rice expressing PHA-E lectin using a new animal test design. Food Chem. Toxicol. 45, 364-377; Poulsen, M., Kroghsbo, S., Schrøder, M., Wilcks, A., Jacobsen, H., Miller, A., Frenzel, T., Danier, J., Rychlik, M., Shu, Q., Emami, K., Sudhakar, D., Gatehouse, A., Engel, K.-H., Knudsen, I., 2007b. A 90-day safety in Wistar rats fed genetically modified rice expressing snowdrop lectin Galanthus nivalis (GNA). Food Chem. Toxicol. 45, 350-363; Schrøder, M., Poulsen, M., Wilcks, A., Kroghsbo, S., Miller, A., Frenzel, T., Danier, J., Rychlik, M., Emami, K., Gatehouse, A., Shu, Q., Engel, K.-H., Knudsen, I., 2007. A 90-day safety study of genetically modified rice expressing Cry1Ab protein (Bacillus thuringiensis toxin) in Wistar rats. Food Chem. Toxicol. 45, 339-349]. The overall objective of the project has been to develop and validate the scientific methodology necessary for assessing the safety of foods from genetically modified plants in accordance with the present EU regulation. The safety assessment in the project is combining the results of the 90-day rat feeding study on the GM food with and without spiking with the pure novel gene product, with the knowledge about the identity of the genetic change, the compositional data of the GM food, the results from in-vitro/ex-vivo studies as well as the results from the preceding 28-day toxicity study with the novel gene product, before the hazard characterisation is concluded. The results demonstrated the ability of the 90-day rat feeding study to detect the biological/toxicological effects of the

  8. Design of a randomized controlled trial to compare debridement to observation of chondral lesions encountered during partial meniscectomy: The ChAMP (Chondral Lesions And Meniscus Procedures) Trial.

    Science.gov (United States)

    Bisson, Leslie J; Kluczynski, Melissa A; Wind, William M; Fineberg, Marc S; Bernas, Geoffrey A; Rauh, Michael A; Marzo, John M; Smolinski, Robert J

    2015-11-01

    Few studies have examined whether chondral lesions encountered in patients undergoing meniscectomy should be surgically treated. The primary aim of the ChAMP (Chondral Lesions And Meniscus Procedures) Trial is to determine whether there is a difference in knee pain between patients undergoing debridement versus observation of chondral lesions encountered during arthroscopic meniscectomy. This paper describes the rationale and study design for the ChAMP Trial. The ChAMP Trial is a randomized controlled trial of patients aged 30 and older undergoing partial meniscectomy and randomly allocated to debridement (CL-Deb, N=98) or observation (CL-Obs, N=92) of chondral lesions identified during surgery and deemed to be significant (Outerbridge Grade II-IV). Patients and data collectors were unaware of treatment allocation until completion of the study. Patients with surgically insignificant (Outerbridge Grade I) chondral lesions or no chondral lesions were included as a third non-randomized comparison group (NoCL, N=76). The primary outcome is the difference in knee pain assessed by WOMAC (Western Ontario and McMaster Universities Arthritis Index) between the CL-Deb and CL-Obs groups at 1-year after surgery. Secondary outcomes include 1-year differences in additional measures of knee pain, function, symptoms, activity, and quality of life assessed by the WOMAC, KOOS (Knee Injury and Osteoarthritis Outcome Score), visual analog pain scale, and physical exam; as well as general health assessed with the SF-36 (Short-form Health Survey). Increased intraoperative costs associated with the addition of chondral debridement will also be assessed. This study will add to the scant literature regarding management of chondral lesions in patients undergoing meniscectomy and might provide treatment guidance for clinicians and their patients. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. A Phase III, Multicenter, Parallel-Design Clinical Trial to Compare the Efficacy and Safety of 5% Minoxidil Foam Versus Vehicle in Women With Female Pattern Hair Loss.

    Science.gov (United States)

    Bergfeld, Wilma; Washenik, Ken; Callender, Valerie; Zhang, Paul; Quiza, Carlos; Doshi, Uday; Blume-Peytavi, Ulrike

    2016-07-01

    BACKGROUND Female pattern hair loss (FPHL) is a common hair disorder that affects millions of women. A new 5% minoxidil topical foam (MTF) formulation, which does not contain propylene glycol, has been developed. To compare the efficacy and safety of once-daily 5% MTF with vehicle foam for the treatment of FPHL. This was a Phase III, randomized, double-blind, vehicle-controlled, parallel-group, international multicenter trial (17 sites) in women aged at least 18 years with FPHL (grade D3 to D6 on the Savin Density Scale), treated once daily with 5% MTF or vehicle foam for 24 weeks. The co-primary efficacy endpoints were the change from baseline at week 24 in target area hair count (TAHC) and subject assessment of scalp coverage. Also evaluated were TAHC at week 12, expert panel review of hair regrowth at week 24, and change from baseline in total unit area density (TUAD, sum of hair diameters/cm2) at weeks 12 and 24. A total of 404 women were enrolled. At 12 and 24 weeks, 5% MTF treatment resulted in regrowth of 10.9 hairs/cm2 and 9.1 hairs/cm2 more than vehicle foam, respectively (both P<.0001). Improved scalp coverage at week 24 was observed by both subject self-assessment (0.69-point improvement over vehicle foam; P<.0001) and expert panel review (0.36-point improvement over the vehicle foam; P<.0001). TUAD increased by 658 μm/cm2 and 644 μm/cm2 more with 5% MTF than with vehicle foam at weeks 12 and 24, respectively (both P<.0001). MTF was well tolerated. A low incidence of scalp irritation and facial hypertrichosis was observed, with no clinically significant differences between groups. Five percent MTF once daily for 24 weeks was well tolerated and promoted hair regrowth in women with FPHL, resulting in improved scalp coverage and increased hair density compared with vehicle foam. ClinicalTrials.gov identifier: nCT01226459J Drugs Dermatol. 2016;15(7):874-881.

  10. Comparative evaluation of pressure generated on a simulated maxillary oral analog by impression materials in custom trays of different spacer designs: An in vitro study.

    Science.gov (United States)

    Chopra, Sakshi; Gupta, Narendra Kumar; Tandan, Amrit; Dwivedi, Ravi; Gupta, Swati; Agarwal, Garima

    2016-01-01

    Literature reveals that masticatory load on denture bearing tissues through complete dentures should be maximum on primary stress bearing areas and least on relief area in accordance with the histology of underlying tissues. A study to validate the existing beliefs was planned to compare the pressure on mucosa using selective pressure technique and minimal pressure technique, with the incorporation of two different impression materials utilizing the pressure sensors during secondary impression procedure. The study was performed using a maxillary analog. Three pressure sensors were imbedded in the oral analog, one in the mid palatine area and the other two in the right and left ridge crest. Custom trays of two different configurations were fabricated. The two impression materials tested were light body and zinc oxide eugenol. A total of 40 impressions were made. A constant weight of 1 kg was placed, and the pressure was recorded as initial and end pressures. A significant difference in the pressure produced using different impression materials was found (P materials. The presence of relief did affect the magnitude of pressure at various locations. All impression materials produced pressure during maxillary edentulous impression making. Tray modification is an important factor in changing the amount of pressure produced. The impression materials used also had a significant role to play on the pressures acting on the tissues during impression procedure. Light body VPS impression material may be recommended to achieve minimal pressure on the denture bearing tissues in both selective as well as minimal pressure techniques.

  11. Design of asymmetric particles containing a charged interior and a neutral surface charge: comparative study on in vivo circulation of polyelectrolyte microgels.

    Science.gov (United States)

    Chen, Kai; Xu, Jing; Luft, J Christopher; Tian, Shaomin; Raval, Jay S; DeSimone, Joseph M

    2014-07-16

    Lowering the modulus of hydrogel particles could enable them to bypass in vivo physical barriers that would otherwise filter particles with similar size but higher modulus. Incorporation of electrolyte moieties into the polymer network of hydrogel particles to increase the swelling ratio is a straightforward and quite efficient way to decrease the modulus. In addition, charged groups in hydrogel particles can also help secure cargoes. However, the distribution of charged groups on the surface of a particle can accelerate the clearance of particles. Herein, we developed a method to synthesize highly swollen microgels of precise size with near-neutral surface charge while retaining interior charged groups. A strategy was employed to enable a particle to be highly cross-linked with very small mesh size, and subsequently PEGylated to quench the exterior amines only without affecting the internal amines. Acidic degradation of the cross-linker allows for swelling of the particles to microgels with a desired size and deformability. The microgels fabricated demonstrated extended circulation in vivo compared to their counterparts with a charged surface, and could potentially be utilized in in vivo applications including as oxygen carriers or nucleic acid scavengers.

  12. Comparative evaluation of pressure generated on a simulated maxillary oral analog by impression materials in custom trays of different spacer designs: An in vitro study

    Directory of Open Access Journals (Sweden)

    Sakshi Chopra

    2016-01-01

    Full Text Available Introduction: Literature reveals that masticatory load on denture bearing tissues through complete dentures should be maximum on primary stress bearing areas and least on relief area in accordance with the histology of underlying tissues. A study to validate the existing beliefs was planned to compare the pressure on mucosa using selective pressure technique and minimal pressure technique, with the incorporation of two different impression materials utilizing the pressure sensors during secondary impression procedure. Materials and Methods: The study was performed using a maxillary analog. Three pressure sensors were imbedded in the oral analog, one in the mid palatine area and the other two in the right and left ridge crest. Custom trays of two different configurations were fabricated. The two impression materials tested were light body and zinc oxide eugenol. A total of 40 impressions were made. A constant weight of 1 kg was placed, and the pressure was recorded as initial and end pressures. Results: A significant difference in the pressure produced using different impression materials was found (P < 0.001. Light body vinyl polysiloxane produced significantly lesser pressure than zinc oxide eugenol impression materials. The presence of relief did affect the magnitude of pressure at various locations. Conclusion: All impression materials produced pressure during maxillary edentulous impression making. Tray modification is an important factor in changing the amount of pressure produced. The impression materials used also had a significant role to play on the pressures acting on the tissues during impression procedure. Clinical Implication: Light body VPS impression material may be recommended to achieve minimal pressure on the denture bearing tissues in both selective as well as minimal pressure techniques.

  13. Comparative Packaging Study

    Science.gov (United States)

    Perchonok, Michele; Antonini, David

    2008-01-01

    This viewgraph presentation describes a comparative packaging study for use on long duration space missions. The topics include: 1) Purpose; 2) Deliverables; 3) Food Sample Selection; 4) Experimental Design Matrix; 5) Permeation Rate Comparison; and 6) Packaging Material Information.

  14. Hospital Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — Hospital Compare has information about the quality of care at over 4,000 Medicare-certified hospitals across the country. You can use Hospital Compare to find...

  15. Research Design

    DEFF Research Database (Denmark)

    2017-01-01

    Gunnar Scott Reinbacher (editor) Antology.  Research Design : Validation in Social Sciences. Gunnar Scott Reinbacher: Introduction. Research design and validity. 15p Ole Riis: Creative Research design. 16 p Lennart Nørreklit: Validity in Research Design. 24p Gitte Sommer Harrits: Praxeological...... knowledge: An integrated strategy for combining "explaining" and "understanding". 22p Heidi Houlberg Salomonsen & Viola Burau: Comparative research designs. 40p Rasmus Antoft & Heidi Houlberg Salomonsen: Studying organizations by a Pragmatic Research Design: the case of qualitative case study  designs. 31p...... Kenneth Mølbjerg Jørgensen: Research as storrytelling: constructing reflexive research practice. 21p Lars Ole Bonde: Reflections on the relationship between research questions, design and methods in the research project "Receptive music therapy with female cancer patients in rehabilitation. 35p Gunnar...

  16. Development of a computer-aided design system for comparative medical animal experiments%比较医学动物实验计算机辅助设计系统的研发

    Institute of Scientific and Technical Information of China (English)

    胡樱; 杨斐; 俞伊军; 高诚

    2011-01-01

    Objective To develop an application software for researchers to design comparative medical animal experiments as well as to learn the designing process independently. Methods The technical information of comparative medical animal researches were screened according to the “science, ethic, economic” principle of laboratory animal usage. The candidate data were analyzed and organized on the basis of relational database schema theory. The framework was designed and the modules were set up refered to the rules and features of comparative medical animal experiment process.The whole program was developed in an user-oriented way by using C + + and MFC library. Result Five modules, including model selecting module, laboratory animal module, environment and condition module, laboratory process module and program output module were established along with the related information database, and the test of whole software was conducted. Conclusions The CAD system for comparative medical animal experiment developed in this study is effective and easy to use in designing animal experiment and self-learning of the design process based on PC.%目的 开发一款辅助研究者设计比较医学动物实验方案和学习实验设计的应用软件.方法 根据实验动物应用的"科学、伦理、经济"原则筛选比较医学动物实验技术资料,运用关系数据库架构原理分析和组织入选数据,通过解析比较医学动物实验规律和特点设计程序框架和模块,采用C++语言、MFC库进行面向用户的程序设计.结果 建立了程序相关资源库和模型选择、实验动物、环境条件、实验步骤、方案输出5个功能模块,并完成整个软件测试.结论 研发成功比较医学动物实验计算机辅助设计系统,该系统能够基于微型计算机为用户提供有效、易用的动物实验辅助设计和自助学习功能.

