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Sample records for precision machining applications

  1. Ultra precision machining

    NASA Astrophysics Data System (ADS)

    Debra, Daniel B.; Hesselink, Lambertus; Binford, Thomas

    1990-05-01

    There are a number of fields that require or can use to advantage very high precision in machining. For example, further development of high energy lasers and x ray astronomy depend critically on the manufacture of light weight reflecting metal optical components. To fabricate these optical components with machine tools they will be made of metal with mirror quality surface finish. By mirror quality surface finish, it is meant that the dimensions tolerances on the order of 0.02 microns and surface roughness of 0.07. These accuracy targets fall in the category of ultra precision machining. They cannot be achieved by a simple extension of conventional machining processes and techniques. They require single crystal diamond tools, special attention to vibration isolation, special isolation of machine metrology, and on line correction of imperfection in the motion of the machine carriages on their way.

  2. Precision Robotic Assembly Machine

    ScienceCinema

    None

    2016-07-12

    The world's largest laser system is the National Ignition Facility (NIF), located at Lawrence Livermore National Laboratory. NIF's 192 laser beams are amplified to extremely high energy, and then focused onto a tiny target about the size of a BB, containing frozen hydrogen gas. The target must be perfectly machined to incredibly demanding specifications. The Laboratory's scientists and engineers have developed a device called the "Precision Robotic Assembly Machine" for this purpose. Its unique design won a prestigious R&D-100 award from R&D Magazine.

  3. Precision Robotic Assembly Machine

    SciTech Connect

    2009-08-14

    The world's largest laser system is the National Ignition Facility (NIF), located at Lawrence Livermore National Laboratory. NIF's 192 laser beams are amplified to extremely high energy, and then focused onto a tiny target about the size of a BB, containing frozen hydrogen gas. The target must be perfectly machined to incredibly demanding specifications. The Laboratory's scientists and engineers have developed a device called the "Precision Robotic Assembly Machine" for this purpose. Its unique design won a prestigious R&D-100 award from R&D Magazine.

  4. Prediction of the applicability of active damping elements in high-precision machines

    NASA Astrophysics Data System (ADS)

    Holterman, Jan; de Vries, Theo J. A.

    2004-07-01

    The Smart Disc project at the Drebbel Institute of the University of Twente is aimed at the development of active structural elements for high-precision machines. The active elements consist of a piezoelectric position actuator and a collocated piezoelectric force sensor. As the actuators and sensors are collocated, the elements are especially suited for implementing robust active damping. The decision whether or not to incorporate active damping elements in a high-precision machine should ideally be made in an early design stage, i.e., at a time at which only limited knowledge of the vibration problem is available. Despite the uncertainties that may exist at that stage, one would like to be able to roughly predict the amount of damping that could possibly be obtained. For that reason, the present paper is concerned with the development of an analysis tool that may help in predicting the applicability of active damping elements in a mechanical structure of which only a rough model is available. Based on extensive simulations, several practical rules of thumb are given for the requirements for the mechanical structure and the active elements, in order to enable the realisation of relative damping values as high as 10%.

  5. Principles and techniques for designing precision machines

    SciTech Connect

    Hale, L C

    1999-02-01

    This thesis is written to advance the reader's knowledge of precision-engineering principles and their application to designing machines that achieve both sufficient precision and minimum cost. It provides the concepts and tools necessary for the engineer to create new precision machine designs. Four case studies demonstrate the principles and showcase approaches and solutions to specific problems that generally have wider applications. These come from projects at the Lawrence Livermore National Laboratory in which the author participated: the Large Optics Diamond Turning Machine, Accuracy Enhancement of High- Productivity Machine Tools, the National Ignition Facility, and Extreme Ultraviolet Lithography. Although broad in scope, the topics go into sufficient depth to be useful to practicing precision engineers and often fulfill more academic ambitions. The thesis begins with a chapter that presents significant principles and fundamental knowledge from the Precision Engineering literature. Following this is a chapter that presents engineering design techniques that are general and not specific to precision machines. All subsequent chapters cover specific aspects of precision machine design. The first of these is Structural Design, guidelines and analysis techniques for achieving independently stiff machine structures. The next chapter addresses dynamic stiffness by presenting several techniques for Deterministic Damping, damping designs that can be analyzed and optimized with predictive results. Several chapters present a main thrust of the thesis, Exact-Constraint Design. A main contribution is a generalized modeling approach developed through the course of creating several unique designs. The final chapter is the primary case study of the thesis, the Conceptual Design of a Horizontal Machining Center.

  6. Precision Machining Technology. Curriculum Guide.

    ERIC Educational Resources Information Center

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

    This curriculum guide was developed from a Technical Committee Report prepared with the assistance of industry personnel and containing a Task List which is the basis of the guide. It presents competency-based program standards for courses in precision machining technology and is part of the Idaho Vocational Curriculum Guide Project, a cooperative…

  7. The laser micro-machining system for diamond anvil cell experiments and general precision machining applications at the High Pressure Collaborative Access Team

    SciTech Connect

    Hrubiak, Rostislav; Sinogeikin, Stanislav; Rod, Eric; Shen, Guoyin

    2015-07-15

    We have designed and constructed a new system for micro-machining parts and sample assemblies used for diamond anvil cells and general user operations at the High Pressure Collaborative Access Team, sector 16 of the Advanced Photon Source. The new micro-machining system uses a pulsed laser of 400 ps pulse duration, ablating various materials without thermal melting, thus leaving a clean edge. With optics designed for a tight focus, the system can machine holes any size larger than 3 μm in diameter. Unlike a standard electrical discharge machining drill, the new laser system allows micro-machining of non-conductive materials such as: amorphous boron and silicon carbide gaskets, diamond, oxides, and other materials including organic materials such as polyimide films (i.e., Kapton). An important feature of the new system is the use of gas-tight or gas-flow environmental chambers which allow the laser micro-machining to be done in a controlled (e.g., inert gas) atmosphere to prevent oxidation and other chemical reactions in air sensitive materials. The gas-tight workpiece enclosure is also useful for machining materials with known health risks (e.g., beryllium). Specialized control software with a graphical interface enables micro-machining of custom 2D and 3D shapes. The laser-machining system was designed in a Class 1 laser enclosure, i.e., it includes laser safety interlocks and computer controls and allows for routine operation. Though initially designed mainly for machining of the diamond anvil cell gaskets, the laser-machining system has since found many other micro-machining applications, several of which are presented here.

  8. The laser micro-machining system for diamond anvil cell experiments and general precision machining applications at the High Pressure Collaborative Access Team

    NASA Astrophysics Data System (ADS)

    Hrubiak, Rostislav; Sinogeikin, Stanislav; Rod, Eric; Shen, Guoyin

    2015-07-01

    We have designed and constructed a new system for micro-machining parts and sample assemblies used for diamond anvil cells and general user operations at the High Pressure Collaborative Access Team, sector 16 of the Advanced Photon Source. The new micro-machining system uses a pulsed laser of 400 ps pulse duration, ablating various materials without thermal melting, thus leaving a clean edge. With optics designed for a tight focus, the system can machine holes any size larger than 3 μm in diameter. Unlike a standard electrical discharge machining drill, the new laser system allows micro-machining of non-conductive materials such as: amorphous boron and silicon carbide gaskets, diamond, oxides, and other materials including organic materials such as polyimide films (i.e., Kapton). An important feature of the new system is the use of gas-tight or gas-flow environmental chambers which allow the laser micro-machining to be done in a controlled (e.g., inert gas) atmosphere to prevent oxidation and other chemical reactions in air sensitive materials. The gas-tight workpiece enclosure is also useful for machining materials with known health risks (e.g., beryllium). Specialized control software with a graphical interface enables micro-machining of custom 2D and 3D shapes. The laser-machining system was designed in a Class 1 laser enclosure, i.e., it includes laser safety interlocks and computer controls and allows for routine operation. Though initially designed mainly for machining of the diamond anvil cell gaskets, the laser-machining system has since found many other micro-machining applications, several of which are presented here.

  9. The laser micro-machining system for diamond anvil cell experiments and general precision machining applications at the High Pressure Collaborative Access Team.

    PubMed

    Hrubiak, Rostislav; Sinogeikin, Stanislav; Rod, Eric; Shen, Guoyin

    2015-07-01

    We have designed and constructed a new system for micro-machining parts and sample assemblies used for diamond anvil cells and general user operations at the High Pressure Collaborative Access Team, sector 16 of the Advanced Photon Source. The new micro-machining system uses a pulsed laser of 400 ps pulse duration, ablating various materials without thermal melting, thus leaving a clean edge. With optics designed for a tight focus, the system can machine holes any size larger than 3 μm in diameter. Unlike a standard electrical discharge machining drill, the new laser system allows micro-machining of non-conductive materials such as: amorphous boron and silicon carbide gaskets, diamond, oxides, and other materials including organic materials such as polyimide films (i.e., Kapton). An important feature of the new system is the use of gas-tight or gas-flow environmental chambers which allow the laser micro-machining to be done in a controlled (e.g., inert gas) atmosphere to prevent oxidation and other chemical reactions in air sensitive materials. The gas-tight workpiece enclosure is also useful for machining materials with known health risks (e.g., beryllium). Specialized control software with a graphical interface enables micro-machining of custom 2D and 3D shapes. The laser-machining system was designed in a Class 1 laser enclosure, i.e., it includes laser safety interlocks and computer controls and allows for routine operation. Though initially designed mainly for machining of the diamond anvil cell gaskets, the laser-machining system has since found many other micro-machining applications, several of which are presented here.

  10. Precision machining technology and metrology for AXAF study

    NASA Technical Reports Server (NTRS)

    Sanger, G. M.

    1983-01-01

    The optical surfaces for the Advanced X-ray Astrophysical Facility (AXAF), was studied. The applicability of precision machining technology to the manufacture of the AXAF objective mirrors and the proposed and alternative methods for manufacturing and testing; (1) the AXAF technology mirrors and (2) the AXAF high resolution mirror assembly were reviewed. Surface shape and smoothness metrology for grazing incidence X-ray surfaces and the feasibility of applying heterodyne surface profilometry to nonflat surfaces were investigated. Three sets of scattering flats with known surface profiles and microtopographic character produced by precision machining and polished precision machine surfaces were analyzed.

  11. Micro Machining Enhances Precision Fabrication

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Advanced thermal systems developed for the Space Station Freedom project are now in use on the International Space Station. These thermal systems employ evaporative ammonia as their coolant, and though they employ the same series of chemical reactions as terrestrial refrigerators, the space-bound coolers are significantly smaller. Two Small Business Innovation Research (SBIR) contracts between Creare Inc. of Hanover, NH and Johnson Space Center developed an ammonia evaporator for thermal management systems aboard Freedom. The principal investigator for Creare Inc., formed Mikros Technologies Inc. to commercialize the work. Mikros Technologies then developed an advanced form of micro-electrical discharge machining (micro-EDM) to make tiny holes in the ammonia evaporator. Mikros Technologies has had great success applying this method to the fabrication of micro-nozzle array systems for industrial ink jet printing systems. The company is currently the world leader in fabrication of stainless steel micro-nozzles for this market, and in 2001 the company was awarded two SBIR research contracts from Goddard Space Flight Center to advance micro-fabrication and high-performance thermal management technologies.

  12. Precision Machining Technology. Technical Committee Report.

    ERIC Educational Resources Information Center

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

    This Technical Committee Report prepared by industry representatives in Idaho lists the skills currently necessary for an employee in that state to obtain a job in precision machining technology, retain a job once hired, and advance in that occupational field. (Task lists are grouped according to duty areas generally used in industry settings, and…

  13. Diamond Machining Applications And Capabilities

    NASA Astrophysics Data System (ADS)

    Benjamin, Roland J.

    1983-12-01

    Aspheric surface generation and precision machining have been important technologies at Hughes Optical Products, Inc. (formerly Optical Division, Bell & Howell Company) for over twenty years. Present machining capabilities and supporting services which are available on a custom basis are described. A variety of applications of diamond machining are illustrated, involving not only the usual reflective materials such as aluminum, copper, and electroless nickel but also such IR refractive materials as germanium, silicon, and chalcogenide glasses.

  14. A New Approach to Precision Design for Machine Tools

    NASA Astrophysics Data System (ADS)

    Li, Baodong; Jiao, Aisheng; Yi, Xiangbin; Xu, Yanwei

    Precision of the NC axes is an important aspect of machine tool design. Conventionally, the precision specification of machine tools is empirically determined, resulting in poor designs with insufficient or excessive precision. To provide a cost-effective precision specification for machine tools, an active precision design approach is proposed to generate the specification of the positioning repeatability of NC axes to meet the designated working precision requirements of the machine tools. Finally, the approach is demonstrated and validated through a case study of precision design for a gear milling machine.

  15. Perspective on precision machining, polishing, and optical requirements

    SciTech Connect

    Sanger, G.M.

    1981-08-18

    While precision machining has been applied to the manufacture of optical components for a considerable period, the process has, in general, had its thinking restricted to producing only the accurate shapes required. The purpose of this paper is to show how optical components must be considered from an optical (functional) point of view and that the manufacturing process must be selected on that basis. To fill out this perspective, simplistic examples of how optical components are specified with respect to form and finish are given, a comparison between optical polishing and precision machining is made, and some thoughts on which technique should be selected for a specific application are presented. A short discussion of future trends related to accuracy, materials, and tools is included.

  16. Research on machining error compensation in high-precision surface grinding machine for optical aspheric elements

    NASA Astrophysics Data System (ADS)

    Ke, Xiaolong; Guo, Yinbiao; Zhang, Shihan; Huang, Hao

    2010-10-01

    Using aspheric component in optical system can correct optical aberration, acquire high imaging quality, improve the optical characteristic, simplify system structure, and reduce system volume. Nowadays, high-precision surface grinding machine is an important approach to processing optical aspheric elements. However, because of the characteristics of optical aspheric elements, the processing method makes a higher demand to whole performance of surface grinding machine, and hardly to achieve ideal machining effect. Taking high generality and efficiency into account, this paper presents a compensation method for machining errors of high-precision surface grinding machine, which bases on optical aspheric elements, to achieve high-precision machining for all kinds of optical aspheric elements. After compensation, the machining accuracy of grinding machine could reach 2um/200×200mm. The research bases on NC surface grinding machine which is self developed. First of all, this paper introduces machining principle for optical aspheric elements on the grinding machine. And then error sources which producing errors are analyzed. By contacting and non-contacting measurement sensors, measurement software which is self designed realizes on-position measure for grinded workpiece, then fits surface precision and machining errors. Through compensation software for machining error which is self designed, compensation algorithm is designed and translated compensation data into G-code for the high-precision grinding machine to achieve compensation machining. Finally, by comparison between machining error compensation before and after processing, the experiments for this purpose are done to validate the compensation machining accuracy.

  17. Precision machining of pig intestine using ultrafast laser pulses

    NASA Astrophysics Data System (ADS)

    Beck, Rainer J.; Góra, Wojciech S.; Carter, Richard M.; Gunadi, Sonny; Jayne, David; Hand, Duncan P.; Shephard, Jonathan D.

    2015-07-01

    Endoluminal surgery for the treatment of early stage colorectal cancer is typically based on electrocautery tools which imply restrictions on precision and the risk of harm through collateral thermal damage to the healthy tissue. As a potential alternative to mitigate these drawbacks we present laser machining of pig intestine by means of picosecond laser pulses. The high intensities of an ultrafast laser enable nonlinear absorption processes and a predominantly nonthermal ablation regime. Laser ablation results of square cavities with comparable thickness to early stage colorectal cancers are presented for a wavelength of 1030 nm using an industrial picosecond laser. The corresponding histology sections exhibit only minimal collateral damage to the surrounding tissue. The depth of the ablation can be controlled precisely by means of the pulse energy. Overall, the application of ultrafast lasers to ablate pig intestine enables significantly improved precision and reduced thermal damage to the surrounding tissue compared to conventional techniques.

  18. Tool simplifies machining of pipe ends for precision welding

    NASA Technical Reports Server (NTRS)

    Matus, S. T.

    1969-01-01

    Single tool prepares a pipe end for precision welding by simultaneously performing internal machining, end facing, and bevel cutting to specification standards. The machining operation requires only one milling adjustment, can be performed quickly, and produces the high quality pipe-end configurations required to ensure precision-welded joints.

  19. Program Guide for Basic Precision Machining 8754000 (IN48.052300) and Precision Machining MTR0470 (IN48.050300).

    ERIC Educational Resources Information Center

    University of South Florida, Tampa. Dept. of Adult and Vocational Education.

    This competency-based program guide provides course content information and procedures for secondary schools, postsecondary vocational schools, and community colleges in Florida that conduct programs in basic precision machining and precision machining. The first section is on legal authority, which applies to all vocational education programs in…

  20. Toward a metrology for precision-machine-tool control systems

    SciTech Connect

    Pomernacki, C.L.; McCue, H.K.; Newton, L.E.

    1982-07-20

    The difficulty of determining the source of an error in the performance of the control system of a computer numerically controlled (CNC) precision machine tool is discussed and recommendations are made for error isolation using the Machine Control System Meterology Tree. These recommendations refer to types of tests for specific errors and to a possible architecture for a CNC performance tester. It is concluded that there is a need for both a control system metrology and for establishing standards of performance and testing methods for precision machine tool control systems. (LCL)

  1. Toward a metrology for precision-machine-tool control systems

    NASA Astrophysics Data System (ADS)

    Pomernacki, C. L.; McCue, H. K.; Newton, L. E.

    1982-07-01

    The difficulty of determining the source of an error in the performance of the control system of a computer numerically controlled (CNC) precision machine tool is discussed and recommendations are made for error isolation using the Machine Control System Meterology Tree. These recommendations refer to types of tests for specific errors and to a possible architecture for a CNC performance tester. It is concluded that there is a need for both a control system metrology and for establishing standards of performance and testing methods for precision machine tool control systems.

  2. Precision Machining Technologies. Occupational Competency Analysis Profile.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Vocational Instructional Materials Lab.

    This Occupational Competency Analysis Profile (OCAP), which is one of a series of OCAPs developed to identify the skills that Ohio employers deem necessary to entering a given occupation/occupational area, lists the occupational, academic, and employability skills required of individuals entering the occupation of precision machinist. The…

  3. Machining of beryllium with the LLNL Precision Engineering Research Lathe

    SciTech Connect

    Foley, R.J.

    1985-04-01

    In August 1984, six flat samples of beryllium, which were prepared by Brush-Wellmen Corp. using various pressing and sintering processes, were machined at LLNL on the recently completed Precision Engineering Research Lathe (PERL). The purpose of this study, which was conducted in cooperation with the Hughes Aircraft Corporation and partially funded by that organization, was to determine the optical properties of machined beryllium surfaces when prepared under highly controlled conditions using high quality machine tools and CBN (cubic boron nitrite) cutting tools. This report will summarize the materials properties, the machining conditions used on the PERL and a comparison of the completed samples using optical measuring techniques and scanning electron microscopy (SEM). The mirror surface reflecting measurements in the IR region are to be made by the group at Hughes Aircraft and will be exchanged with LLNL as a part of this joint technical effort. 3 refs., 14 figs.

  4. High-precision micro/nano-scale machining system

    DOEpatents

    Kapoor, Shiv G.; Bourne, Keith Allen; DeVor, Richard E.

    2014-08-19

    A high precision micro/nanoscale machining system. A multi-axis movement machine provides relative movement along multiple axes between a workpiece and a tool holder. A cutting tool is disposed on a flexible cantilever held by the tool holder, the tool holder being movable to provide at least two of the axes to set the angle and distance of the cutting tool relative to the workpiece. A feedback control system uses measurement of deflection of the cantilever during cutting to maintain a desired cantilever deflection and hence a desired load on the cutting tool.

  5. Sensor and actuator considerations for precision, small machines: a review

    SciTech Connect

    Smith, S T; Seugling, R M

    2005-04-04

    This article reviews some design considerations for the scaling down in size of instruments and machines with a primary aim to identify technologies that may provide more optimal performance solutions than those, often established, technologies used at macroscopic, or conventional, scales. Dimensional metrology within emerging applications will be considered for meso- through micro-down to nanometer level systems with particular emphasis on systems for which precision is directly related to function. In this paper, attention is limited to some of the more fundamental issues associated with scaling. For example, actuator work or power densities or the effect of noise on the sensor signals can be readily evaluated and provide some guidance in the selection for any given size of device. However, with reductions in scale these parameters and/or phenomena that limit performance may change. Within this review, the authors have tried to assess these complex inter-relationships between performance and scale, again from a fundamental perspective. In practice, it is likely that the nuances of implementation and integration of sensor, actuator and/or mechanism designs will determine functionality and commercial viability of any particular system development.

  6. The design of an ultra-precision CNC measuring machine

    SciTech Connect

    Thompson, D.C.

    1989-01-01

    A specialized ultra-precision CNC measuring machine is being developed to provide an inspection capability compatible with existing precision turning machines. The instrument is to be applied to the inspection of the inner and outer surfaces of hemispherical shells and other axisymmetric parts, with diameters of up to 400 mm. The overall accuracy of the machine operating in continuous path contouring mode is to be less than 0.75 micrometre (p-v) per surface, including both instrument and process-related errors. In addition, an accuracy of 1.75 micrometres is required for the inspection of wall thickness on some categories of parts, which in some instances may be distorted by gravity loading. This latter requirement dictates a single setup for the inspection of inner and outer surfaces, and effectively eliminates a standard Coordinate Measuring Machine (CMM) configuration for the new gauge. The new instrument is known as the Certification of Process (COP) Gauge. 9 refs., 5 figs., 2 tabs.

  7. Protein function in precision medicine: deep understanding with machine learning.

    PubMed

    Rost, Burkhard; Radivojac, Predrag; Bromberg, Yana

    2016-08-01

    Precision medicine and personalized health efforts propose leveraging complex molecular, medical and family history, along with other types of personal data toward better life. We argue that this ambitious objective will require advanced and specialized machine learning solutions. Simply skimming some low-hanging results off the data wealth might have limited potential. Instead, we need to better understand all parts of the system to define medically relevant causes and effects: how do particular sequence variants affect particular proteins and pathways? How do these effects, in turn, cause the health or disease-related phenotype? Toward this end, deeper understanding will not simply diffuse from deeper machine learning, but from more explicit focus on understanding protein function, context-specific protein interaction networks, and impact of variation on both. PMID:27423136

  8. Surface errors in the course of machining precision optics

    NASA Astrophysics Data System (ADS)

    Biskup, H.; Haberl, A.; Rascher, R.

    2015-08-01

    Precision optical components are usually machined by grinding and polishing in several steps with increasing accuracy. Spherical surfaces will be finished in a last step with large tools to smooth the surface. The requested surface accuracy of non-spherical surfaces only can be achieved with tools in point contact to the surface. So called mid-frequency errors (MSFE) can accumulate with zonal processes. This work is on the formation of surface errors from grinding to polishing by conducting an analysis of the surfaces in their machining steps by non-contact interferometric methods. The errors on the surface can be distinguished as described in DIN 4760 whereby 2nd to 3rd order errors are the so-called MSFE. By appropriate filtering of the measured data frequencies of errors can be suppressed in a manner that only defined spatial frequencies will be shown in the surface plot. It can be observed that some frequencies already may be formed in the early machining steps like grinding and main-polishing. Additionally it is known that MSFE can be produced by the process itself and other side effects. Beside a description of surface errors based on the limits of measurement technologies, different formation mechanisms for selected spatial frequencies are presented. A correction may be only possible by tools that have a lateral size below the wavelength of the error structure. The presented considerations may be used to develop proposals to handle surface errors.

  9. Standard surface grinder for precision machining of thin-wall tubing

    NASA Technical Reports Server (NTRS)

    Jones, A.; Kotora, J., Jr.; Rein, J.; Smith, S. V.; Strack, D.; Stuckey, D.

    1967-01-01

    Standard surface grinder performs precision machining of thin-wall stainless steel tubing by electrical discharge grinding. A related adaptation, a traveling wire electrode fixture, is used for machining slots in thin-walled tubing.

  10. Using hyperspectral data in precision farming applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Precision farming practices such as variable rate applications of fertilizer and agricultural chemicals require accurate field variability mapping. This chapter investigated the value of hyperspectral remote sensing in providing useful information for five applications of precision farming: (a) Soil...

  11. Applications of Machine Learning in Information Retrieval.

    ERIC Educational Resources Information Center

    Cunningham, Sally Jo; Witten, Ian H.; Littin, James

    1999-01-01

    Introduces the basic ideas that underpin applications of machine learning to information retrieval. Describes applications of machine learning to text categorization. Considers how machine learning can be applied to the query-formulation process. Examines methods of document filtering, where the user specifies a query that is to be applied to an…

  12. Effects of imbalance and geometric error on precision grinding machines

    SciTech Connect

    Bibler, J.E.

    1997-06-01

    To study balancing in grinding, a simple mechanical system was examined. It was essential to study such a well-defined system, as opposed to a large, complex system such as a machining center. The use of a compact, well-defined system enabled easy quantification of the imbalance force input, its phase angle to any geometric decentering, and good understanding of the machine mode shapes. It is important to understand a simple system such as the one I examined given that imbalance is so intimately coupled to machine dynamics. It is possible to extend the results presented here to industrial machines, although that is not part of this work. In addition to the empirical testing, a simple mechanical system to look at how mode shapes, balance, and geometric error interplay to yield spindle error motion was modelled. The results of this model will be presented along with the results from a more global grinding model. The global model, presented at ASPE in November 1996, allows one to examine the effects of changing global machine parameters like stiffness and damping. This geometrically abstract, one-dimensional model will be presented to demonstrate the usefulness of an abstract approach for first-order understanding but it will not be the main focus of this thesis. 19 refs., 36 figs., 10 tables.

  13. Simulation of precision electrochemical machining of metals by a segmented cathode

    NASA Astrophysics Data System (ADS)

    Zhitnikov, V. P.; Oshmarina, E. M.; Zinnatullina, A. R.

    2011-12-01

    Bulge formation in the process of electrochemical machining by a flat tool electrode with an insulated area is studied. Based on a step function of the current efficiency, precision machining is simulated. The solution of a nonstationary problem shows that a limiting mode with the current density equal to its critical value is established in a finite time.

  14. Aspects of ultra-high-precision diamond machining of RSA 443 optical aluminium

    NASA Astrophysics Data System (ADS)

    Mkoko, Z.; Abou-El-Hossein, K.

    2015-08-01

    Optical aluminium alloys such as 6061-T6 are traditionally used in ultra-high precision manufacturing for making optical mirrors for aerospace and other applications. However, the optics industry has recently witnessed the development of more advanced optical aluminium grades that are capable of addressing some of the issues encountered when turning with single-point natural monocrystalline diamond cutters. The advent of rapidly solidified aluminium (RSA) grades has generally opened up new possibilities for ultra-high precision manufacturing of optical components. In this study, experiments were conducted with single-point diamond cutters on rapidly solidified aluminium RSA 443 material. The objective of this study is to observe the effects of depth of cut and feed rate at a fixed rotational speed on the tool wear rate and resulting surface roughness of diamond turned specimens. This is done to gain further understanding of the rate of wear on the diamond cutters versus the surface texture generated on the RSA 443 material. The diamond machining experiments yielded machined surfaces which are less reflective but with consistent surface roughness values. Cutting tools were observed for wear through scanning microscopy; relatively low wear pattern was evident on the diamond tool edge. The highest tool wear were obtained at higher depth of cut and increased feed rate.

  15. On Precision of Recurrent Higher-Order Neural Network that Simulates Turing Machines

    NASA Astrophysics Data System (ADS)

    Tanaka, Ken

    When a neural network simulates a Turing machine, the states of finite state controller and the symbols on infinite tape are encoded in continuous numbers of neuron's outputs. The precision of outputs is regarded as a space resource in neural computations. We show a sufficient condition about the precision to guarantee the correctness of computations. Linear precision suffice in regard to nT, where n is the number of neurons and T is the iteration count of state updates.

  16. Applications of the connection machine

    SciTech Connect

    Waltz, D.L.

    1987-01-01

    The Connection Machine development effort was initiated in the belief that parallel processing and artificial intelligence could together accelerate the rate of progress toward truly intelligent machines. This progress is the result of the ease with which the machine can be programmed and the dramatic increase in compute power that the machine can bring to bear. The authors have been able to run many trials of experiments in instances where previously, running just one would have been considered an achievement and no further experimentation would have been done. This has enabled exploring a great many more hypotheses and to work on much larger problems that had been possible on previous-generation artificial intelligence workstations. The ease of programming is in part the result of a decision to use existing serial machines (the Symbolics 3600 or Digital Equipment Corporation VAX), thus leaving unchanged the operating systems, editors, file systems, debuggers, network communications systems, and so on, so as to provide familiar programming environments. The Connection Machine is programmed in conservative extensions of Common Lisp and C. Users familiar with these languages and with front-end computer systems have been able to produce results on the Connection Machine on the first day that they use it.

  17. Ultra-precision cutting of Fresnel lenses on single crystal germanium and the machining processing analysis

    NASA Astrophysics Data System (ADS)

    Fan, Yufeng; Zhu, Yongjian; Pan, Weiqing

    2010-10-01

    Single crystal germanium is used in infrared spectroscopes and other optical equipment as an excellent infrared optical material. The development of germanium Fresnel lenses not only improves the optical imaging quality but also enables the miniaturization of optical systems. In a previous work, a Fresnel lens with precise curvatures, sharp edges and precise cross-sectional profiles were fabricated. However, sometimes, microcracks will occur to the edge of grooves when the wear of the diamond tool is large in the machining process. In the present work, in order to minimize the effect of the tool tip wear to the groove edge of Fresnel lens, a novel machining process and machining conditions are proposed for fabricating a high-precision Fresnel lens.

  18. Comparison between predicted and actual accuracies for an Ultra-Precision CNC measuring machine

    SciTech Connect

    Thompson, D.C.; Fix, B.L.

    1995-05-30

    At the 1989 CIRP annual meeting, we reported on the design of a specialized, ultra-precision CNC measuring machine, and on the error budget that was developed to guide the design process. In our paper we proposed a combinatorial rule for merging estimated and/or calculated values for all known sources of error, to yield a single overall predicted accuracy for the machine. In this paper we compare our original predictions with measured performance of the completed instrument.

  19. Lessons from Two Years of Building Fusion Ignition Targets with the Precision Robotic Assembly Machine

    SciTech Connect

    Montesanti, R C; Alger, E T; Atherton, L J; Bhandarkar, S D; Castro, C; Dzenitis, E G; Hamza, A V; Klingmann, J L; Nikroo, A; Parham, T G; Reynolds, J L; Seugling, R M; Swisher, M F; Taylor, J S; Witte, M C

    2010-02-19

    The Precision Robotic Assembly Machine was developed to manufacture the small and intricate laser-driven fusion ignition targets that are being used in the world's largest and most energetic laser, the National Ignition Facility (NIF). The National Ignition Campaign (NIC) goal of using the NIF to produce a self-sustaining nuclear fusion burn with energy gain - for the first time ever in a laboratory setting - requires targets that are demanding in materials fabrication, machining, and assembly. We provide an overview of the design and function of the machine, with emphasis on the aspects that revolutionized how NIC targets are manufactured.

  20. Design and verification of an ultra-precision 3D-coordinate measuring machine with parallel drives

    NASA Astrophysics Data System (ADS)

    Bos, Edwin; Moers, Ton; van Riel, Martijn

    2015-08-01

    An ultra-precision 3D coordinate measuring machine (CMM), the TriNano N100, has been developed. In our design, the workpiece is mounted on a 3D stage, which is driven by three parallel drives that are mutually orthogonal. The linear drives support the 3D stage using vacuum preloaded (VPL) air bearings, whereby each drive determines the position of the 3D stage along one translation direction only. An exactly constrained design results in highly repeatable machine behavior. Furthermore, the machine complies with the Abbé principle over its full measurement range and the application of parallel drives allows for excellent dynamic behavior. The design allows a 3D measurement uncertainty of 100 nanometers in a measurement range of 200 cubic centimeters. Verification measurements using a Gannen XP 3D tactile probing system on a spherical artifact show a standard deviation in single point repeatability of around 2 nm in each direction.

  1. Precision Machining and Technology; Machine Shop Work--Advanced: 9557.04.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    The course outline has been prepared as a guide to assist the instructor in systematically planning and presenting a variety of meaningful lessons to facilitate the necessary training for the machine shop student. The material is designed to enable the student to learn the manipulative skills and related knowledge necessary to understand the jig…

  2. Ontological modelling of knowledge management for human-machine integrated design of ultra-precision grinding machine

    NASA Astrophysics Data System (ADS)

    Hong, Haibo; Yin, Yuehong; Chen, Xing

    2016-11-01

    Despite the rapid development of computer science and information technology, an efficient human-machine integrated enterprise information system for designing complex mechatronic products is still not fully accomplished, partly because of the inharmonious communication among collaborators. Therefore, one challenge in human-machine integration is how to establish an appropriate knowledge management (KM) model to support integration and sharing of heterogeneous product knowledge. Aiming at the diversity of design knowledge, this article proposes an ontology-based model to reach an unambiguous and normative representation of knowledge. First, an ontology-based human-machine integrated design framework is described, then corresponding ontologies and sub-ontologies are established according to different purposes and scopes. Second, a similarity calculation-based ontology integration method composed of ontology mapping and ontology merging is introduced. The ontology searching-based knowledge sharing method is then developed. Finally, a case of human-machine integrated design of a large ultra-precision grinding machine is used to demonstrate the effectiveness of the method.

  3. Engineering, Trade, and Technical Cluster. Task Analyses. Drafting and Design Technology, Precision Machining Technology, Electronics Technology.

    ERIC Educational Resources Information Center

    Henrico County Public Schools, Glen Allen, VA. Virginia Vocational Curriculum and Resource Center.

    Developed in Virginia, this publication contains task analysis guides to support selected tech prep programs that prepare students for careers in the engineering, trade, and technical cluster. Three occupations are profiled: drafting and design technology, precision machining technology, and electronics technology. Each guide contains the…

  4. Machine learning applications in genetics and genomics.

    PubMed

    Libbrecht, Maxwell W; Noble, William Stafford

    2015-06-01

    The field of machine learning, which aims to develop computer algorithms that improve with experience, holds promise to enable computers to assist humans in the analysis of large, complex data sets. Here, we provide an overview of machine learning applications for the analysis of genome sequencing data sets, including the annotation of sequence elements and epigenetic, proteomic or metabolomic data. We present considerations and recurrent challenges in the application of supervised, semi-supervised and unsupervised machine learning methods, as well as of generative and discriminative modelling approaches. We provide general guidelines to assist in the selection of these machine learning methods and their practical application for the analysis of genetic and genomic data sets. PMID:25948244

  5. Machine learning applications in genetics and genomics.

    PubMed

    Libbrecht, Maxwell W; Noble, William Stafford

    2015-06-01

    The field of machine learning, which aims to develop computer algorithms that improve with experience, holds promise to enable computers to assist humans in the analysis of large, complex data sets. Here, we provide an overview of machine learning applications for the analysis of genome sequencing data sets, including the annotation of sequence elements and epigenetic, proteomic or metabolomic data. We present considerations and recurrent challenges in the application of supervised, semi-supervised and unsupervised machine learning methods, as well as of generative and discriminative modelling approaches. We provide general guidelines to assist in the selection of these machine learning methods and their practical application for the analysis of genetic and genomic data sets.

  6. Precise Applications Of The Global Positioning System

    NASA Technical Reports Server (NTRS)

    Lichten, Stephen M.

    1992-01-01

    Report represents overview of Global Positioning System (GPS). Emphasizes those aspects of theory, history, and status of GPS pertaining to potential utility for highly precise scientific measurements. Current and anticipated applications include measurements of crustal motions in seismically active regions of Earth, measurements of rate of rotation of Earth and orientation of poles, tracking of non-GPS spacecraft in orbit around Earth, surveying, measurements of radio-signal-propagation delays, determinations of coordinates of ground stations, and transfer of precise time signals worldwide.

  7. Machine intelligence for robotics applications

    SciTech Connect

    Weisbin, C.R.; Barhen, J.; de Saussure, G.; Hamel, W.R.; Jorgensen, C.; Oblow, E.M.; Ricks, R.E.

    1985-01-01

    The purpose of this paper is to review research in machine intelligence ongoing at the Center for Engineering Systems Advanced Research (CESAR). As a result of initial experimentation with our HERMIES-I mobile robot, hardware and software upgrades were implemented which enable fully asynchronous sonar operation, improved stepper motor control for the sensory platform, and more reliable wheel drive control. The current system, designated as HERMIES-II, is discussed. Successful demonstration of dead-reckoning navigation and the development of a sensor-based exploration and discovery algorithm which can now handle typical maze problems are reported. The development of HERMIES ''brain'' as a hypercube ensemble machine with concurrent computation and associated message passing is described. Algorithms for mapping precedence-constrained task graphs onto a hypercube yield results with high efficiency and proper load balance. A framework for a hybrid uncertainty analysis theory for decision making is described.

  8. A real-time surface inspection system for precision steel balls based on machine vision

    NASA Astrophysics Data System (ADS)

    Chen, Yi-Ji; Tsai, Jhy-Cherng; Hsu, Ya-Chen

    2016-07-01

    Precision steel balls are one of the most fundament components for motion and power transmission parts and they are widely used in industrial machinery and the automotive industry. As precision balls are crucial for the quality of these products, there is an urgent need to develop a fast and robust system for inspecting defects of precision steel balls. In this paper, a real-time system for inspecting surface defects of precision steel balls is developed based on machine vision. The developed system integrates a dual-lighting system, an unfolding mechanism and inspection algorithms for real-time signal processing and defect detection. The developed system is tested under feeding speeds of 4 pcs s-1 with a detection rate of 99.94% and an error rate of 0.10%. The minimum detectable surface flaw area is 0.01 mm2, which meets the requirement for inspecting ISO grade 100 precision steel balls.

  9. A real-time surface inspection system for precision steel balls based on machine vision

    NASA Astrophysics Data System (ADS)

    Chen, Yi-Ji; Tsai, Jhy-Cherng; Hsu, Ya-Chen

    2016-07-01

    Precision steel balls are one of the most fundament components for motion and power transmission parts and they are widely used in industrial machinery and the automotive industry. As precision balls are crucial for the quality of these products, there is an urgent need to develop a fast and robust system for inspecting defects of precision steel balls. In this paper, a real-time system for inspecting surface defects of precision steel balls is developed based on machine vision. The developed system integrates a dual-lighting system, an unfolding mechanism and inspection algorithms for real-time signal processing and defect detection. The developed system is tested under feeding speeds of 4 pcs s‑1 with a detection rate of 99.94% and an error rate of 0.10%. The minimum detectable surface flaw area is 0.01 mm2, which meets the requirement for inspecting ISO grade 100 precision steel balls.

  10. Machine Learning for Biological Trajectory Classification Applications

    NASA Technical Reports Server (NTRS)

    Sbalzarini, Ivo F.; Theriot, Julie; Koumoutsakos, Petros

    2002-01-01

    Machine-learning techniques, including clustering algorithms, support vector machines and hidden Markov models, are applied to the task of classifying trajectories of moving keratocyte cells. The different algorithms axe compared to each other as well as to expert and non-expert test persons, using concepts from signal-detection theory. The algorithms performed very well as compared to humans, suggesting a robust tool for trajectory classification in biological applications.

  11. Apparatus for correcting precision errors in slide straightness in machine tools

    DOEpatents

    Robinson, Samuel C.; Gerth, Howard L.

    1981-01-01

    The present invention is directed to a mechanism by which small deviations in slideway straightness and roll of a precision machining apparatus may be compensated for. The mechanism of the present invention comprises a fixture support disposed between the slideway carriage and the tool or workpiece fixture and provided with a hinge-like coupling between the carriage and the fixture support so as to allow for the minute and precise displacement of the fixture support in a direction normal to the direction of the slide path so as to readily compensate for slight deviations in the straightness and roll of the slide path.

  12. Apparatus for correcting precision errors in slide straigntness in machine tools

    DOEpatents

    Robinson, S.C.; Gerth, H.L.

    The present invention is directed to a mechanism by which small deviations in slideway straightness and roll of a precision machining apparatus may be compensated for. The mechanism of the present invention comprises a fixture support disposed between the slideway carriage and the tool or workpiece fixture and provided with a hinge-like coupling between the carriage and the fixture support so as to allow for the minute and precise displacement of the fixture support in a direction normal to the direction of the slide path soa as to readily compensate for slight deviations in the straightness and roll of the slide path.

  13. Precision visual guidance for agricultural applicator aircraft

    NASA Astrophysics Data System (ADS)

    Hartt, Joseph R.; Bletzacker, Frank R.; Forgette, T. J.; Vetter, Alan A.

    1992-07-01

    The in-cockpit swath centerline identifier (SCI) for aerial applicators uses differentially corrected global positioning system (GPS) signals to determine precise ground track of an aircraft and provide guidance to the pilot for flying patterns for aerial application of materials such as pesticides, herbicides, and fertilizers. Cross track distance from the swath centerline is provided by a heads up light bar display while detailed navigation, position, and status information is provided on an alphanumeric display on a panel mounted console. This system provides straight line guidance when executing a swath and turn-in guidance when proceeding from one swath to the next. It provides a record of the swaths which were sprayed and logs all of the associated navigation and operational data, including time. In addition, it provides navigation information from base to the fields, between fields, and return. The SCI eliminates the need for flaggers while providing improved accuracy of application. Reduced exposure to liability and improved quality control results as the position, altitude, time, and spray status are logged for post flight analysis. The SCI has been used in commercial agricultural applications. Demonstrations of the SCI showed better precision than anticipated.

  14. Precise on-machine extraction of the surface normal vector using an eddy current sensor array

    NASA Astrophysics Data System (ADS)

    Wang, Yongqing; Lian, Meng; Liu, Haibo; Ying, Yangwei; Sheng, Xianjun

    2016-11-01

    To satisfy the requirements of on-machine measurement of the surface normal during complex surface manufacturing, a highly robust normal vector extraction method using an Eddy current (EC) displacement sensor array is developed, the output of which is almost unaffected by surface brightness, machining coolant and environmental noise. A precise normal vector extraction model based on a triangular-distributed EC sensor array is first established. Calibration of the effects of object surface inclination and coupling interference on measurement results, and the relative position of EC sensors, is involved. A novel apparatus employing three EC sensors and a force transducer was designed, which can be easily integrated into the computer numerical control (CNC) machine tool spindle and/or robot terminal execution. Finally, to test the validity and practicability of the proposed method, typical experiments were conducted with specified testing pieces using the developed approach and system, such as an inclined plane and cylindrical and spherical surfaces.

  15. KrF excimer laser precision machining of hard and brittle ceramic biomaterials.

    PubMed

    Huang, Yao-Xiong; Lu, Jian-Yi; Huang, Jin-Xia

    2014-06-01

    KrF excimer laser precision machining of porous hard-brittle ceramic biomaterials was studied to find a suitable way of machining the materials into various desired shapes and sizes without distorting their intrinsic structure and porosity. Calcium phosphate glass ceramics (CPGs) and hydroxyapatite (HA) were chosen for the study. It was found that KrF excimer laser can cut both CPGs and HA with high efficiency and precision. The ablation rates of CPGs and HA are respectively 0.081 µm/(pulse J cm(-2)) and 0.048 µm/(pulse  J cm(-2)), while their threshold fluences are individually 0.72 and 1.5 J cm(-2). The cutting quality (smoothness of the cut surface) is a function of laser repetition rate and cutting speed. The higher the repetition rate and lower the cutting speed, the better the cutting quality. A comparison between the cross sections of CPGs and HA cut using the excimer laser and using a conventional diamond cutting blade indicates that those cut by the excimer laser could retain their intrinsic porosity and geometry without distortion. In contrast, those cut by conventional machining had distorted geometry and most of their surface porosities were lost. Therefore, when cutting hard-brittle ceramic biomaterials to prepare scaffold and implant or when sectioning them for porosity evaluation, it is better to choose KrF excimer laser machining.

  16. KrF excimer laser precision machining of hard and brittle ceramic biomaterials.

    PubMed

    Huang, Yao-Xiong; Lu, Jian-Yi; Huang, Jin-Xia

    2014-06-01

    KrF excimer laser precision machining of porous hard-brittle ceramic biomaterials was studied to find a suitable way of machining the materials into various desired shapes and sizes without distorting their intrinsic structure and porosity. Calcium phosphate glass ceramics (CPGs) and hydroxyapatite (HA) were chosen for the study. It was found that KrF excimer laser can cut both CPGs and HA with high efficiency and precision. The ablation rates of CPGs and HA are respectively 0.081 µm/(pulse J cm(-2)) and 0.048 µm/(pulse  J cm(-2)), while their threshold fluences are individually 0.72 and 1.5 J cm(-2). The cutting quality (smoothness of the cut surface) is a function of laser repetition rate and cutting speed. The higher the repetition rate and lower the cutting speed, the better the cutting quality. A comparison between the cross sections of CPGs and HA cut using the excimer laser and using a conventional diamond cutting blade indicates that those cut by the excimer laser could retain their intrinsic porosity and geometry without distortion. In contrast, those cut by conventional machining had distorted geometry and most of their surface porosities were lost. Therefore, when cutting hard-brittle ceramic biomaterials to prepare scaffold and implant or when sectioning them for porosity evaluation, it is better to choose KrF excimer laser machining. PMID:24784833

  17. Status of the Development of Beryllium-Copper Alloy Ignition Capsules by Precision Machining

    NASA Astrophysics Data System (ADS)

    Nobile, Arthur

    2005-10-01

    Cu-doped Be capsules are being developed for ignition on the National Ignition Facility (NIF). The fabrication approach being pursued at Los Alamos is based on bonding of cylindrical parts containing precision machined hemispherical cavities, followed by machining the external contour to produce a spherical capsule. While we have demonstrated this approach, there are several key issues that need to be resolved before a capsule meeting NIF specifications can be produced. These issues are synthesis of high purity small grain size Be-Cu alloy, formation of a hemishell bond strong enough to allow the capsule to be machined after the hemishells are bonded, precision machining and polishing of the capsule to meet stringent specifications for surface finish and spherical quality, and filling with DT. In this paper we report on the progress that has been made on these issues. This work is performed at Los Alamos National Laboratory and supported by U.S. Department of Energy under contract number W7405-ENG36

  18. Ultra precision machining technique of off-axis optics for coastal water remote sensing

    NASA Astrophysics Data System (ADS)

    Jeon, Min-Woo; Hyun, Sang-Won; Han, Jeong-Yeol; Kim, Geon-Hee

    2015-10-01

    An off-axis optical system can effectively avoid some problems, such as aberrations, shielded area created by the secondary mirror and a narrow field of view (FOV), while an on-axis optical system has the problems. Inspired by the consideration, the off-axis optical system is generally used for hyperspectral sensors and telescopes. However, there are several obstacles limiting the productivity of the off-axis optics in fabrication and measurement processes. In this study, to overcome this weakness, we suggests a new fabrication technique using a customized jig, not separated from the work-piece. A convex aspheric mirror and the off-axis mirror are fabricated by Single Point Diamond Turning Machine (SPDTM) for comparison analysis of surface state. The mirrors are made from aluminum (Al6061-T6) and used for the reflectors of a coastal water remote sensing system. We show fast machining and simple measurement in comparison with traditional off-axis single machining and measurement, provide performance results, such as form accuracy and surface roughness measured by both contact 3D profilometer (UA3P) and non-contact 3D profiler (CCI-Optics). The customized ultra-precision machining process can be effectively used for complex off-axis mirror fabricating.

  19. Precision machining and polishing of scintillating crystals for large calorimeters and hodoscopes

    NASA Astrophysics Data System (ADS)

    Wuest, C. R.; Fuchs, B. A.; Holdener, F. R.; Heck, J. L., Jr.

    1994-04-01

    New machining and polishing techniques have been developed for large scintillating crystal arrays such as the Barium Fluoride Electromagnetic Calorimeter for the GEM Detector at SSCL, the Crystal Clear Collaboration's cerium fluoride or lead tungstenate calorimeter at the proposed LHC and CERN, the PHENIX Detector at RHIC (barium fluoride), and the cesium iodide Calorimeter for the BaBar Detector at PEP-2 B Factory at SLAC. The machining and polishing methods to be presented in this paper provide crystalline surfaces without sub-surface damage or deformation as verified by Rutherford Back-scattering (RBS) analysis. Surface roughness of about 10-20 A and sub-micron mechanical tolerances have been demonstrated on large barium fluoride crystal samples. Mass production techniques have also been developed for machining the proper angled surfaces and polishing up to five 50 cm long crystals at one time. These techniques utilize kinematic mount technology developed at LLNL to allow precision machining and polishing of complex surfaces. They will present this technology along with detailed surface studies of barium fluoride and cerium fluoride crystals polished with this technique.

  20. Multiscale Modeling and Analysis of an Ultra-Precision Damage Free Machining Method

    NASA Astrophysics Data System (ADS)

    Guan, Chaoliang; Peng, Wenqiang

    2016-06-01

    Under the condition of high laser flux, laser induced damage of optical element does not occur is the key to success of laser fusion ignition system. US government survey showed that the processing defects caused the laser induced damage threshold (LIDT) to decrease is one of the three major challenges. Cracks and scratches caused by brittle and plastic removal machining are fatal flaws. Using hydrodynamic effect polishing method can obtain damage free surface on quartz glass. The material removal mechanism of this typical ultra-precision machining process was modeled in multiscale. In atomic scale, chemical modeling illustrated the weakening and breaking of chemical bond energy. In particle scale, micro contact modeling given the elastic remove mode boundary of materials. In slurry scale, hydrodynamic flow modeling showed the dynamic pressure and shear stress distribution which are relations with machining effect. Experiment was conducted on a numerically controlled system, and one quartz glass optical component was polished in the elastic mode. Results show that the damages are removed away layer by layer as the removal depth increases due to the high damage free machining ability of the HEP. And the LIDT of sample was greatly improved.

  1. Multiagent cooperative systems applied to precision applications

    NASA Astrophysics Data System (ADS)

    McKay, Mark D.; Anderson, Matthew O.; Gunderson, Robert W.; Flann, Nicholas S.; Abbott, Ben A.

    1998-08-01

    Regulatory agencies are imposing limits and constraints to protect the operator and/or the environment. While generally necessary, these controls also tend to increase cost and decrease efficiency and productivity. Intelligent computer systems can be made to perform these hazardous tasks with greater efficiency and precision without danger to the operators. The Idaho National Engineering and Environmental Laboratory and the Center for Self-Organizing and Intelligent Systems at Utah State University have developed a series of autonomous all-terrain multi-agent systems capable of performing automated tasks within hazardous environments. This pare discusses the development and application of cooperative small-scale and large-scale robots for use in various activities associated with radiologically contaminated areas, prescription farming, and unexploded ordinances.

  2. Development of a machine vision system for a real-time precision sprayer

    NASA Astrophysics Data System (ADS)

    Bossu, Jérémie; Gée, Christelle; Truchetet, Frédéric

    2007-01-01

    In the context of precision agriculture, we have developed a machine vision system for a real time precision sprayer. From a monochrome CCD camera located in front of the tractor, the discrimination between crop and weeds is obtained with an image processing based on spatial information using a Gabor filter. This method allows to detect the periodic signals from the non periodic one and it enables to enhance the crop rows whereas weeds have patchy distribution. Thus, weed patches were clearly identified by a blob-coloring method. Finally, we use a pinhole model to transform the weed patch coordinates image in world coordinates in order to activate the right electro-pneumatic valve of the sprayer at the right moment.

  3. Design and Optimization of Ultrasonic Vibration Mechanism using PZT for Precision Laser Machining

    NASA Astrophysics Data System (ADS)

    Kim, Woo-Jin; Lu, Fei; Cho, Sung-Hak; Park, Jong-Kweon; Lee, Moon G.

    As the aged population grows around the world, many medical instruments and devices have been developed recently. Among the devices, a drug delivery stent is a medical device which requires precision machining. Conventional drug delivery stent has problems of residual polymer and decoating because the drug is coated on the surface of stent with the polymer. If the drug is impregnated in the micro sized holes on the surface, the problems can be overcome because there is no need to use the polymer anymore. Micro sized holes are generally fabricated by laser machining; however, the fabricated holes do not have a high aspect ratio or a good surface finish. To overcome these problems, we propose a vibration-assisted machining mechanism with PZT (Piezoelectric Transducers) for the fabrication of micro sized holes. If the mechanism vibrates the eyepiece of the laser machining head, the laser spot on the workpiece will vibrate vertically because objective lens in the eyepiece shakes by the mechanism's vibration. According to the former researches, the vibrating frequency over 20 kHz and amplitude over 500 nm are preferable. The vibration mechanism has cylindrical guide, hollowed PZT and supports. In the cylinder, the eyepiece is mounted. The cylindrical guide has upper and low plates and side wall. The shape of plates and side wall are designed to have high resonating frequency and large amplitude of motion. The PZT is also selected to have high actuating force and high speed of motion. The support has symmetrical and rigid configuration. The mechanism secures linear motion of the eyepiece. This research includes sensitivity analysis and design of ultrasonic vibration mechanism. As a result of design, the requirements of high frequency and large amplitude are achieved.

  4. Precision aerial application for site-specific rice crop management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Precision agriculture includes different technologies that allow agricultural professional to use information management tools to optimize agriculture production. The new technologies allow aerial application applicators to improve application accuracy and efficiency, which saves time and money for...

  5. Laboratory directed research and development final report: Intelligent tools for on-machine acceptance of precision machined components

    SciTech Connect

    Christensen, N.G.; Harwell, L.D.; Hazelton, A.

    1997-02-01

    On-Machine Acceptance (OMA) is an agile manufacturing concept being developed for machine tools at SNL. The concept behind OMA is the integration of product design, fabrication, and qualification processes by using the machining center as a fabrication and inspection tool. This report documents the final results of a Laboratory Directed Research and Development effort to qualify OMA.

  6. High energy green nanosecond and picosecond pulse delivery through a negative curvature fiber for precision micro-machining.

    PubMed

    Jaworski, Piotr; Yu, Fei; Carter, Richard M; Knight, Jonathan C; Shephard, Jonathan D; Hand, Duncan P

    2015-04-01

    In this paper we present an anti-resonant guiding, low-loss Negative Curvature Fiber (NCF) for the efficient delivery of high energy short (ns) and ultrashort (ps) pulsed laser light in the green spectral region. The fabricated NCF has an attenuation of 0.15 dB/m and 0.18 dB/m at 532 nm and 515 nm respectively, and provided robust transmission of nanosecond and picosecond pulses with energies of 0.57 mJ (10.4 kW peak power) and 30 µJ (5 MW peak power) respectively. It provides single-mode, stable (low bend-sensitivity) output and maintains spectral and temporal properties of the source laser beam. The practical application of fiber-delivered pulses has been demonstrated in precision micro-machining and marking of metals and glass.

  7. Web Mining: Machine Learning for Web Applications.

    ERIC Educational Resources Information Center

    Chen, Hsinchun; Chau, Michael

    2004-01-01

    Presents an overview of machine learning research and reviews methods used for evaluating machine learning systems. Ways that machine-learning algorithms were used in traditional information retrieval systems in the "pre-Web" era are described, and the field of Web mining and how machine learning has been used in different Web mining applications…

  8. Data Collection Satellite Application in Precision Agriculture

    NASA Astrophysics Data System (ADS)

    Durào, O.

    2002-01-01

    's over Brazilian territory. There were 25 platforms when SCD-1 was launched. However this number is growing rapidly to 400 platforms, at first for measurements of water reservoir levels as well as other hydrology applications (The Brazilian Electricity Regulatory Agency - ANEEL is the customer), and for many other different applications such as meteorology, oceanography, environmental monitoring sciences, and people and animal tracking. The clear feeling is that users are discovering a satellite system whose benefits were not previously well understood when launched and being able to propose and come up with different and useful applications. A new field in the country that has a great potential to benefit from this system is agriculture. Per se, this is a very important sector of the Brazilian economy and its international trade. Combining it with space technology may justify the investment of new and low cost dedicated satellites. This paper describes a new proposal for use of the SCD-1,2,CBERS-1 satellite system for precision agriculture. New PCD's would be developed for measurements of chemical content of the soil, such as, for example, Nitrogen and others, beyond humidity and solar incidence. This can lead to a more efficient fertilization, harvesting and even the spray of chemical defensives, with the consequence of environment protection. The PCD's ground network so established, along with the information network already available, combined with the space segment of such a system may, as previously said, be able to justify the investment in low cost satellites with this sole purpose.

  9. Precision machining of optical surfaces with subaperture correction technologies MRF and IBF

    NASA Astrophysics Data System (ADS)

    Schmelzer, Olaf; Feldkamp, Roman

    2015-10-01

    Precision optical elements are used in a wide range of technical instrumentations. Many optical systems e.g. semiconductor inspection modules, laser heads for laser material processing or high end movie cameras, contain precision optics even aspherical or freeform surfaces. Critical parameters for such systems are wavefront error, image field curvature or scattered light. Following these demands the lens parameters are also critical concerning power and RMSi of the surface form error and micro roughness. How can we reach these requirements? The emphasis of this discussion is set on the application of subaperture correction technologies in the fabrication of high-end aspheres and free-forms. The presentation focuses on the technology chain necessary for the production of high-precision aspherical optical components and the characterization of the applied subaperture finishing tools MRF (magneto-rheological finishing) and IBF (ion beam figuring). These technologies open up the possibility of improving the performance of optical systems.

  10. High precision applications of the global positioning system

    NASA Technical Reports Server (NTRS)

    Lichten, Stephen M.

    1991-01-01

    The Global Positioning System (GPS) is a constellation of U.S. defense navigation satellites which can be used for military and civilian positioning applications. A wide variety of GPS scientific applications were identified and precise positioning capabilities with GPS were already demonstrated with data available from the present partial satellite constellation. Expected applications include: measurements of Earth crustal motion, particularly in seismically active regions; measurements of the Earth's rotation rate and pole orientation; high-precision Earth orbiter tracking; surveying; measurements of media propagation delays for calibration of deep space radiometric data in support of NASA planetary missions; determination of precise ground station coordinates; and precise time transfer worldwide.

  11. Backward smoothing for precise GNSS applications

    NASA Astrophysics Data System (ADS)

    Vaclavovic, Pavel; Dousa, Jan

    2015-10-01

    The Extended Kalman filter is widely used for its robustness and simple implementation. Parameters estimated for solving dynamical systems usually require certain time to converge and need to be smoothed by a dedicated algorithms. The purpose of our study was to implement smoothing algorithms for processing both code and carrier phase observations with Precise Point Positioning method. We implemented and used the well known Rauch-Tung-Striebel smoother (RTS). It has been found out that the RTS suffer from significant numerical instability in smoothed state covariance matrix determination. We improved the processing with algorithms based on Singular Value Decomposition, which was more robust. Observations from many permanent stations have been processed with final orbits and clocks provided by the International GNSS service (IGS), and the smoothing improved stability and precision in every cases. Moreover, (re)convergence of the parameters were always successfully eliminated.

  12. Machine intelligence applications to securities production

    SciTech Connect

    Johnson, C.K.

    1987-01-01

    The production of security documents provides a cache of interesting problems ranging across a broad spectrum. Some of the problems do not have rigorous scientific solutions available at this time and provide opportunities for less structured approaches such as AI. AI methods can be used in conjunction with traditional scientific and computational methods. The most productive applications of AI occur when this marriage of methods can be carried out without motivation to prove that one method is better than the other. Fields such as ink chemistry and technology, and machine inspection of graphic arts printing offer interesting challenges which will continue to intrigue current and future generations of researchers into the 21st century.

  13. [Application of precision medicine in the field of surgery].

    PubMed

    Deng, Aiwen; Xiong, Ribo; Zeng, Canjun

    2015-11-01

    Precision medicine, based on personalized medicine, is to provide personalized and precise treatment. The emergence of 3D printing technique as well as genome sequencing provides an effective way to realize precise and personalized treatment. The application of 3D printing technique in the field of surgery is listed as following: optimize operation plan to achieve precise and personalized surgery; design personalized navigation template; personalized prosthesis production; design of personalized tissue and organ. With the development of tissue engineering, new material technology and genome sequencing and the improvement in related polices and regulations, precision medicine will step on a higher level in the field of surgery. This review introduces the application of precision medicine in the field of surgery.

  14. [Application of precision medicine in the field of surgery].

    PubMed

    Deng, Aiwen; Xiong, Ribo; Zeng, Canjun

    2015-11-01

    Precision medicine, based on personalized medicine, is to provide personalized and precise treatment. The emergence of 3D printing technique as well as genome sequencing provides an effective way to realize precise and personalized treatment. The application of 3D printing technique in the field of surgery is listed as following: optimize operation plan to achieve precise and personalized surgery; design personalized navigation template; personalized prosthesis production; design of personalized tissue and organ. With the development of tissue engineering, new material technology and genome sequencing and the improvement in related polices and regulations, precision medicine will step on a higher level in the field of surgery. This review introduces the application of precision medicine in the field of surgery. PMID:26607096

  15. Developing Ubiquitous Sensor Network Platform Using Internet of Things: Application in Precision Agriculture

    PubMed Central

    Ferrández-Pastor, Francisco Javier; García-Chamizo, Juan Manuel; Nieto-Hidalgo, Mario; Mora-Pascual, Jerónimo; Mora-Martínez, José

    2016-01-01

    The application of Information Technologies into Precision Agriculture methods has clear benefits. Precision Agriculture optimises production efficiency, increases quality, minimises environmental impact and reduces the use of resources (energy, water); however, there are different barriers that have delayed its wide development. Some of these main barriers are expensive equipment, the difficulty to operate and maintain and the standard for sensor networks are still under development. Nowadays, new technological development in embedded devices (hardware and communication protocols), the evolution of Internet technologies (Internet of Things) and ubiquitous computing (Ubiquitous Sensor Networks) allow developing less expensive systems, easier to control, install and maintain, using standard protocols with low-power consumption. This work develops and test a low-cost sensor/actuator network platform, based in Internet of Things, integrating machine-to-machine and human-machine-interface protocols. Edge computing uses this multi-protocol approach to develop control processes on Precision Agriculture scenarios. A greenhouse with hydroponic crop production was developed and tested using Ubiquitous Sensor Network monitoring and edge control on Internet of Things paradigm. The experimental results showed that the Internet technologies and Smart Object Communication Patterns can be combined to encourage development of Precision Agriculture. They demonstrated added benefits (cost, energy, smart developing, acceptance by agricultural specialists) when a project is launched. PMID:27455265

  16. Developing Ubiquitous Sensor Network Platform Using Internet of Things: Application in Precision Agriculture.

    PubMed

    Ferrández-Pastor, Francisco Javier; García-Chamizo, Juan Manuel; Nieto-Hidalgo, Mario; Mora-Pascual, Jerónimo; Mora-Martínez, José

    2016-07-22

    The application of Information Technologies into Precision Agriculture methods has clear benefits. Precision Agriculture optimises production efficiency, increases quality, minimises environmental impact and reduces the use of resources (energy, water); however, there are different barriers that have delayed its wide development. Some of these main barriers are expensive equipment, the difficulty to operate and maintain and the standard for sensor networks are still under development. Nowadays, new technological development in embedded devices (hardware and communication protocols), the evolution of Internet technologies (Internet of Things) and ubiquitous computing (Ubiquitous Sensor Networks) allow developing less expensive systems, easier to control, install and maintain, using standard protocols with low-power consumption. This work develops and test a low-cost sensor/actuator network platform, based in Internet of Things, integrating machine-to-machine and human-machine-interface protocols. Edge computing uses this multi-protocol approach to develop control processes on Precision Agriculture scenarios. A greenhouse with hydroponic crop production was developed and tested using Ubiquitous Sensor Network monitoring and edge control on Internet of Things paradigm. The experimental results showed that the Internet technologies and Smart Object Communication Patterns can be combined to encourage development of Precision Agriculture. They demonstrated added benefits (cost, energy, smart developing, acceptance by agricultural specialists) when a project is launched.