  17. Slat cove filler design for noise reduction based on artificial neural network%基于人工神经网络的缝翼凹槽填充降噪设计

    Institute of Scientific and Technical Information of China (English)

    陶俊; 孙刚; 徐康乐

    2015-01-01

    Airframe noise becomes one of the dominant noise sources during landing and tak-ing off phases of a civil aircraft because that jet engine noise is decreased obviously in recent years.High lift device noise is the main source of airframe noise,decreasing high lift device noise makes a significant contribution to the overall noise reduction for a civil aircraft.Slat cove filler (SCF),as a type of slat noise reduction method,may decrease the aerodynamic performances, such as the maximum lift coefficient and the stall angle.To this situation,a database of SCF is built for a multi-element airfoil,and one of the SCFs in the database is selected as the reference configuration,20 optimized configurations are generated through confidence coefficient reason-ing.Aerodynamic performance of each optimized configuration is predicted by a back propagation (BP)artificial neural network,and the one with the best aerodynamic performance is selected as the design configuration for verifying computation,steady Navier-Stokes simulations are executed to compare aerodynamic performances of the design configuration with that of the baseline config-uration.A hybrid method,combining CFD with acoustic analogy,is applied to compare the acoustic performances of the design configuration with that of the baseline configuration.The re-sults indicate that the noises are reduced significantly at the given observation points by adding the designed SCF,while the aerodynamic performances have been maintained.%缝翼凹槽填充技术作为一种缝翼降噪方法,有可能会造成气动性能的损失,如最大升力系数和失速迎角的减小。基于这种情况,针对某多段翼型建立了缝翼凹槽填充构型的数据库,挑选出参考构型,利用置信度推理确定了优化方向,生成了20个优化构型;采用 back propagation(BP)人工神经网络快速预测各优化构型的气动性能,选择其中气动性能最好的构型作为设计构型进

  18. Parametric Equations for Estimating Aircraft Airframe Costs

    Science.gov (United States)

    1976-02-01

    prototype program for the first few aircraft is substantially lower because many costs are deferred until a decision to produce for inventory is made...overhead rates. It is necessary to begin with labor hours and convert tbam into dollars. That conversion can result in a serious misstatement of...general and administrative expense (G&A), miscellaneous direct charges (overtime premium, travel, per diem, miscellaneous taxes , etc.), and, in the

  19. Cost Functions for Airframe Production Programs.

    Science.gov (United States)

    1982-07-01

    VIII. RESULTS AND AIRFORCE APPLICATIONS. ........... 164 Introduction Understanding Production Scheduling Program Management and Monitoring Cost...Program Management and Monitoring In addition to contributing to our general understanding of production scheduling, the revised model can be used for...202 38. Womer, N. K. "Learning Curves, Production Rate, and Program Costs." Management Science, Vol. XXV (April, 1979), 312-19. 39. Warer , N. K

  20. Multi-Layered Integrated Airframe System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has a need to develop higher performance ablative thermal protection systems (TPS) than is currently available for future exploration of our solar system's...

  1. A Critique of Aircraft Airframe Cost Models.

    Science.gov (United States)

    1977-09-01

    rframes Aircraft Cost Analysis 2C *3Si PACT [’Cor.rinu* an r+vrmm »lam ti omc +mmmfy mr.J tffonUtf t>f Met.* riutnfcor) see reverse side...numbers, however, the ASD Cost Escalation Re- ft port 110-C would give a factor of 1.44.) 6 Historiaal and Forecasted Aeronautical Cost Indices

  2. Multi-Layered Integrated Airframe System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposed Phase II program builds on the Phase I effort addressing NASA's future mission requirements by: 1) developing higher performing TPS materials capable...

  3. Airframe noise measurements by acoustic imaging

    Science.gov (United States)

    Kendall, J. M.

    1977-01-01

    Studies of the noise produced by flow past wind tunnel models are presented. The central objective of these is to find the specific locations within a flow which are noisy, and to identify the fluid dynamic processes responsible, with the expectation that noise reduction principles will be discovered. The models tested are mostly simple shapes which result in types of flow that are similar to those occurring on, for example, aircraft landing gear and wheel cavities. A model landing gear and a flap were also tested. Turbulence has been intentionally induced as appropriate in order to simulate full-scale effects more closely. The principal technique involves use of a highly directional microphone system which is scanned about the flow field to be analyzed. The data so acquired are presented as a pictorial image of the noise source distribution. An important finding is that the noise production is highly variable within a flow field and that sources can be attributed to various fluid dynamic features of the flow. Flow separation was not noisy, but separation closure usually was.

  4. Physician Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — Physician Compare, which meets Affordable Care Act of 2010 requirements, helps you search for and select physicians and other healthcare professionals enrolled in...

  5. Re-Design and Beat Testing of the Man-Machine Integration Design and Analysis System: MIDAS

    Science.gov (United States)

    Shively, R. Jay; Rutkowski, Michael (Technical Monitor)

    1999-01-01

    The Man-machine Design and Analysis System (MIDAS) is a human factors design and analysis system that combines human cognitive models with 3D CAD models and rapid prototyping and simulation techniques. MIDAS allows designers to ask 'what if' types of questions early in concept exploration and development prior to actual hardware development. The system outputs predictions of operator workload, situational awareness and system performance as well as graphical visualization of the cockpit designs interacting with models of the human in a mission scenario. Recently, MIDAS was re-designed to enhance functionality and usability. The goals driving the redesign include more efficient processing, GUI interface, advances in the memory structures, implementation of external vision models and audition. These changes were detailed in an earlier paper. Two Beta test sites with diverse applications have been chosen. One Beta test site is investigating the development of a new airframe and its interaction with the air traffic management system. The second Beta test effort will investigate 3D auditory cueing in conjunction with traditional visual cueing strategies including panel-mounted and heads-up displays. The progress and lessons learned on each of these projects will be discussed.

  6. Comparative Advantage

    DEFF Research Database (Denmark)

    Zhang, Jie; Jensen, Camilla

    2007-01-01

    that are typically explained from the supply-side variables, the comparative advantage of the exporting countries. A simple model is proposed and tested. The results render strong support for the relevance of supply-side factors such as natural endowments, technology, and infrastructure in explaining international...

  7. Comparative hemorheology

    OpenAIRE

    Başkurt, Oğuz K.; Meiselman, Herbert J.

    2013-01-01

    Comparative data on blood composition and blood flow properties indicate different levels of interspecies variation for several parameters. Hematocrit and hemoglobin levels have relatively low variability among mammals, while mean cell volume and red blood cell (RBC) count are more variable. There is also a difference of variability between high and low shear rate blood viscosity in mammals, with low shear rate viscosity having a higher degree of interspecies variation. This observation paral...

  8. 非加劲钢板剪力墙国内外设计方法比较分析%Comparative study on design methods for unstiffened steel plate shear wall in different codes

    Institute of Scientific and Technical Information of China (English)

    徐建; 石永久; 戴国欣; 王元清; 杨蔚彪

    2012-01-01

    钢板剪力墙已在高层建筑中开始得到应用,国外已有钢板剪力墙的设计规范,但中国对钢板剪力墙的设计方法规定还比较保守,其设计准则仍基于厚钢板墙的设计理念.本文根据美国规范AISC-341 2005、加拿大规范CAN/CSA S16-01以及中国的高层建筑规程对非加劲钢板剪力墙的设计过程进行了对比,对墙板的抗剪承载力,尤其是对薄板屈曲后形成拉力场的性能进行了相关实例的计算,并对设计结果进行了比较.结果表明,美国和加拿大规范在高厚比较大时,能较准确反映墙板的抗剪承载力;中国规范只是在高厚比较小时能准确计算其抗剪承载力,高厚比较大时,既不准确,也不经济.%Steel Plate Shear Wall( short for SPSW) structures are beginning being used in structural application. Until now,there have been several design codes for unstiffened SPSW at abroad. However,such a specification on SPSW been prescribed in China is more conservative,whose design criteria is still based on the concept of thick SPSW design. According to American (AISC -341 2005) , Canadian (CAN/CSA S16 -01) and Chinese high-rise building regulations, the unstiffened SPSW was contrasted in the design process. The related example in calculations was given and the results of the design were compared. The item to be calculated here is the shear resistance, especially the postbuckling strength after the thin wall buckling and forming the tension field. The results show that the correlative provision in America and Canada can more accurately reflect the shear resistance of the wall with large height-thickness ratio. However,the provision in China can only accurately reflect it with small height-thickness ratio, which is not accurate or economical for thin plate wall.

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

    Directory of Open Access Journals (Sweden)

    Lene van der Merwe

    2012-11-01

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

  10. Design, fabrication and test of liquid metal heat-pipe sandwich panels

    Science.gov (United States)

    Basiulis, A.; Camarda, C. J.

    1983-01-01

    Integral heat-pipe sandwich panels, which synergistically combine the thermal efficiency of heat pipes and the structural efficiency of honeycomb sandwich panel construction, were fabricated and tested. The designs utilize two different wickable honeycomb cores, facesheets with screen mesh sintered to the internal surfaces, and potassium or sodium as the working fluid. Panels were tested by radiant heating, and the results indicate successful heat pipe operation at temperatures of approximately 922K (1200F). These panels, in addition to solving potential thermal stress problems in an Airframe-Integrated Scramjet Engine, have potential applications as cold plates for electronic component cooling, as radiators for space platforms, and as low distortion, large area structures.

  11. COMPARATIVE RESEARCH REGARDING THE DESIGN AND THE DEVELOPMENT OF THE G CODE PROGRAMMING LANGUAGE BETWEEN CASE R290-02IS AND THE CLASSIC VERSION, CONSTITUENTS OF THE GARLAND PRODUCT C3G 1200, 1400, 1600

    Directory of Open Access Journals (Sweden)

    Valeria Victoria IOVANOV

    2014-05-01

    Full Text Available A CNC machine makes use of mathematics and various coordinate systems to understand and process the information it receives to determine what to move where and how fast . The most important function of any CNC machine is precise and rigorous control of the movement. All CNC equipment have two or more directions of motion, called axes. CNC machines are driven by computer controlled servo motors and generally guided by a stored program, the type of movement (fast , linear, circular , the moving axes, the distances of movement and the speed of movement ( processing being programmable for most CNC machines . This paper proposes the design and implementation of a G code programming language for the reference point Case R290 - 02IS the short version compared to the classical part of the garland product C3G 1200,1400,1600 , reference points used in all fields that use conveyors .

  12. A comparative analysis on Business English curriculum design of the three universities in China%国内三所高校商务英语专业课程设置比较分析

    Institute of Scientific and Technical Information of China (English)

    李静

    2011-01-01

    文章对国内三所高校商务英语专业的课程设置进行了比较分析,并提出以下观点:普通高校商务英语专业没有必要开设二外课程;适当降低基础英语课程的比重;提高外语专业学生思维能力和创新能力。%This paper makes a comparative analysis on Business English curriculum design of the three universities in China and proposes suggestions as follows: There is no need for Business English majors to learn the second foreign language;It is necessary to reduce the proportion of basic English courses;It is urgent to improve the intellectual and creative abilities of foreign language majors.

  13. Comparative techno-economic analysis and process design for indirect liquefaction pathways to distillate-range fuels via biomass-derived oxygenated intermediates upgrading: Liquid Transportation Fuel Production via Biomass-derived Oxygenated Intermediates Upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Eric C. D. [National Renewable Energy Laboratory, Golden CO USA; Snowden-Swan, Lesley J. [Pacific Northwest National Laboratory, Richland WA USA; Talmadge, Michael [National Renewable Energy Laboratory, Golden CO USA; Dutta, Abhijit [National Renewable Energy Laboratory, Golden CO USA; Jones, Susanne [Pacific Northwest National Laboratory, Richland WA USA; Ramasamy, Karthikeyan K. [Pacific Northwest National Laboratory, Richland WA USA; Gray, Michel [Pacific Northwest National Laboratory, Richland WA USA; Dagle, Robert [Pacific Northwest National Laboratory, Richland WA USA; Padmaperuma, Asanga [Pacific Northwest National Laboratory, Richland WA USA; Gerber, Mark [Pacific Northwest National Laboratory, Richland WA USA; Sahir, Asad H. [National Renewable Energy Laboratory, Golden CO USA; Tao, Ling [National Renewable Energy Laboratory, Golden CO USA; Zhang, Yanan [National Renewable Energy Laboratory, Golden CO USA

    2016-09-27

    This paper presents a comparative techno-economic analysis (TEA) of five conversion pathways from biomass to gasoline-, jet-, and diesel-range hydrocarbons via indirect liquefaction with a specific focus on pathways utilizing oxygenated intermediates. The four emerging pathways of interest are compared with one conventional pathway (Fischer-Tropsch) for the production of the hydrocarbon blendstocks. The processing steps of the four emerging pathways include biomass-to-syngas via indirect gasification, syngas clean-up, conversion of syngas to alcohols/oxygenates followed by conversion of alcohols/oxygenates to hydrocarbon blendstocks via dehydration, oligomerization, and hydrogenation. Conversion of biomass-derived syngas to oxygenated intermediates occurs via three different pathways, producing: (i) mixed alcohols over a MoS2 catalyst, (ii) mixed oxygenates (a mixture of C2+ oxygenated compounds, predominantly ethanol, acetic acid, acetaldehyde, ethyl acetate) using an Rh-based catalyst, and (iii) ethanol from syngas fermentation. This is followed by the conversion of oxygenates/alcohols to fuel-range olefins in two approaches: (i) mixed alcohols/ethanol to 1-butanol rich mixture via Guerbet reaction, followed by alcohol dehydration, oligomerization, and hydrogenation, and (ii) mixed oxygenates/ethanol to isobutene rich mixture and followed by oligomerization and hydrogenation. The design features a processing capacity of 2000 tonnes/day (2205 short tons) of dry biomass. The minimum fuel selling prices (MFSPs) for the four developing pathways range from $3.40 to $5.04 per gasoline-gallon equivalent (GGE), in 2011 US dollars. Sensitivity studies show that MFSPs can be improved with co-product credits and are comparable to the commercial Fischer-Tropsch benchmark ($3.58/GGE). Overall, this comparative TEA study documents potential economics for the developmental biofuel pathways via mixed oxygenates.

  14. Comparative techno-economic analysis and process design for indirect liquefaction pathways to distillate-range fuels via biomass-derived oxygenated intermediates upgrading: Liquid Transportation Fuel Production via Biomass-derived Oxygenated Intermediates Upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Eric C. D. [National Renewable Energy Laboratory, Golden CO USA; Snowden-Swan, Lesley J. [Pacific Northwest National Laboratory, Richland WA USA; Talmadge, Michael [National Renewable Energy Laboratory, Golden CO USA; Dutta, Abhijit [National Renewable Energy Laboratory, Golden CO USA; Jones, Susanne [Pacific Northwest National Laboratory, Richland WA USA; Ramasamy, Karthikeyan K. [Pacific Northwest National Laboratory, Richland WA USA; Gray, Michel [Pacific Northwest National Laboratory, Richland WA USA; Dagle, Robert [Pacific Northwest National Laboratory, Richland WA USA; Padmaperuma, Asanga [Pacific Northwest National Laboratory, Richland WA USA; Gerber, Mark [Pacific Northwest National Laboratory, Richland WA USA; Sahir, Asad H. [National Renewable Energy Laboratory, Golden CO USA; Tao, Ling [National Renewable Energy Laboratory, Golden CO USA; Zhang, Yanan [National Renewable Energy Laboratory, Golden CO USA

    2016-09-27

    This paper presents a comparative techno-economic analysis (TEA) of five conversion pathways from biomass to gasoline-, jet-, and diesel-range hydrocarbons via indirect liquefaction with specific focus on pathways utilizing oxygenated intermediates. The four emerging pathways of interest are compared with one conventional pathway (Fischer-Tropsch) for the production of the hydrocarbon blendstocks. The processing steps of the four emerging pathways include: biomass to syngas via indirect gasification, gas cleanup, conversion of syngas to alcohols/oxygenates followed by conversion of alcohols/oxygenates to hydrocarbon blendstocks via dehydration, oligomerization, and hydrogenation. Conversion of biomass-derived syngas to oxygenated intermediates occurs via three different pathways, producing: 1) mixed alcohols over a MoS2 catalyst, 2) mixed oxygenates (a mixture of C2+ oxygenated compounds, predominantly ethanol, acetic acid, acetaldehyde, ethyl acetate) using an Rh-based catalyst, and 3) ethanol from syngas fermentation. This is followed by the conversion of oxygenates/alcohols to fuel-range olefins in two approaches: 1) mixed alcohols/ethanol to 1-butanol rich mixture via Guerbet reaction, followed by alcohol dehydration, oligomerization, and hydrogenation, and 2) mixed oxygenates/ethanol to isobutene rich mixture and followed by oligomerization and hydrogenation. The design features a processing capacity of 2,000 tonnes/day (2,205 short tons) of dry biomass. The minimum fuel selling prices (MFSPs) for the four developing pathways range from $3.40 to $5.04 per gasoline-gallon equivalent (GGE), in 2011 US dollars. Sensitivity studies show that MFSPs can be improved with co-product credits and are comparable to the commercial Fischer-Tropsch benchmark ($3.58/GGE). Overall, this comparative TEA study documents potential economics for the developmental biofuel pathways via mixed oxygenates.

  15. 适用于纹波控制型DC-DC变换器的比较器设计%Design of PWM Comparator for DC-DC Converter Based on Ripple Control

    Institute of Scientific and Technical Information of China (English)

    杨靖; 冯全源

    2014-01-01

    设计一种适用于纹波控制( Output-Ripple-Based Control)的Buck型DC-DC变换器的比较器,根据PSIM搭建的仿真模型,分析主环比较器性能对系统的影响,设计具有三级预放大的高增益,低延时,低失调电压的比较器电路,采用两种温度系数的电流补偿比较器增益,稳定增益,采用0.5μm BiCOMS工艺进行仿真验证,下降沿延时27 ns,增益123 dB,随温度最大增益变化3.2%,失调电压90μV,达到系统要求。%A kind of comparator applicable to Output-Ripple-Based Control DC-DC Converter was put forward. By using PSIM to build simulation model,and analysing the main loop comparator's performance,the influence of the system,a comparator circuit with preamplifier of high gain,low delay,low disorder voltage were designed. The two kinds of temperature coefficient of bias current are using to compensate the comparator's gain,By using 0. 5 μm BiCOMS process to simulation verification,the falling edge delay is 27 ns,gain is 123 dB,the biggest gain 3. 2%with temperature changes,offset voltage 90 μV and they all reach the system requirements.

  16. A Monte Carlo simulation study comparing linear regression, beta regression, variable-dispersion beta regression and fractional logit regression at recovering average difference measures in a two sample design.

    Science.gov (United States)

    Meaney, Christopher; Moineddin, Rahim

    2014-01-24

    In biomedical research, response variables are often encountered which have bounded support on the open unit interval--(0,1). Traditionally, researchers have attempted to estimate covariate effects on these types of response data using linear regression. Alternative modelling strategies may include: beta regression, variable-dispersion beta regression, and fractional logit regression models. This study employs a Monte Carlo simulation design to compare the statistical properties of the linear regression model to that of the more novel beta regression, variable-dispersion beta regression, and fractional logit regression models. In the Monte Carlo experiment we assume a simple two sample design. We assume observations are realizations of independent draws from their respective probability models. The randomly simulated draws from the various probability models are chosen to emulate average proportion/percentage/rate differences of pre-specified magnitudes. Following simulation of the experimental data we estimate average proportion/percentage/rate differences. We compare the estimators in terms of bias, variance, type-1 error and power. Estimates of Monte Carlo error associated with these quantities are provided. If response data are beta distributed with constant dispersion parameters across the two samples, then all models are unbiased and have reasonable type-1 error rates and power profiles. If the response data in the two samples have different dispersion parameters, then the simple beta regression model is biased. When the sample size is small (N0 = N1 = 25) linear regression has superior type-1 error rates compared to the other models. Small sample type-1 error rates can be improved in beta regression models using bias correction/reduction methods. In the power experiments, variable-dispersion beta regression and fractional logit regression models have slightly elevated power compared to linear regression models. Similar results were observed if the

  17. Design Methodology - Design Synthesis

    DEFF Research Database (Denmark)

    Andreasen, Mogens Myrup

    2003-01-01

    ABSTRACT Design Methodology shall be seen as our understanding of how to design; it is an early (emerging late 60ies) and original articulation of teachable and learnable methodics. The insight is based upon two sources: the nature of the designed artefacts and the nature of human designing. Today...... Design Methodology is part of our practice and our knowledge about designing, and it has been strongly supported by the establishing and work of a design research community. The aim of this article is to broaden the reader¿s view of designing and Design Methodology. This is done by sketching...... the development of Design Methodology through time and sketching some important approaches and methods. The development is mainly forced by changing industrial condition, by the growth of IT support for designing, but also by the growth of insight into designing created by design researchers....

  18. Design of a Window-Comparator Oscillator with High Precision and High Stability%一种高精度高稳定性窗口比较式振荡器的设计

    Institute of Scientific and Technical Information of China (English)

    吴蓉; 邹伟

    2013-01-01

    Based on the current mode,a sawtooth wave oscillator which used in DC-DC switching power management chip is designed.This circuit uses a window-comparator architecture and a constant current source charging and discharging to achieve the oscillator circuit of low voltage and low power consumption,and high frequency and high precision.The circuit was simulated with Cadence tool and 0.5 μm CMOS process CSMC.Simulation results show that designed frequency of the oscillator is 1MHz,and the variation of oscillator frequency is 3.57% and 2.55% in the range of 3~-5V and temperature of-40℃ ~80℃.With a high precision and a high stability,the oscillator can be widely used in the design of a DC-DC switch power management chip.%基于电流模式设计了一种应用于DC-DC开关电源管理芯片的锯齿波振荡器.该电路采用窗口比较式结构和恒流源充放电技术,实现了低压低功耗、高频高精度的振荡电路.用Cadence软件和CSMC的0.5μm CMOS工艺进行仿真,结果表明:该电路的振荡频率为1 MH-z,电源电压在3~5 V、温度在-40~80℃变化范围内的频率变化率分别为3.57%和2.55%.该振荡器精度高、稳定性好,可以广泛应用在DC-DC开关电源管理芯片中.

  19. Comparative evaluations.

    Science.gov (United States)

    Bibace, Roger

    2008-03-01

    My response to Engelmann (2008) will be based on several questions that will allow both its author and the general reader to determine whether the assumptions I make as an interpreter of this complex paper are congruent or incongruent with their own interpretations of the text. The interpretations by the writer, by any commentator, and the diverse interpretations of a general audience together with my own interpretations will, I hope, facilitate some fruitful 'comparative evaluations.' I articulate my inferences of the most dense part of the paper, namely the 'concrete immediate Consciousness and the developing absent outside.' My hope is to address Engelmann's question: "Am I in a better disposition to judge modern theories of consciousness?" The last section of my response spells out more personal comments to my all too brief and single encounter with Arno Engelmann. It is there that Arno Engelmann's fascinating statement "I am a citizen of the world" is addressed through its counterparts in my life.

  20. Designing Material Materialising Design

    DEFF Research Database (Denmark)

    Nicholas, Paul

    2013-01-01

    Designing Material Materialising Design documents five projects developed at the Centre for Information Technology and Architecture (CITA) at the Royal Danish Academy of Fine Arts, School of Architecture. These projects explore the idea that new designed materials might require new design methods....... Focusing on fibre reinforced composites, this book sustains an exploration into the design and making of elastically tailored architectural structures that rely on the use of computational design to predict sensitive interdependencies between geometry and behaviour. Developing novel concepts...

  1. COMPARATIVE STUDY ON DESIGN METHODS FOR LOCAL STABILITY OF HIGH STRENGTH STEEL FLEXURAL MEMBERS IN DIFFERENT CODES%高强度钢材受弯构件局部稳定设计方法对比∗

    Institute of Scientific and Technical Information of China (English)

    徐克龙; 石永久; 李一昕

    2016-01-01

    Nowadays, high strength steel has been used in building structures, and researches on high strength steel structures have been increasingly conducted at home and overseas. The steel structure design standards in Europe and United States have involved the design method for high strength steel structures. However, the current code in China does not include such content. The new edition of Code for Design of Steel Structure (GB 50017—201X), which is now under revision, would take the high strength steel Q460 into consideration. By comparing the specifications of local stability of I-section flexural members in American code ANSI/AISC 360 -10, Eurocode BS EN 1993 -1, Japanese code AIJ LSD2010, and Chinese code GB 50017—2003, it showed that the related provisions about design scope and principle, width-to-thickness ratio of plate, post-buckling behavior of web and maximum height-to-thickness ratio of web are variant in different degrees, then, a 4-point loading finite element model of I-section flexural member was established by ANSYS to calculate post-buckling ultimate bearing capacity with different steel grades. The finite element analysis results were compared with the results calculated by the formulas from different standards, which showed that the existing specifications could not be applied to the design of local stability of high strength steel flexural members.%目前,高强度钢材已在建筑结构中得到了推广应用,国内外关于高强度钢材钢结构的研究工作也已逐步开展起来。欧洲和美国的钢结构设计标准已涉及到部分高强度钢材的设计内容,而GB 50017—2003《钢结构设计规范》尚未包含,修订中的新版《钢结构设计规范》计划纳入Q460高强度钢材。通过对比各国设计标准中关于工字形截面受弯构件局部稳定的规定,发现美国标准ANSI/AISC 360-10、欧洲标准BS EN 1993-1、日本标准AIJ LSD2010和中国规范GB 50017—2003在设计范围和

  2. Designing Material Materialising Design

    DEFF Research Database (Denmark)

    Nicholas, Paul

    2013-01-01

    Designing Material Materialising Design documents five projects developed at the Centre for Information Technology and Architecture (CITA) at the Royal Danish Academy of Fine Arts, School of Architecture. These projects explore the idea that new designed materials might require new design methods...