  17. Developing Ubiquitous Sensor Network Platform Using Internet of Things: Application in Precision Agriculture.

    PubMed

    Ferrández-Pastor, Francisco Javier; García-Chamizo, Juan Manuel; Nieto-Hidalgo, Mario; Mora-Pascual, Jerónimo; Mora-Martínez, José

    2016-01-01

    The application of Information Technologies into Precision Agriculture methods has clear benefits. Precision Agriculture optimises production efficiency, increases quality, minimises environmental impact and reduces the use of resources (energy, water); however, there are different barriers that have delayed its wide development. Some of these main barriers are expensive equipment, the difficulty to operate and maintain and the standard for sensor networks are still under development. Nowadays, new technological development in embedded devices (hardware and communication protocols), the evolution of Internet technologies (Internet of Things) and ubiquitous computing (Ubiquitous Sensor Networks) allow developing less expensive systems, easier to control, install and maintain, using standard protocols with low-power consumption. This work develops and test a low-cost sensor/actuator network platform, based in Internet of Things, integrating machine-to-machine and human-machine-interface protocols. Edge computing uses this multi-protocol approach to develop control processes on Precision Agriculture scenarios. A greenhouse with hydroponic crop production was developed and tested using Ubiquitous Sensor Network monitoring and edge control on Internet of Things paradigm. The experimental results showed that the Internet technologies and Smart Object Communication Patterns can be combined to encourage development of Precision Agriculture. They demonstrated added benefits (cost, energy, smart developing, acceptance by agricultural specialists) when a project is launched. PMID:27455265

  18. Application of PLC in digitization control intelligence can-body high-speed resitance welding machine

    NASA Astrophysics Data System (ADS)

    Chen, Shaobo; Zhang, Ziqiang; Yan, Qiusheng; Zheng, Zhidan; Li, Yang; Zhang, Tianyu

    2003-09-01

    The application of position servo synchronously tracking system constituted with PLC and general AC servo system in digitalization control intelligence can-body high-speed resistance welding machine is introduced in this paper. By studying the digitalization control system of automatic can-body resistance welding machine, technologic upgrade of product is made, and application of PLC in controlling general AC servo motor multi-axes ganged system to replace conventional mechanical ganged mechanism is developed. It makes the coordination of movements between machine actions can be ensured and every correlative actions can quickly and precisely run synchronously, quondam mechanical branching driving can be replaced, and "mechanical locking" between quondam movements can be changed to the "electronic locking," complex mechanical structures such as cams, stepless speed changing machines and universal joints and so on can be omitted, so the working capability of whole machine can effectively be enhanced and synchronization between the machine actions can rapidly be reached. The application realizes digitalization process control, enhances reliability, stability and manufacturing efficiency of the machine, and reduces the manufacturing cost.

  19. Modeling of Energy Transfer for Carbon Nanotube-Based Precision Machining

    NASA Astrophysics Data System (ADS)

    Wong, Basil T.; Pinar Menguc, M.; Vallance, R. Ryan; Rao, Apparao M.

    2003-03-01

    INTRODUCTION Possible use of electron emission from carbon nanotubes (CNTs) for precision machining has been realized only recently. It is hypothesized that by coupling CNT electron emission with radiation transfer mechanism nano-scaled machining can be achieved. A laser, for example, can be used to raise the temperature of the workpiece near its melting point, and a carbon nanotube is then used to transfer additional energy required to the workpiece to complete the removal of minute amount of materials for nanomachining process. To investigate this hypothesis, a detailed numerical/analytical study is conducted. Electron transfer is modeled using a Monte Carlo approach, and a detailed radiation transfer model, including Fresnel reflections is adapted. Based on the numerical simulations we found that a power of one-tenth of a watt is required from a CNT alone to raise the temperature of gold beyond its melting point. However, using a localized heating with a laser, the required power can be reduced by roughly more than a half. This paper outlines the details of the numerical simulation and establishes a set of design guidelines for future nanomachining modalities. We are interested in nanomachining using the CNTs. Our objective is to determine if we can effectively remove tens of atoms from the workpiece by electron transfer from a single CNT and proper laser heating from either side of the workpiece. To reach our goal, energy transfer from a single CNT may not be sufficient. One way to overcome this setback is to preheat the workpiece to a certain temperature through a bulk heating, and using a subsequent localized heating by the laser beam to further increase the temperature of a specified location. Thus only a minimum amount of energy is required from the nanotube to process the material, i.e. to remove tens of atoms. Due to the complicated interactions between propagating electrons and the solid material, obtaining a physically realistic theoretical analysis

  20. Adaptive Machining Of Large, Somewhat Flexible Parts

    NASA Technical Reports Server (NTRS)

    Gutow, David; Wagner, Garrett; Gilbert, Jeffrey L.; Deily, David

    1996-01-01

    Adaptive machining is method of machining large, somewhat flexible workpieces to close tolerances. Devised for machining precise weld lands on aft skirts of rocket nozzles, but underlying concept generally applicable to precise machining of any of large variety of workpieces deformed by thermal, gravitational, and/or machining forces. For example, in principle, method used to bore precise hole on unanchored end of long cantilever beam.

  1. Applications of Remote Sensing to Precision Agriculture

    NASA Astrophysics Data System (ADS)

    Seielstad, G. A.; Laguette, S.; Seelan, S.; Lawrence, R.; Henry, M.; Maynard, C.; Dalsted, K.; Rattling Leaf, J.

    2001-05-01

    The Upper Midwest Aerospace Consortium (UMAC) has changed agricultural practices in the following ways: (1) farmers and ranchers have become partners with, not clients of, researchers; (2) experiments are carried out in the field rather than on small experimental plots; (3) the field is considered an agro-ecosystem, with all the complexities of multiple interactions, rather than attempting to isolate certain parameters and vary only a few; (4) both economic benefit to the producer and sound environmental stewardship for society are achievable. This approach has revealed that information is as significant an input to farm or ranch management as seeds, fertilizers, irrigation, and tillage. Accurate, timely information equips producers with the ability to make decisions during a growing season that optimize the yield at harvest time. An invaluable source of in-season information is imagery acquired from sensors on satellites or aircraft. In addition to sensing reflected sunlight in wavebands outside the visible, remote sensing's overview also reveals anomalous patterns in the vegetation cover that are difficult to spot on the ground. Anomalies can be caused by weeds, disease, water stress, inadequate nutrients, or other causes. Often, anomalies must be detected early or they spread too quickly to be addressed. The paper will demonstrate how remote sensing has been applied to (1) define management zones in farm fields, (2) prescribe variable rate applications of fertilizer, (3) detect pest infestations, and (4) manage cattle grazing according to forage available. The applications were possible because data were processed within 4-5 days of acquisition by the satellite, and then delivered by high-bandwidth satellite links to farmers, ranchers, and tribal government officials in minimal transit time. The applications research described was part of NASA's Synergy Program.

  2. Laser applications in machining slab materials

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoping

    1990-10-01

    Since the invention of the laser back in 1960, laser technology has been extensively applied in many fields of science and technology. These has been a history of nearly two decades of using lasers as an energy source in machining materials, such as cutting, welding, ruling and boring, among other operations. With the development of flexible automation in production, the advantages of laser machining have has grown more and more obvious. The combination of laser technology and computer science further promotes the enhancement and upgrading of laser machining and related equipment. At present, many countries are building high quality laser equipment for machining slab materials, such as the Coherent and Spectra Physics corporations in the United States, the Trumpf Corporation in West Germany, the Amada Corporation in Japan, and the Bystronic Corporation in Switzerland, among other companies.

  3. Precise Head Tracking in Hearing Applications

    NASA Astrophysics Data System (ADS)

    Helle, A. M.; Pilinski, J.; Luhmann, T.

    2015-05-01

    The paper gives an overview about two research projects, both dealing with optical head tracking in hearing applications. As part of the project "Development of a real-time low-cost tracking system for medical and audiological problems (ELCoT)" a cost-effective single camera 3D tracking system has been developed which enables the detection of arm and head movements of human patients. Amongst others, the measuring system is designed for a new hearing test (based on the "Mainzer Kindertisch"), which analyzes the directional hearing capabilities of children in cooperation with the research project ERKI (Evaluation of acoustic sound source localization for children). As part of the research project framework "Hearing in everyday life (HALLO)" a stereo tracking system is being used for analyzing the head movement of human patients during complex acoustic events. Together with the consideration of biosignals like skin conductance the speech comprehension and listening effort of persons with reduced hearing ability, especially in situations with background noise, is evaluated. For both projects the system design, accuracy aspects and results of practical tests are discussed.

  4. The application of unmanned aerial vehicle to precision agriculture: Chlorophyll, nitrogen, and evapotranspiration estimation

    NASA Astrophysics Data System (ADS)

    Elarab, Manal

    Precision agriculture (PA) is an integration of a set of technologies aiming to improve productivity and profitability while sustaining the quality of the surrounding environment. It is a process that vastly relies on high-resolution information to enable greater precision in the management of inputs to production. This dissertation explored the usage of multispectral high resolution aerial imagery acquired by an unmanned aerial systems (UAS) platform to serve precision agriculture application. The UAS acquired imagery in the visual, near infrared and thermal infrared spectra with a resolution of less than a meter (15--60 cm). This research focused on developing two models to estimate cm-scale chlorophyll content and leaf nitrogen. To achieve the estimations a well-established machine learning algorithm (relevance vector machine) was used. The two models were trained on a dataset of in situ collected leaf chlorophyll and leaf nitrogen measurements, and the machine learning algorithm intelligently selected the most appropriate bands and indices for building regressions with the highest prediction accuracy. In addition, this research explored the usage of the high resolution imagery to estimate crop evapotranspiration (ET) at 15 cm resolution. A comparison was also made between the high resolution ET and Landsat derived ET over two different crop cover (field crops and vineyards) to assess the advantages of UAS based high resolution ET. This research aimed to bridge the information embedded in the high resolution imagery with ground crop parameters to provide site specific information to assist farmers adopting precision agriculture. The framework of this dissertation consisted of three components that provide tools to support precision agriculture operational decisions. In general, the results for each of the methods developed were satisfactory, relevant, and encouraging.

  5. A study on ultra-precision machining technique for Al6061-T6 to fabricate space infrared optics

    NASA Astrophysics Data System (ADS)

    Ryu, Geun-man; Lee, Gil-jae; Hyun, Sang-won; Sung, Ha-yeong; Chung, Euisik; Kim, Geon-hee

    2014-08-01

    In this paper, analysis of variance on designed experiments with full factorial design was applied to determine the optimized machining parameters for ultra-precision fabrication of the secondary aspheric mirror, which is one of the key elements of the space cryogenic infrared optics. A single point diamond turning machine (SPDTM, Nanotech 4μpL Moore) was adopted to fabricate the material, AL6061-T6, and the three machining parameters of cutting speed, feed rate and depth of cut were selected. With several randomly assigned experimental conditions, surface roughness of each condition was measured by a non-contact optical profiler (NT2000; Vecco). As a result of analysis using Minitab, the optimum cutting condition was determined as following; cutting speed: 122 m/min, feed rate: 3 mm/min and depth of cut: 1 μm. Finally, a 120 mm diameter aspheric secondary mirror was attached to a particularly designed jig by using mixture of paraffin and wax and successfully fabricated under the optimum machining parameters. The profile of machined surface was measured by a high-accuracy 3-D profilometer(UA3P; Panasonic) and we obtained the geometrical errors of 30.6 nm(RMS) and 262.4 nm(PV), which satisfy the requirements of the space cryogenic infrared optics.

  6. Remote machine engineering applications for nuclear facilities decommissioning

    SciTech Connect

    Toto, G.; Wyle, H.R.

    1983-01-01

    Decontamination and decommissioning of a nuclear facility require the application of techniques that protect the worker and the enviroment from radiological contamination and radiation. Remotely operated portable robotic arms, machines, and devices can be applied. The use of advanced systems should enhance the productivity, safety, and cost facets of the efforts; remote automatic tooling and systems may be used on any job where job hazard and other factors justify application. Many problems based on costs, enviromental impact, health, waste generation, and political issues may be mitigated by use of remotely operated machines. The work that man can not do or should not do will have to be done by machines.

  7. Estimating chlorophyll with thermal and broadband multispectral high resolution imagery from an unmanned aerial system using relevance vector machines for precision agriculture

    NASA Astrophysics Data System (ADS)

    Elarab, Manal; Ticlavilca, Andres M.; Torres-Rua, Alfonso F.; Maslova, Inga; McKee, Mac

    2015-12-01

    Precision agriculture requires high-resolution information to enable greater precision in the management of inputs to production. Actionable information about crop and field status must be acquired at high spatial resolution and at a temporal frequency appropriate for timely responses. In this study, high spatial resolution imagery was obtained through the use of a small, unmanned aerial system called AggieAirTM. Simultaneously with the AggieAir flights, intensive ground sampling for plant chlorophyll was conducted at precisely determined locations. This study reports the application of a relevance vector machine coupled with cross validation and backward elimination to a dataset composed of reflectance from high-resolution multi-spectral imagery (VIS-NIR), thermal infrared imagery, and vegetative indices, in conjunction with in situ SPAD measurements from which chlorophyll concentrations were derived, to estimate chlorophyll concentration from remotely sensed data at 15-cm resolution. The results indicate that a relevance vector machine with a thin plate spline kernel type and kernel width of 5.4, having LAI, NDVI, thermal and red bands as the selected set of inputs, can be used to spatially estimate chlorophyll concentration with a root-mean-squared-error of 5.31 μg cm-2, efficiency of 0.76, and 9 relevance vectors.

  8. Precision biopolymers from protein precursors for biomedical applications.

    PubMed

    Kuan, Seah Ling; Wu, Yuzhou; Weil, Tanja

    2013-03-12

    The synthesis of biohybrid materials with tailored functional properties represents a topic of emerging interest. Combining proteins as natural, macromolecular building blocks, and synthetic polymers opens access to giant brush-like biopolymers of high structural definition. The properties of these precision polypeptide copolymers can be tailored through various chemical modifications along their polypeptide backbone, which expands the repertoire of known protein-based materials to address biomedical applications. In this article, the synthetic strategies for the design of precision biopolymers from proteins through amino acid specific conjugation reagents are highlighted and the different functionalization strategies, their characterization, and applications are discussed.

  9. An autonomous multisensor in situ metrology system for enabling high dynamic range measurement of 3D surfaces on precision machine tools

    NASA Astrophysics Data System (ADS)

    Liu, Samuel M. Y.; Cheung, Benny C. F.; Whitehouse, David; Cheng, Ching-Hsiang

    2016-11-01

    An in situ measurement is of prime importance when trying to maintain the position of the workpiece for further compensation processes in order to improve the accuracy and efficiency of the precision machining of three dimensional (3D) surfaces. However, the coordinates of most of the machine tools with closed machine interfaces and control system are not accessible for users, which make it difficult to use the motion axes of the machine tool for in situ measurements. This paper presents an autonomous multisensor in situ metrology system for enabling high dynamic range measurement of 3D surfaces on precision machine tools. It makes use of a designed tool path and an additional motion sensor to assist the registration of time-space data for the position estimation of a 2D laser scanner which measures the surface with a high lateral resolution and large area without the need to interface with the machine tool system. A prototype system was built and integrated into an ultra-precision polishing machine. Experimental results show that it measures the 3D surfaces with high resolution, high repeatability, and large measurement range. The system not only improves the efficiency and accuracy of the precision machining process but also extends the capability of machine tools.

  10. Remote sensing with unmanned aircraft systems for precision agriculture applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Federal Aviation Administration is revising regulations for using unmanned aircraft systems (UAS) in the national airspace. An important potential application of UAS may be as a remote-sensing platform for precision agriculture, but simply down-scaling remote sensing methodologies developed usi...

  11. In pursuit of precision: the calibration of minds and machines in late nineteenth-century psychology.

    PubMed

    Benschop, R; Draaisma, D

    2000-01-01

    A prominent feature of late nineteenth-century psychology was its intense preoccupation with precision. Precision was at once an ideal and an argument: the quest for precision helped psychology to establish its status as a mature science, sharing a characteristic concern with the natural sciences. We will analyse how psychologists set out to produce precision in 'mental chronometry', the measurement of the duration of psychological processes. In his Leipzig laboratory, Wundt inaugurated an elaborate research programme on mental chronometry. We will look at the problem of calibration of experimental apparatus and will describe the intricate material, literary, and social technologies involved in the manufacture of precision. First, we shall discuss some of the technical problems involved in the measurement of ever shorter time-spans. Next, the Cattell-Berger experiments will help us to argue against the received view that all the precision went into the hardware, and practically none into the social organization of experimentation. Experimenters made deliberate efforts to bring themselves and their subjects under a regime of control and calibration similar to that which reigned over the experimental machinery. In Leipzig psychology, the particular blend of material and social technology resulted in a specific object of study: the generalized mind. We will then show that the distribution of precision in experimental psychology outside Leipzig demanded a concerted effort of instruments, texts, and people. It will appear that the forceful attempts to produce precision and uniformity had some rather paradoxical consequences. PMID:11624166

  12. Precision engineering for optical applications: knowledge transfer into UK industry

    NASA Astrophysics Data System (ADS)

    Sansom, Christopher; Shore, Paul

    2009-06-01

    A means of facilitating the transfer of precision engineering knowledge and skills from academic institutions and their research partners into UK optics and optical engineering companies is described. The process involves the creation of an Integrated Knowledge Centre (IKC), a partnership led by Cranfield University with the support of the University of Cambridge, University College London, and the OpTIC technium. This paper describes the development of the three main vehicles for knowledge transfer. These are a Masters level postgraduate degree course (the Cranfield University led MSc in "Ultra Precision Technologies"), a portfolio of industrial short courses which are designed to address key skills shortages in the fields of precision engineering for optical applications, and an e-learning package in precision engineering. The main issues encountered during the development of the knowledge transfer teaching and learning packages are discussed, and the outcomes from the first year of knowledge transfer activities are described. In overall summary, the results demonstrate how the Integrated Knowledge Centre in Ultra Precision and Structured Surfaces' approach to knowledge transfer has been effective in addressing the engineering skills gap in precision optics based industries.

  13. On-machine laser triangulation sensor for precise surface displacement measurement of various material types

    NASA Astrophysics Data System (ADS)

    Žbontar, Klemen; Podobnik, Boštjan; Povše, Franc; Mihelj, Matjaž

    2013-09-01

    The paper presents a custom-designed laser triangulation based metrology system, which enables high precision surface displacement measurement of various material types with a single sensor configuration. Laser structuring applications require material surface alignment relative to the laser focus position where fabrication conditions are optimal. The measurement system utilizes a high-quality UV wavelength laser beam (primarily used for structuring purposes) with automatic control of its intensity. The laser source operates in a continuous wave (CW) mode during the measurement process, whereas the UV wavelength enables measurement of transparent materials. Robust displacement measurement of various material types was solved by introducing a new approach of structured light projection and its centroid detection. A high resolution 2D galvanometric scanning system is used for dynamic symmetrical pattern projection, which is proven to reduce the effects of material surface related errors and speckle noise. Furthermore, a "double curve fitting" (DCF) centroid detection algorithm, where Gaussian curves are fitted to radial cross sections of the acquired pattern, and an ellipse is fitted to their peak positions, was introduced. The method includes subsurface scattering compensation, which proves crucial for translucent material measurement, where incident light penetrates into the material surface and causes uneven light intensity distribution of the acquired pattern. Experimental results have shown that the metrology system is robust to laser intensity variation and material type, with measurement bias lower than 50 μm and standard deviation lower than +/-6.3 μm for all materials. The developed probe has been integrated into commercial LPKF laser structuring systems.

  14. Time-optimized laser micro machining by using a new high dynamic and high precision galvo scanner

    NASA Astrophysics Data System (ADS)

    Jaeggi, Beat; Neuenschwander, Beat; Zimmermann, Markus; Zecherle, Markus; Boeckler, Ernst W.

    2016-03-01

    High accuracy, quality and throughput are key factors in laser micro machining. To obtain these goals the ablation process, the machining strategy and the scanning device have to be optimized. The precision is influenced by the accuracy of the galvo scanner and can further be enhanced by synchronizing the movement of the mirrors with the laser pulse train. To maintain a high machining quality i.e. minimum surface roughness, the pulse-to-pulse distance has also to be optimized. Highest ablation efficiency is obtained by choosing the proper laser peak fluence together with highest specific removal rate. The throughput can now be enhanced by simultaneously increasing the average power, the repetition rate as well as the scanning speed to preserve the fluence and the pulse-to-pulse distance. Therefore a high scanning speed is of essential importance. To guarantee the required excellent accuracy even at high scanning speeds a new interferometry based encoder technology was used, that provides a high quality signal for closed-loop control of the galvo scanner position. Low inertia encoder design enables a very dynamic scanner system, which can be driven to very high line speeds by a specially adapted control solution. We will present results with marking speeds up to 25 m/s using a f = 100 mm objective obtained with a new scanning system and scanner tuning maintaining a precision of about 5 μm. Further it will be shown that, especially for short line lengths, the machining time can be minimized by choosing the proper speed which has not to be the maximum one.

  15. Precision Machining. FasTrak Specialization Integrated Technical and Academic Competency (ITAC). 2002 Revision.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Div. of Career-Technical and Adult Education.

    This publication provided the competencies and key indicators for a program that enables students to prepare for a number of occupations within the broader metalworking industry. Specializations include machinist, computer numerical control programmers, and maintenance and machine builders. Competencies and the related key indicators are presented…

  16. Engineering Artificial Machines from Designable DNA Materials for Biomedical Applications

    PubMed Central

    Huang, Guoyou; Han, Yulong; Zhang, Xiaohui; Li, Yuhui; Pingguan-Murphy, Belinda; Lu, Tian Jian; Xu, Feng

    2015-01-01

    Deoxyribonucleic acid (DNA) emerges as building bricks for the fabrication of nanostructure with complete artificial architecture and geometry. The amazing ability of DNA in building two- and three-dimensional structures raises the possibility of developing smart nanomachines with versatile controllability for various applications. Here, we overviewed the recent progresses in engineering DNA machines for specific bioengineering and biomedical applications. PMID:25547514

  17. Engineering artificial machines from designable DNA materials for biomedical applications.

    PubMed

    Qi, Hao; Huang, Guoyou; Han, Yulong; Zhang, Xiaohui; Li, Yuhui; Pingguan-Murphy, Belinda; Lu, Tian Jian; Xu, Feng; Wang, Lin

    2015-06-01

    Deoxyribonucleic acid (DNA) emerges as building bricks for the fabrication of nanostructure with complete artificial architecture and geometry. The amazing ability of DNA in building two- and three-dimensional structures raises the possibility of developing smart nanomachines with versatile controllability for various applications. Here, we overviewed the recent progresses in engineering DNA machines for specific bioengineering and biomedical applications.

  18. Machine vision application in animal trajectory tracking.

    PubMed

    Koniar, Dušan; Hargaš, Libor; Loncová, Zuzana; Duchoň, František; Beňo, Peter

    2016-04-01

    This article was motivated by the doctors' demand to make a technical support in pathologies of gastrointestinal tract research [10], which would be based on machine vision tools. Proposed solution should be less expensive alternative to already existing RF (radio frequency) methods. The objective of whole experiment was to evaluate the amount of animal motion dependent on degree of pathology (gastric ulcer). In the theoretical part of the article, several methods of animal trajectory tracking are presented: two differential methods based on background subtraction, the thresholding methods based on global and local threshold and the last method used for animal tracking was the color matching with a chosen template containing a searched spectrum of colors. The methods were tested offline on five video samples. Each sample contained situation with moving guinea pig locked in a cage under various lighting conditions. PMID:26776540

  19. Machine vision for high-precision volume measurement applied to levitated containerless material processing

    SciTech Connect

    Bradshaw, R.C.; Schmidt, D.P.; Rogers, J.R.; Kelton, K.F.; Hyers, R.W.

    2005-12-15

    By combining the best practices in optical dilatometry with numerical methods, a high-speed and high-precision technique has been developed to measure the volume of levitated, containerlessly processed samples with subpixel resolution. Containerless processing provides the ability to study highly reactive materials without the possibility of contamination affecting thermophysical properties. Levitation is a common technique used to isolate a sample as it is being processed. Noncontact optical measurement of thermophysical properties is very important as traditional measuring methods cannot be used. Modern, digitally recorded images require advanced numerical routines to recover the subpixel locations of sample edges and, in turn, produce high-precision measurements.

  20. Machine Vision for High Precision Volume Measurement Applied to Levitated Containerless Materials Processing

    NASA Technical Reports Server (NTRS)

    Bradshaw, R. C.; Schmidt, D. P.; Rogers, J. R.; Kelton, K. F.; Hyers, R. W.

    2005-01-01

    By combining the best practices in optical dilatometry with new numerical methods, a high-speed and high precision technique has been developed to measure volume of levitated, containerlessly processed samples with sub- pixel resolution. Containerless processing provides the ability to study highly reactive materials without the possibility of contamination affecting thermo-physical properties. Levitation is a common technique used to isolate a sample as it is being processed. Noncontact optical measurement of thermo-ophysical properties is very important as traditional measuring methods cannot be used. Modern, digitally recorded images require advanced numerical routines to recover the sub-pixel locations of sample edges and, in turn produce high precision measurements.

  1. Applications of Support Vector Machines In Chemo And Bioinformatics

    NASA Astrophysics Data System (ADS)

    Jayaraman, V. K.; Sundararajan, V.

    2010-10-01

    Conventional linear & nonlinear tools for classification, regression & data driven modeling are being replaced on a rapid scale by newer techniques & tools based on artificial intelligence and machine learning. While the linear techniques are not applicable for inherently nonlinear problems, newer methods serve as attractive alternatives for solving real life problems. Support Vector Machine (SVM) classifiers are a set of universal feed-forward network based classification algorithms that have been formulated from statistical learning theory and structural risk minimization principle. SVM regression closely follows the classification methodology. In this work recent applications of SVM in Chemo & Bioinformatics will be described with suitable illustrative examples.

  2. Software architecture for time-constrained machine vision applications

    NASA Astrophysics Data System (ADS)

    Usamentiaga, Rubén; Molleda, Julio; García, Daniel F.; Bulnes, Francisco G.

    2013-01-01

    Real-time image and video processing applications require skilled architects, and recent trends in the hardware platform make the design and implementation of these applications increasingly complex. Many frameworks and libraries have been proposed or commercialized to simplify the design and tuning of real-time image processing applications. However, they tend to lack flexibility, because they are normally oriented toward particular types of applications, or they impose specific data processing models such as the pipeline. Other issues include large memory footprints, difficulty for reuse, and inefficient execution on multicore processors. We present a novel software architecture for time-constrained machine vision applications that addresses these issues. The architecture is divided into three layers. The platform abstraction layer provides a high-level application programming interface for the rest of the architecture. The messaging layer provides a message-passing interface based on a dynamic publish/subscribe pattern. A topic-based filtering in which messages are published to topics is used to route the messages from the publishers to the subscribers interested in a particular type of message. The application layer provides a repository for reusable application modules designed for machine vision applications. These modules, which include acquisition, visualization, communication, user interface, and data processing, take advantage of the power of well-known libraries such as OpenCV, Intel IPP, or CUDA. Finally, the proposed architecture is applied to a real machine vision application: a jam detector for steel pickling lines.

  3. Calculation of the performance of magnetic lenses with limited machining precision.

    PubMed

    Sháněl, O; Zlámal, J; Oral, M

    2014-02-01

    To meet a required STEM resolution, the mechanical precision of the pole pieces of a magnetic lens needs to be determined. A tolerancing plugin in the EOD software is used to determine a configuration which both meets the optical specifications and is cost effective under the constraints of current manufacturing technologies together with a suitable combination of correction elements.

  4. A Novel Transverse Flux Machine for Vehicle Traction Applications

    SciTech Connect

    Wan, Zhao; Ahmed, Adeeb; Husain, Iqbal; Muljadi, Eduard

    2015-10-05

    A novel transverse flux machine topology for electric vehicle traction application using ferrite magnets is presented in this paper. The proposed transverse flux topology utilizes novel magnet arrangements in the rotor that are similar to Halbach-array to boost flux linkage; on the stator side, cores are alternately arranged around a pair of ring windings in each phase to make use of the entire rotor flux that eliminates end windings. Analytical design considerations and finite element methods are used for an optimized design of a scooter in-wheel motor. Simulation results from Finite Element Analysis (FEA) show the motor achieved comparable torque density to conventional rare-earth permanent magnet machines. This machine is a viable candidate for direct drive applications with low cost and high torque density.

  5. Novel Transverse Flux Machine for Vehicle Traction Applications: Preprint

    SciTech Connect

    Wan, Z.; Ahmed, A.; Husain, I.; Muljadi, E.

    2015-04-02

    A novel transverse flux machine topology for electric vehicle traction applications using ferrite magnets is presented in this paper. The proposed transverse flux topology utilizes novel magnet arrangements in the rotor that are similar to the Halbach array to boost flux linkage; on the stator side, cores are alternately arranged around a pair of ring windings in each phase to make use of the entire rotor flux that eliminates end windings. Analytical design considerations and finite-element methods are used for an optimized design of a scooter in-wheel motor. Simulation results from finite element analysis (FEA) show that the motor achieved comparable torque density to conventional rare-earth permanent magnet (PM) machines. This machine is a viable candidate for direct-drive applications with low cost and high torque density.

  6. Applications of high power lasers. [using reflection holograms for machining and surface treatment

    NASA Technical Reports Server (NTRS)

    Angus, J. C.

    1979-01-01

    The use of computer generated, reflection holograms in conjunction with high power lasers for precision machining of metals and ceramics was investigated. The Reflection holograms which were developed and made to work at both optical wavelength (He-Ne, 6328 A) and infrared (CO2, 10.6) meet the primary practical requirement of ruggedness and are relatively economical and simple to fabricate. The technology is sufficiently advanced now so that reflection holography could indeed be used as a practical manufacturing device in certain applications requiring low power densities. However, the present holograms are energy inefficient and much of the laser power is lost in the zero order spot and higher diffraction orders. Improvements of laser machining over conventional methods are discussed and addition applications are listed. Possible uses in the electronics industry include drilling holes in printed circuit boards making soldered connections, and resistor trimming.

  7. Evaluation of a high-precision gear measuring machine for helix measurement using helix and wedge artifacts

    NASA Astrophysics Data System (ADS)

    Taguchi, Tetsuya; Kondo, Yohan

    2016-08-01

    High-precision gears are required for advanced motion and power transmission. The reliability of the measured value becomes important as the gear accuracy increases, and the establishment of a traceability system is needed. Therefore, a high-precision gear measuring machine (GMM) with a smaller uncertainty is expected to improve the gear calibration uncertainty. For this purpose, we developed a prototype of a high-precision GMM that adopts a direct drive mechanism and other features. Then, the high measurement capability of the developed GMM was verified using gear artifacts. Recently, some new measurement methods using simple shapes such as spheres and planes have been proposed as standards. We have verified the tooth profile measurement using a sphere artifact and reported the results that the developed GMM had a high capability in tooth profile measurement. Therefore, we attempted to devise a new evaluation method for helix measurement using a wedge artifact (WA) whose plane was treated as the tooth flank, and the high measurement capability of the developed GMM was verified. The results will provide a part of information to fully assess measurement uncertainty as our future work. This paper describes the evaluation results of the developed GMM for helix measurement using both a helix artifact and the WA, and discusses the effectiveness of the WA as a new artifact to evaluate the GMMs.

  8. Generation of gear tooth surfaces by application of CNC machines

    NASA Technical Reports Server (NTRS)

    Litvin, F. L.; Chen, N. X.

    1994-01-01

    This study will demonstrate the importance of application of computer numerically controlled (CNC) machines in generation of gear tooth surfaces with new topology. This topology decreases gear vibration and will extend the gear capacity and service life. A preliminary investigation by a tooth contact analysis (TCA) program has shown that gear tooth surfaces in line contact (for instance, involute helical gears with parallel axes, worm gear drives with cylindrical worms, etc.) are very sensitive to angular errors of misalignment that cause edge contact and an unfavorable shape of transmission errors and vibration. The new topology of gear tooth surfaces is based on the localization of bearing contact, and the synthesis of a predesigned parabolic function of transmission errors that is able to absorb a piecewise linear function of transmission errors caused by gear misalignment. The report will describe the following topics: description of kinematics of CNC machines with six degrees of freedom that can be applied for generation of gear tooth surfaces with new topology. A new method for grinding of gear tooth surfaces by a cone surface or surface of revolution based on application of CNC machines is described. This method provides an optimal approximation of the ground surface to the given one. This method is especially beneficial when undeveloped ruled surfaces are to be ground. Execution of motions of the CNC machine is also described. The solution to this problem can be applied as well for the transfer of machine tool settings from a conventional generator to the CNC machine. The developed theory required the derivation of a modified equation of meshing based on application of the concept of space curves, space curves represented on surfaces, geodesic curvature, surface torsion, etc. Condensed information on these topics of differential geometry is provided as well.

  9. Application of an On-machine Gage for Diameter Measurements

    NASA Technical Reports Server (NTRS)

    Harding, Kevin G.

    1993-01-01

    This paper describes the design analysis and application of a laser based gage made specifically for measuring parts on the machine tool to a high accuracy. The tri-beam gage uses three beams of light to measure the local curvature of the part in a manner similar to a V-block gage. The properties of this design include: calibration that is independent of the machine tool scales, non-contact damage free operation, low cost of the gage, and the ability to measure parts in motion.

  10. [The Application of Machine Perfusion on Clinical Liver Transplantation].

    PubMed

    Ren, Fenggang; Zhu, Haoyang; Yan, Xiaopeng; Liu, Chang; Zhang, Xiaogang; Lv, Yi

    2015-11-01

    Liver transplantation is the only way to treat end-stage liver disease. In order to overcome the shortage of donor, marginal donors have been used widely, which bring about a series of problems. Machine perfusion can stimulate the circulation in vivo and is beneficial for the protection of liver. It could also improve the graft function and reduce postoperative complications, which makes it a hot spot in recent years. The aim of this study is to summarize the current status and prospects of application of machine perfusion on clinical liver transplantation.

  11. The evolution and practical application of machine translation system (2)

    NASA Astrophysics Data System (ADS)

    Tominaga, Isao; Nakagawa, Tsuyoshi; Shimizu, Hideko; Sato, Masayuki

    This paper described development and practical application J-E machine translation system in JICST. The relation between machine translation system and JICST File Compiling & Editing System, practice of pre-editing and post-editing, performance and evaluation of system, the cost etc. were introduced. In comparison with the human translation, the benefit is not recognized as turnaround time. However, it is about a half as the cost. If translation accuracy improves, turnaround time and the cost will be improved further. This paper described translation service of full paper, construction of a translation network as a conception in future of machine translation system. This English abstract was made using Mu system. Pre-editing and post-editing is not used.

  12. Precise time and time interval applications to electric power systems

    NASA Technical Reports Server (NTRS)

    Wilson, Robert E.

    1992-01-01

    There are many applications of precise time and time interval (frequency) in operating modern electric power systems. Many generators and customer loads are operated in parallel. The reliable transfer of electrical power to the consumer partly depends on measuring power system frequency consistently in many locations. The internal oscillators in the widely dispersed frequency measuring units must be syntonized. Elaborate protection and control systems guard the high voltage equipment from short and open circuits. For the highest reliability of electric service, engineers need to study all control system operations. Precise timekeeping networks aid in the analysis of power system operations by synchronizing the clocks on recording instruments. Utility engineers want to reproduce events that caused loss of service to customers. Precise timekeeping networks can synchronize protective relay test-sets. For dependable electrical service, all generators and large motors must remain close to speed synchronism. The stable response of a power system to perturbations is critical to continuity of electrical service. Research shows that measurement of the power system state vector can aid in the monitoring and control of system stability. If power system operators know that a lightning storm is approaching a critical transmission line or transformer, they can modify operating strategies. Knowledge of the location of a short circuit fault can speed the re-energizing of a transmission line. One fault location technique requires clocks synchronized to one microsecond. Current research seeks to find out if one microsecond timekeeping can aid and improve power system control and operation.

  13. Application of Hollow Sphere Structures and Composites in Processing Machines

    NASA Astrophysics Data System (ADS)

    Schöler, Martin; Mauermann, Marc; Majschak, Jens-Peter

    The term processing machines refers to a large variety of machines and equipment for the mass production of consumer goods. Processing machines are often specially tailored according to the particular processing task they have to fulfill, such as pasteurising milk or packing goods. Furthermore the vast majority is characterised by large production outputs, demanding high processing velocities and fast moving parts. A special application is that of the food and drug processing area. Due to high quality standards there are special requirements for material surfaces to be considered if surfaces are in contact with the manufactured product. This chapter deals with the special demands concerning dedicated engineering materials that occur from state of the art processing machines. Specific requirements ranging from high damping abilities for support components to high stiffness and low weight for fast moving tools are presented by means of a general classification of processing machines into four functional areas. Accordingly, the proposed hollow sphere structures and similar material classes are presented and applied on each of these four areas.

  14. Precision measurements and applications of femtosecond frequency combs

    NASA Astrophysics Data System (ADS)

    Jones, R. Jason

    2002-05-01

    The merging of femtosecond (fs) laser physics with the field of optical f requency metrology over recent years has had a profound impact on both di sciplines. Precision control of the broad frequency bandwidth from fs la sers has enabled new areas of exploration in ultrafast physics and revolu tionized optical frequency measurement and precision spectroscopy. Most recently, the transition frequency of the length standard at 514.7 nm,^ 127I2 P(13) 43-0 a3 has been measured in our lab with an improvement of more than 100 times in precision. Interesting molecular dynamics and s tructure are being explored using absolute frequency map of molecular tra nsitions over a large wavelength range. The iodine transition at 532 nm h as been used to establish an optical atomic clock with a fs comb providin g both an RF standard with stability comparable to the best atomic clocks and millions of optical frequencies across the visible and near IR spect rum, each stable to the Hz level. Work is presently underway to directly compare the iodine optical clocks at JILA with the Hg and Ca optical cloc ks currently being refined at NIST via a direct optical fiber link. A wi dely tunable single frequency laser in combination with a fs comb has bee n employed to realize an optical frequency synthesizer. Frequency combs of two independent ultrafast lasers have been coherently locked, enablin g several different avenues of application such as synthesis of arbitrary waveforms, coherent control of quantum systems, and coherent anti-Stokes Raman scattering microscopy. This talk will review these recent accompl ishments from our lab and discuss plans for further improving the control and precision of fs laser based measurements. te

  15. A fast and precise indoor localization algorithm based on an online sequential extreme learning machine.

    PubMed

    Zou, Han; Lu, Xiaoxuan; Jiang, Hao; Xie, Lihua

    2015-01-01

    Nowadays, developing indoor positioning systems (IPSs) has become an attractive research topic due to the increasing demands on location-based service (LBS) in indoor environments. WiFi technology has been studied and explored to provide indoor positioning service for years in view of the wide deployment and availability of existing WiFi infrastructures in indoor environments. A large body of WiFi-based IPSs adopt fingerprinting approaches for localization. However, these IPSs suffer from two major problems: the intensive costs of manpower and time for offline site survey and the inflexibility to environmental dynamics. In this paper, we propose an indoor localization algorithm based on an online sequential extreme learning machine (OS-ELM) to address the above problems accordingly. The fast learning speed of OS-ELM can reduce the time and manpower costs for the offline site survey. Meanwhile, its online sequential learning ability enables the proposed localization algorithm to adapt in a timely manner to environmental dynamics. Experiments under specific environmental changes, such as variations of occupancy distribution and events of opening or closing of doors, are conducted to evaluate the performance of OS-ELM. The simulation and experimental results show that the proposed localization algorithm can provide higher localization accuracy than traditional approaches, due to its fast adaptation to various environmental dynamics. PMID:25599427

  16. A Fast and Precise Indoor Localization Algorithm Based on an Online Sequential Extreme Learning Machine

    PubMed Central

    Zou, Han; Lu, Xiaoxuan; Jiang, Hao; Xie, Lihua

    2015-01-01

    Nowadays, developing indoor positioning systems (IPSs) has become an attractive research topic due to the increasing demands on location-based service (LBS) in indoor environments. WiFi technology has been studied and explored to provide indoor positioning service for years in view of the wide deployment and availability of existing WiFi infrastructures in indoor environments. A large body of WiFi-based IPSs adopt fingerprinting approaches for localization. However, these IPSs suffer from two major problems: the intensive costs of manpower and time for offline site survey and the inflexibility to environmental dynamics. In this paper, we propose an indoor localization algorithm based on an online sequential extreme learning machine (OS-ELM) to address the above problems accordingly. The fast learning speed of OS-ELM can reduce the time and manpower costs for the offline site survey. Meanwhile, its online sequential learning ability enables the proposed localization algorithm to adapt in a timely manner to environmental dynamics. Experiments under specific environmental changes, such as variations of occupancy distribution and events of opening or closing of doors, are conducted to evaluate the performance of OS-ELM. The simulation and experimental results show that the proposed localization algorithm can provide higher localization accuracy than traditional approaches, due to its fast adaptation to various environmental dynamics. PMID:25599427

  17. A fast and precise indoor localization algorithm based on an online sequential extreme learning machine.

    PubMed

    Zou, Han; Lu, Xiaoxuan; Jiang, Hao; Xie, Lihua

    2015-01-15

    Nowadays, developing indoor positioning systems (IPSs) has become an attractive research topic due to the increasing demands on location-based service (LBS) in indoor environments. WiFi technology has been studied and explored to provide indoor positioning service for years in view of the wide deployment and availability of existing WiFi infrastructures in indoor environments. A large body of WiFi-based IPSs adopt fingerprinting approaches for localization. However, these IPSs suffer from two major problems: the intensive costs of manpower and time for offline site survey and the inflexibility to environmental dynamics. In this paper, we propose an indoor localization algorithm based on an online sequential extreme learning machine (OS-ELM) to address the above problems accordingly. The fast learning speed of OS-ELM can reduce the time and manpower costs for the offline site survey. Meanwhile, its online sequential learning ability enables the proposed localization algorithm to adapt in a timely manner to environmental dynamics. Experiments under specific environmental changes, such as variations of occupancy distribution and events of opening or closing of doors, are conducted to evaluate the performance of OS-ELM. The simulation and experimental results show that the proposed localization algorithm can provide higher localization accuracy than traditional approaches, due to its fast adaptation to various environmental dynamics.

  18. Application of Smart Infrastructure Systems approach to precision medicine

    PubMed Central

    Govindaraju, Diddahally R.; Annaswamy, Anuradha M.

    2015-01-01

    All biological variation is hierarchically organized dynamic network system of genomic components, organelles, cells, tissues, organs, individuals, families, populations and metapopulations. Individuals are axial in this hierarchy, as they represent antecedent, attendant and anticipated aspects of health, disease, evolution and medical care. Humans show individual specific genetic and clinical features such as complexity, cooperation, resilience, robustness, vulnerability, self-organization, latent and emergent behavior during their development, growth and senescence. Accurate collection, measurement, organization and analyses of individual specific data, embedded at all stratified levels of biological, demographic and cultural diversity – the big data – is necessary to make informed decisions on health, disease and longevity; which is a central theme of precision medicine initiative (PMI). This initiative also calls for the development of novel analytical approaches to handle complex multidimensional data. Here we suggest the application of Smart Infrastructure Systems (SIS) approach to accomplish some of the goals set forth by the PMI on the premise that biological systems and the SIS share many common features. The latter has been successfully employed in managing complex networks of non-linear adaptive controls, commonly encountered in smart engineering systems. We highlight their concordance and discuss the utility of the SIS approach in precision medicine programs. PMID:27054084

  19. Multi-agent cooperative systems applied to precision applications

    SciTech Connect

    McKay, M.D.; Anderson, M.O.; Gunderson, R.W.; Flann, N.; Abbott, B.

    1998-03-01

    Regulatory agencies are imposing limits and constraints to protect the operator and/or the environment. While generally necessary, these controls also tend to increase cost and decrease efficiency and productivity. Intelligent computer systems can be made to perform these hazardous tasks with greater efficiency and precision without danger to the operators. The Idaho national Engineering and Environmental Laboratory and the Center for Self-Organizing and Intelligent Systems at Utah State University have developed a series of autonomous all-terrain multi-agent systems capable of performing automated tasks within hazardous environments. This paper discusses the development and application of cooperative small-scale and large-scale robots for use in various activities associated with radiologically contaminated areas, prescription farming, and unexploded ordinances.

  20. Design of gas bearing systems for precision applications

    NASA Astrophysics Data System (ADS)

    Wang, Junming

    Research to provide the up to date knowledge and efficient tools to design better Externally Pressurized Gas (EPG) bearing systems, including the design of individual bearings, and to arrange all the bearings used in an optimal way is reported. Both circular and rectangular EPG pads with rigid bearing surfaces and rigid inlet restrictors were used. The following topics closely related to the applications in precision engineering are discussed: influences of gap shape on the bearing performance; effects of bearing body tilt on the bearing performance; influences of bearing surface imperfections on bearing performance; temperature drops in EPG bearings in quasistationary conditions; the optimal use of multiple bearings in a mechanical system; the use of EPG bearing damping characteristics in the design; and the effects of motion velocity.

  1. The science of and advanced technology for cost-effective manufacture of high precision engineering products. Volume 4. Thermal effects on the accuracy of numerically controlled machine tool

    NASA Astrophysics Data System (ADS)

    Venugopal, R.; Barash, M. M.; Liu, C. R.

    1985-10-01

    Thermal effects on the accuracy of numerically controlled machine tools are specially important in the context of unmanned manufacture or under conditions of precision metal cutting. Removal of the operator from the direct control of the metal cutting process has created problems in terms of maintaining accuracy. The objective of this research is to study thermal effects on the accuracy of numerically controlled machine tools. The initial part of the research report is concerned with the analysis of a hypothetical machine. The thermal characteristics of this machine are studied. Numerical methods for evaluating the errors exhibited by the slides of the machine are proposed and the possibility of predicting thermally induced errors by the use of regression equations is investigated. A method for computing the workspace error is also presented. The final part is concerned with the actual measurement of errors on a modern CNC machining center. Thermal influences on the errors is the main objective of the experimental work. Thermal influences on the errors of machine tools are predictable. Techniques for determining thermal effects on machine tools at a design stage are also presented. ; Error models and prediction; Metrology; Automation.

  2. Mining the Galaxy Zoo Database: Machine Learning Applications

    NASA Astrophysics Data System (ADS)

    Borne, Kirk D.; Wallin, J.; Vedachalam, A.; Baehr, S.; Lintott, C.; Darg, D.; Smith, A.; Fortson, L.

    2010-01-01

    The new Zooniverse initiative is addressing the data flood in the sciences through a transformative partnership between professional scientists, volunteer citizen scientists, and machines. As part of this project, we are exploring the application of machine learning techniques to data mining problems associated with the large and growing database of volunteer science results gathered by the Galaxy Zoo citizen science project. We will describe the basic challenge, some machine learning approaches, and early results. One of the motivators for this study is the acquisition (through the Galaxy Zoo results database) of approximately 100 million classification labels for roughly one million galaxies, yielding a tremendously large and rich set of training examples for improving automated galaxy morphological classification algorithms. In our first case study, the goal is to learn which morphological and photometric features in the Sloan Digital Sky Survey (SDSS) database correlate most strongly with user-selected galaxy morphological class. As a corollary to this study, we are also aiming to identify which galaxy parameters in the SDSS database correspond to galaxies that have been the most difficult to classify (based upon large dispersion in their volunter-provided classifications). Our second case study will focus on similar data mining analyses and machine leaning algorithms applied to the Galaxy Zoo catalog of merging and interacting galaxies. The outcomes of this project will have applications in future large sky surveys, such as the LSST (Large Synoptic Survey Telescope) project, which will generate a catalog of 20 billion galaxies and will produce an additional astronomical alert database of approximately 100 thousand events each night for 10 years -- the capabilities and algorithms that we are exploring will assist in the rapid characterization and classification of such massive data streams. This research has been supported in part through NSF award #0941610.

  3. Extreme learning machine for ranking: generalization analysis and applications.

    PubMed

    Chen, Hong; Peng, Jiangtao; Zhou, Yicong; Li, Luoqing; Pan, Zhibin

    2014-05-01

    The extreme learning machine (ELM) has attracted increasing attention recently with its successful applications in classification and regression. In this paper, we investigate the generalization performance of ELM-based ranking. A new regularized ranking algorithm is proposed based on the combinations of activation functions in ELM. The generalization analysis is established for the ELM-based ranking (ELMRank) in terms of the covering numbers of hypothesis space. Empirical results on the benchmark datasets show the competitive performance of the ELMRank over the state-of-the-art ranking methods. PMID:24590011

  4. LLNL's Precision Compton Scattering Light Source: Status & Applications

    NASA Astrophysics Data System (ADS)

    Hartemann, F. V.; Albert, F.; Anderson, S. G.; Bayramian, A. J.; Cross, R. R.; Ebbers, C. A.; Gibson, D. J.; Houck, T. L.; Marsh, R. A.; Messerly, M. J.; Shverdin, M. Y.; Wu, S. S.; Scarpetti, R. D.; Siders, C. W.; McNabb, D. P.; Bonanno, R. E.; Barty, C. P. J.; Adolphsen, C. E.; Chu, T. S.; Jongewaard, E. N.; Li, Z.; Tantawi, S. G.; Vlieks, A. E.; Wang, J. W.; Raubenheimer, T. O.

    2010-11-01

    A precision, tunable, monochromatic (< 0.4% rms spectral width) source driven by a compact, high-gradient X-band linac designed in collaboration with SLAC is under construction at LLNL. High-brightness (250 pC, 3.5 ps, 0.4 mm.mrad), relativistic electron bunches will interact with a Joule-class, 10 ps, diode-pumped laser pulse to generate tunable >=-rays in the 0.5-2.5 MeV photon energy range. This >=-ray source will be used to excite nuclear resonance fluorescence (NRF) in various isotopes, of interest for homeland security, stockpile science and surveillance, nuclear fuel assay, and waste imaging and assay. The source current status will be discussed, along with important applications, including NRF and in situ ps thermal measurements. This work performed under the auspices of the U.S. DoE by LLNL under Contract DE-AC52-07NA27344, and funded by the DHS DNDO.

  5. Security Aspects of Smart Cards vs. Embedded Security in Machine-to-Machine (M2M) Advanced Mobile Network Applications

    NASA Astrophysics Data System (ADS)

    Meyerstein, Mike; Cha, Inhyok; Shah, Yogendra

    The Third Generation Partnership Project (3GPP) standardisation group currently discusses advanced applications of mobile networks such as Machine-to-Machine (M2M) communication. Several security issues arise in these contexts which warrant a fresh look at mobile networks’ security foundations, resting on smart cards. This paper contributes a security/efficiency analysis to this discussion and highlights the role of trusted platform technology to approach these issues.

  6. Precision grinding process development for brittle materials

    SciTech Connect

    Blaedel, K L; Davis, P J; Piscotty, M A

    1999-04-01

    High performance, brittle materials are the materials of choice for many of today's engineering applications. This paper describes three separate precision grinding processes developed at Lawrence Liver-more National Laboratory to machine precision ceramic components. Included in the discussion of the precision processes is a variety of grinding wheel dressing, truing and profiling techniques.

  7. Successful fabrication of a convex platform PMMA cell-counting slide using a high-precision perpendicular dual-spindle CNC machine tool

    NASA Astrophysics Data System (ADS)

    Chen, Shun-Tong; Chang, Chih-Hsien

    2013-12-01

    This study presents a novel approach to the fabrication of a biomedical-mold for producing convex platform PMMA (poly-methyl-meth-acrylate) slides for counting cells. These slides allow for the microscopic examination of urine sediment cells. Manufacturing of such slides incorporates three important procedures: (1) the development of a tabletop high-precision dual-spindle CNC (computerized numerical control) machine tool; (2) the formation of a boron-doped polycrystalline composite diamond (BD-PCD) wheel-tool on the machine tool developed in procedure (1); and (3) the cutting of a multi-groove-biomedical-mold array using the formed diamond wheel-tool in situ on the developed machine. The machine incorporates a hybrid working platform providing wheel-tool thinning using spark erosion to cut, polish, and deburr microgrooves on NAK80 steel directly. With consideration given for the electrical conductive properties of BD-PCD, the diamond wheel-tool is thinned to a thickness of 5 µm by rotary wire electrical discharge machining. The thinned wheel-tool can grind microgrooves 10 µm wide. An embedded design, which inserts a close fitting precision core into the biomedical-mold to create step-difference (concave inward) of 50 µm in height between the core and the mold, is also proposed and realized. The perpendicular dual-spindles and precision rotary stage are features that allow for biomedical-mold machining without the necessity of uploading and repositioning materials until all tasks are completed. A PMMA biomedical-slide with a plurality of juxtaposed counting chambers is formed and its usefulness verified.

  8. [Application of precision medicine in obesity and metabolic disease surgery].

    PubMed

    Wang, Cunchuan; Gao, Zhiguang

    2016-01-01

    The U. S. A. president Obama called for a new initiative to fund precision medicine during his State of Union Address on January 20th, 2015, which meant that the human medicine enters a new era. The meaning of "precision medicine" is significantly similar to the concept of precision obesity and metabolic disease surgery, which was proposed by the author in early August 2011. Nowadays, obesity and metabolic disease surgery has been transformed from open surgery to laparoscopic surgery, the extensive mode to the precision mode. The key value concept is to minimize postoperative complication, minimize postoperative hospital stay and obtain the best effect of weight loss by accurate preoperative assessment, delicate operation, excellent postoperative management and scientific follow-up. The precision obesity and metabolic disease surgery has more development space in the future. PMID:26797833

  9. Waste reduction using carbon dioxide: A solvent substitute for precision cleaning applications

    SciTech Connect

    Phelphs, M.R.; Hogan, M.O.; Snowden-Swan, L.J.

    1995-05-01

    The U.S. Department of Energy`s (DOE) Industrial Waste Program (IWP) has been sponsoring the research, development, and commercialization of supercritical fluid cleaning technology for replacement of traditional solvent cleaning processes. Los Alamos National Laboratory and Pacific Northwest Laboratory have been working through this collaborative effort to test the efficacy of carbon dioxide (CO{sub 2}) cleaning. Tests were performed on a variety of substrates at various solvent conditions for a large number of common contaminants to characterize cleaning performance. Cleaning efficiencies with respect to system dynamics were also studied. Results of these tests show that supercritical and near-critical carbon dioxide is not only an effective solvent for precision cleaning applications of parts such as gyroscopes, bearing assemblies, and machine tools but is also feasible for bulk cleaning operations for a variety of industrial needs. It has been tested and shown to be effective for a range of substrates including laser optics components, computer disk drives, and cloth rags. Metals, including stainless steel, beryllium, gold, silver, copper and others; ceramics; and elastomeric seals such as Teflon, silicone, and epoxy potting compounds are highly compatible with SuperCritical CO{sub 2} (SCCO{sub 2}). Many contaminants, including silicones, Krytox, hydrocarbons, esters, fluorocarbons, gyroscope damping and fill fluids, and machining oils and lubricating oils, will dissolve in SCCO{sub 2}. In general, nonpolar, hydrophobic contaminants such as oils dissolve well, while hydrophilic contaminants such as inorganic salts do not. The parts and contaminants mentioned here are not the only applications for SCCO, cleaning, as the full range of possibilities is still being defined by developers and users of the technology. The many advantages of SCCO{sub 2} indicate that it is a technology that should carry industrial cleaning operations into the future.

  10. Picosecond and nanosecond pulse delivery through a hollow-core Negative Curvature Fiber for micro-machining applications.

    PubMed

    Jaworski, Piotr; Yu, Fei; Maier, Robert R J; Wadsworth, William J; Knight, Jonathan C; Shephard, Jonathan D; Hand, Duncan P

    2013-09-23

    We present high average power picosecond and nanosecond pulse delivery at 1030 nm and 1064 nm wavelengths respectively through a novel hollow-core Negative Curvature Fiber (NCF) for high-precision micro-machining applications. Picosecond pulses with an average power above 36 W and energies of 92 µJ, corresponding to a peak power density of 1.5 TWcm⁻² have been transmitted through the fiber without introducing any damage to the input and output fiber end-faces. High-energy nanosecond pulses (>1 mJ), which are ideal for micro-machining have been successfully delivered through the NCF with a coupling efficiency of 92%. Picosecond and nanosecond pulse delivery have been demonstrated in fiber-based laser micro-machining of fused silica, aluminum and titanium.

  11. Precise satellite orbit determination with particular application to ERS-1

    NASA Astrophysics Data System (ADS)

    Fernandes, Maria Joana Afonso Pereira

    The motivation behind this study is twofold. First to assess the accuracy of ERS-1 long arc ephemerides using state of the art models. Second, to develop improved methods for determining precise ERS-1 orbits using either short or long arc techniques. The SATAN programs, for the computation of satellite orbits using laser data were used. Several facilities were added to the original programs: the processing of PRARE range and altimeter data, and a number of algorithms that allow more flexible solutions by adjusting a number of additional parameters. The first part of this study, before the launch of ERS-1, was done with SEAS AT data. The accuracy of SEASAT orbits computed with PRARE simulated data has been determined. The effect of temporal distribution of tracking data along the arc and the extent to which altimetry can replace range data have been investigated. The second part starts with the computation of ERS-1 long arc solutions using laser data. Some aspects of modelling the two main forces affecting ERS-l's orbit are investigated. With regard to the gravitational forces, the adjustment of a set of geopotential coefficients has been considered. With respect to atmospheric drag, extensive research has been carried out on determining the influence on orbit accuracy of the measurements of solar fluxes (P10.7 indices) and geomagnetic activity (Kp indices) used by the atmospheric model in the computation of atmospheric density at satellite height. Two new short arc methods have been developed: the Constrained and the Bayesian method. Both methods are dynamic and consist of solving for the 6 osculating elements. Using different techniques, both methods overcome the problem of normal matrix ill- conditioning by constraining the solution. The accuracy and applicability of these methods are discussed and compared with the traditional non-dynamic TAR method.

  12. Development of portable laser machining system for laser writing applications

    NASA Astrophysics Data System (ADS)

    Hsiao, Wen-Tse; Tseng, Shih-Feng; Chung, Chien-Kai; Chen, Pin-Hung; Chen, Ming-Fei

    2013-03-01

    This study presents a portable laser machining system that consists of a fiber-optic diode laser source with a wavelength of 808 nm, optic/opto-mechanical components, a laser scanning module, and a laser energy control module. The laser beam quality was measured at different operation frequencies during system evaluation. The experimental results of beam profile evaluation indicate that the enlarged collimated beam was the TEM00 mode with a roundness of approximately of 96%. The output laser power level increased as the pulse frequency increased during laser power evaluation. To control the rotating angle of the galvanometric scanning system, the deflective angle was adjusted using a 0.192 voltage to obtain a deflective value of 1mm and the maximum scan field of 100 × 100mm2. The laser source operated at different frequencies, with pulse widths ranging from 530 to 48 μs. Finally, the proposed machine can also be used for black thick paper laser writing applications.

  13. Guest Editorial Electric Machines in Renewable Energy Applications

    SciTech Connect

    Aliprantis, Dionysios; El-Sharkawi, Mohamed; Muljadi, Eduard; Brown, Ian; Chiba, Akira; Dorrell, David; Erlich, Istvan; Kerszenbaum, Isidor Izzy; Levi, Emil; Mayor, Kevin; Mohammed, Osama; Papathanassiou, Stavros; Popescu, Mircea; Qiao, Wei; Wu, Dezheng

    2015-12-01

    The main objective of this special issue is to collect and disseminate publications that highlight recent advances and breakthroughs in the area of renewable energy resources. The use of these resources for production of electricity is increasing rapidly worldwide. As of 2015, a majority of countries have set renewable electricity targets in the 10%-40% range to be achieved by 2020-2030, with a few notable exceptions aiming for 100% generation by renewables. We are experiencing a truly unprecedented transition away from fossil fuels, driven by environmental, energy security, and socio-economic factors.Electric machines can be found in a wide range of renewable energy applications, such as wind turbines, hydropower and hydrokinetic systems, flywheel energy storage devices, and low-power energy harvesting systems. Hence, the design of reliable, efficient, cost-effective, and controllable electric machines is crucial in enabling even higher penetrations of renewable energy systems in the smart grid of the future. In addition, power electronic converter design and control is critical, as they provide essential controllability, flexibility, grid interface, and integration functions.

  14. Investigating inhomogeneous Szekeres models and their applications to precision cosmology

    NASA Astrophysics Data System (ADS)

    Peel, Austin Chandler

    Exact solutions of Einstein's field equations that can describe the evolution of complex structures in the universe provide complementary frameworks to standard perturbation theory in which to analyze cosmological and astrophysical phenomena. The flexibility and generality of the inhomogeneous and anisotropic Szekeres metric make it the best known exact solution to explore nonlinearities in the universe. We study applications of Szekeres models to precision cosmology, focusing on the influence of inhomogeneities in two primary contexts---the growth rate of cosmic structures and biases in distance determinations to remote sources. We first define and derive evolution equations for a Szekeres density contrast, which quantifies exact deviations from a smooth background cosmology. Solving these equations and comparing to the usual perturbative approach, we find that for models with the same matter content, the Szekeres growth rate is larger through the matter-dominated cosmic era. Including a cosmological constant, we consider exact global perturbations, as well as the evolution of a single extended structure surrounded by an almost homogeneous background. For the former, we use growth data to obtain a best fit Szekeres model and find that it can fit the data as well as the standard Lambda-Cold Dark Matter (LCDM) cosmological model but with different cosmological parameters. Next, to study effects of inhomogeneities on distance measures, we build an exact relativistic Swiss-cheese model of the universe, where a large number of non-symmetric and randomly placed Szekeres structures are embedded within a LCDM background. Solving the full relativistic propagation equations, light beams are traced through the model, where they traverse the inhomogeneous structures in a way that mimics the paths of real light beams in the universe. For beams crossing a single structure, their magnification or demagnification reflects primarily the net density encountered along the path

  15. Open Quantum Systems with Applications to Precision Measurements

    NASA Astrophysics Data System (ADS)

    Tieri, David

    A spectrally pure coherent light source is an important component in precision measurement applications, such as an atomic clock. The more spectrally pure the coherent light source, or the narrower the linewidth of its power spectrum, the better for atomic clock experiments. A coherent light light source, such as a laser, is intrinsically an open quantum system, meaning that it gains and loses energy from an external environment. The aim of this thesis is to study various open quantum systems in an attempt to discover a scheme in which an extremely spectrally pure coherent light source might be realized. Therefore, this thesis begins by introducing the two main approaches to treating open quantum systems, the quantum master equation approach, and the quantum Langevin equation approach. In addition to deriving these from first principles, many of the solution methods to these approaches are given and then demonstrated using computer simulations. These include the quantum jump algorithm, the quantum state diffusion algorithm, the cumulant expansion method, and the method of c-number Langevin equations. Using these methods, the theory of the crossover between lasing and steady state superradiance is presented. It is shown that lasing and steady state superradiance might be demonstrated in the same physical system, but in different parameter regimes. The parameter space between these two extreme limits is explored, and the benefits and drawbacks of operating a system at a given set of parameters, i.e. to achieve the most spectrally pure light source, are discussed. We also consider the phase stability of a laser that is locked to a cavity QED system comprised of atoms with an ultra-narrow optical transition. Although the atomic motion introduces Doppler broadening, the standing wave nature of the cavity causes saturated absorption, which can be used to achieve an extremely high degree of phase stabilization. The inhomogeneity introduced by finite atomic velocities can

  16. [Emphasis on the application of precision medicine in ophthalmology].

    PubMed

    Sun, X D; Zhu, H

    2016-02-01

    Accompany with dramatically growth of large-scale biological databases (such as human genome sequence), improvement of life science and development of international clinical trials, science offers great potential for improving health care through precision medicine. As a hot topic recently, precision medicine might launch a revolution of the methodology in medical research. How to achieve precision medicine in clinical ophthalmology by means of biological data mining is a challenge for ophthalmologist-scientists. The best approach for advanced individual medicine is to buildup the digital ophthalmology, which includes human eye biobank, national biological databases network, clinical department, basic research lab, and international clinical trial center. The system of digital ophthalmology could explore the methods for ophthalmology research, integrate the source of eye biologic databases, promote international cooperation, and thus eventually supply the opportunity for translational medicine.

  17. [Emphasis on the application of precision medicine in ophthalmology].