  3. Comparative in vitro metabolism of the 'designer' steroid estra-4,9-diene-3,17-dione between the equine, canine and human: identification of target metabolites for use in sports doping control.

    Science.gov (United States)

    Scarth, James P; Clarke, Adam D; Teale, Philip; Pearce, Clive M

    2010-10-01

    Effective detection of the abuse of androgenic-anabolic steroids in human and animal sports often requires knowledge of the drug's metabolism in order to target appropriate urinary metabolites. 'Designer' steroids are problematic since it is difficult to obtain ethical approval for in vivo metabolism studies due to a lack of a toxicological profile. In this study, the in vitro metabolism of estra-4,9-diene-3,17-dione is reported for the first time. This is also the first study comparing the metabolism of a designer steroid in the three major species subject to sport's doping control; namely the equine, canine and human. In order to allow the retrospective analysis of sample testing data, the use of a high-resolution (HR) accurate-mass Thermo LTQ-Orbitrap LC-MS instrument was employed for metabolite identification of underivatised sample extracts. The full scan HR-LC-MS Orbitrap data was complimented by several further experiments targeted at elucidating more detailed structural information for the most abundant metabolites. These included; HR-LC-MS/MS of the underivatised metabolites, functional group selective chemical derivatisation followed by full scan HR-LC-MS, enzyme inhibition experiments and full scan electron ionization GC-MS analysis of methoxyamine-trimethylsilyl derivatives. The major metabolite detected in all species, and therefore the most suitable candidate for screening of estra-4,9-diene-3,17-dione abuse, was proposed to be an isomer of 17-hydroxy-estra-4,9-dien-3-one. Less significant metabolic pathways in all species included hydroxylation and reduction followed by hydroxylation. Reductive metabolism in the canine was less significant than in the other two species, while the equine was unique in producing a di-reduced metabolite (proposed to be an isomer of estra-4,9-diene-3,17-diol) and also relatively large quantities of d-ring hydroxy and hydroxy-reduced metabolites.

  4. Quality of life of residents with dementia in long-term care settings in the Netherlands and Belgium: design of a longitudinal comparative study in traditional nursing homes and small-scale living facilities

    Directory of Open Access Journals (Sweden)

    Luijkx Katrien G

    2011-05-01

    Full Text Available Abstract Background The increase in the number of people with dementia will lead to greater demand for residential care. Currently, large nursing homes are trying to transform their traditional care for residents with dementia to a more home-like approach, by developing small-scale living facilities. It is often assumed that small-scale living will improve the quality of life of residents with dementia. However, little scientific evidence is currently available to test this. The following research question is addressed in this study: Which (combination of changes in elements affects (different dimensions of the quality of life of elderly residents with dementia in long-term care settings over the course of one year? Methods/design A longitudinal comparative study in traditional and small-scale long-term care settings, which follows a quasi-experimental design, will be carried out in Belgium and the Netherlands. To answer the research question, a model has been developed which incorporates relevant elements influencing quality of life in long-term care settings. Validated instruments will be used to evaluate the role of these elements, divided into environmental characteristics (country, type of ward, group size and nursing staff; basic personal characteristics (age, sex, cognitive decline, weight and activities of daily living; behavioural characteristics (behavioural problems and depression; behavioural interventions (use of restraints and use of psychotropic medication; and social interaction (social engagement and visiting frequency of relatives. The main outcome measure for residents in the model is quality of life. Data are collected at baseline, after six and twelve months, from residents living in either small-scale or traditional care settings. Discussion The results of this study will provide an insight into the determinants of quality of life for people with dementia living in traditional and small-scale long-term care settings in

  5. Rationale and design of the Exercise Intensity Trial (EXCITE: A randomized trial comparing the effects of moderate versus moderate to high-intensity aerobic training in women with operable breast cancer

    Directory of Open Access Journals (Sweden)

    Herndon James E

    2010-10-01

    Full Text Available Abstract Background The Exercise Intensity Trial (EXcITe is a randomized trial to compare the efficacy of supervised moderate-intensity aerobic training to moderate to high-intensity aerobic training, relative to attention control, on aerobic capacity, physiologic mechanisms, patient-reported outcomes, and biomarkers in women with operable breast cancer following the completion of definitive adjuvant therapy. Methods/Design Using a single-center, randomized design, 174 postmenopausal women (58 patients/study arm with histologically confirmed, operable breast cancer presenting to Duke University Medical Center (DUMC will be enrolled in this trial following completion of primary therapy (including surgery, radiation therapy, and chemotherapy. After baseline assessments, eligible participants will be randomized to one of two supervised aerobic training interventions (moderate-intensity or moderate/high-intensity aerobic training or an attention-control group (progressive stretching. The aerobic training interventions will include 150 mins.wk-1 of supervised treadmill walking per week at an intensity of 60%-70% (moderate-intensity or 60% to 100% (moderate to high-intensity of the individually determined peak oxygen consumption (VO2peak between 20-45 minutes/session for 16 weeks. The progressive stretching program will be consistent with the exercise interventions in terms of program length (16 weeks, social interaction (participants will receive one-on-one instruction, and duration (20-45 mins/session. The primary study endpoint is VO2peak, as measured by an incremental cardiopulmonary exercise test. Secondary endpoints include physiologic determinants that govern VO2peak, patient-reported outcomes, and biomarkers associated with breast cancer recurrence/mortality. All endpoints will be assessed at baseline and after the intervention (16 weeks. Discussion EXCITE is designed to investigate the intensity of aerobic training required to induce optimal

  6. Designing parks : an examination of contemporary approaches to design in landscape architecture, based on a comparative design analysis of entries for the Concours International: Parc de la Villette, Paris, 1982-3 = Park ontwerpen : een beschouwing over hedendaagse ontwerpopvattingen in de parkarchitectuur, behandeld aan de hand van een vergelijkende ontwerpanalyse van inzendingen voor het ...

    NARCIS (Netherlands)

    Baljon, L.

    1992-01-01

    PARK DESIGNS Parks are planted places in which vegetation, earth, water, and constructions are cultivated in such a way through composition that they acquire a meaning beyond the significance of the single plant. Without imagination a park is a mere dry décor for people who come and go; a m

  7. The Beetle comparator implementation

    CERN Document Server

    Van Beuzekom, M G

    2003-01-01

    Measurements of the comparator thresholds on a Beetle 1.1 chip show large variations. The width of the threshold distribution is several tenths of a MIP signal for a 300 µm silicon detector, which is more than can be corrected for by individual threshold settings. Monte Carlo simulations of the production-process parameters have been performed to track the cause of this large offset spread. The main cause of the offset variation is the spread in the threshold voltage of the MOSFETs. Since this cannot easily be solved by a change in the design of the comparator as such, the solution is to increase the range of the individual threshold settings while maintaining the same resolution. This implies an increase in the number of bits for the individual thresholds. The note describes measurements and simulations for the Beetle versions 1.1 and 1.2, and the changes in the design for the Beetle 1.3.

  8. Detailed design of a lattice composite fuselage structure by a mixed optimization method

    Science.gov (United States)

    Liu, D.; Lohse-Busch, H.; Toropov, V.; Hühne, C.; Armani, U.

    2016-10-01

    In this article, a procedure for designing a lattice fuselage barrel is developed. It comprises three stages: first, topology optimization of an aircraft fuselage barrel is performed with respect to weight and structural performance to obtain the conceptual design. The interpretation of the optimal result is given to demonstrate the development of this new lattice airframe concept for the fuselage barrel. Subsequently, parametric optimization of the lattice aircraft fuselage barrel is carried out using genetic algorithms on metamodels generated with genetic programming from a 101-point optimal Latin hypercube design of experiments. The optimal design is achieved in terms of weight savings subject to stability, global stiffness and strain requirements, and then verified by the fine mesh finite element simulation of the lattice fuselage barrel. Finally, a practical design of the composite skin complying with the aircraft industry lay-up rules is presented. It is concluded that the mixed optimization method, combining topology optimization with the global metamodel-based approach, allows the problem to be solved with sufficient accuracy and provides the designers with a wealth of information on the structural behaviour of the novel anisogrid composite fuselage design.

  9. How Expert Designers Design

    NARCIS (Netherlands)

    C. Carr; Dr. Peter Sloep; P. Kirschner; J. van Merrienboer

    2003-01-01

    This paper discusses two studies - the one in a business context, the other in a university context - carried out with expert educational designers. The studies aimed to determine the priorities experts claim to employ when designing competence-based learning environments. Designers in both contexts

  10. Comparative Study of GEK ( Gradient?Enhanced Kriging) and Kriging When Applied to Design Optimization%梯度增强的Kriging模型与Kriging模型在优化设计中的比较研究

    Institute of Scientific and Technical Information of China (English)

    刘俊; 宋文萍; 韩忠华; 王乐

    2015-01-01

    In many engineering optimization design problems, the objective function ( s) as well as the constraint function ( s ) are really computationally expensive. To reduce the computational time and shorten the design process, surrogate models are often used. In recent years, to further improve the design efficiency, a variety of new surrogate models are developed as extensions from the traditional models and verified to have higher efficiency for prediction, such as the variable?fidelity models and gradient?enhanced models. To investigate the design optimization efficiency when these new surrogate models are used, a universal surrogate?based optimization frame?work, which combines the surrogate models, multi sample point infill criteria, and multi?type traditional optimiza?tion algorithms, is developed first. Then, several typical analytical optimization problems are employed to compare the optimization efficiency when the widely used Kriging and a newly developed GEK are used respectively. The re?sults and their analysis show preliminarily that, for most cases, GEK get better optimal solution with the same com?putational expense. Finally, an engineering problem, the airfoil inverse design is introduced for comparison; the gradients of the objective functions used to construct the GEK are obtained by the efficient adjoint method. The re?sults and their analysis also show preliminarily that, when using the GEK, not only the efficiency, but also the opti?mal solution can be improved as compared with the Kriging model.%在许多工程优化设计问题中,由于需要采用费时的数值模拟方法获得目标函数和约束函数值,出现了优化时间过长、优化难度大的问题. 为了提高设计效率,缩短优化设计周期,代理模型方法受到人们的欢迎. 近些年来,为了进一步提高设计效率,人们在传统代理模型基础上又发展了一些更高效、预测精度更高的新型代理模型,如变可信度模型、

  11. Comparative Study and Improvement Design on Aerodynamic Charac-teristics of Typical Reentry Capsules%典型再入返回器气动特性对比与改进研究

    Institute of Scientific and Technical Information of China (English)

    詹慧玲; 陈冰雁; 刘周; 周伟江

    2013-01-01

    返回器气动特性研究对宇宙飞船的研制起着先导和制约作用。文章对 Apollo、CEV 和类Soyuz这3种典型的轴对称钝头体再入返回器气动布局进行了气动特性的对比分析,发现与Apollo、CEV相比,类Soyuz外形的升阻比偏小,无法满足以第二宇宙速度载人空间再入返回的要求。在此基础上研究了几何参数(包括倒锥角和球冠半径)变化对类Soyuz外形返回器气动性能的影响规律,从中得到类Soyuz 外形的改进方向,提出了一种以类 Soyuz 外形为基础的改进设计外形,并对该外形的升阻特性、稳定性和配平特性等相关气动特性进行了分析。研究表明通过对几何外形参数的调整优化来提高类Soyuz外形的升阻比,从而达到以第二宇宙速度再入返回的升阻比要求,这样的技术途径是可行的。%The aerodynamic characteristics investigation of reentry capsule plays an important role in the design of spacecraft. Comparative analysis of the aerodynamics between Soyuz and Apollo/CEV configurations is accomplished in this paper. The lift-to-drag ratio of Soyuz which is lower than that of Apollo/CEV cannot meet the requirement of manned capsule reentry at second cosmic velocity from space. The influence of geo-metric parameters, including after-body angle and heat shield radius, on the aerodynamic characteristics of Soyuz configuration is analyzed. And a modified configuration is suggested on the basis of Soyuz. The aerody-namic characteristics of the modified configuration are analyzed, including lift-to-drag ratio, stability, and trim characteristics. The results show that adjusting and optimizing the geometric parameters of Soyuz re-entry capsule is a feasible way for designing a capsule configuration to meet the high lift-to-drag ratio requirement of manned capsule reentry at second cosmic velocity.

  12. The ACTonHEART study: rationale and design of a randomized controlled clinical trial comparing a brief intervention based on Acceptance and Commitment Therapy to usual secondary prevention care of coronary heart disease.

    Science.gov (United States)

    Spatola, Chiara A M; Manzoni, Gian Mauro; Castelnuovo, Gianluca; Malfatto, Gabriella; Facchini, Mario; Goodwin, Christina L; Baruffi, Matteo; Molinari, Enrico

    2014-02-19

    Modifiable risk factors, including life-style habits and psychological variables, have been increasingly demonstrated to have an important role in influencing morbidity and mortality in cardiovascular patients, and to account for approximately 90% of the population risk for cardiac events.Acceptance and Commitment Therapy (ACT) has shown effectiveness in promoting healthy behaviors, and improving psychological well-being in patients with chronic physical conditions. Moreover, a first application of an acceptance-based program in cardiac patients has revealed high treatment satisfaction and initial evidences of effectiveness in increasing heart-healthy behaviour. However, no clinical trial to date has evaluated the efficacy of an acceptance-based program for the modification of cardiovascular risk factors and the improvement of psychological well-being, compared to usual secondary prevention care. Approximately 168 patients will be recruited from an outpatient cardiac rehabilitation unit and randomly assigned to receive usual care or usual care + a brief ACT-based intervention. The ACT group will be administered five group therapy sessions integrating educational topics on heart-healthy behaviours with acceptance and mindfulness skills. Participants will be assessed at baseline, six weeks later (post treatment for the ACT condition), at six and twelve months follow-up.A partially-nested design will be used to balance effects due to clustering of participants into small therapy groups. Primary outcome measures will include biological indicators of cardiovascular risk and self-reported psychological well-being. Treatment effects will be tested via multilevel modeling after which the mediational role of psychological flexibility will be evaluated. The ACTonHEART study is the first randomized clinical trial designed to evaluate the efficacy of a brief group-administered, ACT-based program to promote health behavior change and psychological well-being among cardiac

  13. SU-D-201-07: Exploring the Utility of 4D FDG-PET/CT Scans in Design of Radiation Therapy Planning Compared with 3D PET/CT: A Prospective Study

    Energy Technology Data Exchange (ETDEWEB)

    Ma, C; Yin, Y [Shandong Tumor Hospital, Jinan, Shandong Provice (China)

    2015-06-15

    Purpose: A method using four-dimensional(4D) PET/CT in design of radiation treatment planning was proposed and the target volume and radiation dose distribution changes relative to standard three-dimensional (3D) PET/CT were examined. Methods: A target deformable registration method was used by which the whole patient’s respiration process was considered and the effect of respiration motion was minimized when designing radiotherapy planning. The gross tumor volume of a non-small-cell lung cancer was contoured on the 4D FDG-PET/CT and 3D PET/CT scans by use of two different techniques: manual contouring by an experienced radiation oncologist using a predetermined protocol; another technique using a constant threshold of standardized uptake value (SUV) greater than 2.5. The target volume and radiotherapy dose distribution between VOL3D and VOL4D were analyzed. Results: For all phases, the average automatic and manually GTV volume was 18.61 cm3 (range, 16.39–22.03 cm3) and 31.29 cm3 (range, 30.11–35.55 cm3), respectively. The automatic and manually volume of merged IGTV were 27.82 cm3 and 49.37 cm3, respectively. For the manual contour, compared to 3D plan the mean dose for the left, right, and total lung of 4D plan have an average decrease 21.55%, 15.17% and 15.86%, respectively. The maximum dose of spinal cord has an average decrease 2.35%. For the automatic contour, the mean dose for the left, right, and total lung have an average decrease 23.48%, 16.84% and 17.44%, respectively. The maximum dose of spinal cord has an average decrease 1.68%. Conclusion: In comparison to 3D PET/CT, 4D PET/CT may better define the extent of moving tumors and reduce the contouring tumor volume thereby optimize radiation treatment planning for lung tumors.

  14. Randomized adjuvant study comparing two schemes of 5-fluorouracil and leucovorin in stage B2 and C colon adenocarcinoma: study design and preliminary safety results. Groupe d'Etude et de Recherche Clinique en Oncologie Radiotherapies.

    Science.gov (United States)

    André, T; Colin, P; Louvet, C; Gamelin, E; Bouche, O; Achille, E; Colbert, N; Boaziz, C; Piedbois, P; Tubiana-Mathieu, N; Boutan-Laroze, A; Flesch, M; Billiau, V; Buyse, M; Gramont, A

    2001-02-01

    The aim of this randomized open-label study was to compare a bimonthly with a monthly regimen of 5-fluorouracil (5-FU) and leucovorin for the adjuvant treatment of colon and high-rectum adenocarcinoma. The bimonthly regimen was administered for 2 consecutive days every 14 days as d,L-leucovorin 200 mg/m2 or L-leucovorin 100 mg/m2 as a 2-hour infusion followed by 5-FU bolus of 400 mg/m2 and a 600 mg/m2 5-FU 22-hour continuous infusion (LVSFU2). In the monthly regimen, d,L-leucovorin 200 mg/m2 or L-leucovorin 100 mg/m2 15-minute infusion followed by a 400 mg/m2 15 minute 5-FU bolus was administered for 5 consecutive days every 28 days (FUFOL). Nine hundred five patients with recently resected stage B2 or C colon or high-rectum adenocarcinoma (inferior pole of the tumor subperitoneal) were recruited into the study. Patients were randomized in a 2 x 2 factorial design to receive either LV5FU2 or FUFOL for 24 or 36 weeks. Characteristics of the patients in the two different treatment groups were similar at baseline. Compliance was good. Mean 5-FU dose intensities were 930 mg/ m2/wk and 463 mg/m2/wk for LVSFU2 and FUFOL, respectively. The incidence of maximal grade III-IV toxicities for LVSFU2 and FUFOL was neutropenia 6% and 16% (P < .001), diarrhea 4% and 10% (P < .001), and mucositis 2% and 7% (P < .001), respectively. Maximum grade III-IV toxicities in the LV5FU2 treatment group were significantly lower than in the FUFOL group (10% v 26%; P < .001). Although patients in the LV5FU2 group received twice the dose of 5-FU compared with those in the FUFOL group, LV5FU2 was shown to be less toxic. Efficacy data will be available in 2001.

  15. Towards a more efficient diabetes control in primary care: six-monthly monitoring compared with three-monthly monitoring in type 2 diabetes - The EFFIMODI trial. Design of a randomised controlled patient-preference equivalence trial in primary care

    Directory of Open Access Journals (Sweden)

    Ardine de Wit G

    2010-05-01

    Full Text Available Abstract Background Scientific evidence for the frequency of monitoring of type 2 diabetes patients is lacking. If three-monthly control in general practice could be reduced to six-monthly control in some patients, this would on the one hand reduce the use of medical services including involvement of practice nurses, and thus reduce costs, and on the other hand alleviate the burden of people with type 2 diabetes. The goal of this study is to make primary diabetes care as efficient as possible for patients and health care providers. Therefore, we want to determine whether six-monthly monitoring of well-controlled type 2 diabetes patients in primary care leads to equivalent cardiometabolic control compared to the generally recommended three-monthly monitoring. Methods and design The study is a randomised controlled patient-preference equivalence trial. Participants are asked if they prefer three-monthly (usual care or six-monthly diabetes monitoring. If they do not have a preference, they are randomised to a three-monthly or six-monthly monitoring group. Patients are eligible for the study if they are between 40 and 80 years old, diagnosed with type 2 diabetes more than one year ago, treated by a general practitioner, not on insulin treatment, and with HbA1c ≤7.5%, systolic blood pressure ≤145 mmHg and total cholesterol ≤5.2 mmol/l. The intervention group (six-monthly monitoring will receive the same treatment with the same treatment targets as the control group (three-monthly monitoring. The intervention period will last one and a half year. After the intervention, the three-monthly and six-monthly monitoring groups are compared on equivalence of cardiometabolic control. Secondary outcome measures are HbA1c, blood pressure, cholesterol level, Body Mass Index, smoking behaviour, physical activity, loss of work due to illness, health status, diabetes-specific distress, satisfaction with treatment and adherence to medications. We will use

  16. Cluster-randomized non-inferiority trial to compare supplement consumption and adherence to different dosing regimens for antenatal calcium and iron-folic acid supplementation to prevent preeclampsia and anaemia: rationale and design of the Micronutrient Initiative study

    Directory of Open Access Journals (Sweden)

    Moshood O. Omotayo

    2015-11-01

    Full Text Available Background: To prevent pre-eclampsia in populations with insufficient dietary calcium (Ca intake, the World Health Organisation (WHO recommends routine Ca supplementation during antenatal care (ANC. WHO guidelines suggest a complex dosing regimen, requiring as many as 5 pill-taking events per day when combined with iron and folic acid (IFA supplements. Poor adherence may undermine public health effectiveness, so simpler regimens may be preferable. This trial will compare the effect of the WHO-recommended (higher-dose regimen vs. a simpler, lower-dose regimen on supplement consumption and pill-taking behaviours in Kenyan ANC clients. Design and methods: This is a parallel, non-inferiority, cluster-randomized trial; we examined 16 primary care health facilities in Kenya, 1047 pregnant women between 16-30 weeks gestational age. Higher-dose regimen: 1.5 g elemental calcium in 3 separate doses (500 mg Ca/pill and IFA (60 mg Fe + 400 μg folic acid taken with evening dose. Lower-dose regimen: 1.0 g calcium in 2 separate doses (500 mg Ca/pill with IFA taken as above. Measurements: Primary outcome is Ca pills consumed per day, measured by pill counts. Secondary outcomes include IFA pills consumed per day, client knowledge, motivation, social support, and satisfaction, measured at 4 to 10 weeks post-enrolment. Statistical analyses: Unit of randomization is the health-care facility; unit of analysis is individual client. Intent-to-treat analysis will be implemented with multi-level models to account for clustering. Expected public health impact: If pregnant women prescribed lower doses of Ca ingest as many pills as women prescribed the WHO-recommended regimen, developing a lower-dose recommendation for antenatal Ca and IFA supplementation programs could save resources.

  17. Design of Randomized, double-blind, Evaluation in secondary Stroke Prevention comparing the EfficaCy and safety of the oral Thrombin inhibitor dabigatran etexilate vs. acetylsalicylic acid in patients with Embolic Stroke of Undetermined Source (RE-SPECT ESUS).

    Science.gov (United States)

    Diener, Hans-Christoph; Easton, J Donald; Granger, Christopher B; Cronin, Lisa; Duffy, Christine; Cotton, Daniel; Brueckmann, Martina; Sacco, Ralph L

    2015-12-01

    Cryptogenic ischemic strokes constitute 20-30% of ischemic strokes, the majority of which are embolic strokes of undetermined source. The standard preventive treatment in these patients is usually acetylsalicylic acid. The Randomized, double-blind, Evaluation in secondary Stroke Prevention comparing the EfficaCy and safety of the oral Thrombin inhibitor dabigatran etexilate vs. acetylsalicylic acid in patients with Embolic Stroke of Undetermined Source (RE-SPECT ESUS) is designed to determine whether the oral thrombin inhibitor dabigatran, taken within three-months after embolic stroke of undetermined source, is superior to acetylsalicylic acid for prevention of recurrent stroke and to characterize the safety of dabigatran in this setting. Prospective, randomized, double-blind, multicenter trial in approximately 6000 patients and 550 centers with embolic stroke of undetermined source. Subjects are randomized to dabigatran or acetylsalicylic acid and treated for an expected minimum of six-months and up to approximately three-years. It is an event-driven trial aiming for 353 adjudicated primary outcome events. The primary efficacy outcome is time to first recurrent stroke (ischemic, hemorrhagic, or unspecified). Key secondary outcomes are time to first ischemic stroke and time to first occurrence in the composite outcome of nonfatal stroke, nonfatal myocardial infarction, and cardiovascular death. The primary safety outcome is major hemorrhage, including symptomatic intracranial hemorrhage. Acetylsalicylic acid is the most common antithrombotic given to patients with embolic strokes of undetermined source to reduce recurrence risk. This trial will determine whether anticoagulation with dabigatran is more effective than acetylsalicylic acid, and acceptably safe. © 2015 World Stroke Organization.

  18. Toward Reduced Aircraft Community Noise Impact Via a Perception-Influenced Design Approach

    Science.gov (United States)

    Rizzi, Stephen A.

    2016-01-01

    This is an exciting time for aircraft design. New configurations, including small multi-rotor uncrewed aerial systems, fixed- and tilt-wing distributed electric propulsion aircraft, high-speed rotorcraft, hybrid-electric commercial transports, and low-boom supersonic transports, are being made possible through a host of propulsion and airframe technology developments. The resulting noise signatures may be radically different, both spectrally and temporally, than those of the current fleet. Noise certification metrics currently used in aircraft design do not necessarily reflect these characteristics and therefore may not correlate well with human response. Further, as operations and missions become less airport-centric, e.g., those associated with on-demand mobility or package delivery, vehicles may operate in closer proximity to the population than ever before. Fortunately, a new set of tools are available for assessing human perception during the design process in order to affect the final design in a positive manner. The tool chain utilizes system noise prediction methods coupled with auralization and psychoacoustic testing, making possible the inclusion of human response to noise, along with performance criteria and certification requirements, into the aircraft design process. Several case studies are considered to illustrate how this approach could be used to influence the design of future aircraft.

  19. Designing Communication Design

    DEFF Research Database (Denmark)

    Løvlie, Anders Sundnes

    2016-01-01

    Innovating in the field of new media genres requires methods for producing designs that can succeed in being disseminated and used outside of design research labs. This article uses the author's experiences with the development of university courses in communication design to address the research...... emphasises rapid techniques for user research and ideation; genre analysis; use of pitching and storytelling as a form of prototyping; and humanist methods for evaluation and critique....