    PubMed

    Sun, X D; Zhu, H

    2016-02-01

    Accompany with dramatically growth of large-scale biological databases (such as human genome sequence), improvement of life science and development of international clinical trials, science offers great potential for improving health care through precision medicine. As a hot topic recently, precision medicine might launch a revolution of the methodology in medical research. How to achieve precision medicine in clinical ophthalmology by means of biological data mining is a challenge for ophthalmologist-scientists. The best approach for advanced individual medicine is to buildup the digital ophthalmology, which includes human eye biobank, national biological databases network, clinical department, basic research lab, and international clinical trial center. The system of digital ophthalmology could explore the methods for ophthalmology research, integrate the source of eye biologic databases, promote international cooperation, and thus eventually supply the opportunity for translational medicine. PMID:26906701

  18. Applications of laser precisely processing technology in solar cells

    NASA Astrophysics Data System (ADS)

    Wang, Hong-Jie; Cheng, Hua; Xie, Kang-Wen; Lu, Fu-Yun; Du, Yong-Chao

    2007-09-01

    According to the design method of laser resonator cavity, we optimized the primary parameters of resonator and utilized LD arrays symmetrically pumping manner to implementing output of the high-brightness laser in our laser cutter, then which was applied to precisely cutting the conductive film of CuInSe2 solar cells, the buried contact silicon solar cells’ electrode groove, and perforating in wafer which is used to the emitter wrap through silicon solar cells. Laser processing precision was less than 40 μ m, the results have met solar cell’s fabrication technology, and made finally the buried cells’ conversion efficiency be improved from 18% to 21%.

  19. Monitoring frog communities: An application of machine learning

    SciTech Connect

    Taylor, A.; Watson, G.; Grigg, G.; McCallum, H.

    1996-12-31

    Automatic recognition of animal vocalizations would be a valuable tool for a variety of biological research and environmental monitoring applications. We report the development of a software system which can recognize the vocalizations of 22 species of frogs which occur in an area of northern Australia. This software system will be used in unattended operation to monitor the effect on frog populations of the introduced Cane Toad. The system is based around classification of local peaks in the spectrogram of the audio signal using Quinlan`s machine learning system, C4.5. Unreliable identifications of peaks are aggregated together using a hierarchical structure of segments based on the typical temporal vocalization species` patterns. This produces robust system performance.

  20. Clinical applications of the continuous flow blood separator machine.

    PubMed Central

    Oon, C J; Hobbs, J R

    1975-01-01

    The NCl/IBM or Aminco Continuous Flow Blood Separator Machine is a safe apparatus for the selective removal or exchange of either packed red blood cells, leucocyte-rich or platelet-rich layers or plasma. Abnormal fractions from any of these layers may be collected and discarded. Normal constituents may be collected for therapeutic uses. The wide scope of its applications includes important uses in clinical immunology: temporary provision of good leucocytes or platelets; harvesting of immune leucocytes (preparation of transfer factor at up to 10 units per harvest); removal of cryo- or macro-globulins, immune complexes or blocking factors; replacement therapy for antibody or complement deficiencies. Examples are given of such uses together with some of the medical problems so far encountered. Images FIG. 6 PMID:1106917

  1. Machine learning applications in cancer prognosis and prediction.

    PubMed

    Kourou, Konstantina; Exarchos, Themis P; Exarchos, Konstantinos P; Karamouzis, Michalis V; Fotiadis, Dimitrios I

    2015-01-01

    Cancer has been characterized as a heterogeneous disease consisting of many different subtypes. The early diagnosis and prognosis of a cancer type have become a necessity in cancer research, as it can facilitate the subsequent clinical management of patients. The importance of classifying cancer patients into high or low risk groups has led many research teams, from the biomedical and the bioinformatics field, to study the application of machine learning (ML) methods. Therefore, these techniques have been utilized as an aim to model the progression and treatment of cancerous conditions. In addition, the ability of ML tools to detect key features from complex datasets reveals their importance. A variety of these techniques, including Artificial Neural Networks (ANNs), Bayesian Networks (BNs), Support Vector Machines (SVMs) and Decision Trees (DTs) have been widely applied in cancer research for the development of predictive models, resulting in effective and accurate decision making. Even though it is evident that the use of ML methods can improve our understanding of cancer progression, an appropriate level of validation is needed in order for these methods to be considered in the everyday clinical practice. In this work, we present a review of recent ML approaches employed in the modeling of cancer progression. The predictive models discussed here are based on various supervised ML techniques as well as on different input features and data samples. Given the growing trend on the application of ML methods in cancer research, we present here the most recent publications that employ these techniques as an aim to model cancer risk or patient outcomes.

  2. Machine learning applications in cancer prognosis and prediction

    PubMed Central

    Kourou, Konstantina; Exarchos, Themis P.; Exarchos, Konstantinos P.; Karamouzis, Michalis V.; Fotiadis, Dimitrios I.

    2014-01-01

    Cancer has been characterized as a heterogeneous disease consisting of many different subtypes. The early diagnosis and prognosis of a cancer type have become a necessity in cancer research, as it can facilitate the subsequent clinical management of patients. The importance of classifying cancer patients into high or low risk groups has led many research teams, from the biomedical and the bioinformatics field, to study the application of machine learning (ML) methods. Therefore, these techniques have been utilized as an aim to model the progression and treatment of cancerous conditions. In addition, the ability of ML tools to detect key features from complex datasets reveals their importance. A variety of these techniques, including Artificial Neural Networks (ANNs), Bayesian Networks (BNs), Support Vector Machines (SVMs) and Decision Trees (DTs) have been widely applied in cancer research for the development of predictive models, resulting in effective and accurate decision making. Even though it is evident that the use of ML methods can improve our understanding of cancer progression, an appropriate level of validation is needed in order for these methods to be considered in the everyday clinical practice. In this work, we present a review of recent ML approaches employed in the modeling of cancer progression. The predictive models discussed here are based on various supervised ML techniques as well as on different input features and data samples. Given the growing trend on the application of ML methods in cancer research, we present here the most recent publications that employ these techniques as an aim to model cancer risk or patient outcomes. PMID:25750696

  3. Proceedings of the Eleventh Annual Precise Time and Time Interval (PTTI) Application and Planning Meeting. [conference

    NASA Technical Reports Server (NTRS)

    Wardrip, S. C. (Editor)

    1979-01-01

    Thirty eight papers are presented addressing various aspects of precise time and time interval applications. Areas discussed include: past accomplishments; state of the art systems; new and useful applications, procedures, and techniques; and fruitful directions for research efforts.

  4. Application of extreme learning machine for estimation of wind speed distribution

    NASA Astrophysics Data System (ADS)

    Shamshirband, Shahaboddin; Mohammadi, Kasra; Tong, Chong Wen; Petković, Dalibor; Porcu, Emilio; Mostafaeipour, Ali; Ch, Sudheer; Sedaghat, Ahmad

    2016-03-01

    The knowledge of the probabilistic wind speed distribution is of particular significance in reliable evaluation of the wind energy potential and effective adoption of site specific wind turbines. Among all proposed probability density functions, the two-parameter Weibull function has been extensively endorsed and utilized to model wind speeds and express wind speed distribution in various locations. In this research work, extreme learning machine (ELM) is employed to compute the shape ( k) and scale ( c) factors of Weibull distribution function. The developed ELM model is trained and tested based upon two widely successful methods used to estimate k and c parameters. The efficiency and accuracy of ELM is compared against support vector machine, artificial neural network and genetic programming for estimating the same Weibull parameters. The survey results reveal that applying ELM approach is eventuated in attaining further precision for estimation of both Weibull parameters compared to other methods evaluated. Mean absolute percentage error, mean absolute bias error and root mean square error for k are 8.4600 %, 0.1783 and 0.2371, while for c are 0.2143 %, 0.0118 and 0.0192 m/s, respectively. In conclusion, it is conclusively found that application of ELM is particularly promising as an alternative method to estimate Weibull k and c factors.

  5. [Application to dental casting machine of the rapid heating infrared image furnace (author's transl)].

    PubMed

    Etchu, Y; Noguchi, H

    1980-10-01

    The authors tried to manufacture a casting machine in dentistry by application of the infrared image furnace with a high heating speed and an easy control of a heating temperature. This machine melts an alloy in a carbon crucible set in the furnace, held in the horizontal position. Then, the furnace is turned to the vertical position to drop a melted alloy on the casting mold, and the alloy is cast in the mold by the pressure of Argon gas. The functions of trial casting machine were follows. 1. The trial casting machine was capable of heating to 1250 degrees C within one minute under 4 kW electric power. 2. The castability of the 20% Au-Pd-Ag commercial alloy cast in all casting conditions by the trial casting machine was higher than that of Thermotrol D-2 automatic centrifugal casting machine. 3. Castings of the trial casting machine showed higher tensile strength and elongation than those of the centrifugal casting machine, and the deviation of values got by the trial casting machine was small. In particular, some casting of the trial casting machine showed three times or over elongation values as compared with those of the centrifugal casting machine. 4. When casting conditions (casting temperature, casting pressure) of the trial casting machine changed, the physical properties of castings did not change so much. However, when the mold was not prevented from heating by the furnace in casting, the elongation of castings increased.

  6. Long-range nanopositioning and nanomeasuring machine for application to micro- and nanotechnology

    NASA Astrophysics Data System (ADS)

    Jäger, Gerd; Hausotte, Tino; Büchner, Hans-Joachim; Manske, Eberhard; Schmidt, Ingomar; Mastylo, Rostyslav

    2006-03-01

    The paper describes the operation of a high-precision long range three-dimensional nanopositioning and nanomeasuring machine (NPM-Machine). The NPM-Machine has been developed by the Institute of Process Measurement and Sensor Technology of the Technische Universität Ilmenau. The machine was successfully tested and continually improved in the last few years. The machines are operating successfully in several German and foreign research institutes including the Physikalisch-Technische Bundesanstalt (PTB). Three plane mirror miniature interferometers are installed into the NPM-machine having a resolution of less than 0,1 nm over the entire positioning and measuring range of 25 mm x 25 mm x 5 mm. An Abbe offset-free design of the three miniature plane mirror interferometers and applying a new concept for compensating systematic errors resulting from mechanical guide systems provide extraordinary accuracy with an expanded uncertainty of only 5 - 10 nm. The integration of several, optical and tactile probe systems and nanotools makes the NPM-Machine suitable for various tasks, such as large-area scanning probe microscopy, mask and wafer inspection, nanostructuring, biotechnology and genetic engineering as well as measuring mechanical precision workpieces, precision treatment and for engineering new material. Various developed probe systems have been integrated into the NPM-Machine. The measurement results of a focus sensor, metrological AFM, white light sensor, tactile stylus probe and of a 3D-micro-touch-probe are presented. Single beam-, double beam- and triple beam interferometers built in the NPM-Machine for six degrees of freedom measurements are described.

  7. A precision, thermally-activated driver for space application

    NASA Technical Reports Server (NTRS)

    Murray, Robert C.; Walsh, Robert F.; Kinard, William H.

    1986-01-01

    A space qualified, precision, large force, thermally-activated driver that has been developed jointly by the NASA Langley Research Center and PRC Kentron is described. The driver consists of a sealed hydraulic cylinder containing a metal bellows, a bellows plug, a coil spring, a spring retainer, and output shaft, a shaft guide, and a quantity of silicone oil. Temperature changes cause the silicone oil to expand or contract thus contracting or expanding the bellows/spring assembly thereby extending or retracting the output shaft.

  8. A floating-point/multiple-precision processor for airborne applications

    NASA Technical Reports Server (NTRS)

    Yee, R.

    1982-01-01

    A compact input output (I/O) numerical processor capable of performing floating-point, multiple precision and other arithmetic functions at execution times which are at least 100 times faster than comparable software emulation is described. The I/O device is a microcomputer system containing a 16 bit microprocessor, a numerical coprocessor with eight 80 bit registers running at a 5 MHz clock rate, 18K random access memory (RAM) and 16K electrically programmable read only memory (EPROM). The processor acts as an intelligent slave to the host computer and can be programmed in high order languages such as FORTRAN and PL/M-86.

  9. Precision machining, polishing and measurement of mechanical and toxicological properties of lead tungstate crystals for the CMS electromagnetic calorimeter

    SciTech Connect

    Wuest, C.R.; Fuchs, B.A.; Shi, X.

    1995-08-01

    We have developed new machining and polishing techniques that have previously been applied to large scintillating crystal arrays for high energy physics experiments such as the Barium Fluoride Electromagnetic Calorimeter for the GEM Detector at SSCL, the LCsI Electromagnetic Calorimeter for the BaBar Detector at PEP-II B Factory at SLAC and the 110,000 crystal CMS Lead Tungstate Electromagnetic Calorimeter at LHC at CERN. We discuss earlier results achieved with diamond machining and polishing methods and present new results on diamond machining of lead tungstate crystals. Additionally we present new results on mechanical properties of lead tungstate including toxicological data important for the safe handling and processing of this material.

  10. Application of case-based reasoning for machining parameters selection

    NASA Astrophysics Data System (ADS)

    Grabowik, C.; Kalinowski, K.; Krenczyk, D.; Paprocka, I.; Kempa, W.

    2016-08-01

    Process planning, as one of the most important stage of the technological production preparation, consists in selection of manufacturing operations taking into account the minimal manufacturing cost. The minimal manufacturing cost could be achieved by selection of the best sequence of manufacturing operations, machine tools, manufacturing tools, and accompanying machining parameters selection. On the other hand, it is almost impossible, especially in industrial conditions, to design an optimal process plan, first of all due to restrictions imposed by the installed in the factory machine park. Taking into consideration above, machining parameter selection seems to be one of the potential areas of optimization. In manual process planning process engineers select machining parameters using selection rules and data stored in manuals and tool catalogues. It makes this process time and labour consuming and non-error free. On the other hand, in workshop practice, machine operators select parameters having their skills and habits in mind. It could be a reason for suboptimal process planning. Considering this, new methods of machining parameters selection free of human factor influence are still sought. In our approach, we propose to apply case-based reasoning for machining parameter selection. In the paper, a detailed description of our approach is presented.

  11. Proceedings of the 7th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The Proceedings contain the papers presented at the Seventh Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting and the edited record of the discussion period following each paper. This meeting provided a forum to promote more effective, efficient, economical and skillful applications of PTTI technology to the many problem areas to which PTTI offers solutions. Specifically the purpose of the meeting is to: disseminate, coordinate, and exchange practical information associated with precise time and frequency; acquaint systems engineers, technicians and managers with precise time and frequency technology and its applications; and review present and future requirements for PTTI.

  12. Precision injection molding of freeform optics

    NASA Astrophysics Data System (ADS)

    Fang, Fengzhou; Zhang, Nan; Zhang, Xiaodong

    2016-08-01

    Precision injection molding is the most efficient mass production technology for manufacturing plastic optics. Applications of plastic optics in field of imaging, illumination, and concentration demonstrate a variety of complex surface forms, developing from conventional plano and spherical surfaces to aspheric and freeform surfaces. It requires high optical quality with high form accuracy and lower residual stresses, which challenges both optical tool inserts machining and precision injection molding process. The present paper reviews recent progress in mold tool machining and precision injection molding, with more emphasis on precision injection molding. The challenges and future development trend are also discussed.

  13. Proceedings of the 8th Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The Proceedings contain the papers presented at the Eight Annual Precise Time and Tme Interval PTTI Applications and Planning Meeting. The edited record of the discussions following the papers and the panel discussions are also included. This meeting provided a forum for the exchange of information on precise time and frequency technology among members of the scientific community and persons with program applications. The 282 registered attendees came from various U.S. Government agencies, private industry, universities and a number of foreign countries were represented. In this meeting, papers were presented that emphasized: (1) definitions and international regulations of precise time sources and users, (2) the scientific foundations of Hydrogen Maser standards, the current developments in this field and the application experience, and (3) how to measure the stability performance properties of precise standards. As in the previous meetings, update and new papers were presented on system applications with past, present and future requirements identified.

  14. Application of x-ray techniques in precision farming

    NASA Astrophysics Data System (ADS)

    Arslan, Selcuk; Inanc, Feyzi; Gray, Joseph N.; Colvin, Thomas S.

    2000-05-01

    The precision farming is a relatively new concept basing farming upon quantitative determination of various parameters in the farming practices. One of these parameters is accurate measurement of grain flow rates on real time basis. Although there are various techniques already available for this purpose, x-rays provide a very competitive alternative to the current state of art. In this work, the use of low energy bremsstrahlung x-ray, up to 30 keV, densitometry is demonstrated for grain flow rate measurements. Mass flow rates for corn are related to measured x-ray intensity in gray scale units with a 0.99 correlation coefficient for flow rates ranging from 2 kg/s to 6 kg/s. Higher flow rate values can be measured by using slightly more energetic x-rays or a higher tube current. Measurements were done in real time at a 30 Hz sampling rate. Flow rate measurements are independent of grain moisture due to a negligible change in the x-ray attenuation coefficients at typical moisture content values from 15% to 25%. Grain flow profile changes do not affect measurement accuracy. X-rays easily capture variations in the corn stream. Due to the low energy of the x-ray photons, biological shielding can easily be accomplished with 2 mm thick lead foil or 5 mm of steel.

  15. A fuzzy clustering application to precise orbit determination

    NASA Astrophysics Data System (ADS)

    Soto, Jesus; Vigo Aguiar, M. Isabel; Flores-Sintas, Antonio

    2007-07-01

    In recent years, fuzzy logic techniques have been successfully applied in geodesy problems, in particular to GPS. The aim of this work is to test a fuzzy-logic method with an enhanced probability function as a tool to provide a reliable criteria for weighting scheme for satellite-laser-ranging (SLR) station observations, seeking to optimize their contribution to the precise orbit determination (POD) problem. The data regarding the stations were provided by the International Laser Ranging Service (ILRS), NASA/Crustal Dynamics Data Information System (CDDIS) provided the satellite data for testing the method. The software for processing the data is GEODYN II provided by NASA/Goddard Space Flight Center (GSFC). Factors to be considered in the fuzzy-logic clustering are: the total number of LAGEOS passes during the past 12 months, the stability measure of short- and long-term biases, the percentage of LAGEOS normal points that were accepted in CSR weekly LAGEOS analysis, and the RMS uncertainty of the station coordinates. A fuzzy-logic statistical method allows classifying the stations through a clear `degree of belonging' to each station group. This degree of belonging translates into a suitable weight to be assigned to each station in the global solutionE The first tests carried out showed improvements in the RMS of the global POD solution as well as individual stations, to within a few millimeters. We expect further work would lead to further improvements.

  16. Current status and future directions of precision agriculture for aerial application in the USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Precision aerial application in the USA is less than a decade old since the development of the first variable-rate aerial application system. Many areas of the United States rely on readily available agricultural airplanes or helicopters for pest management. Variable-rate aerial application provides...

  17. A facility for precise temperature control applications in microgravity

    NASA Astrophysics Data System (ADS)

    Glicksman, M. E.; Lograsso, T. A.; Tirmizi, S. H.; Hahn, R. C.; Winsa, E.

    The general design, main components, and operation of the isothermal dendritic growth apparatus (IDGA) designed for microgravity experimentation are described. The four major subsystems of the IDGA are a temperature controlled thermostatic bath capable of milli-kelvin stability, a photographic data collection system, a crystal growth chamber, and a growth detection system to initiate data collection. Some of the specific experiments that could utilize the capabilities of the IDGA are dendritic growth in alloys, monotectic systems, life science experiments, and technological applications.

  18. 3D sensing for machine guidance in meat cutting applications

    NASA Astrophysics Data System (ADS)

    Daley, Wayne; Britton, Doug; Usher, Colin; Diao, Mamadou; Ruffin, Kevin

    2005-11-01

    Most cutting and deboning operations in meat processing require accurate cuts be made to obtain maximum yield and ensure food safety. This is a significant concern for purveyors of deboned product. This task is made more difficult by the variability that is present in most natural products. The specific application of interest in this paper is the production of deboned poultry breast. This is typically obtained from a cut of the broiler called a 'front half' that includes the breast and the wings. The deboning operation typically consists of a cut that starts at the shoulder joint and then continues along the scapula. Attentive humans with training do a very good job of making this cut. The breast meat is then removed by pulling on the wings. Inaccurate cuts lead to poor yield (amount of boneless meat obtained relative to the weight of the whole carcass) and increase the probability that bone fragments might end up in the product. As equipment designers seek to automate the deboning operation, the cutting task has been a significant obstacle to developing automation that maximizes yield without generating unacceptable levels of bone fragments. The current solution is to sort the bone-in product into different weight ranges and then to adjust the deboning machines to the average of these weight ranges. We propose an approach for obtaining key cut points by extrapolation from external reference points based on the anatomy of the bird. We show that this approach can be implemented using a stereo imaging system, and the accuracy in locating the cut points of interest is significantly improved. This should result in more accurate cuts and with this concomitantly improved yield while reducing the incidence of bones. We also believe the approach could be extended to the processing of other species.

  19. Multimode vibration reduction concept for machine tools and automotive applications

    NASA Astrophysics Data System (ADS)

    Neugebauer, Reimund; Drossel, Welf-Guntram; Kranz, Burkhard; Kunze, Holger

    2005-05-01

    This paper reports a numerical and experimental study on a new multi mode vibration reduction concept for struts of machine tools or shafts of automotives. The example described in detail validates this new concept for high dynamic parallel kinematic struts. The structural advantages of parallel kinematic mechanisms are undisputed. However statical and dynamical bending and torsional loads must be considered during the design process of the structure and thus effect the shape of the strut geometry. The here described new actuator concept for multi mode vibration reduction is to influence these bending and torsional loads. It uses piezopatches based on the MFC technology licensed by NASA. Initial simulation and experimental tests were done at an one side clamped aluminium beam with applicated 45°-MFC's on both sides. Simulation results show, that driving the piezos in opposite direction leads to a bending deflection of the beam, driving them in the same phase leads to a torsional deflection of the aluminium beam. Experimental measurements confirm the simulation results. The benefit we get is a decreased number of actuators for multimode vibration reduction. Likewise these actuators allow the separation or selective combination of bending and torsion. This new actuation concept is not limited on beams. Further simulations for cylindrical struts result in a design of a MFC-ring with eight segments with changing fiber orientation for separation of bending and torsion on struts and shafts. The selective controlled activation of each of the segments leads to bending in x-direction, bending in y-direction or torsion.

  20. A macro-micro robot for precise force applications

    NASA Technical Reports Server (NTRS)

    Marzwell, Neville I.; Wang, Yulun

    1993-01-01

    This paper describes an 8 degree-of-freedom macro-micro robot capable of performing tasks which require accurate force control. Applications such as polishing, finishing, grinding, deburring, and cleaning are a few examples of tasks which need this capability. Currently these tasks are either performed manually or with dedicated machinery because of the lack of a flexible and cost effective tool, such as a programmable force-controlled robot. The basic design and control of the macro-micro robot is described in this paper. A modular high-performance multiprocessor control system was designed to provide sufficient compute power for executing advanced control methods. An 8 degree of freedom macro-micro mechanism was constructed to enable accurate tip forces. Control algorithms based on the impedance control method were derived, coded, and load balanced for maximum execution speed on the multiprocessor system.

  1. A forestry application simulation of man-machine techniques for analyzing remotely sensed data

    NASA Technical Reports Server (NTRS)

    Berkebile, J.; Russell, J.; Lube, B.

    1976-01-01

    The typical steps in the analysis of remotely sensed data for a forestry applications example are simulated. The example uses numerically-oriented pattern recognition techniques and emphasizes man-machine interaction.

  2. Component based modelling of piezoelectric ultrasonic actuators for machining applications

    NASA Astrophysics Data System (ADS)

    Saleem, A.; Salah, M.; Ahmed, N.; Silberschmidt, V. V.

    2013-07-01

    Ultrasonically Assisted Machining (UAM) is an emerging technology that has been utilized to improve the surface finishing in machining processes such as turning, milling, and drilling. In this context, piezoelectric ultrasonic transducers are being used to vibrate the cutting tip while machining at predetermined amplitude and frequency. However, modelling and simulation of these transducers is a tedious and difficult task. This is due to the inherent nonlinearities associated with smart materials. Therefore, this paper presents a component-based model of ultrasonic transducers that mimics the nonlinear behaviour of such a system. The system is decomposed into components, a mathematical model of each component is created, and the whole system model is accomplished by aggregating the basic components' model. System parameters are identified using Finite Element technique which then has been used to simulate the system in Matlab/SIMULINK. Various operation conditions are tested and performed to demonstrate the system performance.

  3. Of Genes and Machines: Application of a Combination of Machine Learning Tools to Astronomy Data Sets

    NASA Astrophysics Data System (ADS)

    Heinis, S.; Kumar, S.; Gezari, S.; Burgett, W. S.; Chambers, K. C.; Draper, P. W.; Flewelling, H.; Kaiser, N.; Magnier, E. A.; Metcalfe, N.; Waters, C.

    2016-04-01

    We apply a combination of genetic algorithm (GA) and support vector machine (SVM) machine learning algorithms to solve two important problems faced by the astronomical community: star–galaxy separation and photometric redshift estimation of galaxies in survey catalogs. We use the GA to select the relevant features in the first step, followed by optimization of SVM parameters in the second step to obtain an optimal set of parameters to classify or regress, in the process of which we avoid overfitting. We apply our method to star–galaxy separation in Pan-STARRS1 data. We show that our method correctly classifies 98% of objects down to {i}{{P1}}=24.5, with a completeness (or true positive rate) of 99% for galaxies and 88% for stars. By combining colors with morphology, our star–galaxy separation method yields better results than the new SExtractor classifier spread_model, in particular at the faint end ({i}{{P1}}\\gt 22). We also use our method to derive photometric redshifts for galaxies in the COSMOS bright multiwavelength data set down to an error in (1+z) of σ =0.013, which compares well with estimates from spectral energy distribution fitting on the same data (σ =0.007) while making a significantly smaller number of assumptions.

  4. Of Genes and Machines: Application of a Combination of Machine Learning Tools to Astronomy Data Sets

    NASA Astrophysics Data System (ADS)

    Heinis, S.; Kumar, S.; Gezari, S.; Burgett, W. S.; Chambers, K. C.; Draper, P. W.; Flewelling, H.; Kaiser, N.; Magnier, E. A.; Metcalfe, N.; Waters, C.

    2016-04-01

    We apply a combination of genetic algorithm (GA) and support vector machine (SVM) machine learning algorithms to solve two important problems faced by the astronomical community: star-galaxy separation and photometric redshift estimation of galaxies in survey catalogs. We use the GA to select the relevant features in the first step, followed by optimization of SVM parameters in the second step to obtain an optimal set of parameters to classify or regress, in the process of which we avoid overfitting. We apply our method to star-galaxy separation in Pan-STARRS1 data. We show that our method correctly classifies 98% of objects down to {i}{{P1}}=24.5, with a completeness (or true positive rate) of 99% for galaxies and 88% for stars. By combining colors with morphology, our star-galaxy separation method yields better results than the new SExtractor classifier spread_model, in particular at the faint end ({i}{{P1}}\\gt 22). We also use our method to derive photometric redshifts for galaxies in the COSMOS bright multiwavelength data set down to an error in (1+z) of σ =0.013, which compares well with estimates from spectral energy distribution fitting on the same data (σ =0.007) while making a significantly smaller number of assumptions.

  5. A novel triple-actuating mechanism of an active air mount for vibration control of precision manufacturing machines: experimental work

    NASA Astrophysics Data System (ADS)

    Kim, Hyung-Tae; Kim, Cheol-Ho; Choi, Seung-Bok; Moon, Seok-Jun; Song, Won-Gil

    2014-07-01

    With the goal of vibration control and isolation in a clean room, we propose a new type of air mount which consists of pneumatic, electromagnetic (EM), and magnetorheological (MR) actuators. The air mount is installed below a semiconductor manufacturing machine to reduce the adverse effects caused by unwanted vibration. The proposed mechanism integrates the forces in a parallel connection of the three actuators. The MR part is designed to operate in an air spring in which the EM part is installed. The control logic is developed with a classical method and a switching mode to avoid operational mismatch among the forces developed. Based on extended microprocessors, a portable, embedded controller is installed to execute both nonlinear logic and digital communication with the peripherals. The pneumatic forces constantly support the heavy weight of an upper structure and maintain the level of the air mount. The MR damper handles the transient response, while the EM controller reduces the resonance response, which is switched mutually with a threshold. Vibration is detected by laser displacement sensors which have submicron resolution. The impact test results of three tons load weight demonstrate practical feasibility by showing that the proposed triple-actuating mechanism can reduce the transient response as well as the resonance in the air mount, resulting in accurate motion of the semiconductor manufacturing machine.

  6. Application of machine learning using support vector machines for crater detection from Martian digital topography data

    NASA Astrophysics Data System (ADS)

    Salamunićcar, Goran; Lončarić, Sven

    In our previous work, in order to extend the GT-57633 catalogue [PSS, 56 (15), 1992-2008] with still uncatalogued impact-craters, the following has been done [GRS, 48 (5), in press, doi:10.1109/TGRS.2009.2037750]: (1) the crater detection algorithm (CDA) based on digital elevation model (DEM) was developed; (2) using 1/128° MOLA data, this CDA proposed 414631 crater-candidates; (3) each crater-candidate was analyzed manually; and (4) 57592 were confirmed as correct detections. The resulting GT-115225 catalog is the significant result of this effort. However, to check such a large number of crater-candidates manually was a demanding task. This was the main motivation for work on improvement of the CDA in order to provide better classification of craters as true and false detections. To achieve this, we extended the CDA with the machine learning capability, using support vector machines (SVM). In the first step, the CDA (re)calculates numerous terrain morphometric attributes from DEM. For this purpose, already existing modules of the CDA from our previous work were reused in order to be capable to prepare these attributes. In addition, new attributes were introduced such as ellipse eccentricity and tilt. For machine learning purpose, the CDA is additionally extended to provide 2-D topography-profile and 3-D shape for each crater-candidate. The latter two are a performance problem because of the large number of crater-candidates in combination with the large number of attributes. As a solution, we developed a CDA architecture wherein it is possible to combine the SVM with a radial basis function (RBF) or any other kernel (for initial set of attributes), with the SVM with linear kernel (for the cases when 2-D and 3-D data are included as well). Another challenge is that, in addition to diversity of possible crater types, there are numerous morphological differences between the smallest (mostly very circular bowl-shaped craters) and the largest (multi-ring) impact

  7. Energy landscapes for a machine learning application to series data

    NASA Astrophysics Data System (ADS)

    Ballard, Andrew J.; Stevenson, Jacob D.; Das, Ritankar; Wales, David J.

    2016-03-01

    Methods developed to explore and characterise potential energy landscapes are applied to the corresponding landscapes obtained from optimisation of a cost function in machine learning. We consider neural network predictions for the outcome of local geometry optimisation in a triatomic cluster, where four distinct local minima exist. The accuracy of the predictions is compared for fits using data from single and multiple points in the series of atomic configurations resulting from local geometry optimisation and for alternative neural networks. The machine learning solution landscapes are visualised using disconnectivity graphs, and signatures in the effective heat capacity are analysed in terms of distributions of local minima and their properties.

  8. The evolution and practical application of machine translation system (1)

    NASA Astrophysics Data System (ADS)

    Tominaga, Isao; Sato, Masayuki

    This paper describes a development, practical applicatioin, problem of a system, evaluation of practical system, and development trend of machine translation. Most recent system contains next four problems. 1) the vagueness of a text, 2) a difference of the definition of the terminology between different language, 3) the preparing of a large-scale translation dictionary, 4) the development of a software for the logical inference. Machine translation system is already used practically in many industry fields. However, many problems are not solved. The implementation of an ideal system will be after 15 years. Also, this paper described seven evaluation items detailedly. This English abstract was made by Mu system.

  9. Energy landscapes for a machine learning application to series data.

    PubMed

    Ballard, Andrew J; Stevenson, Jacob D; Das, Ritankar; Wales, David J

    2016-03-28

    Methods developed to explore and characterise potential energy landscapes are applied to the corresponding landscapes obtained from optimisation of a cost function in machine learning. We consider neural network predictions for the outcome of local geometry optimisation in a triatomic cluster, where four distinct local minima exist. The accuracy of the predictions is compared for fits using data from single and multiple points in the series of atomic configurations resulting from local geometry optimisation and for alternative neural networks. The machine learning solution landscapes are visualised using disconnectivity graphs, and signatures in the effective heat capacity are analysed in terms of distributions of local minima and their properties.

  10. Programmable phase plate for tool modification in laser machining applications

    DOEpatents

    Thompson Jr., Charles A.; Kartz, Michael W.; Brase, James M.; Pennington, Deanna; Perry, Michael D.

    2004-04-06

    A system for laser machining includes a laser source for propagating a laser beam toward a target location, and a spatial light modulator having individual controllable elements capable of modifying a phase profile of the laser beam to produce a corresponding irradiance pattern on the target location. The system also includes a controller operably connected to the spatial light modulator for controlling the individual controllable elements. By controlling the individual controllable elements, the phase profile of the laser beam may be modified into a desired phase profile so as to produce a corresponding desired irradiance pattern on the target location capable of performing a machining operation on the target location.

  11. Characteristic Analysis of Vuilleumier Cycle Machine and Its Application to Air-Conditioning Heat Pump

    NASA Astrophysics Data System (ADS)

    Sekiya, Hiroshi

    The Vuilleumier (VM) cycle machine is realized as a regenerative and external-combustion machine in the same way as a Stirling (ST) cycle machine. In the VM cycle, heat enters the cyc1e from hot and cold temperature heat sources and is delivered to an intermediate temperature heat source by a working gas. In consequence of the theoretical cycle, output power is not produced. The VM cycle machine is made of the same elements as the ST cycle machine and also closely connected with the ST cycle machine in its working principle. By means of analysis using an isothermal model, it is found that the VM cycle machine is internally divided into a ST engine and a ST refrigerator. In addition, the calculated results by a simulation model based on a so-called 3rd-order method clarify that the VM cycle machine has different featuers from the ST cycle macine with regard to the working gas behavior, the energy flow and the performance depending on the revolution speed. Application of the VM cycle machine to a heat pump for heating and cooling takes effect on the environment and energy problems arising on a terrestrial scale. In reacent years, research and development have been making on the VM haet pumps.

  12. Design of piezo-based AVC system for machine tool applications

    NASA Astrophysics Data System (ADS)

    Aggogeri, F.; Al-Bender, F.; Brunner, B.; Elsaid, M.; Mazzola, M.; Merlo, A.; Ricciardi, D.; de la O Rodriguez, M.; Salvi, E.

    2013-03-01

    The goal of machine tools for Ultra High Precision Machining is to guarantee high specified performances and to maintain them over life cycle time. In this paper the design of an innovative mechatronic subsystem (platform) for Active Vibration Control (AVC) of Ultra High Precision micromilling Machines is presented. The platform integrates piezoelectric stack actuators and a novel sensor concept. During the machining process (e.g. milling), the contact between the cutting tool and the workpiece surface at the tool tip point generates chattering vibrations. Any vibration is recorded on the workpiece surface, directly affecting its roughness. Consequently, uncontrolled vibrations lead to poor surface finishing, unacceptable in high precision milling. The proposed Smart Platform aims to improve the surface finishing of the workpiece exploiting a broadband AVC strategy. The paper describes the steps throughout the design phase of the platform, beginning from the actuator/sensor criteria selection taking into account both performance and durability. The novel actuation principle and mechanism and the related FE analysis are also presented. Finally, an integrated mechatronic model able to predict in closed-loop the active damping and vibration-suppression capability of the integrated system is presented and simulation results are discussed.

  13. The 25th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    Sydnor, Richard L. (Editor)

    1994-01-01

    Papers in the following categories are presented: recent developments in rubidium, cesium, and hydrogen-based frequency standards, and in cryogenic and trapped-ion technology; international and transnational applications of precise time and time interval (PTTI) technology with emphasis on satellite laser tracking networks, GLONASS timing, intercomparison of national time scales and international telecommunication; applications of PTTI technology to the telecommunications, power distribution, platform positioning, and geophysical survey industries; application of PTTI technology to evolving military communications and navigation systems; and dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, LORAN, and synchronous communications satellites.

  14. The 26th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    Sydnor, Richard (Editor)

    1995-01-01

    This document is a compilation of technical papers presented at the 26th Annual PTTI Applications and Planning Meeting. Papers are in the following categories: (1) Recent developments in rubidium, cesium, and hydrogen-based frequency standards, and in cryogenic and trapped-ion technology; (2) International and transnational applications of Precise Time and Time Interval technology with emphasis on satellite laser tracking, GLONASS timing, intercomparison of national time scales and international telecommunications; (3) Applications of Precise Time and Time Interval technology to the telecommunications, power distribution, platform positioning, and geophysical survey industries; (4) Applications of PTTI technology to evolving military communications and navigation systems; and (5) Dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, LORAN, and synchronous communications satellites.

  15. Machine Learning Through Signature Trees. Applications to Human Speech.

    ERIC Educational Resources Information Center

    White, George M.

    A signature tree is a binary decision tree used to classify unknown patterns. An attempt was made to develop a computer program for manipulating signature trees as a general research tool for exploring machine learning and pattern recognition. The program was applied to the problem of speech recognition to test its effectiveness for a specific…

  16. Application of TRIZ approach to machine vibration condition monitoring problems

    NASA Astrophysics Data System (ADS)

    Cempel, Czesław

    2013-12-01

    Up to now machine condition monitoring has not been seriously approached by TRIZ1TRIZ= Russian acronym for Inventive Problem Solving System, created by G. Altshuller ca 50 years ago. users, and the knowledge of TRIZ methodology has not been applied there intensively. However, there are some introductory papers of present author posted on Diagnostic Congress in Cracow (Cempel, in press [11]), and Diagnostyka Journal as well. But it seems to be further need to make such approach from different sides in order to see, if some new knowledge and technology will emerge. In doing this we need at first to define the ideal final result (IFR) of our innovation problem. As a next we need a set of parameters to describe the problems of system condition monitoring (CM) in terms of TRIZ language and set of inventive principles possible to apply, on the way to IFR. This means we should present the machine CM problem by means of contradiction and contradiction matrix. When specifying the problem parameters and inventive principles, one should use analogy and metaphorical thinking, which by definition is not exact but fuzzy, and leads sometimes to unexpected results and outcomes. The paper undertakes this important problem again and brings some new insight into system and machine CM problems. This may mean for example the minimal dimensionality of TRIZ engineering parameter set for the description of machine CM problems, and the set of most useful inventive principles applied to given engineering parameter and contradictions of TRIZ.

  17. Interactions between science and precision engineering

    NASA Astrophysics Data System (ADS)

    Atkinson, D. P.; McClure, E. R.; Saito, T. T.

    1987-11-01

    The history of scientific progress is intertwined intimately with precision engineering. Precision engineering and science have synergistically interacted in stimulating each other to significant advances. Furthermore, tangible benefits to the quality of human life, through often unexpected industrial applications, occur. High energy lasers, astrophysical telescopes, and anamorphic optics, along with developments in ultraprecision machining and measurement, are discussed as examples of evolution in science and precision engineering. Possibilities for ultimate by-products for mankind's welfare are explored.

  18. Robust Extreme Learning Machine With its Application to Indoor Positioning.

    PubMed

    Lu, Xiaoxuan; Zou, Han; Zhou, Hongming; Xie, Lihua; Huang, Guang-Bin

    2016-01-01

    The increasing demands of location-based services have spurred the rapid development of indoor positioning system and indoor localization system interchangeably (IPSs). However, the performance of IPSs suffers from noisy measurements. In this paper, two kinds of robust extreme learning machines (RELMs), corresponding to the close-to-mean constraint, and the small-residual constraint, have been proposed to address the issue of noisy measurements in IPSs. Based on whether the feature mapping in extreme learning machine is explicit, we respectively provide random-hidden-nodes and kernelized formulations of RELMs by second order cone programming. Furthermore, the computation of the covariance in feature space is discussed. Simulations and real-world indoor localization experiments are extensively carried out and the results demonstrate that the proposed algorithms can not only improve the accuracy and repeatability, but also reduce the deviation and worst case error of IPSs compared with other baseline algorithms. PMID:26684258

  19. Spectral kurtosis for fault detection, diagnosis and prognostics of rotating machines: A review with applications

    NASA Astrophysics Data System (ADS)

    Wang, Yanxue; Xiang, Jiawei; Markert, Richard; Liang, Ming

    2016-01-01

    Condition-based maintenance via vibration signal processing plays an important role to reduce unscheduled machine downtime and avoid catastrophic accidents in industrial enterprises. Many machine faults, such as local defects in rotating machines, manifest themselves in the acquired vibration signals as a series of impulsive events. The spectral kurtosis (SK) technique extends the concept of kurtosis to that of a function of frequency that indicates how the impulsiveness of a signal. This work intends to review and summarize the recent research developments on the SK theories, for instance, short-time Fourier transform-based SK, kurtogram, adaptive SK and protrugram, as well as the corresponding applications in fault detection and diagnosis of the rotating machines. The potential prospects of prognostics using SK technique are also designated. Some examples have been presented to illustrate their performances. The expectation is that further research and applications of the SK technique will flourish in the future, especially in the fields of the prognostics.

  20. Applications of time-frequency analysis to signals from manufacturing and machine monitoring sensors

    SciTech Connect

    Atlas, L.E.; Narayanan, S.B.; Bernard, G.D.

    1996-09-01

    Manufacturing industries are now demanding substantial increases in flexibility, productivity and reliability from their process machines as well as increased quality and value of their products. One important strategy to support this goal is sensor-based, on-line, real-time evaluation of key characteristics of both machines and products, throughout the manufacturing process. Recent advances in time-frequency (TF) analysis are particularly well suited to extracting key vibrational characteristics from monitoring sensors. Thus this paper presents applications of TF analysis to several important manufacturing and machine monitoring tasks, to show the value of these forms of digital signal processing applied to manufacturing.

  1. Automata in random environments with application to machine intelligence

    SciTech Connect

    Wegman, E.J.; Gould, J.

    1982-09-01

    Computers and brains are modeled by finite and probabilistic automata, respectively. Probabilistic automata are known to be strictly more powerful than finite automata. The observation that the environment affects behavior of both computer and brain is made. Automata are then modeled in an environment. Theorem 1 shows that useful environmental models are those which are infinite sets. A probabilistic structure is placed on the environment set. Theorem 2 compares the behavior of finite (deterministic) and probabilistic automata in random environments. Several interpretations of theorem 2 are discussed which offer some insight into some mathematical limits of machine intelligence. 15 references.

  2. Fabrication of continuous flow microfluidics device with 3D electrode structures for high throughput DEP applications using mechanical machining.

    PubMed

    Zeinali, Soheila; Çetin, Barbaros; Oliaei, Samad Nadimi Bavil; Karpat, Yiğit

    2015-07-01

    Microfluidics is the combination of micro/nano fabrication techniques with fluid flow at microscale to pursue powerful techniques in controlling and manipulating chemical and biological processes. Sorting and separation of bio-particles are highly considered in diagnostics and biological analyses. Dielectrophoresis (DEP) has offered unique advantages for microfluidic devices. In DEP devices, asymmetric pair of planar electrodes could be employed to generate non-uniform electric fields. In DEP applications, facing 3D sidewall electrodes is considered to be one of the key solutions to increase device throughput due to the generated homogeneous electric fields along the height of microchannels. Despite the advantages, fabrication of 3D vertical electrodes requires a considerable challenge. In this study, two alternative fabrication techniques have been proposed for the fabrication of a microfluidic device with 3D sidewall electrodes. In the first method, both the mold and the electrodes are fabricated using high precision machining. In the second method, the mold with tilted sidewalls is fabricated using high precision machining and the electrodes are deposited on the sidewall using sputtering together with a shadow mask fabricated by electric discharge machining. Both fabrication processes are assessed as highly repeatable and robust. Moreover, the two methods are found to be complementary with respect to the channel height. Only the manipulation of particles with negative-DEP is demonstrated in the experiments, and the throughput values up to 105 particles / min is reached in a continuous flow. The experimental results are compared with the simulation results and the limitations on the fabrication techniques are also discussed.

  3. Application of Machine Learning to the Prediction of Vegetation Health

    NASA Astrophysics Data System (ADS)

    Burchfield, Emily; Nay, John J.; Gilligan, Jonathan

    2016-06-01

    This project applies machine learning techniques to remotely sensed imagery to train and validate predictive models of vegetation health in Bangladesh and Sri Lanka. For both locations, we downloaded and processed eleven years of imagery from multiple MODIS datasets which were combined and transformed into two-dimensional matrices. We applied a gradient boosted machines model to the lagged dataset values to forecast future values of the Enhanced Vegetation Index (EVI). The predictive power of raw spectral data MODIS products were compared across time periods and land use categories. Our models have significantly more predictive power on held-out datasets than a baseline. Though the tool was built to increase capacity to monitor vegetation health in data scarce regions like South Asia, users may include ancillary spatiotemporal datasets relevant to their region of interest to increase predictive power and to facilitate interpretation of model results. The tool can automatically update predictions as new MODIS data is made available by NASA. The tool is particularly well-suited for decision makers interested in understanding and predicting vegetation health dynamics in countries in which environmental data is scarce and cloud cover is a significant concern.

  4. Vision-Based People Detection System for Heavy Machine Applications

    PubMed Central

    Fremont, Vincent; Bui, Manh Tuan; Boukerroui, Djamal; Letort, Pierrick

    2016-01-01

    This paper presents a vision-based people detection system for improving safety in heavy machines. We propose a perception system composed of a monocular fisheye camera and a LiDAR. Fisheye cameras have the advantage of a wide field-of-view, but the strong distortions that they create must be handled at the detection stage. Since people detection in fisheye images has not been well studied, we focus on investigating and quantifying the impact that strong radial distortions have on the appearance of people, and we propose approaches for handling this specificity, adapted from state-of-the-art people detection approaches. These adaptive approaches nevertheless have the drawback of high computational cost and complexity. Consequently, we also present a framework for harnessing the LiDAR modality in order to enhance the detection algorithm for different camera positions. A sequential LiDAR-based fusion architecture is used, which addresses directly the problem of reducing false detections and computational cost in an exclusively vision-based system. A heavy machine dataset was built, and different experiments were carried out to evaluate the performance of the system. The results are promising, in terms of both processing speed and performance. PMID:26805838

  5. Geological applications of machine learning on hyperspectral remote sensing data

    NASA Astrophysics Data System (ADS)

    Tse, C. H.; Li, Yi-liang; Lam, Edmund Y.

    2015-02-01

    The CRISM imaging spectrometer orbiting Mars has been producing a vast amount of data in the visible to infrared wavelengths in the form of hyperspectral data cubes. These data, compared with those obtained from previous remote sensing techniques, yield an unprecedented level of detailed spectral resolution in additional to an ever increasing level of spatial information. A major challenge brought about by the data is the burden of processing and interpreting these datasets and extract the relevant information from it. This research aims at approaching the challenge by exploring machine learning methods especially unsupervised learning to achieve cluster density estimation and classification, and ultimately devising an efficient means leading to identification of minerals. A set of software tools have been constructed by Python to access and experiment with CRISM hyperspectral cubes selected from two specific Mars locations. A machine learning pipeline is proposed and unsupervised learning methods were implemented onto pre-processed datasets. The resulting data clusters are compared with the published ASTER spectral library and browse data products from the Planetary Data System (PDS). The result demonstrated that this approach is capable of processing the huge amount of hyperspectral data and potentially providing guidance to scientists for more detailed studies.

  6. Vision-Based People Detection System for Heavy Machine Applications.

    PubMed

    Fremont, Vincent; Bui, Manh Tuan; Boukerroui, Djamal; Letort, Pierrick

    2016-01-01

    This paper presents a vision-based people detection system for improving safety in heavy machines. We propose a perception system composed of a monocular fisheye camera and a LiDAR. Fisheye cameras have the advantage of a wide field-of-view, but the strong distortions that they create must be handled at the detection stage. Since people detection in fisheye images has not been well studied, we focus on investigating and quantifying the impact that strong radial distortions have on the appearance of people, and we propose approaches for handling this specificity, adapted from state-of-the-art people detection approaches. These adaptive approaches nevertheless have the drawback of high computational cost and complexity. Consequently, we also present a framework for harnessing the LiDAR modality in order to enhance the detection algorithm for different camera positions. A sequential LiDAR-based fusion architecture is used, which addresses directly the problem of reducing false detections and computational cost in an exclusively vision-based system. A heavy machine dataset was built, and different experiments were carried out to evaluate the performance of the system. The results are promising, in terms of both processing speed and performance. PMID:26805838

  7. 27th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    Sydnor, Richard L. (Editor)

    1996-01-01

    This document is a compilation of technical papers presented at the 27th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting, held November 29 - December 1, 1995 at San Diego, CA. Papers are in the following categories: Recent developments in rubidium, cesium, and hydrogen-based frequency standards; and in cryogenic and trapped-ion technology; International and transnational applications of PTTI technology with emphasis on satellite laser tracking, GLONASS timing, intercomparison of national time scales and international telecommunications; Applications of PTTI technology to the telecommunications, power distribution, platform positioning, and geophysical survey industries; Applications of PTTI technology to evolving military communications and navigation systems; and Dissemination of precise time and frequency by means of Global Positioning System (GPS), Global Satellite Navigation System (GLONASS), MILSTAR, LORAN, and synchronous communications satellites.

  8. The 24th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    Sydnor, Richard L.

    1993-01-01

    A compilation of technical papers presented at the 24th Precise Time and Time Interval (PTTI) Applications and Planning Meeting held in Dec. 1992 is presented. Papers are in the following categories: recent developments in rubidium, cesium, and hydrogen-based frequency standards, and in cryogenic and trapped-ion technology; international and transnational applications of PTTI technology with emphasis on satellite laser tracking networks, GLONASS timing, intercomparison of national time scales, and international telecommunications; applications of PTTI technology to the telecommunications, power distribution, and platform positioning, and geophysical survey industries; applications of PTTI technology to evolving military communications and navigation systems; and dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, Loran, and synchronous communications satellites.

  9. Proceedings of the 23rd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    Sydnor, Richard L. (Editor)

    1992-01-01

    A compilation of technical papers, from the 23rd annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting, is presented. Papers were given in the following categories: (1) developments in rubidium, cesium, and hydrogen-based frequency standards, and in cryogenic and trapped-ion technology; (2) international and transnational applications of PTTI technology with emphasis on satellite laser tracking networks, GLONASS timing, comparison of national time scales and international communications; (3) applications of PTTI technology to the telecommunications, power distribution, platform positioning, and geophysical survey industries; (4) applications of PTTI technology to evolving military communications and navigation systems; and (5) dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, Loran, and synchronous communications satellites.

  10. Proceedings of the 23rd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    SciTech Connect

    Sydnor, R.L.

    1992-07-01

    A compilation of technical papers, from the 23rd annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting, is presented. Papers were given in the following categories: (1) developments in rubidium, cesium, and hydrogen-based frequency standards, and in cryogenic and trapped-ion technology; (2) international and transnational applications of PTTI technology with emphasis on satellite laser tracking networks, GLONASS timing, comparison of national time scales and international communications; (3) applications of PTTI technology to the telecommunications, power distribution, platform positioning, and geophysical survey industries; (4) applications of PTTI technology to evolving military communications and navigation systems; and (5) dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, Loran, and synchronous communications satellites.

  11. Remote sensing with simulated unmanned aircraft systems for precision agriculture applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An important application of unmanned aircraft systems (UAS) may be remote-sensing for precision agriculture, because of its ability to acquire images with very small pixel sizes from low altitude flights. The objective of this study was to compare pixel sampling with plot-scale metrics for the remo...

  12. Proceedings of the Thirteenth Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    Wardrip, S. C.

    1982-01-01

    Proceedings of an annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting are summarized. A transparent view of the state-of-the-art, an opportunity to express needs, a view of important future trends, and a review of relevant past accomplishments were considered for PTTI managers, systems engineers, and program planner. Specific aims were: to provide PTTI users with new and useful applications, procedures, and techniques; to allow the PTTI researcher to better assess fruitful directions for research efforts.

  13. New photolithography stepping machine

    SciTech Connect

    Hale, L.; Klingmann, J.; Markle, D.

    1995-03-08

    A joint development project to design a new photolithography steeping machine capable of 150 nanometer overlay accuracy was completed by Ultratech Stepper and the Lawrence Livermore National Laboratory. The principal result of the project is a next-generation product that will strengthen the US position in step-and-repeat photolithography. The significant challenges addressed and solved in the project are the subject of this report. Design methods and new devices that have broader application to precision machine design are presented in greater detail while project specific information serves primarily as background and motivation.

  14. Development of Fractal Pattern Making Application using L-System for Enhanced Machine Controller

    NASA Astrophysics Data System (ADS)

    Gunawan, Alexander A. S.; Linggarjati, Jimmy; Wijaya, Yandi

    2014-03-01

    One big issue facing the industry today is an automated machine lack of flexibility for customization because it is designed by the manufacturers based on certain standards. In this research, it is developed customized application software for CNC (Computer Numerically Controlled) machines using open source platform. The application is enable us to create designs by means of fractal patterns using L-System, developed by turtle geometry interpretation and Python programming languages. The result of the application is the G-Code of fractal pattern formed by the method of L-System. In the experiment on the CNC machine, the G-Code of fractal pattern which involving the branching structure has been able to run well.

  15. Application of TPM indicators for analyzing work time of machines used in the pressure die casting

    NASA Astrophysics Data System (ADS)

    Borkowski, Stanisław; Czajkowska, Agnieszka; Stasiak-Betlejewska, Renata; Borade, Atul B.

    2014-05-01

    The article presents the application of total productive maintenance (TPM) to analyze the working time indicators of casting machines with particular emphasis on failures and unplanned downtime to reduce the proportion of emergency operation for preventive maintenance and diagnostics. The article presents that the influence of individual factors of complex machinery maintenance (TPM) is different and depends on the machines' modernity level. In an original way, by using correlation graphs, research findings on the impact of individual TPM factors on the castings quality were presented and interpreted. The examination results conducted for machines with varying modernity degrees allowed to determine changes within the impact of individual TPM factors depending on machine parameters. These results provide a rich source of information for the improvement processes on casting quality of the foundry industry that satisfies the automotive industry demand.

  16. Tunnel boring machine applications; Yucca Mountain Exploratory Studies Facility

    SciTech Connect

    Bhattacharyya, K.K.; McDonald, R.; Saunders, R.S.

    1992-11-01

    This paper reports that characterization of Yucca Mountain for a potential repository requires construction of an underground Exploratory Studies Facility (ESF). Mechanical excavating methods have been proposed for construction of the ESF as they offer a number of advantages over drilling and blasting at the Yucca Mountain site, including; less ground disturbance and therefore a potential for less adverse effects on the integrity of the site, creation of a more stable excavation cross section requiring less ground support, and an inherently safer and cleaner working environment. The tunnel boring machine (TBM) provides a proven technology for excavating the welded and unwelded Yucca Mountain tuffs. The access ramps and main underground tunnels form the largest part of the ESF underground construction work, and have been designed for excavation by TBM.

  17. Application of Support Vector Machine to Forex Monitoring

    NASA Astrophysics Data System (ADS)

    Kamruzzaman, Joarder; Sarker, Ruhul A.

    Previous studies have demonstrated superior performance of artificial neural network (ANN) based forex forecasting models over traditional regression models. This paper applies support vector machines to build a forecasting model from the historical data using six simple technical indicators and presents a comparison with an ANN based model trained by scaled conjugate gradient (SCG) learning algorithm. The models are evaluated and compared on the basis of five commonly used performance metrics that measure closeness of prediction as well as correctness in directional change. Forecasting results of six different currencies against Australian dollar reveal superior performance of SVM model using simple linear kernel over ANN-SCG model in terms of all the evaluation metrics. The effect of SVM parameter selection on prediction performance is also investigated and analyzed.

  18. The 22nd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    Sydnor, Richard L. (Editor)

    1990-01-01

    Papers presented at the 22nd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting are compiled. The following subject areas are covered: Rb, Cs, and H-based frequency standards and cryogenic and trapped-ion technology; satellite laser tracking networks, GLONASS timing, intercomparison of national time scales and international telecommunications; telecommunications, power distribution, platform positioning, and geophysical survey industries; military communications and navigation systems; and dissemination of precise time and frequency by means of GPS, GLONASS, MILSTAR, LORAN, and synchronous communication satellites.

  19. The 22nd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    SciTech Connect

    Sydnor, R.L.

    1990-05-01

    Papers presented at the 22nd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting are compiled. The following subject areas are covered: Rb, Cs, and H-based frequency standards and cryogenic and trapped-ion technology; satellite laser tracking networks, GLONASS timing, intercomparison of national time scales and international telecommunications; telecommunications, power distribution, platform positioning, and geophysical survey industries; military communications and navigation systems; and dissemination of precise time and frequency by means of GPS, GLONASS, MIL<550>STAR, LORAN, and synchronous communication satellites.

  20. e-Learning Application for Machine Maintenance Process using Iterative Method in XYZ Company

    NASA Astrophysics Data System (ADS)

    Nurunisa, Suaidah; Kurniawati, Amelia; Pramuditya Soesanto, Rayinda; Yunan Kurnia Septo Hediyanto, Umar

    2016-02-01

    XYZ Company is a company based on manufacturing part for airplane, one of the machine that is categorized as key facility in the company is Millac 5H6P. As a key facility, the machines should be assured to work well and in peak condition, therefore, maintenance process is needed periodically. From the data gathering, it is known that there are lack of competency from the maintenance staff to maintain different type of machine which is not assigned by the supervisor, this indicate that knowledge which possessed by maintenance staff are uneven. The purpose of this research is to create knowledge-based e-learning application as a realization from externalization process in knowledge transfer process to maintain the machine. The application feature are adjusted for maintenance purpose using e-learning framework for maintenance process, the content of the application support multimedia for learning purpose. QFD is used in this research to understand the needs from user. The application is built using moodle with iterative method for software development cycle and UML Diagram. The result from this research is e-learning application as sharing knowledge media for maintenance staff in the company. From the test, it is known that the application make maintenance staff easy to understand the competencies.

  1. Proceedings of the 30th Annual Precise Time and Time Interval (PTTI) Systems and Applications Meeting

    NASA Technical Reports Server (NTRS)

    Breakiron, Lee A. (Editor)

    1999-01-01

    This document is a compilation of technical papers presented at the 30th Annual Precise Time and Time Interval (PTTI) Systems and Applications Meeting held 1-3 December 1998 at the Hyatt Regency Hotel at Reston Town Center, Reston, Virginia. Papers are in the following categories: 1) Recent developments in rubidium, cesium, and hydrogen-based atomic frequency standards, and in trapped-ion and space clock technology; 2) National and international applications of PTTI technology with emphasis on GPS and GLONASS timing, atomic time scales, and telecommunications; 3) Applications of PTTI technology to evolving military navigation and communication systems; geodesy; aviation; and pulsars; and 4) Dissemination of precise time and frequency by means of GPS, geosynchronous communication satellites, computer networks, WAAS, and LORAN.

  2. Space Applications of Automation, Robotics and Machine Intelligence Systems (ARAMIS). Volume 1: Executive Summary

    NASA Technical Reports Server (NTRS)

    Miller, R. H.; Minsky, M. L.; Smith, D. B. S.

    1982-01-01

    Potential applications of automation, robotics, and machine intelligence systems (ARAMIS) to space activities, and to their related ground support functions are explored. The specific tasks which will be required by future space projects are identified. ARAMIS options which are candidates for those space project tasks and the relative merits of these options are defined and evaluated. Promising applications of ARAMIS and specific areas for further research are identified. The ARAMIS options defined and researched by the study group span the range from fully human to fully machine, including a number of intermediate options (e.g., humans assisted by computers, and various levels of teleoperation). By including this spectrum, the study searches for the optimum mix of humans and machines for space project tasks.

  3. Precise calibration of a GNSS antenna array for adaptive beamforming applications.

    PubMed

    Daneshmand, Saeed; Sokhandan, Negin; Zaeri-Amirani, Mohammad; Lachapelle, Gérard

    2014-05-30

    The use of global navigation satellite system (GNSS) antenna arrays for applications such as interference counter-measure, attitude determination and signal-to-noise ratio (SNR) enhancement is attracting significant attention. However, precise antenna array calibration remains a major challenge. This paper proposes a new method for calibrating a GNSS antenna array using live signals and an inertial measurement unit (IMU). Moreover, a second method that employs the calibration results for the estimation of steering vectors is also proposed. These two methods are applied to the receiver in two modes, namely calibration and operation. In the calibration mode, a two-stage optimization for precise calibration is used; in the first stage, constant uncertainties are estimated while in the second stage, the dependency of each antenna element gain and phase patterns to the received signal direction of arrival (DOA) is considered for refined calibration. In the operation mode, a low-complexity iterative and fast-converging method is applied to estimate the satellite signal steering vectors using the calibration results. This makes the technique suitable for real-time applications employing a precisely calibrated antenna array. The proposed calibration method is applied to GPS signals to verify its applicability and assess its performance. Furthermore, the data set is used to evaluate the proposed iterative method in the receiver operation mode for two different applications, namely attitude determination and SNR enhancement.

  4. Precise calibration of a GNSS antenna array for adaptive beamforming applications.

    PubMed

    Daneshmand, Saeed; Sokhandan, Negin; Zaeri-Amirani, Mohammad; Lachapelle, Gérard

    2014-01-01

    The use of global navigation satellite system (GNSS) antenna arrays for applications such as interference counter-measure, attitude determination and signal-to-noise ratio (SNR) enhancement is attracting significant attention. However, precise antenna array calibration remains a major challenge. This paper proposes a new method for calibrating a GNSS antenna array using live signals and an inertial measurement unit (IMU). Moreover, a second method that employs the calibration results for the estimation of steering vectors is also proposed. These two methods are applied to the receiver in two modes, namely calibration and operation. In the calibration mode, a two-stage optimization for precise calibration is used; in the first stage, constant uncertainties are estimated while in the second stage, the dependency of each antenna element gain and phase patterns to the received signal direction of arrival (DOA) is considered for refined calibration. In the operation mode, a low-complexity iterative and fast-converging method is applied to estimate the satellite signal steering vectors using the calibration results. This makes the technique suitable for real-time applications employing a precisely calibrated antenna array. The proposed calibration method is applied to GPS signals to verify its applicability and assess its performance. Furthermore, the data set is used to evaluate the proposed iterative method in the receiver operation mode for two different applications, namely attitude determination and SNR enhancement. PMID:24887043

  5. Precise Calibration of a GNSS Antenna Array for Adaptive Beamforming Applications

    PubMed Central

    Daneshmand, Saeed; Sokhandan, Negin; Zaeri-Amirani, Mohammad; Lachapelle, Gérard

    2014-01-01

    The use of global navigation satellite system (GNSS) antenna arrays for applications such as interference counter-measure, attitude determination and signal-to-noise ratio (SNR) enhancement is attracting significant attention. However, precise antenna array calibration remains a major challenge. This paper proposes a new method for calibrating a GNSS antenna array using live signals and an inertial measurement unit (IMU). Moreover, a second method that employs the calibration results for the estimation of steering vectors is also proposed. These two methods are applied to the receiver in two modes, namely calibration and operation. In the calibration mode, a two-stage optimization for precise calibration is used; in the first stage, constant uncertainties are estimated while in the second stage, the dependency of each antenna element gain and phase patterns to the received signal direction of arrival (DOA) is considered for refined calibration. In the operation mode, a low-complexity iterative and fast-converging method is applied to estimate the satellite signal steering vectors using the calibration results. This makes the technique suitable for real-time applications employing a precisely calibrated antenna array. The proposed calibration method is applied to GPS signals to verify its applicability and assess its performance. Furthermore, the data set is used to evaluate the proposed iterative method in the receiver operation mode for two different applications, namely attitude determination and SNR enhancement. PMID:24887043

  6. Florida Vocational Program Guide for Basic Precision Machining, Precision Machining.

    ERIC Educational Resources Information Center

    University of South Florida, Tampa. Dept. of Adult and Vocational Education.

    This program guide has been developed to provide information that will be useful to local school district and community college administrators, instructors, program advisory committee members, regional coordinating councils, and others charged with the responsibility of offering vocational education programs in Florida. It identifies the major…

  7. Physiological cognitive state assessment: applications for designing effective human-machine systems.

    PubMed

    Estepp, Justin R; Christensen, James C

    2011-01-01

    Significant growth in the field of neuroscience has occurred over the last decade such that new application areas for basic research techniques are opening up to practitioners in many other areas. Of particular interest to many is the principle of neuroergonomics, by which the traditional work in neuroscience and its related topics can be applied to non-traditional areas such as human-machine system design. While work in neuroergonomics certainly predates the use of the term in the literature (previously identified by others as applied neuroscience, operational neuroscience, etc.), there is great promise in the larger framework that is represented by the general context of the terminology. Here, we focus on the very specific concept that principles in brain-computer interfaces, neural prosthetics and the larger realm of machine learning using physiological inputs can be applied directly to the design and implementation of augmented human-machine systems. Indeed, work in this area has been ongoing for more than 25 years with very little cross-talk and collaboration between clinical and applied researchers. We propose that, given increased interest in augmented human-machine systems based on cognitive state, further progress will require research in the same vein as that being done in the aforementioned communities, and that all researchers with a vested interest in physiologically-based machine learning techniques can benefit from increased collaboration. We thereby seek to describe the current state of cognitive state assessment in human-machine systems, the problems and challenges faced, and the tightly-coupled relationship with other research areas. This supports the larger work of the Cognitive State Assessment 2011 Competition by setting the stage for the purpose of the session by showing the need to increase research in the machine learning techniques used by practitioners of augmented human-machine system design.

  8. Melt-growth bulk superconductors and application to an axial-gap-type rotating machine

    NASA Astrophysics Data System (ADS)

    Zhang, Yufeng; Zhou, Difan; Ida, Tetsuya; Miki, Motohiro; Izumi, Mitsuru

    2016-04-01

    The present manuscript addresses key issues in the course of our study of materials processing of bulk high-temperature superconductors, trapped flux and its application to a prototype axial-gap-type rotating machine. The TUMSAT group has conducted a series of studies since 2003 on the growth of GdBa2Cu3O7-δ bulk material and its application in a compact low-speed high-torque rotating machine. In the stage of material growth, gaining the advantage of a large motive torque density requires large integrated flux in the motor/generators. A large grain surface might be required with sophisticated techniques for the melt-growth texture in the bulk with optimal flux pinning. In the second stage, the in situ magnetization procedure for bulk superconductors in the applied machine is a crucial part of the technology. Pulsed current excitation by using an armature copper winding has magnetized field pole bulks on the rotor. The axial-gap flux synchronous machine studied in the past decade is a condensed technology and indicates that further scientific development is required for a future compact machine to be superior to conventional ones in accordance with the cryogenic periphery and flux stabilization.

  9. A Bright Future for Precision Medicine: Advances in Fluorescent Chemical Probe Design and Their Clinical Application.

    PubMed

    Garland, Megan; Yim, Joshua J; Bogyo, Matthew

    2016-01-21

    The Precision Medicine Initiative aims to use advances in basic and clinical research to develop therapeutics that selectively target and kill cancer cells. Under the same doctrine of precision medicine, there is an equally important need to visualize these diseased cells to enable diagnosis, facilitate surgical resection, and monitor therapeutic response. Therefore, there is a great opportunity for chemists to develop chemically tractable probes that can image cancer in vivo. This review focuses on recent advances in the development of optical probes, as well as their current and future applications in the clinical management of cancer. The progress in probe development described here suggests that optical imaging is an important and rapidly developing field of study that encourages continued collaboration among chemists, biologists, and clinicians to further refine these tools for interventional surgical imaging, as well as for diagnostic and therapeutic applications. PMID:26933740

  10. Application of support vector machines and relevance vector machines in predicting uniaxial compressive strength of volcanic rocks

    NASA Astrophysics Data System (ADS)

    Ceryan, Nurcihan

    2014-12-01

    The uniaxial compressive strength (UCS) of intact rocks is an important and pertinent property for characterizing a rock mass. It is known that standard UCS tests are destructive, expensive and time-consuming task, which is particularly true for thinly bedded, highly fractured, foliated, highly porous and weak rocks. Consequently, prediction models have become an attractive alternative for engineering geologists. In the last several years, a new, alternative kernel-based technique, support vector machines (SVMs), has been popular in modeling studies. Despite superior SVM performance, this technique has certain significant, practical drawbacks. Hence, the relevance vector machines (RVMs) approach has been proposed to recast the main ideas underlying SVMs in a Bayesian context. The primary purpose of this study is to examine the applicability and capability of RVM and SVM models for predicting the UCS of volcanic rocks from NE Turkey and comparing its performance with ANN models. In these models, the porosity and P-durability index representing microstructural variables are the input parameters. The study results indicate that these methods can successfully predict the UCS for the volcanic rocks. The SVM and RVM performed better than the ANN model. When these kernel based models are considered, RVM model found successful in terms of statistical performance criterions (e.g., performance index, PI values for training and testing data are computed as 1.579 and 1.449). These values for SVM are 1.509 and 1.307. Although SVM and RVM models are powerful techniques, the RVM run time was considerably faster, and it yielded the highest accuracy.

  11. Application of Learning Machines and Combinatorial Algorithms in Water Resources Management and Hydrologic Sciences

    SciTech Connect

    Khalil, Abedalrazq F.; Kaheil, Yasir H.; Gill, Kashif; Mckee, Mac

    2010-01-01

    Contemporary and water resources engineering and management rely increasingly on pattern recognition techniques that have the ability to capitalize on the unrelenting accumulation of data that is made possible by modern information technology and remote sensing methods. In response to the growing information needs of modern water systems, advanced computational models and tools have been devised to identify and extract relevant information from the mass of data that is now available. This chapter presents innovative applications from computational learning science within the fields of hydrology, hydrogeology, hydroclimatology, and water management. The success of machine learning is evident from the growing number of studies involving the application of Artificial Neural Networks (ANN), Support Vector Machines (SVM), Relevance Vector Machines (RVM), and Locally Weighted Projection Regression (LWPR) to address various issues in hydrologic sciences. The applications that will be discussed within the chapter employ the abovementioned machine learning techniques for intelligent modeling of reservoir operations, temporal downscaling of precipitation, spatial downscaling of soil moisture and evapotranspiration, comparisons of various techniques for groundwater quality modeling, and forecasting of chaotic time series behavior. Combinatorial algorithms to capture the intrinsic complexities in the modeled phenomena and to overcome disparate scales are developed; for example, learning machines have been coupled with geostatistical techniques, non-homogenous hidden Markov models, wavelets, and evolutionary computing techniques. This chapter does not intend to be exhaustive; it reviews the progress that has been made over the past decade in the use of learning machines in applied hydrologic sciences and presents a summary of future needs and challenges for further advancement of these methods.

  12. Precision machining of steel decahedrons

    NASA Technical Reports Server (NTRS)

    Abernathy, W. J.; Sealy, J. R.

    1972-01-01

    Production of highly accurate decahedron prisms from hardened stainless steel is discussed. Prism is used to check angular alignment of mounting pads of strapdown inertial guidance system. Accuracies obtainable using recommended process and details of operation are described. Photographic illustration of production device is included.

  13. Techniques and applications for binaural sound manipulation in human-machine interfaces

    NASA Technical Reports Server (NTRS)

    Begault, Durand R.; Wenzel, Elizabeth M.

    1990-01-01

    The implementation of binaural sound to speech and auditory sound cues (auditory icons) is addressed from both an applications and technical standpoint. Techniques overviewed include processing by means of filtering with head-related transfer functions. Application to advanced cockpit human interface systems is discussed, although the techniques are extendable to any human-machine interface. Research issues pertaining to three-dimensional sound displays under investigation at the Aerospace Human Factors Division at NASA Ames Research Center are described.

  14. Techniques and applications for binaural sound manipulation in human-machine interfaces

    NASA Technical Reports Server (NTRS)

    Begault, Durand R.; Wenzel, Elizabeth M.

    1992-01-01

    The implementation of binaural sound to speech and auditory sound cues (auditory icons) is addressed from both an applications and technical standpoint. Techniques overviewed include processing by means of filtering with head-related transfer functions. Application to advanced cockpit human interface systems is discussed, although the techniques are extendable to any human-machine interface. Research issues pertaining to three-dimensional sound displays under investigation at the Aerospace Human Factors Division at NASA Ames Research Center are described.

  15. Machine learning applications in proteomics research: how the past can boost the future.

    PubMed

    Kelchtermans, Pieter; Bittremieux, Wout; De Grave, Kurt; Degroeve, Sven; Ramon, Jan; Laukens, Kris; Valkenborg, Dirk; Barsnes, Harald; Martens, Lennart

    2014-03-01

    Machine learning is a subdiscipline within artificial intelligence that focuses on algorithms that allow computers to learn solving a (complex) problem from existing data. This ability can be used to generate a solution to a particularly intractable problem, given that enough data are available to train and subsequently evaluate an algorithm on. Since MS-based proteomics has no shortage of complex problems, and since publicly available data are becoming available in ever growing amounts, machine learning is fast becoming a very popular tool in the field. We here therefore present an overview of the different applications of machine learning in proteomics that together cover nearly the entire wet- and dry-lab workflow, and that address key bottlenecks in experiment planning and design, as well as in data processing and analysis. PMID:24323524

  16. Light-driven artificial molecular machines

    NASA Astrophysics Data System (ADS)

    Zheng, Yue Bing; Hao, Qingzhen; Yang, Ying-Wei; Kiraly, Brian; Chiang, I.-Kao; Huang, Tony Jun

    2010-08-01

    Artificial molecular machines represent a growing field of nanoscience and nanotechnology. Stimulated by chemical reagents, electricity, or light, artificial molecular machines exhibit precisely controlled motion at the molecular level; with this ability molecular machines have the potential to make significant impacts in numerous engineering applications. Compared with molecular machines powered by chemical or electrical energy, light-driven molecular machines have several advantages: light can be switched much faster, work without producing chemical waste, and be used for dual purposes-inducing (writing) as well as detecting (reading) molecular motions. The following issues are significant for light-driven artificial molecular machines in the following aspects: their chemical structures, motion mechanisms, assembly and characterization on solid-state surfaces. Applications in different fields of nanotechnology such as molecular electronics, nano-electro-mechanical systems (NEMS), nanophotonics, and nanomedicine are envisaged.

  17. Two-axis Beam Steering Mirror Control system for Precision Pointing and Tracking Applications

    SciTech Connect

    Ulander, Klaus

    2006-01-01

    Precision pointing and tracking of laser beams is critical in numerous military and industrial applications. This is particularly true for systems requiring atmospheric beam propagation. Such systems are plagued by environmental influences which cause the optical signal to break up and wander. Example applications include laser communications, precision targeting, active imaging, chemical remote sensing, and laser vibrometry. The goal of this project is to build a beam steering system using a two-axis mirror to maintain precise pointing control. Ultimately, position control to 0.08% accuracy (40 {micro}rad) with a bandwidth of 200 Hz is desired. The work described encompasses evaluation of the instrumentation system and the subsequent design and implementation of an analog electronic controller for a two-axis mirror used to steer the beam. The controller operates over a wide temperature range, through multiple mirror resonances, and is independent of specific mirrors. The design was built and successfully fielded in a Lawrence Livermore National Laboratory free-space optics experiment. All measurements and performance parameters are derived from measurements made on actual hardware that was built and field tested. In some cases, specific design details have been omitted that involve proprietary information pertaining to Lawrence Livermore National Laboratory patent positions and claims. These omissions in no way impact the general validity of the work or concepts presented in this thesis.

  18. Sliding mode control of magnetic suspensions for precision pointing and tracking applications

    NASA Technical Reports Server (NTRS)

    Misovec, Kathleen M.; Flynn, Frederick J.; Johnson, Bruce G.; Hedrick, J. Karl

    1991-01-01

    A recently developed nonlinear control method, sliding mode control, is examined as a means of advancing the achievable performance of space-based precision pointing and tracking systems that use nonlinear magnetic actuators. Analytic results indicate that sliding mode control improves performance compared to linear control approaches. In order to realize these performance improvements, precise knowledge of the plant is required. Additionally, the interaction of an estimating scheme and the sliding mode controller has not been fully examined in the literature. Estimation schemes were designed for use with this sliding mode controller that do not seriously degrade system performance. The authors designed and built a laboratory testbed to determine the feasibility of utilizing sliding mode control in these types of applications. Using this testbed, experimental verification of the authors' analyses is ongoing.

  19. Recent Applications Of Metal Matrix Composites In Precision Instruments And Optical Systems

    NASA Astrophysics Data System (ADS)

    Mohn, Walter R.; Vukobratovich, Daniel

    1988-02-01

    This paper describes three unique metal matrix composite (MMC) material systems that have been developed for use in dimensionally stable platforms, precision mechanical systems, and lightweight reflective optics. These engineered materials, consisting of aluminum alloys reinforced with fine particles of silicon carbide, offer distinctive performance advantages over conventional metals, including greater specific stiffness, higher strength, and better resistance to compressive microcreep. Weighing about the same as aluminum, certain grades of these MMC materials are isotropic and have excellent thermal conductivity, and they can be tailored to match the coefficients of thermal expansion of other materials, including beryllium, stainless steel, and electroless nickel. Such flexibilities in establishing material properties and characteristics present new opportunities to the designer in producing weight-critical, precision hardware. Practical applications of MMC materials in advanced guidance equipment and lightweight optical assemblies are presented and discussed.

  20. Testing and application of a viscous passive damper for use in precision truss structures

    NASA Technical Reports Server (NTRS)

    Trubert, M.; Fanson, J.; Davis, P.; Anderson, E.

    1991-01-01

    A passive damping device intended to replace individual struts in precision truss structures for space applications is described. The theory of operation of the D-Strut device is detailed, and simple five- and three-parameter models are derived. Results from tests conducted to characterize the D-Strut at submicron displacement levels are reporeted. The incorporation of a strut in a precision truss testbed is described. Parameters determined from the component-level tests are used in a finite element model of the truss, and damping augmentation is predicted. Using the simple three-parameter model, a damper is selected for multiple placement in a separate optical interferometer truss testbed. The effect of the addition of the damper struts is illustrated analytically in a model of the structure. Finally, an improved Arched Flexure D-Strut that is expected to provide higher loss factors, and is currently under development, is described.

  1. True RGB line scan camera for color machine vision applications

    NASA Astrophysics Data System (ADS)

    Lemstrom, Guy F.

    1994-11-01

    In this paper a true RGB 3-chip color line scan camera is described. The camera was mainly developed for accurate color measuring in industrial applications. Due to the camera's modularity it's also possible to use it as a B/W-camera. The color separation is made with a RGB-beam splitter. The CCD linear arrays are fixed with a high accuracy to the beam splitters output in order to match the pixels of the three different CCDs on each other. This makes the color analyses simple compared to color line arrays where line or pixel matching has to be done. The beam splitter can be custom made to separate spectral components other than standard RGB. The spectral range is from 200 to 1000 nm for most CCDs and two or three spectral areas can be separately measured with the beam splitter. The camera is totally digital and has a 16-bit parallel computer interface to communicate with a signal processing board. Because of the open architecture of the camera it's possible for the customer to design a board with some special functions handling the preprocessing of the data (for example RGB - HSI conversion). The camera can also be equipped with a high speed CPU-board with enough local memory to do some image processing inside the camera before sending the data forward. The camera has been used in real industrial applications and has proven that its high resolution and high dynamic range can be used to measure color differences of small amounts to separate or grade objects such as minerals, food or other materials that can't be measured with a black and white camera.

  2. Semi-supervised least squares support vector machine algorithm: application to offshore oil reservoir

    NASA Astrophysics Data System (ADS)

    Luo, Wei-Ping; Li, Hong-Qi; Shi, Ning

    2016-06-01

    At the early stages of deep-water oil exploration and development, fewer and further apart wells are drilled than in onshore oilfields. Supervised least squares support vector machine algorithms are used to predict the reservoir parameters but the prediction accuracy is low. We combined the least squares support vector machine (LSSVM) algorithm with semi-supervised learning and established a semi-supervised regression model, which we call the semi-supervised least squares support vector machine (SLSSVM) model. The iterative matrix inversion is also introduced to improve the training ability and training time of the model. We use the UCI data to test the generalization of a semi-supervised and a supervised LSSVM models. The test results suggest that the generalization performance of the LSSVM model greatly improves and with decreasing training samples the generalization performance is better. Moreover, for small-sample models, the SLSSVM method has higher precision than the semi-supervised K-nearest neighbor (SKNN) method. The new semisupervised LSSVM algorithm was used to predict the distribution of porosity and sandstone in the Jingzhou study area.

  3. Robustness of thermal error compensation model of CNC machine tool

    NASA Astrophysics Data System (ADS)

    Lang, Xianli; Miao, Enming; Gong, Yayun; Niu, Pengcheng; Xu, Zhishang

    2013-01-01

    Thermal error is the major factor in restricting the accuracy of CNC machining. The modeling accuracy is the key of thermal error compensation which can achieve precision machining of CNC machine tool. The traditional thermal error compensation models mostly focus on the fitting accuracy without considering the robustness of the models, it makes the research results into practice is difficult. In this paper, the experiment of model robustness is done in different spinde speeds of leaderway V-450 machine tool. Combining fuzzy clustering and grey relevance selects temperature-sensitive points of thermal error. Using multiple linear regression model (MLR) and distributed lag model (DL) establishes model of the multi-batch experimental data and then gives robustness analysis, demonstrates the difference between fitting precision and prediction precision in engineering application, and provides a reference method to choose thermal error compensation model of CNC machine tool in the practical engineering application.

  4. Developing a New Wireless Sensor Network Platform and Its Application in Precision Agriculture

    PubMed Central

    Aquino-Santos, Raúl; González-Potes, Apolinar; Edwards-Block, Arthur; Virgen-Ortiz, Raúl Alejandro

    2011-01-01

    Wireless sensor networks are gaining greater attention from the research community and industrial professionals because these small pieces of “smart dust” offer great advantages due to their small size, low power consumption, easy integration and support for “green” applications. Green applications are considered a hot topic in intelligent environments, ubiquitous and pervasive computing. This work evaluates a new wireless sensor network platform and its application in precision agriculture, including its embedded operating system and its routing algorithm. To validate the technological platform and the embedded operating system, two different routing strategies were compared: hierarchical and flat. Both of these routing algorithms were tested in a small-scale network applied to a watermelon field. However, we strongly believe that this technological platform can be also applied to precision agriculture because it incorporates a modified version of LORA-CBF, a wireless location-based routing algorithm that uses cluster-based flooding. Cluster-based flooding addresses the scalability concerns of wireless sensor networks, while the modified LORA-CBF routing algorithm includes a metric to monitor residual battery energy. Furthermore, results show that the modified version of LORA-CBF functions well with both the flat and hierarchical algorithms, although it functions better with the flat algorithm in a small-scale agricultural network. PMID:22346622

  5. Developing a new wireless sensor network platform and its application in precision agriculture.

    PubMed

    Aquino-Santos, Raúl; González-Potes, Apolinar; Edwards-Block, Arthur; Virgen-Ortiz, Raúl Alejandro

    2011-01-01

    Wireless sensor networks are gaining greater attention from the research community and industrial professionals because these small pieces of "smart dust" offer great advantages due to their small size, low power consumption, easy integration and support for "green" applications. Green applications are considered a hot topic in intelligent environments, ubiquitous and pervasive computing. This work evaluates a new wireless sensor network platform and its application in precision agriculture, including its embedded operating system and its routing algorithm. To validate the technological platform and the embedded operating system, two different routing strategies were compared: hierarchical and flat. Both of these routing algorithms were tested in a small-scale network applied to a watermelon field. However, we strongly believe that this technological platform can be also applied to precision agriculture because it incorporates a modified version of LORA-CBF, a wireless location-based routing algorithm that uses cluster-based flooding. Cluster-based flooding addresses the scalability concerns of wireless sensor networks, while the modified LORA-CBF routing algorithm includes a metric to monitor residual battery energy. Furthermore, results show that the modified version of LORA-CBF functions well with both the flat and hierarchical algorithms, although it functions better with the flat algorithm in a small-scale agricultural network.

  6. Correction for Self-Heating When Using Thermometers as Heaters in Precision Control Applications

    NASA Technical Reports Server (NTRS)

    Ressler, Michael E.; Cho, Hyung J.; Sukhatme, Kalyani G.

    2011-01-01

    In precision control applications, thermometers have temperature-dependent electrical resistance with germanium or other semiconductor material thermistors, diodes, metal film and wire, or carbon film resistors. Because resistance readout requires excitation current flowing through the sensor, there is always ohmic heating that leads to a temperature difference between the sensing element and the monitored object. In this work, a thermistor can be operated as a thermometer and a heater, simultaneously, by continuously measuring the excitation current and the corresponding voltage. This work involves a method of temperature readout where the temperature offset due to self-heating is subtracted exactly.

  7. Development of high precision laser measurement to Space Debris and Applications in SHAO

    NASA Astrophysics Data System (ADS)

    Zhang, Zhongping; Chen, Juping; Xiong, Yaoheng; Han, Xingwei

    2016-07-01

    Artificial space debris has become the focus during the space exploration because of producing the damage for the future active spacecrafts and high precision measurement for space debris are required for debris surveillance and collision avoidance. Laser ranging technology is inherently high accurate and will play an important role in precise orbit determination, accurate catalog of space debris. Shanghai Astronomical Observatory (SHAO) of CAS, has been developing the technology of laser measurement to space debris for several years. According to characteristics of laser echoes from space debris and the experiences of relevant activities, high repetition rate, high power laser system and low dark noise APD detector with high quantum efficiency and high transmissivity of narrow bandwidth spectral filter are applied to laser measurement to space debris in SHAO. With these configurations, great achievements of laser measurement to space debris are made with hundreds of passes of laser data from space debris in the distance between 500km and 2500km with Radar Cross Section (RCS) of more than 10 m^{2} to less than 0.5m^{2} at the measuring precision of less than 1m (RMS). For better application of laser ranging technology, Chinese Space Debris Observation network, consisting of Shanghai, Changchun and Kunming station, has been preliminary developed and the coordinated observation has been performed to increase the measuring efficiency for space debris. It is referred from data that laser ranging technology can be as the essential high accuracy measurement technology in the study of space debris.

  8. [Role and management of cancer clinical database in the application of gastric cancer precision medicine].

    PubMed

    Li, Yuanfang; Zhou, Zhiwei

    2016-02-01

    Precision medicine is a new medical concept and medical model, which is based on personalized medicine, rapid progress of genome sequencing technology and cross application of biological information and big data science. Precision medicine improves the diagnosis and treatment of gastric cancer to provide more convenience through more profound analyses of characteristics, pathogenesis and other core issues in gastric cancer. Cancer clinical database is important to promote the development of precision medicine. Therefore, it is necessary to pay close attention to the construction and management of the database. The clinical database of Sun Yat-sen University Cancer Center is composed of medical record database, blood specimen bank, tissue bank and medical imaging database. In order to ensure the good quality of the database, the design and management of the database should follow the strict standard operation procedure(SOP) model. Data sharing is an important way to improve medical research in the era of medical big data. The construction and management of clinical database must also be strengthened and innovated.

  9. Application of machine-learning methods to solid-state chemistry: ferromagnetism in transition metal alloys

    NASA Astrophysics Data System (ADS)

    Landrum, Gregory A.; Genin, Hugh

    2003-12-01

    Machine-learning methods are a collection of techniques for building predictive models from experimental data. The algorithms are problem-independent: the chemistry and physics of the problem being studied are contained in the descriptors used to represent the known data. The application of a variety of machine-learning methods to the prediction of ferromagnetism in ordered and disordered transition metal alloys is presented. Applying a decision tree algorithm to build a predictive model for ordered phases results in a model that is 100% accurate. The same algorithm achieves 99% accuracy when trained on a data set containing both ordered and disordered phases. Details of the descriptor sets for both applications are also presented.

  10. Micromechanical Machining Processes and their Application to Aerospace Structures, Devices and Systems

    NASA Technical Reports Server (NTRS)

    Friedrich, Craig R.; Warrington, Robert O.

    1995-01-01

    Micromechanical machining processes are those micro fabrication techniques which directly remove work piece material by either a physical cutting tool or an energy process. These processes are direct and therefore they can help reduce the cost and time for prototype development of micro mechanical components and systems. This is especially true for aerospace applications where size and weight are critical, and reliability and the operating environment are an integral part of the design and development process. The micromechanical machining processes are rapidly being recognized as a complementary set of tools to traditional lithographic processes (such as LIGA) for the fabrication of micromechanical components. Worldwide efforts in the U.S., Germany, and Japan are leading to results which sometimes rival lithography at a fraction of the time and cost. Efforts to develop processes and systems specific to aerospace applications are well underway.

  11. Space applications of Automation, Robotics and Machine Intelligence Systems (ARAMIS). Volume 2: Space projects overview

    NASA Technical Reports Server (NTRS)

    Miller, R. H.; Minsky, M. L.; Smith, D. B. S.

    1982-01-01

    Applications of automation, robotics, and machine intelligence systems (ARAMIS) to space activities, and their related ground support functions are studied so that informed decisions can be made on which aspects of ARAMIS to develop. The space project breakdowns, which are used to identify tasks ('functional elements'), are described. The study method concentrates on the production of a matrix relating space project tasks to pieces of ARAMIS.

  12. Human facial neural activities and gesture recognition for machine-interfacing applications.

    PubMed

    Hamedi, M; Salleh, Sh-Hussain; Tan, T S; Ismail, K; Ali, J; Dee-Uam, C; Pavaganun, C; Yupapin, P P

    2011-01-01

    The authors present a new method of recognizing different human facial gestures through their neural activities and muscle movements, which can be used in machine-interfacing applications. Human-machine interface (HMI) technology utilizes human neural activities as input controllers for the machine. Recently, much work has been done on the specific application of facial electromyography (EMG)-based HMI, which have used limited and fixed numbers of facial gestures. In this work, a multipurpose interface is suggested that can support 2-11 control commands that can be applied to various HMI systems. The significance of this work is finding the most accurate facial gestures for any application with a maximum of eleven control commands. Eleven facial gesture EMGs are recorded from ten volunteers. Detected EMGs are passed through a band-pass filter and root mean square features are extracted. Various combinations of gestures with a different number of gestures in each group are made from the existing facial gestures. Finally, all combinations are trained and classified by a Fuzzy c-means classifier. In conclusion, combinations with the highest recognition accuracy in each group are chosen. An average accuracy >90% of chosen combinations proved their ability to be used as command controllers.

  13. Manipulating Crop Density to Optimize Nitrogen and Water Use: An Application of Precision Agroecology

    NASA Astrophysics Data System (ADS)

    Brown, T. T.; Huggins, D. R.; Smith, J. L.; Keller, C. K.; Kruger, C.

    2011-12-01

    Rising levels of reactive nitrogen (Nr) in the environment coupled with increasing population positions agriculture as a major contributor for supplying food and ecosystem services to the world. The concept of Precision Agroecology (PA) explicitly recognizes the importance of time and place by combining the principles of precision farming with ecology creating a framework that can lead to improvements in Nr use efficiency. In the Palouse region of the Pacific Northwest, USA, relationships between productivity, N dynamics and cycling, water availability, and environmental impacts result from intricate spatial and temporal variations in soil, ecosystem processes, and socioeconomic factors. Our research goal is to investigate N use efficiency (NUE) in the context of factors that regulate site-specific environmental and economic conditions and to develop the concept of PA for use in sustainable agroecosystems and science-based Nr policy. Nitrogen and plant density field trials with winter wheat (Triticum aestivum L.) were conducted at the Washington State University Cook Agronomy Farm near Pullman, WA under long-term no-tillage management in 2010 and 2011. Treatments were imposed across environmentally heterogeneous field conditions to assess soil, crop and environmental interactions. Microplots with a split N application using 15N-labeled fertilizer were established in 2011 to examine the impact of N timing on uptake of fertilizer and soil N throughout the growing season for two plant density treatments. Preliminary data show that plant density manipulation combined with precision N applications regulated water and N use and resulted in greater wheat yield with less seed and N inputs. These findings indicate that improvements to NUE and agroecosystem sustainability should consider landscape-scale patterns driving productivity (e.g., spatial and temporal dynamics of water availability and N transformations) and would benefit from policy incentives that promote a PA

  14. Estimated results analysis and application of the precise point positioning based high-accuracy ionosphere delay

    NASA Astrophysics Data System (ADS)

    Wang, Shi-tai; Peng, Jun-huan

    2015-12-01

    The characterization of ionosphere delay estimated with precise point positioning is analyzed in this paper. The estimation, interpolation and application of the ionosphere delay are studied based on the processing of 24-h data from 5 observation stations. The results show that the estimated ionosphere delay is affected by the hardware delay bias from receiver so that there is a difference between the estimated and interpolated results. The results also show that the RMSs (root mean squares) are bigger, while the STDs (standard deviations) are better than 0.11 m. When the satellite difference is used, the hardware delay bias can be canceled. The interpolated satellite-differenced ionosphere delay is better than 0.11 m. Although there is a difference between the between the estimated and interpolated ionosphere delay results it cannot affect its application in single-frequency positioning and the positioning accuracy can reach cm level.

  15. Improving accuracy and precision in biological applications of fluorescence lifetime imaging microscopy

    NASA Astrophysics Data System (ADS)

    Chang, Ching-Wei

    The quantitative understanding of cellular and molecular responses in living cells is important for many reasons, including identifying potential molecular targets for treatments of diseases like cancer. Fluorescence lifetime imaging microscopy (FLIM) can quantitatively measure these responses in living cells by producing spatially resolved images of fluorophore lifetime, and has advantages over intensity-based measurements. However, in live-cell microscopy applications using high-intensity light sources such as lasers, maintaining biological viability remains critical. Although high-speed, time-gated FLIM significantly reduces light delivered to live cells, making measurements at low light levels remains a challenge affecting quantitative FLIM results. We can significantly improve both accuracy and precision in gated FLIM applications. We use fluorescence resonance energy transfer (FRET) with fluorescent proteins to detect molecular interactions in living cells: the use of FLIM, better fluorophores, and temperature/CO2 controls can improve live-cell FRET results with higher consistency, better statistics, and less non-specific FRET (for negative control comparisons, p-value = 0.93 (physiological) vs. 9.43E-05 (non-physiological)). Several lifetime determination methods are investigated to optimize gating schemes. We demonstrate a reduction in relative standard deviation (RSD) from 52.57% to 18.93% with optimized gating in an example under typical experimental conditions. We develop two novel total variation (TV) image denoising algorithms, FWTV ( f-weighted TV) and UWTV (u-weighted TV), that can achieve significant improvements for real imaging systems. With live-cell images, they improve the precision of local lifetime determination without significantly altering the global mean lifetime values (<5% lifetime changes). Finally, by combining optimal gating and TV denoising, even low-light excitation can achieve precision better than that obtained in high

  16. On the applicability of brain reading for predictive human-machine interfaces in robotics.

    PubMed

    Kirchner, Elsa Andrea; Kim, Su Kyoung; Straube, Sirko; Seeland, Anett; Wöhrle, Hendrik; Krell, Mario Michael; Tabie, Marc; Fahle, Manfred

    2013-01-01

    The ability of today's robots to autonomously support humans in their daily activities is still limited. To improve this, predictive human-machine interfaces (HMIs) can be applied to better support future interaction between human and machine. To infer upcoming context-based behavior relevant brain states of the human have to be detected. This is achieved by brain reading (BR), a passive approach for single trial EEG analysis that makes use of supervised machine learning (ML) methods. In this work we propose that BR is able to detect concrete states of the interacting human. To support this, we show that BR detects patterns in the electroencephalogram (EEG) that can be related to event-related activity in the EEG like the P300, which are indicators of concrete states or brain processes like target recognition processes. Further, we improve the robustness and applicability of BR in application-oriented scenarios by identifying and combining most relevant training data for single trial classification and by applying classifier transfer. We show that training and testing, i.e., application of the classifier, can be carried out on different classes, if the samples of both classes miss a relevant pattern. Classifier transfer is important for the usage of BR in application scenarios, where only small amounts of training examples are available. Finally, we demonstrate a dual BR application in an experimental setup that requires similar behavior as performed during the teleoperation of a robotic arm. Here, target recognition processes and movement preparation processes are detected simultaneously. In summary, our findings contribute to the development of robust and stable predictive HMIs that enable the simultaneous support of different interaction behaviors.

  17. On the applicability of brain reading for predictive human-machine interfaces in robotics.

    PubMed

    Kirchner, Elsa Andrea; Kim, Su Kyoung; Straube, Sirko; Seeland, Anett; Wöhrle, Hendrik; Krell, Mario Michael; Tabie, Marc; Fahle, Manfred

    2013-01-01

    The ability of today's robots to autonomously support humans in their daily activities is still limited. To improve this, predictive human-machine interfaces (HMIs) can be applied to better support future interaction between human and machine. To infer upcoming context-based behavior relevant brain states of the human have to be detected. This is achieved by brain reading (BR), a passive approach for single trial EEG analysis that makes use of supervised machine learning (ML) methods. In this work we propose that BR is able to detect concrete states of the interacting human. To support this, we show that BR detects patterns in the electroencephalogram (EEG) that can be related to event-related activity in the EEG like the P300, which are indicators of concrete states or brain processes like target recognition processes. Further, we improve the robustness and applicability of BR in application-oriented scenarios by identifying and combining most relevant training data for single trial classification and by applying classifier transfer. We show that training and testing, i.e., application of the classifier, can be carried out on different classes, if the samples of both classes miss a relevant pattern. Classifier transfer is important for the usage of BR in application scenarios, where only small amounts of training examples are available. Finally, we demonstrate a dual BR application in an experimental setup that requires similar behavior as performed during the teleoperation of a robotic arm. Here, target recognition processes and movement preparation processes are detected simultaneously. In summary, our findings contribute to the development of robust and stable predictive HMIs that enable the simultaneous support of different interaction behaviors. PMID:24358125

  18. Rule extraction from support vector machines using ensemble learning approach: an application for diagnosis of diabetes.

    PubMed

    Han, Longfei; Luo, Senlin; Yu, Jianmin; Pan, Limin; Chen, Songjing

    2015-03-01

    Diabetes mellitus is a chronic disease and a worldwide public health challenge. It has been shown that 50-80% proportion of T2DM is undiagnosed. In this paper, support vector machines are utilized to screen diabetes, and an ensemble learning module is added, which turns the "black box" of SVM decisions into comprehensible and transparent rules, and it is also useful for solving imbalance problem. Results on China Health and Nutrition Survey data show that the proposed ensemble learning method generates rule sets with weighted average precision 94.2% and weighted average recall 93.9% for all classes. Furthermore, the hybrid system can provide a tool for diagnosis of diabetes, and it supports a second opinion for lay users.

  19. Lifelong personal health data and application software via virtual machines in the cloud.

    PubMed

    Van Gorp, Pieter; Comuzzi, Marco

    2014-01-01

    Personal Health Records (PHRs) should remain the lifelong property of patients, who should be able to show them conveniently and securely to selected caregivers and institutions. In this paper, we present MyPHRMachines, a cloud-based PHR system taking a radically new architectural solution to health record portability. In MyPHRMachines, health-related data and the application software to view and/or analyze it are separately deployed in the PHR system. After uploading their medical data to MyPHRMachines, patients can access them again from remote virtual machines that contain the right software to visualize and analyze them without any need for conversion. Patients can share their remote virtual machine session with selected caregivers, who will need only a Web browser to access the pre-loaded fragments of their lifelong PHR. We discuss a prototype of MyPHRMachines applied to two use cases, i.e., radiology image sharing and personalized medicine. PMID:24403402

  20. Complex extreme learning machine applications in terahertz pulsed signals feature sets.

    PubMed

    Yin, X-X; Hadjiloucas, S; Zhang, Y

    2014-11-01

    This paper presents a novel approach to the automatic classification of very large data sets composed of terahertz pulse transient signals, highlighting their potential use in biochemical, biomedical, pharmaceutical and security applications. Two different types of THz spectra are considered in the classification process. Firstly a binary classification study of poly-A and poly-C ribonucleic acid samples is performed. This is then contrasted with a difficult multi-class classification problem of spectra from six different powder samples that although have fairly indistinguishable features in the optical spectrum, they also possess a few discernable spectral features in the terahertz part of the spectrum. Classification is performed using a complex-valued extreme learning machine algorithm that takes into account features in both the amplitude as well as the phase of the recorded spectra. Classification speed and accuracy are contrasted with that achieved using a support vector machine classifier. The study systematically compares the classifier performance achieved after adopting different Gaussian kernels when separating amplitude and phase signatures. The two signatures are presented as feature vectors for both training and testing purposes. The study confirms the utility of complex-valued extreme learning machine algorithms for classification of the very large data sets generated with current terahertz imaging spectrometers. The classifier can take into consideration heterogeneous layers within an object as would be required within a tomographic setting and is sufficiently robust to detect patterns hidden inside noisy terahertz data sets. The proposed study opens up the opportunity for the establishment of complex-valued extreme learning machine algorithms as new chemometric tools that will assist the wider proliferation of terahertz sensing technology for chemical sensing, quality control, security screening and clinic diagnosis. Furthermore, the proposed

  1. Complex extreme learning machine applications in terahertz pulsed signals feature sets.

    PubMed

    Yin, X-X; Hadjiloucas, S; Zhang, Y

    2014-11-01

    This paper presents a novel approach to the automatic classification of very large data sets composed of terahertz pulse transient signals, highlighting their potential use in biochemical, biomedical, pharmaceutical and security applications. Two different types of THz spectra are considered in the classification process. Firstly a binary classification study of poly-A and poly-C ribonucleic acid samples is performed. This is then contrasted with a difficult multi-class classification problem of spectra from six different powder samples that although have fairly indistinguishable features in the optical spectrum, they also possess a few discernable spectral features in the terahertz part of the spectrum. Classification is performed using a complex-valued extreme learning machine algorithm that takes into account features in both the amplitude as well as the phase of the recorded spectra. Classification speed and accuracy are contrasted with that achieved using a support vector machine classifier. The study systematically compares the classifier performance achieved after adopting different Gaussian kernels when separating amplitude and phase signatures. The two signatures are presented as feature vectors for both training and testing purposes. The study confirms the utility of complex-valued extreme learning machine algorithms for classification of the very large data sets generated with current terahertz imaging spectrometers. The classifier can take into consideration heterogeneous layers within an object as would be required within a tomographic setting and is sufficiently robust to detect patterns hidden inside noisy terahertz data sets. The proposed study opens up the opportunity for the establishment of complex-valued extreme learning machine algorithms as new chemometric tools that will assist the wider proliferation of terahertz sensing technology for chemical sensing, quality control, security screening and clinic diagnosis. Furthermore, the proposed

  2. Micro-machining.

    PubMed

    Brinksmeier, Ekkard; Preuss, Werner

    2012-08-28

    Manipulating bulk material at the atomic level is considered to be the domain of physics, chemistry and nanotechnology. However, precision engineering, especially micro-machining, has become a powerful tool for controlling the surface properties and sub-surface integrity of the optical, electronic and mechanical functional parts in a regime where continuum mechanics is left behind and the quantum nature of matter comes into play. The surprising subtlety of micro-machining results from the extraordinary precision of tools, machines and controls expanding into the nanometre range-a hundred times more precise than the wavelength of light. In this paper, we will outline the development of precision engineering, highlight modern achievements of ultra-precision machining and discuss the necessity of a deeper physical understanding of micro-machining.

  3. High-precision gamma-ray spectroscopy for enhancing production and application of medical isotopes

    NASA Astrophysics Data System (ADS)

    McCutchan, E. A.; Sonzogni, A. A.; Smith, S. V.; Muench, L.; Nino, M.; Greene, J. P.; Carpenter, M. P.; Zhu, S.; Chillery, T.; Chowdhury, P.; Harding, R.; Lister, C. J.

    2015-10-01

    Nuclear medicine is a field which requires precise decay data for use in planning radionuclide production and in imaging and therapeutic applications. To address deficiencies in decay data, sources of medical isotopes were produced and purified at the Brookhaven Linear Isotope Producer (BLIP) then shipped to Argonne National Laboratory where high-precision, gamma-ray measurements were performed using Gammasphere. New decay schemes for a number of PET isotopes and the impact on dose calculations will be presented. To investigate the production of next-generation theranostic or radiotherapeutic isotopes, cross section measurements with high energy protons have also been explored at BLIP. The 100-200 MeV proton energy regime is relatively unexplored for isotope production, thus offering high discovery potential but at the same time a challenging analysis due to the large number of open channels at these energies. Results of cross sections deduced from Compton-suppressed, coincidence gamma-ray spectroscopy performed at Lowell will be presented, focusing on the production of platinum isotopes by irradiating natural platinum foils with 100 to 200 MeV protons. DOE Isotope Program is acknowledged for funding ST5001030. Work supported by the US DOE under Grant DE-FG02-94ER40848 and Contracts DE-AC02-98CH10946 and DE-AC02-06CH11357.

  4. Application of the spherical harmonic gravity model in high precision inertial navigation systems

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Yang, Gongliu; Li, Xiangyun; Zhou, Xiao

    2016-09-01

    The spherical harmonic gravity model (SHM) may, in general, be considered as a suitable alternative to the normal gravity model (NGM), because it represents the Earth’s gravitational field more accurately. However, the high-resolution SHM has never been used in current inertial navigation systems (INSs) due to its extremely complex expression. In this paper, the feasibility and accuracy of a truncated SHM are discussed for application in a real-time free-INS with a precision demand better than 0.8 nm h‑1. In particular, the time and space complexity are analyzed mathematically to verify the feasibility of the SHM. Also, a test on a typical navigation computer shows a storable range of cut-off degrees. To further evaluate the appropriate degree and accuracy of the truncated SHM, analyses of covariance and truncation error are proposed. Finally, a SHM of degree 12 is demonstrated to be the appropriate model for routine INSs in the precision range of 0.4–0.75 nm h‑1. Flight simulations and road tests show its outstanding performance over the traditional NGM.

  5. Study on individual stochastic model of GNSS observations for precise kinematic applications

    NASA Astrophysics Data System (ADS)

    Próchniewicz, Dominik; Szpunar, Ryszard

    2015-04-01

    The proper definition of mathematical positioning model, which is defined by functional and stochastic models, is a prerequisite to obtain the optimal estimation of unknown parameters. Especially important in this definition is realistic modelling of stochastic properties of observations, which are more receiver-dependent and time-varying than deterministic relationships. This is particularly true with respect to precise kinematic applications which are characterized by weakening model strength. In this case, incorrect or simplified definition of stochastic model causes that the performance of ambiguity resolution and accuracy of position estimation can be limited. In this study we investigate the methods of describing the measurement noise of GNSS observations and its impact to derive precise kinematic positioning model. In particular stochastic modelling of individual components of the variance-covariance matrix of observation noise performed using observations from a very short baseline and laboratory GNSS signal generator, is analyzed. Experimental test results indicate that the utilizing the individual stochastic model of observations including elevation dependency and cross-correlation instead of assumption that raw measurements are independent with the same variance improves the performance of ambiguity resolution as well as rover positioning accuracy. This shows that the proposed stochastic assessment method could be a important part in complex calibration procedure of GNSS equipment.

  6. Application of the spherical harmonic gravity model in high precision inertial navigation systems

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Yang, Gongliu; Li, Xiangyun; Zhou, Xiao

    2016-09-01

    The spherical harmonic gravity model (SHM) may, in general, be considered as a suitable alternative to the normal gravity model (NGM), because it represents the Earth’s gravitational field more accurately. However, the high-resolution SHM has never been used in current inertial navigation systems (INSs) due to its extremely complex expression. In this paper, the feasibility and accuracy of a truncated SHM are discussed for application in a real-time free-INS with a precision demand better than 0.8 nm h-1. In particular, the time and space complexity are analyzed mathematically to verify the feasibility of the SHM. Also, a test on a typical navigation computer shows a storable range of cut-off degrees. To further evaluate the appropriate degree and accuracy of the truncated SHM, analyses of covariance and truncation error are proposed. Finally, a SHM of degree 12 is demonstrated to be the appropriate model for routine INSs in the precision range of 0.4-0.75 nm h-1. Flight simulations and road tests show its outstanding performance over the traditional NGM.

  7. Design and control of a macro-micro robot for precise force applications

    NASA Technical Reports Server (NTRS)

    Wang, Yulun; Mangaser, Amante; Laby, Keith; Jordan, Steve; Wilson, Jeff

    1993-01-01

    Creating a robot which can delicately interact with its environment has been the goal of much research. Primarily two difficulties have made this goal hard to attain. The execution of control strategies which enable precise force manipulations are difficult to implement in real time because such algorithms have been too computationally complex for available controllers. Also, a robot mechanism which can quickly and precisely execute a force command is difficult to design. Actuation joints must be sufficiently stiff, frictionless, and lightweight so that desired torques can be accurately applied. This paper describes a robotic system which is capable of delicate manipulations. A modular high-performance multiprocessor control system was designed to provide sufficient compute power for executing advanced control methods. An 8 degree of freedom macro-micro mechanism was constructed to enable accurate tip forces. Control algorithms based on the impedance control method were derived, coded, and load balanced for maximum execution speed on the multiprocessor system. Delicate force tasks such as polishing, finishing, cleaning, and deburring, are the target applications of the robot.

  8. Extended precision data types for the development of the original computer aided engineering applications

    NASA Astrophysics Data System (ADS)

    Pescaru, A.; Oanta, E.; Axinte, T.; Dascalescu, A.-D.

    2015-11-01

    Computer aided engineering is based on models of the phenomena which are expressed as algorithms. The implementations of the algorithms are usually software applications which are processing a large volume of numerical data, regardless the size of the input data. In this way, the finite element method applications used to have an input data generator which was creating the entire volume of geometrical data, starting from the initial geometrical information and the parameters stored in the input data file. Moreover, there were several data processing stages, such as: renumbering of the nodes meant to minimize the size of the band length of the system of equations to be solved, computation of the equivalent nodal forces, computation of the element stiffness matrix, assemblation of system of equations, solving the system of equations, computation of the secondary variables. The modern software application use pre-processing and post-processing programs to easily handle the information. Beside this example, CAE applications use various stages of complex computation, being very interesting the accuracy of the final results. Along time, the development of CAE applications was a constant concern of the authors and the accuracy of the results was a very important target. The paper presents the various computing techniques which were imagined and implemented in the resulting applications: finite element method programs, finite difference element method programs, applied general numerical methods applications, data generators, graphical applications, experimental data reduction programs. In this context, the use of the extended precision data types was one of the solutions, the limitations being imposed by the size of the memory which may be allocated. To avoid the memory-related problems the data was stored in files. To minimize the execution time, part of the file was accessed using the dynamic memory allocation facilities. One of the most important consequences of the

  9. Application of deadbeat control with constraint and non-ripple in precision rapid displacement system

    NASA Astrophysics Data System (ADS)

    Li, Peng; Cui, Jiwen; Tan, Jiubin; Ding, Xuemei

    2015-02-01

    In order to enable the output response of a precision rapid displacement system to rapidly track the input instructions, and solve the problem of excessive control amplitude in the shortest period of time, deadbeat control with constraint and non-ripple can be used to enhance the system response rate under the constraint. Simulation results show that the steady-state step signal tracking error of a system can reach +/-1.5μm under random disturbance, and the step response is rapid and accurate. Compared with general control strategies, this method has a digital control design to increase the speed of response, the fine anti-disturbance ability, and the potential for wide application.

  10. TRB3: a 264 channel high precision TDC platform and its applications

    NASA Astrophysics Data System (ADS)

    Neiser, A.; Adamczewski-Musch, J.; Hoek, M.; Koenig, W.; Korcyl, G.; Linev, S.; Maier, L.; Michel, J.; Palka, M.; Penschuck, M.; Traxler, M.; Uğur, C.; Zink, A.

    2013-12-01

    The TRB3 features four FPGA-based TDCs with < 20 ps RMS time precision between two channels and 256+4+4 channels in total. One central FPGA provides flexible trigger functionality and GbE connectivity including powerful slow control. We present recent users' applications of this platform following the COME&KISS principle: successful test beamtimes at CERN (CBM), in Jülich and Mainz with an FPGA-based discriminator board (PaDiWa), a charge-to-width FEE board with high dynamic range, read-out of the n-XYTER ASIC and software for data unpacking and TDC calibration in ROOT. We conclude with an outlook on future developments.

  11. Precision neutron flux measurements and applications using the Alpha Gamma device

    NASA Astrophysics Data System (ADS)

    Anderson, Eamon; Alpha Gamma; BL2 Collaboration

    2015-04-01

    The Alpha Gamma device is a totally-absorbing 10 B neutron detector designed to measure the absolute detection efficiency of a thin-film lithium neutron monitor on a monoenergetic neutron beam. The detector has been shown to measure neutron fluence with an absolute accuracy of 0.06%. This capability has been used to perform the first direct, absolute measurement of the 6Li(n , t) 4He cross section at sub-thermal energy, improve the neutron fluence determination in a past beam neutron lifetime measurement by a factor of five, and is being used to calibrate the neutron monitors for use in the upcoming beam neutron lifetime measurement BL2 (NIST Beam Lifetime 2). The principle of the measurement method will presented and the applications will be discussed. We would like to acknowledge support of this research through the NSF-PHY-1068712 grant as well as the NIST Precision Measurement Grant program.

  12. Precision neutron flux measurements and applications using the Alpha Gamma device

    NASA Astrophysics Data System (ADS)

    Anderson, Eamon

    2016-03-01

    The Alpha Gamma device is a totally-absorbing 10 B neutron detector designed to measure the absolute detection efficiency of a thin-film lithium neutron monitor on a monoenergetic neutron beam. The detector has been shown to measure neutron fluence with an absolute accuracy of 0.06%. This capability has been used to perform the first direct, absolute measurement of the 6Li(n,t) 4He cross section at sub-thermal energy, improve the neutron fluence determination in a past beam neutron lifetime measurement by a factor of five, and is being used to calibrate the neutron monitors for use in the upcoming beam neutron lifetime measurement BL2 (NIST Beam Lifetime 2). The principle of the measurement method will presented and the applications will be discussed. We would like to acknowledge support of this research through the NSF-PHY-1068712 Grant as well as the NIST Precision Measurement Grant program.

  13. High-precision control of LSRM based X-Y table for industrial applications.

    PubMed

    Pan, J F; Cheung, Norbert C; Zou, Yu

    2013-01-01

    The design of an X-Y table applying direct-drive linear switched reluctance motor (LSRM) principle is proposed in this paper. The proposed X-Y table has the characteristics of low cost, simple and stable mechanical structure. After the design procedure is introduced, an adaptive position control method based on online parameter identification and pole-placement regulation scheme is developed for the X-Y table. Experimental results prove the feasibility and its priority over a traditional PID controller with better dynamic response, static performance and robustness to disturbances. It is expected that the novel two-dimensional direct-drive system find its applications in high-precision manufacture area.

  14. Application of hot-pressed silicon carbide to large high-precision optical structures

    NASA Astrophysics Data System (ADS)

    Shih, C. James; Ezis, Andris

    1995-10-01

    A new grade of silicon carbide has been developed with properties that make it very attractive for a variety of applications in precision optical structures. Its microstructural homogeneity makes it capable of accepting an optical finish with subnanometer surface roughness. Its strength and fracture toughness, on a bulk scale, exceed all previous silicon carbide materials. This hot-pressed silicon carbide can be produced in single blocks up to 50 cm square and up to 20 cm thick. Two bonding techniques have been developed for fusing large segments of hot pressed silicon carbide together into a large monolith for constructing large optical structures without using a metallic braze. Bonding structure and bonding strength are discussed.

  15. Six-Port Based Interferometry for Precise Radar and Sensing Applications.

    PubMed

    Koelpin, Alexander; Lurz, Fabian; Linz, Sarah; Mann, Sebastian; Will, Christoph; Lindner, Stefan

    2016-09-22

    Microwave technology plays a more important role in modern industrial sensing applications. Pushed by the significant progress in monolithic microwave integrated circuit technology over the past decades, complex sensing systems operating in the microwave and even millimeter-wave range are available for reasonable costs combined with exquisite performance. In the context of industrial sensing, this stimulates new approaches for metrology based on microwave technology. An old measurement principle nearly forgotten over the years has recently gained more and more attention in both academia and industry: the six-port interferometer. This paper reviews the basic concept, investigates promising applications in remote, as well as contact-based sensing and compares the system with state-of-the-art metrology. The significant advantages will be discussed just as the limitations of the six-port architecture. Particular attention will be paid to impairment effects and non-ideal behavior, as well as compensation and linearization concepts. It will be shown that in application fields, like remote distance sensing, precise alignment measurements, as well as interferometrically-evaluated mechanical strain analysis, the six-port architecture delivers extraordinary measurement results combined with high measurement data update rates for reasonable system costs. This makes the six-port architecture a promising candidate for industrial metrology.

  16. Six-Port Based Interferometry for Precise Radar and Sensing Applications.

    PubMed

    Koelpin, Alexander; Lurz, Fabian; Linz, Sarah; Mann, Sebastian; Will, Christoph; Lindner, Stefan

    2016-01-01

    Microwave technology plays a more important role in modern industrial sensing applications. Pushed by the significant progress in monolithic microwave integrated circuit technology over the past decades, complex sensing systems operating in the microwave and even millimeter-wave range are available for reasonable costs combined with exquisite performance. In the context of industrial sensing, this stimulates new approaches for metrology based on microwave technology. An old measurement principle nearly forgotten over the years has recently gained more and more attention in both academia and industry: the six-port interferometer. This paper reviews the basic concept, investigates promising applications in remote, as well as contact-based sensing and compares the system with state-of-the-art metrology. The significant advantages will be discussed just as the limitations of the six-port architecture. Particular attention will be paid to impairment effects and non-ideal behavior, as well as compensation and linearization concepts. It will be shown that in application fields, like remote distance sensing, precise alignment measurements, as well as interferometrically-evaluated mechanical strain analysis, the six-port architecture delivers extraordinary measurement results combined with high measurement data update rates for reasonable system costs. This makes the six-port architecture a promising candidate for industrial metrology. PMID:27669246

  17. Precise Directed Assembly of Nanoparticles for Electronic, Optical and Biomedical Applications

    NASA Astrophysics Data System (ADS)

    Yilmaz, Cihan

    Assembly of nano building blocks offers a versatile route to the creation of complex 1, 2 and 3-dimensional homogenous or hybrid nanostructures with unique properties to be used in many applications including electronics, optics, energy, and biotechnology. Bottom-up directed assembly of nanoparticles has been recently considered as one of the best approaches to manufacture such functional and novel nanostructures. However, current directed assembly techniques have not been shown to make nanostructures homogeneous or hybrid materials with nanoscale precision at a high yield. This is mainly due to the lack of fundamental understanding of the forces driving the assembly of nanoparticles into organized nanostructures on surfaces and the difficulties in precisely controlling these forces to enable the repeatable and reliable assembly of various types of organic or inorganic nanoparticles. We experimentally and numerically investigated the fundamental mechanism of the electrophoretic directed assembly for different sizes and types of nanoparticles. The results showed that unlike large (such as 500nm) Polysterene Latex (PSL) particles, the electrophoretic assembly of 50nm and smaller PSL particles is significantly influenced by the Brownian diffusion. This results in random and low yield assembly for the smaller nanoparticles. In order to overcome the Brownian diffusion-limited assembly of 50nm or smaller particles, the electrophoretic velocity of the particles must be increased. This can be accomplished by increasing the electrophoretic force, which is a function of particle surface charge and applied voltage. The surface charge of the PSL particles is greatly influenced by the pH of the solution. At high pH values (pH 10.1 or above), the nanoparticles attain higher charge, which increases the electrophoretic force. Consequently, the Brownian diffusion can also be overcome by increasing the pH of the solution. Overcoming the Brownian motion at low pH values (<10

  18. A review on nozzle wear in abrasive water jet machining application

    NASA Astrophysics Data System (ADS)

    Syazwani, H.; Mebrahitom, G.; Azmir, A.

    2016-02-01

    This paper discusses a review on nozzle wear in abrasive water jet machining application. Wear of the nozzle becomes a major problem since it may affect the water jet machining performance. Design, materials, and life of the nozzle give significance effect to the nozzle wear. There are various parameters that may influence the wear rate of the nozzle such as nozzle length, nozzle inlet angle, nozzle diameter, orifice diameter, abrasive flow rate and water pressure. The wear rate of the nozzle can be minimized by controlling these parameters. The mechanism of wear in the nozzle is similar to other traditional machining processes which uses a cutting tool. The high pressure of the water and hard abrasive particles may erode the nozzle wall. A new nozzle using a tungsten carbide-based material has been developed to reduce the wear rate and improve the nozzle life. Apart from that, prevention of the nozzle wear has been achieved using porous lubricated nozzle. This paper presents a comprehensive review about the wear of abrasive water jet nozzle.

  19. Contributions to the study of ultrasonic machining. [characteristics of ultrasonic sound generators for industrial applications

    NASA Technical Reports Server (NTRS)

    Savii, G.; Iclanzan, T.

    1974-01-01

    Problems in the industrial application of ultrasounds are discussed. Starting from the industrial characteristics of ultrasonic working, especially of hard and fragile materials that are difficult to work by means of conventional methods, the characteristics of the feed system, the circulation system of the abrasive suspension, and the ultra-acoustic unit of machines for ultrasonic working are described. Experiments on the behavior of different types of ultra-acoustic unit design and on the optimal operating conditions connected with the manner of execution, fixation, and excitation conditions are analyzed.

  20. Polygon Scanner System for Ultra Short Pulsed Laser Micro-Machining Applications

    NASA Astrophysics Data System (ADS)

    De Loor, R.

    Ultra short pulsed lasers have gained acceptance in micro-machining applications and many processes have been developed in the lab. Transferring the technology to the manufacturing floor started few years ago as soon as relatively high average power (> 5W) lasers became available. Now that high repetition rates and average powers of 50 Watt and more are reaching the market, the commercially available galvo based laser scanners systems limit the efficient use of this expensive laser power. We present a novel polygon based scanner system incorporating laser and scanner synchronization enabling writing speeds of 50 m/sec and higher.

  1. Application of neural adaptive power system stabilizer in a multi-machine power system

    SciTech Connect

    Shamsollahi, P.; Malik, O.P.

    1999-09-01

    Application of a neural adaptive power system stabilizer (NAPSS) to a five-machine power system is described in this paper. The proposed NAPSS comprises two subnetworks. The adaptive neuro-identifier (ANI) to dynamically identify the non-linear plant, and the adaptive neuro-controller (ANC) to damp output oscillations. The back-propagation training method is used on-line to train these subnetworks. The effectiveness of the proposed NAPSS in damping both local and inter-area modes of oscillations and its self-coordination ability are demonstrated.

  2. Application of machine learning techniques to analyse the effects of physical exercise in ventricular fibrillation.

    PubMed

    Caravaca, Juan; Soria-Olivas, Emilio; Bataller, Manuel; Serrano, Antonio J; Such-Miquel, Luis; Vila-Francés, Joan; Guerrero, Juan F

    2014-02-01

    This work presents the application of machine learning techniques to analyse the influence of physical exercise in the physiological properties of the heart, during ventricular fibrillation. To this end, different kinds of classifiers (linear and neural models) are used to classify between trained and sedentary rabbit hearts. The use of those classifiers in combination with a wrapper feature selection algorithm allows to extract knowledge about the most relevant features in the problem. The obtained results show that neural models outperform linear classifiers (better performance indices and a better dimensionality reduction). The most relevant features to describe the benefits of physical exercise are those related to myocardial heterogeneity, mean activation rate and activation complexity.

  3. Potential application of machine vision technology to saffron (Crocus sativus L.) quality characterization.

    PubMed

    Kiani, Sajad; Minaei, Saeid

    2016-12-01

    Saffron quality characterization is an important issue in the food industry and of interest to the consumers. This paper proposes an expert system based on the application of machine vision technology for characterization of saffron and shows how it can be employed in practical usage. There is a correlation between saffron color and its geographic location of production and some chemical attributes which could be properly used for characterization of saffron quality and freshness. This may be accomplished by employing image processing techniques coupled with multivariate data analysis for quantification of saffron properties. Expert algorithms can be made available for prediction of saffron characteristics such as color as well as for product classification.

  4. Precise evaluation of GNSS position and latency errors in dynamic agricultural applications

    NASA Astrophysics Data System (ADS)

    Sama, Michael Patrick

    A method for precisely synchronizing an external serial data stream to the pulseper- second (PPS) output signal from a global navigation satellite-based system (GNSS) receiver was investigated. A signal timing device was designed that used a digital signal processor (DSP) with serial inputs and input captures to generate time stamps for asynchronous serial data based on an 58593.75 Hz internal timer. All temporal measurements were made directly in hardware to eliminate software latency. The resolution of the system was 17.1 is, which translated to less than one millimeter of horizontal position error at travel speeds typical of most agricultural operations. The dynamic error of a TTS was determined using a rotary test fixture. Tests were performed at angular velocities ranging from 0 to 3.72 rad/s and a radius of 0.635 m. Average latency from the TTS was shown to be consistently near 0.252 s for all angular velocities and less variable when using a reflector based machine target versus a prism target. Sight distance from the target to the TTS was shown to have very little effect on accuracy between 4 and 30 m. The TTS was determined to be a limited as a position reference for dynamic GNSS and vehicle auto-guidance testing based on angular velocity. The dynamic error of a GNSS receiver was determined using the rotary test fixture and modeled as discrete probability density functions for varying angular velocities and filter levels. GNSS position and fixture data were recorded for angular velocities of 0.824, 1.423, 2.018, 2.618, and 3.222 rad/s at a 1 m radius. Filter levels were adjusted to four available settings including; no filter, normal filter, high filter, and max filter. Each data set contained 4 hours of continuous operation and was replicated three times. Results showed that higher angular velocities increased the variability of the distribution of error while not having a significant effect on average error. The distribution of error tended to change

  5. Ultrahigh-precision GPS applications using real-time kinematic technology

    NASA Astrophysics Data System (ADS)

    Kim, D.; Langley, R. B.

    2003-04-01

    RTK (real-time kinematic) processing is a GPS technique pioneered by surveyors and geodesists for determining the coordinates of points with centimetre-level accuracy or better in "real-time". GPS carrier-phase measurements must be used to attain the required positioning accuracies. As improvements are made in positioning accuracies which can be achieved in real-time, RTK techniques are being embraced for an increasing number of applications so that the distinction between navigation and geodesy applications is becoming less distinct. This is evident in high-precision, real-time, scientific and civil applications such as establishing geodetic control networks, mitigating earthquake hazards, monitoring dam and bridge deformation, auto-steering gantry cranes and so on. These applications require positioning accuracies better than a few centimetres with extremely high reliability in either static or kinematic mode and in both post-processing and real-time situations. The University of New Brunswick (UNB) RTK software, initially designed for a gantry crane auto-steering system at Korea International Terminals' Kwangyang Port in South Korea, is able to provide navigation solutions in real time at an up to 25 Hz update rate commensurate with the dual-frequency data rate. The software works in conjunction with a GPS receiver and 2.4 GHz wireless LAN (WLAN) master unit at a base station and two dual-frequency GPS receivers and a WLAN adapter installed on the cranes. We have explored the capabilities of the software in new GPS applications. Recently, tests of this software for deformation monitoring have been carried out at Highland Valley Copper Mine in British Columbia, Canada. Also, tests to investigate the performance of the software under long-baseline situations including on-land and offshore environments are planned. UHF point-to-point, WLAN and LAN communications will be used for real-time testing. In this contribution, we introduce the UNB RTK approach. Technical

  6. Amelioration de la precision d'un bras robotise pour une application d'ebavurage

    NASA Astrophysics Data System (ADS)

    Mailhot, David

    Process automation is a more and more referred solution when it comes to complex, tedious or even dangerous tasks for human. Flexibility, low cost and compactness make industrial robots very attractive for automation. Even if many developments have been made to enhance robot's performances, they still can not meet some industries requirements. For instance, aerospace industry requires very tight tolerances on a large variety of parts, which is not what robots were designed for at first. When it comes to robotic deburring, robot imprecision is a major problem that needs to be addressed before it can be implemented in production. This master's thesis explores different calibration techniques for robot's dimensions that could overcome the problem and make the robotic deburring application possible. Some calibration techniques that are easy to implement in production environment are simulated and compared. A calibration technique for tool's dimensions is simulated and implemented to evaluate its potential. The most efficient technique will be used within the application. Finally, the production environment and requirements are explained. The remaining imprecision will be compensated by the use of a force/torque sensor integrated with the robot's controller and by the use of a camera. Many tests are made to define the best parameters to use to deburr a specific feature on a chosen part. Concluding tests are shown and demonstrate the potential use of robotic deburring. Keywords: robotic calibration, robotic arm, robotic precision, robotic deburring

  7. Precise time dissemination and applications development on the Bonneville Power Administration system

    NASA Technical Reports Server (NTRS)

    Martin, Ken E.; Esztergalyos, J.

    1992-01-01

    The Bonneville Power Administration (BPA) uses IRIG-B transmitted over microwave as its primary system time dissemination. Problems with accuracy and reliability have led to ongoing research into better methods. BPA has also developed and deployed a unique fault locator which uses precise clocks synchronized by a pulse over microwaves. It automatically transmits the data to a central computer for analysis. A proposed system could combine fault location timing and time dissemination into a Global Position System (GPS) timing receiver and close the verification loop through a master station at the Dittmer Control Center. Such a system would have many advantages, including lower cost, higher reliability, and wider industry support. Test results indicate the GPS has sufficient accuracy and reliability for this and other current timing requirements including synchronous phase angle measurements. A phasor measurement system which provides phase angle has recently been tested with excellent results. Phase angle is a key parameter in power system control applications including dynamic braking, DC modulation, remedial action schemes, and system state estimation. Further research is required to determine the applications which can most effectively use real-time phase angle measurements and the best method to apply them.