  20. Virtual Optical Comparator

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Greg

    2008-10-20

    The Virtual Optical Comparator, VOC, was conceived as a result of the limitations of conventional optical comparators and vision systems. Piece part designs for mechanisms have started to include precision features on the face of parts that must be viewed using a reflected image rather than a profile shadow. The VOC concept uses a computer generated overlay and a digital camera to measure features on a video screen. The advantage of this system is superior edge detection compared to traditional systems. No vinyl charts are procured or inspected. The part size and expensive fixtures are no longer a concern because of the range of the X-Y table of the Virtual Optical Comparator. Product redesigns require only changes to the CAD image overlays; new vinyl charts are not required. The inspection process is more ergonomic by allowing the operator to view the part sitting at a desk rather than standing over a 30 inch screen. The procurement cost for the VOC will be less than a traditional comparator with a much smaller footprint with less maintenance and energy requirements.

  1. Prompting Designers to Design

    DEFF Research Database (Denmark)

    Ahmed, Saeema

    2006-01-01

    Recent research suggest that engineering designers need assistance to understand what information is relevant for their particular design problem. They require guidance in formulating their queries and also to understand what information is relevant for them. This paper presents an approach...... the system. The distinctive features of this approach is that all the concepts are elicited from the minds of engineering designers, and the system builds up knowledge as more documents enter the system. The approach is based on an understanding obtained from a number of empirical studies and also from...

  2. Prompting Designers to Design

    DEFF Research Database (Denmark)

    Ahmed, Saeema

    2007-01-01

    Recent research suggest that engineering designers need assistance to understand what information is relevant for their particular design problem. They require guidance in formulating their queries and also to understand what information is relevant for them. This paper presents an approach...... the system. The distinctive features of this approach is that all the concepts are elicited from the minds of engineering designers, and the system builds up knowledge as more documents enter the system. The approach is based on an understanding obtained from a number of empirical studies and also from...

  3. Dansk Design

    DEFF Research Database (Denmark)

    Dickson, Thomas

    2006-01-01

    Indhold: Hvad er design?; Hvor kommer dansk design fra?; Produktdesign; Tekstil- og tøjdesign; Design af møbler og boligindretning; Bygningen og design; Arbejdets design; Transportdesign; Offentligt design; Grafisk design; Nye tider og en ny slags design...

  4. On the design of flight-deck procedures

    Science.gov (United States)

    Degani, Asaf; Wiener, Earl L.

    1994-01-01

    In complex human-machine systems, operations, training, and standardization depend on a elaborate set of procedures which are specified and mandated by the operational management of the organization. The intent is to provide guidance to the pilots, to ensure a logical, efficient, safe, and predictable means of carrying out the mission objectives. In this report the authors examine the issue of procedure use and design from a broad viewpoint. The authors recommend a process which we call 'The Four P's:' philosophy, policies, procedures, and practices. We believe that if an organization commits to this process, it can create a set of procedures that are more internally consistent, less confusing, better respected by the flight crews, and that will lead to greater conformity. The 'Four-P' model, and the guidelines for procedural development in appendix 1, resulted from cockpit observations, extensive interviews with airline management and pilots, interviews and discussion at one major airframe manufacturer, and an examination of accident and incident reports. Although this report is based on airline operations, we believe that the principles may be applicable to other complex, high-risk systems, such as nuclear power production, manufacturing process control, space flight, and military operations.

  5. Heartbeat Registration Experiment (Rana Esculenta): Demonstration of the Preparatory Phase. A Case Study in the Design of a Video Presentation for Use in the Physiology Laboratory in the Department of Comparative Physiology at the Rijksuniversiteit Utrecht, Utrecht, the Netherlands.

    Science.gov (United States)

    Earl, F. A.

    This case study describes the design of a video tape presentation for use in a college physiology laboratory. A goal of this color film is to demonstrate to the students those techniques involved in anaesthetising and preparing a frog for a laboratory experiment on the reaction of the heart to electrical and chemical stimuli. The film first shows…

  6. Flexible Wing Designs with Sensor Control Feedback for Demonstration on the X-56A (MUTT)

    Science.gov (United States)

    Ginn, Starr

    2012-01-01

    Presenting an overview of the research DFRC is planning within the Subsonic Fixed Wing (SFW) Light Weight Airframes and Propulsion. Describ ing our TRL maturation and new research going forward using the X-56A as a validation testbed.

  7. A Comparative Analysis of Enlisted Career Progression Systems.

    Science.gov (United States)

    1980-06-01

    Promotional Requirements to Airframe Foreman . . . .. .. .. .. .. .. .. .. 119 xi LIST OF FIGURES Figure Page 1-1. Pyramid of Proposed Research...PERSPECTIVE AND OPINION• /SYSTEMS SURVE Y Fig. 1-1. Pyramid of Proposed Research-- USA? Enlisted Career Progression System 13 3. An examination of alternate...to believe (28:2). McIntire focuses on two of the experts in the field of job motivation and enrichment, Dr. Abraham Maslow and Frederick Herzberg

  8. Análise comparativa do desenho normativo de instituições reguladoras do presente e do passado Comparative analysis of the normative design of former and current regulatory institutions

    Directory of Open Access Journals (Sweden)

    Antonio Gelis Filho

    2006-08-01

    Full Text Available Este artigo desenvolve um modelo matricial para avaliação do desenho normativo de instituições reguladoras do presente e do passado (autarquias econômicas da república "populista". Desenho normativo é definido como o conjunto de possibilidades de estruturação e de atuação de uma instituição que é delimitado pelas normas jurídicas que a criaram. O modelo é estruturado a partir de dois parâmetros principais: independência em relação ao poder central e transparência em relação à sociedade. Foram testadas cinco hipóteses, concluindo-se que as instituições reguladoras do presente apresentam desenhos normativos heterogêneos e que se distinguem de instituições do passado tanto por maior independência quanto por maior transparência, sendo a diferença mais acentuada em relação ao segundo parâmetro.This article develops a matrix model to assess the normative design of past and current regulatory institutions (economic autarchies of the 'populist' republic. Normative design is defined as a set of possibilities for an institution's structure and actions which is limited by the legal norms that created it. The model is structured based on two main parameters: independence in relation to the central power and transparency in relation to society. Five hypothesis were tested, and the conclusion was that current regulatory institutions have heterogeneous designs and they differ from the former ones for being both more independent and more transparent, and the largest difference is in the second parameter.

  9. VLSI design

    CERN Document Server

    Chandrasetty, Vikram Arkalgud

    2011-01-01

    This book provides insight into the practical design of VLSI circuits. It is aimed at novice VLSI designers and other enthusiasts who would like to understand VLSI design flows. Coverage includes key concepts in CMOS digital design, design of DSP and communication blocks on FPGAs, ASIC front end and physical design, and analog and mixed signal design. The approach is designed to focus on practical implementation of key elements of the VLSI design process, in order to make the topic accessible to novices. The design concepts are demonstrated using software from Mathworks, Xilinx, Mentor Graphic

  10. Design concept of three-dimensional section controllable internal waverider hypersonic inlet

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A new hypersonic inlet named three-dimensional section controllable internal waverider inlet is presented in this paper to achieve the goal of section shape geometric transition and complete capture of the upstream mass. On the basis of the association between hypersonic waverider airframe and streamtraced hypersonic inlet, the waverider concept is extended to yield results for the internal flows, namely internal waverider concept. It is proven theoretically that not osculating cones but osculating axisymmetric theory is appropriate for the design of section controllable internal waverider inlet. And two design methods out of the internal waverider concept are proposed subsequently to construct two inlets with specific section shape request, triangle to ellipse and rectangle to ellipse ones. The calculation results show that the inlets are capable of keeping their shock structures and the main flow characteristics exactly as their derived flowfield. Further, the inlets successfully capture all the upstream mass despite their complicated cross-section transitions. It is believed that the concept proposed ex- plores a new way of designing three-dimensional hypersonic inlets with special demand of section shape transition. However, the detailed flow characteristic and the performance of the internal waverider inlets are still under investigation.

  11. Design concept of three-dimensional section controllable internal waverider hypersonic inlet

    Institute of Scientific and Technical Information of China (English)

    YOU YanCheng; LIANG DeWang

    2009-01-01

    A new hypersonic inlet named three-dimensional section controllable internal waverider inlet is presented in this paper to achieve the goal of section shape geometric transition and complete capture of the upstream mass. On the basis of the association between hypersonic waverider airframe and streamtraced hypersonic inlet, the waverider concept is extended to yield results for the internal flows,namely internal waverider concept. It is proven theoretically that not osculating cones but osculating axisymmetric theory is appropriate for the design of section controllable internal wsverider inlet. And two design methods out of the internal waverider concept are proposed subsequently to construct two inlets with specific section shape request, triangle to ellipse and rectangle to ellipse ones. The calculation results show that the inlets are capable of keeping their shock structures and the main flow characteristics exactly as their derived flowfield. Further, the inlets successfully capture all the upstream mass despite their complicated cross-section transitions. It is believed that the concept proposed explores a new way of designing three-dimensional hypersonic inlets with special demand of section shape transition. However, the detailed flow characteristic and the performance of the internal waverider inlets are still under investigation.

  12. Optimal Hospital Layout Design

    DEFF Research Database (Denmark)

    Holst, Malene Kirstine

    This PhD project presents a design model that generates and evaluates hospital designs with respect to long-term performances and functionalities. By visualizing and quantifying costs and performances in the early design phases, it is possible to make design choices based on a qualified, profound...... foundation. The basis of the present study lies in solving the architectural design problem in order to respond to functionalities and performances. The emphasis is the practical applicability for architects, engineers and hospital planners for assuring usability and a holistic approach of functionalities...... and performances. By formal descriptions, a design model can weigh and compare the impact of different perspectives and, even in the early design phase, it can visualize and quantify consequences for design choices. By qualitative study of hospital design and hospital functionality, formal descriptions develop...

  13. Diseño de ejercicio docente basado en el estudio comparativo de metodologías de optimización del mantenimiento // Design of docent exercise based on comparative study between maintenance optimization methodologies

    Directory of Open Access Journals (Sweden)

    Antonio Torres - Valle

    2010-09-01

    Full Text Available La enseñanza basada en problemas constituye un paso importante en la educación de losingenieros. Partiendo del desarrollo de la enseñanza activa, el artículo presenta el diseño de unejercicio docente basado en el estudio comparativo de dos métodos de optimización delmantenimiento: categorización de equipos y mantenimiento centrado en la confiabilidad (RCM eninglés. La aplicación concluye con referencias comparativas de carácter técnico donde sedemuestra la superioridad del segundo método. Finalmente, se establecen recomendaciones para eldiseño técnico metodológico del ejercicio.Palabras claves: mantenimiento, optimización, categorización de equipos, mantenimiento centrado enla confiabilidad, enseñanza basada en problemas, ejercicio docente, recomendaciones metodológicas.__________________________________________________________________________AbstractThe problem based learning is an important step in the education of the engineers. Beginning fromthe development of the active learning the paper presents the design of docent exercise based oncomparative study between two maintenance optimization methodologies: Equipment Categorizationand Reliability Centered Maintenance (RCM. The application concluded with technical comparativereferences, where demonstrates the superiority of the second one. Some recommendations for thetechnical methodological design of exercise are establishes.Key words: maintenance, optimization, equipment categorization, reliability centered maintenanceproblem based learning, docent exercise, methodological recommendations.

  14. A Comparative Study of Teaching Comparative Education

    OpenAIRE

    2007-01-01

    The purpose of this paper is to characterize the comparative education subjects offered in different programs in different foreign universities. As a subject, comparative education has not been firmly institutionalized in education programs in Japanese universities. There was a movement which aimed at making comparative education as one of the mandatory subjects in the teacher training program, however it was not successful. To date, comparative education subject has been offered in various p...

  15. Low Cost Reversible Signed Comparator

    Directory of Open Access Journals (Sweden)

    Farah Sharmin

    2013-10-01

    Full Text Available Nowadays exponential advancement in reversible comp utation has lead to better fabrication and integration process. It has become very popular ove r the last few years since reversible logic circuit s dramatically reduce energy loss. It consumes less p ower by recovering bit loss from its unique input-o utput mapping. This paper presents two new gates called RC-I and RC-II to design an n-bit signed binary comparator where simulation results show that the p roposed circuit works correctly and gives significa ntly better performance than the existing counterparts. An algorithm has been presented in this paper for constructing an optimized reversible n-bit signed c omparator circuit. Moreover some lower bounds have been proposed on the quantum cost, the numbers of g ates used and the number of garbage outputs generated for designing a low cost reversible sign ed comparator. The comparative study shows that the proposed design exhibits superior performance consi dering all the efficiency parameters of reversible logic design which includes number of gates used, quantum cost, garbage output and constant inputs. This proposed design has certainly outperformed all the other existing approaches.