  8. A fast algorithm to compute precise type-2 centroids for real-time control applications.

    PubMed

    Chakraborty, Sumantra; Konar, Amit; Ralescu, Anca; Pal, Nikhil R

    2015-02-01

    An interval type-2 fuzzy set (IT2 FS) is characterized by its upper and lower membership functions containing all possible embedded fuzzy sets, which together is referred to as the footprint of uncertainty (FOU). The FOU results in a span of uncertainty measured in the defuzzified space and is determined by the positional difference of the centroids of all the embedded fuzzy sets taken together. This paper provides a closed-form formula to evaluate the span of uncertainty of an IT2 FS. The closed-form formula offers a precise measurement of the degree of uncertainty in an IT2 FS with a runtime complexity less than that of the classical iterative Karnik-Mendel algorithm and other formulations employing the iterative Newton-Raphson algorithm. This paper also demonstrates a real-time control application using the proposed closed-form formula of centroids with reduced root mean square error and computational overhead than those of the existing methods. Computer simulations for this real-time control application indicate that parallel realization of the IT2 defuzzification outperforms its competitors with respect to maximum overshoot even at high sampling rates. Furthermore, in the presence of measurement noise in system (plant) states, the proposed IT2 FS based scheme outperforms its type-1 counterpart with respect to peak overshoot and root mean square error in plant response.

  9. Prompt and Precise Prototyping

    NASA Technical Reports Server (NTRS)

    2003-01-01

    For Sanders Design International, Inc., of Wilton, New Hampshire, every passing second between the concept and realization of a product is essential to succeed in the rapid prototyping industry where amongst heavy competition, faster time-to-market means more business. To separate itself from its rivals, Sanders Design aligned with NASA's Marshall Space Flight Center to develop what it considers to be the most accurate rapid prototyping machine for fabrication of extremely precise tooling prototypes. The company's Rapid ToolMaker System has revolutionized production of high quality, small-to-medium sized prototype patterns and tooling molds with an exactness that surpasses that of computer numerically-controlled (CNC) machining devices. Created with funding and support from Marshall under a Small Business Innovation Research (SBIR) contract, the Rapid ToolMaker is a dual-use technology with applications in both commercial and military aerospace fields. The advanced technology provides cost savings in the design and manufacturing of automotive, electronic, and medical parts, as well as in other areas of consumer interest, such as jewelry and toys. For aerospace applications, the Rapid ToolMaker enables fabrication of high-quality turbine and compressor blades for jet engines on unmanned air vehicles, aircraft, and missiles.

  10. Monel Machining

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Castle Industries, Inc. is a small machine shop manufacturing replacement plumbing repair parts, such as faucet, tub and ballcock seats. Therese Castley, president of Castle decided to introduce Monel because it offered a chance to improve competitiveness and expand the product line. Before expanding, Castley sought NERAC assistance on Monel technology. NERAC (New England Research Application Center) provided an information package which proved very helpful. The NASA database was included in NERAC's search and yielded a wealth of information on machining Monel.

  11. Applications of color machine vision in the agricultural and food industries

    NASA Astrophysics Data System (ADS)

    Zhang, Min; Ludas, Laszlo I.; Morgan, Mark T.; Krutz, Gary W.; Precetti, Cyrille J.

    1999-01-01

    Color is an important factor in Agricultural and the Food Industry. Agricultural or prepared food products are often grade by producers and consumers using color parameters. Color is used to estimate maturity, sort produce for defects, but also perform genetic screenings or make an aesthetic judgement. The task of sorting produce following a color scale is very complex, requires special illumination and training. Also, this task cannot be performed for long durations without fatigue and loss of accuracy. This paper describes a machine vision system designed to perform color classification in real-time. Applications for sorting a variety of agricultural products are included: e.g. seeds, meat, baked goods, plant and wood.FIrst the theory of color classification of agricultural and biological materials is introduced. Then, some tools for classifier development are presented. Finally, the implementation of the algorithm on real-time image processing hardware and example applications for industry is described. This paper also presented an image analysis algorithm and a prototype machine vision system which was developed for industry. This system will automatically locate the surface of some plants using digital camera and predict information such as size, potential value and type of this plant. The algorithm developed will be feasible for real-time identification in an industrial environment.

  12. Military and Government Applications of Human-Machine Communication by Voice

    NASA Astrophysics Data System (ADS)

    Weinstein, Clifford J.

    1995-10-01

    This paper describes a range of opportunities for military and government applications of human-machine communication by voice, based on visits and contacts with numerous user organizations in the United States. The applications include some that appear to be feasible by careful integration of current state-of-the-art technology and others that will require a varying mix of advances in speech technology and in integration of the technology into applications environments. Applications that are described include (1) speech recognition and synthesis for mobile command and control; (2) speech processing for a portable multifunction soldier's computer; (3) speech- and language-based technology for naval combat team tactical training; (4) speech technology for command and control on a carrier flight deck; (5) control of auxiliary systems, and alert and warning generation, in fighter aircraft and helicopters; and (6) voice check-in, report entry, and communication for law enforcement agents or special forces. A phased approach for transfer of the technology into applications is advocated, where integration of applications systems is pursued in parallel with advanced research to meet future needs.

  13. Application de la methode de la reponse frequentielle a l'arret "SSFR", sur une machine synchrone a poles saillants de grande puissance

    NASA Astrophysics Data System (ADS)

    Belqorchi, Abdelghafour

    Forty years after Watson and Manchur conducted the Stand-Still Frequency Response (SSFR) test on a large turbogenerator, the applicability of this technic on a powerful salient pole synchronous generator has yet to be confirmed. The scientific literature on the subject is rare and very few have attempted to compare SSFR parameter results with those deduced by classical tests. The validity of SSFR on large salient pole machines has still to be proven. The present work aims in participating to fill this knowledge gap. It can be used to build a database of measurements highly needed to draw the validity of the technic. Also, the author hopes to demonstrate the potential of SSFR model to represent the machine, not only in cases of weak disturbances but also strong ones such as instantaneous three-phase short-circuit faults. The difficulties raised by previous searchers are: The lack of accuracy in very low frequency measurements; The difficulty in rotor positioning, according to d and q axes, in case of salient pole machines; The measurement current level influence on magnetizing inductances, in axes-d and; The rotation impact on damper circuits for some rotors design. Aware of the above difficulties, the author conducted an SSFR test on a large salient pole machine (285 MVA). The generator under test has laminated non isolated rotor and an integral slot number. The damper windings in adjacent poles are connected together, via the polar core and the rotor rim. Finally, the damping circuit is unaffected by rotation. To improve the measurement accuracy, in very low frequencies, the most precise frequency response analyser available on the market was used. Besides, the frequency responses of the signals conditioning modules (i.e., isolation, amplification...) were accounted for to correct the four measured SSFR transfer functions. Immunization against noise and use of instrumentation in their optimum range, were other technics rigorously applied. Magnetizing inductances

  14. Uav Multispectral Survey to Map Soil and Crop for Precision Farming Applications

    NASA Astrophysics Data System (ADS)

    Sonaa, Giovanna; Passoni, Daniele; Pinto, Livio; Pagliari, Diana; Masseroni, Daniele; Ortuani, Bianca; Facchi, Arianna

    2016-06-01

    New sensors mounted on UAV and optimal procedures for survey, data acquisition and analysis are continuously developed and tested for applications in precision farming. Procedures to integrate multispectral aerial data about soil and crop and ground-based proximal geophysical data are a recent research topic aimed to delineate homogeneous zones for the management of agricultural inputs (i.e., water, nutrients). Multispectral and multitemporal orthomosaics were produced over a test field (a 100 m x 200 m plot within a maize field), to map vegetation and soil indices, as well as crop heights, with suitable ground resolution. UAV flights were performed in two moments during the crop season, before sowing on bare soil, and just before flowering when maize was nearly at the maximum height. Two cameras, for color (RGB) and false color (NIR-RG) images, were used. The images were processed in Agisoft Photoscan to produce Digital Surface Model (DSM) of bare soil and crop, and multispectral orthophotos. To overcome some difficulties in the automatic searching of matching points for the block adjustment of the crop image, also the scientific software developed by Politecnico of Milan was used to enhance images orientation. Surveys and image processing are described, as well as results about classification of multispectral-multitemporal orthophotos and soil indices.

  15. Structural Analysis and Testing of an Erectable Truss for Precision Segmented Reflector Application

    NASA Technical Reports Server (NTRS)

    Collins, Timothy J.; Fichter, W. B.; Adams, Richard R.; Javeed, Mehzad

    1995-01-01

    This paper describes analysis and test results obtained at Langley Research Center (LaRC) on a doubly curved testbed support truss for precision reflector applications. Descriptions of test procedures and experimental results that expand upon previous investigations are presented. A brief description of the truss is given, and finite-element-analysis models are described. Static-load and vibration test procedures are discussed, and experimental results are shown to be repeatable and in generally good agreement with linear finite-element predictions. Truss structural performance (as determined by static deflection and vibration testing) is shown to be predictable and very close to linear. Vibration test results presented herein confirm that an anomalous mode observed during initial testing was due to the flexibility of the truss support system. Photogrammetric surveys with two 131-in. reference scales show that the root-mean-square (rms) truss-surface accuracy is about 0.0025 in. Photogrammetric measurements also indicate that the truss coefficient of thermal expansion (CTE) is in good agreement with that predicted by analysis. A detailed description of the photogrammetric procedures is included as an appendix.

  16. Remote sensing with simulated unmanned aircraft imagery for precision agriculture applications

    USGS Publications Warehouse

    Hunt, E. Raymond; Daughtry, Craig S.T.; Mirsky, Steven B.; Hively, W. Dean

    2014-01-01

    An important application of unmanned aircraft systems (UAS) may be remote-sensing for precision agriculture, because of its ability to acquire images with very small pixel sizes from low altitude flights. The objective of this study was to compare information obtained from two different pixel sizes, one about a meter (the size of a small vegetation plot) and one about a millimeter. Cereal rye (Secale cereale) was planted at the Beltsville Agricultural Research Center for a winter cover crop with fall and spring fertilizer applications, which produced differences in biomass and leaf chlorophyll content. UAS imagery was simulated by placing a Fuji IS-Pro UVIR digital camera at 3-m height looking nadir. An external UV-IR cut filter was used to acquire true-color images; an external red cut filter was used to obtain color-infrared-like images with bands at near-infrared, green, and blue wavelengths. Plot-scale Green Normalized Difference Vegetation Index was correlated with dry aboveground biomass ( ${mbi {r}} = 0.58$ ), whereas the Triangular Greenness Index (TGI) was not correlated with chlorophyll content. We used the SamplePoint program to select 100 pixels systematically; we visually identified the cover type and acquired the digital numbers. The number of rye pixels in each image was better correlated with biomass ( ${mbi {r}} = 0.73$ ), and the average TGI from only leaf pixels was negatively correlated with chlorophyll content ( ${mbi {r}} = -0.72$ ). Thus, better information for crop requirements may be obtained using very small pixel sizes, but new algorithms based on computer vision are needed for analysis. It may not be necessary to geospatially register large numbers of photographs with very small pixel sizes. Instead, images could be analyzed as single plots along field transects.

  17. Autoresonant control of nonlinear mode in ultrasonic transducer for machining applications.

    PubMed

    Babitsky, V I; Astashev, V K; Kalashnikov, A N

    2004-04-01

    Experiments conducted in several countries have shown that the improvement of machining quality can be promoted through conversion of the cutting process into one involving controllable high-frequency vibration at the cutting zone. This is achieved through the generation and maintenance of ultrasonic vibration of the cutting tool to alter the fracture process of work-piece material cutting to one in which loading of the materials at the tool tip is incremental, repetitive and controlled. It was shown that excitation of the high-frequency vibro-impact mode of the tool-workpiece interaction is the most effective way of ultrasonic influence on the dynamic characteristics of machining. The exploitation of this nonlinear mode needs a new method of adaptive control for excitation and stabilisation of ultrasonic vibration known as autoresonance. An approach has been developed to design an autoresonant ultrasonic cutting unit as an oscillating system with an intelligent electronic feedback controlling self-excitation in the entire mechatronic system. The feedback produces the exciting force by means of transformation and amplification of the motion signal. This allows realisation for robust control of fine resonant tuning to bring the nonlinear high Q-factor systems into technological application. The autoresonant control provides the possibility of self-tuning and self-adaptation mechanisms for the system to keep the nonlinear resonant mode of oscillation under unpredictable variation of load, structure and parameters. This allows simple regulation of intensity of the process whilst keeping maximum efficiency at all times. An autoresonant system with supervisory computer control was developed, tested and used for the control of the piezoelectric transducer during ultrasonically assisted cutting. The system has been developed as combined analog-digital, where analog devices process the control signal, and parameters of the devices are controlled digitally by computer. The

  18. Applications of machine learning and high-dimensional visualization in cancer detection, diagnosis, and management.

    PubMed

    McCarthy, John F; Marx, Kenneth A; Hoffman, Patrick E; Gee, Alexander G; O'Neil, Philip; Ujwal, M L; Hotchkiss, John

    2004-05-01

    Recent technical advances in combinatorial chemistry, genomics, and proteomics have made available large databases of biological and chemical information that have the potential to dramatically improve our understanding of cancer biology at the molecular level. Such an understanding of cancer biology could have a substantial impact on how we detect, diagnose, and manage cancer cases in the clinical setting. One of the biggest challenges facing clinical oncologists is how to extract clinically useful knowledge from the overwhelming amount of raw molecular data that are currently available. In this paper, we discuss how the exploratory data analysis techniques of machine learning and high-dimensional visualization can be applied to extract clinically useful knowledge from a heterogeneous assortment of molecular data. After an introductory overview of machine learning and visualization techniques, we describe two proprietary algorithms (PURS and RadViz) that we have found to be useful in the exploratory analysis of large biological data sets. We next illustrate, by way of three examples, the applicability of these techniques to cancer detection, diagnosis, and management using three very different types of molecular data. We first discuss the use of our exploratory analysis techniques on proteomic mass spectroscopy data for the detection of ovarian cancer. Next, we discuss the diagnostic use of these techniques on gene expression data to differentiate between squamous and adenocarcinoma of the lung. Finally, we illustrate the use of such techniques in selecting from a database of chemical compounds those most effective in managing patients with melanoma versus leukemia.

  19. Towards smart energy systems: application of kernel machine regression for medium term electricity load forecasting.

    PubMed

    Alamaniotis, Miltiadis; Bargiotas, Dimitrios; Tsoukalas, Lefteri H

    2016-01-01

    Integration of energy systems with information technologies has facilitated the realization of smart energy systems that utilize information to optimize system operation. To that end, crucial in optimizing energy system operation is the accurate, ahead-of-time forecasting of load demand. In particular, load forecasting allows planning of system expansion, and decision making for enhancing system safety and reliability. In this paper, the application of two types of kernel machines for medium term load forecasting (MTLF) is presented and their performance is recorded based on a set of historical electricity load demand data. The two kernel machine models and more specifically Gaussian process regression (GPR) and relevance vector regression (RVR) are utilized for making predictions over future load demand. Both models, i.e., GPR and RVR, are equipped with a Gaussian kernel and are tested on daily predictions for a 30-day-ahead horizon taken from the New England Area. Furthermore, their performance is compared to the ARMA(2,2) model with respect to mean average percentage error and squared correlation coefficient. Results demonstrate the superiority of RVR over the other forecasting models in performing MTLF.

  20. The applications of machine learning algorithms in the modeling of estrogen-like chemicals.

    PubMed

    Liu, Huanxiang; Yao, Xiaojun; Gramatica, Paola

    2009-06-01

    Increasing concern is being shown by the scientific community, government regulators, and the public about endocrine-disrupting chemicals that, in the environment, are adversely affecting human and wildlife health through a variety of mechanisms, mainly estrogen receptor-mediated mechanisms of toxicity. Because of the large number of such chemicals in the environment, there is a great need for an effective means of rapidly assessing endocrine-disrupting activity in the toxicology assessment process. When faced with the challenging task of screening large libraries of molecules for biological activity, the benefits of computational predictive models based on quantitative structure-activity relationships to identify possible estrogens become immediately obvious. Recently, in order to improve the accuracy of prediction, some machine learning techniques were introduced to build more effective predictive models. In this review we will focus our attention on some recent advances in the use of these methods in modeling estrogen-like chemicals. The advantages and disadvantages of the machine learning algorithms used in solving this problem, the importance of the validation and performance assessment of the built models as well as their applicability domains will be discussed.

  1. Application of machine learning methodology for PET-based definition of lung cancer.

    PubMed

    Kerhet, A; Small, C; Quon, H; Riauka, T; Schrader, L; Greiner, R; Yee, D; McEwan, A; Roa, W

    2010-02-01

    We applied a learning methodology framework to assist in the threshold-based segmentation of non-small-cell lung cancer (NSCLC) tumours in positron-emission tomography-computed tomography (PET-CT) imaging for use in radiotherapy planning. Gated and standard free-breathing studies of two patients were independently analysed (four studies in total). Each study had a pet-ct and a treatment-planning ct image. The reference gross tumour volume (GTV) was identified by two experienced radiation oncologists who also determined reference standardized uptake value (SUV) thresholds that most closely approximated the GTV contour on each slice. A set of uptake distribution-related attributes was calculated for each PET slice. A machine learning algorithm was trained on a subset of the PET slices to cope with slice-to-slice variation in the optimal suv threshold: that is, to predict the most appropriate suv threshold from the calculated attributes for each slice. The algorithm's performance was evaluated using the remainder of the pet slices. A high degree of geometric similarity was achieved between the areas outlined by the predicted and the reference SUV thresholds (Jaccard index exceeding 0.82). No significant difference was found between the gated and the free-breathing results in the same patient. In this preliminary work, we demonstrated the potential applicability of a machine learning methodology as an auxiliary tool for radiation treatment planning in NSCLC.

  2. SMARTbot: A Behavioral Analysis Framework Augmented with Machine Learning to Identify Mobile Botnet Applications

    PubMed Central

    Karim, Ahmad; Salleh, Rosli; Khan, Muhammad Khurram

    2016-01-01

    Botnet phenomenon in smartphones is evolving with the proliferation in mobile phone technologies after leaving imperative impact on personal computers. It refers to the network of computers, laptops, mobile devices or tablets which is remotely controlled by the cybercriminals to initiate various distributed coordinated attacks including spam emails, ad-click fraud, Bitcoin mining, Distributed Denial of Service (DDoS), disseminating other malwares and much more. Likewise traditional PC based botnet, Mobile botnets have the same operational impact except the target audience is particular to smartphone users. Therefore, it is import to uncover this security issue prior to its widespread adaptation. We propose SMARTbot, a novel dynamic analysis framework augmented with machine learning techniques to automatically detect botnet binaries from malicious corpus. SMARTbot is a component based off-device behavioral analysis framework which can generate mobile botnet learning model by inducing Artificial Neural Networks’ back-propagation method. Moreover, this framework can detect mobile botnet binaries with remarkable accuracy even in case of obfuscated program code. The results conclude that, a classifier model based on simple logistic regression outperform other machine learning classifier for botnet apps’ detection, i.e 99.49% accuracy is achieved. Further, from manual inspection of botnet dataset we have extracted interesting trends in those applications. As an outcome of this research, a mobile botnet dataset is devised which will become the benchmark for future studies. PMID:26978523

  3. Graphene-enhanced environmentally-benign cutting fluids for high-performance micro-machining applications.

    PubMed

    Chu, Bryan; Singh, Eklavya; Koratkar, Nikhil; Samuel, Johnson

    2013-08-01

    A canola-based cutting oil enhanced with graphene platelet (GPL) additives has been developed to fulfill the need for environmentally benign cutting oils for high performance micro-machining applications. Carboxyl-functionalized graphene platelets are used to enable stable GPL dispersion in the polar oil. Three oil formulations consisting of 0.05%, 0.10% and 0.15% GPL by weight are tested. The GPL-laden canola oil is first characterized based on its kinematic viscosity, thermal conductivity and coefficient of friction. Micro-turning tests are then performed to study the effect of GPL loading on the cutting temperature, cutting force, and the surface finish of the part. All tested loadings improve the cooling and lubricating properties of the canola oil. For cooling, this improvement is seen to increase with GPL loading. In the case of lubrication, there appears to be an optimal loading of around 0.10%. The presence of GPL also leads to a decrease in the surface roughness of the micro-machined surface but this improvement drops with increased GPL loading.

  4. SMARTbot: A Behavioral Analysis Framework Augmented with Machine Learning to Identify Mobile Botnet Applications.

    PubMed

    Karim, Ahmad; Salleh, Rosli; Khan, Muhammad Khurram

    2016-01-01

    Botnet phenomenon in smartphones is evolving with the proliferation in mobile phone technologies after leaving imperative impact on personal computers. It refers to the network of computers, laptops, mobile devices or tablets which is remotely controlled by the cybercriminals to initiate various distributed coordinated attacks including spam emails, ad-click fraud, Bitcoin mining, Distributed Denial of Service (DDoS), disseminating other malwares and much more. Likewise traditional PC based botnet, Mobile botnets have the same operational impact except the target audience is particular to smartphone users. Therefore, it is import to uncover this security issue prior to its widespread adaptation. We propose SMARTbot, a novel dynamic analysis framework augmented with machine learning techniques to automatically detect botnet binaries from malicious corpus. SMARTbot is a component based off-device behavioral analysis framework which can generate mobile botnet learning model by inducing Artificial Neural Networks' back-propagation method. Moreover, this framework can detect mobile botnet binaries with remarkable accuracy even in case of obfuscated program code. The results conclude that, a classifier model based on simple logistic regression outperform other machine learning classifier for botnet apps' detection, i.e 99.49% accuracy is achieved. Further, from manual inspection of botnet dataset we have extracted interesting trends in those applications. As an outcome of this research, a mobile botnet dataset is devised which will become the benchmark for future studies. PMID:26978523

  5. SMARTbot: A Behavioral Analysis Framework Augmented with Machine Learning to Identify Mobile Botnet Applications.

    PubMed

    Karim, Ahmad; Salleh, Rosli; Khan, Muhammad Khurram

    2016-01-01

    Botnet phenomenon in smartphones is evolving with the proliferation in mobile phone technologies after leaving imperative impact on personal computers. It refers to the network of computers, laptops, mobile devices or tablets which is remotely controlled by the cybercriminals to initiate various distributed coordinated attacks including spam emails, ad-click fraud, Bitcoin mining, Distributed Denial of Service (DDoS), disseminating other malwares and much more. Likewise traditional PC based botnet, Mobile botnets have the same operational impact except the target audience is particular to smartphone users. Therefore, it is import to uncover this security issue prior to its widespread adaptation. We propose SMARTbot, a novel dynamic analysis framework augmented with machine learning techniques to automatically detect botnet binaries from malicious corpus. SMARTbot is a component based off-device behavioral analysis framework which can generate mobile botnet learning model by inducing Artificial Neural Networks' back-propagation method. Moreover, this framework can detect mobile botnet binaries with remarkable accuracy even in case of obfuscated program code. The results conclude that, a classifier model based on simple logistic regression outperform other machine learning classifier for botnet apps' detection, i.e 99.49% accuracy is achieved. Further, from manual inspection of botnet dataset we have extracted interesting trends in those applications. As an outcome of this research, a mobile botnet dataset is devised which will become the benchmark for future studies.

  6. Towards smart energy systems: application of kernel machine regression for medium term electricity load forecasting.

    PubMed

    Alamaniotis, Miltiadis; Bargiotas, Dimitrios; Tsoukalas, Lefteri H

    2016-01-01

    Integration of energy systems with information technologies has facilitated the realization of smart energy systems that utilize information to optimize system operation. To that end, crucial in optimizing energy system operation is the accurate, ahead-of-time forecasting of load demand. In particular, load forecasting allows planning of system expansion, and decision making for enhancing system safety and reliability. In this paper, the application of two types of kernel machines for medium term load forecasting (MTLF) is presented and their performance is recorded based on a set of historical electricity load demand data. The two kernel machine models and more specifically Gaussian process regression (GPR) and relevance vector regression (RVR) are utilized for making predictions over future load demand. Both models, i.e., GPR and RVR, are equipped with a Gaussian kernel and are tested on daily predictions for a 30-day-ahead horizon taken from the New England Area. Furthermore, their performance is compared to the ARMA(2,2) model with respect to mean average percentage error and squared correlation coefficient. Results demonstrate the superiority of RVR over the other forecasting models in performing MTLF. PMID:26835237

  7. Reverse time migration: A seismic processing application on the connection machine

    NASA Technical Reports Server (NTRS)

    Fiebrich, Rolf-Dieter

    1987-01-01

    The implementation of a reverse time migration algorithm on the Connection Machine, a massively parallel computer is described. Essential architectural features of this machine as well as programming concepts are presented. The data structures and parallel operations for the implementation of the reverse time migration algorithm are described. The algorithm matches the Connection Machine architecture closely and executes almost at the peak performance of this machine.

  8. Integration of probe systems in a nanopositioning and nanomeasuring machine

    NASA Astrophysics Data System (ADS)

    Jaeger, Gerd; Manske, Eberhard; Hausotte, Tino; Mastylo, Rostyslav; Buechner, Hans-Joachim; Gruenwald, Rainer; Fussl, Roland

    2005-02-01

    The paper describes the design of a high-precision three-dimensional nanopositioning and nanomeasuring machine (NPM-Machine). The NPM-Machine has been developed by the Institute of Process Measurement and Sensor Technology of the Technische Universität Ilmenau and manufactured by the SIOS Mežtechnik GmbH Ilmenau. The machine was successfully tested and continually improved in the last few years. The NPM-Machine has a resolution of less than 0,1 nm over the entire positioning and measuring range of 25 mm x 25 mm x 5 mm. An Abbe offset-free design and the application of a new concept for compensating systematic errors resulting from mechanical bearings provide extraordinary accuracy. An important part of the NPM-Machine is constituted by a mirror corner. The integration of several probe systems and Nanotools makes the NPM-Machine suitable for various tasks, such as large-area scanning probe microscopy, mask and wafer inspection, nanostructuring, biotechnology as well as measuring mechanical precision workpieces a.s.o. Various probe systems have been integrated into the NPM-Machines. The machines are operating successfully in several German and foreign institutes including the Physikalisch-Technische Bundesanstalt (PTB). The article gives basic information on the NPM-Machine and describes the mode of operation and the measurements by means of probe systems.

  9. [Application of target restoration space quantity and quantitative relation in precise esthetic prosthodontics].

    PubMed

    Haiyang, Yu; Tian, Luo

    2016-06-01

    Target restoration space (TRS) is the most precise space required for designing optimal prosthesis. TRS consists of an internal or external tooth space to confirm the esthetics and function of the final restoration. Therefore, assisted with quantitive analysis transfer, TRS quantitative analysis is a significant improvement for minimum tooth preparation. This article presents TRS quantity-related measurement, analysis, transfer, and internal relevance of three TR. classifications. Results reveal the close bond between precision and minimally invasive treatment. This study can be used to improve the comprehension and execution of precise esthetic prosthodontics. PMID:27526443

  10. Application of Vehicle Dynamic Modeling in Uavs for Precise Determination of Exterior Orientation

    NASA Astrophysics Data System (ADS)

    Khaghani, M.; Skaloud, J.

    2016-06-01

    Advances in unmanned aerial vehicles (UAV) and especially micro aerial vehicle (MAV) technology together with increasing quality and decreasing price of imaging devices have resulted in growing use of MAVs in photogrammetry. The practicality of MAV mapping is seriously enhanced with the ability to determine parameters of exterior orientation (EO) with sufficient accuracy, in both absolute and relative senses (change of attitude between successive images). While differential carrier phase GNSS satisfies cm-level positioning accuracy, precise attitude determination is essential for both direct sensor orientation (DiSO) and integrated sensor orientation (ISO) in corridor mapping or in block configuration imaging over surfaces with low texture. Limited cost, size, and weight of MAVs represent limitations on quality of onboard navigation sensors and puts emphasis on exploiting full capacity of available resources. Typically short flying times (10-30 minutes) also limit the possibility of estimating and/or correcting factors such as sensor misalignment and poor attitude initialization of inertial navigation system (INS). This research aims at increasing the accuracy of attitude determination in both absolute and relative senses with no extra sensors onboard. In comparison to classical INS/GNSS setup, novel approach is presented here to integrated state estimation, in which vehicle dynamic model (VDM) is used as the main process model. Such system benefits from available information from autopilot and physical properties of the platform in enhancing performance of determination of trajectory and parameters of exterior orientation consequently. The navigation system employs a differential carrier phase GNSS receiver and a micro electro-mechanical system (MEMS) grade inertial measurement unit (IMU), together with MAV control input from autopilot. Monte-Carlo simulation has been performed on trajectories for typical corridor mapping and block imaging. Results reveal

  11. Precise Point Positioning with Ionosphere Estimation and application of Regional Ionospheric Maps

    NASA Astrophysics Data System (ADS)

    Galera Monico, J. F.; Marques, H. A.; Rocha, G. D. D. C.

    2015-12-01

    The ionosphere is one of most difficult source of errors to be modelled in the GPS positioning, mainly when applying data collected by single frequency receivers. Considering Precise Point Positioning (PPP) with single frequency data the options available include, for example, the use of Klobuchar model or applying Global Ionosphere Maps (GIM). The GIM contains Vertical Electron Content (VTEC) values that are commonly estimated considering a global network with poor covering in certain regions. For this reason Regional Ionosphere Maps (RIM) have been developed considering local GNSS network, for instance, the La Plata Ionospheric Model (LPIM) developed inside the context of SIRGAS (Geocentric Reference System for Americas). The South American RIM are produced with data from nearly 50 GPS ground receivers and considering these maps are generated for each hour with spatial resolution of one degree it is expected to provide better accuracy in GPS positioning for such region. Another possibility to correct for ionosphere effects in the PPP is to apply the ionosphere estimation technique based on Kalman filter. In this case, the ionosphere can be treated as a stochastic process and a good initial guess is necessary what can be obtained from an ionospheric map. In this paper we present the methodology involved with ionosphere estimation by using Kalman filter and also the application of global and regional ionospheric maps in the PPP as first guess. The ionosphere estimation strategy was implemented in the house software called RT_PPP that is capable of accomplishing PPP either for single or dual frequency data. GPS data from Brazilian station near equatorial region were processed and results with regional maps were compared with those by using global maps. Improvements of the order 15% were observed. In case of ionosphere estimation, the estimated coordinates were compared with ionosphere free solution and after PPP convergence the results reached centimeter accuracy.

  12. Bioinformatics for precision medicine in oncology: principles and application to the SHIVA clinical trial

    PubMed Central

    Servant, Nicolas; Roméjon, Julien; Gestraud, Pierre; La Rosa, Philippe; Lucotte, Georges; Lair, Séverine; Bernard, Virginie; Zeitouni, Bruno; Coffin, Fanny; Jules-Clément, Gérôme; Yvon, Florent; Lermine, Alban; Poullet, Patrick; Liva, Stéphane; Pook, Stuart; Popova, Tatiana; Barette, Camille; Prud’homme, François; Dick, Jean-Gabriel; Kamal, Maud; Le Tourneau, Christophe; Barillot, Emmanuel; Hupé, Philippe

    2014-01-01

    Precision medicine (PM) requires the delivery of individually adapted medical care based on the genetic characteristics of each patient and his/her tumor. The last decade witnessed the development of high-throughput technologies such as microarrays and next-generation sequencing which paved the way to PM in the field of oncology. While the cost of these technologies decreases, we are facing an exponential increase in the amount of data produced. Our ability to use this information in daily practice relies strongly on the availability of an efficient bioinformatics system that assists in the translation of knowledge from the bench towards molecular targeting and diagnosis. Clinical trials and routine diagnoses constitute different approaches, both requiring a strong bioinformatics environment capable of (i) warranting the integration and the traceability of data, (ii) ensuring the correct processing and analyses of genomic data, and (iii) applying well-defined and reproducible procedures for workflow management and decision-making. To address the issues, a seamless information system was developed at Institut Curie which facilitates the data integration and tracks in real-time the processing of individual samples. Moreover, computational pipelines were developed to identify reliably genomic alterations and mutations from the molecular profiles of each patient. After a rigorous quality control, a meaningful report is delivered to the clinicians and biologists for the therapeutic decision. The complete bioinformatics environment and the key points of its implementation are presented in the context of the SHIVA clinical trial, a multicentric randomized phase II trial comparing targeted therapy based on tumor molecular profiling versus conventional therapy in patients with refractory cancer. The numerous challenges faced in practice during the setting up and the conduct of this trial are discussed as an illustration of PM application. PMID:24910641

  13. Application of troposphere model from NWP and GNSS data into real-time precise positioning

    NASA Astrophysics Data System (ADS)

    Wilgan, Karina; Hadas, Tomasz; Kazmierski, Kamil; Rohm, Witold; Bosy, Jaroslaw

    2016-04-01

    The tropospheric delay empirical models are usually functions of meteorological parameters (temperature, pressure and humidity). The application of standard atmosphere parameters or global models, such as GPT (global pressure/temperature) model or UNB3 (University of New Brunswick, version 3) model, may not be sufficient, especially for positioning in non-standard weather conditions. The possible solution is to use regional troposphere models based on real-time or near-real time measurements. We implement a regional troposphere model into the PPP (Precise Point Positioning) software GNSS-WARP (Wroclaw Algorithms for Real-time Positioning) developed at Wroclaw University of Environmental and Life Sciences. The software is capable of processing static and kinematic multi-GNSS data in real-time and post-processing mode and takes advantage of final IGS (International GNSS Service) products as well as IGS RTS (Real-Time Service) products. A shortcoming of PPP technique is the time required for the solution to converge. One of the reasons is the high correlation among the estimated parameters: troposphere delay, receiver clock offset and receiver height. To efficiently decorrelate these parameters, a significant change in satellite geometry is required. Alternative solution is to introduce the external high-quality regional troposphere delay model to constrain troposphere estimates. The proposed model consists of zenith total delays (ZTD) and mapping functions calculated from meteorological parameters from Numerical Weather Prediction model WRF (Weather Research and Forecasting) and ZTDs from ground-based GNSS stations using the least-squares collocation software COMEDIE (Collocation of Meteorological Data for Interpretation and Estimation of Tropospheric Pathdelays) developed at ETH Zurich.

  14. Application of expert systems for determination of machining parameters in milling operations

    NASA Astrophysics Data System (ADS)

    Tolouei-Rad, M.; Bidhendi, Essie

    1995-08-01

    An expert system has been developed which is capable of selecting appropriate cutting tools and determining required machining parameters for milling operations. One feature of this system which distinguishes it from conventional applications of expert systems is that it uses information stored in database files. This causes the existence of a limited umber of expertise rules stored in the knowledge base; bringing up the advantage of shorter running time for the system. Another advantage of this system is its ability to retrieve required information from computer-aided design (CAD) systems through an input file, run the program, and restore the resulting information in an output file without any user interaction. These advantages make it an ideal system to be used in computer-aided design and manufacturing (CAD/CAM) systems.

  15. A study pertaining to inertial energy storage machine designs for space applications

    NASA Technical Reports Server (NTRS)

    Zowarka, R. C.

    1981-01-01

    The preliminary design of a counterrotating fast discharge homopolar generator (HPG) and a counterrotating active rotary flux compressor (CARFC) for space application is reported. The HPG is a counterrotating spool-type homopolar with superconducting field coil excitation. It delivers a 20-ms, 145-kJ pulse to a magnetoplasmahydrodynamic thruster. The peak output current is 42.7 kA at 240 V. After 20 ms the current is 29.7 kA at 167 V. The CARFC delivers ten 50-kJ, 250 microsecond pulses at 50-ms interval to six Xenon flash lamps pumping an Nd glass laser. The flux compressor is counterrotating for torque compensation. Current is started in the machine with a 5-kV, 5-kJ pulse-charged capacitor. Both designs were based upon demonstrated technology. The sensitivity of the designs to technology that may be available in five to ten years was determined.

  16. An application of machine learning to the organization of institutional software repositories

    NASA Technical Reports Server (NTRS)

    Bailin, Sidney; Henderson, Scott; Truszkowski, Walt

    1993-01-01

    Software reuse has become a major goal in the development of space systems, as a recent NASA-wide workshop on the subject made clear. The Data Systems Technology Division of Goddard Space Flight Center has been working on tools and techniques for promoting reuse, in particular in the development of satellite ground support software. One of these tools is the Experiment in Libraries via Incremental Schemata and Cobweb (ElvisC). ElvisC applies machine learning to the problem of organizing a reusable software component library for efficient and reliable retrieval. In this paper we describe the background factors that have motivated this work, present the design of the system, and evaluate the results of its application.

  17. Potential application of machine vision technology to saffron (Crocus sativus L.) quality characterization.

    PubMed

    Kiani, Sajad; Minaei, Saeid

    2016-12-01

    Saffron quality characterization is an important issue in the food industry and of interest to the consumers. This paper proposes an expert system based on the application of machine vision technology for characterization of saffron and shows how it can be employed in practical usage. There is a correlation between saffron color and its geographic location of production and some chemical attributes which could be properly used for characterization of saffron quality and freshness. This may be accomplished by employing image processing techniques coupled with multivariate data analysis for quantification of saffron properties. Expert algorithms can be made available for prediction of saffron characteristics such as color as well as for product classification. PMID:27374547

  18. Investigations of the Radiative Drive Produced by the Sandia Z-Pinch Machine and its Applications

    NASA Astrophysics Data System (ADS)

    Aubrey, Joysree; Bowers, Richard; Peterson, Darrell

    2000-10-01

    The Z-Machine at Sandia National Laboratories in Albuquerque, New Mexico is a reliable and high-quality source of soft x-rays which can be used for a variety of applications in the study of physics phenomena. Radiation temperatures of 250 eV with pulse widths of 5 ns FWHM in a central target are typical. The x-rays are produced when the kinetic energy of an imploding cylindrical plasma sheath is converted to internal and radiative energy as it decelerates and stagnates against a central foam target. We have used two-dimensional Lagrangian and Eulerian codes to simulate the generation and transport of radiation in the system. Sensitivities of the calculational results to material properties (such as foam opacities) and various radiation models have been investigated. The results of these parameter studies are presented along with predictions of the spectral distribution of the radiation and the energy output as a function of time.

  19. Applications of Brain–Machine Interface Systems in Stroke Recovery and Rehabilitation

    PubMed Central

    Francisco, Gerard E.; Contreras-Vidal, Jose L.

    2014-01-01

    Stroke is a leading cause of disability, significantly impacting the quality of life (QOL) in survivors, and rehabilitation remains the mainstay of treatment in these patients. Recent engineering and technological advances such as brain-machine interfaces (BMI) and robotic rehabilitative devices are promising to enhance stroke neu-rorehabilitation, to accelerate functional recovery and improve QOL. This review discusses the recent applications of BMI and robotic-assisted rehabilitation in stroke patients. We present the framework for integrated BMI and robotic-assisted therapies, and discuss their potential therapeutic, assistive and diagnostic functions in stroke rehabilitation. Finally, we conclude with an outlook on the potential challenges and future directions of these neurotechnologies, and their impact on clinical rehabilitation. PMID:25110624

  20. Applications of Brain-Machine Interface Systems in Stroke Recovery and Rehabilitation.

    PubMed

    Venkatakrishnan, Anusha; Francisco, Gerard E; Contreras-Vidal, Jose L

    2014-06-01

    Stroke is a leading cause of disability, significantly impacting the quality of life (QOL) in survivors, and rehabilitation remains the mainstay of treatment in these patients. Recent engineering and technological advances such as brain-machine interfaces (BMI) and robotic rehabilitative devices are promising to enhance stroke neu-rorehabilitation, to accelerate functional recovery and improve QOL. This review discusses the recent applications of BMI and robotic-assisted rehabilitation in stroke patients. We present the framework for integrated BMI and robotic-assisted therapies, and discuss their potential therapeutic, assistive and diagnostic functions in stroke rehabilitation. Finally, we conclude with an outlook on the potential challenges and future directions of these neurotechnologies, and their impact on clinical rehabilitation. PMID:25110624

  1. Development of a precision indentation and scratching system with a tool force and displacement control module.

    PubMed

    Park, Jae-Jun; Kwon, Kihwan; Bang, Jinhyeok; Cho, Nahmgyoo; Han, Chang-Soo; Choi, Nak-Sam

    2007-04-01

    This article presents a tip-based micropatterning system with a precision device for measuring the machine force and the tool path. The machine force is obtained by a tool control module with a leaf spring and a capacitive displacement sensor. It is controlled to provide a force that ranges from 80 microN to 8 N. The force sensing unit, which is part of the module, is mounted on a PZT (PbZrTi) driven in-feed motion stage with a resolution of 1 nm. The work piece is set on an X-Y motion stage, and the position can be controlled with a tool path accuracy of 5 nm. Micropatterning and precision indentation experiments were performed, while the machined surfaces were examined by atomic force microscopy. From these results, the feasibility of the system for precise force-displacement control was verified for application in tip-based precision machining.

  2. Space applications of Automation, Robotics and Machine Intelligence Systems (ARAMIS). Volume 4: Application of ARAMIS capabilities to space project functional elements

    NASA Technical Reports Server (NTRS)

    Miller, R. H.; Minsky, M. L.; Smith, D. B. S.

    1982-01-01

    Applications of automation, robotics, and machine intelligence systems (ARAMIS) to space activities and their related ground support functions are studied, so that informed decisions can be made on which aspects of ARAMIS to develop. The specific tasks which will be required by future space project tasks are identified and the relative merits of these options are evaluated. The ARAMIS options defined and researched span the range from fully human to fully machine, including a number of intermediate options (e.g., humans assisted by computers, and various levels of teleoperation). By including this spectrum, the study searches for the optimum mix of humans and machines for space project tasks.

  3. Label-free screening of single biomolecules through resistive pulse sensing technology for precision medicine applications

    NASA Astrophysics Data System (ADS)

    Harrer, S.; Kim, S. C.; Schieber, C.; Kannam, S.; Gunn, N.; Moore, S.; Scott, D.; Bathgate, R.; Skafidas, S.; Wagner, J. M.

    2015-05-01

    Employing integrated nano- and microfluidic circuits for detecting and characterizing biological compounds through resistive pulse sensing technology is a vibrant area of research at the interface of biotechnology and nanotechnology. Resistive pulse sensing platforms can be customized to study virtually any particle of choice which can be threaded through a fluidic channel and enable label-free single-particle interrogation with the primary read-out signal being an electric current fingerprint. The ability to perform label-free molecular screening with single-molecule and even single binding site resolution makes resistive pulse sensing technology a powerful tool for analyzing the smallest units of biological systems and how they interact with each other on a molecular level. This task is at the core of experimental systems biology and in particular ‘omics research which in combination with next-generation DNA-sequencing and next-generation drug discovery and design forms the foundation of a novel disruptive medical paradigm commonly referred to as personalized medicine or precision medicine. DNA-sequencing has approached the 1000-Dollar-Genome milestone allowing for decoding a complete human genome with unmatched speed and at low cost. Increased sequencing efficiency yields massive amounts of genomic data. Analyzing this data in combination with medical and biometric health data eventually enables understanding the pathways from individual genes to physiological functions. Access to this information triggers fundamental questions for doctors and patients alike: what are the chances of an outbreak for a specific disease? Can individual risks be managed and if so how? Which drugs are available and how should they be applied? Could a new drug be tailored to an individual’s genetic predisposition fast and in an affordable way? In order to provide answers and real-life value to patients, the rapid evolvement of novel computing approaches for analyzing big data in

  4. New applications of the nanopositioning and nanomeasuring machine by using advanced tactile and non-tactile probes

    NASA Astrophysics Data System (ADS)

    Manske, E.; Hausotte, T.; Mastylo, R.; Machleidt, T.; Franke, K.-H.; Jäger, G.

    2007-02-01

    With the nanopositioning and nanomeasuring machine (NPM-Machine) developed at the Technische Universität Ilmenau, subnanometre resolution and nanometre uncertainty in a measuring volume of 25 × 25 × 5 mm3 have been demonstrated in the last few years. This machine allows the most various measuring problems to be solved. In practice, however, there are too many different requirements for sensing surfaces or for detecting structures. So, this paper deals with the development and also the improvement of several optical and tactile probes for application in the NPM-Machine. A focus probe with a spot size of approximately 0.5 µm, a working distance of 1.5 mm and a resolution of less than 1 nm was developed and adopted in the NPM-Machine. In the next step, the working distance was improved to exploit the full vertical range of the NPM-Machine of 5 mm. To realize tactile sensing, an atomic force probe and tactile stylus probe were developed on the basis of the focus probe. These probing systems can acquire measuring data only by scanning the surface sequentially and point-by-point. To increase data acquisition, we realized a sensor based on a white-light interference microscope and parallel sampling of 1600 × 1200 data points. First results of fringe evaluation with laser interferometer reference are presented.

  5. Space Applications of Automation, Robotics and Machine Intelligence Systems (ARAMIS). Volume 4: Supplement, Appendix 4.3: Candidate ARAMIS Capabilities

    NASA Technical Reports Server (NTRS)

    Miller, R. H.; Minsky, M. L.; Smith, D. B. S.

    1982-01-01

    Potential applications of automation, robotics, and machine intelligence systems (ARAMIS) to space activities, and to their related ground support functions, in the years 1985-2000, so that NASA may make informed decisions on which aspects of ARAMIS to develop. The study first identifies the specific tasks which will be required by future space projects. It then defines ARAMIS options which are candidates for those space project tasks, and evaluates the relative merits of these options. Finally, the study identifies promising applications of ARAMIS, and recommends specific areas for further research. The ARAMIS options defined and researched by the study group span the range from fully human to fully machine, including a number of intermediate options (e.g., humans assisted by computers, and various levels of teleoperation). By including this spectrum, the study searches for the optimum mix of humans and machines for space project tasks.

  6. Integrated Imaging and Vision Techniques for Industrial Inspection: A Special Issue on Machine Vision and Applications

    SciTech Connect

    Liu, Zheng; Ukida, H.; Ramuhalli, Pradeep; Forsyth, D. S.

    2010-06-05

    Imaging- and vision-based techniques play an important role in industrial inspection. The sophistication of the techniques assures high- quality performance of the manufacturing process through precise positioning, online monitoring, and real-time classification. Advanced systems incorporating multiple imaging and/or vision modalities provide robust solutions to complex situations and problems in industrial applications. A diverse range of industries, including aerospace, automotive, electronics, pharmaceutical, biomedical, semiconductor, and food/beverage, etc., have benefited from recent advances in multi-modal imaging, data fusion, and computer vision technologies. Many of the open problems in this context are in the general area of image analysis methodologies (preferably in an automated fashion). This editorial article introduces a special issue of this journal highlighting recent advances and demonstrating the successful applications of integrated imaging and vision technologies in industrial inspection.

  7. A restriction enzyme-powered autonomous DNA walking machine: its application for a highly sensitive electrochemiluminescence assay of DNA

    NASA Astrophysics Data System (ADS)

    Chen, Ying; Xiang, Yun; Yuan, Ruo; Chai, Yaqin

    2014-12-01

    The construction of a restriction enzyme (Nt.AlwI)-powered DNA walking machine and its application for highly sensitive detection of DNA are described. DNA nanostructure tracks containing four overhang sequences with electrochemiluminescence (ECL) labels and complementary to the walker (target DNA) are self-assembled on the sensing electrode. The walker hybridizes with the complementary sequences on the tracks and forms specific recognition sites for Nt.AlwI, which cleaves the overhang sequences, releases the ECL labels and enables directional movement of the walker along the tracks. The formation of the nanostructure tracks and the Nt.AlwI-assisted cleavage of the overhang sequences in the presence of the walker are verified by using polyacrylamide gel electrophoresis analysis and cyclic voltammetry. The successive movement of the walker on the nanostructure tracks leads to continuous removal of massive ECL labels from the sensing electrode, which results in a significantly amplified suppression of the ECL emission for highly sensitive detection of sequence-specific DNA down to 0.19 pM. Results show that this DNA walking machine can also offer single-base mismatch discrimination capability. The successful application of the DNA walking machine for sequence-specific DNA detection can thus offer new opportunities for molecular machines in biosensing applications.The construction of a restriction enzyme (Nt.AlwI)-powered DNA walking machine and its application for highly sensitive detection of DNA are described. DNA nanostructure tracks containing four overhang sequences with electrochemiluminescence (ECL) labels and complementary to the walker (target DNA) are self-assembled on the sensing electrode. The walker hybridizes with the complementary sequences on the tracks and forms specific recognition sites for Nt.AlwI, which cleaves the overhang sequences, releases the ECL labels and enables directional movement of the walker along the tracks. The formation of the

  8. Precision displacement reference system

    DOEpatents

    Bieg, Lothar F.; Dubois, Robert R.; Strother, Jerry D.

    2000-02-22

    A precision displacement reference system is described, which enables real time accountability over the applied displacement feedback system to precision machine tools, positioning mechanisms, motion devices, and related operations. As independent measurements of tool location is taken by a displacement feedback system, a rotating reference disk compares feedback counts with performed motion. These measurements are compared to characterize and analyze real time mechanical and control performance during operation.

  9. Application of the metrological scanning probe microscope for high-precision, long-range, traceable measurements

    NASA Astrophysics Data System (ADS)

    Dorozhovets, N.; Hausotte, T.; Jäger, G.; Manske, E.

    2007-06-01

    This paper presents measurements of calibrated step height and pitch standards using a homodyne interferometer-based metrological scanning probe microscope (SPM) and a nanopositioning and nanomeasuring machine (NPM machine). These devices were developed at the Institute of Process Measurement and Sensor Technology of the Technische Universität Ilmenau. Together these devices are capable of highly exact dimensional and traceable long-range positioning and measurement with a resolution of 0.1 nm over the positioning and measurement range of 25 mm × 25 mm × 5 mm. Measurements of different calibrated step height and pitch standards were completed in order to test the repeatability and accuracy of the metrological SPM. The deviations between the calibrated and measured values were smaller than the uncertainty values determined by the Physikalisch-Technische Bundesanstalt (PTB) calibration. The extended uncertainty of the measurement results (step height or mean pitch value) was less than 1 nm.

  10. The application of GPS precise point positioning technology in aerial triangulation

    NASA Astrophysics Data System (ADS)

    Yuan, Xiuxiao; Fu, Jianhong; Sun, Hongxing; Toth, Charles

    In traditional GPS-supported aerotriangulation, differential GPS (DGPS) positioning technology is used to determine the 3-dimensional coordinates of the perspective centers at exposure time with an accuracy of centimeter to decimeter level. This method can significantly reduce the number of ground control points (GCPs). However, the establishment of GPS reference stations for DGPS positioning is not only labor-intensive and costly, but also increases the implementation difficulty of aerial photography. This paper proposes aerial triangulation supported with GPS precise point positioning (PPP) as a way to avoid the use of the GPS reference stations and simplify the work of aerial photography. Firstly, we present the algorithm for GPS PPP in aerial triangulation applications. Secondly, the error law of the coordinate of perspective centers determined using GPS PPP is analyzed. Thirdly, based on GPS PPP and aerial triangulation software self-developed by the authors, four sets of actual aerial images taken from surveying and mapping projects, different in both terrain and photographic scale, are given as experimental models. The four sets of actual data were taken over a flat region at a scale of 1:2500, a mountainous region at a scale of 1:3000, a high mountainous region at a scale of 1:32000 and an upland region at a scale of 1:60000 respectively. In these experiments, the GPS PPP results were compared with results obtained through DGPS positioning and traditional bundle block adjustment. In this way, the empirical positioning accuracy of GPS PPP in aerial triangulation can be estimated. Finally, the results of bundle block adjustment with airborne GPS controls from GPS PPP are analyzed in detail. The empirical results show that GPS PPP applied in aerial triangulation has a systematic error of half-meter level and a stochastic error within a few decimeters. However, if a suitable adjustment solution is adopted, the systematic error can be eliminated in GPS

  11. A Digital Liquid State Machine With Biologically Inspired Learning and Its Application to Speech Recognition.

    PubMed

    Zhang, Yong; Li, Peng; Jin, Yingyezhe; Choe, Yoonsuck

    2015-11-01

    This paper presents a bioinspired digital liquid-state machine (LSM) for low-power very-large-scale-integration (VLSI)-based machine learning applications. To the best of the authors' knowledge, this is the first work that employs a bioinspired spike-based learning algorithm for the LSM. With the proposed online learning, the LSM extracts information from input patterns on the fly without needing intermediate data storage as required in offline learning methods such as ridge regression. The proposed learning rule is local such that each synaptic weight update is based only upon the firing activities of the corresponding presynaptic and postsynaptic neurons without incurring global communications across the neural network. Compared with the backpropagation-based learning, the locality of computation in the proposed approach lends itself to efficient parallel VLSI implementation. We use subsets of the TI46 speech corpus to benchmark the bioinspired digital LSM. To reduce the complexity of the spiking neural network model without performance degradation for speech recognition, we study the impacts of synaptic models on the fading memory of the reservoir and hence the network performance. Moreover, we examine the tradeoffs between synaptic weight resolution, reservoir size, and recognition performance and present techniques to further reduce the overhead of hardware implementation. Our simulation results show that in terms of isolated word recognition evaluated using the TI46 speech corpus, the proposed digital LSM rivals the state-of-the-art hidden Markov-model-based recognizer Sphinx-4 and outperforms all other reported recognizers including the ones that are based upon the LSM or neural networks.

  12. A Digital Liquid State Machine With Biologically Inspired Learning and Its Application to Speech Recognition.

    PubMed

    Zhang, Yong; Li, Peng; Jin, Yingyezhe; Choe, Yoonsuck

    2015-11-01

    This paper presents a bioinspired digital liquid-state machine (LSM) for low-power very-large-scale-integration (VLSI)-based machine learning applications. To the best of the authors' knowledge, this is the first work that employs a bioinspired spike-based learning algorithm for the LSM. With the proposed online learning, the LSM extracts information from input patterns on the fly without needing intermediate data storage as required in offline learning methods such as ridge regression. The proposed learning rule is local such that each synaptic weight update is based only upon the firing activities of the corresponding presynaptic and postsynaptic neurons without incurring global communications across the neural network. Compared with the backpropagation-based learning, the locality of computation in the proposed approach lends itself to efficient parallel VLSI implementation. We use subsets of the TI46 speech corpus to benchmark the bioinspired digital LSM. To reduce the complexity of the spiking neural network model without performance degradation for speech recognition, we study the impacts of synaptic models on the fading memory of the reservoir and hence the network performance. Moreover, we examine the tradeoffs between synaptic weight resolution, reservoir size, and recognition performance and present techniques to further reduce the overhead of hardware implementation. Our simulation results show that in terms of isolated word recognition evaluated using the TI46 speech corpus, the proposed digital LSM rivals the state-of-the-art hidden Markov-model-based recognizer Sphinx-4 and outperforms all other reported recognizers including the ones that are based upon the LSM or neural networks. PMID:25643415

  13. Application of Machine Learning Algorithms to the Study of Noise Artifacts in Gravitational-Wave Data

    NASA Technical Reports Server (NTRS)

    Biswas, Rahul; Blackburn, Lindy L.; Cao, Junwei; Essick, Reed; Hodge, Kari Alison; Katsavounidis, Erotokritos; Kim, Kyungmin; Young-Min, Kim; Le Bigot, Eric-Olivier; Lee, Chang-Hwan; Oh, John J.; Oh, Sang Hoon; Son, Edwin J.; Vaulin, Ruslan; Wang, Xiaoge; Ye, Tao

    2014-01-01

    The sensitivity of searches for astrophysical transients in data from the Laser Interferometer Gravitationalwave Observatory (LIGO) is generally limited by the presence of transient, non-Gaussian noise artifacts, which occur at a high-enough rate such that accidental coincidence across multiple detectors is non-negligible. Furthermore, non-Gaussian noise artifacts typically dominate over the background contributed from stationary noise. These "glitches" can easily be confused for transient gravitational-wave signals, and their robust identification and removal will help any search for astrophysical gravitational-waves. We apply Machine Learning Algorithms (MLAs) to the problem, using data from auxiliary channels within the LIGO detectors that monitor degrees of freedom unaffected by astrophysical signals. Terrestrial noise sources may manifest characteristic disturbances in these auxiliary channels, inducing non-trivial correlations with glitches in the gravitational-wave data. The number of auxiliary-channel parameters describing these disturbances may also be extremely large; high dimensionality is an area where MLAs are particularly well-suited. We demonstrate the feasibility and applicability of three very different MLAs: Artificial Neural Networks, Support Vector Machines, and Random Forests. These classifiers identify and remove a substantial fraction of the glitches present in two very different data sets: four weeks of LIGO's fourth science run and one week of LIGO's sixth science run. We observe that all three algorithms agree on which events are glitches to within 10% for the sixth science run data, and support this by showing that the different optimization criteria used by each classifier generate the same decision surface, based on a likelihood-ratio statistic. Furthermore, we find that all classifiers obtain similar limiting performance, suggesting that most of the useful information currently contained in the auxiliary channel parameters we extract

  14. High-resolution frequency-modulated continuous-wave laser ranging for precision distance metrology applications

    NASA Astrophysics Data System (ADS)

    Shi, Guang; Zhang, Fumin; Qu, Xinghua; Meng, Xiangsong

    2014-12-01

    Frequency-modulated continuous wave (FMCW) laser ranging is one of the most interesting techniques for precision distance metrology. In order to ensure the theoretical measurement range and precision, a narrow linewidth external cavity tunable laser with large tuning range is chosen. In practical situations, the tuning nonlinearity of the laser reduces the measurement precision, hence an auxiliary interferometer is used to measure the laser tuning rate and linearize the frequency ramp. Then, fast Fourier transform algorithm is applied to the resampled signal of the main interferometer, and the full-width at half maximum of the frequency spectrum is narrowed. In the end, the experiments are carried out using the FMCW laser ranging system and demonstrate 50-μm range resolution at 8.7 m.

  15. Precision of image-based registration for intraoperative navigation in the presence of metal artifacts: Application to corrective osteotomy surgery.

    PubMed

    Dobbe, J G G; Curnier, F; Rondeau, X; Streekstra, G J

    2015-06-01

    Navigation for corrective osteotomy surgery requires patient-to-image registration. When registration is based on intraoperative 3-D cone-beam CT (CBCT) imaging, metal landmarks may be used that deteriorate image quality. This study investigates whether metal artifacts influence the precision of image-to-patient registration, either with or without intermediate user intervention during the registration procedure, in an application for corrective osteotomy of the distal radius. A series of 3-D CBCT scans is made of a cadaver arm with and without metal landmarks. Metal artifact reduction (MAR) based on inpainting techniques is used to improve 3-D CBCT images hampered by metal artifacts. This provides three sets of images (with metal, with MAR, and without metal), which enable investigating the differences in precision of intraoperative registration. Gray-level based point-to-image registration showed a better correlation coefficient if intraoperative images with MAR are used, indicating a better image similarity. The precision of registration without intermediate user intervention during the registration procedure, expressed as the residual angulation and displacement error after repetitive registration was very low and showed no improvement when MAR was used. By adding intermediate user intervention to the registration procedure however, precision was very high but was not affected by the presence of metal artifacts in the specific application.

  16. Low-power smart vision system-on-a-chip design for ultrafast machine vision applications

    NASA Astrophysics Data System (ADS)

    Fang, Wai-Chi

    1998-03-01

    In this paper, an ultra-fast smart vision system-on-a-chip design is proposed to provide effective solutions for real time machine vision applications by taking advantages of recent advances in integrated sensing/processing designs, electronic neural networks, advanced microprocessors and sub- micron VLSI technology. The smart vision system mimics what is inherent in biological vision systems. It is programmable to perform vision processing in all levels such as image acquisition, image fusion, image analysis, and scene interpretation. A system-on-a-chip implementation of this smart vision system is shown to be feasible by integrating the whole system into a 3-cm by 3-cm chip design in a 0.18- micrometer CMOS technology. The system achieves one tea- operation-per-second computing power that is a two order-of- magnitude increase over the state-of-the-art microcomputer and DSP chips. Its high performance is due to massively parallel computing structures, high data throughput rates, fast learning capabilities, and advanced VLSI system-on-a-chip implementation. This highly integrated smart vision system can be used for various NASA scientific missions and other military, industrial or commercial vision applications.

  17. Study of Lighting Solutions in Machine Vision Applications for Automated Assembly Operations

    NASA Astrophysics Data System (ADS)

    Zorcolo, Alberto; Escobar-Palafox, Gustavo; Gault, Rosemary; Scott, Robin; Ridgway, Keith

    2011-12-01

    The application of machine vision techniques represents an invaluable aid in many fields of manufacturing, from part inspection to metrology, robot guidance and assembly operations in general. An effective illumination of the working area constitutes a crucial aspect for optimising the performance of such techniques but unfortunately ideal light conditions are rarely available, especially if the vision system has to work within small areas, possibly close to metallic surfaces with high reflectivity. This work aims to investigate which factors mostly affect the accuracy in a typical feature recognition and measurement application. A first screening of a set of six factors was carried out by testing three different light sources, according to a two-level fractional factorial design of experiments (DOE), a Pareto analysis was performed in order to establish which parameters were the most significant. Once the key factors were identified, a second series of the experiments were carried out on a single light source, in order to optimise the key parameters and to provide useful guidelines on how to minimise measurement errors in different scenarios.

  18. Size-confined growth of atom-precise nanoclusters in metal-organic frameworks and their catalytic applications

    NASA Astrophysics Data System (ADS)

    Liu, Lingli; Song, Yongbo; Chong, Hanbao; Yang, Sha; Xiang, Ji; Jin, Shan; Kang, Xi; Zhang, Jun; Yu, Haizhu; Zhu, Manzhou

    2016-01-01

    Using MOFs as size-selection templates, we have for the first time synthesized atom-precise Au11:PPh3 nanoclusters (NCs) and Au13Ag12:PPh3 NCs with high purity by a one-step, in situ reduction method. Specifically, we found that the product released from the frameworks of ZIF-8 is exclusively the Au11:PPh3 NCs rather than polydispersed NCs, and inside MIL-101(Cr) the Au13Ag12:PPh3 NCs constitute the exclusive product. The metal NC@MOF composites are also demonstrated for catalytic application. The high catalytic efficiency for the oxidation of benzyl alcohol indicates that atom-precise noble metal NCs@MOFs may act as a promising class of heterogeneous catalysts. The atom-precise NCs obtained in the MOF templated synthesis imply the future possibility of using MOFs of various pore sizes for the size-selective synthesis of atomically precise NCs. Meanwhile, metal NCs@MOFs will contribute to the understanding of the mechanism of nanocatalyst surface reactions and hence opens up enormous opportunities in heterogeneous catalysis.Using MOFs as size-selection templates, we have for the first time synthesized atom-precise Au11:PPh3 nanoclusters (NCs) and Au13Ag12:PPh3 NCs with high purity by a one-step, in situ reduction method. Specifically, we found that the product released from the frameworks of ZIF-8 is exclusively the Au11:PPh3 NCs rather than polydispersed NCs, and inside MIL-101(Cr) the Au13Ag12:PPh3 NCs constitute the exclusive product. The metal NC@MOF composites are also demonstrated for catalytic application. The high catalytic efficiency for the oxidation of benzyl alcohol indicates that atom-precise noble metal NCs@MOFs may act as a promising class of heterogeneous catalysts. The atom-precise NCs obtained in the MOF templated synthesis imply the future possibility of using MOFs of various pore sizes for the size-selective synthesis of atomically precise NCs. Meanwhile, metal NCs@MOFs will contribute to the understanding of the mechanism of nanocatalyst

  19. Multi-antenna synchronized global navigation satellite system receiver and its advantages in high-precision positioning applications

    NASA Astrophysics Data System (ADS)

    Dong, Danan; Chen, Wen; Cai, Miaomiao; Zhou, Feng; Wang, Minghua; Yu, Chao; Zheng, Zhengqi; Wang, Yuanfei

    2016-02-01

    The multi-antenna synchronized global navigation satellite system receiver is a high precision, low cost, and widely used emerging receiver. Using this type of receiver, the satellite and receiver clock errors can be eliminated simultaneously by forming between antenna single-differences, which is equivalent to the conventional double-difference model. However, current multi-antenna synchronized global navigation satellite system receiver products have not fully realized their potential to achieve better accuracy, efficiency, and broader applications. This paper introduces the conceptual design and derivable products of multi-antenna synchronized global navigation satellite system receivers involving the aspects of attitude determination, multipath effect mitigation, phase center variation correction, and ground-based carrier phase windup calibration. Through case studies, the advantages of multi-antenna synchronized global navigation satellite system receivers in high-precision positioning applications are demonstrated.

  20. Development of laser-guided precision sprayers for tree crop applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tree crops in nurseries and orchards have great variations in shapes, sizes, canopy densities and gaps between in-row trees. The variability requires future sprayers to be flexible to spray the amount of chemicals that can match tree structures. A precision air-assisted sprayer was developed to appl...

  1. Proceedings of the Sixteenth Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The effects of ionospheric and tropospheric propagation on time and frequency transfer, advances in the generation of precise time and frequency, time transfer techniques and filtering and modeling were among the topics emphasized. Rubidium and cesium frequency standard, crystal oscillators, masers, Kalman filters, and atomic clocks were discussed.

  2. Precision physics at LHC

    SciTech Connect

    Hinchliffe, I.

    1997-05-01

    In this talk the author gives a brief survey of some physics topics that will be addressed by the Large Hadron Collider currently under construction at CERN. Instead of discussing the reach of this machine for new physics, the author gives examples of the types of precision measurements that might be made if new physics is discovered.

  3. Topologies for three-phase wound-field salient rotor switched-flux machines for HEV applications

    NASA Astrophysics Data System (ADS)

    Khan, Faisal; Sulaiman, Erwan; Ahmad, Md Zarafi; Husin, Zhafir Aizat; Mazlan, Mohamed Mubin Aizat

    2015-05-01

    Wound-field switched-flux machines (WFSFM) have an intrinsic simplicity and high speed that make them well suited to many hybrid electric vehicle (HEV) applications. However, overlap armature and field windings raised the copper losses in these machines. Furthermore, in previous design segmented-rotor is used which made the rotor less robust. To overcome these problems, this paper presents novel topologies for three-phase wound-field switched-flux machines. Both armature and field winding are located on the stator and rotor is composed of only stack of iron. Non-overlap armature and field windings and toothed-rotor are the clear advantages of these topologies as the copper losses gets reduce and rotor becomes more robust. Design feasibility and performance analysis of 12 slots and different rotor pole numbers are examined on the basis of coil arrangement test, peak armature flux linkage, back emf, cogging torque and average torque by using Finite Element Analysis(FEA).

  4. Application of adaptive neuro-fuzzy inference system and cuckoo optimization algorithm for analyzing electro chemical machining process

    NASA Astrophysics Data System (ADS)

    Teimouri, Reza; Sohrabpoor, Hamed

    2013-12-01

    Electrochemical machining process (ECM) is increasing its importance due to some of the specific advantages which can be exploited during machining operation. The process offers several special privileges such as higher machining rate, better accuracy and control, and wider range of materials that can be machined. Contribution of too many predominate parameters in the process, makes its prediction and selection of optimal values really complex, especially while the process is programmized for machining of hard materials. In the present work in order to investigate effects of electrolyte concentration, electrolyte flow rate, applied voltage and feed rate on material removal rate (MRR) and surface roughness (SR) the adaptive neuro-fuzzy inference systems (ANFIS) have been used for creation predictive models based on experimental observations. Then the ANFIS 3D surfaces have been plotted for analyzing effects of process parameters on MRR and SR. Finally, the cuckoo optimization algorithm (COA) was used for selection solutions in which the process reaches maximum material removal rate and minimum surface roughness simultaneously. Results indicated that the ANFIS technique has superiority in modeling of MRR and SR with high prediction accuracy. Also, results obtained while applying of COA have been compared with those derived from confirmatory experiments which validate the applicability and suitability of the proposed techniques in enhancing the performance of ECM process.

  5. Apparatus for precision micromachining with lasers

    DOEpatents

    Chang, Jim J.; Dragon, Ernest P.; Warner, Bruce E.

    1998-01-01

    A new material processing apparatus using a short-pulsed, high-repetition-rate visible laser for precision micromachining utilizes a near diffraction limited laser, a high-speed precision two-axis tilt-mirror for steering the laser beam, an optical system for either focusing or imaging the laser beam on the part, and a part holder that may consist of a cover plate and a back plate. The system is generally useful for precision drilling, cutting, milling and polishing of metals and ceramics, and has broad application in manufacturing precision components. Precision machining has been demonstrated through percussion drilling and trepanning using this system. With a 30 W copper vapor laser running at multi-kHz pulse repetition frequency, straight parallel holes with size varying from 500 microns to less than 25 microns and with aspect ratios up to 1:40 have been consistently drilled with good surface finish on a variety of metals. Micromilling and microdrilling on ceramics using a 250 W copper vapor laser have also been demonstrated with good results. Materialogroaphic sections of machined parts show little (submicron scale) recast layer and heat affected zone.

  6. Apparatus for precision micromachining with lasers

    DOEpatents

    Chang, J.J.; Dragon, E.P.; Warner, B.E.

    1998-04-28

    A new material processing apparatus using a short-pulsed, high-repetition-rate visible laser for precision micromachining utilizes a near diffraction limited laser, a high-speed precision two-axis tilt-mirror for steering the laser beam, an optical system for either focusing or imaging the laser beam on the part, and a part holder that may consist of a cover plate and a back plate. The system is generally useful for precision drilling, cutting, milling and polishing of metals and ceramics, and has broad application in manufacturing precision components. Precision machining has been demonstrated through percussion drilling and trepanning using this system. With a 30 W copper vapor laser running at multi-kHz pulse repetition frequency, straight parallel holes with size varying from 500 microns to less than 25 microns and with aspect ratios up to 1:40 have been consistently drilled with good surface finish on a variety of metals. Micromilling and microdrilling on ceramics using a 250 W copper vapor laser have also been demonstrated with good results. Materialographic sections of machined parts show little (submicron scale) recast layer and heat affected zone. 1 fig.

  7. Drilling Precise Orifices and Slots

    NASA Technical Reports Server (NTRS)

    Richards, C. W.; Seidler, J. E.

    1983-01-01

    Reaction control thrustor injector requires precisely machined orifices and slots. Tooling setup consists of rotary table, numerical control system and torque sensitive drill press. Components used to drill oxidizer orifices. Electric discharge machine drills fuel-feed orifices. Device automates production of identical parts so several are completed in less time than previously.

  8. A review of the applications of data mining and machine learning for the prediction of biomedical properties of nanoparticles.

    PubMed

    Jones, David E; Ghandehari, Hamidreza; Facelli, Julio C

    2016-08-01

    This article presents a comprehensive review of applications of data mining and machine learning for the prediction of biomedical properties of nanoparticles of medical interest. The papers reviewed here present the results of research using these techniques to predict the biological fate and properties of a variety of nanoparticles relevant to their biomedical applications. These include the influence of particle physicochemical properties on cellular uptake, cytotoxicity, molecular loading, and molecular release in addition to manufacturing properties like nanoparticle size, and polydispersity. Overall, the results are encouraging and suggest that as more systematic data from nanoparticles becomes available, machine learning and data mining would become a powerful aid in the design of nanoparticles for biomedical applications. There is however the challenge of great heterogeneity in nanoparticles, which will make these discoveries more challenging than for traditional small molecule drug design. PMID:27282231

  9. A review of the applications of data mining and machine learning for the prediction of biomedical properties of nanoparticles.

    PubMed

    Jones, David E; Ghandehari, Hamidreza; Facelli, Julio C

    2016-08-01

    This article presents a comprehensive review of applications of data mining and machine learning for the prediction of biomedical properties of nanoparticles of medical interest. The papers reviewed here present the results of research using these techniques to predict the biological fate and properties of a variety of nanoparticles relevant to their biomedical applications. These include the influence of particle physicochemical properties on cellular uptake, cytotoxicity, molecular loading, and molecular release in addition to manufacturing properties like nanoparticle size, and polydispersity. Overall, the results are encouraging and suggest that as more systematic data from nanoparticles becomes available, machine learning and data mining would become a powerful aid in the design of nanoparticles for biomedical applications. There is however the challenge of great heterogeneity in nanoparticles, which will make these discoveries more challenging than for traditional small molecule drug design.

  10. Application and testing of additive manufacturing for mirrors and precision structures

    NASA Astrophysics Data System (ADS)

    Sweeney, Michael; Acreman, Martyn; Vettese, Tom; Myatt, Ray; Thompson, Mike

    2015-09-01

    Additive Manufacturing (aka AM, and 3-D printing) is widely touted in the media as the foundation for the next industrial revolution. Beneath the hype, AM does indeed offer profound advantages in lead-time, dramatically reduced consumption of expensive raw materials, while enabling new and innovative design forms that cannot be produced by other means. General Dynamics and their industry partners have begun to embrace this technology for mirrors and precision structures used in the aerospace, defense, and precision optical instrumentation industries. Aggressively lightweighted, open and closed back test mirror designs, 75-150 mm in size, were first produced by AM from several different materials. Subsequent optical finishing and test experiments have exceeded expectations for density, surface finish, dimensional stability and isotropy of thermal expansion on the optical scale of measurement. Materials currently under examination include aluminum, titanium, beryllium, aluminum beryllium, Inconel 625, stainless steel/bronze, and PEKK polymer.

  11. High precision (14 bit), high density (octal) analog to digital converter for spectroscopy applications.

    PubMed

    Subramaniam, E T; Jain, Mamta; Bhowmik, R K; Tripon, Michel

    2008-10-01

    Nuclear and particle physics experiments with large number of detectors require signal processing and data collection strategies that call for the ability to collect large amount of data while not sacrificing the precision and accuracy of the data being collected. This paper deals with the development of a high precision pulse peak detection, analog to digital converter (ADC) module with eight independent channels in plug-in daughter card motherboard model, best suited for spectroscopy experiments. This module provides multiple channels without cross-talk and of 14 bit resolution, while maintaining high density (each daughter card has an area of just 4.2(")x0.51(")) and exhibiting excellent integral nonlinearity (< or = +/-2 mV or +/-0.02% full scale reading) and differential nonlinearity (< or = +/-1%). It was designed, developed and tested, in house, and gives added advantages of cost effectiveness and ease of maintenance. PMID:19044710

  12. High precision (14 bit), high density (octal) analog to digital converter for spectroscopy applications

    NASA Astrophysics Data System (ADS)

    Subramaniam, E. T.; Jain, Mamta; Bhowmik, R. K.; Tripon, Michel

    2008-10-01

    Nuclear and particle physics experiments with large number of detectors require signal processing and data collection strategies that call for the ability to collect large amount of data while not sacrificing the precision and accuracy of the data being collected. This paper deals with the development of a high precision pulse peak detection, analog to digital converter (ADC) module with eight independent channels in plug-in daughter card motherboard model, best suited for spectroscopy experiments. This module provides multiple channels without cross-talk and of 14 bit resolution, while maintaining high density (each daughter card has an area of just 4.2″×0.51″) and exhibiting excellent integral nonlinearity (≤±2 mV or ±0.02% full scale reading) and differential nonlinearity (≤±1%). It was designed, developed and tested, in house, and gives added advantages of cost effectiveness and ease of maintenance.

  13. Precision enhancement in boundary element methods with application to electron optics.

    PubMed

    Loyd, Jody S; Gregory, Don A

    2016-08-01

    A hybrid approach is presented for obtaining electric potentials for use in electron optics modeling. An initial solution from the boundary element method (BEM) is used to derive the bounding potential of a cylindrical subdomain subsequently used in a Fourier series solution. The approach combines the inherent precision of this analytic solution with the flexibility of BEM to describe practical, non-idealized systems of electrodes. The resulting lens field in the Fourier series subdomain is of higher precision, thereby allowing smaller errors in subsequent calculations of electron ray paths. The effects of aberrations are thus easier to observe in tracing non-paraxial rays. Example ray-traces through a simple, known einzel lens are given as validation of this approach.

  14. Precision enhancement in boundary element methods with application to electron optics.

    PubMed

    Loyd, Jody S; Gregory, Don A

    2016-08-01

    A hybrid approach is presented for obtaining electric potentials for use in electron optics modeling. An initial solution from the boundary element method (BEM) is used to derive the bounding potential of a cylindrical subdomain subsequently used in a Fourier series solution. The approach combines the inherent precision of this analytic solution with the flexibility of BEM to describe practical, non-idealized systems of electrodes. The resulting lens field in the Fourier series subdomain is of higher precision, thereby allowing smaller errors in subsequent calculations of electron ray paths. The effects of aberrations are thus easier to observe in tracing non-paraxial rays. Example ray-traces through a simple, known einzel lens are given as validation of this approach. PMID:27068123

  15. Clinical Application of a Modular Genomics Technique in Systemic Lupus Erythematosus: Progress towards Precision Medicine.

    PubMed

    Zollars, Eric; Courtney, Sean M; Wolf, Bethany J; Allaire, Norm; Ranger, Ann; Hardiman, Gary; Petri, Michelle

    2016-01-01

    Monitoring disease activity in a complex, heterogeneous disease such as lupus is difficult. Both over- and undertreatment lead to damage. Current standard of care serologies are unreliable. Better measures of disease activity are necessary as we move into the era of precision medicine. We show here the use of a data-driven, modular approach to genomic biomarker development within lupus-specifically lupus nephritis. PMID:27656648

  16. Clinical Application of a Modular Genomics Technique in Systemic Lupus Erythematosus: Progress towards Precision Medicine

    PubMed Central

    Wolf, Bethany J.; Allaire, Norm; Ranger, Ann; Hardiman, Gary; Petri, Michelle

    2016-01-01

    Monitoring disease activity in a complex, heterogeneous disease such as lupus is difficult. Both over- and undertreatment lead to damage. Current standard of care serologies are unreliable. Better measures of disease activity are necessary as we move into the era of precision medicine. We show here the use of a data-driven, modular approach to genomic biomarker development within lupus—specifically lupus nephritis. PMID:27656648

  17. Clinical Application of a Modular Genomics Technique in Systemic Lupus Erythematosus: Progress towards Precision Medicine

    PubMed Central

    Wolf, Bethany J.; Allaire, Norm; Ranger, Ann; Hardiman, Gary; Petri, Michelle

    2016-01-01

    Monitoring disease activity in a complex, heterogeneous disease such as lupus is difficult. Both over- and undertreatment lead to damage. Current standard of care serologies are unreliable. Better measures of disease activity are necessary as we move into the era of precision medicine. We show here the use of a data-driven, modular approach to genomic biomarker development within lupus—specifically lupus nephritis.

  18. Precision laser range finder system design for Advanced Technology Laboratory applications

    NASA Technical Reports Server (NTRS)

    Golden, K. E.; Kohn, R. L.; Seib, D. H.

    1974-01-01

    Preliminary system design of a pulsed precision ruby laser rangefinder system is presented which has a potential range resolution of 0.4 cm when atmospheric effects are negligible. The system being proposed for flight testing on the advanced technology laboratory (ATL) consists of a modelocked ruby laser transmitter, course and vernier rangefinder receivers, optical beacon retroreflector tracking system, and a network of ATL tracking retroreflectors. Performance calculations indicate that spacecraft to ground ranging accuracies of 1 to 2 cm are possible.

  19. Precision Cleaning and Verification Processes Used at Marshall Space Flight Center for Critical Hardware Applications

    NASA Technical Reports Server (NTRS)

    Caruso, Salvadore V.

    1999-01-01

    Marshall Space Flight Center (MSFC) of the National Aeronautics and Space Administration (NASA) performs many research and development programs that require hardware and assemblies to be cleaned to levels that are compatible with fuels and oxidizers (liquid oxygen, solid propellants, etc.). Also, the Center is responsible for developing large telescope satellites which requires a variety of optical systems to be cleaned. A precision cleaning shop is operated with-in MSFC by the Fabrication Services Division of the Materials & Processes Division. Verification of cleanliness is performed for all precision cleaned articles in the Analytical Chemistry Branch. Since the Montreal Protocol was instituted, MSFC had to find substitutes for many materials that has been in use for many years, including cleaning agents and organic solvents. As MSFC is a research Center, there is a great variety of hardware that is processed in the Precision Cleaning Shop. This entails the use of many different chemicals and solvents, depending on the nature and configuration of the hardware and softgoods being cleaned. A review of the manufacturing cleaning and verification processes, cleaning materials and solvents used at MSFC and changes that resulted from the Montreal Protocol will be presented.

  20. Precision Cleaning and Verification Processes Used at Marshall Space Flight Center for Critical Hardware Applications

    NASA Technical Reports Server (NTRS)

    Caruso, Salvadore V.; Cox, Jack A.; McGee, Kathleen A.

    1998-01-01

    Marshall Space Flight Center (MSFC) of the National Aeronautics and Space Administration performs many research and development programs that require hardware and assemblies to be cleaned to levels that are compatible with fuels and oxidizers (liquid oxygen, solid propellants, etc.). Also, MSFC is responsible for developing large telescope satellites which require a variety of optical systems to be cleaned. A precision cleaning shop is operated within MSFC by the Fabrication Services Division of the Materials & Processes Laboratory. Verification of cleanliness is performed for all precision cleaned articles in the Environmental and Analytical Chemistry Branch. Since the Montreal Protocol was instituted, MSFC had to find substitutes for many materials that have been in use for many years, including cleaning agents and organic solvents. As MSFC is a research center, there is a great variety of hardware that is processed in the Precision Cleaning Shop. This entails the use of many different chemicals and solvents, depending on the nature and configuration of the hardware and softgoods being cleaned. A review of the manufacturing cleaning and verification processes, cleaning materials and solvents used at MSFC and changes that resulted from the Montreal Protocol will be presented.

  1. Deep Convolutional Extreme Learning Machine and Its Application in Handwritten Digit Classification

    PubMed Central

    Yang, Xinyi

    2016-01-01

    In recent years, some deep learning methods have been developed and applied to image classification applications, such as convolutional neuron network (CNN) and deep belief network (DBN). However they are suffering from some problems like local minima, slow convergence rate, and intensive human intervention. In this paper, we propose a rapid learning method, namely, deep convolutional extreme learning machine (DC-ELM), which combines the power of CNN and fast training of ELM. It uses multiple alternate convolution layers and pooling layers to effectively abstract high level features from input images. Then the abstracted features are fed to an ELM classifier, which leads to better generalization performance with faster learning speed. DC-ELM also introduces stochastic pooling in the last hidden layer to reduce dimensionality of features greatly, thus saving much training time and computation resources. We systematically evaluated the performance of DC-ELM on two handwritten digit data sets: MNIST and USPS. Experimental results show that our method achieved better testing accuracy with significantly shorter training time in comparison with deep learning methods and other ELM methods. PMID:27610128

  2. Robust vertical scanning white-light interferometry in close-to-machine applications

    NASA Astrophysics Data System (ADS)

    Tereschenko, Stanislav; Lehmann, Peter; Gollor, Pascal; Kuehnhold, Peter

    2015-05-01

    We present a scanning white-light interferometer (SWLI) for close-to-machine applications in the presence of environmental vibrations. It combines an area measuring white-light interferometer and a punctual measuring laser distance interferometer (LDI) in one device. The measurement spot of the LDI is within the field of view of SWLI. The LDI measures any distance change during the white-light measurement with a high temporal resolution. With the knowledge of the real distance changes during the measurement we can compensate for the influence of environmental vibrations on the white-light correlograms. The reconstruction of the white-light interference signals takes place after measurement by reordering the captured images in accordance with their real positions obtained by the LDI. With this system we are able to reconstruct completely distorted and unusable SWLI signals and to determine the 3D topography of the measurement specimen from these reconstructed signals with high accuracy. We demonstrate the feasibility of the method by examples of practical measurements with and without vibrational disturbances.

  3. Smart Interpretation - Application of Machine Learning in Geological Interpretation of AEM Data

    NASA Astrophysics Data System (ADS)

    Bach, T.; Gulbrandsen, M. L.; Jacobsen, R.; Pallesen, T. M.; Jørgensen, F.; Høyer, A. S.; Hansen, T. M.

    2015-12-01

    When using airborne geophysical measurements in e.g. groundwater mapping, an overwhelming amount of data is collected. Increasingly larger survey areas, denser data collection and limited resources, combines to an increasing problem of building geological models that use all the available data in a manner that is consistent with the geologists knowledge about the geology of the survey area. In the ERGO project, funded by The Danish National Advanced Technology Foundation, we address this problem, by developing new, usable tools, enabling the geologist utilize her geological knowledge directly in the interpretation of the AEM data, and thereby handle the large amount of data, In the project we have developed the mathematical basis for capturing geological expertise in a statistical model. Based on this, we have implemented new algorithms that have been operationalized and embedded in user friendly software. In this software, the machine learning algorithm, Smart Interpretation, enables the geologist to use the system as an assistant in the geological modelling process. As the software 'learns' the geology from the geologist, the system suggest new modelling features in the data. In this presentation we demonstrate the application of the results from the ERGO project, including the proposed modelling workflow utilized on a variety of data examples.

  4. Deep Convolutional Extreme Learning Machine and Its Application in Handwritten Digit Classification.

    PubMed

    Pang, Shan; Yang, Xinyi

    2016-01-01

    In recent years, some deep learning methods have been developed and applied to image classification applications, such as convolutional neuron network (CNN) and deep belief network (DBN). However they are suffering from some problems like local minima, slow convergence rate, and intensive human intervention. In this paper, we propose a rapid learning method, namely, deep convolutional extreme learning machine (DC-ELM), which combines the power of CNN and fast training of ELM. It uses multiple alternate convolution layers and pooling layers to effectively abstract high level features from input images. Then the abstracted features are fed to an ELM classifier, which leads to better generalization performance with faster learning speed. DC-ELM also introduces stochastic pooling in the last hidden layer to reduce dimensionality of features greatly, thus saving much training time and computation resources. We systematically evaluated the performance of DC-ELM on two handwritten digit data sets: MNIST and USPS. Experimental results show that our method achieved better testing accuracy with significantly shorter training time in comparison with deep learning methods and other ELM methods.

  5. Adaptive changes of rhythmic EEG oscillations in space implications for brain-machine interface applications.

    PubMed

    Cheron, G; Cebolla, A M; Petieau, M; Bengoetxea, A; Palmero-Soler, E; Leroy, A; Dan, B

    2009-01-01

    The dramatic development of brain machine interfaces has enhanced the use of human brain signals conveying mental action for controlling external actuators. This chapter will outline current evidences that the rhythmic electroencephalographic activity of the brain is sensitive to microgravity environment. Experiments performed in the International Space Station have shown significant changes in the power of the astronauts' alpha and mu oscillations in resting condition, and other adaptive modifications in the beta and gamma frequency range during the immersion in virtual navigation. In this context, the dynamic aspects of the resting or default condition of the awaken brain, the influence of the "top-down" dynamics, and the possibility to use a more constrained configuration by a new somatosensory-evoked potential (gating approach) are discussed in the sense of future uses of brain computing interface in space mission. Although, the state of the art of the noninvasive BCI approach clearly demonstrates their ability and the great expectance in the field of rehabilitation for the restoration of defective communication between the brain and external world, their future application in space mission urgently needs a better understanding of brain neurophysiology, in particular in aspects related to neural network rhythmicity in microgravity. PMID:19607999

  6. Control of Two Permanent Magnet Machines Using a Five-Leg Inverter for Automotive Applications

    SciTech Connect

    Su, Gui-Jia; Tang, Lixin; Huang, Xianghui

    2006-01-01

    This paper presents digital control schemes for control of two permanent magnet (PM) machines in an integrated traction and air-conditioning compressor drive system for automotive applications. The integrated drive system employs a five-leg inverter to power a three-phase traction PM motor and a two-phase compressor PM motor by tying the common terminal of the two-phase motor to the neutral point of the three-phase motor. Compared to a three-phase or a standalone two-phase inverter, it eliminates one phase leg and shares the control electronics between the two drives, thus significantly reducing the component count of the compressor drive. To demonstrate that the speed and torque of the two PM motors can be controlled independently, a control strategy was implemented in a digital signal processor, which includes a rotor flux field orientation based control (RFOC) for the three-phase motor, a similar RFOC and a position sensorless control in the brushless dc (BLDC) mode for the two-phase motor. Control implementation issues unique to a two-phase PM motor are also discussed. Test results with the three-phase motor running in the ac synchronous (ACS) mode while the two-phase motor either in the ACS or the BLDC mode are included to verify the independent speed and torque control capability of the integrated drive.

  7. Deep Convolutional Extreme Learning Machine and Its Application in Handwritten Digit Classification

    PubMed Central

    Yang, Xinyi

    2016-01-01

    In recent years, some deep learning methods have been developed and applied to image classification applications, such as convolutional neuron network (CNN) and deep belief network (DBN). However they are suffering from some problems like local minima, slow convergence rate, and intensive human intervention. In this paper, we propose a rapid learning method, namely, deep convolutional extreme learning machine (DC-ELM), which combines the power of CNN and fast training of ELM. It uses multiple alternate convolution layers and pooling layers to effectively abstract high level features from input images. Then the abstracted features are fed to an ELM classifier, which leads to better generalization performance with faster learning speed. DC-ELM also introduces stochastic pooling in the last hidden layer to reduce dimensionality of features greatly, thus saving much training time and computation resources. We systematically evaluated the performance of DC-ELM on two handwritten digit data sets: MNIST and USPS. Experimental results show that our method achieved better testing accuracy with significantly shorter training time in comparison with deep learning methods and other ELM methods.

  8. Deep Convolutional Extreme Learning Machine and Its Application in Handwritten Digit Classification.

    PubMed

    Pang, Shan; Yang, Xinyi

    2016-01-01

    In recent years, some deep learning methods have been developed and applied to image classification applications, such as convolutional neuron network (CNN) and deep belief network (DBN). However they are suffering from some problems like local minima, slow convergence rate, and intensive human intervention. In this paper, we propose a rapid learning method, namely, deep convolutional extreme learning machine (DC-ELM), which combines the power of CNN and fast training of ELM. It uses multiple alternate convolution layers and pooling layers to effectively abstract high level features from input images. Then the abstracted features are fed to an ELM classifier, which leads to better generalization performance with faster learning speed. DC-ELM also introduces stochastic pooling in the last hidden layer to reduce dimensionality of features greatly, thus saving much training time and computation resources. We systematically evaluated the performance of DC-ELM on two handwritten digit data sets: MNIST and USPS. Experimental results show that our method achieved better testing accuracy with significantly shorter training time in comparison with deep learning methods and other ELM methods. PMID:27610128

  9. Machine Tool Advanced Skills Technology (MAST). Common Ground: Toward a Standards-Based Training System for the U.S. Machine Tool and Metal Related Industries. Volume 3: Machining, of a 15-Volume Set of Skill Standards and Curriculum Training Materials for the Precision Manufacturing Industry.

    ERIC Educational Resources Information Center

    Texas State Technical Coll., Waco.

    This document is intended to help education and training institutions deliver the Machine Tool Advanced Skills Technology (MAST) curriculum to a variety of individuals and organizations. MAST consists of industry-specific skill standards and model curricula for 15 occupational specialty areas within the U.S. machine tool and metals-related…

  10. Machine Tool Advanced Skills Technology (MAST). Common Ground: Toward a Standards-Based Training System for the U.S. Machine Tool and Metal Related Industries. Volume 13: Laser Machining, of a 15-Volume Set of Skill Standards and Curriculum Training Materials for the Precision Manufacturing Industry.

    ERIC Educational Resources Information Center

    Texas State Technical Coll., Waco.

    This document is intended to help education and training institutions deliver the Machine Tool Advanced Skills Technology (MAST) curriculum to a variety of individuals and organizations. MAST consists of industry-specific skill standards and model curricula for 15 occupational specialty areas within the U.S. machine tool and metals-related…

  11. Application of machine learning algorithms to the study of noise artifacts in gravitational-wave data

    NASA Astrophysics Data System (ADS)

    Biswas, Rahul; Blackburn, Lindy; Cao, Junwei; Essick, Reed; Hodge, Kari Alison; Katsavounidis, Erotokritos; Kim, Kyungmin; Kim, Young-Min; Le Bigot, Eric-Olivier; Lee, Chang-Hwan; Oh, John J.; Oh, Sang Hoon; Son, Edwin J.; Tao, Ye; Vaulin, Ruslan; Wang, Xiaoge

    2013-09-01

    The sensitivity of searches for astrophysical transients in data from the Laser Interferometer Gravitational-wave Observatory (LIGO) is generally limited by the presence of transient, non-Gaussian noise artifacts, which occur at a high enough rate such that accidental coincidence across multiple detectors is non-negligible. These “glitches” can easily be mistaken for transient gravitational-wave signals, and their robust identification and removal will help any search for astrophysical gravitational waves. We apply machine-learning algorithms (MLAs) to the problem, using data from auxiliary channels within the LIGO detectors that monitor degrees of freedom unaffected by astrophysical signals. Noise sources may produce artifacts in these auxiliary channels as well as the gravitational-wave channel. The number of auxiliary-channel parameters describing these disturbances may also be extremely large; high dimensionality is an area where MLAs are particularly well suited. We demonstrate the feasibility and applicability of three different MLAs: artificial neural networks, support vector machines, and random forests. These classifiers identify and remove a substantial fraction of the glitches present in two different data sets: four weeks of LIGO’s fourth science run and one week of LIGO’s sixth science run. We observe that all three algorithms agree on which events are glitches to within 10% for the sixth-science-run data, and support this by showing that the different optimization criteria used by each classifier generate the same decision surface, based on a likelihood-ratio statistic. Furthermore, we find that all classifiers obtain similar performance to the benchmark algorithm, the ordered veto list, which is optimized to detect pairwise correlations between transients in LIGO auxiliary channels and glitches in the gravitational-wave data. This suggests that most of the useful information currently extracted from the auxiliary channels is already described

  12. Extensions and applications of ensemble-of-trees methods in machine learning

    NASA Astrophysics Data System (ADS)

    Bleich, Justin

    Ensemble-of-trees algorithms have emerged to the forefront of machine learning due to their ability to generate high forecasting accuracy for a wide array of regression and classification problems. Classic ensemble methodologies such as random forests (RF) and stochastic gradient boosting (SGB) rely on algorithmic procedures to generate fits to data. In contrast, more recent ensemble techniques such as Bayesian Additive Regression Trees (BART) and Dynamic Trees (DT) focus on an underlying Bayesian probability model to generate the fits. These new probability model-based approaches show much promise versus their algorithmic counterparts, but also offer substantial room for improvement. The first part of this thesis focuses on methodological advances for ensemble-of-trees techniques with an emphasis on the more recent Bayesian approaches. In particular, we focus on extensions of BART in four distinct ways. First, we develop a more robust implementation of BART for both research and application. We then develop a principled approach to variable selection for BART as well as the ability to naturally incorporate prior information on important covariates into the algorithm. Next, we propose a method for handling missing data that relies on the recursive structure of decision trees and does not require imputation. Last, we relax the assumption of homoskedasticity in the BART model to allow for parametric modeling of heteroskedasticity. The second part of this thesis returns to the classic algorithmic approaches in the context of classification problems with asymmetric costs of forecasting errors. First we consider the performance of RF and SGB more broadly and demonstrate its superiority to logistic regression for applications in criminology with asymmetric costs. Next, we use RF to forecast unplanned hospital readmissions upon patient discharge with asymmetric costs taken into account. Finally, we explore the construction of stable decision trees for forecasts of

  13. Application of Abrasive-Waterjets for Machining Fatigue-Critical Aircraft Aluminum Parts

    SciTech Connect

    Liu, H T; Hovanski, Yuri; Dahl, Michael E; Zeng, J

    2010-08-19

    Current specifications require AWJ-cut aluminum parts for fatigue critical aerospace structures to go through subsequent processing due to concerns of degradation in fatigue performance. The requirement of secondary process for AWJ-machined parts greatly negates the cost effectiveness of waterjet technology. Some cost savings are envisioned if it can be shown that AWJ net cut parts have comparable durability properties as those conventionally machined. To revisit and upgrade the specifications for AWJ machining of aircraft aluminum, “Dog-bone” specimens, with and without secondary processes, were prepared for independent fatigue tests at Boeing and Pacific Northwest National Laboratory (PNNL). Test results show that the fatigue life is proportional to quality levels of machined edges or inversely proportional to the surface roughness Ra . Even at highest quality level, the average fatigue life of AWJ-machined parts is about 30% shorter than those of conventionally machined counterparts. Between two secondary processes, dry-grit blasting with aluminum oxide abrasives until the striation is removed visually yields excellent result. It actually prolongs the fatigue life of parts at least three times higher than that achievable with conventional machining. Dry-grit blasting is relatively simple and inexpensive to administrate and, equally important, alleviates the concerns of garnet embedment.

  14. Application of support vector machines to breast cancer screening using mammogram and clinical history data

    NASA Astrophysics Data System (ADS)

    Land, Walker H., Jr.; McKee, Dan; Velazquez, Roberto; Wong, Lut; Lo, Joseph Y.; Anderson, Francis R.

    2003-05-01

    The objectives of this paper are to discuss: (1) the development and testing of a new Evolutionary Programming (EP) method to optimally configure Support Vector Machine (SVM) parameters for facilitating the diagnosis of breast cancer; (2) evaluation of EP derived learning machines when the number of BI-RADS and clinical history discriminators are reduced from 16 to 7; (3) establishing system performance for several SVM kernels in addition to the EP/Adaptive Boosting (EP/AB) hybrid using the Digital Database for Screening Mammography, University of South Florida (DDSM USF) and Duke data sets; and (4) obtaining a preliminary evaluation of the measurement of SVM learning machine inter-institutional generalization capability using BI-RADS data. Measuring performance of the SVM designs and EP/AB hybrid against these objectives will provide quantative evidence that the software packages described can generalize to larger patient data sets from different institutions. Most iterative methods currently in use to optimize learning machine parameters are time consuming processes, which sometimes yield sub-optimal values resulting in performance degradation. SVMs are new machine intelligence paradigms, which use the Structural Risk Minimization (SRM) concept to develop learning machines. These learning machines can always be trained to provide global minima, given that the machine parameters are optimally computed. In addition, several system performance studies are described which include EP derived SVM performance as a function of: (a) population and generation size as well as a method for generating initial populations and (b) iteratively derived versus EP derived learning machine parameters. Finally, the authors describe a set of experiments providing preliminary evidence that both the EP/AB hybrid and SVM Computer Aided Diagnostic C++ software packages will work across a large population of patients, based on a data set of approximately 2,500 samples from five different

  15. Further application and amelioration of a novel CNC aspheric grinding machine

    NASA Astrophysics Data System (ADS)

    Hu, Jianjun; Pan, Junhua

    2006-02-01

    Aspheric surface can be thought as being enveloped by a series of spherical surfaces with their centre on the same axis but having different positions. These spherical surfaces are tangent with the aspheric surface. A Φ600 CNC aspheric grinding machine with this novel operating principleis manufactured. The machine was reported in August 2005. We choose δ p, ɛ and α p as the key parameters of our grinding machine. δ p is the distance between the cup shaped tool's bottom and the vertex of the aspheric surface. α p is the rotational angle of the cup shaped tool. ɛ is the space angle of the cup shaped tool during the fabrication process of convex aspheric surface. This grinding machine can be used to fabricate a conic concave aspheric surface continuously about three hours. But we need change the cup shaped tool one time when we fabricate a conic convex aspheric surface in also about three hours. The grinding machine can also be used to fabricate high-order aspheric surface. In the last report we intoroduced that we used this machined fabricating a RC telescope system's primary and the secondary mirror. The PV-value is less than 5μm for the primary Φ350 concave hyperbolic aspheric surface which departure is about 55μm. The residual errors can be removed easily. This machine have been improved both the cup shaped tool and filter system. Using this grinding machine we have fabricated another Φ460 concave aspheric surface during the last month. The PV-values of these two mirrors are both less than 7μm. The aspheric grinding machine can be fitted for fabricating concave conicoids.

  16. A demonstration of high precision GPS orbit determination for geodetic applications

    NASA Technical Reports Server (NTRS)

    Lichten, S. M.; Border, J. S.

    1987-01-01

    High precision orbit determination of Global Positioning System (GPS) satellites is a key requirement for GPS-based precise geodetic measurements and precise low-earth orbiter tracking, currently under study at JPL. Different strategies for orbit determination have been explored at JPL with data from a 1985 GPS field experiment. The most successful strategy uses multi-day arcs for orbit determination and includes fine tuning of spacecraft solar pressure coefficients and station zenith tropospheric delays using the GPS data. Average rms orbit repeatability values for 5 of the GPS satellites are 1.0, 1.2, and 1.7 m in altitude, cross-track, and down-track componenets when two independent 5-day fits are compared. Orbit predictions up to 24 hours outside the multi-day arcs agree within 4 m of independent solutions obtained with well tracked satellites in the prediction interval. Baseline repeatability improves with multi-day as compared to single-day arc orbit solutions. When tropospheric delay fluctuations are modeled with process noise, significant additional improvement in baseline repeatability is achieved. For a 246-km baseline, with 6-day arc solutions for GPS orbits, baseline repeatability is 2 parts in 100 million (0.4-0.6 cm) for east, north, and length components and 8 parts in 100 million for the vertical component. For 1314 and 1509 km baselines with the same orbits, baseline repeatability is 2 parts in 100 million for the north components (2-3 cm) and 4 parts in 100 million or better for east, length, and vertical components.

  17. A novel approach for high precision rapid potentiometric titrations: application to hydrazine assay.

    PubMed

    Sahoo, P; Malathi, N; Ananthanarayanan, R; Praveen, K; Murali, N

    2011-11-01

    We propose a high precision rapid personal computer (PC) based potentiometric titration technique using a specially designed mini-cell to carry out redox titrations for assay of chemicals in quality control laboratories attached to industrial, R&D, and nuclear establishments. Using this technique a few microlitre of sample (50-100 μl) in a total volume of ~2 ml solution can be titrated and the waste generated after titration is extremely low comparing to that obtained from the conventional titration technique. The entire titration including online data acquisition followed by immediate offline analysis of data to get information about concentration of unknown sample is completed within a couple of minutes (about 2 min). This facility has been created using a new class of sensors, viz., pulsating sensors developed in-house. The basic concept in designing such instrument and the salient features of the titration device are presented in this paper. The performance of the titration facility was examined by conducting some of the high resolution redox titrations using dilute solutions--hydrazine against KIO(3) in HCl medium, Fe(II) against Ce(IV) and uranium using Davies-Gray method. The precision of titrations using this innovative approach lies between 0.048% and 1.0% relative standard deviation in different redox titrations. With the evolution of this rapid PC based titrator it was possible to develop a simple but high precision potentiometric titration technique for quick determination of hydrazine in nuclear fuel dissolver solution in the context of reprocessing of spent nuclear fuel in fast breeder reactors.

  18. Precision bone and muscle loss measurements by advanced, multiple projection DEXA (AMPDXA) techniques for spaceflight applications

    NASA Technical Reports Server (NTRS)

    Charles, H. K. Jr; Beck, T. J.; Feldmesser, H. S.; Magee, T. C.; Spisz, T. S.; Pisacane, V. L.

    2001-01-01

    An advanced, multiple projection, dual energy x-ray absorptiometry (AMPDXA) scanner system is under development. The AMPDXA is designed to make precision bone and muscle loss measurements necessary to determine the deleterious effects of microgravity on astronauts as well as develop countermeasures to stem their bone and muscle loss. To date, a full size test system has been developed to verify principles and the results of computer simulations. Results indicate that accurate predictions of bone mechanical properties can be determined from as few as three projections, while more projections are needed for a complete, three-dimensional reconstruction. c 2001. Elsevier Science Ltd. All rights reserved.

  19. Polarisation control through an optical feedback technique and its application in precise measurements

    PubMed Central

    Chen, Wenxue; Zhang, Shulian; Long, Xingwu

    2013-01-01

    We present an anisotropic optical feedback technique for controlling light polarisation. The technique is based on the principle that the effective gain of a light mode is modulated by the magnitude of the anisotropic feedback. A new physical model that integrates Lamb's semi-classical theory and a model of the equivalent cavity of a Fabry-Perot interferometer is developed to reveal the physical nature of this technique. We use this technique to measure the phase retardation, optical axis, angle, thickness and refractive index with a high precision of λ/1380, 0.01°, 0.002°, 59 nm and 0.0006, respectively. PMID:23771164

  20. Improved treatment of global positioning system force parameters in precise orbit determination applications

    NASA Technical Reports Server (NTRS)

    Vigue, Y.; Lichten, S. M.; Muellerschoen, R. J.; Blewitt, G.; Heflin, M. B.

    1993-01-01

    Data collected from a worldwide 1992 experiment were processed at JPL to determine precise orbits for the satellites of the Global Positioning System (GPS). A filtering technique was tested to improve modeling of solar-radiation pressure force parameters for GPS satellites. The new approach improves orbit quality for eclipsing satellites by a factor of two, with typical results in the 25- to 50-cm range. The resultant GPS-based estimates for geocentric coordinates of the tracking sites, which include the three DSN sites, are accurate to 2 to 8 cm, roughly equivalent to 3 to 10 nrad of angular measure.

  1. Heaviside revisited: Distortionless signal transmission through lossy media with application to precision clock synchronization

    NASA Astrophysics Data System (ADS)

    Flake, Robert H.

    2016-02-01

    A recently discovered non-sinusoidal, non-periodic electrical signal in the form of an exponentially rising pulse achieves distortionless propagation at constant velocity through lossy, passive transmission media. This unique property is derived theoretically in the framework of the telegrapher's equation analyzed by Heaviside and confirmed experimentally in propagation of such a pulse along serially connected sections of telephone cable. The utility of the distortion-free pulse within the field of time-domain reflectometry is demonstrated in precise time-of-flight measurement of the reflected signal, with the prospect of enhancing the accuracy of protocols for synchronization of spatially separated clocks.

  2. A vector machine formulation with application to the computer-aided diagnosis of breast cancer from DCE-MRI screening examinations.

    PubMed

    Levman, Jacob E D; Warner, Ellen; Causer, Petrina; Martel, Anne L

    2014-02-01

    This study investigates the use of a proposed vector machine formulation with application to dynamic contrast-enhanced magnetic resonance imaging examinations in the context of the computer-aided diagnosis of breast cancer. This paper describes a method for generating feature measurements that characterize a lesion's vascular heterogeneity as well as a supervised learning formulation that represents an improvement over the conventional support vector machine in this application. Spatially varying signal-intensity measures were extracted from the examinations using principal components analysis and the machine learning technique known as the support vector machine (SVM) was used to classify the results. An alternative vector machine formulation was found to improve on the results produced by the established SVM in randomized bootstrap validation trials, yielding a receiver-operating characteristic curve area of 0.82 which represents a statistically significant improvement over the SVM technique in this application.

  3. New Freeform Manufacturing Chains Based on Atmospheric Plasma Jet Machining

    NASA Astrophysics Data System (ADS)

    Arnold, T.; Boehm, G.; Paetzelt, H.

    2016-01-01

    New manufacturing chains for precise fabrication of asphere and freeform optical surfaces including atmospheric Plasma Jet Machining (PJM) technology will be presented. PJM is based on deterministic plasma-assisted material removal. It has the potential for flexible and cost-efficient shape generation and correction of small and medium-sized optical freeform elements. The paper discusses the interactions between the plasma tools and optical fused silica samples in the context of the pre-machined and intermediate surface states and identifies several plasma jet machining methods for freeform generation, surface correction, and finishing as well as suitable auxiliary polishing methods. The successful application of either processing chain is demonstrated.

  4. Evaluation of the Terminal Precision Scheduling and Spacing System for Near-Term NAS Application

    NASA Technical Reports Server (NTRS)

    Thipphavong, Jane; Martin, Lynne Hazel; Swenson, Harry N.; Lin, Paul; Nguyen, Jimmy

    2012-01-01

    NASA has developed a capability for terminal area precision scheduling and spacing (TAPSS) to provide higher capacity and more efficiently manage arrivals during peak demand periods. This advanced technology is NASA's vision for the NextGen terminal metering capability. A set of human-in-the-loop experiments was conducted to evaluate the performance of the TAPSS system for near-term implementation. The experiments evaluated the TAPSS system under the current terminal routing infrastructure to validate operational feasibility. A second goal of the study was to measure the benefit of the Center and TRACON advisory tools to help prioritize the requirements for controller radar display enhancements. Simulation results indicate that using the TAPSS system provides benefits under current operations, supporting a 10% increase in airport throughput. Enhancements to Center decision support tools had limited impact on improving the efficiency of terminal operations, but did provide more fuel-efficient advisories to achieve scheduling conformance within 20 seconds. The TRACON controller decision support tools were found to provide the most benefit, by improving the precision in schedule conformance to within 20 seconds, reducing the number of arrivals having lateral path deviations by 50% and lowering subjective controller workload. Overall, the TAPSS system was found to successfully develop an achievable terminal arrival metering plan that was sustainable under heavy traffic demand levels and reduce the complexity of terminal operations when coupled with the use of the terminal controller advisory tools.

  5. Application of constrained-layer damping to a precision kinematic coupling

    SciTech Connect

    Jensen, S A; Hale, L C

    2000-10-10

    This paper addresses the need to support a very precise optical instrument while causing essentially no influence to its natural shape. Such influences could come from a number of sources, such as manufacturing tolerances, temperature changes, over-constrained structural members, or ground motion. Kinematic couplings have long been used for purposes of repeatable location and minimal influence to the supported object, however these couplings typically offer very little damping. This paper presents a kinematic coupling that utilizes constrained-layer damping techniques to damp out the first three modes of vibration of a precision optical instrument. Finite element analysis was used to aid in the design and tuning of the dampers for the kinematic coupling. Experimental tests were conducted and confirmed the effectiveness of the dampers. The quality factor (Q), which measure the amplification at resonance, dropped from 33.3 to 5.9 on the first mode, from 156.3 to 7.1 on the second mode, and from 147.1 to 18.5 on the third mode. These dampers help to ensure that the stringent vibration requirements necessary to produce high quality optical images are met.

  6. Machining of Aircraft Titanium with Abrasive-Waterjets for Fatigue Critical Applications

    SciTech Connect

    Liu, H. T.; Hovanski, Yuri; Dahl, Michael E.

    2012-02-01

    Laboratory tests were conducted to determine the fatigue performance of abrasive-waterjet- (AWJ-) machined aircraft titanium. Dog-bone specimens machined with AWJs were prepared and tested with and without sanding and dry-grit blasting with Al2O3 as secondary processes. The secondary processes were applied to remove the visual appearance of AWJ-generated striations and to clean up the garnet embedment. The fatigue performance of AWJ-machined specimens was compared with baseline specimens machined with CNC milling. Fatigue test results of the titanium specimens not only confirmed our previous findings in aluminum dog-bone specimens but in comparison also further enhanced the fatigue performance of the titanium. In addition, titanium is known to be difficult to cut, particularly for thick parts, however AWJs cut the material 34% faster han stainless steel. AWJ cutting and dry-grit blasting are shown to be a preferred ombination for processing aircraft titanium that is fatigue critical.

  7. Machining of Aircraft Titanium with Abrasive-Waterjets for Fatigue Critical Applications

    SciTech Connect

    Liu, H. T.; Hovanski, Yuri; Dahl, Michael E.

    2010-10-04

    Laboratory tests were conducted to determine the fatigue performance of AWJ-machined aircraft titanium. Dog-bone specimens machined with AWJs were prepared and tested with and without sanding and dry-grit blasting with Al2O3 as secondary processes. The secondary processes were applied to remove the visual appearance of AWJ-generated striations and to clean up the garnet embedment. The fatigue performance of AWJ-machined specimens was compared with baseline specimens machined with CNC milling. Fatigue test results not only confirmed the findings of the aluminum dog-bone specimens but also further enhance the fatigue performance. In addition, titanium is known to be notoriously difficult to cut with contact tools while AWJs cut it 34% faster than stainless steel. AWJ cutting and dry-grit blasting are shown to be a preferred combination for processing aircraft titanium that is fatigue critical.

  8. Machine and process characterization. Final report

    SciTech Connect

    Love, L.W.

    1992-12-01

    A study was conducted to statistically characterize 11 precision machining centers to determine their operating characteristics and process capabilities. Measurement probes and a ball plate were used for measurement analysis. A generic test part designed with geometric features that the department typically manufactures was machined using various machining processes. A better understanding of each machine`s characteristics and process capability was realized through repeating these methods on each machine.

  9. Application of differential evolution for optimization of least-square support vector machine classifier of signal-averaged electrocardiograms

    NASA Astrophysics Data System (ADS)

    Krys, Sebastian; Jankowski, Stanislaw; Piatkowska-Janko, Ewa

    2009-06-01

    This paper presents the application of differential evolution, an evolutionary algorithm of solving a single objective optimization problem - tuning the hiperparameters of least-square support vector machine classifier. The goal was to improve the classification of patients with sustained ventricular tachycardia after myocardial infarction based on a signal-averaged electrocardiography dataset received from the Medical University of Warsaw. The applied method attained a classification rate of 96% of the SVT+ group.

  10. Proceedings of the 12th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting

    NASA Technical Reports Server (NTRS)

    Wardrip, S. C. (Editor)

    1981-01-01

    The meeting gave PTTI managers, systems engineers, and program planners a transparent view of the state-of-the-art, an opportunity to express needs, a view of important future trends, and a review of relevant past accomplishments. The PTTI users were provided with new and useful applications, procedures, and techniques. Emphasis is placed on military applications and avionics.

  11. Development of a high precision dosimetry system for the measurement of surface dose rate distribution for eye applicators

    SciTech Connect

    Eichmann, Marion; Fluehs, Dirk; Spaan, Bernhard

    2009-10-15

    Purpose: The therapeutic outcome of the therapy with ophthalmic applicators is highly dependent on the application of a sufficient dose to the tumor, whereas the dose applied to the surrounding tissue needs to be minimized. The goal for the newly developed apparatus described in this work is the determination of the individual applicator surface dose rate distribution with a high spatial resolution and a high precision in dose rate with respect to time and budget constraints especially important for clinical procedures. Inhomogeneities of the dose rate distribution can be detected and taken into consideration for the treatment planning. Methods: In order to achieve this, a dose rate profile as well as a surface profile of the applicator are measured and correlated with each other. An instrumental setup has been developed consisting of a plastic scintillator detector system and a newly designed apparatus for guiding the detector across the applicator surface at a constant small distance. It performs an angular movement of detector and applicator with high precision. Results: The measurements of surface dose rate distributions discussed in this work demonstrate the successful operation of the measuring setup. Measuring the surface dose rate distribution with a small distance between applicator and detector and with a high density of measuring points results in a complete and gapless coverage of the applicator surface, being capable of distinguishing small sized spots with high activities. The dosimetrical accuracy of the measurements and its analysis is sufficient (uncertainty in the dose rate in terms of absorbed dose to water is <7%), especially when taking the surgical techniques in positioning of the applicator on the eyeball into account. Conclusions: The method developed so far allows a fully automated quality assurance of eye applicators even under clinical conditions. These measurements provide the basis for future calculation of a full 3D dose rate

  12. A model of application system for man-machine-environment system engineering in vessels based on IDEF0

    NASA Astrophysics Data System (ADS)

    Shang, Zhen; Qiu, Changhua; Zhu, Shifan

    2011-09-01

    Applying man-machine-environment system engineering (MMESE) in vessels is a method to improve the effectiveness of the interaction between equipment, environment, and humans for the purpose of advancing operating efficiency, performance, safety, and habitability of a vessel and its subsystems. In the following research, the life cycle of vessels was divided into 9 phases, and 15 research subjects were also identified from among these phases. The 15 subjects were systemized, and then the man-machine-environment engineering system application model for vessels was developed using the ICAM definition method 0 (IDEF0), which is a systematical modeling method. This system model bridges the gap between the data and information flow of every two associated subjects with the major basic research methods and approaches included, which brings the formerly relatively independent subjects together as a whole. The application of this systematic model should facilitate the application of man-machine-environment system engineering in vessels, especially at the conceptual and embodiment design phases. The managers and designers can deal with detailed tasks quickly and efficiently while reducing repetitive work.

  13. Design of a dual-axis optoelectronic level for precision angle measurements

    NASA Astrophysics Data System (ADS)

    Fan, Kuang-Chao; Wang, Tsung-Han; Lin, Sheng-Yi; Liu, Yen-Chih

    2011-05-01

    The accuracy of machine tools is mainly determined by angular errors during linear motion according to the well-known Abbe principle. Precision angle measurement is important to precision machines. This paper presents the theory and experiments of a new dual-axis optoelectronic level with low cost and high precision. The system adopts a commercial DVD pickup head as the angle sensor in association with the double-layer pendulum mechanism for two-axis swings, respectively. In data processing with a microprocessor, the measured angles of both axes can be displayed on an LCD or exported to an external PC. Calibrated by a triple-beam laser angular interferometer, the error of the dual-axis optoelectronic level is better than ±0.7 arcsec in the measuring range of ±30 arcsec, and the settling time is within 0.5 s. Experiments show the applicability to the inspection of precision machines.

  14. Design theory of full face rock tunnel boring machine transition cutter edge angle and its application

    NASA Astrophysics Data System (ADS)

    Zhang, Zhaohuang; Meng, Liang; Sun, Fei

    2013-05-01

    At present, the inner cutters of a full face rock tunnel boring machine (TBM) and transition cutter edge angles are designed on the basis of indentation test or linear grooving test. The inner and outer edge angles of disc cutters are characterized as symmetric to each other with respect to the cutter edge plane. This design has some practical defects, such as severe eccentric wear and tipping, etc. In this paper, the current design theory of disc cutter edge angle is analyzed, and the characteristics of the rock-breaking movement of disc cutters are studied. The researching results show that the rotational motion of disc cutters with the cutter head gives rise to the difference between the interactions of inner rock and outer rock with the contact area of disc cutters, with shearing and extrusion on the inner rock and attrition on the outer rock. The wear of disc cutters at the contact area is unbalanced, among which the wear in the largest normal stress area is most apparent. Therefore, a three-dimensional model theory of rock breaking and an edge angle design theory of transition disc cutter are proposed to overcome the flaws of the currently used TBM cutter heads, such as short life span, camber wearing, tipping. And a corresponding equation is established. With reference to a specific construction case, the edge angle of the transition disc cutter has been designed based on the theory. The application of TBM in some practical project proves that the theory has obvious advantages in enhancing disc cutter life, decreasing replacement frequency, and making economic benefits. The proposed research provides a theoretical basis for the design of TBM three-dimensional disc cutters whose rock-breaking operation time can be effectively increased.

  15. Advanced application flight experiments precision attitude determination system. Volume 2: System tests

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The performance capability of each of two precision attitude determination systems (PADS), one using a strapdown star tracker, and the other using a single-axis gimbal star tracker was measured in the laboratory under simulated orbit conditions. The primary focus of the evaluation was on the contribution to the total system accuracy by the star trackers, and the effectiveness of the software algorithms in functioning with actual sensor signals. A brief description of PADS, the laboratory test configuration and the test facility, is given along with a discussion of the data handling and display, laboratory computer programs, PADS performance evaluation programs, and the strapdown and gimbal system tests. Results are presented and discussed.

  16. High-precision calibration of a Scanning-Probe Microscope (SPM) for manufacturing applications

    SciTech Connect

    Chernoff, D.A.; Lohr, J.D.; Hansen, D.; Lines, M.

    1996-12-31

    For ordinary SPM (Scanning Probe Microscope) work, accuracy of XYZ length measurements of about 5% is acceptable. This is accomplished by periodic calibration checks (and adjustments, if required). Measurement of critical dimensions such as feature width and spacing on integrated circuits of compact discs requires much higher accuracy. For example, the new DVD (digital video disc) standard calls for a mean track pitch of 740 nm with a maximum allowable jitter (range) of 30 nm. To achieve a range of 30 nm, the standard deviation should be 10 nm or less. According to the gage-maker`s rule, the measurement tool should be 4x more precise than the object being measured, so we need a standard deviation of 2.5 nm. This report describes the combined use of a new type of calibration standard and new software to meet these requirements.

  17. High-precision optomechanical lens system for space applications assembled by a local soldering technique

    NASA Astrophysics Data System (ADS)

    Pleguezuelo, Pol Ribes; Koechlin, Charlie; Hornaff, Marcel; Kamm, Andreas; Beckert, Erik; Fiault, Guillaume; Eberhardt, Ramona; Tünnermann, Andreas

    2016-06-01

    Soldering using metallic solder alloys is an alternative to adhesive bonding. Laser-based soldering processes are especially well suited for the joining of optical components made of fragile and brittle materials such as glass, ceramics, and optical crystals. This is due to a localized and minimized input of thermal energy. Solderjet bumping technology has been used to assemble a lens mount breadboard using specifications and requirements found for the optical beam expander for the European Space Agency EarthCare Mission. The silica lens and a titanium barrel have been designed and assembled with this technology in order to withstand the stringent mission demands of handling high mechanical and thermal loads without losing the optical performance. Finally, a high-precision optomechanical lens mount has been assembled with minimal localized stress (<1 MPa) showing outstanding performance in terms of wave-front error and beam depolarization ratio before and after environmental tests.

  18. LD-pumped solid-state lasers with improved frequency, spatial, and polarization characteristics for precise spectroscopic applications

    NASA Astrophysics Data System (ADS)

    Drakov, A. S.; Kostik, O. E.; Mashko, V. V.; Teplyashin, L. L.; Bogdanovich, M. V.; Enzhyieuski, A. I.; Pozhidaev, A. V.; Ryabtsev, A. G.; Ryabtsev, G. I.; Shchemelev, M. A.

    2007-06-01

    New methods for precise control of main parameters of LD-pumped solid-state lasers assigned for spectroscopic applications have been developed. Tunable lasing in wide range has been achieved. Active elements on the base of crystals (Nd 3+:YAG, Nd 3+:YVO 4) and glasses (Er,Yb doped boro-silico-phosphate glass) were used. The active crystals with uniform and non-uniform distribution of the activator ions were studied. Output beams with high quality and polarization degree have been realized.

  19. Using kinematic reduction for studying grasping postures. An application to power and precision grasp of cylinders.

    PubMed

    Jarque-Bou, N; Gracia-Ibáñez, V; Sancho-Bru, J L; Vergara, M; Pérez-González, A; Andrés, F J

    2016-09-01

    The kinematic analysis of human grasping is challenging because of the high number of degrees of freedom involved. The use of principal component and factorial analyses is proposed in the present study to reduce the hand kinematics dimensionality in the analysis of posture for ergonomic purposes, allowing for a comprehensive study without losing accuracy while also enabling velocity and acceleration analyses to be performed. A laboratory study was designed to analyse the effect of weight and diameter in the grasping posture for cylinders. This study measured the hand posture from six subjects when transporting cylinders of different weights and diameters with precision and power grasps. The hand posture was measured using a Vicon(®) motion-tracking system, and the principal component analysis was applied to reduce the kinematics dimensionality. Different ANOVAs were performed on the reduced kinematic variables to check the effect of weight and diameter of the cylinders, as well as that of the subject. The results show that the original twenty-three degrees of freedom of the hand were reduced to five, which were identified as digit arching, closeness, palmar arching, finger adduction and thumb opposition. Both cylinder diameter and weight significantly affected the precision grasping posture: diameter affects closeness, palmar arching and opposition, while weight affects digit arching, palmar arching and closeness. The power-grasping posture was mainly affected by the cylinder diameter, through digit arching, closeness and opposition. The grasping posture was largely affected by the subject factor and this effect couldn't be attributed only to hand size. In conclusion, this kinematic reduction allowed identifying the effect of the diameter and weight of the cylinders in a comprehensive way, being diameter more important than weight.

  20. Using kinematic reduction for studying grasping postures. An application to power and precision grasp of cylinders.

    PubMed

    Jarque-Bou, N; Gracia-Ibáñez, V; Sancho-Bru, J L; Vergara, M; Pérez-González, A; Andrés, F J

    2016-09-01

    The kinematic analysis of human grasping is challenging because of the high number of degrees of freedom involved. The use of principal component and factorial analyses is proposed in the present study to reduce the hand kinematics dimensionality in the analysis of posture for ergonomic purposes, allowing for a comprehensive study without losing accuracy while also enabling velocity and acceleration analyses to be performed. A laboratory study was designed to analyse the effect of weight and diameter in the grasping posture for cylinders. This study measured the hand posture from six subjects when transporting cylinders of different weights and diameters with precision and power grasps. The hand posture was measured using a Vicon(®) motion-tracking system, and the principal component analysis was applied to reduce the kinematics dimensionality. Different ANOVAs were performed on the reduced kinematic variables to check the effect of weight and diameter of the cylinders, as well as that of the subject. The results show that the original twenty-three degrees of freedom of the hand were reduced to five, which were identified as digit arching, closeness, palmar arching, finger adduction and thumb opposition. Both cylinder diameter and weight significantly affected the precision grasping posture: diameter affects closeness, palmar arching and opposition, while weight affects digit arching, palmar arching and closeness. The power-grasping posture was mainly affected by the cylinder diameter, through digit arching, closeness and opposition. The grasping posture was largely affected by the subject factor and this effect couldn't be attributed only to hand size. In conclusion, this kinematic reduction allowed identifying the effect of the diameter and weight of the cylinders in a comprehensive way, being diameter more important than weight. PMID:27184310

  1. Alignment of Short Reads: A Crucial Step for Application of Next-Generation Sequencing Data in Precision Medicine.

    PubMed

    Ye, Hao; Meehan, Joe; Tong, Weida; Hong, Huixiao

    2015-01-01

    Precision medicine or personalized medicine has been proposed as a modernized and promising medical strategy. Genetic variants of patients are the key information for implementation of precision medicine. Next-generation sequencing (NGS) is an emerging technology for deciphering genetic variants. Alignment of raw reads to a reference genome is one of the key steps in NGS data analysis. Many algorithms have been developed for alignment of short read sequences since 2008. Users have to make a decision on which alignment algorithm to use in their studies. Selection of the right alignment algorithm determines not only the alignment algorithm but also the set of suitable parameters to be used by the algorithm. Understanding these algorithms helps in selecting the appropriate alignment algorithm for different applications in precision medicine. Here, we review current available algorithms and their major strategies such as seed-and-extend and q-gram filter. We also discuss the challenges in current alignment algorithms, including alignment in multiple repeated regions, long reads alignment and alignment facilitated with known genetic variants.

  2. Alignment of Short Reads: A Crucial Step for Application of Next-Generation Sequencing Data in Precision Medicine

    PubMed Central

    Ye, Hao; Meehan, Joe; Tong, Weida; Hong, Huixiao

    2015-01-01

    Precision medicine or personalized medicine has been proposed as a modernized and promising medical strategy. Genetic variants of patients are the key information for implementation of precision medicine. Next-generation sequencing (NGS) is an emerging technology for deciphering genetic variants. Alignment of raw reads to a reference genome is one of the key steps in NGS data analysis. Many algorithms have been developed for alignment of short read sequences since 2008. Users have to make a decision on which alignment algorithm to use in their studies. Selection of the right alignment algorithm determines not only the alignment algorithm but also the set of suitable parameters to be used by the algorithm. Understanding these algorithms helps in selecting the appropriate alignment algorithm for different applications in precision medicine. Here, we review current available algorithms and their major strategies such as seed-and-extend and q-gram filter. We also discuss the challenges in current alignment algorithms, including alignment in multiple repeated regions, long reads alignment and alignment facilitated with known genetic variants. PMID:26610555

  3. High precision delta(17)O isotope measurements of oxygen from silicates and other oxides: method and applications.

    PubMed

    Miller; Franchi; Sexton; Pillinger

    1999-07-01

    The use of infrared laser-assisted fluorination to release oxygen from milligram quantities of silicates or other oxide mineral grains is a well-established technique. However, relatively few studies have reported the optimisation of this procedure for oxygen-17 isotope measurements. We describe here details of an analytical system using infrared (10 µm) laser-assisted fluorination, in conjunction with a dual inlet mass spectrometer of high resolving power ( approximately 250) to provide (17)O and (18)O oxygen isotope measurements from 0.5-2 mg of silicates or other oxide mineral grains. Respective precisions (1) of typically 0.08 and 0.04 per thousand are obtained for the complete analytical procedure. Departures from the mass-dependent oxygen isotope fractionation line are quantified by Delta(17)O; our precision (1) of such measurements on individual samples is shown to be +/-0.024 per thousand. In turn, this permits the offset between parallel, mass-dependent fractionation lines to be characterised to substantially greater precision than has been possible hitherto. Application of this system to investigate the (17)O versus (18)O relationship for numerous terrestrial whole-rock and mineral samples, of diverse geological origins and age, indicates that the complete data set may be described by a single, mass-dependent fractionation line of slope 0.5244+/- 0.00038 (standard error). Copyright 1999 John Wiley & Sons, Ltd.