  16. Simulação humana digital na concepção de postos de trabalho: estudo comparativo de casos Digital human simulation for ergonomic workplace design: comparative study of cases

    Directory of Open Access Journals (Sweden)

    Daniel Braatz

    2012-01-01

    Full Text Available Este artigo apresenta como a ferramenta computacional de Modelagem e Simulação Humana contextualizada pela Análise Ergonômica do Trabalho (AET e pela análise da Atividade Futura Possível pode auxiliar nos processos de projeto de postos de trabalho. São analisados dois estudos de caso nos quais a Simulação Humana foi empregada com auxílio do software Jack. O primeiro estudo aborda a concepção de um balcão de atendimento em uma empresa pública de serviços postais. O segundo apresenta o desenvolvimento de uma estação de trabalho de abastecimento de agulhas cirúrgicas em uma empresa de manufatura de produtos relacionados às áreas de saúde e higiene. A partir dos resultados dos estudos de caso, são explicitadas as contribuições e desafios da utilização dessa tecnologia em projetos visando equacionar as questões de saúde e produtividade. O uso da simulação integrada ao processo de intervenção da AET permitiu melhorar a antecipação das futuras atividades prováveis das novas situações de trabalho e auxiliou a integração e comunicação dos atores envolvidos nesses processos sociais.This paper investigates a computational tool for Human Modeling and Simulation contextualized by Ergonomic Analysis of Work (EAW and future work activity forecasting that can assist in the design processes of workplaces. Two case studies using Human Simulation was employed and the software Jack were analyzed. The first study presents the design of a counter in a public post office. The second shows the development of a workstation for the supply of surgical needles in a company that manufactures hygiene and healthcare products. The results of the case studies show the contributions and challenges of using this design technology aiming to solve problems related to health and productivity. The use of simulation combined with EAW helped to improve future work activity forecasting of new work situations and helped the integration and

  17. An Experiment in Comparative Advantage.

    Science.gov (United States)

    Haupert, Michael J.

    1996-01-01

    Describes an undergraduate economics course experiment designed to teach the concepts of comparative advantage and opportunity costs. Students have a limited number of labor hours and can chose to produce either wheat or steel. As the project progresses, the students trade commodities in an attempt to maximize use of their labor hours. (MJP)

  18. Design Anthropology in Participatory Design

    DEFF Research Database (Denmark)

    Smith, Rachel Charlotte; Kjærsgaard, Mette Gislev

    2015-01-01

    This focus section explores the opportunities of design anthropology in participatory design as an approach to research and design in an increasingly global and digital world. Traditionally, ethnography has been used in Participatory design to research real-life contexts and challenges, and as ways...... opportunities of using design anthropology as a holistic and critical approach to addressing societal challenges and change, and a way for anthropologists and designers to engage in participatory research and design that extend beyond the empirical....

  19. Rivaroxaban-once daily, oral, direct factor Xa inhibition compared with vitamin K antagonism for prevention of stroke and Embolism Trial in Atrial Fibrillation: rationale and design of the ROCKET AF study

    DEFF Research Database (Denmark)

    NN, NN

    2010-01-01

    in advanced development as an alternative to warfarin for the prevention and treatment of thromboembolic disorders. METHODS: ROCKET AF is a randomized, double-blind, double-dummy, event-driven trial, which aims to establish the noninferiority of rivaroxaban compared with warfarin in patients with nonvalvular...... nonmajor bleeding events. Over 14,000 patients have been randomized at 1,100 sites across 45 countries, and will be followed until 405 primary outcome events are observed. CONCLUSION: The ROCKET AF study will determine the efficacy and safety of rivaroxaban as an alternative to warfarin for the prevention...

  20. Design Compass

    DEFF Research Database (Denmark)

    Stokholm, Marianne Denise J.

    2006-01-01

    is needed. This paper describes a design concept, in line with the emerging understanding and use of design, and presents a simple tool for support of design management and cooperation in interdisciplinary and intercultural teams. The tool, named “Design Compass”, describes design, not as a profession......, but as a cross field of interacting contexts and places design as both product and process in the centre. It build on a combination of ancient Greek and Roman definitions of man the made and recent models of integrated design by “state of the art” design studios like IDEO. It deals with the interaction...... of contextual based knowledge and values in the design, where integration and optimization acts as the main drive of the process. With this tools design matters can be mapped, described and communicated and knowledge shared among participants in design booth within and among companies and design teams...

  1. The PRICE study (Protection Rest Ice Compression Elevation: design of a randomised controlled trial comparing standard versus cryokinetic ice applications in the management of acute ankle sprain [ISRCTN13903946

    Directory of Open Access Journals (Sweden)

    Rocke Laurence G

    2007-12-01

    Full Text Available Abstract Background Cryotherapy (the application of ice for therapeutic purposes is one of the most common treatment modalities employed in the immediate management of acute soft tissue injury. Despite its widespread clinical use, the precise physiological responses to therapeutic cooling have not been fully elucidated, and effective evidence-based treatment protocols are yet to be established. Intermittent ice applications are thought to exert a significant analgesic effect. This could facilitate earlier therapeutic exercise after injury, potentially allowing for a quicker return to activity. The primary aim of the forthcoming study is therefore to examine the safety and effectiveness of combining intermittent ice applications with periods of therapeutic exercise in the first week after an acute ankle sprain. Methods/Design The study is a randomised controlled trial. 120 subjects with an acute grade I or grade II ankle sprain will be recruited from Accident & Emergency and a University based Sports Injury Clinic. Subjects will be randomised under strict double-blind conditions to either a standard cryotherapy (intermittent ice applications with compression or cryokinetic treatment group (intermittent ice applications with compression and therapeutic exercise. After the first week, treatment will be standardised across groups. Assessor blinding will be maintained throughout the trial. Primary outcome will be function, assessed using the Lower Extremity Functional Scale (LEFS. Additional outcomes will include pain (10 cm Visual Analogue Scale, swelling (modified figure-of-eight method and activity levels (activPAL™ physical activity monitor, PAL Technologies, Glasgow, UK. Diagnostic Ultrasound (Episcan-1-200 high frequency ultrasound scanning system, Longport International Ltd, PA will also be used to assess the degree of soft tissue injury. After baseline assessment subjects will be followed up at 1, 2, 3 & 4 weeks post injury. All data will

  2. Randomized clinical trial comparing percutaneous closure of patent foramen ovale (PFO using the Amplatzer PFO Occluder with medical treatment in patients with cryptogenic embolism (PC-Trial: rationale and design

    Directory of Open Access Journals (Sweden)

    Schuler Gerhard

    2011-02-01

    Full Text Available Abstract Background Several studies have shown an association of cryptogenic stroke and embolism with patent foramen ovale (PFO, but the question how to prevent further events in such patients is unresolved. Options include antithrombotic treatment with warfarin or antiplatelet agents or surgical or endovascular closure of the PFO. The PC-Trial was set up to compare endovascular closure and best medical treatment for prevention of recurrent events. Methods The PC-Trial is a randomized clinical trial comparing the efficacy of percutaneous closure of the PFO using the Amplatzer PFO occluder with best medical treatment in patients with cryptogenic embolism, i.e. mostly cryptogenic stroke. Warfarin for 6 months followed by antiplatelet agents is recommended as medical treatment. Randomization is stratified according to patients age ( Discussion patients were randomized in 29 centers of Europe, Canada, and Australia. Randomization started February 2000. Enrollment of 414 patients was completed in February 2009. All patients will be followed-up longitudinally. Follow-up is maintained until the last enrolled patient is beyond 2.5 years of follow-up (expected in 2011. Trial Registration Trial listed in ClinicalTrials.gov as NCT00166257 and sponsored by AGA Medical, Plymouth, MN, USA

  3. 工业设计下模具制造与3D打印的对比分析%Comparative Analysis of the Lower Mold Manufacturing and Industrial Design 3D Printing

    Institute of Scientific and Technical Information of China (English)

    李建美

    2015-01-01

    3D printing technology after 20 years of development has been known. Although 3D printing will be affected materials, software and processing costs and other factors, but also not really popular, but with the development of science and technology and research efforts continue to increase, 3D printing in the field of industrial design will play a huge role, especially in product manufacturing. With the emergence of 3D printing technology and popularity, and will certainly impact to mold manufacturing-based industrial structure, optimize the industrial chain.%3D打印技术经过20多年的发展,已被人们熟知。虽然3D打印会受到材料、软件和加工成本等因素的影响,还无法真正普及,但随着科学技术的发展和科研力度的不断加大,3D打印在工业设计领域将发挥巨大的作用,尤其是在产品制造方面。随着3D打印技术的出现和普及,必将会冲击以模具制造为主的产业结构,优化产业链条。

  4. A structure-based design of new C2- and C13-substituted taxanes: tubulin binding affinities and extended quantitative structure-activity relationships using comparative binding energy (COMBINE) analysis.

    Science.gov (United States)

    Coderch, Claire; Tang, Yong; Klett, Javier; Zhang, Shu-En; Ma, Yun-Tao; Shaorong, Wang; Matesanz, Ruth; Pera, Benet; Canales, Angeles; Jiménez-Barbero, Jesús; Morreale, Antonio; Díaz, J Fernando; Fang, Wei-Shuo; Gago, Federico

    2013-05-14

    Ten novel taxanes bearing modifications at the C2 and C13 positions of the baccatin core have been synthesized and their binding affinities for mammalian tubulin have been experimentally measured. The design strategy was guided by (i) calculation of interaction energy maps with carbon, nitrogen and oxygen probes within the taxane-binding site of β-tubulin, and (ii) the prospective use of a structure-based QSAR (COMBINE) model derived from an earlier series comprising 47 congeneric taxanes. The tubulin-binding affinity displayed by one of the new compounds (CTX63) proved to be higher than that of docetaxel, and an updated COMBINE model provided a good correlation between the experimental binding free energies and a set of weighted residue-based ligand-receptor interaction energies for 54 out of the 57 compounds studied. The remaining three outliers from the original training series have in common a large unfavourable entropic contribution to the binding free energy that we attribute to taxane preorganization in aqueous solution in a conformation different from that compatible with tubulin binding. Support for this proposal was obtained from solution NMR experiments and molecular dynamics simulations in explicit water. Our results shed additional light on the determinants of tubulin-binding affinity for this important class of antitumour agents and pave the way for further rational structural modifications.

  5. Research Design and Statistical Design.

    Science.gov (United States)

    Szymanski, Edna Mora

    1993-01-01

    Presents fourth editorial in series, this one describing research design and explaining its relationship to statistical design. Research design, validity, and research approaches are examined, quantitative research designs and hypothesis testing are described, and control and statistical designs are discussed. Concludes with section on the art of…

  6. Cluster-Randomized Non-Inferiority Trial to Compare Supplement Consumption and Adherence to Different Dosing Regimens for Antenatal Calcium and Iron-Folic Acid Supplementation to Prevent Preeclampsia and Anaemia: Rationale and Design of the Micronutrient Initiative Study.

    Science.gov (United States)

    Omotayo, Moshood O; Dickin, Katherine L; Chapleau, Gina M; Martin, Stephanie L; Chang, Christopher; Mwanga, Erick O; Kung'u, Jacqueline K; Stoltzfus, Rebecca J

    2015-11-17

    To prevent pre-eclampsia in populations with insufficient dietary calcium (Ca) intake, the World Health Organisation (WHO) recommends routine Ca supplementation during antenatal care (ANC). WHO guidelines suggest a complex dosing regimen, requiring as many as 5 pill-taking events per day when combined with iron and folic acid (IFA) supplements. Poor adherence may undermine public health effectiveness, so simpler regimens may be preferable. This trial will compare the effect of the WHO-recommended (higher-dose) regimen vs. a simpler, lower-dose regimen on supplement consumption and pill-taking behaviours in Kenyan ANC clients. This is a parallel, non-inferiority, cluster-randomized trial; we examined 16 primary care health facilities in Kenya, 1047 pregnant women between 16-30 weeks gestational age. Higher-dose regimen: 1.5 g elemental calcium in 3 separate doses (500 mg Ca/pill) and IFA (60 mg Fe + 400 µg folic acid) taken with evening dose. Lower-dose regimen: 1.0 g calcium in 2 separate doses (500 mg Ca/pill) with IFA taken as above. Primary outcome is Ca pills consumed per day, measured by pill counts. Secondary outcomes include IFA pills consumed per day, client knowledge, motivation, social support, and satisfaction, measured at 4 to 10 weeks post-enrolment. Unit of randomization is the healthcare facility; unit of analysis is individual client. Intent-to-treat analysis will be implemented with multi-level models to account for clustering. If pregnant women prescribed lower doses of Ca ingest as many pills as women prescribed the WHO-recommended regimen, developing a lower-dose recommendation for antenatal Ca and IFA supplementation programs could save resources. Significance for public healthPre-eclampsia is a leading cause of maternal mortality. Based on clinical evidence of significant reduction in risk of pre-eclampsia, the WHO recommends including calcium (Ca) supplementation in antenatal care services in settings with inadequate dietary Ca intakes. A

  7. Comparing effects of soybean oil- and palm olein-based mayonnaise consumption on the plasma lipid and lipoprotein profiles in human subjects: a double-blind randomized controlled trial with cross-over design.

    Science.gov (United States)

    Karupaiah, Tilakavati; Chuah, Khun-Aik; Chinna, Karuthan; Matsuoka, Ryosuke; Masuda, Yasunobu; Sundram, Kalyana; Sugano, Michihiro

    2016-08-17

    Mayonnaise is used widely in contemporary human diet with widespread use as a salad dressing or spread on breads. Vegetable oils used in its formulation may be a rich source of ω-6 PUFAs and the higher-PUFA content of mayonnaise may be beneficial in mediating a hypocholesterolemic effect. This study, therefore, evaluated the functionality of mayonnaise on cardiometabolic risk within a regular human consumption scenario. Subjects underwent a randomized double-blind crossover trial, consuming diets supplemented with 20 g/day of either soybean oil-based mayonnaise (SB-mayo) or palm olein-based mayonnaise (PO-mayo) for 4 weeks each with a 2-week wash-out period. The magnitude of changes for metabolic outcomes between dietary treatments was compared with PO-mayo serving as the control. The data was analyzed by ANCOVA using the GLM model. Analysis was adjusted for weight changes. Treatments resulted in significant reductions in TC (diff = -0.25 mmol/L; P = 0.001), LDL-C (diff = -0.17 mmol/L; P = 0.016) and HDL-C (diff = -0.12 mmol/L; P  0.05). Lipoprotein particle change was significant with large LDL particles increasing after PO-mayo (diff = +63.2 nmol/L; P = 0.007) compared to SB-mayo but small LDL particles remained unaffected. Plasma glucose, apolipoproteins and oxidative stress markers remained unchanged. Daily use with 20 g of linoleic acid-rich SB-mayo elicited reductions in TC and LDL-C concentrations without significantly changing LDL-C:HDL-C ratio or small LDL particle distributions compared to the PO-mayo diet. This clinical trial was retrospectively registered with the National Medical Research Register, National Institute of Health, Ministry of Health Malaysia, (NMRR-15-40-24035; registered on 29/01/2015; https://www.nmrr.gov.my/fwbPage.jsp?fwbPageId=ResearchISRForm&fwbAction=Update&fwbStep=10&pk.researchID=24035&fwbVMenu=3&fwbResearchAction=Update ). Ethical approval was obtained from the National University of

  8. Design and development of a 3D printed UAV

    Science.gov (United States)

    Banfield, Christopher P.

    The purpose of this project was to investigate the viability and practicality of using a desktop 3D printer to fabricate small UAV airframes. To that end, ASTM based bending and tensile tests were conducted to assess the effects of print orientation, infill density, infill pattern, and infill orientation on the structural properties of 3D printed components. A Vernier Structures & Materials Tester was used to record force and displacement data from which stress-strain diagrams, yielding strength, maximum strength, and the moduli of elasticity were found. Results indicated that print orientation and infill density had the greatest impact on strength. In bending, vertically printed test pieces showed the greatest strength, with yield strengths 1.6 - 10.4% higher than conventionally extruded ABS's 64.0MPa average flexural strength. In contrast, the horizontally printed specimens showed yield strengths reduced anywhere from 17.0 - 34.9%. The tensile test specimens also exhibited reduced strength relative to ABS's average tensile yield strength of 40.7MPa. Test pieces with 20% infill density saw strength reductions anywhere from 47.8 - 55.6%, and those with 50% saw strength reductions from 33.6 - 47.8%. Only a single test piece with 100%, 45° crisscross infill achieved tensile performance on par with that of conventionally fabricated ABS. Its yield strength was 43MPa, a positive strength difference of 5.5%. As a supplement to the tensile and bending tests, a prototype printable airplane, the Phoebe, was designed. Its development process in turn provided the opportunity to develop techniques for printing various aircraft components such as fuselage sections, airfoils, and live-in hinges. Initial results seem promising, with the prototype's first production run requiring 19 hours of print time and an additional 4 - 5 hours of assembly time. The maiden flight test demonstrated that the design was stable and controllable in sustained flight.

  9. 中美外部雷电防护系统设计规范比较%Comparation of External Lightning Protection Systems Design Requirements between American Standards and Chinese Standards

    Institute of Scientific and Technical Information of China (English)

    傅剑锋; 杨凯; 徐定成

    2012-01-01

    The related technical requirements of external lightning protection in NFPA 780—2011,such as earthing electrode,downlead,air-termination system,materials of lightning protection system,risk assessment were introduced.NFPA 780—2011 was compared with the related Chinese lightning protection standard,regulations and standards.It could provide reference for more and more overseas project.%从风险评估、防雷系统的材料、接闪器、引下线、接地体等几个方面,介绍了NFPA780—2011外部防雷的相关技术要求,并与中国防雷设计规范的要求进行比较,为海外设计项目提供了设计参考。

  10. Design Anthropology in Participatory Design

    DEFF Research Database (Denmark)

    Smith, Rachel Charlotte; Gislev Kjærsgaard, Mette

    2014-01-01

    In this workshop we explore the opportunities of ethnography and design anthropology in Participatory Design (PD) as an approach to design in an increasingly global and digital world. Traditionally, ethnography has been used in PD to research real-life contexts and challenges, and as ways...... opportunities of using design anthropology as a holistic and critical approach to societal challenges, and a way for anthropologists and designers to engage in design that extends beyond the empirical....

  11. Evidensbaseret design

    DEFF Research Database (Denmark)

    Pagh, Jesper

    2013-01-01

    Debatindlæg om evidensbaseret design, som argumenterer for at det dels er en gammeldags, modernistisk tilgang til design, dels ikke baserer sig på evidens.......Debatindlæg om evidensbaseret design, som argumenterer for at det dels er en gammeldags, modernistisk tilgang til design, dels ikke baserer sig på evidens....

  12. Transformative Design

    DEFF Research Database (Denmark)

    Tamke, Martin; Kobiella, Olaf

    2007-01-01

    The paper presents an architectural design method, which was tested in a master class for four times. It combines the education of complex digital tools with their simultaneous use in the whole design process of an architectural (experimental) building design. The design method contains four steps...

  13. Hypotheses, rationale, design, and methods for prognostic evaluation of cardiac biomarker elevation after percutaneous and surgical revascularization in the absence of manifest myocardial infarction. A comparative analysis of biomarkers and cardiac magnetic resonance. The MASS-V Trial

    Directory of Open Access Journals (Sweden)

    Hueb Whady

    2012-08-01

    Full Text Available Abstract Background Although the release of cardiac biomarkers after percutaneous (PCI or surgical revascularization (CABG is common, its prognostic significance is not known. Questions remain about the mechanisms and degree of correlation between the release, the volume of myocardial tissue loss, and the long-term significance. Delayed-enhancement of cardiac magnetic resonance (CMR consistently quantifies areas of irreversible myocardial injury. To investigate the quantitative relationship between irreversible injury and cardiac biomarkers, we will evaluate the extent of irreversible injury in patients undergoing PCI and CABG and relate it to postprocedural modifications in cardiac biomarkers and long-term prognosis. Methods/Design The study will include 150 patients with multivessel coronary artery disease (CAD with left ventricle ejection fraction (LVEF and a formal indication for CABG; 50 patients will undergo CABG with cardiopulmonary bypass (CPB; 50 patients with the same arterial and ventricular condition indicated for myocardial revascularization will undergo CABG without CPB; and another 50 patients with CAD and preserved ventricular function will undergo PCI using stents. All patients will undergo CMR before and after surgery or PCI. We will also evaluate the release of cardiac markers of necrosis immediately before and after each procedure. Primary outcome considered is overall death in a 5-year follow-up. Secondary outcomes are levels of CK-MB isoenzyme and I-Troponin in association with presence of myocardial fibrosis and systolic left ventricle dysfunction assessed by CMR. Discussion The MASS-V Trial aims to establish reliable values for parameters of enzyme markers of myocardial necrosis in the absence of manifest myocardial infarction after mechanical interventions. The establishments of these indices have diagnostic value and clinical prognosis and therefore require relevant and different therapeutic measures. In daily practice

  14. Design Games

    DEFF Research Database (Denmark)

    Johansson, Martin Wetterstrand

    2007-01-01

    . Experiments can be set up to explore possible futures and design games has the qualities of elegantly focus the work at the same time as it lessens the burden for the process facilitator. The present paper goes into detail about how design games can be set up to facilitate collaboration and how the design......In this paper design games are discussed as an approach to managing design sessions. The focus is on the collaborative design session and more particular on how to set up the collaboration and reinsure progress. Design games have the advantage of framing the collaborative assignment at hand...

  15. FPGA design

    CERN Document Server

    Simpson, Philip

    2010-01-01

    This book describes best practices for successful FPGA design. It is the result of the author's meetings with hundreds of customers on the challenges facing each of their FPGA design teams. By gaining an understanding into their design environments, processes, what works and what does not work, key areas of concern in implementing system designs have been identified and a recommended design methodology to overcome these challenges has been developed. This book's content has a strong focus on design teams that are spread across sites. The goal being to increase the productivity of FPGA design t

  16. Design Games

    DEFF Research Database (Denmark)

    Johansson, Martin Wetterstrand

    2007-01-01

    In this paper design games are discussed as an approach to managing design sessions. The focus is on the collaborative design session and more particular on how to set up the collaboration and reinsure progress. Design games have the advantage of framing the collaborative assignment at hand....... Experiments can be set up to explore possible futures and design games has the qualities of elegantly focus the work at the same time as it lessens the burden for the process facilitator. The present paper goes into detail about how design games can be set up to facilitate collaboration and how the design...

  17. VLSI design

    CERN Document Server

    Basu, D K

    2014-01-01

    Very Large Scale Integrated Circuits (VLSI) design has moved from costly curiosity to an everyday necessity, especially with the proliferated applications of embedded computing devices in communications, entertainment and household gadgets. As a result, more and more knowledge on various aspects of VLSI design technologies is becoming a necessity for the engineering/technology students of various disciplines. With this goal in mind the course material of this book has been designed to cover the various fundamental aspects of VLSI design, like Categorization and comparison between various technologies used for VLSI design Basic fabrication processes involved in VLSI design Design of MOS, CMOS and Bi CMOS circuits used in VLSI Structured design of VLSI Introduction to VHDL for VLSI design Automated design for placement and routing of VLSI systems VLSI testing and testability The various topics of the book have been discussed lucidly with analysis, when required, examples, figures and adequate analytical and the...

  18. Design Management Service in Garment Design

    Institute of Scientific and Technical Information of China (English)

    区晓霞

    2014-01-01

    Purpose This paper discusses the design management concepts and studies application methods of the combination of design and management in garment enterprises. Design/methodology/approach This study emphatical y compares the modes before and after designed, analyzes the dif erences between them and puts forward the feasibility practices in a more ef icient way with the concept of design management. Findings From research and data col ection analysis, it clearly shows that if you can pay more at ention to management in clothing enterprise and integrate garment design relative activities, you wil be bet er to accept the chal enge and catch the competitive advantage. Research limitations/implications This study only studies design management in clothing industry common mode, it did not ful y cover the entire industry. Practical implications This paper analyzes problem in clothing enterprise and put forward some advices and application methods to use the concept of design management. This paper is a practical guide on how this could be done ef ectively. Originality/value Creative and value of this paper is to analyze the traditional model, and on this basis to provide the application of fashion design management mode.

  19. Mechanical design

    CERN Document Server

    Risitano, Antonino

    2011-01-01

    METHODOLOGICAL STATEMENT OF ENGINEERING DESIGNApproaches to product design and developmentMechanical design and environmental requirementsPROPERTIES OF ENGINEERING MATERIALSMaterials for mechanical designCharacterization of metalsStress conditionsFatigue of materialsOptimum material selection in mechanical designDESIGN OF MECHANICAL COMPONENTS AND SYSTEMSFailure theoriesHertz theoryLubrificationShafts and bearingsSplines and keysSpringsFlexible machine elementsSpur gearsPress and shrink fitsPressure tubesCouplingsClutchesBrakes

  20. Comparative Multi-Criteria Assessment of Climate Policies and Sustainable Development Strategies in Cameroon: Towards a GIS Decision-Support Tool for the Design of an Optimal REDD+ Strategy

    Directory of Open Access Journals (Sweden)

    Anderson Gwanyebit Kehbila

    2014-09-01

    Full Text Available Cameroon is committed to reducing emissions from deforestation and forest degradation plus conservation, sustainable management of forests and enhancement of carbon stocks (REDD+. To achieve this goal, the government has introduced a series of policy reforms and formulated a number of key strategic planning documents to advance the REDD+ readiness process in Cameroon. This paper assesses the extent to which major cross-sectoral policies support or impede the development and implementation of an optimal REDD+ strategy in Cameroon from a comparative multi-criteria perspective. Study results reveal that a majority of the policy instruments reviewed appeared to be less prescriptive in terms of any tangible REDD+ strategy, as they do not have provisions for tangible measures to reduce deforestation and forest degradation. Given the lack of adequate flexibility, prompt review and responsiveness of these cross-sectoral policies to adapt themselves to new realities and respond to a changing environment, this paper introduces a GIS-REDD+ decision support system (GIS-REDD+DSS that is necessary to support the adaptive element of an adaptive REDD+ strategy in Cameroon. The GIS-REDD+DSS, an electronic REDD+agri intermediary hub, serves the following purpose: (1 host a database of locally-relevant climate information, improved input technologies, best practices as well as land use and forest cover geo-spatial maps; (2 host a virtual economic tool that performs economic valuations (costs and benefits and financial analysis of REDD+agri projects to aid investment decision-making; and (3 host an electronic marketplace to mediate any-to-any transactions among REDD+agri project developers, service providers, input suppliers, private and institutional investors and buyers (wholesalers and retailers, thereby creating value in two ways: aggregation and matching. This decision support tool, we argue, is a fundamental prerequisite for “policy and REDD+ safeguard