  4. Proceedings of the 14th Annual Precise Time and Time Interval (PTTI) Applications Planning Meeting

    NASA Technical Reports Server (NTRS)

    Wardrip, S. C. (Editor)

    1983-01-01

    Developments and applications in the field of frequency and time are addressed. Specific topics include rubidium frequency standards, future timing requirements, noise and atomic standards, hydrogen maser technology, synchronization, and quartz technology.

  5. Precise control and animation creation over the DMD for projection-based applications

    NASA Astrophysics Data System (ADS)

    Koudsi, Badia

    2014-03-01

    Digital micromirror devices (DMDs) are used in a variety of display and projection applications to produce high resolution images, both static and animated. A common obstacle to working with DMDs in research and development applications is the steep learning curve required to obtain proficiency in programming the boards that control the behavior of the DMDs. This can discourage developers who wish to use DMDs in new or novel research and development applications which might benefit from their light-control properties. A new software package called Light Animator has been developed that provides a user friendly and more intuitive interface for controlling the DMD. The software allows users to address the micromirror array by the drawing and animation of objects in a style similar to that of commercial drawing programs. Sequences and animation are controlled by dividing the sequence into frames which the user can draw individually or the software can fill in for the user. Examples and descriptions of the software operation are described and operational performance measures are provided. Potential applications include 3D volumetric displays, a 3D scanner when combining the DMD with a CCD camera, and most any 2D application for which DMDs are currently used. The software's capabilities allow scientists to develop applications more easily and effectively.

  6. True RGB line-scan camera for color machine vision applications

    NASA Astrophysics Data System (ADS)

    Lemstrom, Guy F.

    1994-10-01

    The design and technical capabilities of a true RGB 3 CCD chip color line scan camera are presented within this paper. The camera was developed for accurate color monitoring and analysis in industrial applications. A black & white line scan camera has been designed and built utilizing the same modular architecture of the color line scan camera. Color separation is made possible with a tri-chromatic RGB beam splitter. Three CCD linear arrays are precisely mounted to the output surfaces of the prism and the outputs of each CCD are exactly matched pixel by pixel. The beam splitter prism can be tailored to separate other spectral components than the standard RGB. A typical CCD can detect between 200 and 100 nm. Either two or three spectral regions can be separated using a beam splitter prism. The camera is totally digital and has a 16-bit parallel computer interface to communicate with a signal processing board. Because of the open architecture of the camera it's possible for the customer to design a board with some special functions handling the preprocessing of the data (for example RGB - HSI conversion). The camera can also be equipped with a high speed CPU-board with enough of local memory to do some image processing inside the camera before sending the data forward. The camera has been used in real industrial applications and has proven that its high resolution and high dynamic range can be used to measure minute color differences, enabling the separation or grading of objects such as minerals, food or other materials that could not otherwise be measured with a black and white camera.

  7. Application of Geo-Spatial Techniques for Precise Demarcation of Village/Panchayat Boundaries

    NASA Astrophysics Data System (ADS)

    Rao, S. S.; Banu, V.; Tiwari, A.; Bahuguna, S.; Uniyal, S.; Chavan, S. B.; Murthy, M. V. R.; Arya, V. S.; Nagaraja, R.; Sharma, J. R.

    2014-11-01

    In order to achieve the overall progress of the country with active and effective participation of all sections of society, the 12th Five Year Plan (FYP) would bring Panchayats centre-stage and achieve the inclusive growth agenda through inclusive governance. The concept of 'democratic decentralization' in the form of a three-tier administration was introduced in the name of "Panchayat Raj". Horizontally, it is a network of village Panchayats. Vertically, it is an organic growth of Panchayats rising up to national level. The Ministry of Panchayati Raj has three broad agenda: Empowerment, Enablement and Accountability. Space based Information Support for Decentralized Planning (SIS-DP) is one of the initiatives taken by Govt. of India with ISRO/DOS for generation and dissemination of spatial information for planning at the grass root level. The boundary layer for villages across different states/district/block is available with line departments. Most of these data exist at a much generalized scale. These boundaries do not overlay exactly with that of ground realities and may not be suitable for accurate analysis in terms of area, shape, position, etc. To deal with this problem, a strategy is adopted, which makes use of High Resolution Satellite Imagery (HRSI) from Indian Remote sensing satellites and cadastral maps at 1:4000 scale integrated with GIS techniques to enhance the accuracy of geo-spatial depiction of Village/Panchayat boundaries. Cadastral maps are used to depict the boundaries of land parcels and other features at the village level. These maps are registered to ortho products of HRSI using Ground Control Points. The cadastral maps are precisely overlaid on ortho-rectified HRSI and each parcel vertex is tagged with the real-world geographical coordinates. Village boundaries are extracted from the geo-referenced village cadastral maps. These boundaries are fine-tuned by considering under lap and overlap of neighboring villages and a mosaic is generated at

  8. Machinability Evaluation of Ti-5Nb- xFe Alloys for Dental Applications

    NASA Astrophysics Data System (ADS)

    Hsu, Hsueh-Chuan; Wu, Shih-Ching; Hsu, Shih-Kuang; Hsu, Kuan-Huang; Ho, Wen-Fu

    2015-03-01

    In this study, we evaluated the machinability of a series of Ti-5Nb- xFe alloys with an Fe content ranging from 1 to 5 mass% and compared the results to those of commercially pure titanium (c.p. Ti) and Ti-6Al-4V. The alloys were slotted using a milling machine and end mills under four cutting conditions. Machinability was evaluated using cutting force which was measured using a dynamometer. The experimental results indicate that the addition of Fe significantly affected the machinability of the Ti alloys in terms of cutting force under the present cutting conditions. Under certain conditions, the cutting force of Ti-5Nb-4Fe was lower than that of c.p. Ti and Ti-6Al-4V, a result which can be explained by a higher degree of hardness and greater amounts of ω phase. Ti-5Nb-4Fe also had a better surface finish: cutting marks were less apparent and metal chips did not adhere to the cut surfaces under cutting condition C (cutting speed: 1.83 m/s, feed rate: 0.0005 m/s, and depth of cut: 0.0002 m). Ti-5Nb-4Fe had the lowest average surface roughness ( R a) after machining (approximately 0.27 μm under cutting condition C).

  9. Prosthetic EMG control enhancement through the application of man-machine principles

    NASA Technical Reports Server (NTRS)

    Simcox, W. A.

    1977-01-01

    An area in medicine that appears suitable to man-machine principles is rehabilitation research, particularly when the motor aspects of the body are involved. If one considers the limb, whether functional or not, as the machine, the brain as the controller and the neuromuscular system as the man-machine interface, the human body is reduced to a man-machine system that can benefit from the principles behind such systems. The area of rehabilitation that this paper deals with is that of an arm amputee and his prosthetic device. Reducing this area to its man-machine basics, the problem becomes one of attaining natural multiaxis prosthetic control using Electromyographic activity (EMG) as the means of communication between man and prothesis. In order to use EMG as the communication channel it must be amplified and processed to yield a high information signal suitable for control. The most common processing scheme employed is termed Mean Value Processing. This technique for extracting the useful EMG signal consists of a differential to single ended conversion to the surface activity followed by a rectification and smoothing.

  10. A novel claw pole memory machine for wide-speed-range applications

    NASA Astrophysics Data System (ADS)

    Jian, Linni; Gong, Yu; Wei, Jin; Shi, Yujun; Shao, Ziyun; Ching, T. W.

    2015-05-01

    Memory machines with both high-power-density and wide-speed-range are becoming very attractive most recently. The purpose of this paper is to propose a novel type of memory machine, namely, claw pole memory machine. It engages an axially magnetized AlNiCo PM ring on the claw pole rotor to build the main magnetic flux in air-gap which is responsible for the electromechanical energy conversion. A magnetizing coil is equipped to online regulate the magnetization level of the permanent magnet ring, so as to achieve wide-speed-range operation. The operating principle is analyzed. The Preisach hysteresis model is combined with 3D finite element method to conduct performance assessment of the proposed claw pole memory machine. Calculation results demonstrate that the air-gap flux density can be readily adjusted by injecting DC pulse into the magnetizing coil, and the speed-range of the proposed machine can be extended as wide as six times of its base speed.

  11. Evaluation of a Metric Camera System Tailored for High Precision Uav Applications

    NASA Astrophysics Data System (ADS)

    Kraft, T.; Geßner, M.; Meißner, H.; Cramer, M.; Gerke, M.; Przybilla, H. J.

    2016-06-01

    In this paper we present the further evaluation of DLR's modular airborne camera system MACS-Micro for small unmanned aerial vehicle (UAV). The main focus is on standardized calibration procedures and on photogrammetric workflows. The current prototype consists of an industrial grade frame imaging camera with 12 megapixel resolutions and a compact GNSS/IMU solution which are operated by an embedded computing unit (CPU). The camera was calibrated once pre-flight and several times post-flight over a period of 5 month using a three dimensional test field. The verification of the radiometric quality of the acquired images has been done under controlled static conditions and kinematic conditions testing different demosaicing methods. The validation of MACS-Micro is done by comparing a traditional photogrammetric evaluation with the workflows of Agisoft Photoscan and Pix4D Mapper. The analyses are based on an aerial survey of an urban environment using precise ground control points and acquired GNSS observations. Aerial triangulations with different configuratrions of ground control points (GCP's) had been calculated, comparing the results of using a camera self-calibration and introducing fixed interior orientation parameters for Agisoft and Pix4D. The results are promising concerning the metric characteristics of the used camera and achieved accuracies in this test case. Further aspects have to be evaluated by further expanded test scenarios.

  12. THE APPLICATION OF MULTIVIEW METHODS FOR HIGH-PRECISION ASTROMETRIC SPACE VLBI AT LOW FREQUENCIES

    SciTech Connect

    Dodson, R.; Rioja, M.; Imai, H.; Asaki, Y.; Hong, X.-Y.; Shen, Z.

    2013-06-15

    High-precision astrometric space very long baseline interferometry (S-VLBI) at the low end of the conventional frequency range, i.e., 20 cm, is a requirement for a number of high-priority science goals. These are headlined by obtaining trigonometric parallax distances to pulsars in pulsar-black hole pairs and OH masers anywhere in the Milky Way and the Magellanic Clouds. We propose a solution for the most difficult technical problems in S-VLBI by the MultiView approach where multiple sources, separated by several degrees on the sky, are observed simultaneously. We simulated a number of challenging S-VLBI configurations, with orbit errors up to 8 m in size and with ionospheric atmospheres consistent with poor conditions. In these simulations we performed MultiView analysis to achieve the required science goals. This approach removes the need for beam switching requiring a Control Moment Gyro, and the space and ground infrastructure required for high-quality orbit reconstruction of a space-based radio telescope. This will dramatically reduce the complexity of S-VLBI missions which implement the phase-referencing technique.

  13. Delivery and application of precise timing for a traveling wave powerline fault locator system

    NASA Technical Reports Server (NTRS)

    Street, Michael A.

    1990-01-01

    The Bonneville Power Administration (BPA) has successfully operated an in-house developed powerline fault locator system since 1986. The BPA fault locator system consists of remotes installed at cardinal power transmission line system nodes and a central master which polls the remotes for traveling wave time-of-arrival data. A power line fault produces a fast rise-time traveling wave which emanates from the fault point and propagates throughout the power grid. The remotes time-tag the traveling wave leading edge as it passes through the power system cardinal substation nodes. A synchronizing pulse transmitted via the BPA analog microwave system on a wideband channel sychronizes the time-tagging counters in the remote units to a different accuracy of better than one microsecond. The remote units correct the raw time tags for synchronizing pulse propagation delay and return these corrected values to the fault locator master. The master then calculates the power system disturbance source using the collected time tags. The system design objective is a fault location accuracy of 300 meters. BPA's fault locator system operation, error producing phenomena, and method of distributing precise timing are described.

  14. Cross-platform normalization of microarray and RNA-seq data for machine learning applications.

    PubMed

    Thompson, Jeffrey A; Tan, Jie; Greene, Casey S

    2016-01-01

    Large, publicly available gene expression datasets are often analyzed with the aid of machine learning algorithms. Although RNA-seq is increasingly the technology of choice, a wealth of expression data already exist in the form of microarray data. If machine learning models built from legacy data can be applied to RNA-seq data, larger, more diverse training datasets can be created and validation can be performed on newly generated data. We developed Training Distribution Matching (TDM), which transforms RNA-seq data for use with models constructed from legacy platforms. We evaluated TDM, as well as quantile normalization, nonparanormal transformation, and a simple log 2 transformation, on both simulated and biological datasets of gene expression. Our evaluation included both supervised and unsupervised machine learning approaches. We found that TDM exhibited consistently strong performance across settings and that quantile normalization also performed well in many circumstances. We also provide a TDM package for the R programming language. PMID:26844019

  15. Cross-platform normalization of microarray and RNA-seq data for machine learning applications.

    PubMed

    Thompson, Jeffrey A; Tan, Jie; Greene, Casey S

    2016-01-01

    Large, publicly available gene expression datasets are often analyzed with the aid of machine learning algorithms. Although RNA-seq is increasingly the technology of choice, a wealth of expression data already exist in the form of microarray data. If machine learning models built from legacy data can be applied to RNA-seq data, larger, more diverse training datasets can be created and validation can be performed on newly generated data. We developed Training Distribution Matching (TDM), which transforms RNA-seq data for use with models constructed from legacy platforms. We evaluated TDM, as well as quantile normalization, nonparanormal transformation, and a simple log 2 transformation, on both simulated and biological datasets of gene expression. Our evaluation included both supervised and unsupervised machine learning approaches. We found that TDM exhibited consistently strong performance across settings and that quantile normalization also performed well in many circumstances. We also provide a TDM package for the R programming language.

  16. Cross-platform normalization of microarray and RNA-seq data for machine learning applications

    PubMed Central

    Thompson, Jeffrey A.; Tan, Jie

    2016-01-01

    Large, publicly available gene expression datasets are often analyzed with the aid of machine learning algorithms. Although RNA-seq is increasingly the technology of choice, a wealth of expression data already exist in the form of microarray data. If machine learning models built from legacy data can be applied to RNA-seq data, larger, more diverse training datasets can be created and validation can be performed on newly generated data. We developed Training Distribution Matching (TDM), which transforms RNA-seq data for use with models constructed from legacy platforms. We evaluated TDM, as well as quantile normalization, nonparanormal transformation, and a simple log2 transformation, on both simulated and biological datasets of gene expression. Our evaluation included both supervised and unsupervised machine learning approaches. We found that TDM exhibited consistently strong performance across settings and that quantile normalization also performed well in many circumstances. We also provide a TDM package for the R programming language. PMID:26844019

  17. Precision manometer gauge

    DOEpatents

    McPherson, Malcolm J.; Bellman, Robert A.

    1984-01-01

    A precision manometer gauge which locates a zero height and a measured height of liquid using an open tube in communication with a reservoir adapted to receive the pressure to be measured. The open tube has a reference section carried on a positioning plate which is moved vertically with machine tool precision. Double scales are provided to read the height of the positioning plate accurately, the reference section being inclined for accurate meniscus adjustment, and means being provided to accurately locate a zero or reference position.

  18. Precision manometer gauge

    DOEpatents

    McPherson, M.J.; Bellman, R.A.

    1982-09-27

    A precision manometer gauge which locates a zero height and a measured height of liquid using an open tube in communication with a reservoir adapted to receive the pressure to be measured. The open tube has a reference section carried on a positioning plate which is moved vertically with machine tool precision. Double scales are provided to read the height of the positioning plate accurately, the reference section being inclined for accurate meniscus adjustment, and means being provided to accurately locate a zero or reference position.

  19. Scattering effects of machined optical surfaces

    NASA Astrophysics Data System (ADS)

    Thompson, Anita Kotha

    1998-09-01

    Optical fabrication is one of the most labor-intensive industries in existence. Lensmakers use pitch to affix glass blanks to metal chucks that hold the glass as they grind it with tools that have not changed much in fifty years. Recent demands placed on traditional optical fabrication processes in terms of surface accuracy, smoothnesses, and cost effectiveness has resulted in the exploitation of precision machining technology to develop a new generation of computer numerically controlled (CNC) optical fabrication equipment. This new kind of precision machining process is called deterministic microgrinding. The most conspicuous feature of optical surfaces manufactured by the precision machining processes (such as single-point diamond turning or deterministic microgrinding) is the presence of residual cutting tool marks. These residual tool marks exhibit a highly structured topography of periodic azimuthal or radial deterministic marks in addition to random microroughness. These distinct topographic features give rise to surface scattering effects that can significantly degrade optical performance. In this dissertation project we investigate the scattering behavior of machined optical surfaces and their imaging characteristics. In particular, we will characterize the residual optical fabrication errors and relate the resulting scattering behavior to the tool and machine parameters in order to evaluate and improve the deterministic microgrinding process. Other desired information derived from the investigation of scattering behavior is the optical fabrication tolerances necessary to satisfy specific image quality requirements. Optical fabrication tolerances are a major cost driver for any precision optical manufacturing technology. The derivation and control of the optical fabrication tolerances necessary for different applications and operating wavelength regimes will play a unique and central role in establishing deterministic microgrinding as a preferred and a

  20. Diamond machining of steel molds for optical components

    NASA Astrophysics Data System (ADS)

    Bohr, Roland

    2016-08-01

    The requirement of ultra precision diamond machining of lens molds in steel is identified. A solution for this type of machining is presented and results of such a machining in steel compared to standard milling and polishing process are shown.

  1. The Principle and Applications of Multi-Plane Separation for Balancing Machines

    NASA Astrophysics Data System (ADS)

    Kang, Y.; Sheen, G.-J.; Tang, P.-H.

    1997-11-01

    Two-plane separation is a conventional technique of balancing machines for rigid rotors such that each sensor measures the separated effects of equivalent imbalances in two planes. However, some complex rigid rotors such as multicylinder crankshafts need to be balanced by multi-plane correction for reducing mass concentration at two planes. This study verifies the principle of plane separation by using an exact-point influence coefficient approach. From the analysis a generalized algorithm of multiplane separation can be developed. Thus, an unlimited technique of plane separation is provided to improve balancing machines for complex rotors which have several planes in need of correction.

  2. High-Precision Selenium Isotope Analysis by Hydride Generation MC-ICP-MS: Environmental Applications

    NASA Astrophysics Data System (ADS)

    Schmidberger, S.; Simonetti, A.; Gariépy, C.

    2003-04-01

    The global cycle and the natural isotopic variation of Se in the lithosphere, biosphere, hydrosphere and atmosphere are currently little constrained. The study of Se isotope systematics by negative thermal ionization mass spectrometry (NTIMS) has documented large Se isotope variations up to 15 ppm in various natural samples (δ80Se/76Se; Johnson et al., 1999), indicating its important potential as a tracer in geological and biological processes. Recently, Se isotope measurements on sulfide deposits from hydrothermal systems were obtained using a Micromass IsoProbe multicollector inductively coupled plasma mass spectrometer coupled to a hydride generator (Rouxel et al. 2002). This technique allows for high-precision Se isotope analysis on small sample sizes (<= 100 ng), and thus is a prerequisite for precise Se isotope measurements in low abundance samples such as precipitations, freshwaters and atmospheric aerosols (1 ppb or less). We have developed a 74-82Se double spike technique, which corrects for instrumental mass fractionation during both isotopic analysis and chemical processing. During double spike calibration, mass discrimination was monitored using a Germanium Specpuretextregistered standard (25 ppb). The isotopic composition of the Ge standard was accurately determined using a 10 ppb solution of the isotopic Gallium standard SRM 994. Repeated measurements (n=8) of the Ge standard yielded an external reproducibility of 0.13 ppm and a 74Ge/72Ge ratio of 1.32987. Instrumental mass bias evaluated with the Ge standard was essentially invariant over a three-month period. Our results yield an external reproducibility of 0.4 ppm (80Se/76Se) for a 100 ppb solution of the Se standard SRM 3149 (˜100 ng of total Se consumed). This ongoing study focuses on determining the Se isotopic compositions of precipitations and aerosol samples from remote and urban areas in northeastern North America. The preliminary results for precipitation samples (˜100 to 300 ml of rain

  3. Opticam PM machine design

    NASA Astrophysics Data System (ADS)

    Liedes, Jyrki T.

    1992-12-01

    Rank Pneumo has worked with the Center for Optics Manufacturing and the Center's Manufacturing Advisory Board to design a multi-axis prism grinding machine. The Opticam PM is a three axis, high precision CNC reciprocating grinder. It is designed for the automated manufacturing of glass prisms. Unique features of the design incorporate electrolytic in- process dressing of the finishing wheel, nested grinding wheels and machine resident metrology to provide RQM (Real-time Quality Management).

  4. Precise and accurate assessment of uncertainties in model parameters from stellar interferometry. Application to stellar diameters

    NASA Astrophysics Data System (ADS)

    Lachaume, Regis; Rabus, Markus; Jordan, Andres

    2015-08-01

    In stellar interferometry, the assumption that the observables can be seen as Gaussian, independent variables is the norm. In particular, neither the optical interferometry FITS (OIFITS) format nor the most popular fitting software in the field, LITpro, offer means to specify a covariance matrix or non-Gaussian uncertainties. Interferometric observables are correlated by construct, though. Also, the calibration by an instrumental transfer function ensures that the resulting observables are not Gaussian, even if uncalibrated ones happened to be so.While analytic frameworks have been published in the past, they are cumbersome and there is no generic implementation available. We propose here a relatively simple way of dealing with correlated errors without the need to extend the OIFITS specification or making some Gaussian assumptions. By repeatedly picking at random which interferograms, which calibrator stars, and which are the errors on their diameters, and performing the data processing on the bootstrapped data, we derive a sampling of p(O), the multivariate probability density function (PDF) of the observables O. The results can be stored in a normal OIFITS file. Then, given a model m with parameters P predicting observables O = m(P), we can estimate the PDF of the model parameters f(P) = p(m(P)) by using a density estimation of the observables' PDF p.With observations repeated over different baselines, on nights several days apart, and with a significant set of calibrators systematic errors are de facto taken into account. We apply the technique to a precise and accurate assessment of stellar diameters obtained at the Very Large Telescope Interferometer with PIONIER.

  5. Strategies of ARP application (Automatic Resistivity Profiling) for viticultural precision farming

    NASA Astrophysics Data System (ADS)

    Costantini, E. A. C.; Andrenelli, M. C.; Bucelli, P.; Magini, S.; Natarelli, L.; Pellegrini, S.; Perria, R.; Storchi, P.; Vignozzi, N.

    2009-04-01

    Introduction Viticultural precision farming needs detailed soil information, which can be obtained by means of remote as well as proximal sensors, besides traditional invasive soil survey. Nevertheless, the use of the new technologies is still in its infancy, because of their costs and the lack of knowledge about the detail actually needed for the viticultural husbandry. The main aim of this work was to test the sensitivity of the ARP methodology (Automatic Resistivity Profiling) in supporting soil survey for viticultural precision farming. In addition, we tried to optimize the detail of geoelectrical measurements and soil sampling to reduce the cost of the integrated survey, maintaining a significant information accuracy for viticulture. Materials and methods Two vineyards in coastal Tuscany (central Italy), about 3.5 ha each, were selected. Vineyard 1 was cultivated with Cabernet Sauvignon and Cabernet Franc, while vineyard 2 only had Cabernet Sauvignon. Soil survey and geoelectrical investigation were conducted in may 2007. The ARP methodology consists in the injection in soil of electric current through one pair of electrodes mounted on teeth wheels and measuring the resulting potential with other three pairs of electrodes, placed of the same mobile equipment. The electrical resistance of the soil (ER) is expressed as ohm per m. The depth of investigation is a function of the geometry of the electrodes and the soil being probed. Increasing the distance between electrodes will increase the depth while decreasing the measured potential. The innovative character of the ARP technique is represented by the passage of a mobile machinery, able to perform 30,000 measurements per hectare, with a measurement every 0.2 m. The ARP system, equipped with a digital encoder and DGPS system, is transported by a four-wheeled vehicle. It is fitted with three sensors that contemporaneously analyse three distinct levels of the soil, the values of which are represented by maps of

  6. A Loader for Executing Multi-Binary Applications on the Thinking Machines CM-5: It's Not Just for SPMD Anymore

    NASA Technical Reports Server (NTRS)

    Becker, Jeffrey C.

    1995-01-01

    The Thinking Machines CM-5 platform was designed to run single program, multiple data (SPMD) applications, i.e., to run a single binary across all nodes of a partition, with each node possibly operating on different data. Certain classes of applications, such as multi-disciplinary computational fluid dynamics codes, are facilitated by the ability to have subsets of the partition nodes running different binaries. In order to extend the CM-5 system software to permit such applications, a multi-program loader was developed. This system is based on the dld loader which was originally developed for workstations. This paper provides a high level description of dld, and describes how it was ported to the CM-5 to provide support for multi-binary applications. Finally, it elaborates how the loader has been used to implement the CM-5 version of MPIRUN, a portable facility for running multi-disciplinary/multi-zonal MPI (Message-Passing Interface Standard) codes.

  7. Manufacturing process applications team (MATEAM). [technology transfer in the areas of machine tools and robots

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The transfer of NASA technology to the industrial sector is reported. Presentations to the machine tool and robot industries and direct technology transfers of the Adams Manipulator arm, a-c motor control, and the bolt tension monitor are discussed. A listing of proposed RTOP programs with strong potential is included. A detailed description of the rotor technology available to industry is given.

  8. Mathematics for the Workplace. Applications from Machine Tool Technology (Michelin Tire Corporation). A Teacher's Guide.

    ERIC Educational Resources Information Center

    Wallace, Johnny M.; Stewart, Grover

    This module presents a real-world context in which mathematics skills (geometry and trigonometry) are used as part of a daily routine. The context is the machine tool technology field, and the module aims to help students develop the ability to analyze diagrams in order to make mathematical computations. The modules, which features applications…

  9. Development of a sterilizing in-place application for a production machine using Vaporized Hydrogen Peroxide.

    PubMed

    Mau, T; Hartmann, V; Burmeister, J; Langguth, P; Häusler, H

    2004-01-01

    The use of steam in sterilization processes is limited by the implementation of heat-sensitive components inside the machines to be sterilized. Alternative low-temperature sterilization methods need to be found and their suitability evaluated. Vaporized Hydrogen Peroxide (VHP) technology was adapted for a production machine consisting of highly sensitive pressure sensors and thermo-labile air tube systems. This new kind of "cold" surface sterilization, known from the Barrier Isolator Technology, is based on the controlled release of hydrogen peroxide vapour into sealed enclosures. A mobile VHP generator was used to generate the hydrogen peroxide vapour. The unit was combined with the air conduction system of the production machine. Terminal vacuum pumps were installed to distribute the gas within the production machine and for its elimination. In order to control the sterilization process, different physical process monitors were incorporated. The validation of the process was based on biological indicators (Geobacillus stearothermophilus). The Limited Spearman Karber Method (LSKM) was used to statistically evaluate the sterilization process. The results show that it is possible to sterilize surfaces in a complex tube system with the use of gaseous hydrogen peroxide. A total microbial reduction of 6 log units was reached. PMID:15233253

  10. Elevating Virtual Machine Introspection for Fine-Grained Process Monitoring: Techniques and Applications

    ERIC Educational Resources Information Center

    Srinivasan, Deepa

    2013-01-01

    Recent rapid malware growth has exposed the limitations of traditional in-host malware-defense systems and motivated the development of secure virtualization-based solutions. By running vulnerable systems as virtual machines (VMs) and moving security software from inside VMs to the outside, the out-of-VM solutions securely isolate the anti-malware…

  11. A computer architecture for intelligent machines

    NASA Technical Reports Server (NTRS)

    Lefebvre, D. R.; Saridis, G. N.

    1991-01-01

    The Theory of Intelligent Machines proposes a hierarchical organization for the functions of an autonomous robot based on the Principle of Increasing Precision With Decreasing Intelligence. An analytic formulation of this theory using information-theoretic measures of uncertainty for each level of the intelligent machine has been developed in recent years. A computer architecture that implements the lower two levels of the intelligent machine is presented. The architecture supports an event-driven programming paradigm that is independent of the underlying computer architecture and operating system. Details of Execution Level controllers for motion and vision systems are addressed, as well as the Petri net transducer software used to implement Coordination Level functions. Extensions to UNIX and VxWorks operating systems which enable the development of a heterogeneous, distributed application are described. A case study illustrates how this computer architecture integrates real-time and higher-level control of manipulator and vision systems.

  12. On-the-fly Locata/inertial navigation system integration for precise maritime application

    NASA Astrophysics Data System (ADS)

    Jiang, Wei; Li, Yong; Rizos, Chris

    2013-10-01

    The application of Global Navigation Satellite System (GNSS) technology has meant that marine navigators have greater access to a more consistent and accurate positioning capability than ever before. However, GNSS may not be able to meet all emerging navigation performance requirements for maritime applications with respect to service robustness, accuracy, integrity and availability. In particular, applications in port areas (for example automated docking) and in constricted waterways, have very stringent performance requirements. Even when an integrated inertial navigation system (INS)/GNSS device is used there may still be performance gaps. GNSS signals are easily blocked or interfered with, and sometimes the satellite geometry may not be good enough for high accuracy and high reliability applications. Furthermore, the INS accuracy degrades rapidly during GNSS outages. This paper investigates the use of a portable ground-based positioning system, known as ‘Locata’, which was integrated with an INS, to provide accurate navigation in a marine environment without reliance on GNSS signals. An ‘on-the-fly’ Locata resolution algorithm that takes advantage of geometry change via an extended Kalman filter is proposed in this paper. Single-differenced Locata carrier phase measurements are utilized to achieve accurate and reliable solutions. A ‘loosely coupled’ decentralized Locata/INS integration architecture based on the Kalman filter is used for data processing. In order to evaluate the system performance, a field trial was conducted on Sydney Harbour. A Locata network consisting of eight Locata transmitters was set up near the Sydney Harbour Bridge. The experiment demonstrated that the Locata on-the-fly (OTF) algorithm is effective and can improve the system accuracy in comparison with the conventional ‘known point initialization’ (KPI) method. After the OTF and KPI comparison, the OTF Locata/INS integration is then assessed further and its performance

  13. Parallel Kinematic Machines (PKM)

    SciTech Connect

    Henry, R.S.

    2000-03-17

    The purpose of this 3-year cooperative research project was to develop a parallel kinematic machining (PKM) capability for complex parts that normally require expensive multiple setups on conventional orthogonal machine tools. This non-conventional, non-orthogonal machining approach is based on a 6-axis positioning system commonly referred to as a hexapod. Sandia National Laboratories/New Mexico (SNL/NM) was the lead site responsible for a multitude of projects that defined the machining parameters and detailed the metrology of the hexapod. The role of the Kansas City Plant (KCP) in this project was limited to evaluating the application of this unique technology to production applications.

  14. The precise measurement of the attenuation coefficients of various IR optical materials applicable to immersion grating

    NASA Astrophysics Data System (ADS)

    Kaji, Sayumi; Sarugaku, Yuki; Ikeda, Yuji; Kobayashi, Naoto; Nakanishi, Kenshi; Kondo, Sohei; Yasui, Chikako; Kawakita, Hideyo

    2014-07-01

    Immersion grating is a next-generation diffraction grating which has the immersed the diffraction surface in an optical material with high refractive index of n > 2, and can provide higher spectral resolution than a classical reflective grating. Our group is developing various immersion gratings from the near- to mid-infrared region (Ikeda et al.1, 2, 3, 4, Sarugaku et al.5, and Sukegawa et al.6). The internal attenuation αatt of the candidate materials is especially very important to achieve the high efficiency immersion gratings used for astronomical applications. Nevertheless, because there are few available data as αatt < 0.01cm-1 in the infrared region, except for measurements of CVD-ZnSe, CVD-ZnS, and single-crystal Si in the short near-infrared region reported by Ikeda et al.7, we cannot select suitable materials as an immersion grating in an aimed wavelength range. Therefore, we measure the attenuation coefficients of CdTe, CdZnTe, Ge, Si, ZnSe, and ZnS that could be applicable to immersion gratings. We used an originally developed optical unit attached to a commercial FTIR which covers the wide wavelength range from 1.3μm to 28μm. This measurement system achieves the high accuracy of (triangle)αatt ~ 0.01cm-1. As a result, high-resistivity single-crystal CdZnTe, single-crystal Ge, single-crystal Si, CVD-ZnSe, and CVD-ZnS show αatt < 0.01cm-1 at the wavelength range of 5.5 - 19.0μm, 2.0 - 10.5μm, 1.3 - 5.4μm, 1.7 - 13.2μm, and 1.9 - 9.2μm, respectively. This indicates that these materials are good candidates for high efficiency immersion grating covering those wavelength ranges. We plan to make similar measurement under the cryogenic condition as T <= 10K for the infrared, especially mid-infrared applications.

  15. Application of the nonlinear, double-dynamic Taguchi method to the precision positioning device using combined piezo-VCM actuator.

    PubMed

    Liu, Yung-Tien; Fung, Rong-Fong; Wang, Chun-Chao

    2007-02-01

    In this research, the nonlinear, double-dynamic Taguchi method was used as design and analysis methods for a high-precision positioning device using the combined piezo-voice-coil motor (VCM) actuator. An experimental investigation into the effects of two input signals and three control factors were carried out to determine the optimum parametric configuration of the positioning device. The double-dynamic Taguchi method, which permits optimization of several control factors concurrently, is particularly suitable for optimizing the performance of a positioning device with multiple actuators. In this study, matrix experiments were conducted with L9(3(4)) orthogonal arrays (OAs). The two most critical processes for the optimization of positioning device are the identification of the nonlinear ideal function and the combination of the double-dynamic signal factors for the ideal function's response. The driving voltage of the VCM and the waveform amplitude of the PZT actuator are combined into a single quality characteristic to evaluate the positioning response. The application of the double-dynamic Taguchi method, with dynamic signal-to-noise ratio (SNR) and L9(3(4)) OAs, reduced the number of necessary experiments. The analysis of variance (ANOVA) was applied to set the optimum parameters based on the high-precision positioning process.

  16. Precise and millidegree stable temperature control for fluorescence imaging: Application to phase transitions in lipid membranes

    PubMed Central

    Farkas, Elaine R.; Webb, Watt W.

    2010-01-01

    We present the design of a custom temperature-controlled chamber suitable for water or oil immersion fluorescence microscopy and its application to phase behavior in lipid bilayer vesicles. The apparatus is self-contained and portable, suitable for multiuser microscopy facilities. It offers a higher temperature resolution and stability than any comparable commercial apparatus, on the order of millidegrees. We demonstrate the utility of the system in the study of miscibility transitions in model membranes. The temperature-dependent phase behavior of model membrane systems that display liquid-ordered (Lo) phase coexistence with the liquid-disordered (Ld) phase is relevant to understanding the existence of heterogeneities in biological cell plasma membranes, ubiquitously termed “lipid rafts.” PMID:20886984

  17. In-situ and non-destructive focus determination device for high-precision laser applications

    NASA Astrophysics Data System (ADS)

    Armbruster, Oskar; Naghilou, Aida; Pöhl, Hannes; Kautek, Wolfgang

    2016-09-01

    A non-destructive, in-line, and low-cost focusing device based on an image sensor has been developed and demonstrated. It allows an in situ focus determination for a broad variety of laser types (e.g. cw and pulsed lasers). It provides stringent focusing conditions with high numerical apertures. This approach does not require sub-picosecond and/or auxiliary lasers, or high fluences above damage thresholds. Applications of this system include, but are not limited to the laser-illumination of micro-electrodes, pump-probe microscopy on thin films, and laser ablation of small samples without sufficient surface area for focus determination by ablation. An uncertainty of the focus position by an order of magnitude less than the respective Rayleigh length could be demonstrated.

  18. FIRESTORM: a collaborative network suite application for rapid sensor data processing and precise decisive responses

    NASA Astrophysics Data System (ADS)

    Kaniyantethu, Shaji

    2011-06-01

    This paper discusses the many features and composed technologies in Firestorm™ - a Distributed Collaborative Fires and Effects software. Modern response management systems capitalize on the capabilities of a plethora of sensors and its output for situational awareness. Firestorm utilizes a unique networked lethality approach by integrating unmanned air and ground vehicles to provide target handoff and sharing of data between humans and sensors. The system employs Bayesian networks for track management of sensor data, and distributed auction algorithms for allocating targets and delivering the right effect without information overload to the Warfighter. Firestorm Networked Effects Component provides joint weapon-target pairing, attack guidance, target selection standards, and other fires and effects components. Moreover, the open and modular architecture allows for easy integration with new data sources. Versatility and adaptability of the application enable it to devise and dispense a suitable response to a wide variety of scenarios. Recently, this application was used for detecting and countering a vehicle intruder with the help of radio frequency spotter sensor, command driven cameras, remote weapon system, portable vehicle arresting barrier, and an unmanned aerial vehicle - which confirmed the presence of the intruder, as well as provided lethal/non-lethal response and battle damage assessment. The completed demonstrations have proved Firestorm's™ validity and feasibility to predict, detect, neutralize, and protect key assets and/or area against a variety of possible threats. The sensors and responding assets can be deployed with numerous configurations to cover the various terrain and environmental conditions, and can be integrated to a number of platforms.

  19. Tattoo machines, needles and utilities.

    PubMed

    Rosenkilde, Frank

    2015-01-01

    Starting out as a professional tattooist back in 1977 in Copenhagen, Denmark, Frank Rosenkilde has personally experienced the remarkable development of tattoo machines, needles and utilities: all the way from home-made equipment to industrial products of substantially improved quality. Machines can be constructed like the traditional dual-coil and single-coil machines or can be e-coil, rotary and hybrid machines, with the more convenient and precise rotary machines being the recent trend. This development has resulted in disposable needles and utilities. Newer machines are more easily kept clean and protected with foil to prevent crosscontaminations and infections. The machines and the tattooists' knowledge and awareness about prevention of infection have developed hand-in-hand. For decades, Frank Rosenkilde has been collecting tattoo machines. Part of his collection is presented here, supplemented by his personal notes. PMID:25833620

  20. Precision Herbicide Application Technologies To Decrease Herbicide Losses in Furrow Irrigation Outflows in a Northeastern Australian Cropping System.

    PubMed

    Davis, Aaron M; Pradolin, Jordan

    2016-05-25

    This study compared water quality benefits of using precision herbicide application technologies in relation to traditional spraying approaches across several pre- and postemergent herbicides in furrow-irrigated canefarming systems. The use of shielded sprayers (herbicide banding) provided herbicide load reductions extending substantially beyond simple proportionate decreases in amount of active herbicide ingredient applied to paddocks. These reductions were due largely to the extra management control available to irrigating growers in relation to where both herbicides and irrigation water can be applied to paddocks, coupled with knowledge of herbicide toxicological and physicochemical properties. Despite more complex herbicide mixtures being applied in banded practices, banding provided capacity for greatly reduced environmental toxicity in off-paddock losses. Similar toxicological and loss profiles of alternative herbicides relative to recently regulated pre-emergent herbicides highlight the need for a carefully considered approach to integrating alternative herbicides into improved pest management. PMID:26795709

  1. Precision Herbicide Application Technologies To Decrease Herbicide Losses in Furrow Irrigation Outflows in a Northeastern Australian Cropping System.

    PubMed

    Davis, Aaron M; Pradolin, Jordan

    2016-05-25

    This study compared water quality benefits of using precision herbicide application technologies in relation to traditional spraying approaches across several pre- and postemergent herbicides in furrow-irrigated canefarming systems. The use of shielded sprayers (herbicide banding) provided herbicide load reductions extending substantially beyond simple proportionate decreases in amount of active herbicide ingredient applied to paddocks. These reductions were due largely to the extra management control available to irrigating growers in relation to where both herbicides and irrigation water can be applied to paddocks, coupled with knowledge of herbicide toxicological and physicochemical properties. Despite more complex herbicide mixtures being applied in banded practices, banding provided capacity for greatly reduced environmental toxicity in off-paddock losses. Similar toxicological and loss profiles of alternative herbicides relative to recently regulated pre-emergent herbicides highlight the need for a carefully considered approach to integrating alternative herbicides into improved pest management.

  2. Precise and rapid costal cartilage graft sectioning using a novel device: clinical application.

    PubMed

    Foulad, Allen; Hamamoto, Ashley; Manuel, Cyrus; Wong, Brian J

    2014-01-01

    IMPORTANCE The use of costal cartilage as a graft in facial reconstructive surgery requires sectioning the cartilage into a suitable shape. OBJECTIVE To evaluate the accuracy of a novel mechanical device for producing uniform slices of costal cartilage and to illustrate the use of the device during nasal surgery. DESIGN Basic and clinical study using 100 porcine ex vivo costal cartilage slices and 9 operative cases. METHODS This instrument departs from antecedent devices in that it uses compression to secure and stabilize the specimen during sectioning. A total of 75 porcine costal cartilage ribs were clamped with minimal compression just sufficient to secure and stabilize the specimen while cutting. Slices having a length of 4 cm and width of 1 cm were obtained using the cartilage cutter at 3 thicknesses: 1 mm (n = 25), 2 mm (n = 25), and 3 mm (n = 25). The procedure was repeated for the 2-mm thick samples; however, the ribs in this group (n = 25) were clamped using the maximum amount of compression attainable by the device. Thickness was measured using a digital micrometer. Case presentations illustrate the use of the device in secondary and reconstructive rhinoplasty surgery. RESULTS All specimens were highly uniform in thickness on visual inspection and appeared to be adequate for clinical application. Sectioning was completed in several seconds without complication. In the porcine specimens sectioned using minimal compression, the percentage difference in thickness for each individual sample averaged 18%, 10%, and 11% for the 1-mm-, 2-mm-, and 3-mm-thick slices, respectively. Within the specimens sectioned using maximum compression, the percentage difference in thickness for each individual sample averaged 35% for the 2-mm-thick slices. In the setting of nasal reconstructive surgery, slices having a thickness from 1 to 2 mm were found to be well suited for all necessary graft types. CONCLUSIONS AND RELEVANCE The simple mechanical device

  3. Food category consumption and obesity prevalence across countries: an application of Machine Learning method to big data analysis

    NASA Astrophysics Data System (ADS)

    Dunstan, Jocelyn; Fallah-Fini, Saeideh; Nau, Claudia; Glass, Thomas; Global Obesity Prevention Center Team

    The applications of sophisticated mathematical and numerical tools in public health has been demonstrated to be useful in predicting the outcome of public intervention as well as to study, for example, the main causes of obesity without doing experiments with the population. In this project we aim to understand which kind of food consumed in different countries over time best defines the rate of obesity in those countries. The use of Machine Learning is particularly useful because we do not need to create a hypothesis and test it with the data, but instead we learn from the data to find the groups of food that best describe the prevalence of obesity.

  4. IPAD applications to the design, analysis, and/or machining of aerospace structures. [Integrated Program for Aerospace-vehicle Design

    NASA Technical Reports Server (NTRS)

    Blackburn, C. L.; Dovi, A. R.; Kurtze, W. L.; Storaasli, O. O.

    1981-01-01

    A computer software system for the processing and integration of engineering data and programs, called IPAD (Integrated Programs for Aerospace-Vehicle Design), is described. The ability of the system to relieve the engineer of the mundane task of input data preparation is demonstrated by the application of a prototype system to the design, analysis, and/or machining of three simple structures. Future work to further enhance the system's automated data handling and ability to handle larger and more varied design problems are also presented.

  5. Problems in the application of a null lens for precise measurements of aspheric mirrors.

    PubMed

    Chkhalo, N I; Malyshev, I V; Pestov, A E; Polkovnikov, V N; Salashchenko, N N; Toropov, M N; Soloviev, A A

    2016-01-20

    Problems in the application of a null lens for surface shape measurements of aspherical mirrors are discussed using the example of manufacturing an aspherical concave mirror for the beyond extreme ultraviolet nanolithographer. A method for allowing measurement of the surface shape of a sample under study and the aberration of a null lens simultaneously, and for evaluating measurement accuracy, is described. Using this method, we made a mirror with an aspheric surface of the 6th order (i.e., the maximum deviation from the best-fit sphere is 6.6 μm) with the parameters of the deviations from the designed surface PV=5.3  nm and RMS=0.8  nm. An approximation of the surface shape was carried out using Zernike polynomials {Z(n)(m)(r,φ),m+n≤36}. The physical limitations of this technique are analyzed. It is shown that for aspheric measurements to an Angstrom accuracy, one needs to have a null lens with errors of less than 1 nm. For accurate measurements, it is necessary to establish compliance with the coordinates on the sample and on the interferogram.

  6. Tele-autonomous control involving contacts: The applications of a high precision laser line range sensor

    NASA Technical Reports Server (NTRS)

    Volz, R. A.; Shao, L.; Walker, M. W.; Conway, L. A.

    1989-01-01

    The object localization algorithm based on line-segment matching is presented. The method is very simple and computationally fast. In most cases, closed-form formulas are used to derive the solution. The method is also quite flexible, because only few surfaces (one or two) need to be accessed (sensed) to gather necessary range data. For example, if the line-segments are extracted from boundaries of a planar surface, only parameters of one surface and two of its boundaries need to be extracted, as compared with traditional point-surface matching or line-surface matching algorithms which need to access at least three surfaces in order to locate a planar object. Therefore, this method is especially suitable for applications when an object is surrounded by many other work pieces and most of the object is very difficult, is not impossible, to be measured; or when not all parts of the object can be reached. The theoretical ground on how to use line range sensor to located an object was laid. Much work has to be done in order to be really useful.

  7. Machine Shop Grinding Machines.

    ERIC Educational Resources Information Center

    Dunn, James

    This curriculum manual is one in a series of machine shop curriculum manuals intended for use in full-time secondary and postsecondary classes, as well as part-time adult classes. The curriculum can also be adapted to open-entry, open-exit programs. Its purpose is to equip students with basic knowledge and skills that will enable them to enter the…

  8. Potential application of machine learning in health outcomes research and some statistical cautions.

    PubMed

    Crown, William H

    2015-03-01

    Traditional analytic methods are often ill-suited to the evolving world of health care big data characterized by massive volume, complexity, and velocity. In particular, methods are needed that can estimate models efficiently using very large datasets containing healthcare utilization data, clinical data, data from personal devices, and many other sources. Although very large, such datasets can also be quite sparse (e.g., device data may only be available for a small subset of individuals), which creates problems for traditional regression models. Many machine learning methods address such limitations effectively but are still subject to the usual sources of bias that commonly arise in observational studies. Researchers using machine learning methods such as lasso or ridge regression should assess these models using conventional specification tests.

  9. Progressive Vector Quantization on a massively parallel SIMD machine with application to multispectral image data

    NASA Technical Reports Server (NTRS)

    Manohar, Mareboyana; Tilton, James C.

    1994-01-01

    A progressive vector quantization (VQ) compression approach is discussed which decomposes image data into a number of levels using full search VQ. The final level is losslessly compressed, enabling lossless reconstruction. The computational difficulties are addressed by implementation on a massively parallel SIMD machine. We demonstrate progressive VQ on multispectral imagery obtained from the Advanced Very High Resolution Radiometer instrument and other Earth observation image data, and investigate the trade-offs in selecting the number of decomposition levels and codebook training method.

  10. MACHINING ELIMINATION THROUGH APPLICATION OF THREAD FORMING FASTENERS IN NET SHAPED CAST HOLES

    SciTech Connect

    Cleaver, Ryan J; Cleaver, Todd H; Talbott, Richard

    2012-05-02

    The ultimate objective of this work was to eliminate approximately 30% of the machining performed in typical automotive engine and transmission plants by using thread forming fasteners in as-cast holes of aluminum and magnesium cast components. The primary issues at the source of engineers reluctance to implementing thread forming fasteners in lightweight castings are: * Little proof of consistency of clamp load vs. input torque in either aluminum or magnesium castings. * No known data to understand the effect on consistency of clamp load as casting dies wear. The clamp load consistency concern is founded in the fact that a portion of the input torque used to create clamp load is also used to create threads. The torque used for thread forming may not be consistent due to variations in casting material, hole size and shape due to tooling wear and process variation (thermal and mechanical). There is little data available to understand the magnitude of this concern or to form the basis of potential solutions if the range of clamp load variation is very high (> +/- 30%). The range of variation that can be expected in as-cast hole size and shape over the full life cycle of a high pressure die casting die was established in previous work completed by Pacific Northwest National Laboratory, (PNNL). This established range of variation was captured in a set of 12 cast bosses by designing core pins at the size and draft angles identified in the sited previous work. The cast bosses were cut into nuts that could be used in the Ford Fastener Laboratory test-cell to measure clamp load when a thread forming fastener was driven into a cast nut. There were two sets of experiments run. First, a series of cast aluminum nuts were made reflecting the range of shape and size variations to be expected over the life cycle of a die casting die. Taptite thread forming fasteners, (a widely used thread forming fastener suitable for aluminum applications), were driven into the various cored, as

  11. On detector linearity and precision of beam shift detection for quantitative differential phase contrast applications.

    PubMed

    Zweck, Josef; Schwarzhuber, Felix; Wild, Johannes; Galioit, Vincent

    2016-09-01

    Differential phase contrast is a STEM imaging mode where minute sideways deflections of the electron probe are monitored, usually by using a position sensitive device (Chapman, 1984 [1]; Lohr et al., 2012 [2]) or, alternatively in some cases, a fast camera (Müller et al., 2012 [3,4]; Yang et al., 2015 [5]; Pennycook et al., 2015 [6]) as a pixelated detector. While traditionally differential phase contrast electron microscopy was mainly focused on investigations of micro-magnetic domain structures and their specific features, such as domain wall widths, etc. (Chapman, 1984 [1]; Chapman et al., 1978, 1981, 1985 [7-9]; Sannomiya et al., 2004 [10]), its usage has recently been extended to mesoscopic (Lohr et al., 2012, 2016 [2,12]; Bauer et al., 2014 [11]; Shibata et al., 2015 [13]) and nano-scale electric fields (Shibata et al., 2012 [14]; Mueller et al., 2014 [15]). In this paper, the various interactions which can cause a beam deflection are reviewed and expanded by two so far undiscussed mechanisms which may be important for biological applications. As differential phase contrast microscopy strongly depends on the ability to detect minute beam deflections we first treat the linearity problem for an annular four quadrant detector and then determine the factors which limit the minimum measurable deflection angle, such as S/N ratio, current density, dwell time and detector geometry. Knowing these factors enables the experimenter to optimize the set-up for optimum performance of the microscope and to get a clear figure for the achievable field resolution error margins.

  12. Gesture-controlled interfaces for self-service machines and other applications

    NASA Technical Reports Server (NTRS)

    Cohen, Charles J. (Inventor); Beach, Glenn (Inventor); Cavell, Brook (Inventor); Foulk, Gene (Inventor); Jacobus, Charles J. (Inventor); Obermark, Jay (Inventor); Paul, George (Inventor)

    2004-01-01

    A gesture recognition interface for use in controlling self-service machines and other devices is disclosed. A gesture is defined as motions and kinematic poses generated by humans, animals, or machines. Specific body features are tracked, and static and motion gestures are interpreted. Motion gestures are defined as a family of parametrically delimited oscillatory motions, modeled as a linear-in-parameters dynamic system with added geometric constraints to allow for real-time recognition using a small amount of memory and processing time. A linear least squares method is preferably used to determine the parameters which represent each gesture. Feature position measure is used in conjunction with a bank of predictor bins seeded with the gesture parameters, and the system determines which bin best fits the observed motion. Recognizing static pose gestures is preferably performed by localizing the body/object from the rest of the image, describing that object, and identifying that description. The disclosure details methods for gesture recognition, as well as the overall architecture for using gesture recognition to control of devices, including self-service machines.

  13. Analytical Modeling of a Novel Transverse Flux Machine for Direct Drive Wind Turbine Applications

    SciTech Connect

    Hasan, IIftekhar; Husain, Tausif; Uddin, Md Wasi; Sozer, Yilmaz; Husain, Iqbal; Muljadi, Eduard

    2015-09-02

    This paper presents a nonlinear analytical model of a novel double sided flux concentrating Transverse Flux Machine (TFM) based on the Magnetic Equivalent Circuit (MEC) model. The analytical model uses a series-parallel combination of flux tubes to predict the flux paths through different parts of the machine including air gaps, permanent magnets (PM), stator, and rotor. The two-dimensional MEC model approximates the complex three-dimensional flux paths of the TFM and includes the effects of magnetic saturation. The model is capable of adapting to any geometry which makes it a good alternative for evaluating prospective designs of TFM as compared to finite element solvers which are numerically intensive and require more computation time. A single phase, 1 kW, 400 rpm machine is analytically modeled and its resulting flux distribution, no-load EMF and torque, verified with Finite Element Analysis (FEA). The results are found to be in agreement with less than 5% error, while reducing the computation time by 25 times.

  14. Analytical Modeling of a Novel Transverse Flux Machine for Direct Drive Wind Turbine Applications: Preprint

    SciTech Connect

    Hasan, IIftekhar; Husain, Tausif; Uddin, Md Wasi; Sozer, Yilmaz; Husain; Iqbal; Muljadi, Eduard

    2015-08-24

    This paper presents a nonlinear analytical model of a novel double-sided flux concentrating Transverse Flux Machine (TFM) based on the Magnetic Equivalent Circuit (MEC) model. The analytical model uses a series-parallel combination of flux tubes to predict the flux paths through different parts of the machine including air gaps, permanent magnets, stator, and rotor. The two-dimensional MEC model approximates the complex three-dimensional flux paths of the TFM and includes the effects of magnetic saturation. The model is capable of adapting to any geometry that makes it a good alternative for evaluating prospective designs of TFM compared to finite element solvers that are numerically intensive and require more computation time. A single-phase, 1-kW, 400-rpm machine is analytically modeled, and its resulting flux distribution, no-load EMF, and torque are verified with finite element analysis. The results are found to be in agreement, with less than 5% error, while reducing the computation time by 25 times.

  15. Application of support vector machines to breast cancer screening using mammogram and history data

    NASA Astrophysics Data System (ADS)

    Land, Walker H., Jr.; Akanda, Anab; Lo, Joseph Y.; Anderson, Francis; Bryden, Margaret

    2002-05-01

    Support Vector Machines (SVMs) are a new and radically different type of classifiers and learning machines that use a hypothesis space of linear functions in a high dimensional feature space. This relatively new paradigm, based on Statistical Learning Theory (SLT) and Structural Risk Minimization (SRM), has many advantages when compared to traditional neural networks, which are based on Empirical Risk Minimization (ERM). Unlike neural networks, SVM training always finds a global minimum. Furthermore, SVMs have inherent ability to solve pattern classification without incorporating any problem-domain knowledge. In this study, the SVM was employed as a pattern classifier, operating on mammography data used for breast cancer detection. The main focus was to formulate the best learning machine configurations for optimum specificity and positive predictive value at very high sensitivities. Using a mammogram database of 500 biopsy-proven samples, the best performing SVM, on average, was able to achieve (under statistical 5-fold cross-validation) a specificity of 45.0% and a positive predictive value (PPV) of 50.1% at 100% sensitivity. At 97% sensitivity, a specificity of 55.8% and a PPV of 55.2% were obtained.

  16. Spectroscopic studies on chemical- and photo-responsive molecular machines and their bio-applications

    NASA Astrophysics Data System (ADS)

    Lau, Yuen Agnes

    2011-07-01

    The four chapters presented in this dissertation describe how various spectroscopic techniques are used: 1) to study the operation of molecular machines in solution, 2) to track the operation of molecular machines inside a single cell, and 3) to investigate the photo-decomposition pathway of a biological chromophore. Recent advances in nanotechnology have enriched the development of nano-scale molecular assemblies to be used as delivery platforms for biologically relevant molecules. Among all the molecular assemblies, molecular machines that are incorporated onto various domains of mesoporous silica nanoparticles (MSN) hold considerable potential as a reliable delivery system. Because the ease of functionalization enables chemical or photo-responsive molecular moieties to be covalently attached to the silica framework, these molecular assemblies, with defined mechanized properties, can perform specific functions under external stimuli (pH, redox, or light). While the primary function of these molecular machines is to deliver stored cargo molecules, the means of activation and the motif in which they operate are different. In the first and second chapters of this dissertation, two types of molecular machines, nanovalves and nanoimpellers, and their operations are studied. The ability to continuously monitor and image progression of molecular-based biological events in real-time can enhance our understanding of intracellular processes upon drug, protein and nucleic acid delivery. Using the photo-activated nanoimpeller described in the second chapter, the third chapter explores how it can be used to transport a nuclear staining agent, PI, inside a single cell. Nanoimpellers are made by functionalizing azobenzene molecules to the internal pore surface of MSN. The continuous cis/trans isomerizations are set in motion upon laser illumination at optimal wavelength(s), which facilitate cargo molecules to be expelled from the pores to the surrounding medium. By refining a

  17. Multiple man-machine interfaces

    NASA Technical Reports Server (NTRS)

    Stanton, L.; Cook, C. W.

    1981-01-01

    The multiple man machine interfaces inherent in military pilot training, their social implications, and the issue of possible negative feedback were explored. Modern technology has produced machines which can see, hear, and touch with greater accuracy and precision than human beings. Consequently, the military pilot is more a systems manager, often doing battle against a target he never sees. It is concluded that unquantifiable human activity requires motivation that is not intrinsic in a machine.

  18. Electrochemical machining in-process data collection and control

    SciTech Connect

    Neal, R.E.

    1980-09-01

    Electrochemical machining (ECM) is a fast and efficient method to fabricate intricate metal parts. However, tooling is often expensive; and electical power consumption is relatively high. The precision of an ECM process is dependent upon several variables which often cannot be predicted in the initial tool design. This leads to iterative tool adjustments until the desired level of precision is achieved. A system was devised to use a computer for collecting data from the ECM process and for monitoring and controlling ECM operations. It is believed that these data collections and analyses will lead to the formulation of algorithms to produce parts with better tolerances and will allow more efficient uses of the ECM machines. One algorithm has been developed to allow the efficient ECM of large-surface-area parts. Such programs and equipment will enhance the competitive position of the ECM process in machining applications previously performed by more conventional methods while minimizing electrical power consumption.

  19. The application of machine learning in multi sensor data fusion for activity recognition in mobile device space

    NASA Astrophysics Data System (ADS)

    Marhoubi, Asmaa H.; Saravi, Sara; Edirisinghe, Eran A.

    2015-05-01

    The present generation of mobile handheld devices comes equipped with a large number of sensors. The key sensors include the Ambient Light Sensor, Proximity Sensor, Gyroscope, Compass and the Accelerometer. Many mobile applications are driven based on the readings obtained from either one or two of these sensors. However the presence of multiple-sensors will enable the determination of more detailed activities that are carried out by the user of a mobile device, thus enabling smarter mobile applications to be developed that responds more appropriately to user behavior and device usage. In the proposed research we use recent advances in machine learning to fuse together the data obtained from all key sensors of a mobile device. We investigate the possible use of single and ensemble classifier based approaches to identify a mobile device's behavior in the space it is present. Feature selection algorithms are used to remove non-discriminant features that often lead to poor classifier performance. As the sensor readings are noisy and include a significant proportion of missing values and outliers, we use machine learning based approaches to clean the raw data obtained from the sensors, before use. Based on selected practical case studies, we demonstrate the ability to accurately recognize device behavior based on multi-sensor data fusion.

  20. Comparison of machine learning algorithms for their applicability in satellite-based optical rainfall retrievals

    NASA Astrophysics Data System (ADS)

    Meyer, Hanna; Kühnlein, Meike; Appelhans, Tim; Nauss, Thomas

    2015-04-01

    Machine learning (ML) algorithms have been successfully evaluated as valuable tools in satellite-based rainfall retrievals which shows the high potential of ML algorithms when faced with high dimensional and complex data. Moreover, the recent developments in parallel computing with ML offer new possibilities in terms of training and predicting speed and therefore makes their usage in real time systems feasible. The present study compares four ML algorithms for rainfall area detection and rainfall rate assignment during daytime, night-time and twilight using MSG SEVIRI data over Germany. Satellite-based proxies for cloud top height, cloud top temperature, cloud phase and cloud water path are applied as predictor variables. As machine learning algorithms, random forests (RF), neural networks (NNET), averaged neural networks (AVNNET) and support vector machines (SVM) are chosen. The comparison is realised in three steps. First, an extensive tuning study is carried out to customise each of the models. Secondly, the models are trained using the optimum values of model parameters found in the tuning study. Finally, the trained models are used to detect rainfall areas and to assign rainfall rates using an independent validation datasets which is compared against ground-based radar data. To train and validate the models, the radar-based RADOLAN RW product from the German Weather Service (DWD) is used which provides area-wide gauge-adjusted hourly precipitation information. Though the differences in the performance of the algorithms were rather small, NNET and AVNNET have been identified as the most suitable algorithms. On average, they showed the best performance in rainfall area delineation as well as in rainfall rate assignment. The fast computation time of NNET allows to work with large datasets as it is required in remote sensing based rainfall retrievals. However, since none of the algorithms performed considerably better that the others we conclude that research

  1. Application of Machine Learning Techniques to High-Dimensional Clinical Data to Forecast Postoperative Complications

    PubMed Central

    Thottakkara, Paul; Ozrazgat-Baslanti, Tezcan; Hupf, Bradley B.; Rashidi, Parisa; Pardalos, Panos; Momcilovic, Petar

    2016-01-01

    Objective To compare performance of risk prediction models for forecasting postoperative sepsis and acute kidney injury. Design Retrospective single center cohort study of adult surgical patients admitted between 2000 and 2010. Patients 50,318 adult patients undergoing major surgery. Measurements We evaluated the performance of logistic regression, generalized additive models, naïve Bayes and support vector machines for forecasting postoperative sepsis and acute kidney injury. We assessed the impact of feature reduction techniques on predictive performance. Model performance was determined using the area under the receiver operating characteristic curve, accuracy, and positive predicted value. The results were reported based on a 70/30 cross validation procedure where the data were randomly split into 70% used for training the model and the 30% for validation. Main Results The areas under the receiver operating characteristic curve for different models ranged between 0.797 and 0.858 for acute kidney injury and between 0.757 and 0.909 for severe sepsis. Logistic regression, generalized additive model, and support vector machines had better performance compared to Naïve Bayes model. Generalized additive models additionally accounted for non-linearity of continuous clinical variables as depicted in their risk patterns plots. Reducing the input feature space with LASSO had minimal effect on prediction performance, while feature extraction using principal component analysis improved performance of the models. Conclusions Generalized additive models and support vector machines had good performance as risk prediction model for postoperative sepsis and AKI. Feature extraction using principal component analysis improved the predictive performance of all models. PMID:27232332

  2. Application of machine learning for the evaluation of turfgrass plots using aerial images

    NASA Astrophysics Data System (ADS)

    Ding, Ke; Raheja, Amar; Bhandari, Subodh; Green, Robert L.

    2016-05-01

    Historically, investigation of turfgrass characteristics have been limited to visual ratings. Although relevant information may result from such evaluations, final inferences may be questionable because of the subjective nature in which the data is collected. Recent advances in computer vision techniques allow researchers to objectively measure turfgrass characteristics such as percent ground cover, turf color, and turf quality from the digital images. This paper focuses on developing a methodology for automated assessment of turfgrass quality from aerial images. Images of several turfgrass plots of varying quality were gathered using a camera mounted on an unmanned aerial vehicle. The quality of these plots were also evaluated based on visual ratings. The goal was to use the aerial images to generate quality evaluations on a regular basis for the optimization of water treatment. Aerial images are used to train a neural network so that appropriate features such as intensity, color, and texture of the turfgrass are extracted from these images. Neural network is a nonlinear classifier commonly used in machine learning. The output of the neural network trained model is the ratings of the grass, which is compared to the visual ratings. Currently, the quality and the color of turfgrass, measured as the greenness of the grass, are evaluated. The textures are calculated using the Gabor filter and co-occurrence matrix. Other classifiers such as support vector machines and simpler linear regression models such as Ridge regression and LARS regression are also used. The performance of each model is compared. The results show encouraging potential for using machine learning techniques for the evaluation of turfgrass quality and color.

  3. Application of support vector machine and quantum genetic algorithm in infrared target recognition

    NASA Astrophysics Data System (ADS)

    Wang, Hongliang; Huang, Yangwen; Ding, Haifei

    2010-08-01

    In this paper, a kind of classifier based on support vector machine (SVM) is designed for infrared target recognition. In allusion to the problem how to choose kernel parameter and error penalty factor, quantum genetic algorithm (QGA) is used to optimize the parameters of SVM model, it overcomes the shortcoming of determining its parameters after trial and error in the past. Classification experiments of infrared target features extracted by this method show that the convergence speed is fast and the rate of accurate recognition is high.

  4. Applying Computational Aesthetics to a Video Game Application Using Machine Learning.

    PubMed

    Erdem, Ali Naci; Halici, Ugur

    2016-01-01

    The authors have developed a novel approach to evaluating the aesthetic quality of the camera direction in video game scenes rendered in real time while the game is being played. Their goal was to improve the visual aesthetic quality of computer-generated images using a computational aesthetics approach via a regression machine learning model. Considering the challenges and limitations involved, the proposed approach yielded promising prediction performance. The results show that near-real-time aesthetic analysis and visual improvement is possible using a virtual camera director. PMID:27244720

  5. Applying Computational Aesthetics to a Video Game Application Using Machine Learning.

    PubMed

    Erdem, Ali Naci; Halici, Ugur

    2016-01-01

    The authors have developed a novel approach to evaluating the aesthetic quality of the camera direction in video game scenes rendered in real time while the game is being played. Their goal was to improve the visual aesthetic quality of computer-generated images using a computational aesthetics approach via a regression machine learning model. Considering the challenges and limitations involved, the proposed approach yielded promising prediction performance. The results show that near-real-time aesthetic analysis and visual improvement is possible using a virtual camera director.

  6. Application of machine learning and expert systems to Statistical Process Control (SPC) chart interpretation

    NASA Technical Reports Server (NTRS)

    Shewhart, Mark

    1991-01-01

    Statistical Process Control (SPC) charts are one of several tools used in quality control. Other tools include flow charts, histograms, cause and effect diagrams, check sheets, Pareto diagrams, graphs, and scatter diagrams. A control chart is simply a graph which indicates process variation over time. The purpose of drawing a control chart is to detect any changes in the process signalled by abnormal points or patterns on the graph. The Artificial Intelligence Support Center (AISC) of the Acquisition Logistics Division has developed a hybrid machine learning expert system prototype which automates the process of constructing and interpreting control charts.

  7. Precision cosmological parameter estimation

    NASA Astrophysics Data System (ADS)

    Fendt, William Ashton, Jr.

    2009-09-01

    Experimental efforts of the last few decades have brought. a golden age to mankind's endeavor to understand tine physical properties of the Universe throughout its history. Recent measurements of the cosmic microwave background (CMB) provide strong confirmation of the standard big bang paradigm, as well as introducing new mysteries, to unexplained by current physical models. In the following decades. even more ambitious scientific endeavours will begin to shed light on the new physics by looking at the detailed structure of the Universe both at very early and recent times. Modern data has allowed us to begins to test inflationary models of the early Universe, and the near future will bring higher precision data and much stronger tests. Cracking the codes hidden in these cosmological observables is a difficult and computationally intensive problem. The challenges will continue to increase as future experiments bring larger and more precise data sets. Because of the complexity of the problem, we are forced to use approximate techniques and make simplifying assumptions to ease the computational workload. While this has been reasonably sufficient until now, hints of the limitations of our techniques have begun to come to light. For example, the likelihood approximation used for analysis of CMB data from the Wilkinson Microwave Anistropy Probe (WMAP) satellite was shown to have short falls, leading to pre-emptive conclusions drawn about current cosmological theories. Also it can he shown that an approximate method used by all current analysis codes to describe the recombination history of the Universe will not be sufficiently accurate for future experiments. With a new CMB satellite scheduled for launch in the coming months, it is vital that we develop techniques to improve the analysis of cosmological data. This work develops a novel technique of both avoiding the use of approximate computational codes as well as allowing the application of new, more precise analysis

  8. Fault Tolerant State Machines

    NASA Technical Reports Server (NTRS)

    Burke, Gary R.; Taft, Stephanie

    2004-01-01

    State machines are commonly used to control sequential logic in FPGAs and ASKS. An errant state machine can cause considerable damage to the device it is controlling. For example in space applications, the FPGA might be controlling Pyros, which when fired at the wrong time will cause a mission failure. Even a well designed state machine can be subject to random errors us a result of SEUs from the radiation environment in space. There are various ways to encode the states of a state machine, and the type of encoding makes a large difference in the susceptibility of the state machine to radiation. In this paper we compare 4 methods of state machine encoding and find which method gives the best fault tolerance, as well as determining the resources needed for each method.

  9. Application of electrochemical techniques for machining titanium aluminide-based alloys

    SciTech Connect

    Ziomek-Moroz, M.; Su, W; Alman, David E.; Hawk, Jeffrey A.

    1997-01-01

    Intermetallic materials with excellent resistance to high-temperature oxidation have been considered as potential replacements for superalloys used as aerospace materials. Titanium aluminides are especially attractive for this role. However, further commercialization of titanium aluminides requires the development of non-conventional machining, such as electrochemical machining (ECM). As a first attempt in the development of the ECM process, the corrosion behavior of arc-melted gamma TiAl and alpha 2 Ti3Al was investigated along with pure titanium and aluminum in deaerated and non-deaerated solutions of sulfuric acid, sodium sulfate, and sodium hydroxide. Two types of electrochemical experiments were carried out, namely, potentiodynamic and potentiostatic. In the Na2SO4 solution, the highest current was found for Al and the lowest for TiAl. The shape of the polarization curves indicates that the intermetallics show similar behavior to that of Ti. It has been found that, in sulfuric acid, current values decrease with increasing titanium content. In the sodium sulfate and sodium hydroxide solutions, current values initially decrease with increasing titanium content and remain unchanged for higher concentrations of titanium.

  10. A Boltzmann machine for the organization of intelligent machines

    NASA Technical Reports Server (NTRS)

    Moed, Michael C.; Saridis, George N.

    1989-01-01

    In the present technological society, there is a major need to build machines that would execute intelligent tasks operating in uncertain environments with minimum interaction with a human operator. Although some designers have built smart robots, utilizing heuristic ideas, there is no systematic approach to design such machines in an engineering manner. Recently, cross-disciplinary research from the fields of computers, systems AI and information theory has served to set the foundations of the emerging area of the design of intelligent machines. Since 1977 Saridis has been developing an approach, defined as Hierarchical Intelligent Control, designed to organize, coordinate and execute anthropomorphic tasks by a machine with minimum interaction with a human operator. This approach utilizes analytical (probabilistic) models to describe and control the various functions of the intelligent machine structured by the intuitively defined principle of Increasing Precision with Decreasing Intelligence (IPDI) (Saridis 1979). This principle, even though resembles the managerial structure of organizational systems (Levis 1988), has been derived on an analytic basis by Saridis (1988). The purpose is to derive analytically a Boltzmann machine suitable for optimal connection of nodes in a neural net (Fahlman, Hinton, Sejnowski, 1985). Then this machine will serve to search for the optimal design of the organization level of an intelligent machine. In order to accomplish this, some mathematical theory of the intelligent machines will be first outlined. Then some definitions of the variables associated with the principle, like machine intelligence, machine knowledge, and precision will be made (Saridis, Valavanis 1988). Then a procedure to establish the Boltzmann machine on an analytic basis will be presented and illustrated by an example in designing the organization level of an Intelligent Machine. A new search technique, the Modified Genetic Algorithm, is presented and proved

  11. Applicability of rat precision-cut lung slices in evaluating nanomaterial cytotoxicity, apoptosis, oxidative stress, and inflammation

    SciTech Connect

    Sauer, Ursula G.; Vogel, Sandra; Aumann, Alexandra; Hess, Annemarie; Kolle, Susanne N.; Ma-Hock, Lan; Wohlleben, Wendel; Dammann, Martina; Strauss, Volker; Treumann, Silke; Gröters, Sibylle; Wiench, Karin; Ravenzwaay, Bennard van; Landsiedel, Robert

    2014-04-01

    The applicability of rat precision-cut lung slices (PCLuS) in detecting nanomaterial (NM) toxicity to the respiratory tract was investigated evaluating sixteen OECD reference NMs (TiO{sub 2}, ZnO, CeO{sub 2}, SiO{sub 2}, Ag, multi-walled carbon nanotubes (MWCNTs)). Upon 24-hour test substance exposure, the PCLuS system was able to detect early events of NM toxicity: total protein, reduction in mitochondrial activity, caspase-3/-7 activation, glutathione depletion/increase, cytokine induction, and histopathological evaluation. Ion shedding NMS (ZnO and Ag) induced severe tissue destruction detected by the loss of total protein. Two anatase TiO{sub 2} NMs, CeO{sub 2} NMs, and two MWCNT caused significant (determined by trend analysis) cytotoxicity in the WST-1 assay. At non-cytotoxic concentrations, different TiO{sub 2} NMs and one MWCNT increased GSH levels, presumably a defense response to reactive oxygen species, and these substances further induced a variety of cytokines. One of the SiO{sub 2} NMs increased caspase-3/-7 activities at non-cytotoxic levels, and one rutile TiO{sub 2} only induced cytokines. Investigating these effects is, however, not sufficient to predict apical effects found in vivo. Reproducibility of test substance measurements was not fully satisfactory, especially in the GSH and cytokine assays. Effects were frequently observed in negative controls pointing to tissue slice vulnerability even though prepared and handled with utmost care. Comparisons of the effects observed in the PCLuS to in vivo effects reveal some concordances for the metal oxide NMs, but less so for the MWCNT. The highest effective dosages, however, exceeded those reported for rat short-term inhalation studies. To become applicable for NM testing, the PCLuS system requires test protocol optimization. - Highlights: • 16 OECD reference nanomaterials were tested in rat precision-cut lung slices. • Nanomaterial cytotoxicity, apoptose, oxidative stress, and inflammation were

  12. Vibration control for precision manufacturing at Sandia National Laboratories

    SciTech Connect

    Hinnerichs, T.; Martinez, D.

    1995-04-01

    Sandia National Laboratories performs R and D in structural dynamics and vibration suppression for precision applications in weapon systems, space, underwater, transportation and civil structures. Over the last decade these efforts have expanded into the areas of active vibration control and ``smart`` structures and material systems. In addition, Sandia has focused major resources towards technology to support weapon product development and agile manufacturing capability for defense and industrial applications. This paper will briefly describe the structural dynamics modeling and verification process currently in place at Sandia that supports vibration control and some specific applications of these techniques to manufacturing in the areas of lithography, machine tools and flexible robotics.

  13. Machine learning and radiology.

    PubMed

    Wang, Shijun; Summers, Ronald M

    2012-07-01

    In this paper, we give a short introduction to machine learning and survey its applications in radiology. We focused on six categories of applications in radiology: medical image segmentation, registration, computer aided detection and diagnosis, brain function or activity analysis and neurological disease diagnosis from fMR images, content-based image retrieval systems for CT or MRI images, and text analysis of radiology reports using natural language processing (NLP) and natural language understanding (NLU). This survey shows that machine learning plays a key role in many radiology applications. Machine learning identifies complex patterns automatically and helps radiologists make intelligent decisions on radiology data such as conventional radiographs, CT, MRI, and PET images and radiology reports. In many applications, the performance of machine learning-based automatic detection and diagnosis systems has shown to be comparable to that of a well-trained and experienced radiologist. Technology development in machine learning and radiology will benefit from each other in the long run. Key contributions and common characteristics of machine learning techniques in radiology are discussed. We also discuss the problem of translating machine learning applications to the radiology clinical setting, including advantages and potential barriers.

  14. Machine Learning and Radiology

    PubMed Central

    Wang, Shijun; Summers, Ronald M.

    2012-01-01

    In this paper, we give a short introduction to machine learning and survey its applications in radiology. We focused on six categories of applications in radiology: medical image segmentation, registration, computer aided detection and diagnosis, brain function or activity analysis and neurological disease diagnosis from fMR images, content-based image retrieval systems for CT or MRI images, and text analysis of radiology reports using natural language processing (NLP) and natural language understanding (NLU). This survey shows that machine learning plays a key role in many radiology applications. Machine learning identifies complex patterns automatically and helps radiologists make intelligent decisions on radiology data such as conventional radiographs, CT, MRI, and PET images and radiology reports. In many applications, the performance of machine learning-based automatic detection and diagnosis systems has shown to be comparable to that of a well-trained and experienced radiologist. Technology development in machine learning and radiology will benefit from each other in the long run. Key contributions and common characteristics of machine learning techniques in radiology are discussed. We also discuss the problem of translating machine learning applications to the radiology clinical setting, including advantages and potential barriers. PMID:22465077

  15. A state dynamics method for integrated GPS/INS navigation and its application to aircraft precision approach

    NASA Astrophysics Data System (ADS)

    Chan, Fang-Cheng

    In recent years, GPS navigation systems have found widespread use in many diverse applications. The achievements of GPS navigation systems in positioning and navigation services have been nothing short of extraordinary. With the use of carrier phase measurements and Differential GPS (DGPS), centimeter-level performance is achievable today. Therefore, the principal issues for modern navigation are not related to accuracy per se, but robustness. Unfortunately in this regard, all radionavigation systems are subject to Radio Frequency Interference (RFI). In response, this research is focused on the development of interference-robust navigation systems for aviation applications. A new dual-frequency Carrier-phase DGPS (CDGPS) architecture has been developed in this research and its performance was evaluated relative to the requirements for a unique shipboard landing application. RFI vulnerability was addressed for this application by directly incorporating a single frequency architecture as a back-up in the event of hostile jamming on one frequency. For critical civil aviation applications without access to dual frequency GPS signals, a novel method for tightly-coupling GPS and Inertial Navigation Sensors (INS) was developed to address the signal vulnerability issue. The new hybrid navigation system, based on the direct fusion of GPS and INS using state dynamics, is a mathematically rigorous approach, yet it is more direct and simpler to implement than existing GPS/INS integration schemes. The hybrid navigation system was validated with flight data, and predicted system performance was evaluated using a covariance analysis method. Necessary conditions on INS sensor and gravity model quality were derived to ensure that the hybrid system performance is compliant with navigation requirements for aircraft precision approach and landing. In addition, a new fault detection algorithm, based on integrated Kalman filter innovations, was developed and evaluated against other

  16. The research and application of visual saliency and adaptive support vector machine in target tracking field.

    PubMed

    Chen, Yuantao; Xu, Weihong; Kuang, Fangjun; Gao, Shangbing

    2013-01-01

    The efficient target tracking algorithm researches have become current research focus of intelligent robots. The main problems of target tracking process in mobile robot face environmental uncertainty. They are very difficult to estimate the target states, illumination change, target shape changes, complex backgrounds, and other factors and all affect the occlusion in tracking robustness. To further improve the target tracking's accuracy and reliability, we present a novel target tracking algorithm to use visual saliency and adaptive support vector machine (ASVM). Furthermore, the paper's algorithm has been based on the mixture saliency of image features. These features include color, brightness, and sport feature. The execution process used visual saliency features and those common characteristics have been expressed as the target's saliency. Numerous experiments demonstrate the effectiveness and timeliness of the proposed target tracking algorithm in video sequences where the target objects undergo large changes in pose, scale, and illumination. PMID:24363779

  17. Application of the support vector machine to predict subclinical mastitis in dairy cattle.

    PubMed

    Mammadova, Nazira; Keskin, Ismail

    2013-01-01

    This study presented a potentially useful alternative approach to ascertain the presence of subclinical and clinical mastitis in dairy cows using support vector machine (SVM) techniques. The proposed method detected mastitis in a cross-sectional representative sample of Holstein dairy cattle milked using an automatic milking system. The study used such suspected indicators of mastitis as lactation rank, milk yield, electrical conductivity, average milking duration, and control season as input data. The output variable was somatic cell counts obtained from milk samples collected monthly throughout the 15 months of the control period. Cattle were judged to be healthy or infected based on those somatic cell counts. This study undertook a detailed scrutiny of the SVM methodology, constructing and examining a model which showed 89% sensitivity, 92% specificity, and 50% error in mastitis detection. PMID:24574862

  18. Hard permanent magnet development trends and their application to A.C. machines

    NASA Technical Reports Server (NTRS)

    Mildrum, H. F.

    1981-01-01

    The physical and magnetic properties of Mn-Al-C, Fe-Cr-Co, and RE-TM (rare earth-transition metal intermetallics) in polymer and soft metal bonded or sintered form are considered for ac circuit machine usage. The manufacturing processes for the magnetic materials are reviewed, and the mechanical and electrical properties of the magnetic materials are compared, with consideration given to the reference Alnico magnet. The Mn-Al-C magnets have the same magnetic properties and costs as Alnico units, operate well at low temperatures, but have poor high temperature performance. Fe-Cr-Co magnets also have comparable cost to Alnico magnets, and operate at high or low temperature, but are brittle, expensive, and contain Co. RE-Co magnets possess a high energy density, operate well in a wide temperature range, and are expensive. Recommendation for exploring the rare-earth alternatives are offered.

  19. A Relevance Vector Machine-Based Approach with Application to Oil Sand Pump Prognostics

    PubMed Central

    Hu, Jinfei; Tse, Peter W.

    2013-01-01

    Oil sand pumps are widely used in the mining industry for the delivery of mixtures of abrasive solids and liquids. Because they operate under highly adverse conditions, these pumps usually experience significant wear. Consequently, equipment owners are quite often forced to invest substantially in system maintenance to avoid unscheduled downtime. In this study, an approach combining relevance vector machines (RVMs) with a sum of two exponential functions was developed to predict the remaining useful life (RUL) of field pump impellers. To handle field vibration data, a novel feature extracting process was proposed to arrive at a feature varying with the development of damage in the pump impellers. A case study involving two field datasets demonstrated the effectiveness of the developed method. Compared with standalone exponential fitting, the proposed RVM-based model was much better able to predict the remaining useful life of pump impellers. PMID:24051527

  20. Application of Adomian Decomposition for Multi-Machine Power System Simulation

    SciTech Connect

    Gurrala, Gurunath; Dimitrovski, Aleksandar D; Pannala, Sreekanth; Simunovic, Srdjan; Starke, Michael R; Sun, Kai

    2015-01-01

    In this paper, the merits of Adomian Decomposition Method (ADM) have been investigated for the time domain simulation of multi-machine power systems. ADM is an analytical approximation method for the solution of linear, nonlinear, deterministic and stochastic operator equations. It approximates the nonlinearities in the equations using Adomian polynomial series and that can form a rapidly convergent sequence of analytic functions. We apply the ADM approach for simulation of differential algebraic equations representing the detailed multimachine power system. The ADM approach has been applied on the widely used IEEE 3 generator 9 bus system and IEEE 10 generator 39 bus system for 3 fault simulations. In our simulations we found that the ADM approach is faster than the standard trapezoidal time integration method for the comparable accuracy.

  1. Predicting ground contact events for a continuum of gait types: An application of targeted machine learning using principal component analysis.

    PubMed

    Osis, Sean T; Hettinga, Blayne A; Ferber, Reed

    2016-05-01

    An ongoing challenge in the application of gait analysis to clinical settings is the standardized detection of temporal events, with unobtrusive and cost-effective equipment, for a wide range of gait types. The purpose of the current study was to investigate a targeted machine learning approach for the prediction of timing for foot strike (or initial contact) and toe-off, using only kinematics for walking, forefoot running, and heel-toe running. Data were categorized by gait type and split into a training set (∼30%) and a validation set (∼70%). A principal component analysis was performed, and separate linear models were trained and validated for foot strike and toe-off, using ground reaction force data as a gold-standard for event timing. Results indicate the model predicted both foot strike and toe-off timing to within 20ms of the gold-standard for more than 95% of cases in walking and running gaits. The machine learning approach continues to provide robust timing predictions for clinical use, and may offer a flexible methodology to handle new events and gait types. PMID:27131183

  2. Man-Machine Integration Design and Analysis System (MIDAS) v5: Augmentations, Motivations, and Directions for Aeronautics Applications

    NASA Technical Reports Server (NTRS)

    Gore, Brian F.

    2011-01-01

    As automation and advanced technologies are introduced into transport systems ranging from the Next Generation Air Transportation System termed NextGen, to the advanced surface transportation systems as exemplified by the Intelligent Transportations Systems, to future systems designed for space exploration, there is an increased need to validly predict how the future systems will be vulnerable to error given the demands imposed by the assistive technologies. One formalized approach to study the impact of assistive technologies on the human operator in a safe and non-obtrusive manner is through the use of human performance models (HPMs). HPMs play an integral role when complex human-system designs are proposed, developed, and tested. One HPM tool termed the Man-machine Integration Design and Analysis System (MIDAS) is a NASA Ames Research Center HPM software tool that has been applied to predict human-system performance in various domains since 1986. MIDAS is a dynamic, integrated HPM and simulation environment that facilitates the design, visualization, and computational evaluation of complex man-machine system concepts in simulated operational environments. The paper will discuss a range of aviation specific applications including an approach used to model human error for NASA s Aviation Safety Program, and what-if analyses to evaluate flight deck technologies for NextGen operations. This chapter will culminate by raising two challenges for the field of predictive HPMs for complex human-system designs that evaluate assistive technologies: that of (1) model transparency and (2) model validation.

  3. CONCEPTUAL DESIGN FOR A RADICALLY SMALLER, HIGHLY ADAPTIVE AND APPLICATION-FLEXIBLE MINING MACHINE FOR UTILITY AND DEVELOPMENT WORK

    SciTech Connect

    Andrew H. Stern

    2004-12-20

    The aim of this research project was to develop a preliminary ''conceptual design'' for a radically smaller, highly adaptive and application-flexible underground coal mining machine, for performing non-production utility work and/or also undertake limited production mining for the recovery of reserves that would otherwise be lost. Whereas historically, mining philosophies have reflected a shift to increasing larger mechanized systems [such as the continuous miner (CM)], specific mining operations that do not benefit from the economy of the large mining equipment are often ignored or addressed with significant inefficiencies. Developing this prototype concept will create a new class of equipment that can provide opportunities to re-think the very structure of the mining system across a broad range of possibilities, not able to be met by existing machinery. The approach involved pooling the collective input from mining professionals, using a structured listing of desired inputs in the form of a questionnaire, which was used to define the range of desired design specifications. From these inputs, a conceptual specification was blended, by the author, to embody the general concurrence of mission concepts for this machine.

  4. Bulk micro-machined wide-band aero-acoustic microphone and its application to acoustic ranging

    NASA Astrophysics Data System (ADS)

    Zhou, Z. J.; Rufer, L.; Salze, E.; Yuldashev, P.; Ollivier, S.; Wong, M.

    2013-10-01

    A wide-band aero-acoustic microphone was realized using a bulk micro-machining process based on the deep reactive-ion etching of silicon. The sensing diaphragm is completely sealed, thus eliminating the loss of low-frequency response resulting from pressure equalization through the release etch-holes present on the diaphragm of a previously reported microphone implemented using a surface-micro-machining process. A dynamic sensitivity of ∼0.33 µV/V/Pa was estimated using an acoustic shockwave (‘N-wave’) generated using a custom-built high-voltage electrical spark-discharge system. This value is comparable to the effective static sensitivity of ∼0.28 µV/V/Pa measured using a commercial nano-indenter system. The response of the microphone is relatively flat from 6 to 500 kHz, with a resonance frequency of ∼715 kHz. An array of three microphones was also constructed and tested to demonstrate the application of these microphones to the localization of high frequency and short duration acoustic sources.

  5. Data Machine Independence

    1994-12-30

    Data-machine independence achieved by using four technologies (ASN.1, XDR, SDS, and ZEBRA) has been evaluated by encoding two different applications in each of the above; and their results compared against the standard programming method using C.

  6. Modeling workflow to design machine translation applications for public health practice

    PubMed Central

    Turner, Anne M.; Brownstein, Megumu K.; Cole, Kate; Karasz, Hilary; Kirchhoff, Katrin

    2014-01-01

    Objective Provide a detailed understanding of the information workflow processes related to translating health promotion materials for limited English proficiency individuals in order to inform the design of context-driven machine translation (MT) tools for public health (PH). Materials and Methods We applied a cognitive work analysis framework to investigate the translation information workflow processes of two large health departments in Washington State. Researchers conducted interviews, performed a task analysis, and validated results with PH professionals to model translation workflow and identify functional requirements for a translation system for PH. Results The study resulted in a detailed description of work related to translation of PH materials, an information workflow diagram, and a description of attitudes towards MT technology. We identified a number of themes that hold design implications for incorporating MT in PH translation practice. A PH translation tool prototype was designed based on these findings. Discussion This study underscores the importance of understanding the work context and information workflow for which systems will be designed. Based on themes and translation information workflow processes, we identified key design guidelines for incorporating MT into PH translation work. Primary amongst these is that MT should be followed by human review for translations to be of high quality and for the technology to be adopted into practice. Counclusion The time and costs of creating multilingual health promotion materials are barriers to translation. PH personnel were interested in MT's potential to improve access to low-cost translated PH materials, but expressed concerns about ensuring quality. We outline design considerations and a potential machine translation tool to best fit MT systems into PH practice. PMID:25445922

  7. Comparison of four machine learning algorithms for their applicability in satellite-based optical rainfall retrievals

    NASA Astrophysics Data System (ADS)

    Meyer, Hanna; Kühnlein, Meike; Appelhans, Tim; Nauss, Thomas

    2016-03-01

    Machine learning (ML) algorithms have successfully been demonstrated to be valuable tools in satellite-based rainfall retrievals which show the practicability of using ML algorithms when faced with high dimensional and complex data. Moreover, recent developments in parallel computing with ML present new possibilities for training and prediction speed and therefore make their usage in real-time systems feasible. This study compares four ML algorithms - random forests (RF), neural networks (NNET), averaged neural networks (AVNNET) and support vector machines (SVM) - for rainfall area detection and rainfall rate assignment using MSG SEVIRI data over Germany. Satellite-based proxies for cloud top height, cloud top temperature, cloud phase and cloud water path serve as predictor variables. The results indicate an overestimation of rainfall area delineation regardless of the ML algorithm (averaged bias = 1.8) but a high probability of detection ranging from 81% (SVM) to 85% (NNET). On a 24-hour basis, the performance of the rainfall rate assignment yielded R2 values between 0.39 (SVM) and 0.44 (AVNNET). Though the differences in the algorithms' performance were rather small, NNET and AVNNET were identified as the most suitable algorithms. On average, they demonstrated the best performance in rainfall area delineation as well as in rainfall rate assignment. NNET's computational speed is an additional advantage in work with large datasets such as in remote sensing based rainfall retrievals. However, since no single algorithm performed considerably better than the others we conclude that further research in providing suitable predictors for rainfall is of greater necessity than an optimization through the choice of the ML algorithm.

  8. Feature combination networks for the interpretation of statistical machine learning models: application to Ames mutagenicity

    PubMed Central

    2014-01-01

    Background A new algorithm has been developed to enable the interpretation of black box models. The developed algorithm is agnostic to learning algorithm and open to all structural based descriptors such as fragments, keys and hashed fingerprints. The algorithm has provided meaningful interpretation of Ames mutagenicity predictions from both random forest and support vector machine models built on a variety of structural fingerprints. A fragmentation algorithm is utilised to investigate the model’s behaviour on specific substructures present in the query. An output is formulated summarising causes of activation and deactivation. The algorithm is able to identify multiple causes of activation or deactivation in addition to identifying localised deactivations where the prediction for the query is active overall. No loss in performance is seen as there is no change in the prediction; the interpretation is produced directly on the model’s behaviour for the specific query. Results Models have been built using multiple learning algorithms including support vector machine and random forest. The models were built on public Ames mutagenicity data and a variety of fingerprint descriptors were used. These models produced a good performance in both internal and external validation with accuracies around 82%. The models were used to evaluate the interpretation algorithm. Interpretation was revealed that links closely with understood mechanisms for Ames mutagenicity. Conclusion This methodology allows for a greater utilisation of the predictions made by black box models and can expedite further study based on the output for a (quantitative) structure activity model. Additionally the algorithm could be utilised for chemical dataset investigation and knowledge extraction/human SAR development. PMID:24661325

  9. Holding Irregularly Shaped Parts For Machining

    NASA Technical Reports Server (NTRS)

    Hilton, Burt W.; Wilson, Rick R.

    1988-01-01

    Part with complicated, irregular outside contours clamped for precise machining of internal passages with aid of simple method. Exterior of part cast in Rigidex, or equivalent epoxy. Forms wall to be clamped. Interior of part machined to finish of 125 microinches or finer. When machining finished, epoxy melted away by heating part to 200 degree F.

  10. Precision Measurements at the ILC

    SciTech Connect

    Nelson, T.K.; /SLAC

    2006-12-06

    With relatively low backgrounds and a well-determined initial state, the proposed International Linear Collider (ILC) would provide a precision complement to the LHC experiments at the energy frontier. Completely and precisely exploring the discoveries of the LHC with such a machine will be critical in understanding the nature of those discoveries and what, if any, new physics they represent. The unique ability to form a complete picture of the Higgs sector is a prime example of the probative power of the ILC and represents a new era in precision physics.

  11. Laser machining - Theory and practice

    SciTech Connect

    Chryssolouris, G.

    1991-01-01

    Recent developments and the state of the art in the field of laser machining are reviewed with emphasis on practical applications. First, an overview of conventional material removing processes is presented. Laser machining systems are then described, and an overview is provided of the necessary knowledge from heat transfer and fluid mechanics required in order to understand the physical mechanisms and thermal processes associated with laser machining. The applications of laser machining discussed include drilling, cutting, marking, and three-dimensional machining of metals, ceramics, plastics, composites, and other materials, and micromachining. 209 refs.

  12. Application of Machine Learning tools to recognition of molecular patterns in STM images

    NASA Astrophysics Data System (ADS)

    Maksov, Artem; Ziatdinov, Maxim; Fujii, Shintaro; Kiguchi, Manabu; Higashibayashi, Shuhei; Sakurai, Hidehiro; Kalinin, Sergei; Sumpter, Bobby

    The ability to utilize individual molecules and molecular assemblies as data storage elements has motivated scientist for years, concurrent with the continuous effort to shrink a size of data storage devices in microelectronics industry. One of the critical issues in this effort lies in being able to identify individual molecular assembly units (patterns), on a large scale in an automated fashion of complete information extraction. Here we present a novel method of applying machine learning techniques for extraction of positional and rotational information from scanning tunneling microscopy (STM) images of π-bowl sumanene molecules on gold. We use Markov Random Field (MRF) model to decode the polar rotational states for each molecule in a large scale STM image of molecular film. We further develop an algorithm that uses a convolutional Neural Network combined with MRF and input from density functional theory to classify molecules into different azimuthal rotational classes. Our results demonstrate that a molecular film is partitioned into distinctive azimuthal rotational domains consisting typically of 20-30 molecules. In each domain, the ``bowl-down'' molecules are generally surrounded by six nearest neighbor molecules in ``bowl-up'' configuration, and the resultant overall structure form a periodic lattice of rotational and polar states within each domain. Research was supported by the US Department of Energy.

  13. Integrating Symbolic and Statistical Methods for Testing Intelligent Systems Applications to Machine Learning and Computer Vision

    SciTech Connect

    Jha, Sumit Kumar; Pullum, Laura L; Ramanathan, Arvind

    2016-01-01

    Embedded intelligent systems ranging from tiny im- plantable biomedical devices to large swarms of autonomous un- manned aerial systems are becoming pervasive in our daily lives. While we depend on the flawless functioning of such intelligent systems, and often take their behavioral correctness and safety for granted, it is notoriously difficult to generate test cases that expose subtle errors in the implementations of machine learning algorithms. Hence, the validation of intelligent systems is usually achieved by studying their behavior on representative data sets, using methods such as cross-validation and bootstrapping.In this paper, we present a new testing methodology for studying the correctness of intelligent systems. Our approach uses symbolic decision procedures coupled with statistical hypothesis testing to. We also use our algorithm to analyze the robustness of a human detection algorithm built using the OpenCV open-source computer vision library. We show that the human detection implementation can fail to detect humans in perturbed video frames even when the perturbations are so small that the corresponding frames look identical to the naked eye.

  14. A Machine Learning Approach to Automated Structural Network Analysis: Application to Neonatal Encephalopathy

    PubMed Central

    Ziv, Etay; Tymofiyeva, Olga; Ferriero, Donna M.; Barkovich, A. James; Hess, Chris P.; Xu, Duan

    2013-01-01

    Neonatal encephalopathy represents a heterogeneous group of conditions associated with life-long developmental disabilities and neurological deficits. Clinical measures and current anatomic brain imaging remain inadequate predictors of outcome in children with neonatal encephalopathy. Some studies have suggested that brain development and, therefore, brain connectivity may be altered in the subgroup of patients who subsequently go on to develop clinically significant neurological abnormalities. Large-scale structural brain connectivity networks constructed using diffusion tractography have been posited to reflect organizational differences in white matter architecture at the mesoscale, and thus offer a unique tool for characterizing brain development in patients with neonatal encephalopathy. In this manuscript we use diffusion tractography to construct structural networks for a cohort of patients with neonatal encephalopathy. We systematically map these networks to a high-dimensional space and then apply standard machine learning algorithms to predict neurological outcome in the cohort. Using nested cross-validation we demonstrate high prediction accuracy that is both statistically significant and robust over a broad range of thresholds. Our algorithm offers a novel tool to evaluate neonates at risk for developing neurological deficit. The described approach can be applied to any brain pathology that affects structural connectivity. PMID:24282501

  15. A Fully Implantable, Programmable and Multimodal Neuroprocessor for Wireless, Cortically Controlled Brain-Machine Interface Applications

    PubMed Central

    Zhang, Fei; Aghagolzadeh, Mehdi; Oweiss, Karim

    2012-01-01

    Reliability, scalability and clinical viability are of utmost importance in the design of wireless Brain Machine Interface systems (BMIs). This paper reports on the design and implementation of a neuroprocessor for conditioning raw extracellular neural signals recorded through microelectrode arrays chronically implanted in the brain of awake behaving rats. The neuroprocessor design exploits a sparse representation of the neural signals to combat the limited wireless telemetry bandwidth. We demonstrate a multimodal processing capability (monitoring, compression, and spike sorting) inherent in the neuroprocessor to support a wide range of scenarios in real experimental conditions. A wireless transmission link with rate-dependent compression strategy is shown to preserve information fidelity in the neural data. At 32 channels, the neuroprocessor has been fully implemented on a 5mm×5mm nano-FPGA, and the prototyping resulted in 5.19 mW power consumption, bringing its performance within the power-size constraints for clinical use. The optimal design for compression and sorting performance was evaluated for multiple sampling frequencies, wavelet basis choice and power consumption. PMID:23050029

  16. Application of symbolic representation method to the analysis of machine errors

    NASA Astrophysics Data System (ADS)

    Chen, Cha'o.-Kuang; Wu, Tzong-Mou

    1993-09-01

    jSYlIJIJOliC FepVCSCIltaLiOfl of rnachiiie errors for the opetied loop chain aJl(1 closed J():)fJ Cllaifl iii positioii and orientation is presented. i]iis representatioL1 (foes away with CtJJ11l)CrSOUC natrix rnuitiplicaiioiis and is able tO Ofilit 1ie zero value of multiplication of matrix. A program is also (leVeIolJC(I by I''iogran syrti holic rcj:ncseii lation method which is apjilicable to the analysis of nialiiiie Crrors. An example is given to illustrate the use of this prograiii for the analysis of machue errors. it is hoped that the itietliod presented if! this study will provide an easy and powerful tool for the analysis of machine errors. In iroduc Lion lfoclianism are commonly used in . i specified pOSitiOfl and orienLation in two or Ldimensional space. In accuracies introduced by clearances in the mechanism connections and errors j manufacturing are one of the prin SP1E Vol. 2101 Measurement Technology and Intelligent Instruments (1993)! 155

  17. Shear melting and high temperature embrittlement: theory and application to machining titanium.

    PubMed

    Healy, Con; Koch, Sascha; Siemers, Carsten; Mukherji, Debashis; Ackland, Graeme J

    2015-04-24

    We describe a dynamical phase transition occurring within a shear band at high temperature and under extremely high shear rates. With increasing temperature, dislocation deformation and grain boundary sliding are supplanted by amorphization in a highly localized nanoscale band, which allows for massive strain and fracture. The mechanism is similar to shear melting and leads to liquid metal embrittlement at high temperature. From simulation, we find that the necessary conditions are lack of dislocation slip systems, low thermal conduction, and temperature near the melting point. The first two are exhibited by bcc titanium alloys, and we show that the final one can be achieved experimentally by adding low-melting-point elements: specifically, we use insoluble rare earth metals (REMs). Under high shear, the REM becomes mixed with the titanium, lowering the melting point within the shear band and triggering the shear-melting transition. This in turn generates heat which remains localized in the shear band due to poor heat conduction. The material fractures along the shear band. We show how to utilize this transition in the creation of new titanium-based alloys with improved machinability.

  18. Shear Melting and High Temperature Embrittlement: Theory and Application to Machining Titanium

    NASA Astrophysics Data System (ADS)

    Healy, Con; Koch, Sascha; Siemers, Carsten; Mukherji, Debashis; Ackland, Graeme J.

    2015-04-01

    We describe a dynamical phase transition occurring within a shear band at high temperature and under extremely high shear rates. With increasing temperature, dislocation deformation and grain boundary sliding are supplanted by amorphization in a highly localized nanoscale band, which allows for massive strain and fracture. The mechanism is similar to shear melting and leads to liquid metal embrittlement at high temperature. From simulation, we find that the necessary conditions are lack of dislocation slip systems, low thermal conduction, and temperature near the melting point. The first two are exhibited by bcc titanium alloys, and we show that the final one can be achieved experimentally by adding low-melting-point elements: specifically, we use insoluble rare earth metals (REMs). Under high shear, the REM becomes mixed with the titanium, lowering the melting point within the shear band and triggering the shear-melting transition. This in turn generates heat which remains localized in the shear band due to poor heat conduction. The material fractures along the shear band. We show how to utilize this transition in the creation of new titanium-based alloys with improved machinability.

  19. Shear melting and high temperature embrittlement: theory and application to machining titanium.

    PubMed

    Healy, Con; Koch, Sascha; Siemers, Carsten; Mukherji, Debashis; Ackland, Graeme J

    2015-04-24

    We describe a dynamical phase transition occurring within a shear band at high temperature and under extremely high shear rates. With increasing temperature, dislocation deformation and grain boundary sliding are supplanted by amorphization in a highly localized nanoscale band, which allows for massive strain and fracture. The mechanism is similar to shear melting and leads to liquid metal embrittlement at high temperature. From simulation, we find that the necessary conditions are lack of dislocation slip systems, low thermal conduction, and temperature near the melting point. The first two are exhibited by bcc titanium alloys, and we show that the final one can be achieved experimentally by adding low-melting-point elements: specifically, we use insoluble rare earth metals (REMs). Under high shear, the REM becomes mixed with the titanium, lowering the melting point within the shear band and triggering the shear-melting transition. This in turn generates heat which remains localized in the shear band due to poor heat conduction. The material fractures along the shear band. We show how to utilize this transition in the creation of new titanium-based alloys with improved machinability. PMID:25955055

  20. Single-trial dynamics of motor cortex and their applications to brain-machine interfaces

    PubMed Central

    Kao, Jonathan C.; Nuyujukian, Paul; Ryu, Stephen I.; Churchland, Mark M.; Cunningham, John P.; Shenoy, Krishna V.

    2015-01-01

    Increasing evidence suggests that neural population responses have their own internal drive, or dynamics, that describe how the neural population evolves through time. An important prediction of neural dynamical models is that previously observed neural activity is informative of noisy yet-to-be-observed activity on single-trials, and may thus have a denoising effect. To investigate this prediction, we built and characterized dynamical models of single-trial motor cortical activity. We find these models capture salient dynamical features of the neural population and are informative of future neural activity on single trials. To assess how neural dynamics may beneficially denoise single-trial neural activity, we incorporate neural dynamics into a brain–machine interface (BMI). In online experiments, we find that a neural dynamical BMI achieves substantially higher performance than its non-dynamical counterpart. These results provide evidence that neural dynamics beneficially inform the temporal evolution of neural activity on single trials and may directly impact the performance of BMIs. PMID:26220660

  1. Application of biomonitoring and support vector machine in water quality assessment*

    PubMed Central

    Liao, Yue; Xu, Jian-yu; Wang, Zhu-wei

    2012-01-01

    The behavior of schools of zebrafish (Danio rerio) was studied in acute toxicity environments. Behavioral features were extracted and a method for water quality assessment using support vector machine (SVM) was developed. The behavioral parameters of fish were recorded and analyzed during one hour in an environment of a 24-h half-lethal concentration (LC50) of a pollutant. The data were used to develop a method to evaluate water quality, so as to give an early indication of toxicity. Four kinds of metal ions (Cu2+, Hg2+, Cr6+, and Cd2+) were used for toxicity testing. To enhance the efficiency and accuracy of assessment, a method combining SVM and a genetic algorithm (GA) was used. The results showed that the average prediction accuracy of the method was over 80% and the time cost was acceptable. The method gave satisfactory results for a variety of metal pollutants, demonstrating that this is an effective approach to the classification of water quality. PMID:22467374

  2. Assessment of machine learning reliability methods for quantifying the applicability domain of QSAR regression models.

    PubMed

    Toplak, Marko; Močnik, Rok; Polajnar, Matija; Bosnić, Zoran; Carlsson, Lars; Hasselgren, Catrin; Demšar, Janez; Boyer, Scott; Zupan, Blaž; Stålring, Jonna

    2014-02-24

    The vastness of chemical space and the relatively small coverage by experimental data recording molecular properties require us to identify subspaces, or domains, for which we can confidently apply QSAR models. The prediction of QSAR models in these domains is reliable, and potential subsequent investigations of such compounds would find that the predictions closely match the experimental values. Standard approaches in QSAR assume that predictions are more reliable for compounds that are "similar" to those in subspaces with denser experimental data. Here, we report on a study of an alternative set of techniques recently proposed in the machine learning community. These methods quantify prediction confidence through estimation of the prediction error at the point of interest. Our study includes 20 public QSAR data sets with continuous response and assesses the quality of 10 reliability scoring methods by observing their correlation with prediction error. We show that these new alternative approaches can outperform standard reliability scores that rely only on similarity to compounds in the training set. The results also indicate that the quality of reliability scoring methods is sensitive to data set characteristics and to the regression method used in QSAR. We demonstrate that at the cost of increased computational complexity these dependencies can be leveraged by integration of scores from various reliability estimation approaches. The reliability estimation techniques described in this paper have been implemented in an open source add-on package ( https://bitbucket.org/biolab/orange-reliability ) to the Orange data mining suite. PMID:24490838

  3. Automatic QSO Selection Using Machine Learning: Application on Massive Astronomical Database

    NASA Astrophysics Data System (ADS)

    Kim, D.-W.; Protopapas, P.; Alcock, C.; Byun, Y.-I.; Khardon, R.

    2011-07-01

    We present a new QSO (Quasi-Stellar Object) selection algorithm using Support Vector Machine (SVM), a supervised classification method, on a set of multiple extracted times series features such as period, amplitude, color, and autocorrelation value. We train a model that separates QSOs from variable stars, non-variable stars and microlensing events using the richest possible training set consisting of all known types of variables including QSOs from the MAssive Compact Halo Object (MACHO) database. We applied the trained model on the MACHO Large Magellanic Cloud (LMC) dataset, which consists of 40 million lightcurves, and found 1,620 QSO candidates. During the selection none of the 33,242 known MACHO variables were misclassified as QSO candidates. In order to estimate the true false positive rate, we crossmatched the candidates with astronomical catalogs including the Spitzer Surveying the Agents of a Galaxy's Evolution (SAGE) LMC catalog. The results further suggest that the majority of the candidates, more than 70%, are QSOs.

  4. Application of Phase Smoothing Pseudo Range PPP/INS Tightly Coupled Technique in Improving the Results of Low Precision MEMS

    NASA Astrophysics Data System (ADS)

    Luo, X.

    2015-12-01

    In land surveying and engineering surveying, we need to obtain high precision navigation results. However, due to the inertial device costs less than a introduction, commonly used low precision inertial navigation equipment with tightly coupled GPS / INS integrated to get high precision navigation results. Many studies have improved the accuracy of error by using the UKF and CKF filtering algorithm, but it is still using the traditional pseudo code directly, the improvement effect is not obvious, and the disturbance is large. In this study, the PPP /INSmodel is improved by using the carrier phase smoothing pseudo range algorithm. Experimental results show that based on phase smoothing pseudo range PPP/INS tight coupled method, the position precision and the velocity precision for of the measured data of higher accuracy of MEMS and GPS receiver can get to a decimeter level and centimeter level. This coupling method has higher accuracy, stronger anti disturbance and Have a better convergence than the traditional C/A code. Based on different phase smoothing epoch number combination the accuracy and smoothing effect is also different, the larger smooth epoch number is, the better treatment effect it has and The higher precision it has. For high precision measurement, the equipment cost is saved. It has a practical significance meaning in the measurement of outdoor ground.

  5. Multilabel immunofluorescence and antigen reprobing on formalin-fixed paraffin-embedded sections: novel applications for precision pathology diagnosis.

    PubMed

    Pan, Jie; Thoeni, Cornelia; Muise, Aleixo; Yeger, Herman; Cutz, Ernest

    2016-06-01

    We report new methods for multilabel immunofluorescence (MIF) and reprobing of antigen epitopes on the same formalin-fixed paraffin-embedded (FFPE) sections. The MIF method includes an antigen-retrieval step followed by multilabel immunostaining and examination by confocal microscopy. As examples, we illustrate epitopes localized to the apical and basolateral membranes, and the cytoplasm of enterocytes of normal small intestine and in cases of congenital enteropathies (microvillous inclusion disease and congenital tufting enteropathy). We also demonstrate localization of the bile salt excretion pump protein (BSEP) in bile canalicular membrane of normal hepatocytes and in cases of primary sclerosing cholangitis. To demonstrate colocalization of cytoplasmic and nuclear epitopes we analyzed normal control and hyperplastic pulmonary neuroendocrine cells (PNEC) and neuroepithelial bodies (NEBs), presumed airway sensors in the lungs of infants with bronchopulmonary dysplasia (BPD). As cytoplasmic markers we used anti-bombesin or anti-synaptic vesicle protein 2 (SV2) antibody, respectively, and for nuclear localization, antibodies against neurogenic genes mammalian achaete-scute homolog (Mash1) and prospero homeobox 1 (Prox1), essential for NEB cells differentiation and maturation, hypoxia-inducible factor 1α (HIF1α) a downstream modulator of hypoxia response and a proliferation marker Ki67. The reprobing method consisted of removal of the previously immunolabeled target and immunostaining with different antibodies, facilitating colocalization of enterocyte brush border epitopes as well as HIF1α, Mash1 and Prox1 in PNEC/NEB PNEC and NEBs. As these methods are suitable for routine FFPE pathology samples from various tissues, allowing visualization of multiple epitopes in the same cells/sections with superior contrast and resolution, they are suitable for a wide range of applications in diagnostic pathology and may be particularly well suited for precision medicine

  6. DNA-based machines.

    PubMed

    Wang, Fuan; Willner, Bilha; Willner, Itamar

    2014-01-01

    The base sequence in nucleic acids encodes substantial structural and functional information into the biopolymer. This encoded information provides the basis for the tailoring and assembly of DNA machines. A DNA machine is defined as a molecular device that exhibits the following fundamental features. (1) It performs a fuel-driven mechanical process that mimics macroscopic machines. (2) The mechanical process requires an energy input, "fuel." (3) The mechanical operation is accompanied by an energy consumption process that leads to "waste products." (4) The cyclic operation of the DNA devices, involves the use of "fuel" and "anti-fuel" ingredients. A variety of DNA-based machines are described, including the construction of "tweezers," "walkers," "robots," "cranes," "transporters," "springs," "gears," and interlocked cyclic DNA structures acting as reconfigurable catenanes, rotaxanes, and rotors. Different "fuels", such as nucleic acid strands, pH (H⁺/OH⁻), metal ions, and light, are used to trigger the mechanical functions of the DNA devices. The operation of the devices in solution and on surfaces is described, and a variety of optical, electrical, and photoelectrochemical methods to follow the operations of the DNA machines are presented. We further address the possible applications of DNA machines and the future perspectives of molecular DNA devices. These include the application of DNA machines as functional structures for the construction of logic gates and computing, for the programmed organization of metallic nanoparticle structures and the control of plasmonic properties, and for controlling chemical transformations by DNA machines. We further discuss the future applications of DNA machines for intracellular sensing, controlling intracellular metabolic pathways, and the use of the functional nanostructures for drug delivery and medical applications.

  7. DNA-based machines.

    PubMed

    Wang, Fuan; Willner, Bilha; Willner, Itamar

    2014-01-01

    The base sequence in nucleic acids encodes substantial structural and functional information into the biopolymer. This encoded information provides the basis for the tailoring and assembly of DNA machines. A DNA machine is defined as a molecular device that exhibits the following fundamental features. (1) It performs a fuel-driven mechanical process that mimics macroscopic machines. (2) The mechanical process requires an energy input, "fuel." (3) The mechanical operation is accompanied by an energy consumption process that leads to "waste products." (4) The cyclic operation of the DNA devices, involves the use of "fuel" and "anti-fuel" ingredients. A variety of DNA-based machines are described, including the construction of "tweezers," "walkers," "robots," "cranes," "transporters," "springs," "gears," and interlocked cyclic DNA structures acting as reconfigurable catenanes, rotaxanes, and rotors. Different "fuels", such as nucleic acid strands, pH (H⁺/OH⁻), metal ions, and light, are used to trigger the mechanical functions of the DNA devices. The operation of the devices in solution and on surfaces is described, and a variety of optical, electrical, and photoelectrochemical methods to follow the operations of the DNA machines are presented. We further address the possible applications of DNA machines and the future perspectives of molecular DNA devices. These include the application of DNA machines as functional structures for the construction of logic gates and computing, for the programmed organization of metallic nanoparticle structures and the control of plasmonic properties, and for controlling chemical transformations by DNA machines. We further discuss the future applications of DNA machines for intracellular sensing, controlling intracellular metabolic pathways, and the use of the functional nanostructures for drug delivery and medical applications. PMID:24647836

  8. Characteristics for electrochemical machining with nanoscale voltage pulses.

    PubMed

    Lee, E S; Back, S Y; Lee, J T

    2009-06-01

    Electrochemical machining has traditionally been used in highly specialized fields, such as those of the aerospace and defense industries. It is now increasingly being applied in other industries, where parts with difficult-to-cut material, complex geometry and tribology, and devices of nanoscale and microscale are required. Electric characteristic plays a principal function role in and chemical characteristic plays an assistant function role in electrochemical machining. Therefore, essential parameters in electrochemical machining can be described current density, machining time, inter-electrode gap size, electrolyte, electrode shape etc. Electrochemical machining provides an economical and effective method for machining high strength, high tension and heat-resistant materials into complex shapes such as turbine blades of titanium and aluminum alloys. The application of nanoscale voltage pulses between a tool electrode and a workpiece in an electrochemical environment allows the three-dimensional machining of conducting materials with sub-micrometer precision. In this study, micro probe are developed by electrochemical etching and micro holes are manufactured using these micro probe as tool electrodes. Micro holes and microgroove can be accurately achieved by using nanoscale voltages pulses. PMID:19504864

  9. Introduction to machine learning.

    PubMed

    Baştanlar, Yalin; Ozuysal, Mustafa

    2014-01-01

    The machine learning field, which can be briefly defined as enabling computers make successful predictions using past experiences, has exhibited an impressive development recently with the help of the rapid increase in the storage capacity and processing power of computers. Together with many other disciplines, machine learning methods have been widely employed in bioinformatics. The difficulties and cost of biological analyses have led to the development of sophisticated machine learning approaches for this application area. In this chapter, we first review the fundamental concepts of machine learning such as feature assessment, unsupervised versus supervised learning and types of classification. Then, we point out the main issues of designing machine learning experiments and their performance evaluation. Finally, we introduce some supervised learning methods. PMID:24272434

  10. Introduction to machine learning.

    PubMed

    Baştanlar, Yalin; Ozuysal, Mustafa

    2014-01-01

    The machine learning field, which can be briefly defined as enabling computers make successful predictions using past experiences, has exhibited an impressive development recently with the help of the rapid increase in the storage capacity and processing power of computers. Together with many other disciplines, machine learning methods have been widely employed in bioinformatics. The difficulties and cost of biological analyses have led to the development of sophisticated machine learning approaches for this application area. In this chapter, we first review the fundamental concepts of machine learning such as feature assessment, unsupervised versus supervised learning and types of classification. Then, we point out the main issues of designing machine learning experiments and their performance evaluation. Finally, we introduce some supervised learning methods.

  11. An Improved Method for TIMS High Precision Nd Isotopic Analysis of Very Small Aliquots (1- 10ng) With Example Application in Garnet Sm/Nd Geochronology

    NASA Astrophysics Data System (ADS)

    Baxter, E. F.; Harvey, J.; Mehl, L. Y.; Peterman, E. M.

    2007-12-01

    Technological and scientific developments have demonstrated both the attainability and the utility of very high precision (i.e. 5-20ppm 2 σ) Nd isotopic measurements with TIMS. However such high precision has been limited to relatively large aliquots of Nd, on the order of several hundred nanograms. Several potential applications of precise Nd isotopic measurements, including garnet Sm/Nd geochronology, do not always permit such large samples, instead yielding only a few nanograms of Nd. We have explored and tested an improved method for Nd isotopic analysis of such small (1-10ng) aliquots of Nd using the NdO+ method with a Triton TIMS at Boston University. Analyzing Nd isotopes as the oxide is a well known technique, frequently involving an oxygen bleed valve. Instead, we forego the bleed valve and load samples with a TaO slurry which provides the oxygen source. Using an in-house Nd isotopic standard solution, 4ng loads easily yield stable 2.0-2.5 volt beams resulting in internal precisions of 10ppm 2 σ RSE. Within barrel external precision of 4ng loads of the Nd standard is 13ppm 2 σ RSD (n=20). Long term (6 months, six analysts) external precision of 4ng loads of the standard is currently 23ppm 2 σ RSD (n=55) suggesting that further improvements are possible. As a further test of this method, we dissolved a natural rock sample (a metapelite), separated the Nd using TRU- spec and MLA column chemistry, and loaded nineteen 4ng loads in one barrel. Within barrel external precision was 21ppm 2 σ RSD (n=18). This precision represents a significant advance over previous NdO+ analyses of small samples using an oxygen bleed valve. The TaO loading method for small Nd aliquots is useful in Sm/Nd garnet geochronology as exemplified by two case studies. Garnets from eclogite facies gneisses from Norway ran very well with 2.4-18ng loads and yielded age precision as good as 0.8 million years 2 σ. Conversely, garnets from blueschist facies rocks from Sifnos, Greece, ran

  12. A machine learning based method to improve docking scoring functions and its application to drug repurposing

    PubMed Central

    Kinnings, Sarah L.; Liu, Nina; Tonge, Peter J.; Jackson, Richard M.; Xie, Lei; Bourne, Philip E.

    2011-01-01

    Docking scoring functions are notoriously weak predictors of binding affinity. They typically assign a common set of weights to the individual energy terms that contribute to the overall energy score, however, these weights should be gene family-dependent. In addition, they incorrectly assume that individual interactions contribute towards the total binding affinity in an additive manner. In reality, noncovalent interactions often depend on one another in a nonlinear manner. In this paper we show how the use of support vector machines (SVMs), trained by associating sets of individual energy terms retrieved from molecular docking with the known binding affinity of each compound from high-throughput screening experiments, can be used to improve the correlation between known binding affinities and those predicted by the docking program eHiTS. We construct two prediction models; a regression model trained using IC50 values from BindingDB, and a classification model trained using active and decoy compounds from the Directory of Useful Decoys (DUD). Moreover, to address the issue of overrepresentation of negative data in high-throughput screening data sets, we have designed a multiple-planar SVM training procedure for the classification model. The increased performance that both SVMs give when compared with the original eHiTS scoring function highlights the potential for using nonlinear methods when deriving overall energy scores from their individual components. We apply the above methodology to train a new scoring function for direct inhibitors of M.tuberculosis (M.tb) InhA. By combining ligand binding site comparison with the new scoring function, we propose that phosphodiesterase inhibitors can potentially be repurposed to target M.tb InhA. Our methodology may be applied to other gene families for which target structures and activity data are available, as demonstrated in the work presented here. PMID:21291174

  13. General Methodologies for Improving Motor Drive Precision in Order to Utilize It as an Embedded Application Sensor

    NASA Astrophysics Data System (ADS)

    Secrest, Caleb W.

    The objectives of this research are to reliably, and non-invasively, extract high quality spatial information from a limited-stroke multi-stage gear train driven by an AC machine using only the sensors necessary for normal AC machine control. In this work, the spatial information will be used to estimate the state of wear of each axis in the gear train. To extract this information, cascaded observer structures are utilized to estimate the load disturbances acting on the AC machine, and then to estimate the spatial errors which produce those disturbances. Further signal processing techniques are then utilized to observe the spatial error information in the spatial domain where the information is most relevant and to extract the systematic spatial errors that reoccur over many operating cycles. In prior art, the intrinsic spatial properties of the AC machine and position sensor feedback limited the quality of the spatial error information that could be extracted using motor drive-based estimation. Furthermore, the limited-stroke of the multi-stage gear train limits the separation of spatial content between the axes of the gear train and limits the extraction of the systematic spatial errors that reoccur over many operating cycles. In this work, methods are developed to reduce and separate machine and sensor contributions to the spatial error information being extracted, and general system design methodologies are investigated to improve the quality of spatial error information that can be extracted within the limited-stroke motion constraints of the multi-stage gear train.

  14. Precision translator

    DOEpatents

    Reedy, R.P.; Crawford, D.W.

    1982-03-09

    A precision translator for focusing a beam of light on the end of a glass fiber which includes two turning fork-like members rigidly connected to each other. These members have two prongs each with its separation adjusted by a screw, thereby adjusting the orthogonal positioning of a glass fiber attached to one of the members. This translator is made of simple parts with capability to keep adjustment even in condition of rough handling.

  15. Precision translator

    DOEpatents

    Reedy, Robert P.; Crawford, Daniel W.

    1984-01-01

    A precision translator for focusing a beam of light on the end of a glass fiber which includes two turning fork-like members rigidly connected to each other. These members have two prongs each with its separation adjusted by a screw, thereby adjusting the orthogonal positioning of a glass fiber attached to one of the members. This translator is made of simple parts with capability to keep adjustment even in condition of rough handling.

  16. Multipolar electrostatics based on the Kriging machine learning method: an application to serine.

    PubMed

    Yuan, Yongna; Mills, Matthew J L; Popelier, Paul L A

    2014-04-01

    A multipolar, polarizable electrostatic method for future use in a novel force field is described. Quantum Chemical Topology (QCT) is used to partition the electron density of a chemical system into atoms, then the machine learning method Kriging is used to build models that relate the multipole moments of the atoms to the positions of their surrounding nuclei. The pilot system serine is used to study both the influence of the level of theory and the set of data generator methods used. The latter consists of: (i) sampling of protein structures deposited in the Protein Data Bank (PDB), or (ii) normal mode distortion along either (a) Cartesian coordinates, or (b) redundant internal coordinates. Wavefunctions for the sampled geometries were obtained at the HF/6-31G(d,p), B3LYP/apc-1, and MP2/cc-pVDZ levels of theory, prior to calculation of the atomic multipole moments by volume integration. The average absolute error (over an independent test set of conformations) in the total atom-atom electrostatic interaction energy of serine, using Kriging models built with the three data generator methods is 11.3 kJ mol⁻¹ (PDB), 8.2 kJ mol⁻¹ (Cartesian distortion), and 10.1 kJ mol⁻¹ (redundant internal distortion) at the HF/6-31G(d,p) level. At the B3LYP/apc-1 level, the respective errors are 7.7 kJ mol⁻¹, 6.7 kJ mol⁻¹, and 4.9 kJ mol⁻¹, while at the MP2/cc-pVDZ level they are 6.5 kJ mol⁻¹, 5.3 kJ mol⁻¹, and 4.0 kJ mol⁻¹. The ranges of geometries generated by the redundant internal coordinate distortion and by extraction from the PDB are much wider than the range generated by Cartesian distortion. The atomic multipole moment and electrostatic interaction energy predictions for the B3LYP/apc-1 and MP2/cc-pVDZ levels are similar, and both are better than the corresponding predictions at the HF/6-31G(d,p) level.

  17. Applications of artificial intelligence X: Machine vision and robotics; Proceedings of the Meeting, Orlando, FL, Apr. 22-24, 1992

    SciTech Connect

    Bowyer, K.W.

    1992-01-01

    Various papers on artificial intelligence in machine vision and robotics are presented. The general topics addressed include: design of a robot head, machine vision inspection techniques, segmentation of fused range and intensity imagery, parallel and VLSI architectures for machine vision, comparison of range image segmentation algorithms, state of the art in postcanny edge detection, simulation and visualization environments for autonomous robots, exploration of recognition by components representation and matching, reactive robotic control strategies, image processing techniques.

  18. Wind motor machine

    SciTech Connect

    Goedecke, A.

    1984-12-25

    An improved wind motor machine having a wind rotor rotatable about a vertical axis. The rotor core body of the machine is provided with convexly curved wind application surfaces and coacting outer wing bodies having load supporting airplane wing-shaped cross-sections. The efficiency of the machine is improved by means of stream guiding bodies disposed in the intermediate space between the rotor core body and the wing bodies. These stream guiding bodies extend in a desired streaming direction, that is normal to the rotational axis of the wind body, which insures substantially laminar air streaming within the intermediate space.

  19. Memristor models for machine learning.

    PubMed

    Carbajal, Juan Pablo; Dambre, Joni; Hermans, Michiel; Schrauwen, Benjamin

    2015-03-01

    In the quest for alternatives to traditional complementary metal-oxide-semiconductor, it is being suggested that digital computing efficiency and power can be improved by matching the precision to the application. Many applications do not need the high precision that is being used today. In particular, large gains in area and power efficiency could be achieved by dedicated analog realizations of approximate computing engines. In this work we explore the use of memristor networks for analog approximate computation, based on a machine learning framework called reservoir computing. Most experimental investigations on the dynamics of memristors focus on their nonvolatile behavior. Hence, the volatility that is present in the developed technologies is usually unwanted and is not included in simulation models. In contrast, in reservoir computing, volatility is not only desirable but necessary. Therefore, in this work, we propose two different ways to incorporate it into memristor simulation models. The first is an extension of Strukov's model, and the second is an equivalent Wiener model approximation. We analyze and compare the dynamical properties of these models and discuss their implications for the memory and the nonlinear processing capacity of memristor networks. Our results indicate that device variability, increasingly causing problems in traditional computer design, is an asset in the context of reservoir computing. We conclude that although both models could lead to useful memristor-based reservoir computing systems, their computational performance will differ. Therefore, experimental modeling research is required for the development of accurate volatile memristor models.

  20. BeiDou phase bias estimation and its application in precise point positioning with triple-frequency observable

    NASA Astrophysics Data System (ADS)

    Gu, Shengfeng; Lou, Yidong; Shi, Chuang; Liu, Jingnan

    2015-10-01

    At present, the BeiDou system (BDS) enables the practical application of triple-frequency observable in the Asia-Pacific region, of many possible benefits from the additional signal; this study focuses on exploiting the contribution of zero difference (ZD) ambiguity resolution (AR) to the precise point positioning (PPP). A general modeling strategy for multi-frequency PPP AR is presented, in which, the least squares ambiguity decorrelation adjustment (LAMBDA) method is employed in ambiguity fixing based on the full variance-covariance ambiguity matrix generated from the raw data processing model. Because of the reliable fixing of BDS L1 ambiguity faces more difficulty, the LAMBDA method with partial ambiguity fixing is proposed to enable the independent and instantaneous resolution of extra wide-lane (EWL) and wide-lane (WL). This mechanism of sequential ambiguity fixing is demonstrated for resolving ZD satellite phase bias and performing triple-frequency PPP AR with two reference station networks with a typical baseline of up to 400 and 800 km, respectively. Tests show that about of the EWL and WL phase bias of BDS has a consistency of better than 0.1 cycle, and this value decreases to 80 % for L1 phase bias for Experiment I, while all the solutions of Experiment II have a similar RMS of about 0.12 cycles. In addition, the repeatability of the daily mean phase bias agree to 0.093 cycles and 0.095 cycles for EWL and WL on average, which is much smaller than 0.20 cycles of L1. To assess the improvement of fixed PPP brought by applying the third frequency signal as well as the above phase bias, various ambiguity fixing strategy are considered in the numerical demonstration. It is shown that the impact of the additional signal is almost negligible when only float solution involved. It is also shown that by fixing EWL and WL together, as opposed to the single ambiguity fixing, will leads to an improvement in PPP accuracy by about on average. Attributed to the efficient